"Australia - the Island Continent",1,14050048.jpg,c,0
Australia is the smallest of the worldÆs seven continents, but the sixth largest country and the only country to occupy an entire continent. It is the only permanently inhabited continent that lies wholly in the southern hemisphere.
The southern hemisphere is mainly water, and is markedly less affected by human activities than the northern. Australia lies in relatively unpolluted air and sea. Its comparative isolation means that transboundary pollution is not as significant an issue as it is for many northern hemisphere countries.
\BContinental Australia\b
Many of AustraliaÆs unusual features are important in assessing the state of its environment.
\IIt is the worldÆs lowest continent.\i Australia has the lowest average elevation and the lowest absolute relief (the difference between highest and lowest points). This is partly a result of its geological stability. Its few mountain ranges are very low by world standards, and most of the country is a broad flat platform.
\IIt is geologically stable.\i Australia has some of the oldest land surface on Earth. Much of this surface has been weathering and eroding for long periods of geological time. It is the only continent that has no tectonic mountain building or active volcanoes.
\IIt is the driest inhabited continent.\i Australia receives the lowest annual average rainfall, apart from Antarctica. Its latitude puts it in a low rainfall zone. The lack of mountains, which tend to increase rainfall, is also a factor. More than one-third of Australia is classified as arid (receiving an average of less than 250 mm of rain a year), and another third is semi-arid (receiving 250û500 mm).
\IIts climate, especially the rainfall, is highly variable.\i Averages can be very misleading: in some places much of the annual rainfall can fall in a week or so; in others, the annual rainfall can vary from a fraction of the annual average to several times its size. Changes in sea temperature and atmospheric pressure associated with a suite of events known as the El Ni±oûSouthern Oscillation, or ENSO, are a major cause of this variability.
\IIt has fewer sizeable rivers and less run-off than any other continent, except Antarctica.\i The low rainfall means that, for its size, Australia has few sizeable rivers, and accumulates little fresh water on its surface.
\IIt has large, but diminishing, groundwater resources.\i Australia is well provided with (under)groundwater that can be tapped with bores and wells. The largest source, the Great Artesian Basin, is huge, underlying about 22 per cent of the continent. Groundwater is being used much faster than it is replenished.
\IIts soils are generally poor.\i Australian soils are among the most nutrient-poor and unproductive in the world. This is mainly because of the countryÆs geological stability, with many soil components having been leached out during the landÆs long exposure to weathering. The dryness also mitigates against the formation of rich, deep soils. Less than 10 per cent of the country has reasonably productive soils that can sustain intensive agriculture or dense vegetation.
\IIt is a land of natural hazards.\i These are part of AustraliaÆs natural environmental variability. Drought, flood, fire, earthquake, storm and tropical cyclone are normal features of the land. Large fires occur somewhere in Australia every month of the year. Much of the native vegetation is adapted to fire, and many species need it to reproduce. The frequency of fires is not just a result of the hot and dry climate, but also its variability. Wet periods allow vegetation to build up as fuel for fires in dry times. The flammability of eucalyptus oil and the dry leaves of many plants also contribute.
\IIt is rich in minerals.\i Australia has more than 20 per cent of the worldÆs stock of recoverable bauxite, iron ore, uranium, mineral sands and diamonds. Coal is another important mineral resource.
\BAustraliaÆs seas\b
AustraliaÆs seas are an important part of its environment, both in their own right and because of the influence they have on the terrestrial environment, especially its climate.
Australia sits between three ocean basins ù the Pacific, Indian and Southern. Its ocean territory, as defined by the 200-nautical-mile Exclusive Economic Zone (EEZ), covers about 12 million square kilometres, about one and half times its land area (7.6 million square kilometres). It is the third largest EEZ in the world.
The adoption of the EEZ in 1994 gives Australia rights to explore, exploit and manage the zoneÆs natural resources. It also imposes responsibilities to conserve the zoneÆs rich diversity of living organisms.
Australia has several important marine features.
\IIt has warm ocean currents.\i Australia has a major ocean current passing down each side of the continent, bringing warm water from the tropics to both east and west coasts. This feature is unusual, as most other continents have a æcoldÆ current, from the polar regions, running along one side, and a æwarmÆ current, from the tropics, along the other.
\IIts seas are not highly productive by world standards.\i The lack of an upwelling of cold waters, rich in nutrients and oxygen, is one reason. Another is lack of run-off from the land and the low level of nutrients in the run-off. Despite the large size of our fishing zone, the total fish catch is low by world standards, ranking about 50th by production (although most of the catch has a high unit value).
\IIt has the worldÆs largest coral reef.\i The most famous feature of AustraliaÆs seas is the worldÆs largest continuous coral reef complex, the Great Barrier Reef. The reef extends about 2500 kilometres along the north-east coast. Near its southern end lies the worldÆs largest sand island, Fraser Island. Both the reef and the island are World Heritage Areas.
\BAustraliaÆs biology\b
AustraliaÆs unique physical characteristics have made its biology distinctive.
\IIt has a rich biodiversity.\i Australia is one of the twelve most biologically diverse countries in the world, a status owed to its size, long isolation and many climatic zones.
\IMany of its plants and animals are unique.\i Australia has a very high degree of endemism ù that is, many of its plants, animals and micro-organisms are not found elsewhere in the world. This is because they have evolved in isolation.
\IIts vegetation is dominated by two genera of trees ù Eucalyptus and Acacia.\i Acacias are widespread in southern continents, although Australian species are endemic. Eucalypts are mostly confined to Australia and New Guinea, with a few species occurring in other islands to our north.
\IMost plants are sclerophylls.\i A particular quality of much of the Australian flora is the hard, dryish, leathery, spiny or small leaves. These plants are called sclerophylls. They are well adapted to dry conditions and low-nutrient soils. Their leaves lose less moisture and are tougher, so lasting longer and needing replacement less often.
\IAustralia is the undisputed world centre for marsupials.\i Several families of marsupials (mammals whose young develop in a pouch) occur in South America and one species in North America; Australia has about 144 marsupial species.
Monotremes (mammals that lay eggs) are even more special. Only three species exist ù the platypus and two echidnas (one is in New Guinea). There is also a large number of native placental mammals (in which the young develop in the womb), mainly bats, rodents and marine mammals.
\IIts tropical rainforests are small but rich.\i AustraliaÆs tropical rainforests are distinctive ù again a consequence of the continentÆs long isolation. While covering only 0.1 per cent of the land area, they contain a large proportion of AustraliaÆs known plant and animal species. Many rainforest species have not been scientifically described, and there are probably many more, especially invertebrates, that remain undiscovered.
\IIntroduced species have ærun wildÆ.\i In the past 200 years, introduced species of plants, animals and micro-organisms have caused dramatic and irreversible changes to the natural ecology. They range in size from the Asian buffalo to disease-causing viruses. Introduced animals such as the fox, cat, rabbit, goat and pig have been directly or indirectly responsible for many of AustraliaÆs native mammal extinctions. Exotic fish such as the European carp and trout have damaged freshwater environments. Introduced plants such as \IMimosa\i and rubber vine are taking over large tracts of land and waterways. An introduced fungus, \IPhytophthora cinnamomi,\i is a major cause of dieback, a disease threatening whole ecosystems.
\BAustraliaÆs people\b
The first humans arrived in Australia at least 50,000 years ago. Prehistorians believe that they came from the north, through south-east Asia, probably at a time when sea levels were lower than now and sea voyages shorter. Waves of migration probably occurred over thousands of years. By about 20,000 years ago, people had spread to all parts of Australia.
The early Australians did not use agriculture. The persistence of hunting and gathering may well have been an adaptation to the low productive potential of most of the country. The people clearly knew a great deal about the landÆs resources and how to care for certain plants.
Like all people, they modified their environment to suit their needs ù mainly through the use of fire. It is possible that continuous hunting, coupled with vegetation changes resulting from regular burning, drove some animals to extinction and changed the species composition of the fauna.
With the arrival of Europeans just over 200 years ago, the rate of human-induced environmental change accelerated dramatically. Sent in the belief that the land had boundless potential, the first European settlers found the environment harsher than anticipated, and both it and the original inhabitants soon came to be seen as generally hostile and alien. Introduced disease, especially smallpox, and violent conflict had a devastating impact on the indigenous people.
As the newcomers colonised more and more land ù clearing it and introducing European agricultural practices and exotic plants and animals ù the prevailing view changed from early dismay to unrealistic expectations. The environment could be ætamedÆ to create great wealth. As the colony prospered, visions grew of a wealthy and powerful nation, rivalling the United States.
Only much later did people begin to realise that AustraliaÆs environment has many limitations, and that its ædevelopmentÆ has come at great cost.
\BDescription:\b Lord Howe Island \I(Colin Taylor)\i
Sustainable development is arguably the central issue of our time. Its basic aim is to meet the needs of the present without compromising the ability of future generations to meet their own needs. Support for this goal is now widespread. Following extensive consultation with all community sectors, Australian governments adopted in 1992 a National Strategy for Ecologically Sustainable Development (ESD).
The strategy defines ESD as a pattern of development that improves the total quality of life, both now and in the future, in a way that maintains the ecological processes on which life depends. One of the functions of this report is to assess progress towards the goal of ecological sustainability.
\BInformation needs\b
State of the Environment reporting is an important step in the essential process of refining the knowledge base on which decisions about the environment are made. That base is currently inadequate. For example, while we believe that more than 90 per cent of vertebrates and higher plants in Australia are identified and described, it is estimated that only about 50 per cent of the invertebrates and simpler plants are identified. We know even less about other species such as fungi and bacteria. With such limited knowledge, it is impossible to assess the impact of human activity on biodiversity ù a critical aspect of ecosystem health and resilience.
Australia lacks the integrated national systems and databases to measure environmental quality, manage it and evaluate the effectiveness of that management. Until these deficiencies are rectified, we will remain unable to truly answer the question of whether our pattern of development is genuinely sustainable.
Our lack of knowledge and understanding of environmental issues emerges again and again in the report as a major obstacle to sound environmental management.
\BWhat we need to sustain\b
Sustainable development requires the maintenance of the following three key components of the environment:
ò \Ibiodiversity:\i the variety of species, populations, habitats and ecosystems
ò \Iecological integrity:\i the general health and resilience of natural life-support systems, including their ability to assimilate wastes and withstand stresses such as climate change and ozone depletion
ò \Inatural capital:\i the stock of productive soil, fresh water, forests, clean air, ocean, and other renewable resources that underpin the survival, health and prosperity of human communities
\BGlobal environmental context\b
We now recognise that we are part of a global ecosystem and an increasingly integrated global economy. This poses a new set of questions for sustainable development. Issues such as ozone depletion and climate change demand global responses. International action is succeeding in reducing the use of ozone-depleting substances. Halting and reversing the trends in greenhouse gas emissions will be much harder, requiring a fundamentally different approach to the use of energy.
Agenda 21 ù a program of action for sustainable development worldwide ù was adopted in 1992 by more than 178 governments, including Australia, at the UN Conference on Environment and Development. It highlights the pressures on the natural environment from population growth and associated poverty in the developing world, and unsustainable patterns of consumption in the industrialised world. Increasing global pressures to reduce resource consumption and waste production are a part of AustraliaÆs future.
There are various indications of global environmental stress. More than two-thirds of the worldÆs bird species are in decline, vulnerable or threatened with extinction. Frog populations appear to be declining, although it is uncertain why this is happening. Coral reefs appear to be in trouble. Globally, key indicators of food production per head are falling, including production of beef and mutton, cereals and seafoods.
\BThe Australian environment: constraints and driving forces\b
AustraliaÆs natural environment is a product of its geological history and the manifold impacts of human activity. Any analysis of the state of the environment has to begin from an appreciation of the unique geological, physical and biological characteristics of the country which constrain our actions. It has also to consider the driving forces which are altering the state of the natural world, including population size and distribution, and the patterns of human activity.
Australia is an old, weathered, eroded landscape, flat and generally dry, with a highly variable climate, especially rainfall. Its unique plants and animals reflect its long isolation from other land masses and their wildlife.
The population of Australia when Europeans arrived is estimated to have been between 300,000 and 1.5 million. Seventy years later, the European population had reached one million. By 1995, the total population stood at 18 million. Adding to the environmental pressures created by the increasing permanent population is the growing influx of tourists, who are often attracted to our most precious natural and cultural heritage areas. Other factors that influence our impact on the environment include the distribution of people (Australia is one of the most urbanised of all nations, with most people living in a few large coastal cities), our lifestyles and our use of technology.
For at least 50,000 years, people have lived here and modified the environment, harvesting its biological resources, using fire to alter it, changing its shape and imposing their patterns of settlement. Since 1788, the human impact has increased dramatically, because of both the rapid growth in population and the introduction of farming, forestry, mining and large towns and cities.
Climate variability has been a constant problem for Australians because it causes natural fluctuations in vegetation and fauna. It is not this variability, or other features such as the poor soils, that puts pressure on our environment, but human activities that fail to take sufficient account of these features.
Two fundamental difficulties hinder the development of appropriate responses to environmental problems. First, we may not know the cause or causes, which can involve a complex interaction between a variety of factors; and second, there can be a long time lag between changes in human activities and any observable differences in natural systems.
Even where we are clear about the problems and what needs to be done, our institutional arrangements ù such as those between and within governments ù make it difficult to deliver coordinated responses.
\BDescription:\b Russell Falls, Tasmania \I(DFAT)\i
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"Key Issues for Improving the Environment",3,3_0029.jpg,c,0
\BA systems perspective\b
Our responses need to embrace a systems approach that reflects the complexity of the natural world and the cultural values associated with it. There is little likelihood of a coherent policy emerging from the traditional compartmentalised approach in which different departments or different levels of government each handle different, small parts of the problem.
\BBiodiversity\b
Biodiversity is the variety of all life forms: the different plants, animals and micro-organisms, their genes and the ecosystems of which they are a part. Australia has one of the widest ranges of biodiversity of any nation, with a large proportion of its species found nowhere else in the world. The major threats to biodiversity are: land clearing; loss of native forests; introduced species; the absence of some representative ecosystems in national parks and other reserves; and the lack of knowledge about our biodiversity.
\BWater\b
How we use the land affects the state and use of inland waterways, which in turn affect estuaries and the sea. A systems approach is essential: land management is more likely to be effective if it is based on biophysical regions, water management on integrated catchments, and oceans on an integrated approach to marine ecosystems. Water-related issues include scarcity, quality and nutrient loads, waste water disposal, rising groundwater and associated salinisation, and pollution of coastal waters.
\BLand degradation\b
There is widespread concern about the degradation of farm land. Pressures include clearing, over-stocking, cropping on marginal land, irrigation, and introduced species such as rabbits and goats. These pressures lead to a range of problems including erosion, salinisation, acidification, waterlogging and poor soil structure.
\BGlobal climate change\b
Global warming and other climatic changes which result from increased emissions of greenhouse gases pose a serious problem, both in terms of the direct impacts and the potential to aggravate other environmental problems such as biodiversity loss. While AustraliaÆs total emissions of greenhouse gases are small in global terms, our per capita emissions are among the highest in the world. We do not appear to be making much progress in stabilising, let alone reducing, these emissions.
\BThe urban environment\b
While the environmental problems of our large cities may be less serious than those of many smaller settlements in terms of the impact per person, they are among our most important environmental concerns because of the scale of human activity these cities represent.
\BSocial and cultural issues\b
The biophysical environment is imbued with cultural significance and encompasses the dwellings and settlements in which we live. The four key social and cultural issues are: various forms of social stress such as emerging pockets of poverty and high unemployment; the loss of physical and cultural well-being of many indigenous Australians; the loss of cultural continuity under conditions of rapid change; and the inadequate protection of heritage.
These issues can affect the natural environment as well as being important in their own right. One criterion for sustainable development is social integrity; for this reason alone, social problems deserve attention. In the case of the first of the four key social and cultural issues a growing number of æpockets of povertyÆ pose potential problems for the social environment, and a reduction in the size of households is contributing to urban sprawl. The other three issues expose inadequacies in the conservation of our natural and cultural heritage. Losing our past makes it more difficult to evaluate our future. Sustainable development will only be possible if it is firmly based on our natural and cultural heritage.
"Overview of the State of the Environment",4,2_0055.jpg,c,0
\BThe good news\b
In some areas AustraliaÆs environment is not threatened, and is in relatively good condition, especially compared with most other parts of the world.
ò Unlike most industrial nations, we have no significant problem with sulphur dioxide and acid rain. Levels of some urban air pollutants, including lead, carbon monoxide, nitrogen oxides and large particulates, have declined in recent years.
ò Urban drinking water quality is generally very good, as is the standard of our food, with low levels of chemical residues and metals.
ò Oceans and estuaries, away from major cities and developed coastal areas, are in relatively good shape.
ò Our urban housing is generally of good quality, and a well-established system exists for protecting significant places.
\BThe bad news\b
Elsewhere, however, we are experiencing serious environmental problems.
ò The loss of biological diversity is perhaps our most serious environmental problem. Whether we look at wetlands or saltmarshes, mangroves or bushland, inland creeks or estuaries, the same story emerges. In many cases, the destruction of habitat, the major cause of biodiversity loss, is continuing at an alarming rate.
ò In cities, transport systems, stormwater and sewage and other waste disposal continue to have substantial adverse impacts on the environment, including biodiversity and water quality.
ò Inland waters in southern Australia are in poor shape, largely because of poor management. Too much water is being taken from some systems, and nutrient and salt levels are of concern. Algal blooms may be becoming a more serious problem. In northern Australia, there is still time to prevent deterioration.
ò The hole in the protective ozone layer over the Antarctic is growing larger and deeper, exposing humans and other species to increased levels of harmful ultra-violet radiation. Present indications suggest that the layer will slowly recover.
ò Soil erosion from agricultural land remains a problem, especially given our poor, shallow soils and low rates of soil formation. Other forms of degradation, such as salinisation, are also not being adequately addressed. The continuing productivity of our agriculture may be at risk.
ò Some aspects of the environment experienced by indigenous Australians remain poor. Indigenous people have not shared the improvements in health enjoyed by other Australians over the past 50 years. Their health remains a serious problem that is yet to be adequately addressed. The loss of traditional indigenous languages has been profound. Both these issues are important to our cultural heritage.
ò Old growth forests continue to be logged.
\BThe uncertainties\b
In a number of areas there is not enough information to assess the situation. Some areas warrant concern rather than alarm.
ò The status of some marine species, including mammals, reptiles and some types of fish, is of concern.
ò Some types of forest are threatened with disappearance and we cannot be certain that others are adequately protected to ensure their survival.
ò Our system of reserves is patchy, with areas of poor biodiversity being better protected than areas of high biodiversity, because the poorer areas also have less economic value.
ò For a range of issues, including aspects of urban air quality, water systems and natural and cultural heritage, the available data do not permit a clear description of the national picture.
\BDescription:\b Forest workers \I(DFAT)\i
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"Australia's Responses to the State of the Environment",5,01240034.jpg,c,0
AustraliaÆs response to the state of its environment has been effective in some areas, in others questionable, and in yet other areas, either inadequate or counter-productive.
\BCommendable actions\b
Australia is doing well ù in some cases setting an international example ù for a range of issues.
ò The listing of natural areas and cultural landscapes under the World Heritage Convention, and their subsequent protection, is a real success story, as is the increasing provision for other forms of reserve status, and the strengthening of State and Territory heritage legislation.
ò Some of our structural solutions to complex management problems, such as the Great Barrier Reef Marine Park Authority, the MurrayûDarling Basin Commission and the Board of Management of Uluru-KataTjuta, are recognised internationally as good models of response.
ò The recent decision to limit further diversion of water from the rivers of the MurrayûDarling Basin is a landmark in Australian water management. An interim cap is in place and a final cap will be made by 30 June 1997. However, in many cases water diversion remains above acceptable levels.
ò New Fisheries Acts have recently been introduced throughout Australia with the aim of managing resources within the principles of ecologically sustainable development and economic efficiency in the face of increasing fishing pressure. This has resulted in much improved management, but it is too early to judge the effectiveness for those species which were over-fished.
ò The Landcare program has been very successful in mobilising land-owners and communities to improve environmental conservation and encourage the adoption of sustainable land-use practices. The program needs to be broadened to embrace a more integrated, systems approach.
ò Australia has taken prompt and purposeful action to phase out ozone-depleting substances such as CFCs. This action puts us ahead of international targets. We have also accelerated the transition to unleaded petrol.
ò State governments, notably Queensland, Western Australia and South Australia, are acting to increase the use of renewable energy such as solar power.
ò Recycling schemes have dramatically reduced the volume of waste in some areas; the Better Cities demonstration programs, water efficiency appliance schemes, the CommonwealthÆs National Pollutant Inventory and Cleaner Production are, like many other initiatives, helping to improve environmental standards.
\BQuestionable actions\b
Another group of responses is questionable.
ò The short-term economic objective of reducing the price of power presently drives reform of the electricity industry. With this goal, energy use ù and so pollution and greenhouse gas emissions ù is likely to increase.
ò The move to regulate aircraft noise by taxation and legislation is a positive step, but only came after widespread public concern about the noise levels associated with the new runway at Sydney airport.
\BPoor responses\b
Finally, there are areas where our responses seem inadequate or counterproductive.
ò The national ability to manage the environment is continually hamstrung by structural problems between different areas of government. Standards vary from State to State, and State and Commonwealth governments frequently battle over environmental issues. The recently established National Environment Protection Council will address some of these issues.
ò Adequate measures are not yet in place to combat the threats to biodiversity.
ò Concerns remain about whether the changes to fisheries management are enough to reverse the decline in some fish stocks.
ò Despite the commitment to ecologically sustainable development, some government agencies still see their primary role as promoting economic development, with little regard to environmental costs.
ò While land clearing is restricted in some States, in others it continues to be tolerated and even encouraged.
ò Urban planning in general, and transport planning in particular, are still problems, with few effective attempts to contain urban sprawl or discourage the use of private cars. There is no concerted attempt to redirect our pattern of energy consumption in a sustainable direction.
ò Australia is falling short of its greenhouse gas emission reduction targets. In recent years, energy-related carbon dioxide emissions have grown much faster than the OECD average.
\BConclusions\b
Environmental awareness has increased dramatically in the past decade, penetrating all sections of the community. There is now ready acceptance of national and international environmental standards. Environmental management is growing rapidly, as a profession and a practice. However, we do not yet have an integrated, system-based approach to the management of natural resources. Until we do, environmental management will be characterised by \Iad hoc\i responses to urgent, emerging problems. Despite the adoption of national strategies for ecologically sustainable development and conservation of biological diversity, there is little evidence that this broader approach and commitment to sustainability has been fully integrated into decision-making.
Overall, economic planning appears to take little account of environmental impacts. It is assumed that the first priority should be a healthy economy, and that problems can always be solved using the wealth created. The economy is a subset of human society which, in turn, is part of the environment. Progress towards sustainability requires recognition of this fundamental truth, and a willingness to build environmental thinking into our economic planning.
The Commonwealth government now requires sustainable infrastructure plans for all new developments involving Commonwealth funding. The provision of infrastructure and services ù power, communication and transport, water and sewerage etc. ù helps to shape the patterns of settlements, including city structures and regional development.
The plans evaluate the provision of infrastructure and services in settlements in terms of their impact on environmental indicators. Such plans could become part of standard urban development practice. They can be applied in a number of situations:
ò Large growing cities ù to enhance development processes such as reurbanisation and suburbanisation; transport and information infrastructure planning that integrates economic, ESD and social justice objectives; affordable housing, especially in the æpockets of povertyÆ emerging in Australian cities; and social and economic infrastructure, such as education and employment programs in poor areas.
ò Provincial towns ù to facilitate the move of industrial processing to regional towns where there are economic and environmental gains.
ò Coastal areas ù to address the ecological pressures of the rapid growth of coastal settlements and ascertain where net economic and environmental gains exist in further coastal development.
ò Declining rural areas ù to reverse rural decline and to move towards regional economic development based on restructuring and diversification.
ò Remote areas ù to improve provision of infrastructure to remote settlements, especially indigenous communities; to increase economic involvement in growth industries; and to improve social amenity and health.
Initiatives to reduce the metabolic flows of Australian settlements and also improve their livability often require a holistic approach because they have to be considered or adopted by a wide range of government agencies and other organisations. This applies particularly to State of the Environment reporting for human settlements, as it extends across so many different areas of responsibility.
Australia is a highly urbanised nation, with about 85 per cent of its population living in towns and cities of 10,000 or more people. Although these settlements occupy less than one per cent of the countryÆs total land area, they have a pervasive influence on the natural environment.
Australian settlements have high livability by international standards and, in general, it is improving. However, these patterns vary considerably between and within settlements.
Our settlements have higher metabolic flows ù that is, they use more resources and produce more wastes ù than those in other industrial nations. These flow levels have been increasing, both in total and per person, over the past few decades, as illustrated by the following examples.
ò Domestic water consumption has risen significantly over the past 20 years because of the rising population and increasing use per head. SydneyÆs total consumption per head (domestic and industrial) rose 25 per cent between 1970 and 1990, from 144 to 180 tonnes.
ò AustraliaÆs primary energy consumption per head increased by 37 per cent between 1970 and 1990, and its energy consumption per unit of GDP has fallen only marginally since 1970, while some other countries have reduced theirs by more than 30 per cent.
ò Food consumption per head (measured by energy content) increased by more than 70 per cent between 1967 and 1992, not because we ate more, but probably because of more energy-intensive production and more wastage in processing.
ò Australia produces more municipal solid wastes than other industrial nations ù 681 kg per person per year, compared with an OECD average of 513 kg.
\BCities\b
The big cities are generally more efficient in their metabolic flows than smaller cities and country towns. The large cities also tend to enjoy better livability. This suggests there is little to be gained environmentally by dispersing urban populations into other areas, especially the non-urban coastal zones, which are growing rapidly. Much can be done to reduce metabolic flows while further improving livability within cities.
On the other hand, the large cities, notably Sydney, are experiencing æcapacityÆ problems associated with photochemical smog, stormwater and waste water that demand changes if the cities are to continue to grow. Global constraints must also be faced, especially those arising from the greenhouse effect.
Within the large cities, the more compact core and inner areas consume fewer resources and produce less waste per head than outer and fringe areas, although there are some pressures on their infrastructure. Livability levels are similar across each large city, except the urban fringe, which suffers poorer social amenity (access to public transport, and health, educational, sporting and recreational facilities etc.).
Livability is declining in emerging æpockets of povertyÆ found right across the city. Unlike many cities in the United States, which have deteriorating cores, Australian cities are undergoing simultaneous processes of suburbanisation, with new suburbs being created at the fringe, and reurbanisation, with older areas being redeveloped. Suburbanisation is still dominant in terms of population numbers, but reurbanisation now accounts for more than 30 per cent of housing and 50 per cent of commercial development.
\BTowns\b
The urban fringe and coastal areas, particularly in northern New South Wales and Queensland, are expanding more rapidly ù and less sustainably ù than other settlements. This is evident from their metabolic flows, their pressure on sensitive environments and their livability.
Many inland towns are stagnating economically, many face significant æcapacityÆ problems with water and waste management, and are generally starved of adequate technological investment because of their limited growth potential.
The populations of the more remote provincial towns ù apart from tourist centres ù are declining, and this is reflected in their reduced livability. It suggests that population decline is not good for settlements that need investment and community commitment to address long-term environmental and livability problems. Diversifying the productive base is an economic, social and environmental priority.
\BRemote settlements\b
The number of remote indigenous communities is growing. They have low metabolic flows, but face some æcapacityÆ issues (for example, firewood). They also have extremely low livability on all indicators, particularly health. Powerful cultural forces have driven this æreturn to the countryÆ, which is only now being helped by appropriate technology. The communities lack basic infrastructure, as well as social and economic development programs to improve livability.
\BManagement\b
Australian settlements are falling well short of the environmental objectives expressed by governments. Increasing use of resources per head, growing population, and patchy implementation of the legislative, social and technological innovations necessary to ameliorate the environmental impact of settlements, all contribute to this situation.
The new technique of sustainable infrastructure planning, which evaluates the environmental impact of infrastructure and services, together with innovative Commonwealth government programs such as Better Cities and Cleaner Production, can reduce metabolic flows in all Australian settlements and increase their livability.
\BDescription:\b Construction site \I(Webster Publishing)\i
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"Biodiversity",7,acacia36.jpg,c,0
Biodiversity is the variety of all life forms, and comprises the different plants, animals and micro-organisms, their genes and the ecosystems of which they are a part.
Life in Australia has evolved in relative isolation for at least 50 million years. As a result, Australia possesses a rich diversity of unique and unusual plants, animals and micro-organisms.
About 85 per cent of flowering plants, 84 per cent of mammals, more than 45 per cent of birds, 89 per cent of reptiles, 93 per cent of frogs and 85 per cent of inshore, temperate-zone fish are endemic to Australia ù that is, they are found nowhere else in the world. While a majority of these species have been studied, relatively little is known about the vast and less visible world of invertebrate animals and micro-organisms. In all, Australia is home to more than one million species, but less than 15 per cent have been described.
We depend on biodiversity for our survival and quality of life. The most significant impediment to the conservation and management of biodiversity is our lack of knowledge about it and the effects of human population and activities on it.
Preserving AustraliaÆs biodiversity is important for four reasons:
ò \IEcosystem processes:\i biodiversity underpins the processes that make life possible. Healthy ecosystems are necessary for maintaining and regulating: atmospheric quality, climate, fresh water, marine productivity, soil formation, cycling of nutrients and waste disposal.
ò \IEthics:\i no species ù and no generation ù has the right to sequester EarthÆs resources solely for its own benefit.
ò \IAesthetics and culture:\i biodiversity is intrinsic to values such as beauty and tranquillity. Many Australians place a high value on native plants and animals, which contribute to a sense of cultural identity, spiritual enrichment and recreation. Biodiversity is central to the cultures of Aboriginal and Torres Strait Islander peoples.
ò \IEconomic:\i Australian plants and animals attract tourists and provide food, medicines, energy and building materials. Our biodiversity is a reservoir of resources that remains relatively untapped.
\BDescription:\b Australia's wattle.
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"Pressures on Biodiversity",8,16_0041.jpg,c,0
\BPressures on biodiversity\b
The demands on natural resources arising from increasing populations of humans and their industrial and other activities give rise to a range of pressures on biodiversity, including the following examples.
\IHabitat modification\i
Australia has developed very rapidly (in some regions taking 200 years to achieve what took 10,000 years in other parts of the world). Since European settlement, almost 70 per cent of all native vegetation has been removed or significantly modified, including the loss of about 40 per cent of total forest area and 75 per cent of rainforests. As much land was cleared over the last 50 years as over the previous 150 years. Native vegetation is being cleared at a rate of more than 600 000 hectares per year ù about half the rate of clearing in the Brazilian Amazon in 1990û91.
\IIntroduced and dispersed species\i
These exert a major pressure on biodiversity. They eat native fauna and flora and compete with native species for habitat. They include exotic organisms, such as species introduced for production purposes, weeds, feral animals, introduced disease organisms, and native species whose range and abundance have changed.
Introduced plants present an acute ecological problem. They account for about 15 per cent of the total flora and about one-quarter of them either are, or having the potential to be, serious environmental weeds. These include rubber vine, blue thunbergia, two semi-aquatic grasses, para grass, giant sensitive plant and athel pine. The rubber vine, for example, entangles trees and other vegetation, eventually smothering them. It is spreading through the river systems of Queensland, destroying riverside vegetation at an alarming rate.
At least 18 exotic mammals have established feral populations in Australia, including cats, dogs, foxes, rabbits, pigs, water buffalo, donkeys, goats and horses. Cats and foxes have been blamed for the decline, and possibly the extinction, of several native animals. For example, studies of the red-tailed black cockatoo in Western Australia showed that feral cats caused the failure of up to 20 per cent of nests by climbing into tree hollows to prey on nestlings. Exotic fish such as the trout and European carp have also caused widespread damage.
Introduced invertebrates have attracted little attention because they are small and little is known about their impacts. However, some are both obvious and destructive. For example, the European wasp, first seen in the Sydney area in 1978, has spread widely. It preys on native insects, including commercially important pollinators, and attack soft fruits. In Europe, colonies are generally annual, and the onset of winter kills all the wasps except the queens, which start new colonies each year. In Australia, with its warmer winters, the colonies have become perennial, growing very large with huge numbers of wasps
Introduced species can carry diseases that infect native species. For example, the introduced fungus, \IPhytophthora cinnamomi\i causes the disease, dieback, that is devastating many native trees in some parts of Australia. The disease can kill 80û100 per cent of infected individuals in susceptible groups such as Banksias and Grevilleas, threatening entire ecosystems.
Some native species are spreading or becoming more abundant because of clearing, cropping, grazing and other activities. These may be as serious a threat to biodiversity as exotic species. For example, much of the pastoral land in the central-western areas of New South Wales and Queensland have become densely infested with woody weeds ù shrubs that occur naturally but have spread at the expense of other natives because of overgrazing and changed fire patterns.
The galah has spread over much of Australia because of the creation of vast areas of suitable habitat (grasses, cereal crops and abundant water), bringing it into competition with other birds. CarnabyÆs Cockatoo, a black cockatoo of south-western Australia, has disappeared from a third of its range in the past 25 years; competition from galahs over nest sites has contributed to its decline.
\IPollution\i
This is an actual and potential threat to biodiversity, particularly in regions close to industrial sites and urban areas. Pollutants include heavy metals and hydrocarbons in urban stormwater, and fertilisers, insecticides and herbicides in run-off in rural and inshore areas. For example, sewage effluents and agricultural run-off are high in nitrogen and phosphorus, but low in silica. This has resulted in a major shift in species composition in some marine areas from a plankton community dominated by diatom algae, which need silica, to one dominated by dinoflagellate algae, which do not. Dinoflagellate blooms cause a range of serious problems, from massive fish kills associated with æred tidesÆ to paralytic shellfish poisoning in humans.
\IMining\i
Mine operations, both terrestrial and marine, are numerous, but generally involve a small area. However, their local impact on biodiversity can be intense. Long-term and extensive operations such as open-cut coal mines and mining of coastal sand dunes have severe impacts on local biodiversity.
\IClimate change\i
The habitats of many of AustraliaÆs endangered vertebrates may contract significantly if the climate warms. Under one scenario, 46 of the 57 endangered species would contract in range. However, it is difficult to assess the impact of climate change on biodiversity because it depends largely on the rate of change and the compounding effects of other pressures such as habitat loss and fragmentation.
\BImpacts\b
Every ecosystem in and around Australia, with the possible exception of the deep ocean, has been modified in some way, with varying impacts on biodiversity. However, there is limited information on which species were present when Europeans arrived here, which are present now and which have been lost. It is difficult to respond to the pressures and the changes in the state of biodiversity without basic information on what that state is and how biodiversity is distributed.
For the land animals and plants about which we know enough to assess their current state, the trends are disturbing. Some 5 per cent of higher plants, 23 per cent of mammals, 9 per cent of birds, 7 per cent of reptiles, 16 per cent of amphibians and 9 per cent of fresh-water fish are extinct, endangered or vulnerable. Australia has the worldÆs worst record of mammal extinctions. In the past 200 years, we have lost 10 of 144 species of marsupials and 8 of 53 species of native rodents.
\BManagement\b
Since the 1980s, several major international agreements have addressed biodiversity as a key issue. It has become an important organising principle in a number of national policy statements, and is now influencing decision-making at national, State and regional levels. In particular, the Commonwealth, State and Territory governments have endorsed the National Strategy for the Conservation of AustraliaÆs Biological Diversity to guide the implementation of policies related to biodiversity.
However, governments are not providing enough resources to give effect to these policies. A lack of coordination between Commonwealth, State and local government is also a major impediment.
Australia is one of 12 nations in the world that contain major repositories of biological diversity. It is the only one that is industrially developed, has a relatively small human population, and occupies an entire continent. Thus we have a good opportunity, as well as the responsibility, to balance conservation, human population growth and demands, and economic development.
This can only be done by making substantial changes to the way we manage the land and ocean. Many current practices are not sustainable, and biodiversity-based industries such as agriculture, pastoralism, forestry, fisheries and tourism often erode the very resources upon which they depend.
Australia lacks major, co-ordinated programs for the discovery, monitoring, management and sustainable use of biodiversity. New strategies, particularly ecologically sustainable development, give us the opportunity to provide world leadership in the wise use of natural resources, including their conservation for future generations. Without this comprehensive approach, the future is bleak for much of AustraliaÆs unique flora and fauna.
\BDescription:\b Australian grebe \I(QDEH)\i
#
"Atmosphere",9,2_0073.jpg,c,0
The atmosphere makes life on Earth possible. Without it, or with a changed atmosphere, conditions on the planet would be very different. Not only is it essential for life, it is important to the quality of life: clean, fresh air adds to our sense of well-being.
Pressures on the atmosphere are created mainly through the emission of gases and other substances into the air.
Most of our atmospheric emissions result from burning fossil fuels for transport, power generation and industrial production. Many industrial, commercial and domestic processes also emit waste gases. Agriculture is a source of emissions, and affects the atmosphere indirectly ù clearing vegetation, for example, increases carbon dioxide emissions and decreases its absorption.
The size and growth rate of the human population, the industrial and resource base, economic growth and lifestyles all influence the demand for energy and other resources, and so the level of emissions. For urban areas, the impact of these emissions is affected by the location of the major cities in coastal areas where a natural recirculation of polluted air sometimes occurs.
\BGlobal issues\b
Global issues result from long-lived emissions that become well-mixed through the global atmosphere ù for example, the enhanced greenhouse effect and the loss of stratospheric ozone.
\IThe enhanced greenhouse effect\i
Human activities are substantially increasing the atmospheric concentrations of a range of so-called greenhouse gases. These include carbon dioxide, methane, (tropospheric) ozone, nitrous oxide and chlorofluorocarbons (CFCs). Since pre-industrial times (since about 1750), the concentration of carbon dioxide has increased by more than 30 per cent, and methane by more than 145 per cent.
Greenhouse gases absorb infrared radiation emitted by EarthÆs surface and so keep the planet warmer than it would otherwise be. Climate models suggest that increases in atmospheric concentrations may lead to global warming because of an enhanced greenhouse effect. The models suggest an increase in the global surface temperature, relative to 1990, of about 2░C by 2100. Many uncertainties remain about the timing, magnitude and regional patterns of climate change. Nevertheless, the balance of evidence suggests that humans have a discernible influence on global climate.
Unless large reductions in emissions occur, the concentrations of most greenhouse gases will continue to rise well into the next century. Models indicate that carbon dioxide levels will more than double unless global emissions are reduced to well below 1990 levels. Australia produces between one and two per cent of global greenhouse emissions, which come mainly from fossil-fuel burning, land-clearing and agriculture.
Initiatives to reduce emissions under the National Greenhouse Response Strategy (NGRS) have achieved limited success. The Greenhouse 21C program includes cooperative agreements with industry and has the potential to bring about reductions in greenhouse gas emissions, though not of the magnitude required to achieve the goals of the NGRS. It is too soon to judge the success of this program.
\IOzone depletion\i
CFCs, together with some other chemicals, have been implicated in another important global phenomenon ù the depletion of ozone in parts of the stratosphere, which increases levels of damaging ultraviolet (UV) radiation at the earthÆs surface.
Losses of stratospheric ozone of between two and four per cent per decade have occurred in mid-latitudes since the 1950s, including over Australia. More dramatic, has been the emergence in the 1980s of a æholeÆ in the ozone layer over Antarctica each spring, in which more than 60 per cent of the total ozone is now destroyed over a region covering most of the continent.
Concentrations of CFCs are now levelling off, following the implementation of international controls. Australia has reduced production and use of ozone depleting substances well ahead of international obligations and plans are in place for further reduction. However, because of time lags, ozone depletion will continue to worsen for several years, and UV radiation will increase. Current trends suggest that the ozone layer should begin to recover at the beginning of the next century.
\BRegional air quality\b
Pollutants such as vehicle and industrial emissions last long enough to have effects far from their sources ù for example, photochemical smog and brown haze.
Air quality is not monitored over 95 per cent of the continent. Certain important point sources of air pollution exist away from the major cities ù mainly power stations and metal smelters. The main pollutants from these sources are sulphur dioxide, fluoride and lead. The largest single sources of sulphur dioxide occur in arid areas, where dry deposition of sulfate aerosols takes place downwind of the source.
Away from these major sources, air quality is probably good. However, it is difficult to assess trends because of the natural variability of the climate and because changes in demand for metals will affect smelting operations and hence emissions.
\IUrban areas\i
Motor vehicles are the single most important source of air pollution in cities. In general, the concentrations of common pollutants meet official health guidelines and are low by world standards.
Over the last decade, some aspects of air quality in cities like Sydney and Melbourne have improved. Atmospheric lead levels have declined significantly in recent years due to legislation, pricing measures and voluntary actions by industry. Important initiatives include the mandatory use of catalytic converters and unleaded petrol in motor vehicles manufactured or imported since 1986, the price differential between leaded and unleaded petrol, and a reduction in the lead content of leaded petrol.
Levels of some pollutants, especially carbon monoxide and lead, are likely to fall further. In the short term, a similar trend is expected in smog levels (from emitted nitrogen oxides and hydrocarbons), but this may be countered by increasing vehicle use linked to population growth, urban design and possible deterioration of catalytic converters. In areas of rapid growth, such as south-east Queensland, Perth and western Sydney, vehicle emissions will remain a major concern.
Sulphur dioxide is not a major pollutant in urban areas because of the low sulphur content of Australian fuels and the location of most power stations outside the cities.
Major pollution problems in Australian cities are episodic rather than continuous, being influenced by seasonal and meteorological factors. Depending on local terrain and air flow patterns, pollutants may remain relatively undispersed as air recirculates. AustraliaÆs generally sunny climate promotes the formation of ozone and photochemical smog. As a result, air pollution levels in Sydney and Melbourne, particularly for ozone, can approach those in cities such as New York and Tokyo on some days. PerthÆs air quality is considered to be approaching the limits of its airshed.
High concentrations of fine particles in the air can reduce visibility, and endanger health. Sources include motor vehicles and woodfires, but pollen, sea salt and silica from soil also contribute to particulate levels. Levels in major Australian cities have generally declined over the past decade or so because of tighter emission controls and bans on backyard burning.
Air toxics emitted by motor vehicles ù mainly volatile organic compounds and metallic compounds ù are an emerging issue that may need further investigation.
\BLocal air quality\b
Some pollutants are contained, or rapidly dispersed or inactivated. Odour and smoke arising from traffic, intensive agriculture, wood stoves, backyard incinerators, and even cooking, can be important local issues.
\IIndoor pollution\i
An important local air quality and human health issue is indoor pollution, which can include: house dust mites; tobacco smoke; toxic compounds including insecticides; legionella bacteria in airconditioning systems; and inadequate ventilation and volatile irritants from furnishing and equipment (creating æsickÆ buildings).
\BManagement\b
It is impossible to provide a comprehensive, quantitative assessment of AustraliaÆs air quality for national SoE reporting. Issues include:
ò lack of a consistent national set of ambient air quality standards
ò often inadequate monitoring in major cities
ò lack of monitoring outside the major cities
ò fragmented and inaccessible data
ò inadequate understanding of Australian conditions
ò lack of data on the effects of air quality on flora and fauna
ò lack of a clear relationship between air quality and human health effects
ò inadequate assessment of indoor air quality and health effects
\BDescription:\b Gases released by industry contribute to the greenhouse effect. \I(DFAT)\i.
#
"Land Resources",10,01240032.jpg,c,0
The lives of many Australians, particularly indigenous people and farming families, are closely tied to the land. For the 88 per cent of Australians who live in large towns and cities, and especially those who live in the capital cities, the land is a more distant entity. Nevertheless, responsibility for the stewardship of the land is widely accepted in the Australian community.
We make many different uses of land resources, and often multiple uses of the same patch of land. Australian soils are old and relatively infertile, and rainfall is low; only six per cent of our land is arable, compared with 20 per cent of the United States. The main vegetation is woodland and shrubland.
The predominant use is extensive grazing by introduced species, which occurs over 54 per cent of the country. While the area of intensively managed agricultural land (cropping and improved pasture) is proportionally small (six per cent), it is almost twice the total area of the United Kingdom and more than the total area of Japan.
Many pressures affect the state of land resources. General pressures include: population, the failure to allow sufficiently for the poor soil and climate variability, loss of biodiversity, and economic and social pressures. Other, indirect and direct pressures include: agriculture (land clearing, fertiliser use, tillage, changes to water flows, pollution from pesticides and herbicides), pastoralism, forestry, mining, human settlement (urban expansion, tourism and recreation, and transport and utility corridors), and changed management.
\BLand cover\b
Although clearing on the scale required to establish AustraliaÆs agricultural industries is no longer occurring (it peaked in the two decades after World War II), substantial areas are still being cleared. In some wheat-growing regions, less than 10 per cent of the native vegetation remains. Clearing is an important contributor to environmental problems, especially soil salinity, loss of biodiversity, and net greenhouse gas emissions.
Since the 1980s concern about land degradation, and the decline in native vegetation, has been widespread. As a result, the Commonwealth has established a number of programs such as One Billion Trees and Save the Bush. In addition, some State and Territory governments have established legislative or regulatory controls on clearing. Although the evidence suggests that legislation has been effective in South Australia and Western Australia, there are not enough data to evaluate the effectiveness of controls in other States or Commonwealth programs there.
\BRangelands\b
Rangelands cover about 75 per cent of the country. During the early years of pastoral development stocking rates were generally unsustainable and caused major changes to vegetation and soils. Although only a small part of the rangelands (two per cent) is regarded as severely degraded, a much larger area (15 per cent) is sufficiently affected to require destocking if it is to recover. The conservation value of rangelands varies greatly. Important sites, such as water holes, are the focus of domestic and feral animal activity and are seriously damaged. The Commonwealth, States and non-government organisations are developing a National Strategy for Rangeland Management.
\BForests\b
Before the arrival of Europeans, nine per cent of Australia was covered with forest. Of this area, 40 per cent has been cleared, mostly for agriculture, and that the same area has been affected by logging. Logging can have severe impacts on biodiversity, soil and water. The National Forest Policy Statement, agreed by the Commonwealth and the States, is intended to address the issue of sustainable forest use. Regional Forest Agreements are being established to ensure a comprehensive and adequate reserve system for forests and a report is being prepared on the state of the forests. As an interim measure the Commonwealth has established deferred forest areas with the stated intention of protecting potentially important forests and reserves while comprehensive regional assessments are completed.
\BPests and weeds\b
Vertebrate and invertebrate pests cost rural enterprises dearly. Losses occur both directly through consumption and damage to produce, and indirectly through degradation of the resource base. Since European settlement, more than 1900 new vascular plant species have become naturalised ù that is, either deliberately introduced or accidentally released. Half of these are now regarded as weeds, and more than 220 have been declared noxious weeds. The major pests and weeds include some native species that have spread and thrive in ecosystems altered by European-style land uses.
Weeds are estimated to cost Australia about $3.3 billion annually. Insects cause annual losses to primary production of about $3.1 billion. A mouse plague in South Australia and Victoria in 1993 cost a total of $65 million, including $55 million in reduced yields. Rabbits are estimated to cost Australia at least $90 million (and possibly up to $60 million) a year in lost production and reduced land values.
Many Commonwealth government agencies are involved in pest control. The Bureau of Resource Sciences runs a vertebrate pest program, which deals with pest animals in agricultural production. The Australian Nature Conservation Agency has a feral pest program, which addresses the problems of pest management for conservation purposes. Other bodies, established by the Commonwealth, such as the Australian Plague Locust Commission, deal with specific pests.
\BSoils\b
Most areas of cropland and improved pasture in Australia are affected by soil degradation. However, within these areas, its impact can vary enormously ù even from farm to farm or paddock to paddock. It is impossible to give meaningful estimates of the cost of soil degradation, which occurs in several ways.
ò \ISoil structure decline:\i the structure of many Australian soils is naturally poor or has been damaged by land uses such as tillage and over-grazing. Poor structure increases run-off and erosion and reduces productivity. It is costly to repair.
ò \IWater logging and salinity:\i water tables have risen in parts of Australia as a result of land clearing and irrigation, causing water logging and salinisation. These effects reduce productivity and encourage erosion.
ò \IWater and wind erosion:\i rates of soil erosion, even on the best managed land, may be ten times greater than rates of soil formation. On sloping lands, soil erosion poses a threat to the long-term sustainability of farming.
ò \ISoil nutrient balance:\i Australian soils are infertile, making fertiliser use an essential part of most farming systems. The continental nutrient balance is positive ù that is, more nutrients are being added than are being used or lost ù but nutrients may be accumulating in fertilised pastures while declining in more naturally fertile soils.
ò \ISoil acidification:\i acidification affects most agricultural land, leading to toxicity, poorer water and nutrient use and so lower yields. Causes include the use of fertilisers and legumes, and natural weathering. Applying lime is an effective remedy, but current rates of application are inadequate.
\BFood quality\b
Misuse of agricultural and veterinary chemicals is low in Australia, and the quality of our food compares favourably with other countries. Among the heavy metals, which can be toxic, cadmium exceeds permissible levels in a proportion of some foods including offal and some seafoods.
\BSustainability\b
The question of the sustainability of land use in Australia remains difficult to answer.
\IAgriculture\i
Agricultural yields have increased significantly this century, but land degradation could undermine past gains. Inputs of fertilisers and energy into agricultural production have increased, as has our knowledge of better agricultural practices, such as trace element supplements and minimum tillage. Future sustainability will depend upon the efficient use of inputs and continuing to improve our understanding of the landÆs productive capacity. We also need to know more about the damage to other ecosystems before we can draw firm conclusions about the industryÆs sustainability.
\IForests\i
The past 200 years have seen the widespread destruction of our forests, through clearing for agriculture and timber harvesting that, in the past, was often unsustainable. The national goal is not to allow our forest estate to be eroded further and to ensure that there is a comprehensive and adequate reserve system to protect at least 15 per cent of each of the pre-1750 forest types for conservation purposes. Stronger and more effective controls are being introduced to cover all uses and values of the remaining forests, such as timber, water catchment and recreation. However, old growth forests continue to be harvested despite several findings that this practice violates sustainability principles.
There is no clear answer to whether our use of the forests is sustainable. In one sense, the answer is that æit can beÆ. However, simple and permanent solutions are unlikely to be found; sustainable use must be achieved in the context of a continuing debate by many elements of society, each with different goals and different values.
\BManagement\b
Compared with other developed nations, Australia has only rudimentary information on the condition and productive capacity of its land resources, and the potential hazards associated with their use. This limits our ability to use land in accordance with its capabilities and to monitor trends in its condition.
There are several other major issues concerning the management of land resources:
ò Our small population means we have only limited economic and technical resources to manage a huge land area.
ò Northern Hemisphere solutions to management problems are often inappropriate, and even counter-productive.
ò We have to contend with the impacts of many introduced animals and plants on a previously isolated continent.
The Landcare Program, which is enlisting widespread community support for the sustainable use of land resources, began very successfully and may provide a model of community involvement in environmental management. However, the approach must be extended and sustained, with adequate financial and technical support, if it is to have the necessary impact on land use practices.
\BDescription:\b Flooding after rainfall \I(Jonathan King)\i.
#
"Landcare Movement",11,2_0040.jpg,c,0
The establishment and growth of AustraliaÆs Landcare movement in response to the worsening degradation of farmland has attracted international attention.
The 1980s saw increasing efforts in Australia to encourage greater rural community involvement in land conservation, as it became increasingly clear that government legislation and regulation would not control degradation unless individual land users accepted responsibility for their land management practices.
Landcare began as an initiative of the Victorian Government, with the support of the Victorian Farmers Federation. The first Victorian LandCare group was formed at Winjallok in the Wimmera in 1986. In 1988, the National Farmers Federation and the Australian Conservation Foundation proposed to the Commonwealth Government a national land management program which included funding for Landcare groups as a key element.
The GovernmentÆs Decade of Landcare plan established the National Landcare Program and set a target of 2000 Landcare groups by the year 2000; the target was passed in late 1994. More than 25,000 people are actively involved in Landcare meetings and activities.
Landcare groups contain people who want to work with others to improve the long-term health of the land. Membership is voluntary, the agenda for each group is set by the members and each group operates according to its own plan. The groups give people the capacity, within their own community, to tackle issues that seem too big for individual families.
The major challenge for Landcare is to convince all land users to adopt best management practices to ensure sustainable use of resources. This will involve widespread changes to standard methods of land management.
Expectations for the movement are high, especially when viewed in the context of 200 years of agricultural development and land degradation. The degree of its success could have wide implications for society. The Landcare movement could become a model for other æcareÆ programs that enlist stakeholder commitment to sustainable resource use.
\BDescription:\b Clean Up Australia Day \I(DFAT)\i
#
"Inland Waters",12,2_0006.jpg,c,0
Australia is the driest of the worldÆs inhabited continents. Of all continents, it has the least river water, the lowest run-off, and the smallest area of permanent wetlands. One-third of the country produces almost no run-off, while two-thirds of the average annual run-off occurs in northern drainage systems.
AustraliaÆs rainfall and stream flow are the most variable in the world, and our inland streams are naturally turbid (muddy) and saline. Few permanent, freshwater lakes exist on the mainland; where lakes do occur, they are usually shallow, salt lakes that are dry more often than not.
The largest river system is the MurrayûDarling, which drains about one-seventh of the continent. It ranks among the worldÆs biggest in terms of river length and catchment area, but carries much less water than comparable river systems ù in less than one day, the Amazon carries the MurrayÆs annual flow.
Over large tracts of inland Australia, (under)groundwater is the only practical source of water for pastoral and mining industries and local communities. The Great Artesian Basin is among the largest groundwater systems in the world.
Since the early days of European settlement, the development of water resources to support the economy and human population has been a priority. Because of our dry and variable climate, Australia stores more water per head of population than any other country in the world. Sydney stores 932 kilolitres of drinking water per person, compared to New YorkÆs 250 and LondonÆs 18.2. We are now focusing more on the environmental impacts of this development, principally through an initiative of the Council of Australian Governments (COAG) known as the COAG Water Reform Framework.
\BDrinking water\b
Water quality in large cities is generally high, but in some rural and remote communities, it is less satisfactory. Problems are usually caused by a combination of micro-organisms, chlorination by-products, taste, odour, algal toxins, iron, manganese, turbidity, salt and æhardnessÆ. Drinking water in Australia is generally free of industrial pollutants.
\BIssues\b
The diversion of water for human purposes has seriously affected the natural environment ù wetlands and rivers, in particular, need more water. The environmental stress caused by the over-allocation of water for human use and consumption is greatest along the eastern seaboard and in the MurrayûDarling Basin. Some 80 per cent of the divertible or accessible water in the MurrayûDarling Basin has now been developed for human use. Elsewhere, the environmental stress is far less severe (and absent in undeveloped areas).
Australia is effectively mining its groundwater, with reserves being used much faster than they are replenished. Groundwater is often very old, with some bores tapping water that entered the ground 1û2 million years ago.
Irrigation uses the most water, accounting for 70 per cent of all the ædevelopedÆ resource. Next come the major cities, with most of this use being domestic. Household water use has increased because of increasing populations and rising consumption per head. Industrial water use is not large overall.
A major environmental consequence of both irrigation and land clearing for dryland agriculture is salinisation ù the result of rising water tables that bring dissolved salts to surface soils and waters. In some parts of the MurrayûDarling Basin, the water table is rising by as much as 0.5 metres a year. In dryland catchments in south-east Australia, the water table has risen by up to 30 metres since the 1880s. About one-third of VictoriaÆs irrigation area has been salinised.
The irrigated agricultural industry in Victoria and New South Wales will need major restructuring to deal with the economic and environmental problems salinity causes. Dryland agriculture has increased salt loads and concentrations in many rivers in south-east and south-west Australia. About one-quarter of the cleared land in south-west Western Australia will become salinised over the next few decades, and dryland salinity will also expand in the eastern uplands of Victoria, New South Wales and Queensland.
Sediment from erosion continues to foul rivers, increase the cost of water treatment and reduce the storage capacity of dams and reservoirs. Levels of nutrients, particularly phosphorus, from run-off, erosion and point sources such as sewerage outlets, remain unacceptably high in our rivers, lakes and reservoirs. Levels of pesticides can be expected to increase in both surface water and groundwater.
\BConsequences\b
All these problems ù sediments, salt, nutrients, pesticides and, in a few cases, trace metals and organic wastes ù threaten aquatic environments. High levels of phosphorus, in conjunction with reduced stream flows, have resulted in extensive blooms of toxic blue-green algae, whose frequency may be increasing. The biological impacts of pesticides are largely unknown, but in some cases they cause more damage to aquatic species such as frogs than to the target organisms in crops.
Drainage and the loss of wetlands also threaten aquatic environments. A large proportion of wetlands have been destroyed or seriously disturbed, and the banks of most rivers have been damaged. Introduced species of aquatic plants and animals are another pressure. Exotic fish have established wild populations, often at the expense of native fish and other species. Exotic water weeds have spread in many parts of the country. The most damaging exotic species are the European carp, trout and the giant sensitive plant, \IMimosa pigra.\i
As a result of these changes to AustraliaÆs inland waters, many species of aquatic animals are endangered, in decline or already extinct. Native fish species have declined in abundance and diversity in most regions of Australia since European settlement. Some 32 species of frogs are reported to be in decline, with only limited data available on many others. The platypus is still found throughout its original range, but frequently in reduced populations.
\BManagement\b
Australia lacks basic data on water quality and catchment characteristics. Where they do exist, figures are often not collated nationally or are unavailable because of issues of ownership. Information is often of poor quality, incomplete and not comparable between agencies, localities and over time.
Most environmental and water resource organisations give low priority to high-quality monitoring of phenomena other than flow, and the technical expertise behind many monitoring programs is poor. The Commonwealth-funded National River Health Program, dedicated to developing a nationally consistent methodology for assessing the health of rivers, is a major initiative in this area. It focuses on the use of biological indicators and includes research into environmental flow requirements of AustraliaÆs rivers.
Of the key responses that would improve the condition of AustraliaÆs inland waters, the most important is catchment and water management that acknowledges the high natural variability of rainfall and run-off. Catchment management is being implemented over many systems. It is becoming more effective with increasing knowledge and is spreading around the country. The MurrayûDarling Basin Commission is the most obvious example of this approach. However, despite these gains, catchment management still lacks the technical support to meet stated goals for water quality.
\BDescription:\b Kakadu \I(DFAT)\i
#
"Groundwater - a Vital Resource",13,1_0032.jpg,c,0
Groundwater is an integral part of the water cycle, and constitutes the largest terrestrial water store ù the volume in just the upper one kilometre of the earthÆs crust is ten times that in all the worldÆs rivers and lakes.
Groundwater is inextricably linked to the surface environment. It sustains many wetlands, allows streams to flow through long dry periods and supports vegetation. It is also affected by disturbances to these surface environments.
Because groundwater lies invisible, beneath the surface, it is poorly understood and often abused. We do not appreciate its vulnerability to over-development and pollution. While there have been substantial improvements in surface water quality in many countries in the past 30 years, groundwater quality has decreased. Many countries face huge costs to clean up groundwater because of waste disposal practices that had little regard for impacts on it.
The use of groundwater has also increased, doubling in the United States since 1950. The same trends in quality and use are occurring in Australia, but we still have time to reverse them.
Management of land and water must take full account of groundwater. A key factor is the much longer time it takes water to flow through underground aquifers than across the surface in streams and rivers. For example, surface water takes only weeks to travel from the Great Dividing Range in Queensland to central Australia after flooding rains; the groundwater of the Great Artesian Basin takes about one million years to travel the same distance.
People living in 60 per cent of Australia are totally dependent on groundwater. In another 20 per cent of the country they use more groundwater than surface water.
The Great Artesian Basin, which underlies one-fifth of the continent at a depth of one to two kilometres, is the lifeblood of much of eastern inland Australia. It is recharged mainly along the western slopes of the Great Dividing Range in New South Wales and Queensland. The uncontrolled flow from bores sunk into the basin has resulted in a serious and unnecessary depletion of its water. A program of bore capping, which is underway, will gradually stem the waste, but at considerable cost.
Pollution is another concern. Because of the timescales involved in replenishing groundwater, once pollution has occurred it is virtually impossible to remove. Unfortunately, the basin recharge areas in New South Wales are also sites of major concern for groundwater contamination. The contaminants listed include total dissolved solids, metals, pesticides and nitrates; the sources are agriculture and mining.
The MurrayûDarling Basin initiative is effectively the largest integrated catchment management program in the world, encompassing 1.6 million square kilometres. The initiative promotes and coordinates effective planning and management, for the equitable, efficient and sustainable use of the BasinÆs land, water and other environmental resources.
The key to the initiative is the 1988 Natural Resources Management Strategy, which provides the philosophical and organisational structure within which the Commonwealth government and the four Basin State governments ù New South Wales, Victoria, South Australia and Queensland ù can work together with Basin communities to achieve its goals. The strategyÆs objectives are to:
ò maintain or improve water quality through research into the problems affecting catchments
ò control and reverse land degradation
ò protect and rehabilitate the natural environment
ò conserve the cultural heritage
Two funding programs support the initiative: the first covers investigations and education, and the second integrated catchment management. The former funds activities to understand and develop solutions to the BasinÆs resource management problems. The outcomes are then translated and implemented into practical on-the-ground solutions under the second program. To ensure commitment from the community, at least one-third of the funding for this work must come from the local community.
The MurrayûDarling Basin Commission is responsible for administering the initiative. The Commission answers to the MurrayûDarling Basin Ministerial Council, comprising the relevant Ministers from the Commonwealth and Basin State governments.
The development of an appropriate structure for managing the grave and worsening degradation of land and water in the Basin has been a long and painful process. The initiative brings this process to maturity ù as perhaps best demonstrated by the CouncilÆs recent, landmark decision to place an interim limit on further water diversion from the Basin rivers. A final cap on water diversion will be made by 30 June 1997.
\BDescription:\b Murray River \I(Readers Digest)\i
#
"Estuaries and the Sea",15,gbrcrown.jpg,c,0
As an island continent with a long coastline, Australia has many different marine and estuarine environments. These span a wide range of coastal types, climates, geological and biological regions. Most are far away from major population centres and are little affected by human activities. Large stretches of our coastline are among the least-polluted places on earth.
AustraliaÆs marine environments extend from its beaches, rocky shores and intertidal reefs to the boundary of its 200-nautical-mile Exclusive Economic Zone (EEZ). They include large areas of the seabed that are important for fishing, oil and gas production and possibly mining, and areas of water that, in places, are biologically highly productive. Generally, however, our marine waters are low in nutrients and therefore productivity. Our estuaries are ecologically important habitats, usually rich in nutrients and with high productivity and biological diversity.
On the whole, our marine and estuarine environments are in good condition. In areas of high population density or intense human activity, however, they are often degraded as a result of urban, agricultural and industrial development and tourist and recreational activities.
\BNutrient enrichment and sedimentation\b
The most serious issue affecting AustraliaÆs marine and coastal environments is the decline in water quality caused by rising levels of nutrients and sediments. Soil erosion, fertiliser use, intensive animal production, and sewage and other urban and industrial discharges have increased the levels of nutrients (especially phosphorus and nitrogen) and sediments entering many bays and estuaries. Other pollutants include industrial chemicals and pesticides, heavy metals, pathogens (disease-causing micro-organisms) and litter.
Each year, AustraliaÆs sewerage systems discharge about 10,000 tonnes of phosphorus and 100,000 tonnes of nitrogen, much of which enters the sea. Yet most nutrients (possibly as much as 85 per cent) come from diffuse catchment sources. Scientists have estimated that, in Queensland, the amounts of sediment, nitrogen and phosphorus entering the sea each year have increased three to fivefold since European settlement. The rivers of QueenslandÆs east coast catchments are estimated to deliver about 14 million tonnes of sediment to estuaries and coastal marine waters annually. Between Palm Beach and Cronulla in Sydney, 200 large stormwater outlets discharge water containing high levels of pollutants such as sediments, bacteria, nutrients, trace metals and organic chemicals.
High nutrient levels promote algal blooms ù some toxic. These have increased in frequency, intensity and geographic distribution over the past 30 years. They can degrade ecosystems, reduce the recreational value of waterways, affect human health and destroy aquaculture production.
The Commonwealth is cooperating with State and Territory Governments on issues such as land-based sources of marine pollution, including nutrients and sediment.
\BExotic species\b
Introduced plants and animals are damaging marine and coastal environments. Some introduced species also threaten aquaculture, and pose risks to human health. At least 55 species of fish and invertebrates, plus several seaweeds, have been introduced into Australia, either intentionally for aquaculture, or accidentally in shipsÆ ballast water or encrusted on their hulls. Population eruptions of certain native species ù for example, the crown-of-thorns starfish ù can also cause problems.
A number of measures have been, or are being, developed in response to these problems, most recently an Australian Ballast Water Management Strategy. A national Centre for Research on Introduced Marine Pests has also been established within CSIROÆs Marine Laboratories in Hobart to research early warning tools, better prediction, improved control methods, and more effective assessment of risks and costs.
\BFishing\b
Fishing, both commercial and recreational, imposes heavy pressure on marine species and their habitats. Most major Australian seafood species are now fully exploited. Some, such as the southern bluefin tuna and eastern gemfish, have been over-exploited. With the exception of turtles and possibly dugongs, which remain at risk, reptiles (the saltwater crocodile) and mammals (whales and seals) that have been over-hunted in the past are now recovering.
All States and the Commonwealth are revising fisheries legislation to ensure it is directed towards the principles of ecologically sustainable development. Fisheries advisory committees comprising management and industry interests have been established to help develop management plans for individual fisheries.
\BMining\b
Coastal and offshore mining activities can have an impact on marine and estuarine environments. Enterprises include sand and gravel mining, oil and gas exploration and production, coral (limestone) mining, and diamond dredging. Over the past 30 years, oil companies have drilled more than 1100 wells offshore and extracted 2800 million barrels of oil. Their environmental record has been very good, with only about 800 barrels of oil being spilt over this period.
\BSpecific environments\b
Human activities have caused extensive localised losses of saltmarshes, mangroves and seagrass beds, particularly near major population centres. Australia has the third largest area of mangroves in the world, and the northern mangroves are among the worldÆs most diverse. Our waters also have the greatest diversity of seagrasses, and some of the largest seagrass beds in the world.
Australia also has the largest area of coral reefs. By international standards, our reefs are still in good condition. However, they are now exposed to significant pressures, with those close to population centres showing the most signs of damage.
Marine protected areas are important for conserving specific environments. Although Australia has a very large number of these areas (more than 300 in 1992) most of those in the southern and eastern half of the continent are small and many environments or bioregions are not adequately represented. The Commonwealth is addressing this issue in cooperation with State and Territory governments by developing a national representative system of marine protected areas under the Ocean Rescue 2000 program.
\BSeafood quality\b
Environmental conditions affect seafood quality, with the main issue being the accumulation of contaminants in the flesh of seafood species. Our seafood is generally low in contaminants, but exceptions occur in species that accumulate heavy metals, biotoxins, microbes and chemical pollutants. Some survey information is not available for public scrutiny.
\BManagement\b
An increasing awareness of the pressures on our estuaries and seas has resulted in a range of legislative and management responses to prevent, contain and reduce degradation. For example, licensing point sources of pollution, establishing marine protected areas, oil spill contingency planning, regulation of national and international navigation to reduce maritime accident hazards and developing fisheries management plans, can all be effective in reducing or managing pressures on the environment.
However, the management of our marine and coastal systems still lacks an integrated and coordinated framework that is built on a set of ecosystem-based goals and environmental performance indicators. Apart from the Great Barrier Reef Marine Park Authority, no agency is responsible for managing the marine environment on such a basis. We do not have the long-term research and monitoring to provide baseline information at a national level, and research and management are yet to be fully integrated as the basis for sustainable use of coastal and marine resources. Such programs as the CommonwealthÆs State of the Marine Environment Report, National Marine Information System, Coastal Atlas and the Commonwealth Coastal Policy are improving the knowledge base.
\BDescription:\b Crown-of-thorns starfish can cause problems in the oceans \I(GBRMPA)\i.
#
"Coastal Management",16,jervis2.jpg,c,0
Marine management in Australia involves a large number of different management strategies and agreements, arrangements and agencies ù international, regional, Commonwealth, State and local government.
Government responsibilities in the coastal zone are fragmented and often overlap, impeding effective management and planning. One Commonwealth document lists 73 Commonwealth programs, 14 strategies, 49 pieces of Commonwealth legislation and 25 treaties that pertain to coastal zone management.
A review of government interests in Jervis Bay, New South Wales, showed that at least 22 acts of Federal Parliament and 29 acts of State Parliament apply directly to the management of the bayÆs resources.
Almost 60 government reports and inquiries have examined AustraliaÆs coastal zone since 1960. The most substantial, the 1993 report of the Resource Assessment Commission, identified the need for an integrated national approach, involving local, State and Commonwealth governments, to address the problems of the coastal zone.
The CommissionÆs inquiry found:
ò No single sphere of government can manage the zone
ò Issues of national significance and great public concern are involved
ò The socio-economic development of the coastal zone is of profound importance to the nation
ò Australia has international obligations in the zone that necessitate coordination between the spheres of government The CommissionÆs main recommendation was that Australian governments should adopt a national coastal action program to manage the resources of the coastal zone. The three spheres of government should implement the program, in consultation with community and industry groups with responsibility for and interest in coastal zone management. The Commission also proposed the enactment of a Commonwealth Coastal Resources Management Act.
In response to the CommissionÆs report, the Commonwealth announced in 1995 a coastal policy that includes funding for the coastal action program, and focuses on:
ò increasing support for community and local government participation in coastal management
ò increasing the capacity and knowledge of coastal managers
ò developing integrated solutions to problems such as urban sprawl and coastal pollution
ò conserving ecosystems, cultural and indigenous heritage sites and important landscapes
\BDescription:\b Jervis Bay \I(Readers Digest)\i
#
"Environmental Status of the Great Barrier Reef",17,02850088.jpg,c,0
The Great Barrier Reef is the largest system of coral reefs in the world. It extends over 2500 kilometres and comprises 2900 separate reefs and 940 islands. Its high species diversity includes more than 400 corals, 4000 molluscs, 1500 fish, six turtles, 35 seabirds and 23 sea mammals.
The Reef is one of AustraliaÆs best tourist attractions. About two million people visit it and the adjacent coast annually; the number is increasing by 10 per cent a year. The combined value of tourism and fishing on the Reef is estimated at about $1 billion a year.
\BPressures\b
The main pressures on the Reef include: declining water quality in inshore areas due mainly to increased sediments and nutrients; fishing; coral mortality caused by outbreaks of crown-of-thorns starfish; tourism; ballast water from shipping and the threat of oil and chemical spills.
\BState\b
The Great Barrier Reef is one of the least-disturbed coral reef systems in the world, and much of it is still in relatively good condition. There is evidence of damage and degradation in some areas, especially some of the inshore reefs. Over the past 30 years, the crown-of-thorns starfish has affected about 17 per cent of reefs, with damage ranging from slight to very severe. The causes of the outbreaks are still unknown.
\BResponse\b
The Great Barrier Reef was inscribed on the World Heritage List in 1981 and is protected under the Great Barrier Reef Marine Park Act. The park, which covers 344,000 sq kms, is the worldÆs largest protected marine area. It is managed by the Great Barrier Reef Marine Park Authority, with the Queensland Department of the Environment and Heritage responsible for day-to-day administration.
While the agency approach has worked well on a case-by-case basis, better coordination and strategic planning, involving State and local government bodies and industry, is necessary to maintain environmental protection, particularly in relation to coastal development.
The authority recently coordinated the development of a 25-year strategic plan, involving more than 70 user groups, for the Great Barrier Reef World Heritage Area. The authority intends to publish in 1996 a state of the environment report on this area. In addition, the Australian Institute of Marine Science, in conjunction with the Great Barrier Reef Marine Park Authority, has established a comprehensive long term monitoring program for the Reef.
\BDescription:\b Great Barrier Reef \I(David Ireland)\i
#
"Natural and Cultural Heritage",18,k004.jpg,c,0
AustraliaÆs natural and cultural heritage is an integral part of its environment. The state of our heritage is as important as the state of our atmosphere, land, water, seas, plants and animals. Its inclusion adds a new dimension to state of the environment reporting.
AustraliaÆs heritage comprises natural and cultural places and objects that have special significance and value to Australians because of the meanings we ascribe to them. They are imbued with human associations, stories, myths and traditions.
Heritage provides the cultural and physical links with the past. It is central to our cultural identity and a source of spiritual well-being. Natural landscapes ù with their biological and physical diversity ù and cultural landscapes ù with their diversity of cultural records and layers of meaning, objects and stories ù collectively give us our uniquely Australian æsense of placeÆ.
\BHeritage places\b
Many places remain unprotected for a number of reasons: their heritage values are not recognised; the community is not involved; social values are poorly considered in heritage studies; or resources to identify and conserve places are inadequate.
Tourism has significant effects ù both positive and negative ù on many natural and cultural places. It can lead to better management, renewed cultural activity and increased understanding, but it can also result in pollution, vandalism and cultural exploitation and debasement.
Urban development, especially in the capital cities, which have the most listed heritage places, creates pressures where, for example, places are demolished or re-used. Neglect is the main threat in areas of low or declining population.
There is no national overview of the physical condition of AustraliaÆs heritage places, and no national monitoring system. Historic places and indigenous sites of non-archaeological significance still have no legislative protection in Tasmania and such protection is weak in Western Australia and Queensland.
\BHeritage objects\b
Major pressures on heritage objects include poor national coordination, inadequate conservation facilities, loss of context (through removal from their original site, for example) and insufficient documentation. Over the past two decades, the level of technical and other support for biological collections in the major government-funded museums and herbariums has decreased significantly.
We donÆt know with any accuracy the physical condition of all objects in collections, but many are thought to be deteriorating. No national monitoring system is in place. Indigenous heritage objects in their natural locations receive legislative protection in all States.
\BIndigenous languages\b
Loss of traditional languages imposes particular pressure on the heritage of indigenous Australians because these languages provide the most appropriate way of transmitting and maintaining cultural knowledge and the traditions relating to places.
\BHeritage registers and collections\b
The size of heritage registers and collections has grown considerably over the last 20 years.
Eleven Australian sites have been inscribed on the World Heritage List, an international register of places of outstanding universal value. The Register of the National Estate (at June 1994) lists 10,772 places, of which seven per cent are Aboriginal and Torres Strait Islander, 16 per cent are natural and the remainder historic.
Although our knowledge about the state of AustraliaÆs heritage places has improved substantially (since the early 1980s), major gaps remain for some geographic and subject areas, including places of social value ù places which often seem ordinary but which are so highly valued by the community that threats of their destruction provoke strong protests.
Millions of heritage objects are located in major collecting institutions. Collections of natural objects far outnumber those of cultural items. Some types of objects are poorly represented in both natural and cultural collections. For example, museums contain relatively few objects representing the experience of migrants, working class people and women.
\BManagement\b
There have been many responses to the state of AustraliaÆs heritage and the pressures on it. Community groups, heritage professionals and some corporations and industry groups have actively supported heritage identification and conservation activities. Governments have developed specific policies and implemented major programs to help identify and conserve heritage places and objects, although some programs appear to lack adequate resources. For example, in 1994û95, the National Estate Grants Program, established to assist in identifying, conserving and presenting the National Estate, received 866 applications totalling $28 million for the $4.7 million available.
Legislative protection of heritage places has improved significantly, with governments passing ten major acts covering cultural places since 1987. Programs have been initiated for the national co-ordination of museum and other collections. All State and national museums now employ conservators, and museum policies are changing to redress imbalances in their collections.
Despite numerous positive responses to assist the identification, documentation and conservation of AustraliaÆs heritage, it is too early to assess the effectiveness of many recent initiatives. Before we can evaluate these initiatives, we need to agree nationally on which indicators are the most useful to measure the state of our heritage resources.
\BMajor issues\b
The Australian community realises it has an obligation to protect significant objects and places for future generations. We lack quantifiable national data on the physical state of our heritage, the pressures affecting it, and societyÆs response to these. Without this information, ensuring the sustainable use of our heritage resources is difficult.
The strong links between places, objects and the meanings people give to them are not reflected in current policies and institutional approaches, and no national heritage strategy exists to integrate these elements. Also, heritage considerations do not yet effectively integrate natural and cultural values. The concept of cultural landscapes ù parts of the environment that, in being significantly modified by humans, express their attitudes, values and interactions with the environment ù provides a powerful mechanism to assist this.
Australia lacks the necessary coordination between and within the three levels of government to ensure effective heritage identification and conservation and the integration of heritage values in early stages of policy and program development.
While we have made progress in many areas of indigenous heritage, indigenous communities still do not have enough say and involvement in identifying, protecting and interpreting their heritage, and in cultural tourism and language maintenance.
All groups in the Australian community need to be involved in heritage matters to ensure their heritage is acknowledged, and to assist in conserving and transmitting it to future generations in good condition.
\BDescription:\b Kakadu National Park \I(Webster Publishing)\i
#
!,!,!,!,!
2#
73,0
"Climate of Australia",1,"g\8\3_0025.jpg","f","0"
The island continent of Australia features a wide range of climatic zones, from the tropical regions of the north, through the arid expanses of the interior, to the temperate regions of the south.
Widely known as 'The Dry Continent', the land mass is relatively arid, with 80 per cent having a median rainfall less than 600 millimetres per year and 50 per cent less than 300 millimetres (the average is 450 millimetres).
Seasonal fluctuations can be large, with temperatures ranging from above 50 degrees C to well below zero. However, extreme minimum temperatures are not as low as those recorded in other continents, probably because of the absence of extensive mountain masses to induce orographic cooling (which is in the order of -0.6 degrees C/100 mm increase in elevation) and because of the large expanse of relatively warm surrounding oceans.
\BDescription:\b \JStrzelecki\j Desert \I(DFAT)\i
#
"Climatic Controls",2,1_0099.jpg,c,0
The generally low relief of Australia causes little obstruction to the atmosphere systems which control the climate. A notable exception is the eastern uplands which modify the atmospheric flow, sometimes causing the 'Easterly Dip' which is evident in some surface pressure charts.
In the winter half of the year (May-October) anticyclones, or high pressure systems, pass from west to east across the continent and may remain almost stationary over the interior for several days. These anticyclones may extend to 4,000 km wide and, in the Southern Hemisphere, rotate anticlockwise. Northern Australia is thus influenced by mild, dry south-east trade winds (the Trade Winds or 'Trades'), and southern Australia experiences cool, moist westerly winds.
The westerlies and the frontal systems associated with extensive depressions (lows, sometimes called extra-tropical cyclones) travelling over the Southern Ocean have a controlling influence on the climate of southern Australia during the winter season, causing rainy periods. Periodic north-west cloud bands in the upper levels of the atmosphere over the continent may interact with southern systems to produce rainfall episodes, particularly over eastern areas. Cold outbreaks, particularly in south-east Australia, occur when cold air of Southern Ocean origin is directed northwards by intense depressions having diameters up to 2,000 km. Cold fronts associated with the southern depressions, or with secondary depressions over the Tasman Sea, may produce strong winds and large day-to-day variations in temperature in southern areas, particularly in south-east coastal regions.
In the summer half of the year (November-April) the anticyclones travel from west to east on a more southerly track across the southern fringes of Australia directing easterly winds generally over the continent. Fine, warmer weather predominates in southern Australia with the passage of each anticyclone. Heat waves occur when there is an interruption to the eastward progression of the anticyclone (blocking) and winds back northerly and later north-westerly.
Northern Australia comes under the influence of summer disturbances associated with the southward intrusion of warm moist monsoonal air from north of the intertropical convergence zone, resulting in a hot rainy season. Southward dips of the monsoonal low pressure trough sometimes spawn tropical depressions, and may prolong rainy conditions over northern Australia for up to three weeks at a time.
Tropical cyclones are strong, well-organised low pressure systems of tropical origin where average surface winds are expected to reach at least gale force (speed equivalent of 34-40 knots). Severe tropical cyclones reach at least storm force (57-65 knots) - the highest wind speed recorded in Australia was 259 km/h, which occurred with Cyclone Trixie (February 1975).
Tropical cyclones develop over the seas where temperatures exceed 27 degrees C around northern Australia in summer, between November and April. Their frequency of occurrence and the tracks they follow vary greatly from season to season. On average, about three cyclones per season directly affect the Queensland coast, and about three affect the north and north-west coasts. Tropical cyclones approaching the coast usually produce very heavy rain and high winds in coastal areas. Some cyclones move inland, losing intensity but still producing widespread heavy rainfall and, occasionally, moderate to severe damage.
The climate of eastern and northern Australia is influenced by the Southern Oscillation (SO), a see-sawing of atmospheric pressure between the northern Australian/Indonesian region and the central Pacific Ocean. This Oscillation is one of the most important causes of climatic variation after the annual seasonal cycle over eastern and northern Australia.
The strength of the SO is determined by the Southern Oscillation Index (SOI), which is a measure of the difference in sea level atmospheric pressure between Tahiti in the central Pacific and Darwin in northern Australia. At one extreme of the Oscillation, the pressure is abnormally high at Darwin and abnormally low at Tahiti. Severe and widespread drought over eastern and northern Australia generally accompanies this extreme. These conditions generally commence early in the year, last for about 12 months and have a recurrence period of two to seven years.
The above extreme is generally immediately preceded or followed by the opposite extreme where pressures at Darwin are abnormally low and those at Tahiti are abnormally high. In this case, rainfall is generally above average over eastern and northern Australia.
The SO is linked to sea surface temperatures (SSTs) in the Pacific Ocean. Dry extreme SO years are accompanied by above normal SSTs in the central and/or eastern equatorial Pacific and vice versa. Dry extreme years are called El Ni±o years. Wet extreme years are called La Ni±a years.
\BDescription:\b A low rainfall area \I(DFAT)\i
#
"Median Annual Rainfall",3,aar.jpg,c,0
The area of lowest rainfall is in the vicinity of Lake Eyre in South Australia, where the median (50 percentile) annual rainfall is only about 100 millimetres.
Another very low rainfall area is in Western Australia in the Giles-Warburton Range region, which has a median annual rainfall of about 150 mm. A vast region, extending from the west coast near Shark Bay across the interior of Western Australia and South Australia to south-west Queensland and north-west New South Wales, has a median annual rainfall of less than 200 mm. This region is not normally exposed to moist air masses for extended periods and rainfall is irregular, averaging only one or two days per month. However, in favourable synoptic situations, which occur infrequently over extensive parts of the region, up to 400 mm of rain may fall within a few days and cause widespread flooding.
\BDescription:\b This map shows annual median rainfall \I(Australian Bureau of Meteorology, 1988, ⌐ Commonwealth of Australia. Reproduced by permission)\i
#
"Median Annual Rainfall - (2)",4,01240032.jpg,c,0
The region with the highest median annual rainfall is the east coast of Queensland between Cairns and Cardwell, where Tully has a median of 4,048 millimetres (63 years to 1987 inclusive). The mountainous region of western Tasmania also has a high annual rainfall, with Lake Margaret having a median of 3,565 millimetres (76 years to 1987 inclusive).
In the mountainous areas of north-east Victoria and some parts of the east coastal slopes there are small pockets with median annual rainfall greater than 2,500 mm.
The Snowy Mountains area in New South Wales also has a particularly high rainfall. The highest median annual rainfall for this region is 3,200 mm, and it is likely that small areas have median annual rainfall approaching 4,000 mm on the western slopes above 2,000 m elevation.
\BDescription:\b Flooding after heavy rainfall \I(Jonathan King)\i.
#
"Seasonal Rainfall",5,"g\8\seas.jpg","c","0"
The rainfall pattern of Australia is strongly seasonal in character with a winter rainfall regime in the south and summer regime in the north.
The dominance of rainfall over other climatic elements in determining the growth of specific plants in Australia has led to the development of a climatic classification based on two main parameters. The parameters are median annual rainfall and seasonal rainfall incidence.
The main features of the seasonal rainfall are:
ò marked wet summer (the 'Monsoon') and dry winter of northern Australia;
ò wet summer and relatively dry winter of south-eastern Queensland and north-eastern New South Wales;
ò uniform rainfall in south-eastern Australia - much of New South Wales, parts of eastern Victoria and southern Tasmania;
ò marked wet winter and dry summer of south-west Western Australia and, to a lesser extent, much of the remainder of southern Australia directly influenced by westerly circulation (sometimes called a 'Mediterranean' climate); and
ò arid area comprising about half the continent extending from the north-west coast of Western Australia across the interior and reaching the south coast at the head of the Great Australian Bight.
This figure shows summer maximum (orange and yellow), uniform (green) and winter maximum (light blue and dark blue) rainfall.
#
"Variability of Rainfall",6,varia.jpg,c,0
A rainday occurs where more than 0.2 mm of rain falls in 24 hours, usually from 9 a.m. to 9 a.m. the next day. The frequency of raindays exceeds 150 per year in Tasmania (with a maximum of over 200 in western Tasmania), southern Victoria, parts of the north Queensland coast and in the extreme south-west of Western Australia. Over most of the continent the frequency is less than 50 raindays per year.
The area of low rainfall with high variability, extending from the north-west coast of Western Australia through the interior of the continent, has less that 25 raindays per year.
In the high rainfall areas of northern Australia the number of raindays is about 80 days per year, but heavier falls occur in this region than in southern regions.
This figure depicts the percentage variability of annual rainfall over the continent. Rainfall variability often results in lengthy periods without rain ('dry spells') and droughts.
#
"Climatic Zones",7,aac.jpg,c,0
Australia's land use options are largely determined by climatic conditions, which in turn relate to the latitudinal position and topography of the continent. The climate has a significant effect upon the nature and quality of soils, and the amount and type of natural or cultivated vegetation that grows or can be grown.
Australia has been divided into a number of climatic zones based on rainfall patterns and mean summer and winter temperatures. This figure details these zones and their main characteristics.
Topography is less influential, since slopes are commonly gentle, and much of the landscape is relatively flat. Soils can be modified to some extent to overcome physical or chemical limitations.
\BKey to Diagram:\b
\BA\b Summer Rainfall - Tropical
\BB\b Summer Rainfall - Subtropical
\BC\b Uniform Rainfall - Temperate
\BD\b Winter Rainfall (moderate to heavy) - Temperate
\BG\b Arid (winter/non season rain) - Subtropical to warm temperate
#
"Rainfall Trends",8,3_0093.jpg,c,0
There is concern that the possibility of global warming, resulting from the greenhouse effect, may be accompanied by changes in rainfall. However, high rainfall variability from year to year makes rainfall trends difficult to discern. Even so, summer rainfall has increased over much of south-eastern Australia since the start of the century.
There has also been a decrease in winter rainfall over south-western Australia during this period. It should be noted that accurate rainfall data for north-western Australia are not available from the early 1900s.
It is tempting to attribute these rainfall trends to the greenhouse effect, however a study conducted in 1991 indicates that late twentieth century rainfalls were similar to those in the late nineteenth century. If so, the trends noted here might simply represent a return to conditions present last century, prior to any major injection of greenhouse gases.
\BDescription:\b Floods in north west NSW \I(DFAT)\i
#
"Rainfall Intensity",9,3_0099.jpg,c,0
Australia experiences periods of intense rainfall. Most of the very high falls (above 700 mm) have occurred along the Queensland coast, where heavy rains associated with tropical cyclones move inland over mountainous terrain. As a result, floods occurring in the short and often steep catchments of the coastal streams of northern New South Wales and southern Queensland have been the most severe in Australia.
Flooding of the plainlands and the distributory channel system of inland Australia is characterised by slow rising, long duration events, often the result of rainfall hundreds if not thousands of kilometres away.
Almost all riverine floods in Australia result from excess rainfall; only in streams draining the Snowy Mountains, Southern Alps and Tasmania does snow-melt contribute to flood flows.
\BDescription:\b Floods in north west NSW \I(DFAT)\i
#
"Evaporation of Rainfall",10,evap.jpg,c,0
The effectiveness of rainfall can be reduced by its unreliability, by high intensity, and by losses through evaporation and transpiration. Evaporation depends on temperature, wind, humidity and cloud cover. In Australia, where surface water storage is vital over large areas, evaporation is a highly significant element. Average annual pan evaporation is mapped in this figure.
Pan evaporation is determined by measuring the amount of water evaporated from a free water surface exposed in a pan. In areas south of the tropics, average monthly evaporation follows seasonal changes in solar radiation, giving highest evaporation in December and January, and lowest in June and July.
In the tropics, onset of summer brings increasing cloudiness and higher humidity, causing reduced evaporation in these months. Maximum evaporation in tropical areas occurs around November.
\BDescription:\b Average annual evaporation \I(ABS)\i
#
"Rainfall and Run-off",11,spread241.spr,c,0
Water resources are determined by precipitation (rain, hail, snow), evaporation and physical features including soil, vegetation and geology.
This table compares rainfall and run-off for the continents and shows that Australia not only has the lowest rainfall and run-off (proportional to area) but also the lowest percentage of run-off to rainfall incidence. In other words, the rainfall which is yielded as streamflow after evaporation and transpiration is meagre.
#
"Drainage",12,hwksbry2.jpg,c,0
In Australia, the portion of run-off available for use is very low compared with other continents. This results from the high variability of streamflow, high rates of evaporation and the lack of storage sites on many catchments.
With the exception of the Murray-Darling system, most rivers draining to the ocean are comparatively short but account for the majority of the country's average annual discharge. In some arid areas with low relief, surface drainage is totally absent.
In total there are 245 river basins which combine to form 12 main drainage divisions. The drainage division with the highest intensity of run-off is Tasmania with 13% of the total from only 0.8% of the area. Conversely, the vast area of the Western Plateau (2,450,000 square kilometres, approximately 32% of Australia) has no significant run-off at all.
To summarise, the mean annual run-off across Australia is 397 million megalitres. Thus, total divertible fresh and marginal water represents approximately 25% of mean annual run-off.
\BDescription:\b The Hawkesbury River \I(Webster Publishing)\i
#
"Thunderstorms and Hail",13,"g\8\7_0010.jpg","c","thunder0"
A thunderday at a given location is a calendar day on which thunder is heard at least once.
The average annual number of thunderdays varies from 74 per year near Darwin to less than 10 per year over parts of the southern regions. Convectional processes during the summer wet season cause high thunderstorm incidence in northern Australia.
Hail, mostly of small size (less than 10 millimetres diameter), occurs with winter-spring cold frontal activity in southern Australia. Summer thunderstorms, particularly over the uplands of eastern Australia, sometimes produce large hail (greater than 10 millimetres in diameter).
Large hail capable of piercing light-gauge galvanised iron occurs at irregular intervals and sometimes causes widespread damage.
\BDescription:\b Thunderstorm forming off the Darwin coast \I(Peter Jarver)\i
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"Snow",14,"a\2\3_0051.jpg","c","wind0"
Generally, snow covers much of the Australian Alps above 1,500 metres for varying periods from late autumn to early spring. Similarly, in Tasmania the mountains are covered fairly frequently above 1,000 metres in these seasons.
The area, depth and duration are highly variable. In some years, snow falls in the altitude range of 500-1,000 metres. Snowfalls at levels below 500 m are occasionally experienced in southern Australia, particularly in the foothill areas of Tasmania and Victoria, but falls are usually light and short lived. In some seasons, parts of the eastern uplands above 1,000 m from Victoria to south-eastern Queensland have been covered with snow for several weeks. In ravines around Mount Kosciuszko (2,228 metres) small areas of snow may persist through summer but there are no permanent snowfields.
Average annual air temperatures range from 28 degrees C along the Kimberley coast in the extreme north of Western Australia to 4 degrees C in the alpine areas of south-eastern Australia.
July is the month with the lowest average temperature in all parts of the continent. The months with the highest average annual temperature are January or February in the south and December in the north (except in the extreme north and north-west where it is November). The slightly lower temperatures of mid-summer in the north are due to the increase in cloud during the wet season.
\BDescription:\b View from Olsens Lookout, Snowy Mountains \I(DFAT)\i
#
"Average Monthly Maximum and Minimum Temperatures",16,"g\8\7_0097.jpg","c","0"
In January, average maximum temperatures exceed 35 degrees C over a vast area of the interior and exceed 40 degrees C over appreciable areas of the north-west.
The consistently hottest part of Australia in terms of summer maxima is around \JMarble Bar\j in Western Australia (150 kilometres south-east of Port Hedland) where the average is 41 degrees C and daily maxima during summer may exceed 40 degrees C consecutively for several weeks at a time.
In July, a more regular latitudinal distribution of average maxima is evident. Maxima range from 30 degrees C near the north coast to 5 degrees C in the alpine areas of the south-east.
In January, average minima range from 27 degrees C on the north-west coast to 5 degrees C in the alpine areas of the south-east. In July, average minima fall below 5 degrees C in areas south of the tropics (away from the coasts). Alpine areas record the lowest temperatures; the July average is as low as -5 degrees C.
\BDescription:\b Devils Marbles, \JAlice Springs\j where extreme temperatures can occur \I(Peter Jarver)\i
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"Extreme Maximum Temperatures",17,"spread273.spr","c","0"
Temperatures have exceeded 45 degrees C at nearly all inland stations more than 150 kilometres from the coast and at many places on the north-west and south coasts.
Temperatures have exceeded 50 degrees C at some inland stations and at a few near the coast. It is noteworthy that Eucla on the south coast has recorded 50.7 degrees C, the highest temperature in Western Australia. This is due to the long trajectory over land of hot north-west winds from the Marble Bar area.
Although the highest temperature recorded in Australia was 53.1 degrees C at Cloncurry (Queensland), more stations have exceeded 50 degrees C in western New South Wales than in other areas due to the long land trajectory of hot winds from the north-west interior of the continent.
This table lists extreme maximum temperatures for a number of areas around Australia. (You will need to use the scroll bar at the extreme right of the screen to view all entries in this table.)
The lowest temperatures in Australia have been recorded in the Snowy Mountains, where Charlotte Pass (elevation 1,760 metres) recorded -23 degrees C on 28th June 1994. Temperatures have fallen below -5 degrees C at most inland places within a few kilometres of southern coasts.
At Eyre, on the south coast of Western Australia, a minimum temperature of -4.3 degrees C has been recorded, and at Swansea, on the east coast of Tasmania, the temperature has fallen as low as -5 degrees C.
In the tropics, extreme minima below 0 degrees C have been recorded at many places away from the coasts - as far north as Herberton, Queensland (-5 degrees C). Even very close to the tropical coastline, temperatures have fallen to 0 degrees C, a low recording being -0.8 degrees C for Mackay.
This table lists minimum temperatures for a number of areas around Australia. (You will need to use the scroll bar at the extreme right of the screen to view all entries in this table.)
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"Heat Waves",19,"g\8\4_0024.jpg","c","0"
Periods with a number of successive days having a temperature higher than 40 degrees C are relatively common in summer over parts of Australia. With the exception of the north-west coast of Western Australia, however, most coastal areas rarely experience more than three successive days of such conditions.
The central part of the Northern Territory and the \JMarble Bar\j-Nullagine area of Western Australia have recorded the most prolonged heat waves. \JMarble Bar\j is the only station in the world where temperatures of more than 37.8 degrees C (100 degrees F) have been recorded on as many as 161 consecutive days (30 October 1923 to 7 April 1924).
Heat waves are experienced in the coastal areas from time to time. During 11-14 January 1939, for example, a severe heat wave affected south-eastern Australia: Adelaide had a record 47.6 degrees C on the 12th, Melbourne a record 45.6 degrees C on the 13th, and Sydney a record 45.3 degrees C on the 14th.
The Kimberley district of Western Australia is consistently the hottest part of Australia in terms of annual average maximum temperatures. Wyndham, for example, has an annual average maximum of 35.6 degrees C.
\BDescription:\b Australia's beautiful beaches are a welcome haven for people from the summer heatwaves \I(DFAT)\i
The table on this page gives statistical weather averages for 12 cities and towns around Australia. These readings were taken in January, representing the middle of Summer.
The table on this page gives statistical weather averages for 12 cities and towns around Australia. These readings were taken in April representing the middle of Autumn.
The table on this page gives statistical weather averages for 12 cities and towns around Australia. These readings were taken in July, representing the middle of Winter.
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"Average Spring Weather",23,"spread414.spr","c","0"
The table on this page gives statistical weather averages for 12 cities and towns around Australia. These readings were taken in October, representing the middle of Spring.
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"Hottest Capital City Day",24,"spread415.spr","c","0"
This table lists the hottest recorded day in degrees Celsuis for each capital city.
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"Coldest Capital City Night",25,"spread416.spr","c","0"
This table lists the coldest recorded night in degrees Celsuis for each capital city.
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"Wettest Capital City Month",26,"spread417.spr","c","0"
This table lists the wettest recorded month for each capital city.
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"Wettest Capital City Day",27,"spread418.spr","c","0"
This table lists the wettest recorded day for each capital city.
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"Average Temperatures and Sunshine",28,"spread419.spr","c","0"
This table lists the average of three major weather components for all capital cities.
The first column of data (Summer Average) lists the average January daily maximum temperature in degrees Celsius.
The second column of data (Winter Average) lists the average July daily minimum temperature in degrees Celsius.
The third column of data (Sunshine Average) lists the average hours per day of sunshine.
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"Average Rainfall and Wind",29,"spread420.spr","c","0"
This table lists the average of three major weather components for all capital cities.
The first column of data (Rainfall Average) lists the annual rainfall in millimetres.
The second column of data (Rain Days Average) lists the average days of rain per year.
The third column of data (Wind Average) lists the average wind speed in km/h.
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"Frost",30,"spread275.spr","f","0"
Frost frequency depends on location and orography, and even on minor variations in topography.
Frost hazard will be greatest in areas which are away from the immediate coast, are at relatively high elevations and have complex terrain which is conducive to cold air drainage. The parts of Australia which are most subject to frost are the eastern uplands from north-eastern Victoria to the western Darling Downs in southern Queensland.
Most stations in this region experience more than ten nights a month with readings of 0 degrees C (or under) for three to five months of the year. On Tasmania's Central Plateau similar conditions occur for three to six months of the year. Frosts may occur within a few miles off the coasts except in the Northern Territory and most of the north Queensland coasts.
Regions in which frosts may occur at any time of the year comprise most of Tasmania, large areas of the tablelands of New South Wales, much of inland Victoria, particularly the north-east, and a small part of the extreme south-west of Western Australia.
Over most of the interior of the continent, and on the highlands of Queensland as far north as the Atherton Plateau, frosts commence in April and end in September. Minimum temperatures below 0 degrees C are experienced in most of the subtropical interior in June and July.
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"Median Frost Period",31,"g\8\3_0036.jpg","c","0"
The median frost period over the continent varies from over 200 days per year in the south-eastern uplands south of the Hunter Valley, to zero days in northern Australia. In the southern regions of the continent, the annual frost period generally decreases from about 100 days inland to below 50 days towards the coast.
However, there are appreciable spatial variations depending mainly on local orography. In Tasmania the frost period exceeds 300 days on the uplands and decreases to 100 days near the coast.
The regions of mainland Australia most prone to heavy frosts are the eastern uplands and adjacent areas extending from Victoria through New South Wales to south-eastern Queensland. Stations above 1,000 m in altitude in the southern parts of these uplands have more than 100 heavy frosts annually, and in the upland areas below 1,000 m the annual frequency ranges from 100 to about 20. Over the remainder of southern Queensland, New South Wales and Victoria, although there are great spatial variations, the average annual frequency of heavy frosts typically ranges from about 20 inland to 10 towards the coast.
In Tasmania, uplands above 1,000 m have more than 100 heavy frosts annually and, in neighbouring areas, the frequency is about 100 decreasing to 20 towards the coasts. Even some coastal stations have a relatively high frequency (Swansea, for example, has 16).
The southern half of Western Australia, the whole of South Australia, and the Alice Springs district of the Northern Territory experience heavy frosts. Differences in annual frequencies between places are great, but in general the frequency is about 10 inland decreasing towards the coasts. Some places average more than 20 heavy frosts annually, notably Wandering, Western Australia (22) and Yongala, South Australia (42). At Alice Springs the annual average frequency is 12.
\BDescription:\b Mt. Nelson, Hobart has a large number of frost days per year \I(DFAT)\i
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"Humidity",32,"g\8\1_0100.jpg","c","sail10"
Australia is a dry continent in terms of the water vapour content or humidity of the air, and this element may be compared with evaporation to which it is related. Moisture content can be expressed by a number of parameters, of which the most commonly known is relative humidity. Relative humidity can be thought of as the relative evaporating power of the air; when the humidity is low, a wet surface, like our skin, can evaporate freely. When it is high, evaporation is retarded. People can feel this as discomfort or even stress as the body's ability to perspire (and hence cool) decreases with increasing relative humidity.
The main features of the relative humidity pattern are:
* over the interior of the continent there is a marked dryness during most of the year, notably towards the northern coast in the dry season (May-October);
* the coastal fringes are comparatively moist, although this is less evident along the north-west coast of Western Australia where continental effects are marked;
* in northern Australia, the highest values occur during the summer wet season (December- February) and the lowest during the winter dry season (June-August); and
* in most of southern Australia the highest values are experienced in the winter rainy season (June-August) and the lowest in summer (December-February).
\BDescription:\b Along Australia's coastal fringes the air is comparatively moist \I(DFAT)\i
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"Global Radiation",33,"0","g","0"
Global (short wave) radiation includes that radiation energy reaching the ground directly from the sun and that received indirectly from the sky, scattered downwards by clouds, dust particles, etc.
A high correlation exists between daily global radiation and daily hours of sunshine. On the north-west coast around Port Hedland, where average daily global radiation is the highest for Australia (640 milliwatt hours), average daily sunshine is also highest, being approximately 10 hours. Sunshine is more dependent on variations in cloud coverage than is global radiation, since the latter includes diffuse radiation from the sky as well as direct radiation from the sun. An example is Darwin where, in the dry month of July, sunshine approaches twice that of the wet (cloudy) month of January, but global radiation amounts for the two months are comparable.
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"Sunshine",34,"g\8\01240020.jpg","c","0"
Sunshine as treated here refers to bright or direct sunshine. Australia receives relatively large amounts of sunshine although seasonal cloud formations have a notable effect on its spatial and temporal distribution. Cloud cover reduces both incoming and outgoing long wave radiation and thus affects sunshine, air temperature and other climatic elements on the Earth's surface.
Most of the continent receives more than 3,000 hours of sunshine a year, or nearly 70% of the total possible. In central Australia and the mid-west coast of Western Australia, totals slightly in excess of 3,500 hours occur. Totals of less than 1,750 hours occur on the west coast and highlands of Tasmania; this amount is only 40% of the total possible per year (about 4,380 hours).
In southern Australia the duration of sunshine is greatest about December when the sun is at its highest elevation, and lowest in June when the sun is lowest. In northern Australia sunshine is generally greatest about August-October prior to the wet season, and least about January-March during the wet season.
\BDescription:\b Sunshine after heavy rainfalls in the Northern Territory \I(Johnathan King)\i.
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"Cloud",35,"g\8\7_0059.jpg","f","0"
Seasonal changes in cloudiness vary with the distribution of rainfall. In the southern parts of the continent, particularly in the coastal and low lying areas, the winter months are generally more cloudy than the summer months. This is due to the formation of extensive areas of stratiform cloud and fog during the colder months, when the structure of the lower layers of the atmosphere favours the physical processes resulting in this type of cloud.
Particularly strong seasonal variability of cloud cover exists in northern Australia where skies are clouded during the summer wet season and mainly cloudless during the winter dry season. Cloud coverage is greater near coasts and on the windward slopes of the eastern uplands of Australia and less over the dry interior.
\BDescription:\b An example of a mildly cloudy day \I(Peter Jarver)\i
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"Fog",36,"g\8\3_0045.jpg","f","0"
The formation of fog depends on the occurrence of favourable meteorological elements - mainly temperature, humidity, wind, and cloud cover. The nature of the local terrain is important for the development of fog and there is a tendency for this phenomenon to persist in valleys and hollows. The incidence of fog may vary significantly over distances as short as one kilometre.
Fog in Australia tends to be more common in the south than in the north, although parts of the east coastal areas are relatively fog-prone even in the tropics. Incidence is much greater in the colder months, particularly in the eastern uplands. Fog may persist during the day but rarely until the afternoon over the interior.
The highest fog incidence at a capital city is at \JCanberra\j which has an average of 47 days per year on which fog occurs, 29 of which are in the period of May to August. Brisbane averages 20 days of fog per year. Darwin averages only 2 days per year, in the months of July and August.
\BDescription:\b Fog in the hills around \JCanberra\j \I(DFAT)\i
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"Winds",37,"a\9\mel8.jpg","c","wind0"
The mid-latitude anticyclones are the chief determinants of Australia's two main prevailing wind streams. In relation to the west-east axes of the anticyclones, these streams are easterly to the north and westerly to the south. The cycles of development, motion and decay of low-pressure systems to the north and south of the anticyclones result in diversity of wind-flow patterns. Wind variations are greatest around the coasts where diurnal land and sea-breeze effects are important.
Orography affects the prevailing wind pattern in various ways, such as the channelling of winds through valleys, deflection by mountains and cold air drainage from highland areas. An example of this channelling is the high frequency of north-west winds at Hobart caused by the north-west to south-east orientation of the Derwent River Valley.
Perth is the windiest capital with an average wind speed of 15.6 kilometres per hour; \JCanberra\j is the least windy with an average speed of 5.4 kilometres per hour.
The highest wind speeds and gusts recorded in Australia have been associated with tropical cyclones. The highest recorded gust was 259 kilometres per hour at Mardie (near Onslow), Western Australia, on 19 February 1975, and gusts reaching 200 kilometres per hour have been recorded on several occasions in northern Australia with cyclone visitations.
The highest gusts recorded at Australian capitals were 217 kilometres per hour at Darwin and 156 kilometres per hour at Perth.
\BDescription:\b Perth is the windiest capital \I(Webster Publishing)\i
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"Droughts",38,"f\3\1_0090.jpg","c","0"
Drought, in general terms, refers to an acute deficit of water supply to meet a specified demand. The best single measure of water availability in Australia is rainfall, although parameters such as evaporation and soil moisture are significant, or even dominant in some situations. Demands for water are very diverse, hence the actual declaration of drought conditions for an area will generally also depend on the effects of a naturally occurring water deficit on the principal local industries.
Since the 1860s there have been 10 major Australian droughts. Some of these major droughts could be described as periods consisting of a series of dry spells of various lengths, overlapping in time and space, and totalling up to a decade.
The drought periods of 1895-1903, 1958-1968, 1982-83 and 1991-95 were the most devastating in terms of their extent and effects on primary production. The latter drought resulted in a possible $5 billion cost to Australia's economy, and $590 million in drought relief by the Commonwealth Government. The remaining major droughts occurred in 1864-66 (and 1868), 1880-86, 1888, 1911-16, 1918-20 and 1939-45.
In this same period, droughts of a lesser severity caused significant losses over large areas of some States. They occurred in 1922-23, 1926-29, 1933-38, 1946-49, 1951-52, 1970-73 and 1976.
South-eastern Australia (New South Wales, southern Queensland, Victoria, Tasmania and the settled parts of South Australia) contains about 75% of the nation's population, and droughts affecting this region have a markedly adverse impact on the economy. There have been eight severe droughts in south-eastern Australia since 1888.
\BDescription:\b Country towns in outback Australia suffer greatly from droughts \I(DFAT)\i
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"Climate and Floods",39,"g\8\3_0099.jpg","c","0"
Widespread flood rainfall may occur anywhere in Australia, but it has a higher incidence in the north and in the eastern coastal areas. It is most economically damaging along the shorter streams flowing from the eastern uplands to the seaboard of Queensland and New South Wales.
These flood rains are notably destructive in the more densely populated coastal river valleys of New South Wales - the Tweed, Richmond, Clarence, Macleay, Hunter and Nepean-Hawkesbury - all of which experience relatively frequent flooding. Although chiefly caused by summer rains, they may occur in any season.
The great Fitzroy and Burdekin river basins in Queensland receive flood rains during the summer wet seasons. Much of the run-off due to heavy rain in north Queensland west of the eastern uplands flows southward through the normally dry channels of the network of rivers draining the interior lowlands into Lake Eyre.
This widespread rain may cause floods over an extensive area, but it soon seeps away or evaporates, occasionally reaching the lake in quantity. The Condamine and other northern tributaries of the Darling also carry large volumes of water from flood rains south through western New South Wales to the Murray, and flooding occurs along their courses at times.
Flood rains occur at irregular intervals in the Murray-Murrumbidgee system of New South Wales and Victoria, the coastal streams of southern Victoria, and the north coast streams of Tasmania.
\BDescription:\b Floods occurring in NSW \I(DFAT)\i
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"Reading and Understanding the Weather Map",40,"0","g","0"
The weather map is one of the most familiar images in the community. The best known map is the mean sea level analysis, compiled from hundreds of weather observations (synoptic data) taken simultaneously around the Australian region. It is seen daily on television and in the newspapers.
Its dominant features are the smooth, curving patterns of sea level isobars - lines of equal atmospheric pressure - which show the central elements of our weather systems: highs, lows (including tropical cyclones) and cold fronts. It incorporates the effects of atmospheric processes at higher levels.
Television and newspapers also often carry forecast weather maps which indicate how the weather patterns are expected to develop.
Meteorologists use a wide range of information and techniques to formulate weather forecasts. The weather map does not and cannot show all of these factors. It is a fairly simple representation of past and probable future locations of surface weather systems (highs, lows, fronts, etc.). Nevertheless it provides a useful guide to the weather.
Everyone benefits from a better understanding of the weather map, especially people whose activities are particularly weather-sensitive - pilots, farmers, mariners, builders, outdoor sports enthusiasts - who often find the maps valuable, sometimes essential, to enhance their understanding of forecasts and help form their own ideas based on local experience.
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"What the Symbols on Weather Maps Represent",41,"0","g","0"
The most obvious feature of the media's weather maps are the patterns of high and low pressure, and the barbed lines identifying cold fronts. In the southern hemisphere, the earth's rotation causes air to flow clockwise around low pressure systems and anticlockwise around high pressure systems. (The opposite applies in the northern hemisphere.)
Friction on the earth's surface causes the winds to be deflected slightly inwards towards low pressure centres, and slightly outwards from high pressure systems. Wind strength is directly proportional to the distance between isobars - the closer the lines, the stronger the winds.
This rule does not apply in the tropics where the effect of the earth's rotation is weak. For this reason, tropical meteorologists usually replace isobars with streamline arrows which indicate wind and direction without directly relating to the pressure gradient.
Shaded areas on weather maps show where there has been rain in the previous 24 hours, and wind direction is shown with arrows that have a series of barbs on their tails to indicate speed.
The coverage on media weather charts is usually limited to the continent and surrounding oceans. The Bureau also produces global charts to take account of weather systems interacting with each other rapidly over great distances. Global charts are necessary when preparing forecasts up to four days ahead, and framing the monthly climate monitoring bulletins.
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"Climate and Agriculture",42,moist.jpg,c,0
This map shows climate and possible activities. A key to the letters on the map follows:
\BSH = Summer high
SA = Summer adequate
WH = Winter high
WA = Winter adequate
WL = Winter low\b
Plant growth is influenced by the combined effects of light, temperature and moisture.
Being a sunny, mid to low latitude continent, light is rarely a limiting factor. However, high rates of evaporation and poor effective rainfall results from Australia's generally warm and dry climate combined with soils that do not retain water well.
The ability and extent to which rainfall can be absorbed, held in the soil and be available for plant use has particular impact on the use of the land for agricultural purposes.
Despite comparatively low rainfall, at least some rain is trapped by the soil before it evaporates, even in the driest areas where evaporation exceeds rainfall. As a result there are no large vegetationless areas like those that occur in the Sahara and Arabian deserts.
All these factors affect the area of land utilised for specific purposes such as agriculture, human settlement and forestry. Moisture, temperature and the growing season reflect the relationship between the areas of effective rainfall and the area of land that is available for various agricultural activities, as shown in this figure. Summer high and summer adequate are related to temperate conditions and winter high, winter low and winter adequate are related to moisture conditions.
In central Australia, where there is little effective rainfall and an arid/subtropical climatic zone, growth periods are restricted to less than three months. In contrast, regions in south-western and eastern Australia on average have much greater effective rainfall and growing seasons which exceed five months.
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"History of Land Use",43,"f\3\2_0059.jpg","c","tractor0"
The history of land use in Australia falls into three broad phases. The first refers to the tens of thousands of years during which Aboriginal inhabitants pursued a largely hunter/gatherer mode of existence.
A second phase began with the arrival of Europeans in 1788 and was marked by rapid occupation and clearing of land, pioneering of agriculture and the introduction of exotic animals and plants.
The third phase dates from about the beginning of the present century and is characterised by much more intensive agriculture and concentrated urbanisation.
\BDescription:\b Rice agriculture \I(DFAT)\i
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"El Nino-Southern Oscillation",44,"f\5\2_0080.jpg","c","0"
Australian soils are considered ancient and extremely fragile. A mere 10% of Australia's huge expanse is actually arable.
Rainfall variability, particularly the differences between years which can affect drought frequency, is evident in most of the country, even in the humid coastal areas. In particular, severe droughts are frequently heralded by a huge instability of atmosphere and ocean known as the El Nino-Southern Oscillation.
El Nino is an area of abnormally warm water that occasionally appears off Peru in late December, possibly as a result of submarine volcanic activity. This warming and subsequent cooling down are associated with a reversal every three to eight years in relative atmospheric pressure and wind directions between the western and eastern Pacific - called the Southern Oscillation.
During this event the normally warm waters of the western Pacific and their associated rain-bearing clouds move east, away from Australia.
Even given these factors, and the differing patterns of rainfall, for example, monsoonal (summer) and Mediterranean (winter), Australia is home to many rural industries and agricultural production of great importance.
\BDescription:\b Sugarcane fields \I(DFAT)\i
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"Land Use in Australia",45,"spread236.spr","c","0"
Land in Australia supports a vast range of land uses including: agricultural production, forestry and logging, mining and quarrying, human settlements, transport and communication, nature conservation and recreation.
Nearly $20,000 million or 40% of gross export earnings come from soil based activities within Australia.
This table gives an approximate breakdown of land use in Australia, a notable feature of which is the large proportion of the country used in agricultural production.
In just over 200 years of European settlement, Australia has developed extensive networks of agricultural production and is ranked among the world's leading producers and exporters of foodstuffs, natural fibres and livestock.
Australia's wide range of soil types and climatic zones allows numerous crops and pastures to be grown across the country. Some of the main farming industries include beef and dairy cattle, sheep, cereal grains, sugarcane, oilseeds, cotton, and intensive cropping such as grapes, orchard fruit, tropical fruit, vegetables, tobacco and nurseries.
This map shows the distribution of these types of activities.
\BKey to Map:
1 - Sheep (with beef cattle in many areas
2 - Beef cattle
3 - Wheat and other dryland cereals
4 - Dairy cattle
5 - Sugar cane\b
The map shows that most agricultural activity in Tasmania is around the north-east of the State. On the mainland, agriculture is widespread, with huge beef cattle areas. It is basically only western-central Australia and some land reserves which are not utilised for farming to some degree.
Farms in Australia cover approximately 463 million hectares, or about 60 per cent of the land surface, and support numerous different types of farming.
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"Production of Mineral Resource Products",47,"f\4\1_0049.jpg","c","0"
The Australian mineral industry provides construction materials, fuel and industrial raw materials. It now produces some 65 different mineral commodities.
Australia is one of the world's leading miners of bauxite (the ore of aluminium), diamonds, gold, iron ore, lead, manganese ore, nickel, titanium (rutile and ilmenite), tungsten, zinc and zircon. It mines, or has unworked deposits of, almost all mineral commodities. Of the major mineral raw materials, Australia now lacks only sulphur.
The mining industry in Australia has contributed to decentralisation of population and industry, with towns, railways and ports established to serve the mines and smelters. Such ventures impact upon the natural environment as they develop and extend across Australia.
While the total area of land utilised in mining and extraction processes as such is minute in comparison with most other forms of land use, the immediate impacts are generally considerable.
Strip mining involves the extraction of ores via removal and processing of expanses of the land surface, interfering with natural habitats, causing problems in controlling water-borne pollution and making surrounding areas susceptible to erosion. Acid wastes may be released from abandoned shaft mines.
\BDescription:\b Mining bauxite in the Northern Territory \I(DFAT)\i
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"Classification of Land Degradation",48,"g\8\2_0055.jpg","c","0"
The Australian landscape is characterised by shallow and low fertility soils with hard setting character and strong texture contrast, under a highly variable, seasonal rainfall. The low soil nutrient levels are due to low organic input and leaching which has removed minerals required for plant growth.
Soil formation under present day Australian conditions is a very slow process, estimated at less than one tonne per hectare per year. In many areas it is too low to measure. Therefore the soil resources that exist now are regarded as virtually non-renewable.
The effect of European settlement in Australia has been to accelerate the rate of natural erosion processes, resulting in significant land degradation.
Land degradation may result from overgrazing, excessive tillage, vegetation clearance, urbanisation, waste disposal, introduction of pest species and climatic fluctuations.
\BDescription:\b Land degradation can result from vegetation clearance \I(DFAT)\i.
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"Water Erosion",49,"g\8\eros.jpg","c","0"
Water erosion is the most widespread form of land degradation in Australia. The process involves soil removal by rainfall or running water. Problems associated with this form of land degradation include: deterioration of drainage lines, siltation of dams, damage to roads and railways, and severe flooding.
Water erosion along river and stream banks is a minor form of erosion, at least in terms of overall economic impact. Slowest rates of denudation occur when precipitation is high, allowing good vegetation growth and hence stability and protection.
The fastest rates of stream denudation occur in situations where effective rainfall is not great enough to enable good vegetative cover, particularly where land is tilled or heavily grazed, yet high enough at intervals to provide excess runoff.
This figure shows areas susceptible to water erosion.
\BKey to Diagram:\b
\B1:\b \ICropping areas subject to regular severe damage if left bare\i
\B2:\b \ICropping areas subject to frequent severe damage if left bare\i
\B3:\b \ICropping areas subject to infrequent moderate damage if left bare\i
\B4:\b \ICropping areas subject to minor infrequent or localised damage\i
\B5:\b \INil or no damage\i
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"Wind Erosion",50,"g\9\winderos.jpg","c","0"
Wind erosion is the process where soil particles are detached from the soil surface and blown away by wind. It affects land to a much lesser extent than does water erosion.
Australian agricultural regions most adversely affected by wind erosion are inland areas used for dryland farming purposes, where soil types are mainly sandy and rainfall is less than 375 mm per annum.
Severity of wind erosion varies according to location, climate, management practices and physical soil factors. Interestingly, 34% of land susceptible to wind erosion is used for grazing and 94% of susceptible land is used for cropping.
Production losses resulting from wind erosion are estimated to be approximately $3.6 million per year. However, this is only 0.5% of the total cost of all forms of land degradation.
This figure shows areas susceptible to wind erosion.
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"Soil Acidification",51,"g\9\area533.jpg","c","0"
Soil acidification occurs as soils become increasingly acid (pH value below 7.0) to the point where plant growth and yields decline. This generally happens in areas used for grazing and cropping where rainfall is more than 500 mm annually and where acidic nitrogen fertilisers or sub-clover pastures have been grown on solodic soils or sands.
Present estimates of costs of soil affected by acidification are over $134 million a year in production loss. This is approximately 17% of total land degradation costs, second only to losses resulting from soil structure decline (about 75%).
This map shows areas of induced soil acidity.
#
"Salinity",52,"g\9\soilsal.jpg","c","0"
Salinisation is widespread in Australia. It is the process where salt accumulates in soil or water to such an extent that it affects the use of the soil for plant growth and/or water for supply to humans, stock or industry. There are two main forms of salinity:
ò Primary salinity - areas where high salinity levels occur naturally, e.g. salt marshes, salt flats, salt lakes.
ò Secondary salinity - affected areas have increased salt levels generally resulting from two major human activities: the removal of trees, and irrigation.
The removal of trees reduces transpiration and allows rainfall intake to go beyond the root zone. This can result in water tables being raised, frequently bringing salty water close to the surface. The salt becomes concentrated by evaporation, often to the point where vegetation is damaged or destroyed.
Irrigation can cause salinity due to the repeated use of saline river water. If more water is applied than is needed, surplus water passes through the soil collecting more salts, before returning to the river by natural drainage. The effect can be multiplied as water is reused for further irrigation downstream. If less water than required is applied, retained salts build up with repeated applications until adverse effects occur.
Irrigation salinity is also caused by the over-irrigation of alluvial valley soil of low permeability, resulting in a damming effect which raises local saline water tables.
Major areas of non-irrigated saline soils in Australia occur in the southern parts of the continent. In most cases saline soils develop in valleys of prime agricultural land.
This figure illustrates the areas of secondary salinity.
Soil structure decline is an undesirable change or breakdown in soil structure (the arrangement of soil particles to form aggregates or clods). This form of degradation is widespread, second only to water erosion. It is generally caused by land management practices, e.g. excessive cultivation, stubble burning.
Soil structure decline varies in severity and type with different physical properties of soils and different farm management. Generally it results in: sowing delays, poor germination and seedling emergence, waterlogging, retarded root growth, increased susceptibility to disease, poor infiltration and accentuated run-off. In a number of situations the effects of soil structure decline can be addressed and even reversed.
This figure shows areas of soil structure decline.
The loss of vegetation cover through excessive clearing of native vegetation is now generally accepted as directly contributing to land degradation problems. These problems include dryland salinity, weed invasion, soil erosion and soil structural decline.
Human induced processes which can lead to degradation include the introduction of noxious weeds, the replacement of palatable grass and herbaceous species with less desirable species as a result of overgrazing, particularly in arid and semi-arid rangeland, and the spread of woody shrubs.
The overuse of chemical fertilisers and herbicides can favour resistant weed species and remove drought-tolerant natives.
Woody shrub invasion is occurring in the arid regions of New South Wales and southern Queensland in particular. Inedible native plants are rapidly infesting large areas that previously supported pasture grasses and a sheep grazing industry.
Growing up to three metres high, woody shrubs occur as individual plants, in clumps, or more commonly as dense stands. The spread is apparently the result of reduced incidence of fire and other environmental factors.
In this figure you can see the extent of woody shrub encroachment.
In recent years land degradation has come to be recognised as one of the most important environmental issues facing Australia. A number of responses have been developed including community based activities. While community action is vital to effectively address environmental problems, governments have acknowledged that they also have very important roles to play.
Since 1983 the Commonwealth Government has taken an active role in dealing with land degradation issues, principally through the National Soil Conservation Program (NSCP).
In 1989, through the Australian Soil Conservation Ministerial Council, the States, Territories and the Commonwealth Governments released a National Soil Conservation Strategy. This provides a broad framework for land management policy development and is based on the National Conservation Strategy for Australia adopted by the Commonwealth in 1983.
The Commonwealth also supports research into a wide range of subjects. In many cases this has been undertaken in a cooperative fashion between agencies such as the Commonwealth Scientific and Industrial Research Organisation \J(CSIRO)\j and academic institutions.
#
"Decade of Landcare Plan",55,"g\9\vegaus.jpg","c","0"
Commonwealth, State and Territory Ministers responsible for soil conservation agreed in 1990 to develop a National Decade of Landcare Plan. The Plan, which was launched in January 1992, integrates action by governments, individuals and the community to address land degradation in Australia until the year 2000. The National Plan is made up of separate Commonwealth, State and Territory components plus a National Overview.
The Plan provides a strategic framework for an ongoing process which looks to the future and works towards achieving ecologically sustainable land use through the management of land degradation.
\BDescription:\b Changes in vegetation since 1788 \I(ABS, AUSLIG, 1992, ⌐ Commonwealth of Australia, reproduced by permission)\i
#
"Wetlands",56,"a\3\murray2.jpg","c","water30"
Typically, wetlands consist of swamp, shallow water or waterlogged land over which the water covering may be cyclical or permanent.
Wetlands provide food and cover for wildlife, fish and birds and also serve as breeding habitats. In addition to their biological and ecological significance, wetlands also perform important roles in flood control, groundwater recharge, erosion control and water purification.
Even though there are no reliable figures as to how many wetlands exist or the extent of wetland loss in Australia, widespread destruction or modification of wetland systems has occurred since European settlement. Major causes include: draining and reclamation for agriculture or urban/commercial development; mining; grazing; sedimentation and water pollution.
Construction of dams and other water storages also impacts upon wetlands. For example, some wetlands on the River Murray have been changed from having a fluctuating/flowing water cover to being permanent or semi-permanent, by regulation of the river with locks and barrages.
\BDescription:\b The Murray River \I(Peter Luck)\i
With the limited supply of surface water, about 80% of Australia depends, at least partly, on groundwater supplies. In fact, about 60% is totally dependent on groundwater and in 20% of the country groundwater is the dominant source.
Groundwater is widespread in Australia and major consolidated and unconsolidated sedimentary basins underlie 60% of the continent.
Unconsolidated sediments are the most important water bearing formations with respect to groundwater. They are mainly combinations of clays, silts, sands and gravels, more porous, more permeable and more readily recharged than other rocks. Aquifers (water bearing rock) in these sediments generally occur at depths of less than 150 metres and are often readily accessible to sources of water for recharge.
Consolidated sediments (sedimentary rocks) are also porous, due to small voids between the grains, but may not be permeable. Fractured rocks make up the remainder of Australia's groundwater provinces. In these provinces, water is transmitted through joints, faults, caverns, solution cavities and other spaces in the rock mass.
The quality of groundwater varies considerably and sources are subject to pollution in much the same way as surface supplies. In general, groundwater from shallow unconsolidated sediments is of good quality provided its source is not polluted.
Supplies from sedimentary and fractured rocks are more variable in both quality and quantity, especially in arid areas. High nitrate concentrations are common in groundwater in northern and central Australia.
\BDescription:\b Kakadu \I(DFAT)\i.
#
"Marine Water and the Fishing Zone",58,clim5.jpg,c,0
Australia, as an island nation, has one of the world's longest national coastlines. It contains over 30,000 km of mainland coast (including Tasmania), plus an equal magnitude of coast contained in the 12,000 surrounding islands and in the several hundred estuaries and coastal lagoons, lakes and bays. The total coastline measures about 70,000 km.
Adjacent to this expansive coastline is Australia's 200 mile exclusive economic marine zone (fishing zone). This zone is 16% larger than the continental land mass and is also the second largest exclusive economic marine zone in the world, being only slightly less than that of the United States of America.
This figure indicates Australia's 200 nautical mile Australian fishing zone (AFZ).
With Australia's Island Territorial Outposts taken into account, the legal Continental Shelf which Australia may claim under the provisions of the 1982 Law of the Sea Convention (LOSC) could be the largest in the world. In many cases, Australia's territorial limits reach beyond 350 nautical miles.
The resources contained in Australia's marine and coastal areas make an important contribution to Australia's economy and human activity. Claims on these resources include commercial and recreational fishing, transportation, recreation and tourism, sea bed and mineral exploration, waste disposal and species and natural phenomena preservation.
\BDescription:\b Australia's fishing zone \I(ABS)\i
#
"Surface Water Use",59,"g\9\2_0051.jpg","c","water10"
Changes in land use practices will inevitably affect the quality of water as it moves through a catchment. For example, on land cleared for agriculture, sediment and agricultural chemicals such as herbicides, pesticides and fertilisers may enter surface run-off and groundwater resources, with consequent degradation of their quality.
Water resource use can be categorised as either consumptive or non-consumptive. In the first category, the water may not necessarily be consumed, although it undergoes a transformation which reduces its usefulness as a resource.
Examples of consumptive use include water for irrigation, industry and domestic supply. Large volumes of water are also consumed by degradation from urban, industrial and agricultural waste.
This degradation (pollution) may be visible, for example, rubbish, physical degradation such as from oil slicks or inadequately treated sewage, or chemical degradation through the introduction of substances such as pesticides and detergents.
\BDescription:\b Toxic river algae in the Darling River \I(DFAT)\i
#
"Surface Water Use - (2)",60,"g\9\2_0050.jpg","c","sail10"
Pollutants are classified as either point source or diffuse. Point source refers to wastes originating from an identifiable, localised source such as a sewage treatment plant or feed lot, which are typically discharged via a pipe or drain. Diffuse pollutants such as rubbish are derived from run-off from urban or agricultural areas.
Some of the water withdrawn for consumptive uses may be returned to the atmosphere by evaporation and transpiration by plants (evapotranspiration), some may be incorporated into finished products, and some may return to the circulation system (water cycle) as drainage or groundwater.
In the non-consumptive category, water quantity and quality remain largely unaffected. Water may be harnessed for its energy potential or as a medium for some other purpose. Examples of non-consumptive use include hydro-electric power generation, navigation or flotation, recreation, nature conservation and wildlife habitat protection.
\BDescription:\b Birds swimming in the toxic river algae, Darling River \I(DFAT)\i
Groundwater is an important resource in Australia, providing about 80% of the total annual water supplies. The Great Artesian Basin is Australia's biggest single source of groundwater, underlying 22% of the continent. This basin gives an indication of how important groundwater supplies are, in that more than 4,700 flowing artesian wells have been drilled and individual flows exceeding 10 megalitres per day have been recorded.
Artesian wells are major sources of water for irrigation, livestock, industry and domestic purposes.
Groundwater is a major source of supply in Australia. As a result, some of the more intensively used aquifers are now considered to be under stress through over-development. Stress implies that the rate of extraction (use) exceeds the rate of recharge and is therefore depleting the resource.
\BDescription:\b Tea tree plantation \I(DFAT)\i
#
"Surface Water Development",62,"f\10\4_0015.jpg","c","0"
To ensure water supply under all seasonal conditions, many storages have been built. Dams and reservoirs have been built for urban water supply, hydro-electric power generation, irrigation, flood mitigation and multi-purpose development.
At last count, almost 400 large dams had been built or were under construction.
\BDescription:\b Lake Argyle Dam \I(DFAT)\i
#
"Impacts of Water Resource Development",63,"f\3\1_0012.jpg","c","0"
Water stored by dams and reservoirs has numerous uses, including recreation and assured water supply. However, water storages can be both necessary and yet damaging to the overall environment.
The most immediate effects of dam construction are the inundation and alienation of land. Stored waters may not only cover valuable agricultural or mineral resources but may also involve the loss of special habitats, scenic features or sites of historical, cultural or archaeological significance.
Within the storage itself, the change from a riverine (river) to a lacustrine (lake) ecosystem alters the biophysical conditions and may have unfortunate consequences for life forms which cannot adapt.
Water currents, strata, temperatures and other characteristics are different and this can lead to a loss of diversity and stability in fish populations, plant life and other organisms. Alternatively, some species (not always welcome) may proliferate.
Another possible impact is a build up in water nutrient loads. Reservoirs may act as settling ponds for sediment and organic matter and, with low turbidity, may stimulate the growth of algae, aquatic weeds and bacteria.
Severe eutrophication (accumulation of nutrients), especially if accompanied by decomposition of dead matter, may deplete the oxygen available to sustain life and could render the water unsuitable for some purposes.
Dams can also prevent the upstream movement of migratory fish. Even with the provision of fish ladders and other devices to bypass the obstruction, depletion of fish stocks can result.
\BDescription:\b Lake Waggaboonyah Dam, Queensland \I(DFAT)\i
#
"Downstream Effects",64,"g\9\4_0008.jpg","c","0"
Water storage and release changes streamflow, patterns of sediment deposition, water temperature and quality. These changes can impair the riverine environment and the aquatic flora and fauna dependent upon it.
Water released from lower layers of storages is colder and contains little oxygen, which can adversely affect plants and animals for a considerable distance downstream.
Water storages also disrupt the natural drainage and flood pattern of rivers. This alters the inundation pattern for wetlands, lakes and estuaries which initiate fish reproduction cycles and play host to numerous plant and animal species.
In addition, the impact of increased velocity and load on selected streams, from storage release or inter-basin transfer, at certain times, raises the likelihood of bank erosion and sedimentation downstream.
The uneven distribution of Australia's surface water resources has given rise to suggestions that surplus water from one drainage division or river basin be transferred to another where a water deficit exists. A number of inter-basin water transfers exist for urban water supply and irrigation.
The Snowy Mountains Hydro-electric Scheme in New South Wales is a well known Australian project which involves stream diversion and inter-basin water transfer. The scheme diverts approximately 60% of the discharge from the Snowy River Basin through the Great Dividing Ranges to the Murray and Murrumbidgee Rivers.
For the year 1989-90, water released to the Murray totalled 920 gigalitres while 1,042 gigalitres was released to the Murrumbidgee.
\I(Note: One gigalitre equals one thousand million litres.)\i
Other inter-basin transfers include the Thomson Scheme to supply water to Melbourne; the diversion of River Murray water to Adelaide and other South Australian areas; and the diversion of headwaters of the Glenelg River into the Wimmera-Mallee Basin in western Victoria.
\BDescription:\b Murrumbidgee River \I(Peter Luck)\i
#
"Water Transfer - (2)",66,"spread267.spr","c","0"
Most of Australia's population lives in the major cities along the coastal zones, placing large demands on the water resources in these areas. Even so, the possibility of transferring additional water inland from the coastal zone still draws attention. For example, the coastal zone of New South Wales accounts for more than 70% of that State's total annual run-off.
This table shows some of those rivers which have been considered for inland water diversion in New South Wales. Four of these, the Hunter, Hawkesbury, Shoalhaven and Bega River Basins were not considered because their water resources are already largely committed.
As with the release of water from storages, water transfers into a river may raise the likelihood of bank erosion and sedimentation. Conversely, reducing the natural drainage pattern of the source river may also have adverse impacts such as the drying out of wetlands.
#
"Irrigated Crops and Pastures",67,map43.jpg,c,0
In Australia, irrigated agriculture is the nation's largest user of water, accounting for 10,200 gigalitres or 70% of total annual water use.
This map shows the area of crops and pastures irrigated.
Of the total shown, most irrigation is still applied via furrows and/or flooding and by spraying. These are inefficient application methods because in many cases, more water is applied than is actually required by the crop. The excess can add to groundwater, raising the water table which in turn may degrade land. This degradation may simply be due to the land becoming waterlogged or because the water table is highly saline, resulting in salinity problems.
Alternatively, the water may add to run-off, increasing erosion, and be lost through evaporation.
\BDescription:\b The area of crops and pastures irrigated.
#
"Land Under Irrigation",68,"a\9\2_0060.jpg","c","thunder0"
In isolation the area of land under irrigation in Australia looks substantial. However, the total area irrigated represents less than 1% of the total area of land used for agriculture in Australia, but it represents about 6% of land under crops and 5% of the total area under crops and pastures.
Most irrigated land is located within the confines of the Murray-Darling Basin which covers parts of New South Wales, Victoria, Queensland and South Australia.
\BDescription:\b Irrigated land \I(DFAT)\i.
#
"Urban Consumption and Pollution",69,"f\5\1_0037.jpg","c","0"
Australia's population is concentrated in the primary cities around the coast and in a few larger provincial centres inland. This concentration of demand for water has required a great deal of organised effort to supply water of appropriate quantity and quality.
Urban water demands can be separated into three components: domestic use, industrial use, and commercial use. Domestic uses include drinking, cooking, washing, sewage and waste disposal, and garden/yard uses.
Commercial uses include retailing outlets, office complexes, restaurants, laundries, hotels and accommodation complexes and institutions such as schools and hospitals.
Industry may use water directly in manufacturing or for ancillary purposes, such as cooling. Many industrial processes produce waste-waters or effluents. Water contaminants include soluble components, suspensions, organic and inorganic chemical compounds, heavy metals such as lead, and may also contain bacteria and other micro-organisms.
Waste products may be single contaminants, such as acids or alkalis, or may contain a host of different contaminants as is the case with sewage.
Domestic sewage is another major source of effluent. Sewage contains numerous compounds, trace elements, bacteria known as faecal coliforms, and other pathogenic (disease producing) micro-organisms. Disposing of sewage without creating health risks or coastal pollution is therefore a problem in most of Australia's larger cities.
Even after killing bacteria/ micro-organisms, the treated effluent discharged to streams (or disposed of through ocean outfall) still contains materials harmful to the aquatic environment.
Chlorination is a method used to treat (disinfect) sewage effluent in Australia, however it is not usually treated to this level.
In Sydney for example, sewage has been discharged with only primary treatment through shoreline outfalls, polluting a number of the city's famous beaches.
In addition to illness caused to swimmers, fish caught near the outfalls have been shown to contain high levels of trace metals, pesticides and micro-organisms.
In Victoria, the sewage and industrial effluent discharged from Werribee Farm into Port Phillip Bay has also polluted marine biota.
Nutrient contamination associated with sewage outfall also destroys sea-grass beds. Major losses have occurred in Cockburn Sound, Western Australia; St. Vincent Gulf, South Australia; Westernport Bay, Victoria; and Botany Bay, New South Wales.
\BDescription:\b Industry uses water for manufacturing \I(DFAT)\i
#
"Water Usage for Different Industries",70,"spread268.spr","c","0"
Water use in a given industry shows considerable variation depending on available technology, the manufacturing procedures involved, the extent of water re-use, and management practices.
This table gives some examples of the water required to produce certain goods.
#
"Water for Recreation",71,"g\9\6_0088.jpg","c","fishing0"
Perhaps the most widespread 'in-stream' (non-consumptive) use of water is for outdoor recreation. Water based recreation activities include boating (sailing, power-boating, rowing, canoeing), fishing (all varieties), swimming (including scuba diving), water skiing and surfing.
An indication of how popular water-based recreation in Australia is was revealed in the first national survey of recreational fishing by P.A. Management Consultants, 1984. This survey found that each year about 4.5 million Australians go fishing. This is in addition to the other activities previously mentioned.
In relation to boating, the P.A. Management survey also predicted that the number of registered boats (all types) in New South Wales will reach 800,000 by the end of the century.
Water is also a major factor in enhancing the scenic quality and appeal of the recreational setting. Activities such as picnicking, bushwalking, and camping might not be as popular as they are but for the presence of water.
\BDescription:\b Fishing for recreational purposes \I(DFAT)\i
#
"Marine Water Use",72,"f\2\dfat79.jpg","c","0"
Pressures on the marine environment are exerted from agricultural and industrial activities, from mining, shipping, fishing, tourism, and from marine disposal of waste and effluent.
Australia is a major international trader and depends on sea transport (navigation lanes) for virtually all of its exports and imports.
Associated with shipping is the use of sea water as ballast (to give ships stability). Approximately 58 million tonnes of ballast comes to Australia from overseas each year. Of the water coming from overseas, 95% (56 tetralitres) is discharged from bulk carriers.
This large volume reflects Australia's trading position as a major exporter of bulk primary products such as iron ore, minerals and coal.
\BDescription:\b Loading sulphur onto a cargo ship \I(DFAT)\i
#
"Potential Water Problems",73,"a\7\d_0081.jpg","c","0"
Australia's marine areas are also used extensively for distributing freight amongst our domestic ports.
There are also significant imports and exports of crude oil and refined products. The size of these markets is about four times the volume of coastal tanker trade. Australia's heavy shipping traffic increases the incidence of oil spills.
In addition to transport, the marine environment hosts a fleet of fishing and mining vessels. Mining activities exploit valuable reserves of oil and gas, plus certain minerals (such as rutile), while fishing activities harvest a wide range of seafoods including crustacea and molluscs.
These activities (fishing and mining) not only increase the risk of oil spill, but also the volume of effluent and rubbish that ships release into the ocean.
There is also direct destruction of the marine environment by mining, for example, of hard coral and offshore tin. Damage to the marine environment can also occur from land-based industries either by dumping of waste at sea or from the release of effluents.
Tourism and recreation impacts include littering, collecting and disturbing marine organisms, and offshore sewage disposal from tourist resorts.
\BDescription:\b Damage to the environment can occur in the reefs \I(Webster Publishing)\i
#
!,!,!,!,!
3#
10,0
"Area of Australia",1,austmap.jpg,c,0
Australia comprises a land area of 7,682,300 square kilometres. The latitudinal distance between Cape York (the most northerly point of Australia) and South Point (the most southerly point on the mainland) is about 3,180 kilometres, while the latitudinal distance between Cape York and South East Cape, Tasmania, is 3,680 kilometres.
The longitudinal distance between Steep Point and Cape Byron is about 4,000 kilometres.
The area of Australia is almost as great as that of the United States of America (excluding Alaska), about 50 per cent greater than Europe (excluding the former USSR) and 32 times greater than the United Kingdom.
\BDescription:\b Map of Australia \I(Terra Forma - Andromeda Interactive)\i
#
"Coastal Areas and Time Zones of States",2,"spread422.spr","c","0"
This table shows the percentages of total areas of coastline for the different States and Territories as well as their standard time zones.
#
"Physical Features of Australia",3,"g\9\7_0088.jpg","f","0"
Australia is the lowest, flattest, and, apart from Antarctica, the driest of the continents. Unlike Europe and North America, where much of the landscape dates back to 20,000 years ago when the great ice sheets retreated, the age of landforms in Australia is generally measured in many millions of years.
This fact gives Australia a very distinctive physical geography.
The continent can be divided into three parts:
ò the Western Plateau;
ò the Central Lowlands; and
ò the Eastern Highlands.
The Western Plateau consists of very old rocks (some over 3,000 million years old), and much of it has existed as a landmass for over 500 million years. Several parts have individual 'plateau' names (for example, Kimberley, Hammersley, Arnhem Land, Yilgarn). In the Perth area, younger rocks along a coastal strip are separated from the rest by the Darling Fault escarpment. The Nullabor Plain is virtually an uplifted sea floor, a limestone plain of Miocene age (about 25 million years).
The Central Lowlands stretch from the Gulf of Carpentaria through the Great Artesian Basin to the Murray-Darling Plains. The Great Artesian Basin is filled with sedimentary rocks which hold water that enters in the wetter Eastern Highlands.
Much of the centre of Australia is flat, but there are numerous ranges (for example, Macdonnels, Musgrave) and some individual mountains of which \JAyers Rock\j (Uluru) is the best known.
Faulting and folding in this area took place long ago, the area was worn to a plain, the plain uplifted and then eroded to form the modern ranges on today's plain. In looking at \JAyers Rock\j, one remarkable thing is not so much how it got there, but that so much has been eroded from all around, to leave it there.
\BDescription:\b Kings Canyon \I(Peter Jarver)\i
#
"Faults and Plateaus",4,"g\9\16360054.jpg","c","0"
In the South Australian part of the Central Lowlands, fault movements are more recent, and the area can be considered as a number of blocks that have been moved up and down to form a series of 'ranges' (Mt Lofty, Flinders Ranges) and 'hills' (such as the Adelaide Hills), with the down faulted blocks occupied by sea (for example, Spencer Gulf) or lowlands including the lower Murray Plains.
The Eastern Highlands rise gently from central Australia towards a series of high plateaus, and even the highest part around Mt Kosciuszko (2,228 m) is part of a plateau.
There are a few younger faults and folds, such as the Lake George Fault near Canberra, and the Lapstone Monocline near Sydney.
Some plateaus in the Eastern Highlands are dissected by erosion into rugged hills, and the eastern edges of plateaus tend to form high escarpments. Many of these are united to form a Great Escarpment that runs from northern Queensland to the Victorian border. Australia's highest waterfalls (Wollombi on the Macleay, Wallaman Falls on a tributary of the Herbert, Barron Falls near Cairns, and Wentworth Falls in the Blue Mountains) all occur where rivers flow over the Great Escarpment.
For most of its length the Great Divide (separating rivers flowing to Central Australia from rivers flowing to the Pacific) runs across remarkably flat country dotted with lakes and airstrips. In eastern Victoria, however, the old plateau has been eroded into separate High Plains (such as Dargo High Plain).
\BDescription:\b Snowfields around Mt Kosciuszko \I(Jonathan King)\i.
#
"Geographical Formation of Australia",5,"g\9\7_0087.jpg","c","0"
The present topography results from a long landscape history which can conveniently be started in the Permian, about 290 million years ago, when much of Australia was glaciated by a huge ice cap.
After the ice melted, parts of the continent subsided and were covered with sediment to form sedimentary basins such as the Great Artesian Basin. By early Cretaceous times, about 140 million years ago, Australia was already so flat and low that a major rise in sea level divided it into three landmasses as the shallow Cretaceous sea spread over the land.
In the following Tertiary times, Australia can be regarded as a landscape of broad swells varied by a number of sedimentary basins (Murray, Gippsland, Eucla, Carpentaria, Lake Eyre and other basins). These slowly filled up and some are now sources of coal or oil. The Eastern Highlands were uplifted about this time.
Throughout the Tertiary, volcanoes erupted in eastern Australia. Some individual volcanoes were the size of modern Vesuvius, and huge lava plains covered up large areas. Volcanic activity continued up to a few thousand years ago in Victoria and Queensland.
Australia's youngest volcano is Mount Gambier in South Australia, about 6,000 years old.
\BDescription:\b An example of the uniqueness of Australia's geography \I(Peter Jarver)\i
Between 55 and 10 million years ago Australia drifted across the surface of the earth as a plate, moving north from a position once adjacent to Antarctica. There have been many changes in the climate of Australia in the past, but oddly these are not due to changing latitude (associated with global scale plate movements).
Even when Australia was close to the South Pole, the climate was relatively warm and wet, and this persisted for a long time despite changes in latitude. It was probably under this climate that the deep weathered, iron-rich profiles that characterise much of Australia were formed.
Aridity only seems to have set in after Australia reached its present latitude, and the northern part was probably never arid.
\BDescription:\b Garden of Eden, Kings Canyon \I(Peter Jarver)\i
Today a large part of Australia is arid or semi-arid. Sand dunes are mostly longitudinal and are aligned with dominant wind directions associated with the regular passage of high pressure cells (anticyclones).
The dunes are mostly fixed now. Stony deserts or gibber plains (covered with small stones or 'gibbers') occupy a larger area than the dunefields.
Salt lakes occur in many low positions, in places following lines of ancient drainage. They are often associated with lunettes, dunes formed on the downwind side of lakes. Many important finds of Aboriginal prehistory have been made in lunettes.
Despite the prevalence of arid conditions today, real aridity seems to be geologically young, with no dunes or salt lakes older than a million years.
The past few million years were notable for the Quaternary ice age. There were many glacial and interglacial periods (over 20) during this time, the last glacial period occurring about 20,000 years ago. In Tasmania there is evidence of three different glaciations: the last glaciation, one sometime in the Quaternary, and one in the Tertiary. In mainland Australia there is evidence of only the last glaciation, and the ice then covered only 25 sq km, in the vicinity of Mt Kosciuszko.
"Why Australia is the Shape That it is",8,6_0077.jpg,c,0
The broad shape of Australia has been influenced over long periods by earth movements associated with large tectonic processes. However, much of the detail has been carved by river erosion. A significant number of Australia's rivers, like the Diamantina River, drain inland. While they may be eroding their valleys near their highland sources, their lower courses are filling up with alluvium, and the rivers often end in salt lakes which are dry for most of the time.
Other rivers reach the sea, and have dissected a broad near-coast region into plateaus, hills and valleys. Many of the features of the drainage pattern of Australia have a very long history, and some individual valleys have maintained their position for hundreds of millions of years.
The salt lakes of the Yilgarn Plateau in Western Australia are the remnants of a drainage pattern that was active before continental drift separated Australia from Antarctica.
During the last ice age, sea level was over 100 m lower than it is today; the current outer reef area of the Great Barrier Reef would have been the coast at the time. The rivers tended to cut down to the lower level, especially towards the sea. When the sea level rose again, some of the lower valleys were drowned, making fine harbours (for example, Sydney Harbour), while others tended to fill with alluvium as the sea rose, making the typical lowland valleys around the Australian coast.
Coastal geomorphology is also largely the result of the accumulation of sediment in drowned coasts. In some areas, such as Ninety Mile Beach (Victoria) or the Coorong (South Australia), there are beaches made simply from this accumulation. In much of the east there is a characteristic alternation of rocky headland and long beach, backed by plains filled with river and marine sediments.
The offshore shape of Australia, revealed in isobath contours, results mainly from the pattern of break-up of the super-continent of which Australia was once a part. In some areas, such as the Great Australian Bight, there is a broad continental shelf bounded by a steeper continental slope. In other areas, like south-east New South Wales around Merimbula and much of the Tasmanian coastline, the continental shelf is very narrow, sometimes coming to within 20 nautical miles of the coast.
The Queensland coast is bounded by a broad plateau on which the \JGreat Barrier Reef\j has grown in only the last two million years. In South Australia the continental shelf is grooved by submarine canyons.
The Australian landforms of today are thus seen to result from long-continued processes in a unique setting, giving rise to typical Australian landscapes, which in turn provide the physical basis for the distribution and nature of biological and human activity in Australia.
\BDescription:\b Norman River near the Gulf of Carpentaria \I(DFAT)\i
#
"Rivers of Australia",9,"a\3\mrrmbge.jpg","c","0"
The rivers of Australia may be divided into two major classes: those of the coastal margins with moderate rates of fall and those of the central plains with very slight fall.
Of the rivers of the east coast, the longest in Queensland are the Burdekin and the Fitzroy, while the Hunter is the largest coastal river in New South Wales. The longest river system in Australia is the Murray-Darling which drains part of Queensland, the major part of New South Wales and a large part of Victoria, finally flowing into the arm of the sea known as Lake Alexandrina, on the eastern side of the South Australian coast.
The length of the Murray is about 2,520 kilometres and the Darling and Upper Darling together are also just over 2,000 kilometres long.
The rivers of the north-west coast of Australia, for example the Murchison, Gascoyne, Ashburton, Fortescue, De Grey, Fitzroy, Drysdale and Ord, are of considerable length. So also are those rivers in the Northern Territory, for example the Victoria and Daly, and those on the Queensland side of the Gulf of Carpentaria, such as the Gregory, Leichhardt, Cloncurry, Gilbert and Mitchell. The rivers of Tasmania have short and rapid courses, as might be expected from the configuration of the land.
\BDescription:\b Murrumbidgee River \I(Peter Luck)\i
#
"Lakes of Australia",10,"g\9\1_0078.jpg","f","0"
There are many types of lakes in Australia, the largest being drainage sumps from the internal rivers. In dry seasons these lakes finally become beds of salt and dry mud.
The largest are Lake Eyre, 9,500 square kilometres; Lake Torrens, 5,900 square kilometres; and Lake Gairdner, 4,300 square kilometres.
Other lake types are glacial, most common in Tasmania; volcanic crater lakes, predominantly in Victoria and Queensland; fault angle lakes, of which Lake George near \JCanberra\j is a good example; and coastal lakes formed by marine damming of valleys.
\BDescription:\b Lake Jindabyne \I(DFAT)\i
#
!,!,!,!,!
4#
9,0
"Concern for Our Plants and Animals",1,"g\9\ka_0014.jpg","c","0"
Apart from providing food and oxygen necessary for life, flora and fauna are integral in maintaining the balance in the world's ecological (life-support) systems.
Ecosystems, on land and in water, can be regarded as dynamic systems resulting from interactions between organisms, both biotic and abiotic, the atmosphere, soil, water, energy and the physical environment. These interactions perform many functions including energy transfers, nutrient recycling, soil regeneration and air and water cleansing.
Human survival and well-being depends on the continued functioning of these essential life-support systems.
There is growing concern amongst the human population about habitat destruction and species extinction.
The extent of change which ecosystems can withstand before their regenerative capacity (balance) is lost is not known. However there is evidence that in many cases human impacts have already exceeded the environment's limits.
For example, land clearing activities associated with farming and urban development have resulted in the loss of forest ecosystems in some areas.
Plants and animals remain vital to human society not only as resources but also for social and cultural reasons.
"Australian Native Plants and Animals",2,"g\9\d_0009.jpg","c","0"
The Australian continent and its islands support a diverse array of flora and fauna. More than 1 million species (including micro-organisms) are thought to live in Australia, but less than 15 per cent have been formally described. Many of these plants and animals occur naturally only in Australia. Estimated statistics include:
* From approximately 20,000 species of higher plants, more than 85% are found only in Australia;
* From approximately 1,000 species of birds, 45% are found only in Australia;
* Australia has two of the world's three monotremes (egg laying mammals);
* From approximately 268 mammals/marsupials, 84% are found only in Australia;
* From approximately 973 species of reptiles/amphibians, 89% of reptiles and 93% of frogs are endemic, the reptile fauna of Australian deserts being the richest in the world;
* Australia has approximately 54,000 known species of insects with at least as many still to be identified and many other invertebrates are equally poorly known (80% of tiger beetles are found only in Australia);
* Australia has 4,100 species of fish and tens of thousands of species of molluscs (of the 600 inshore species of finfish in the southern temperate zone, approximately 85% are found only in Australian waters); the flora and fauna of Australian coastal waters is one of the most diverse in the world.
\BDescription:\b The Emu \I(Webster Publishing)\i
#
"Plants and Medicine",3,"g\9\d_0018.jpg","c","0"
In the United States, approximately 25% of medical prescriptions filled are for drugs derived from plants. Even so, scientists have only examined about 5,000 of the world's 250,000 flowering plants for their pharmacological value.
Ensuring the survival of plant and animal habitats not only helps preserve biological/genetic diversity but also enables ecosystems to endure.
With our dependence on drugs derived from plants, it is somewhat sobering to discover that 17% of the 20,000 species of plants known to exist in Australia are either rare or threatened.
\BDescription:\b The Bottlebrush \I(Webster Publishing)\i
#
"Marine Plants and Animals",4,"g\9\sth-rite.jpg","c","0"
Maintaining the marine environment and monitoring marine plant and animal populations is just as important for their survival as for any of the terrestrial species.
Australia exploits its marine biodiversity - with commercial harvesting of four species of crabs, four of lobster, 12 of prawn, three each of abalone and scallops and about 300 species of finfish. Under good management, the number of fish that commercial fishers can take can be sustainable, especially if they use species that are present in large numbers and have high reproductive rates.
Owing largely to economic activities, some marine species have been, or are being threatened with extinction. Although now banned in Australian waters, commercial hunting of whales and seals has had a marked impact on some species.
Southern Right Whales in the Cape Leeuwin-Cape Arid area of Western Australia migrate, breed and feed in large numbers, but pods have been significantly reduced by whaling.
Today, only a small number of whales are seen, although sightings are increasing.
\BDescription:\b Southern Right Whale \I(Gum Tree Graphics)\i
#
"Introduced Species",5,"spread266.spr","c","0"
One impact which is recognised as having a great influence on native flora and fauna is the increasing number of introduced species present in native bushlands. These include plants such as mission grass and animals such as foxes and rabbits.
At least 15% of Australia's flora now consists of introduced species. About half of these plant species invade native vegetation and about one-quarter are regarded as serious environmental weeds or have the potential to be serious weeds. Almost all of Australia's native vegetation has been, or is likely to be, invaded by exotic species that could result in changes to the structure, species composition, fire frequency and abundance of native communities.
This table gives details of the number and percentage of introduced plant species which have become naturalised in various places.
Of all the states, Tasmania has the highest proportion of naturalised introduced species, comprising almost one third of its total flora.
#
"Introduced Species - (2)",6,"0","Prickly Pear invasion","pear.avi"
Not all introduced species invade and threaten native plant communities. For example, an introduced plant may become established on land which is devoid of native vegetation.
Of the 825 introduced species in Victoria, 412 are established amongst native vegetation. Out of these, 69 (8%) are considered a very serious threat, 15% a serious threat, 8% a potential threat and the remainder are considered as non-threatening.
Regarding birds, there are 96 species which are known to have been introduced by humans, 32 of which have become established. Examples of established introduced birds include the sparrow, starling and Mallard duck.
In a natural environment, there are checks and balances such as natural predators and diseases to control population numbers, however these are not present for many of the species of animals introduced into Australia. As a result, introduced species are increasing in number, often at the expense of native species. They continue to survive unchecked until drought occurs.
\BViddescription:\b Prickly Pear (Film Australia)
#
"Introduced Species - (3)",7,"d\10\d_0095.jpg","c","eat10"
The impact of introduced animals is quite large and includes competition with native species for shelter, food and water; changes to habitats; increases in soil erosion; unnatural predation on smaller native species; and the spread of disease.
Regardless of why mammals were introduced, where they have become established and are thriving they pose a threat to the flora and fauna which originally inhabited the environment. At least 18 exotic mammals have established feral populations in Australia, including cats, dogs, foxes, pigs, water buffalo, donkeys, goats and horses.
\BDescription:\b A good example of an introduced mammal is the goat \I(Webster Publishing)\i
#
"Introduced Species - (4)",8,"d\10\cat.jpg","c","0"
Long term control efforts against introduced species have been unsuccessful due to such factors as: inadequate resources, inadequate technology for detection of species and destruction at low density, and reinfestation by introduced species through immigration.
Some of the introduced mammals which have adapted and become established in Australia include the black rat, the house mouse, the red fox, the domestic cat, the European rabbit, and feral horses, donkeys and pigs. These introduced mammals have all become abundant in different parts of the country.
Cats and foxes prey on a wide range of native animals and have been implicated in the decline, if not the extinction, of a number of species.
\BDescription:\b The domestic cat \I(I T Mahood - Nature Focus)\i
#
"Introduced Fish",9,"g\9\d_0083.jpg","c","0"
Australia's aquatic environment has also seen the introduction of numerous fish species. For example, the European carp is well established in the Murray River to the detriment of native fish species. The most widespread of introduced exotic fish include trout, mosquito fish, goldfish, redfine perch and tench.
Exotic fish have been implicated in the decline of nine endangered, eight vulnerable and five rare or common native fish species.
Approximately 20 exotic marine fish have been introduced in Australia either deliberately, or through ballast water discharge.
\BDescription:\b Australia's aquatic environment has seen the introduction of numerous fish species \I(Webster Publishing)\i.
#
!,!,!,!,!
5#
22,This is a null field
"Importance of Trees",1,d_0074.jpg,c,forest20
Trees are a most important feature of the world in which we work, live and play. They influence our surroundings by modifying the climate, changing the appearance of the land, holding the soil and sheltering animal life. Perhaps the most obvious environmental effect of trees is visual, in the way they alter and almost invariably improve the appearance of the land.
A special feature of trees is the way they can help modify the climate around them. Temperature ranges in a forest stand are smaller than those in the open. The maximum temperatures are lower and the minimum temperatures are higher.
In one study in the Northern Tablelands, the temperature on the coldest night of the year was minus 11 degrees Celsius in the open, compared with minus 6 degrees Celsius under a nearby stand of young pine trees.
Trees can be formed into windbreaks to help slow wind speed in farming and recreation areas. Such windbreaks can more than halve the wind speed in the open for distances of 15 to 20 times the height of the windbreak. A break consisting of trees 20 metres high will have a significant effect on wind speed for 300 to 400 metres down-wind.
In windy localities, windbreaks can improve the health of livestock, increase the yield of crops and reduce evaporation from farm dams.
\BDescription:\b Trees are a most important feature of the world in which we work, live and play \I(Webster Publishing)\i.
#
"Trees and our Environment",2,"g\9\d_0067.jpg","c","0"
Trees play an important role in many of the processes and cycles of the environment. They help maintain water purity by filtering water and preventing impurities like soil particles, run-off debris and leaf litter from entering waterways. The roots of trees and other plants help combat soil erosion by minimising soil loss caused by wind, rain or water flow.
In the process of growing, trees perform an extremely important function when they take carbon dioxide from the air and replace it with oxygen. They also contribute on a small scale to removing certain pollutant gases from the air, such as ozone and sulphur dioxide. In this way, young vigorous trees help freshen the air, as do other actively growing green plants.
\BDescription:\b Trees play an important role in many of the processes and cycles of the environment \I(Webster Publishing)\i.
#
"Forest Animals",3,"g\9\dfat36.jpg","c","0"
Forests provide homes for a vast array of wildlife, including birds, reptiles, insects and a large variety of mammals. Wildlife and the flora that surrounds them do not lead separate lives - they depend on each other.
A large percentage of animals and birds use forest trees, particularly the eucalypts, as their homes. They nest or rest in hollows that develop when branches break off the tree and termites eat away the wood, or fire burns holes in the trunk. Other animals build nests in the trees from leaves and twigs, or from grasses and bits of bark.
Trees also provide protection. Their leafy canopy helps conceal many animals from their predators. In their turn, the animals help the forest trees.
Sugar gliders, other small possums and bats carry pollen to germinate new trees while fruit-eating pigeons spread seeds during their nomadic wanderings. As the trees grow, honeyeaters help maintain the natural balance by feeding on leaf-eating insects.
\BDescription:\b A Possum \I(DFAT)\i.
#
"Australian Trees and the First Europeans",4,"f\8\r4714.jpg","c","0"
Even before the first occupation of the continent by Aboriginal people, the land continually evolved and adapted, in response to changes in the climate and other environmental conditions. Aboriginal people introduced the first form of active forest management, using fire to regenerate the land and help with hunting.
When the First Fleet anchored in Sydney Cove in 1788, about half of what is now New South Wales was covered by forests. The new settlers, needing timber to build houses and cleared land to grow food, began cutting down the trees. This was the beginning of the destruction of the State's forests that saw some 40 million hectares of trees reduced to a third of that area.
The native trees of New South Wales were unfamiliar to the early settlers and their value was unknown. In 1791 \JGovernor Phillip\j sent a trial shipment of local timbers to England to test their properties and quality. The British Admiralty was so impressed with the results that it ordered convict ships to bring back to England as much timber as possible for use in His Majesty's dockyards.
Although the native timber was plentiful, the colony's builders and cabinet makers found it difficult to use. Workmen, who had been blunting their tools on the local hardwoods, welcomed the discovery of the soft and beautiful wood of the Red Cedar tree.
As a result, a large number of these highly desired 'red gold' trees were felled. The extent of this felling was so severe that in 1795 \JGovernor Hunter\j issued regulations to control the felling of cedar trees along the Hawkesbury River.
The clearing of land for settlement in other areas of the colony was quick and indiscriminate. The destruction of forests was so unrestricted that in 1803 \JGovernor King\j, worried about erosion along the Hawkesbury River, issued Australia's first 'tree preservation' order.
It prohibited the cutting down of trees and shrubs within 'two rods' (10 metres) of river banks, an enlightened action that could be regarded as the first step taken by the newcomers to Australia to protect the environment.
A number of regulations were issued in subsequent years to control timber-getting. Licences were needed to cut trees on Crown lands and a royalty fee was introduced. By 1820 timber getters not only needed permission to operate; the quantity of trees they could cut was specified.
Since European settlement, Australia has lost an estimated 75 per cent of its rainforests, 40 per cent of its total forest area and 70 per cent of all native vegetation has been removed or modified.
\BDescription:\b Early settlers cleared much timber to build houses \I(RAHS)\i
#
"Beginnings of Forest Management",5,r4714.jpg,c,0
In the early 1870s the Government set aside the first areas of Crown land to be conserved for future timber production and not to be cleared, marking the beginning of forest management in New South Wales. By 1882 about 1.4 million hectares of forest had been preserved.
In the early years of the twentieth century, forestry was recognised as a profession and the Forestry Acts of 1909 and 1916 laid down the basis of the economic management of the forests and established the Forestry Commission of New South Wales.
Control passed from the hands of public surveyors and clerical administrators to professional foresters who were concerned with managing forests, rather than simply administering timber sales. By 1919, the Forestry Commission was responsible for 2 million hectares of State forest and timber reserves.
\BDescription:\b Early settlers cleared much timber to build houses \I(RAHS)\i
#
"Forests and the Greenhouse Effect",6,"g\9\kl_0060.jpg","c","0"
Forests play an important role in slowing down the greenhouse effect. Trees help to decrease the amount of carbon dioxide in the atmosphere. Carbon dioxide, along with other gases, contributes to the greenhouse effect which may lead to major changes in our climate.
Permanent increases in temperatures around the world could cause disastrous problems, including flooding of coastal areas, the disappearance of many islands and the spread of desert areas. It may also lead to major changes in vegetation, making some farmland useless and other areas bloom.
Scientists argue that since the nineteenth century the concentration of carbon dioxide in the atmosphere has gone up markedly. The reasons given are many. The burning of fossil fuels containing carbon, such as coal and oil, while necessary for the economy, is believed to have led to a significant increase in carbon dioxide in the atmosphere.
At the same time, much of the forests that might have helped remove the carbon dioxide from the air have been replaced by farmland, grazing land, factories and cities.
\BDescription:\b Trees play an important role in slowing down the greenhouse effect
#
"Trees and Carbon Dioxide",7,"g\9\d_0027.jpg","c","0"
Trees 'inhale' air and 'exhale' oxygen. A tree's ability to remove carbon dioxide from the air and increase the amount of oxygen is one of the wonders of nature.
Trees use chlorophyll in their leaves to transform the carbon dioxide, along with water from the soil, into sucrose and oxygen. The sucrose is used as food for the trees while the oxygen is returned to the atmosphere. Through this process, called photosynthesis, carbon dioxide becomes part of the wood in the trees.
The rate of accumulation of the carbon in the organic matter, and the simultaneous removal of carbon dioxide from the atmosphere, are much greater in rapidly growing young forests than in a mature forest.
Pine plantations, usually established on cleared farmland, are particularly useful in reducing carbon dioxide. The plantations increase the area of forest growth and are harvested more quickly than other species, allowing new plantings.
Mature forests have a much slower growing rate leading to smaller accumulations of carbon. Furthermore, the leaves and boughs that are shed by mature trees decompose, releasing carbon dioxide into the atmosphere. This makes them less efficient removers of carbon dioxide from the atmosphere.
Logging some mature trees to allow the regeneration of new trees will lead to increases in the amount of carbon accumulating in the forest, while maintaining the biodiversity.
\BDescription:\b Trees remove carbon dioxide from the air \I(Webster Publishing)\i.
#
"Storing Carbon in Trees",8,"g\9\tony17.jpg","c","hammer10"
Trees are a kind of long term storage system for carbon. Carbon can remain fixed in wood for generations when it is utilised in building houses or manufacturing furniture.
Steel and other manufactured products lead to increases in carbon dioxide. Carbon is released when energy is used in their manufacture, but of course many of these products are essential.
In many cases when we currently use steel, we can use wood. For example, manufacturing the steel framing used in a typical house would lead to the production of 2.9 tonnes of carbon. Switching to timber framing means a total of 7.5 tonnes of carbon are removed from the atmosphere and stored in the wood for the life of the house.
Using timber cladding on the house also leads to the storage of carbon, while the energy used in manufacturing bricks or aluminium cladding releases large amounts of carbon into the atmosphere.
Timber products and the forests they come from are a part of the solution to the greenhouse problem.
\BDescription:\b Timber is used for construction work \I(Webster Publishing)\i.
Sustaining the resources of a forest means handing on an undiminished forest from one generation to the next. This does not mean leaving trees as they are. Trees are living creatures that grow and die.
As the natural cycle sees trees grow and die, so a forest can be managed to follow this cycle, where some trees are cut and other trees grow on. With the proper distribution of trees of different ages and sizes, a certain number can be cut every year without diminishing the forest. We call this process sustained yield.
Sustained yield looks at the forest as a whole, over a long period of time. Only the number of trees that will keep the age and size of the forest constant are cut. The next year other trees in other parts of the forest will be ready for logging while the regrowth trees will be a year older and still growing.
Managing the logging of trees to maintain the quality and quantity of the forest over time will ensure that the community has the timber it needs, while sustaining the resources of the forest.
\BDescription:\b We must maintain our forests \I(DFAT)\i.
#
"Wood is a Renewable Resource",10,"g\9\d_0075.jpg","c","0"
Some resources, like iron ore, coal, bauxite and oil are in reasonable supply in Australia, but they are not renewable. We need to use large amounts of energy to process these resources and this generates greenhouse gases. In addition, when these products have outlived their intended purpose, a lot of energy is required to recycle them. If they are dumped, they take a long time to break down, adding to pollution.
All of these problems are minimised when we use forest products. Little energy is needed to convert a log into a house frame; wooden furniture can be repaired and recycled indefinitely and, in the end, the wood is biodegradable.
The best part of using timber is that it is renewable. Trees grow again, and the only source of energy they need is the sun.
\BDescription:\b Wood - a renewable resource \I(Webster Publishing)\i.
#
"Forests and the Future",11,"b\1\3_0029.jpg","c","0"
Through science, we can ensure the future of our forests and find the most effective methods to keep them thriving, while obtaining the best use from the trees used for timber.
While wood production might once have seemed the main benefit of forests to most people, community awareness of the many other benefits forests provide has heightened dramatically in recent years. Our priorities have changed to reflect this, and maintaining biodiversity (all the elements that make up a forest ecosystem) has increasingly become the central focus of our forest management and research.
Research is an integral part of forestry. As researchers discover more and more about forest ecosystems and the wood which comes from them, foresters can translate this into better management for the present and the future of our forests.
\BDescription:\b Forest and farmland \I(DFAT)\i.
#
"What is a Rainforest?",12,"g\9\4_0037.jpg","c","0"
As the name suggests, a rainforest is a forest that grows in areas of high rainfall. We define a forest as an area covered by trees that grow so close together that the canopy is interlocked in such a way that direct sunlight does not reach the ground except in small patches. From the air you would not see the ground at all.
Rainforest grows where there is a high and consistent rainfall. Generally a rainforest needs at least 1500 mm of rainfall a year. More importantly, the rain has to fall consistently and frequently.
In Australia, rainforest can also be defined by the species of plants present or absent. For example, gum trees do not occur in a rainforest except at its margin, where isolated gum trees will either have been trapped by the expanding margin of the rainforest, or where they are expanding into the retreating rainforest. As a result of fire, the boundary of a rainforest is usually distinct.
Many people picture a rainforest as a lush, deep-green, dimly lit, humid jungle made up of tall evergreen trees with hanging rope-like vines. This is a tropical rainforest. In Australia we also have subtropical and temperate rainforests. All three are found only in patches with eucalypt forests between.
\BDescription:\b Rainforest at Minnamurra Falls, NSW \I(DFAT)\i
#
"Rainforests in Australia",13,"a\7\6_0084.jpg","c","water30"
In Australia, tropical rainforests grow in Queensland between the tip of Cape York Peninsula and Ingham, near Townsville.
Subtropical rainforests stretch from near Mackay in Queensland to below \JWollongong\j in New South Wales, near Sydney. Bunya and Hoop Pines are common in subtropical rainforests.
Further south, in the temperate rainforests, the most common trees are called Antarctic Beech. The temperate rainforests grow in parts of Victoria, and in western and north-eastern Tasmania.
\BDescription:\b Mangroves - Cape York Peninsula \I(DFAT)\i
#
"History of the Rainforest",14,"c\8\dino1.jpg","c","0"
In 1770, when \JCaptain Cook\j sailed along the Australian coast, 3.6 million hectares of rainforest was growing in Australia. We have half of that today. Before Europeans arrived in Australia, changes in both the arrangement of the world's land masses and climate caused changes in Australia's rainforest. Clearing for agriculture has been the main cause for the decline during the last 200 years. It is estimated that Australia has lost 75 per cent of its rainforest area since then.
Over 200 million years ago, Australia, Africa, South America, India and Antarctica were one continent - Gondwana. Australia and Antarctica broke away from Gondwana about 65 million years ago and then 40 million years ago, they too separated. Australia moved northwards and the climate became drier, causing changes in both where plants grew in Australia and the type that could continue to grow in a changed climate.
The tropical rainforest we see today has evolved from the sort that was on Gondwana 60 or even 80 million years ago. There are also some plants that have arrived in the last 12 million years from close land links with South-east Asia.
\BDescription:\b The breakup of Gondwana \I(John Long)\i
#
"Rainforest and Fire",15,"0","Fires can completely destroy rainforests","fire2.avi"
Many of the plants of the temperate rainforests were widespread on mainland Australia two to 66 million years ago. As the climate became drier, the frequency of bushfires increased. The rainforests contracted and many species became extinct. Species that survived did so in isolated valleys and mountain tops.
With the arrival of Aboriginal people and their use of fire as a method of hunting, the frequency of bushfires increased and the area covered by rainforests became even smaller. Now we have European land use with widespread clearing for agriculture, further reducing the size of our rainforests.
Uncontrolled fires in Australian rainforests are relatively rare because there is generally no suitable fuel in the understorey. However, when the margins of rainforests are exposed regularly to fire in the dry season, the trees and shrubs common on the edges of rainforest are replaced by fire-resistant gum trees and grasses. Fire, therefore, seems to be the main force defining rainforest boundaries.
\BViddescription:\b Rainforests and fires (Film Australia)
Rainforests are subject to a number of natural disturbances which result in various changes to the forest. Some of these changes are rapid, such as recovery from damage caused by a single tree falling. Lightning strikes, landslides resulting from excessive rain and even occasional drought also periodically disturb and damage parts of the forest.
Cyclones are an example of a major catastrophic natural event that occurs irregularly and can cause significant change in a rainforest. Cyclone damage is usually restricted to the canopy but it produces a lot of litter, and with dry weather conditions, fires can follow.
\BDescription:\b A goat \I(Webster Publishing)\i
#
"Human Disturbances",17,"g\8\2_0055.jpg","c","0"
Logging, soil erosion, stream pollution, the location of roads and power lines, fragmentation due to clearing for agriculture, and the introduction of diseases, weeds and feral animals are all disturbances that humans can inflict on rainforests.
Some people believe that the disturbances we are responsible for can be controlled so that the result is similar to the effect of cyclones and natural tree fall. Schemes for logging a forest on a 'sustainable' basis are designed to cause disturbance at the same level as one major natural disturbance about every 40 years.
Recent research suggests that such regular and intense logging is not suitable and will in time deplete rainforest plant and animal diversity. If logging is allowed on an extensive, ongoing basis, the resulting damage includes removal of seed trees, reduction of food and nesting sites for animals, and damage to the soil surface by road construction and use of heavy machinery, which also increases water run-off and so causes greater soil erosion.
\BDescription:\b Work being carried out in a forest \I(DFAT)\i.
#
"Rainforests Coping with Disturbances",18,"g\9\7_0089.jpg","c","water20"
We do not know the age of many rainforest trees. Some emergents (the tallest of the rainforest trees) probably flower, and hence produce seeds, for the first time after 50 to 60 years. Some trees probably live for 200 to 500 years. It may take about 800 years for all the richness of a rainforest to form again in a cleared area. This regeneration is only possible if the disturbance is of a type with which the rainforest has evolved strategies to cope.
Predicting how a rainforest reacts to and recovers from disturbance is essential for forest management. However, because change occurs naturally in a rainforest and we can't yet predict the effects of disturbances, we do not have the knowledge at present to ensure that rainforests will be able to regenerate from the combination of natural and human disturbances.
\BDescription:\b Rainforest \I(Peter Jarver)\i.
#
"Harvesting Rainforest Timbers",19,"0","g","0"
Harvesting of Australian rainforest timbers has almost stopped but we continue to import tropical timber. To overcome this contradiction of standards, Australia, like many other developed countries, is considering imposing bans on tropical rainforest timbers.
The countries which rely on timber to generate money to purchase food and other essentials for life may respond to a timber ban by clearing rainforest for agriculture. A better solution might be for the international community to accept some rainforest logging while assisting these countries in defining adequate reserves of unlogged forests and to develop logging techniques which are genuinely sustainable.
It may also be necessary to organise the international timber market so that producing countries receive a fair price for their timber.
#
"Why We Should Conserve Rainforests",20,"g\9\2_0032.jpg","c","forest20"
People have different answers to the question of why we should conserve rainforests. To some it is enough that they exist as part of the diversity of our planet and therefore we, as just one species on earth, do not have the right to knowingly destroy any ecosystem.
Some people say we need to conserve rainforests because we have not studied them fully and do not understand what is there and how the whole complex system works. If we can strive to understand the complex inter-relationships of rainforests, there is a greater likelihood that we will be able to more wisely manage these and other resources of our planet.
\BDescription:\b We should conserve rainforests \I(DFAT)\i.
#
"Conservation for Economic Reasons",21,"g\9\dfat31.jpg","c","0"
Many people believe that the key to conserving any of the planet's resources is to find an economical use for them. Since rainforests have a biological richness that gives them an immeasurable aesthetic value, they have potential use in recreation and tourism as people seek to visit and enjoy such an environment.
The use of rainforests as a tourist attraction, which could form the basis of an industry, is seen as a worthwhile reason by many to fight for rainforest conservation.
Some parts of the rainforest also have established and potential economic values. Apart from commodities such as timber, food and drugs already in use, there could be new foods and drugs, and a source of new genes to hybridise with some of our existing highly selected but disease-prone cultivars.
Conflicts arise when there are differences in opinion about the importance of the different types of 'value' placed on rainforests. Ideally, we should be able to manage the resource properly for as many uses as possible. Such wise management requires more research to gather the necessary information about this complex, interdependent system of plants, animals, soils and climate.
\BDescription:\b Many animals depend on the rainforest for survival \I(DFAT)\i
#
"Australia's Special Conservation Responsibilities",22,"g\10\6_0072.jpg","c","0"
Australia is the only country that has a full suite of rainforests from tropical to temperate; it is also the only country in the western world that has rainforests. As such, Australia has the responsibility to keep its rainforests intact.
Some countries are so poor that they are tempted into turning their forests into money. In many cases they will regret this in the future when they are faced with ruined fisheries and huge bills for soil restoration. Australia is sufficiently prosperous to take a long term view and use its forests carefully and sustainably.
Fortunately in Australia, our focus is now on conserving our remaining rainforest. Interest is increasing in the reafforestation of once-cleared areas, in establishing plantations of valuable timber species, in the restoration of logged or degraded forests, and in management and further research.
\BDescription:\b Rainforest in Queensland \I(DFAT)\i
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6#
11,0
"The Kangaroo",1,"g\10\dfat23.jpg","c","0"
Of all Australian native wildlife, it is the kangaroo which provokes the greatest emotion. Along with the emu it features on our national coat of arms. It is used to symbolise the spirit of Australia on everything from our airlines to our "made in Australia" products. It is used by industry, government and sporting organisations.
Despite their natural and cultural significance, millions of kangaroos are killed each year. They are killed for two main reasons: as a form of pest control; and for commercial purposes. Every year, Australian Governments set quotas for the amount of kangaroos allowed to be killed. The quota in 1992 stood at 5.2 million annually.
This section looks at some of the reasons why the kangaroo is being killed, the impacts on the kangaroo population and the environment. At present, the kangaroo industry has few checks on it, so we also discuss the possibility of kangaroo farming to see whether this could be commercially and environmentally viable.
\BDescription:\b \I(DFAT)\i
This section on kangaroos was taken from \IKangaroos, Our Wildlife Heritage, Not an Exploitable Resource\i published by the Australian Wildlife Protection Council.
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"Which Kangaroos are Killed Commercially?",2,"g\10\dfat26.jpg","c","0"
It is often a surprise to people studying the kangaroo debate for the first time to discover that the kangaroo industry kills up to 10 species of kangaroos and wallabies.
Kangaroos which are commercially killed include the Red kangaroo, the Eastern Grey kangaroo, the Western Grey kangaroo, the wallaroo or euro, the Whiptail wallaby, the Rufous wallaby or Tasmanian pademelon, and the Red-necked or Bennett's wallaby.
Queensland sometimes allows the commercial killing of a further three species of wallaby: the Sandy wallaby or Agile wallaby, the Black-striped wallaby and the Swamp wallaby. However in 1992, these wallabies were killed for pest control purposes only.
\BDescription:\b \I(DFAT)\i
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"Kangaroo Management",3,"g\10\d_0060.jpg","c","0"
Since 1985, the Federal and State Governments have stated two major aims for the management of kangaroos:
* To maintain populations of kangaroos over their natural range, and
* To contain the harmful effects of kangaroos on other land management practices.
(Australia's National Plan for Kangaroo Management - CONCOM 1985.)
Due to the effects of the kangaroo industry and the destruction of natural kangaroo habitats through intensive agriculture, these aims are not necessarily being achieved at present.
\BDescription:\b \I(Webster Publishing)\i
#
"Are We Maintaining Kangaroo Populations?",4,"c\9\31_0008.jpg","c","0"
There is considerable argument over the size of our current kangaroo population. Advocates of the kangaroo industry point to the pastoral areas of Australia and argue that there are more kangaroos now than at the time of European settlement, however it is difficult to obtain accurate numbers for the size of kangaroo populations.
We do know that kangaroo and wallaby numbers have been greatly reduced in most areas of intensive agriculture. Some species of commercially killed kangaroos and wallabies are even locally extinct in parts of their natural range.
The effect of lost kangaroo habitat in Western Australia will result in kangaroos disappearing from much of the West Australian wheatbelt over the next 100 years unless the remnant vegetation is managed and native plants are regenerated. At present, five species of kangaroos, wallabies and their relatives are extinct throughout the wheatbelt, and four species are found only in a few locations. This has resulted from loss of habitat and severe fox predation.
The case in Western Australia shows that we are not maintaining kangaroo populations over their natural range.
\BDescription:\b \I(David Ireland)\i
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"Are We Containing the Kangaroos?",5,"g\10\d_0061.jpg","c","sheep0"
One of the aims of kangaroo management stated by Federal and State Governments is to contain the harmful effects of kangaroos on other land management practices. Commercial killing of kangaroos is actually undermining this aim by leaving an unnaturally high female to male ratio in the population. The males are preferred because they provide more fur and meat, thus making them more profitable for commercial shooters.
In 1985, the late Peter Rawlinson, wildlife adviser to the Australian Conservation Foundation and senior lecturer in Zoology at La Trobe University, conclusively established a shooter-bias toward male kangaroos of up to 80%. This bias has since been verified by a Senate Select Committee enquiry into the kangaroo industry in 1988.
The male bias inadvertently leaves a far higher than natural percentage of females in kangaroo populations subject to commercial shooting. Consequently the potential breeding capacity of such populations is increased.
For the grazier, this raises the prospect of increasing conflict with growing numbers of kangaroos.
Over time, commercial killing actually results in an increase in the number of kangaroos and therefore the potentially harmful effects that kangaroos may have on other land management practices.
\BDescription:\b Kangaroos can provide headaches for sheep farmers \I(Webster Publishing)\i
#
"Kangaroos and the Greenhouse Effect",6,"c\9\d_0003.jpg","c","0"
One environmental factor that now threatens to drastically alter Australia's flora and fauna is the greenhouse effect.
While no-one knows exactly how and to what extent the greenhouse effect will influence Australia's climate, few doubt that we will experience major global climatic shifts in the near future.
Many different scenarios have been put forward. The common feature of all predictions relating to the greenhouse effect is the rate of climatic change.
The sudden change in climatic conditions across Australia will make the future of many native species uncertain. Even many widespread and abundant species may not be able to adapt to the changes.
These climatic changes will threaten the Red, Eastern Grey and Western Grey kangaroos. The semi-arid sheep rangelands may suffer large scale climatic change which may include a rise of 2-4 degrees Celsius in annual mean temperature within 40 years. Wildlife habitats and agricultural land-use patterns in the sheep rangelands will alter dramatically over this time.
The large kangaroo species would be affected by these changes in two ways. Firstly, kangaroos would become more obvious as they gather at roadsides to feed on the last green vegetation, resulting in calls for greater controls.
Kangaroos already respond to normal dry conditions by congregating along roads where moisture and run-off supports the last 'green pick'. This makes kangaroos more obvious during dry conditions, often leading to the perception that their numbers have increased.
Calls for increased killing frequently follow. This would be heightened in the future as kangaroo populations gradually shift in response to climatic change.
Secondly, the greenhouse effect could result in a reduction in tree cover in the rangelands from between 30-70% to less than 10%. This will make large areas of the present stronghold of kangaroos unsuitable to the Eastern Grey.
The biological resilience of kangaroo populations and the ability of the kangaroo species to adapt to sudden environmental change will be tested by the greenhouse effect.
\BDescription:\b \I(Webster Publishing)\i
#
"Kangaroo Farming and Land Degradation",7,"f\5\d_0070.jpg","c","cow0"
Supporters of the kangaroo industry have suggested that kangaroo farming would be an answer to the land degradation caused by introduced domestic livestock.
There can be no denying that much of Australia, particularly arid and semi-arid regions have suffered greatly from overgrazing by heavy, hard-hoofed introduced animals such as sheep and cattle.
Land degradation resulting from clearing, overgrazing and compaction of the soil, together with the subsequent soil erosion, has been recognised as one of Australia's major environmental problems. Land degradation not only threatens native plants and animals, but ultimately our economy as the carrying capacity and productivity of the land is reduced.
The friends of the kangaroo industry have taken advantage of the increasing public concern over land degradation, arguing that soft footed kangaroos are better suited to our sensitive soils and fragile native vegetation. Kangaroo farming has been presented as the alternative to sheep and cattle grazing in some areas, particularly in the sheep rangelands of New South Wales and Queensland.
The promoters of kangaroo farming maintain that an increase in markets and prices for kangaroo products would provide the necessary incentive for traditional sheep and cattle graziers to 'switch' to kangaroos.
This argument is appealing to those who would like to see introduced animals removed from the arid and semi-arid zones. Even some conservationists, usually concerned about wildlife exploitation, seem prepared to sacrifice the wild status of the kangaroo in the belief that kangaroo farming is a better option to continued land degradation.
Despite these claims of benefits, commercial and social considerations show that kangaroo farming is not a viable alternative to sheep and cattle.
\BDescription:\b \I(Webster Publishing)\i
#
"Kangaroos and Regeneration",8,"a\8\d_0056.jpg","c","0"
In almost every case where there is a call to kill kangaroos, there are alternatives. Even at Hattah-Kulkyne National Park in Victoria, where over 10,500 kangaroos were killed in 1991-92 as part of a revegetation program, there were alternatives to the 'quick-fix' approach of killing.
In fact, killing large numbers of kangaroos in an attempt to promote natural regeneration has resulted in some serious environmental problems such as weed infestation resulting from the removal of a major herbivore, and pollution from the carcasses contaminating water ways.
Managers of the Hattah-Kulkyne Park are now discovering that only by actively replanting the trees that were cleared over a century ago will they restore the balance of the degraded park. This could have been done without the slaughter of kangaroos, particularly with the assistance of seedling protectors.
\BDescription:\b \I(Webster Publishing)\i
#
"Kangaroos and Crop Damage",9,"g\10\d_0050.jpg","c","0"
In those areas where kangaroos and wallabies do present a problem to crops, more and more farmers are discovering the long term merits of artificial tree guards, electric fences and even sonic devices.
The 'Roo-Guard', for example, emits a high frequency sound within the kangaroo hearing range. Moving towards the sound causes the kangaroo discomfort. The 'Roo-Guard' is proving to be very effective in protecting crops and pasture.
The one-off costs of electric fencing or ultra-sonic fencing compares well with conventional fencing costs and is an investment quickly paid for by increased productivity.
\BDescription:\b \I(Webster Publishing)\i
#
"The Answer to Land Degradation",10,"g\10\d_0086.jpg","c","0"
Most kangaroos entering the commercial market originate from Australia's sheep rangelands. Although covering some 70% of Australia, these areas are insignificant in terms of crop production and account for less than 15% of Australia's meat production.
The marginal nature of these areas means that kangaroos, even if in large numbers, can only be placed very low on a long list of environmental and economic factors affecting land holders profits. Killing kangaroos does nothing for the long term viability of many properties.
Areas with poor soil, low rainfall and/or sensitive vegetation should never have been turned over to stock at all. The continuation of many leases, some of which are as large as Sydney or Melbourne, must be questioned.
In the past, farmers have been encouraged to heavily stock their properties in order to generate greater profits. Early leases actually demanded stocking rates which we now know were too high even in those areas that can support grazing.
Early misguided notions of what could be expected of this land led to the 'boom or bust' style of management which now typifies the arid and semi-arid regions of Australia. During good times, land managers tend to increase stocking rates to the maximum capacity of the land.
As the carrying capacity varies according to the season and Australia's notorious frequency of drought, the income of graziers who practice high stocking rates also fluctuates greatly. In good years, they may do very well.
\BDescription:\b \I(Webster Publishing)\i
#
"The Answer to Land Degradation - (2)",11,"g\10\dfat23.jpg","c","0"
When the inevitable drought strikes however, landowners find themselves overstocked, and with everyone trying to sell at the same time, market prices fall. Stock is kept on for as long as possible in the hope of a break in drought conditions or an increase in market prices. If the drought persists, stock condition and therefore market prices continue to fall.
It is this process that has resulted in compaction of the soil, reducing its capacity for plant (grass) growth which in turn leads to erosion and ultimately reduces the land's carrying capacity. Over a long period of time the process of land degradation is self promotive.
Today, some farmers are resisting the temptation to overstock during good times. While their income may not be as great during times of plenty, their land remains in better condition when inevitably drought strikes. The stock they do have remain in good condition and fetch food prices for longer than animals from overstocked properties.
Those farmers who have reduced stocking rates not only address the issue of soil compaction and erosion, but also secure a more consistent (and often greater) income in the long term. It is not necessary to resort to the exploitation of our wildlife with this enlightened approach to land management.
\BDescription:\b \I(DFAT)\i
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7#
10,0
"Population Growth and Change",1,"g\10\2_0056.jpg","c","0"
Australia has a developed economy which relies heavily on primary production from natural resources. The causal connections between current patterns of economic activity and environmental degradation are more direct than is the relationship between the environment and population growth per se. However, population levels affect the overall scale of activities that in turn impact on the environment.
There are many interacting factors involved in the relationship between population and the environment, such as the characteristics of the population, consumption per person, production of waste per person and the interaction between resource use and environmental impact.
Interaction between resource use and environmental impact is of particular concern with regard to increased water usage and water quality. Further, urban expansion competes with agriculture and the natural value of land use. Air pollution, congestion and inefficient energy use are other concerns about the present urban way of life.
Change in population for a given area is due to natural population increase (the net effect of births and deaths) and net migration.
Natural increase has remained positive since 1947 and is projected to remain positive for the foreseeable future. Net migration has a direct influence on population growth and structure. It also contributes indirectly as migrants and their children subsequently contribute to natural increase.
Fluctuations in net migration, primarily determined by the level of immigration, have been responsible for the more marked changes in Australia's population growth.
\BDescription:\b Noxious weeds in a river \I(DFAT)\i
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"Settlement Patterns",2,"map42","c","0"
Australia's population is concentrated in the east, south-east and south-western coastal zones. In 1996 some 86% of the population lived on the coastal fringes.
Australia is one of the most urbanised countries in the world. The United Nations has estimated that the level of urbanisation for developed countries is 73%. For Australia, the level of urbanisation is estimated to be 86%, with 66% living in the nation's fourteen major urban areas, that is cities with a population greater than 100,000.
Historically there has been a consistent increase in the number of city residents until 1976 when 86% of people lived in urban areas of more than 1,000 inhabitants. Since then there has been a small reversal of this trend.
\BDiagram:\b The proportion of the population in capital cities.
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"Urban Growth",3,"a\4\4_0059.jpg","c","0"
While over the last two decades there seems to have been a slight move away from the process of urbanisation, this appears to have occurred outside the capital cities.
Urban growth has been influenced by immigration as immigrants tend to settle (at least initially) in urban areas, thus reinforcing the pattern of urban concentration. This is offset to some extent by the pattern of movement of older residents away from the major cities to smaller coastal centres.
In recent years much of the growth of Sydney and Melbourne has been due to immigration. Approximately 80% of immigrants are estimated to settle in Australia's five largest cities.
\BDescription:\b Melbourne's population growth has partly been due to immigration \I(DFAT)\i
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"Impacts of Tourism",4,"g\10\6_0080.jpg","c","beach0"
Tourists have a particular impact on areas of scenic beauty and national parks which are of high biological conservation value.
Tourism in Australia is increasing. In 1995 there were 5.7 million overseas short-term visitors, compared to 2.3 million in 1991, adding to the consumption demand.
\BDescription:\b Tourists in Australia \I(DFAT)\i.
Manufacturing has a place at the centre of economic and scientific development. It plays a decisive role in determining the rhythms of growth, international trade and technological progress. Its interrelationship with the environment includes the inputs of resources and energy and the outputs of pollution emissions.
The location of manufacturing industry also has environmental implications in terms of the transport, infrastructure and housing needs of its employees.
\BDescription:\b Manufacturing plant \I(DFAT)\i
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"Construction of Shelter and Infrastructure",6,"g\9\tony17.jpg","c","handsaw0"
The economic costs of expanding urban areas have caused strain on the provision and funding of urban infrastructure. It has been claimed that there is an 'infrastructure crisis' with inadequate provision of roads, sewerage, electricity, and social infrastructure such as school buildings, medical centres and police stations.
The stock of shelter and infrastructure is affected by construction, demolition, conversion, restoration, as well as the destruction that results from natural disasters.
The construction of residential buildings adds to the stock of dwellings or adds to the quality of existing dwelling units.
Non-residential construction includes non-residential building and engineering construction. Non-residential building provides facilities such as shops, offices and schools.
Engineering construction provides infrastructure such as roads, bridges, railways, harbours, water storage and supply, sewerage and drainage, electricity generation, pipelines and telecommunications.
\BDescription:\b Construction site \I(Webster Publishing)\i
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"Supply of Water",7,"f\3\1_0012.jpg","c","0"
Water and energy are the basic utilities without which there would be no human settlement. Access to these utilities largely determines the quality of particular human settlements.
Water for human settlements is used for drinking, washing, production, recreation, gardens and as a sink for pollutants and wastes. The availability and quality of water is important for health and is a major determinant of the quality of human settlements.
Water supply does not appear to be a problem for major settlements in the short term, although Adelaide and Perth appear to have few alternative sources available. In the longer term, additional dams would be required.
Based on current rates of consumption per person, a major new water catchment for Sydney would be required on the Shoalhaven River early next century.
Melbourne will need to harness inland rivers such as the Big River, thereby competing with agricultural use of water. The supply of water to Australia's major cities may also conflict with natural uses of water.
Sewerage pollution and storm water run-off have become a problem, particularly in Sydney's Nepean-Hawkesbury river catchment. This will require more intensive treatment of waste water and increased treatment costs.
\BDescription:\b Lake Waggboonyah Dam \I(DFAT)\i
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"Transport and Noise",8,spread270.spr.jpg,c,0
An effective transport system is essential to enable the factors of production, people and material to coordinate and assemble within urban areas.
Transport systems alter the physical patterns of settlements, and the accessibility of infrastructure and services. They provide the means for the flow of goods necessary for the support of the settlement. They also have the adverse impacts of pollution, congestion and traffic accidents.
Traffic congestion leads to increased air pollution and reduced quality of life. Another adverse impact of transport is noise. All modes of motorised traffic generate noise.
Some examples of traffic modes and the noise generated are provided in this table.
\BNote to table:\b
\IdB(A) is an index used to assess the impact of noise.\i
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"Use of Public Transport",9,3_0063.jpg,c,0
Public transport provides a more efficient transport system than private motor vehicles in terms of energy and other resources. Patronage provides a measure of both the availability and quality or convenience of the service.
A survey conducted in Adelaide found that the proportion of people who travelled to work or place of education by public transport had declined marginally over the last decade or so.
The two main reasons employed people gave for not travelling by public transport were inconvenience (32.8%) or their vehicle was used for work purposes (20.1%).
\BDescription:\b The Sydney Harbour Jetcat is a good form of public transport \I(DFAT)\i
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"Clean Up Australia Day",10,"g\10\2_0040.jpg","c","0"
On Clean Up Australia Day, 2 March 1997, approximately half a million Australians collected thousands of tonnes of rubbish from roadsides, rivers, parklands, beaches and waterways around the country.
It all started from an idea by Ian Kiernan, 1994 Australian of the Year, to make a better environment by encouraging people everywhere to clean up their local area.
After sailing single-handed around the world in 1986, Ian Kiernan returned to Australia and organised Clean Up Sydney Harbour in 1989, when 40,000 volunteers removed 5,000 tonnes of waste from the harbour and its foreshores. Its success led to an expansion of the campaign to a Clean Up Australia Day across the country each year since 1990.
The campaign has spread beyond Australia. In 1993, an estimated 30 million people in 80 countries took part in the first Clean Up the World Day.
\BDescription:\b Clean Up Australia Day \I(DFAT)\i
Disasters come in all shapes and sizes. They can occur anywhere and they are unpredictable to a large extent - disasters can occur at any hour of the day or night. Disasters can vary from each other in the following ways:
* \ICause\i - They can be natural, or human-made (e.g. flood/transport accident);
* \IFrequency\i - Some occur more often than others (e.g. bushfire/earthquake);
* \IDuration\i - Some may be of limited duration, others may go on for quite long periods of time (e.g. bushfire/drought);
* \ISpeed of onset\i - Some happen very quickly, while with others there is a warning period of perhaps hours or days (e.g. bushfire/famine);
* \IScope of impact\i - Some disasters may affect a relatively small area, and others may affect whole countries (e.g. tornado/famine);
* \IDestructive potential\i - Varies enormously with the type of hazard (e.g. landslide/cyclone);
* \IPredictability\i - Some hazards follow certain patterns, and others do not (e.g. floods/toxic emission);
* \IControllability\i - With some disasters, humans are totally helpless and must let the disasters run their course. Sometimes humans can do something to lessen the impact of disaster, even if they cannot prevent a disaster from occurring (e.g. volcanoes/bushfires).
\BDescription:\b The affects of a drought \I(Fairfax Photo Library)\i
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"Types of Natural Disasters",2,"f\3\3_0096.jpg","c","0"
\BGeological\b
Geologically, the Australian continent is relatively stable, not subjected to volcanoes at all, nor to extreme earthquakes in populated areas, although several have caused heavy damage and even loss of life. Landslides are a minor hazard in Australia and our coastline is largely protected from the worst effects of tsunamis (huge seismic sea waves).
\BMeteorological\b
Australia suffers regularly from the effects of meteorological hazards in the form of tropical cyclones, droughts, bushfires, floods and severe storms. Disasters regularly caused by these hazards may not take a large toll in terms of lives but they bring damage that can run into hundreds of millions of dollars. Their effects may cause suffering to individuals and families that can last for years.
\BDescription:\b Stranded sheep in "Birrah" in north-west NSW \I(DFAT)\i
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"Bushfires",3,"g\10\3_0095.jpg","c","0"
Australia has a large number of what we call bushfires, caused either by lightning or by humans. Not all are disasters however, and small fire, if not quickly detected and put out, can get out of control and a disaster may occur. In drier seasons the danger is much higher, and all too quickly bushfires can spread to threaten human life, homes, crops, livestock, forests and wildlife.
\BBushfire disasters\b
Bushfires are one of the most destructive forces of nature. Firefighters, both professional and volunteer, risk their lives each year to control and eventually extinguish them.
Thankfully, few bushfires earn the title of 'disaster' but in Tasmania, South Australia, Victoria, and New South Wales, repeated disastrous bushfires have occurred, in which many people have lost their lives, or their homes and property. Bushfires in Australia occur as either 'grass fires' or 'forest fires'.
\BDescription:\b Adelaide after a bushfire \I(DFAT).\i
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"Types of Bushfires",4,"g\10\3_0090.jpg","c","0"
\IGrass fires\i - These occur mainly on grazing or farming land and although they often destroy fences, livestock and some buildings, they rarely result in loss of human life.
\IForest fires\i - Under adverse weather conditions, fires in Australian eucalyptus forests cannot be stopped and often destroy homes which border such areas. Huge amounts of flammable eucalyptus vapour, transpired from leaves, create fireballs which often engulf the forest upper storey ahead of the main fire front.
Clouds of dense smoke can mask the fire front from both ground and aerial observation. During the Ash Wednesday fires in 1983, aerial-mounted, infra-red heat-sensing equipment was needed to locate and plot some fire fronts.
South eastern Australia has the greatest wildfire hazard in the world. Bushfires are driven south by strong, hot, northerly winds and long fire flanks frequently become fire fronts when southerly wind changes occur.
Timely, accurate weather information is vital for firefighting teams. Bushfires burn until stopped by nature which may be many weeks after ignition.
\BDescription:\b \I(DFAT)\i
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"Bushfire Disaster - An Example",5,"g\10\3_0092.jpg","c","0"
\BConditions for disaster\b - February 16th 1983, Melbourne was experiencing a very hot, dry day. The temperature peaked at 43░C with relative humidity of only 6%. Drought conditions had persisted in south eastern Australia for several years with the 1982/83 summer being extremely hot and dry.
Many small to moderate bushfires occurred in South Australia and Victoria over this period. Fires burnt over 100,000 hectares near the New South Wales/Victoria border on February 1st.
On February 6th, 95 fires were reported as they flared in hot north westerly winds. By February 16th, 'Ash Wednesday', South Australia and Victoria were tinder dry.
\BThe toll\b - In the 24 hours following that morning, a holocaust of bushfires erupted, burning over 350,000 hectares across the two States. A total of 2,000 families lost their homes while 75 people died.
Hundreds of injured people were treated at hospitals. Livestock losses were very high with 340,000 sheep and 18,000 cattle either dead or having to be destroyed.
\BDescription:\b The after-effects of a bushfire \I(DFAT)\i
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"Floods",6,"g\9\3_0093.jpg","c","0"
People who live near rivers, or in low-lying coastal areas, live with the threat of floods. Periods of heavy rain, not necessarily in their area, can lead to rises in the water level of streams and rivers, often to where their channels can no longer hold the volume of water. There are several types of flooding:
\BSlow-onset floods\b - Flooding of rivers in areas of central and western NSW and Queensland, as well as parts of Western Australia, may last for one or more weeks, even months on some occasions. Floods in these areas can lead to major losses of stock and damage to crops as well as extensive damage to road and rail links.
\BRapid-onset floods\b - Flooding can occur more quickly in the mountain headwater areas of these larger rivers as well as in the rivers draining to the coast. The rivers here are steeper and drain more quickly, with flooding often only lasting for one or two days. These floods can be potentially much more damaging and can pose a greater risk to loss of life and property since there is generally much less time to take preventative action.
\BFlash floods\b - Flash flooding results from relatively short, intense bursts of rainfall, often from thunderstorms, and can occur in almost all parts of Australia. This type of flooding poses the greatest threat to loss of life and can result in significant damage to property and major social disruption. Flash floods are a serious problem in urban areas where drainage systems are unable to cope.
The following are the most common terms associated with flooding and their meanings:
\BMinor flooding\b - This causes inconvenience, and closing of minor roads and low level bridges.
\BModerate flooding\b - Low-lying areas are inundated, requiring removal of stock, equipment and evacuation of isolated homes. Main traffic bridges may be covered.
\BMajor flooding\b - Higher areas are inundated, with towns and properties isolated. Extensive damage is caused.
\BLocal flooding\b - Intense rainfall could cause a high runoff in some areas, but would not usually lead to significant rises in the main streams.
\BSignificant river rises\b - This warning is issued if it is not certain that the initial flood levels will be exceeded in the main streams. It lets people know that appreciable rises are expected.
\BDescription:\b Flooding at Tamworth \I(DFAT)\i
#
"Flooding Disaster Example - Brisbane 1974",8,jlaws.jpg,g,0
\BThe weather systems\b - The wet season in northern Australia is the result of a monsoonal air flow usually restricted to the far northern parts of the continent. During January 1974 however, this moist mass of tropical air moved steadily southward with resultant substantial rainfall over much of Queensland.
The main 'trigger' for the Brisbane floods was Cyclone \IWanda\i which crossed the Queensland coast on January 24th about 150 kilometres north of Brisbane. It only caused minor wind damage but added heavy rainfall to an already saturated river catchment. Furthermore, it triggered the monsoonal air mass over southern Queensland into periods of intensive rain over a five day period. Among the highest recordings were 1,318mm (almost 1.5 metres) whilst in Brisbane itself 819 mm of rain fell.
\BFlooding\b - By January 26th flooding was reported in the upper Brisbane Valley with the nearby city of Ipswich experiencing major flood levels. In Brisbane, periods of intense rainfall flooded small creeks, drains and floodways. These local floods, when added to the rising Brisbane River, produced the highest flood levels to date this century.
\BDamage\b - 13,000 buildings were affected with 56 homes being swept away and 1,600 partially submerged. Insurance claims totalled about $70 million (1974 value), but this figure mainly reflected 'rain damage' as flood insurance is not generally available. The true figure was probably up to three times greater! Road and bridge repairs were put at $25 million (1974 value). Ships, including a large oil tanker, were torn from their moorings.
#
"Costs and Effects of Storms",9,7_0013.jpg,c,thunder0
At any time of the year severe thunderstorms can occur throughout Australia. The majority strike between September and March when the supply of solar energy is greatest, but severe winter storms are common in Western Australia.
The frequency of land gales in Australia is difficult to specify, but generally, in the southern half of the country, extreme winds tend to occur in winter and spring. In the tropical north, extreme winds usually hit in summer and autumn, and are often due to tropical cyclones.
Analysis of geographical distribution of severe thunderstorms in Australia is hampered by low population density and lack of observations over most of the continent. Existing records suggest that most damaging storms occur in a crescent from Brisbane, through coastal NSW and Victoria, to Adelaide, but it is likely that many severe thunderstorms strike less populated areas without being observed or recorded.
The most damaging individual storms have hit south-eastern Queensland and the central NSW coast, south to Sydney. These have included tornadoes on numerous occasions.
\BDangers to people\b - On average, three people are killed by lightning each year. Deaths and injuries also occur when small boats are hit by thunderstorm squalls, when trees or their limbs fall, or from flying debris in strong winds. As mentioned, tornadoes also cause deaths.
\BAnnual damage bill\b - From 1967 to 1997 severe storms cost billions of dollars in insurance payouts in Australia. The true cost of all types of severe storms probably averages well over $500 million each year (including damage estimates of uninsured property).
\BDescription:\b Thunderstorm forming off the Darwin coast \I(Peter Jarver)\i
#
"Thunderstorm Disaster - An Example",10,"b\2\7_0013.jpg","c","thunder0"
21 January 1991: A thunderstorm with winds estimated 250 km/h, large hail and torrential rain tears through the north area of Sydney, injuring over 30 people and causing more than $200 million in damage. Two days later a tornado and hailstorm cause over $25 million damage in Adelaide - the worst natural disaster since the Ash Wednesday bushfires.
\BDescription:\b A thunderstorm \I(Peter Jarver)\i
#
"Australian Tropical Cyclones",11,"0","g","wind0"
Tropical cyclones (known as hurricanes or typhoons in some countries) are like giant whirlwinds in which air moves in a large, tightening spiral around a centre of extreme low pressure.
The cyclone season in Australia is from about November to April, and cyclones mainly affect coastal areas north of Perth, WA through Darwin, NT, across and down through QLD and occasionally as far south as the northern NSW coast. The area of greatest risk lies north of the Tropic of Capricorn.
\BFrequency\b - Cyclones occur frequently in the southern hemisphere, with an average of ten per year being tracked by the Bureau of Meteorology in the Australian region alone. Of these, six may be expected to cross the Australian coast each year. Cyclones further out in the Indian and Pacific Oceans are monitored in case they threaten Australian islands or nearby countries.
\BEffects\b - Cyclones approach from the sea bringing with them torrential rains, extreme winds and sometimes storm surges. Damage caused by each cyclone varies widely depending on its path. Most deaths from cyclones occur either from drownings, collapsed buildings, or debris which become lethal projectiles carried along by the wind.
One other effect of a cyclone is that it can produce a storm surge (or storm tide). A storm surge may be caused by cyclonic winds blowing across the water and a fall in atmospheric pressure. The lower pressure at the eye of the cyclone actually raises the level of the sea in and close to the centre.
As a cyclone nears the coast, low-lying areas may suffer flooding because strong on-shore winds have displaced the storm surge ahead of the cyclone's centre. The amount of flooding that occurs depends very much on the state of the tide when the cyclone crosses the coast. If the tide is fairly low, flooding may not occur.
#
"Cyclone Disaster Example - Cyclone Tracy 1974",12,"0","The devastating affects of Cyclone Tracy","cyclone2.avi"
\BDarwin, NT - Tropical Cyclone Tracy, December 1974.\b
The following is an account of some significant events in the life of tropical Cyclone \ITracy.\i
December 20 - A low pressure system identified in the Arafura Sea.
December 21, 9.30am - A cyclone warning issued and the name \ITracy\i given.
December 22, 3.30pm - Radar in Darwin clearly identifies the eye about 200 kilometres north of the city.
December 23, 9.00am - Heavy rain and wind reported along coast north of Darwin. 11.00 pm - Cyclone begins to move steadily southward.
December 24, Noon - Cyclone confirmed as moving toward Darwin. 12.30pm - Cyclone warning issued to Darwin residents advising that \ITracy\i should cross coast early on Christmas Day.
December 25, 1.00am - Destructive winds reported throughout Darwin.
3.00am - Wind gusts of greater than 200 kilometres per hour recorded along with torrential rain.
3.10am - Wind recorder fails at 217 kilometres per hour.
4.00am - Cyclone's eye directly overhead and calm is felt for about 30 minutes.
4.30am - Extreme winds resume but this time from the opposite direction.
Deaths and damage - \ITracy\i claimed 49 lives in Darwin while a further 16 were lost at sea on several small vessels which were in the path of the cyclone. Approximately 650 people were treated for injuries on Christmas Day, while more than 35,000 people were evacuated in the days that followed.
Evacuation was necessary because few essential services remained, potential for disease was great and there were only a few of Darwin's 12,000 homes remaining even reasonably intact. Total property damage exceeded $1.3 billion in 1992 values.
\BDescription:\b The devastation caused by Cyclone \ITracy\i \I(Fairfax Photo Library)\i
#
"Earthquakes",14,"f\10\3smh.jpg","c","0"
Earthquakes are a shaking or trembling of the earth's crust, caused by underground volcanic forces or breaking and shifting of rock beneath the surface as huge stresses are released. Small earthquakes may sometimes be caused by human activity (e.g. filling of large reservoirs).
\BCharacteristics and measurement\b
\BVariability\b - Earthquakes are unpredictable and strike without warning. They range in strength from slight tremors to great shocks lasting from a few seconds to as long as five minutes. They could come in a series over a period of several days.
\BMagnitude\b - Energy released by (or magnitude of) an earthquake is expressed on a recording device, using the Richter Scale. This Scale is open-ended, as there is no upper limit to the amount of energy an earthquake might release. The most severe earthquakes so far have not exceeded 9.5 on this scale. It is not a simple arithmetic scale. For instance, energy released in a magnitude 7.0 quake is about 30 times greater than in a 6.0, which is 30 times greater than a 5.0 and so on.
\BIntensity\b - Another scale used to describe earthquakes is the Modified Mercalli (MM for short). It rates the amount of damage caused (or intensity) and uses Roman numerals at each level. On this scale I = a barely detectable tremor, and XII = total damage.
\BDescription:\b The ruins in Newcastle after the 1989 earthquake \I(Fairfax Photo Library)\i
#
"Causes of Injury and Damage by Earthquakes",15,"g\10\4smh.jpg","c","0"
Most casualties in earthquakes result from falling objects and debris because shocks may damage or demolish buildings and other structures. Electricity and telephone lines, gas, sewer and water mains can be damaged; landslides, ground displacement (faulting), subsidence and even tsunamis (huge ocean waves) may be triggered; and many people left dead, injured or homeless.
Because of Australia's geological position, we are prone to what seismologists call 'intra-plate' earthquakes. These are different and poorly understood in comparison with the more familiar 'plate-margin' type, common in areas like California, USA.
The historical record in Australia goes back only about 200 years. The first reported earthquake lasted about three seconds at Port Jackson, NSW in June, 1788. In 1837, early settlers in South Australia experienced an earthquake for 20 seconds. Similarly in the early histories of Hobart (1827), Melbourne (1841) and Perth (1849), earthquakes were felt.
In the last 75 years there have been 17 earthquakes in Australia registering six or more on the Richter Scale. This is a rate of about one every five years, compared to a world average of about 140 per year. Although the larger Australian earthquakes caused significant damage, they are, on the whole, of smaller strength than the world's most damaging shocks.
Until Newcastle's December 1989 event, the damage bill attributed to earthquakes in Australia, during the previous 200 years, had been comparatively low.
"Example of An Earthquake - Newcastle 1989",17,"g\10\5smh.jpg","c","0"
\BNewcastle, NSW\b
At 10.27am on 28 December 1989, Newcastle, Australia's sixth most populated city, was devastated by a moderate earthquake measuring 5.6 on the Richter Scale. The Newcastle earthquake, the first fatal one in Australia, claimed 12 lives.
The devastation to buildings and other structures was extensive - unusual for a relatively small magnitude earthquake. This was due mainly to an underlying, thin layer of alluvium which appeared to magnify ground motion (shaking). The epicentre was located 15 km WSW of the city centre, near Boolaroo.
\IEnd of a myth\i - Despite Australia's seemingly low risk situation in the middle of one of earth's larger tectonic plates, we have been subject to many earthquakes larger than that of Newcastle. The Australian Seismological Centre in \JCanberra\j estimates that on average, the Australian region experiences an earthquake of this size, or larger, about every ten months.
Most of these, however, have been in areas of low population density (e.g. \JTennant Creek\j 1988, magnitude 6.3, 6.4 and 6.8). For many years, a view was held by most Australians that we could not be subjected to this form of natural disaster. The Newcastle experience dispelled this myth!
\IDeaths, injuries and damage\i - There were 12 deaths and 106 injuries, very few considering 35,000 homes and 3,000 other buildings were moderately to seriously damaged in Newcastle. Older buildings suffered the most.
At the Kent Hotel in Beaumont Street, Hamilton, three fatalities occurred. The other nine resulted from partial collapse of the Newcastle Workers Club, the inner city's largest. Three floors collapsed during the earthquake, trapping many people.
The timing, however, mid-morning in the Christmas holidays, may have saved many more. A pop concert, which could have attracted up to 2,000 people, was scheduled for that night in the Club.
Over 100,000 students and teachers attend educational institutions in the Hunter Valley. There were 45 schools damaged in the region, some so badly as to require demolition. If this event had struck during school-term, deaths and injuries could have been many times worse.
\IDamage cost\i - Estimated total damage to Newcastle was $1.5 billion (1990 values).
\BDescription:\b Newcastle 1989 after the earthquake \I(Fairfax Photo Library)\i
#
"Droughts in Australia",19,7_0011.jpg,c,0
Because of Australia's geography and climate, drought is a constant threat. Severe water shortages, due to failure of 'usual' rains, occur quite frequently in many areas of Australia. Drought affects whole communities - farmers and city dwellers alike, but in different ways.
Extreme drought can result in huge loss of life and resources, as occurred in the Sahel Zone of Africa in 1973-74. Australia has not experienced a drought on this scale, but the potential exists.
\BDescription:\b Droughts can cause cattle to perish \I(Peter Jarver)\i
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!,!,!,!,!
9#
15,0
"What is the Atmosphere?",1,"g\10\7_0061.jpg","c","thunder0"
Before we can understand anything about the greenhouse effect, we need to know about the atmosphere and the role it plays in this important environmental issue.
The atmosphere is a gaseous mixture surrounding the surface of the earth. It is divided into two general regions - the homosphere and the heterosphere, as shown in this figure. The homosphere includes the area to about 90 kilometres outwards from the earth. The heterosphere is above the homosphere.
The majority of the mass of the atmosphere lies in the homosphere. The lowest portion in the homosphere is called the troposphere. Within the troposphere, the temperature becomes colder the further you move away from the earth's surface. The boundaries of the troposphere change according to latitude and the season of the year.
Above the troposphere, the air temperature stabilises and forms a stratified cover. This layer is named the stratosphere. The ozone layer is formed in the stratosphere.
The troposphere and stratosphere are the two important layers of the atmosphere upon which most environmental concerns are focused.
\BDescription:\b Cloud build up around Howard Swamp near \JAlice Springs\j \I(Peter Jarver)\i
#
"Enhanced Greenhouse Effect",2,7_0086.jpg,c,0
Nitrogen and oxygen ù the main components of the earthÆs atmosphere ù are almost completely transparent to the sunÆs rays. The clouds, the oceans, land, snow and ice reflect about one-third of the incoming solar (short-wave) radiation. The earth absorbs the remaining two-thirds of the solar energy, mainly in the tropics, from where large-scale circulations in the oceans and the atmosphere redistribute it. Ultimately, it is re-radiated back to space as infra-red (long-wave) radiation, thus maintaining a balance with the absorbed solar radiation.
Water vapour, carbon dioxide and other trace gases absorb infra-red radiation emitted by the earthÆs surface and, as a result, have a major impact on this radiation balance. The absorbed radiation is not retained but re-emitted in all directions, thus increasing the temperature of the earthÆs surface. This warming effect, long recognised as a major element of the climate system, is known as the greenhouse effect. Without clouds, water vapour and these other so-called greenhouse gases (but with no change in the amount of solar radiation reflected back to space), the global surface temperature would average û18░C rather than the present 15û16░C.
We now know that human activity has led, and is still leading, to increased atmospheric concentrations of existing greenhouse gases (carbon dioxide, methane, nitrous oxide and ozone), as well as to the presence of new greenhouse gases such as CFCs. Most of these gases, once released into the atmosphere, persist for tens to hundreds of years, with an associated long-term impact on the background atmospheric levels. Using an understanding of the processes that govern the climate system, and applying this knowledge in computer climate models, scientists consider that the presence of additional greenhouse gases will affect the radiation balance of the atmosphere and lead to a warming at the earthÆs surface. This is now generally referred to as the enhanced greenhouse effect.
The actual impact on global climate is likely to be complex and involve changes in atmospheric and oceanic circulations, accompanied by possible changes in sea level, diurnal temperatures, rainfall and other climatic variables. While climate model simulations already offer predictions of the global impact of the enhanced greenhouse effect, only broad indications of potential change on a regional scale are currently available.
A further complicating factor has emerged in recent years. This is the realisation that, in addition to raising greenhouse gas levels, human activity is also leading to an increase of aerosols in the lower atmosphere. The most significant are sulphate aerosols that come from sulphur dioxide emissions from power generation and ore processing. Carbon-based aerosols produced by burning biomass are also important. Aerosols can reflect sunlight as well as change the amount, type and radiative behaviour of clouds, resulting in a lowering of surface temperatures. Due to their short lifetime (days/weeks), their cooling effects are temporary and regional, but for some regions, particularly in the northern hemisphere, the cooling is estimated to be about the same as the warming effects of carbon dioxide.
Since the 1990 Intergovernmental Panel on Climate Change (IPCC) First Assessment Report, considerable progress has been made to distinguish between natural and anthropogenic influences on climate. In its Second Assessment Report (IPCC, 1995) the IPCC concludes that despite uncertainties in key factors, æthe balance of evidence suggests that there is a discernible human influence on global climateÆ.
IPCC (1995) projects an increase in global mean surface temperature relative to 1990 of about 2░C by 2100 and a corresponding increase in sea level of about 50 cm.
\BDescription:\b The Train Hills \I(Peter Jarver)\i
#
"Ozone Depletion",3,"g\10\2_0073.jpg","c","0"
About 15 to 50 km above the earthÆs surface is the part of the atmosphere called the stratosphere. In the stratosphere ù unlike the lower atmosphere (the troposphere) ù temperatures increase with height. As a result, it is more stable and does not have the same amount of vertical mixing of air as the troposphere. From the point of view of life on earth, the most important fact about the stratosphere is its concentration of ozone which, although low, is much higher than that in the troposphere.
Ozone is produced when short-wavelength ultraviolet (UV) radiation from the sun acts upon oxygen molecules. Once formed, ozone absorbs UV. But ozone is an unstable molecule, and for every molecule formed in the stratosphere, another breaks down. Thus, the ozone layer is the result of natural processes that both produce and destroy the gas, and its concentration depends on the balance between these processes.
Chlorine, bromine and oxides of nitrogen, in their reactive forms, can catalyse the breakdown of ozone in the stratosphere. They are part of the natural ozone destruction cycle. Human activities ù domestic, industrial and agricultural ù produce emissions that increase the concentration of these chemicals and accelerate the destruction of ozone.
This destruction by anthropogenic chemicals is particularly efficient over Antarctica in spring, as a result of the presence of ozone-depleting substances in the stratosphere combined with the unique temperature, structure and circulation of the Antarctic stratosphere during the long polar night. The seasonal reduction in ozone is referred to as the ozone æholeÆ, which is a shorthand description signifying that over a large area, the stratospheric ozone concentration has fallen below normal. The ozone is replenished at the end of spring, when ozone-rich air from the rest of the stratosphere moves over Antarctica and brings ozone levels almost back to normal.
It is important to note that ozone decline is not just a polar phenomenon ù all regions apart from the tropics have shown a decline in stratospheric ozone over the last decade, although not as severe as that over the poles.
Ozone in the stratosphere reduces the amount of damaging UV radiation that reaches the earthÆs surface. Without the æozone layerÆ, life on land would be exposed to such dangerous levels of UV radiation that few life forms would survive. It is because of the ozone layerÆs essential protective role that any reduction in its concentration gives rise to such serious concern. In general, a fall of one per cent in atmospheric ozone has been calculated to be equivalent to an increase of between one and two per cent in UV radiation at ground level. In humans, exposure to UV can cause sunburn, eye damage, skin cancer and damage to the immune system in susceptible individuals. Fair-skinned people are most at risk. Many other organisms, including plants, are also at risk from increased UV radiation. Too much ultraviolet irradiation reduces plant growth, the sensitivity varying between different species. Whereas humans can avoid exposure, it is more difficult for flora and fauna to do so, although some species can protect themselves by producing UV-absorbing pigments in greater quantities following exposure.
While the existence of stratospheric ozone is so important, increases in ozone in the lower atmosphere (the troposphere) are of concern. Tropospheric ozone has a limited atmospheric lifetime and is not transported to the stratosphere to any significant degree.
\BDescription:\b Gases released by industry may contribute to the depletion of the ozone layer \I(DFAT)\i
#
"Greenhouse Emissions",4,2_0031.jpg,c,sail10
Many substances are emitted into the atmosphere from human activities and from natural sources. Outdoors, the main gases and particulates that are emitted, and that have particular environmental impacts, are:
ò carbon dioxide;
ò carbon monoxide;
ò halocarbons, such as halons (used in fire protection), chlorofluorocarbons (of various chemical formulae and known collectively as CFCs) and their replacement products such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs);
ò lead;
ò methane;
ò oxides of nitrogen including nitrogen dioxide, nitric oxide and the greenhouse gas nitrous oxide;
ò particles of various compositions and sizes;
ò sulphur dioxide;
ò volatile organic compounds (VOCs) other than methane.
Emitted gases and aerosols (suspensions of droplets or particles in the air) may contribute towards the greenhouse effect, the depletion of the stratospheric ozone layer, the phenomenon of acid deposition, the generation of photochemical smog and, on a local scale, the contamination of air, which then becomes less healthy for humans to breathe.
In some cases, the same gases may contribute in different ways to a range of effects. For example, although small concentrations of ozone in photochemical smog in the lower atmosphere are damaging to most living things, small concentrations of ozone in the upper atmosphere all around the globe are necessary for life on earth because that ozone shields the surface from harmful ultraviolet (UV) radiation.
Indoor air is mainly contaminated by emissions generated indoors rather than emissions from outdoors.
\BDescription:\b Wetlands produce methane gas \I(DFAT)\i
#
"Sources of Greenhouse Emissions",5,7_0093.jpg,c,0
The burning of carbon-containing fossil fuels powers most of AustraliaÆs transport and electricity generation and is responsible for a large part of our atmospheric emissions. Many domestic, commercial and industrial processes also emit waste gases. CFCs and halons can æescapeÆ into the atmosphere by leakage or by the destruction of manufactured items containing them. Agriculture can also be responsible for emissions and for changes to vegetation cover.
Aspects of AustraliaÆs society (such as its economy, demography and the lifestyle of its people) underlie pressures on the atmosphere. The country has abundant fossil-fuel energy resources, especially coal and natural gas, and is a major energy exporter. The scale of the energy industry is such that it creates considerable pressures on the atmosphere. The main sources of fossil-fuel-derived emissions are thermal power generation, road transport and the use of energy in industrial processes.
Coal is used to generate most electric power. The process produces ash particles, acid gases such as oxides of nitrogen and sulphur dioxide, as well as carbon dioxide, which contributes to the greenhouse effect. In Australia the amount of sulphur dioxide emitted per unit of energy generated is low by world standards because our coal generally has a relatively low sulphur content. We have a further advantage in that most large power-generating plants are located outside our main cities.
The demand for power is affected by our increasing population, economic growth and, among other factors, the energy-intensive nature of certain major industries such as aluminium production. At present, we have few economically viable alternatives to fossil fuels as our primary energy source. There is no nuclear power generation in Australia, and only a limited capacity for hydro-electricity in certain areas, such as Tasmania and southern New South Wales.
As well as coal, Australia contains rich mineral deposits of iron ore, bauxite, silver, lead, zinc and gold. The country has well-developed minerals, manufacturing and agricultural industries, and a large services sector. Much of its industry is export-orientated ù especially the mining and mineral processing sectors, which are important to the national economy. However, the treatment of mineral ores can be a major source of emissions ù often of sulphur dioxide, but also of other gases, depending on the ore and the type of treatment. Mining and ore-processing are concentrated in small areas, often wherever a suitable ore deposit may be, and these operations are generally remote from major population centres.
In urban areas, motor vehicles are the main source of emissions and therefore the main contributors to outdoor air pollution. The design of Australian cities has promoted a high rate of motor vehicle ownership and use. (Our cities have low population densities compared with urban areas elsewhere and are often described as æsprawlingÆ.)
Motor vehicle exhaust contains nitrogen, carbon monoxide and volatile organic compounds (VOCs). Together these are responsible for many local air pollution problems. Lead particles from leaded fuel are also present, although the use of such fuel is now declining. Particulate emissions come especially from diesel vehicles, but we have proportionately fewer of these than other countries.
The day-time brown haze that sometimes forms over our major cities is caused by particles and nitrogen from exhaust fumes. Less obvious forms of urban air pollution also occur. Under the influence of sunlight, nitrogen and VOCs may react together to form photochemical smog, containing the invisible gas ozone, a potentially greater threat to human health. In addition, of course, vehicles emit the greenhouse gas carbon dioxide.
Important ùbut less direct ù factors influencing pressures on the atmosphere are the size of the human population, its growth rate and the pattern of consumption of each individual. AustraliaÆs population of 18 million lives in relative affluence and is increasing at a rate of about 1.6 per cent per year, a rate higher than in most OECD countries. Expected economic growth and the continued growth of the population mean that the countryÆs demand for energy is also likely to continue to increase.
\BDescription:\b Alice Aprings after heavy rains \I(Peter Jarver)\i
Recent analysis indicates that the greenhouse warming effect could lead to a rise in sea-level. These rises have been assumed to be in proportion to temperature changes based on previously recorded observations.
Possible physical reasons accounting for sea-level rise are the thermal expansion of sea water, and the partial melting of mountain glaciers and the fringes of high-altitude ice caps as the temperature increases.
\BDescription:\b Rising waters in the Todd River \I(Peter Jarver)\i
#
"Tropical Cyclones and Storms",7,"f\6\3_0089.jpg","c","0"
Marine engineers believe that the greenhouse effect will impact on coast and marine structure and development. One of the most damaging effects may be the potential increase in the intensity, frequency and distribution of tropical cyclones.
A theory in climatology suggests that there is a threshold of sea-surface temperature related to cyclone occurrence. If the temperature increases up to 2 degrees Celsius, the cyclone belt in Australia could potentially be extended about 600 km further south on both the east and west coast.
The 2 degrees Celsius of sea-surface temperature increase, such as from 27 to 29 degrees, would cause a decrease in the minimum sustainable pressure. This would produce an expected increase of 11% in peak wind gusts and a 20% increase in wind pressure on structures.
\BDescription:\b Flooding in north-west NSW \I(DFAT)\i
There is a possibility that temperature, wind and rainfall might all increase in summer as a result of the greenhouse effect, while the temperature and wind could cancel the rainfall effect. The overall result appears to be an increase of bushfire danger in summer under the future warmer climate conditions.
However, fire intensities and ignition patterns also depend on other factors, such as relative humidity, the productivity of forests and population patterns. Further study in this area is required.
It is expected that the greenhouse effect in Australia will intensify monsoon circulation, resulting in a possible increase of up to 50% in rainfall potential in the northern half of Australia. With respect to summer rainfall increases, flooding in those areas affected would be intensified.
On the contrary, the greenhouse warming effect may move the subtropical high pressure systems southwards. Winter rain may decline by up to 20% and in some regions, such as Western Australia, may decline by up to 25%. The reduction of rainfall would affect the irrigation systems.
Meanwhile, ground water recharge is also expected to be severely reduced. All of these indicate a possible shortage of water supplies to meet future demand.
\BDescription:\b The Todd River in \JAlice Springs\j \I(DFAT)\i
#
"Effects on Wildlife",10,"g\10\7_0011.jpg","c","mozzie0"
In the long term, Australia's flora and fauna would likely to be severely affected by rapid climate change. Changes in the wildlife regime, in terms of density and extent, are predicted to be substantial.
The predicted 20% reduction in winter rainfall in the south-west of Western Australia might have a significant effect on the wetlands. Many of the remaining seasonal wetlands would disappear. A number of species of amphibians, reptiles and birds would disappear rapidly from the drier margins of the wheatbelt.
\BDescription:\b Victoria Highway, west of Katherine \I(Peter Jarver)\i
The enhanced greenhouse effect is a global problem that requires global responses. Effective global responses will only be achieved by international agreements, such as the United Nations Framework Convention on Climate Change (FCCC), supported by effective national emission reduction and other response programs. Although Australia only produces one to two per cent of total world emissions, we need to play our part in solving the problem.
More than 150 countries signed the United Nations Framework Convention on Climate Change at the 1992 Rio Earth Summit. It came into force in March 1994. At the time of the first session of the Conference of the Parties (March 1995), 127 countries had ratified it. In December 1992, Australia (an Annex I (developed) country under the Convention) became the ninth nation to ratify. The stated aim of the Convention is to achieve:
\Iæ...stabilisation of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Such a level should be achieved within a time-frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner.Æ\i
The Convention recognises that developed countries must take the lead in reducing greenhouse gas emissions.
Australia's responses are based on, and determined by, our conditions ù our high dependence on fossil fuels (particularly for power generation) and the large agricultural sector. The latter contributes significantly to carbon dioxide emissions from land-use changes and to methane emissions from our large livestock population. Therefore, measures must range across all sectors of the economy; government, industry, agricultural enterprises and individual householders all have a role to play.
Our relatively high dependence on fossil fuels (compared with other OECD countries), the lack of nuclear power and the limited opportunities for hydro-electricity generation all restrict the available options to reduce carbon dioxide emissions. However, we have large reserves of natural gas ù the least carbon-intensive of the three main fossil fuels (coal, oil and gas). There is potential for substituting natural gas for coal in some applications. As well, Australia's climate provides abundant supplies of renewable energy sources such as solar and wind power, although their development and use have so far been limited.
\BDescription:\b A road train \I(DFAT)\i
#
"Sources of Air Pollution",12,0.jpg,The early spraying of DDT on crops,ddt2.avi
Since the last century, air quality has been recognised as a major environmental concern. In many industrialised countries, air pollution from man-made sources has threatened public health and welfare.
Although air pollution was initially a local problem, it is now widely accepted that human activities can alter the chemistry and physics of the global atmosphere. Two global issues, the greenhouse effect and stratospheric ozone depletion, are world-wide concerns.
Man-made emission sources of air pollutants can broadly be identified in the three categories below:
ò mobile sources such as motor vehicles, aircraft, ships and railway locomotives;
ò stationary sources which include emissions from industrial processes such as aluminium smelting and electrolytic treatment, the combustion of fuels for both industrial and domestic purposes, use of paints, coatings and solvents, and waste treatment;
ò miscellaneous sources such as gas leakage, fire, and use of pesticides.
"Common Air Pollutants",13,"g\10\2_0078.jpg","c","fire0"
Some of the most common air pollutants are listed below.
\BCarbon monoxide\b
A product of incomplete combustion, carbon monoxide (CO), is found in the exhaust emissions of all motor vehicles. As an air quality issue, concern is mainly confined to inner city regions with high traffic density. High winter-time concentrations of CO in some suburban areas can be related to the use of wood fires and combustion stoves. However, recorded values are strongly dependent on the precise siting of the measuring instruments. It is therefore difficult to carry out true comparisons between cities because instruments in some are located very close to high-density traffic flows. In the past ten years, Sydney, Perth, Adelaide and Canberra have all exceeded the NH&MRC eight-hour CO guideline (nine ppm) in locations close to high traffic flows.
\BSulphur dioxide\b
By and large, Australian cities do not have a sulphur dioxide problem, primarily because fuels used are low in sulphur and also because power stations are not located in urban areas. Some industrial sources of sulphur dioxide do exist, such as oil refineries on the outskirts of urban areas, and these can pose local problems.
Annual sulphur dioxide averages in Melbourne and Sydney are substantially below the 0.02 ppm guideline. MelbourneÆs average for the period 1980û84 was 0.002 ppm, which compares well with, for example, TokyoÆs average of 0.01 ppm in 1988û89 or New YorkÆs of 0.015 ppm in 1986û87. Highest annual one-hour sulphur dioxide concentrations measured in most Australian capital cities are also well below the NH&MRC guideline.
\BOxides of Nitrogen\b
In the natural nitrogen cycle, oxides of nitrogen are produced from processes in air, soil and water, such as lightning and soil biological processes. They can also be produced from man-made sources such as fossil fuel combustion, biomass burning, cultivated soils and the intensive use of fertilisers.
Nitrogen oxide contributes to the greenhouse effect and the depletion of stratospheric ozone.
\BLead\b
Lead is one of the most significant air pollutants owing to its toxic nature, particularly in its effects on young children. The pollutant sources of lead include: petrol engines, lead smelters and refineries, combustion of recycled sump oil and other materials, and battery manufacture. As with other air pollutants, it can move over long distances.
\BDustfall\b
Dust is the most common air pollutant. It is generated from a variety of sources, such as industry, mining and agricultural activities, construction and demolition, and transport, as well as natural sources such as soil erosion by wind.
\BOzone\b
Tropospheric ozone is a secondary air pollutant, formed in the process of photochemical reactions among other chemicals. It is also regarded as a greenhouse gas.
Ozone is formed when atomic oxygen reacts with oxygen in the air (atomic oxygen is formed when nitrogen dioxide absorbs sunlight). Since the process is very complicated, there is no reliable estimation of ozone concentrations available.
In Australian capital cities such as Melbourne and Sydney, the level of ozone has decreased since 1982, but the concentrations still exceed the acceptable limit.
\BFluoride\b
Fluoride is a chemical which has been recognised as one of the traditional pollutants because of its effects on vegetation and livestock, but it also has a limited effect on the human body.
The major emission sources of fluoride are industrial processes, such as aluminium smelting, phosphate fertiliser production, and brick and glass making.
Although fluoride emission sources are widespread, there is a lack of information on emissions.
\BDescription:\b Burning off \I(DFAT)\i
#
"Effects of Air Pollutants",14,"g\10\1_0053.jpg","c","0"
Air pollutants can have a significant effect on the physical and chemical properties of the atmosphere. They also affect economic materials and structures, human health, wildlife and vegetation.
The affect on physical and chemical properties may be obvious such as in the case of heavy smoke, or there may be subtle effects, for example, on urban temperature or regional precipitation.
Regarding the economic impacts, air pollutants can cause damage to non-living material in many ways, such as corrosion of metal, cracking of rubber, soiling and eroding of building surfaces, deterioration of works of art, and fading of dyed materials.
The significant affect of air pollutants, such as sulphur dioxide and fluoride gases on vegetation, has been one of the earliest manifestations of air pollution. Such effects can be either visible or subtle.
The affects of air pollution on personal or community health include acute sickness or even death, insidious or chronic disease, shortening of life, impairment of growth or development, alteration of important physiological functions, impairment of performance, and storage of potentially harmful material in the body.
\BDescription:\b Manufacturing can cause pollution \I(DFAT)\i
#
"Cars and Unleaded Petrol",15,"spread305.spr","c","0"
\BKey to Table:\b
\B*\b Leaded petrol should be used every fifth fill.
\BHonda:\b All pre-1986 Honda vehicles are capable of being operated on unleaded fuel but must use one tank of leaded fuel after every two tanks of unleaded fuel.
\BPorsche:\b Porsche recommends one tank of leaded after each three tanks of premium unleaded.
\BToyota:\b Some listed Toyota vehicles may require engine adjustment to enable operation on regular unleaded petrol. Any queries should be directed to Toyota.
#
!,!,!,!,!
10#
39,This is a null field
"Saving Energy, Fuel and Water",1,"0","g","0"
This section is full of great ideas on how to be green - save energy, fuel, and water in Australia. You can use the \INext Page\i button, or the \IGo To Page\i button in the Toolbar to browse through this section, or perhaps you would like to move directly to the section that interests you. You can select from the following options:
\JIt's Easy to Save Energy\j
\JIt's Easy to Save Fuel\j
\JIt's Easy to Save Water\j
\JRecycling\j
\JGreen Cleaning\j
#
"It's Easy to Save Energy",2,"g\10\2_0049.jpg","c","0"
Energy conservation is probably the easiest step to take in home ecology because you can see the effects almost immediately. The lower your energy bill, the better you are doing.
The average family wastes more energy than it actually uses. Reducing your energy use is just a matter of changing habits, for example, switch off the lights when you leave a room, close the door behind you or turn off the TV if no-one is watching it.
This section is full of energy-saving ideas and tips to help you run a more energy-efficient home.
\BDescription:\b A recycling depot \I(DFAT)\i
#
"Fossil Fuels",3,"g\10\1_0030.jpg","c","0"
Energy is vital for many of our basic needs like transport, heating and food preparation. We rely heavily on burning fossil fuels to create this energy - this in turn has an enormous influence on our environment.
\BCoal\b
Coal is the most plentiful fossil fuel and is also the most polluting when burned. Carbon dioxide emissions from the combustion of coal are increasing the carbon dioxide content of the atmosphere and threatening to cause climatic changes through the Greenhouse Effect.
Emissions of sulphur dioxide and oxides of nitrogen from coal-fired power stations are involved in the production of acid rain. An estimated 100 million tonnes of sulphur dioxide are released annually into the atmosphere.
This pollution could be reduced by washing and crushing the coal before it is burnt. Although some coal is washed, there is a general resistance because of the added expense.
Mining for coal can severely degrade the land and mining wastes poison the environment. Added to this is the risk to aquatic life through waterborne pollution.
\BOil\b
It is estimated that the world's current oil reserves will be depleted in about 30 years. There is probably another 30 years' supply in as yet undiscovered oil resources. No matter how you look at it, time is running out and costs will soar as oil becomes increasingly scarce.
Over 2.5 billion tonnes of oil are consumed around the world annually. More than 3 million tonnes of this is discharged into the ocean, either through accidental spillage or the washing of tanks. This can cause enormous losses to all forms of marine life including birds, fish and plankton.
Oil is refined to separate the crude oil into different grades. This process causes both air and water pollution - 200,000 tonnes of oil pollute our oceans annually through seepage and accidental loss from refineries.
\BGas\b
Natural gas is the cleanest of all the fossil fuels. Unfortunately this resource is unevenly distributed - the difficulty of transporting gas makes it a viable option for only a few countries. Burning gas still creates a certain amount of air pollution and laying pipelines can be destructive to habitats and wildlife.
\BDescription:\b Gas refinery \I(DFAT)\i
#
"Alternative Energy",4,3_0055.jpg,c,0
With non-renewable, polluting energy sources like fossil fuel dwindling, it's time to invest in renewable, clean energy sources.
\BSolar power\b
Solar power is the least polluting form of energy you can use in the home. Although only .01 per cent of global energy is currently solar, there has been a massive investment in solar technology in recent years.
The world's largest solar plant is The Solar One in California. It provides the energy needs of around 2,000 homes. The future of solar energy is looking brighter although in some countries, like the UK, only co-generation systems may be feasible.
\BWind power\b
Wind power is another source of clean power. There are many successful examples of the use of wind to produce energy. In the USA over 10,000 windmills generate as much electricity as a conventional power station.
California anticipates that one fifth of its electricity will be produced by wind power by the end of the century. In Denmark, 16 windmills now supply one tenth of the electricity supplied to 4,000 residents.
\BOcean, geothermal and hydropower\b
These are other potential sources of energy for the future.
\BDescription:\b Solar powered car \I(DFAT)\i
#
"Building a Home",5,"g\10\tony15.jpg","c","hammer10"
If you are building your own home there is no better time to get it right energy wise. Planning for energy conservation early on in the construction stage may mean no extra cost.
Let your architect know energy efficiency is an important design consideration. If you are buying a project home, look at the plans critically.
\BChecklist\b
* Properly insulated walls and ceilings and lofts.
* Verandahs for protective external shading and a useful outdoor living space.
* Building materials that suit the climate.
* Skylights to improve natural light.
* Windows that let the winter sun in and keep the summer sun out. If you do want windows on the side of the house that faces the summer sun, they should be as small as possible and be either fixed with external blinds or shaded by nearby buildings, trees or shrubs.
Arrange windows to maximise ventilation in summer. Avoid aluminium windows and roofing. Vast amounts of energy are used to produce aluminium; rainforests are cleared to mine the bauxite needed.
* Double-glazed windows and doors.
* Weather-stripped doors and windows.
* Plantation grown timber (not rainforest timbers) for building and furniture.
* Floor coverings to suit the climate - carpets for cool climates, tile or wooden floors for warm climates.
* A solar hot water system inside - external hot water systems often suffer greater heat loss. The hot water system should be as close to the kitchen and main bathroom as possible to reduce the time it takes for hot water to flow through long pipes.
\BDescription:\b A residential construction site \I(Webster Publishing)\i
#
"Your Existing Home",6,"g\10\tony50.jpg","f","0"
There are several ways you can make your existing home more energy-efficient. Even though these changes will cost you money initially, many of them will pay for themselves over and over again as energy costs continue to rise.
\BChecklist\b
* Install a solar hot water system.
* Fix weather strips to your doors and windows.
* Insulate your home. Heat rises and escapes out the top of the house and the summer sun beats down on it. Make it a priority to insulate your roof. Ideally, the outer walls should be insulated as well but this can be expensive.
* Attach awnings to shade from the summer sun.
* Landscape for energy conservation. Plant windbreaks to obstruct the prevailing cold winds, plant deciduous trees that will allow the winter sun through but block the harsh summer sun.
\BDescription:\b Solar panels installed on a roof \I(Webster Publishing)\i
#
"Heating/Cooling",7,"g\10\house.jpg","c","0"
\BHeating\b
Plugging draughts can save you up to 20% of your annual heating bill as well as adding to your general comfort.
Your first task is to assess how well your rooms retain heat. Heating a draughty room will prove expensive and ineffective.
Fitting your windows and doors with weather strips is one of the most efficient ways to eliminate draughts. If you stand inside your closed window on a breezy day and still feel a draught then you need weather strips. A variety of easy-to-install weather stripping options are available from your local hardware store.
The best way to isolate draughts is to close all your windows and doors, light a stick of incense or a candle and walk around your home. The smoke trail or flickering candle will be a good guide to where your trouble spots are.
Insulate your roof. Up to 35% of heat loss or gain is through the ceiling.
Double-glazed windows can save up to 30% on your heating bill.
Snake-shaped bolsters are an easy, cheap way to prevent draughts from under doors. These are very simple to make, even without a sewing machine.
Curtains cut down draughts from windows - the longer they are the more effective they'll be. Choose light colours that reflect both heat and light and use thermal-backed lining fabric. Clean windows will let more sun into rooms on sunny winter days so keep the curtains open. On cloudy days or at night, close the curtains to avoid heat loss.
An unused fireplace can be a major source of draughts, If you don't use it, install an efficient combustion stove, brick it up or block it.
\BCooling\b
Open windows to encourage cooling breezes.
Make sure you have good insulation as this reduces heat entering your home from outside.
Light-coloured exterior walls reflect sunlight and heat.
Plant trees around the home for shade. Deciduous trees provide shade in summer and allow the sunlight in when they shed their leaves in winter.
Use air conditioners sparingly as they use CFCs. If you do use an air conditioner it need never be set lower than 25 degrees Celsius. Check and clean your filters regularly as the fans have to work much harder when the filters are dirty. Better still, use a ceiling fan.
\BDescription:\b An average suburban home \I(Webster Publishing)\i
#
"Lighting",8,"g\10\1_0027.jpg","f","people10"
The energy output of conventional incandescent light bulbs is approximately 90% heat and only 10% light. They are the least efficient artificial light source available.
The wattage of a globe refers to the energy used, not the light emitted. For example, a 100 watt globe only gives 50% more light than four 25 watt globes.
Buy globes to suit your needs only. Bright lights are not really necessary in most areas of the home - reduce where you can but don't go to extremes. Always have enough light for safety and to avoid eye strain.
Keep your light bulbs clean - dirty bulbs can reduce lighting efficiency by up to 50%.
Light-coloured walls can help save energy as they reduce the amount of light needed in a room.
Fit dimmers to light switches - they reduce the amount of electricity used.
Use fluorescent tubes. They are about four times more efficient than incandescent bulbs and will last at least five times longer. The circular or U-shaped tubes are a little more efficient than the straight variety. The new, thinner fluorescent tubes use around 10% less energy again.
Although fluorescent lights are more expensive initially they will last 5-10 times longer than an incandescent bulb and only use around one quarter of the energy. When first switched on they consume the energy equivalent of 20 minutes running time. Use them in places like the kitchen where lights stay on for longer.
Fluorescent bulbs that fit into ordinary sockets are now available. You may have to buy them through specialist lighting stores, but they are worth searching for.
Only light rooms you are actually occupying - when you leave a room get into the habit of switching the light off.
For maximum light efficiency, place lamps in the corner of the room to take advantage of two walls to reflect light.
\BDescription:\b Lighting in an office \I(DFAT)\i
#
"It's Easy to Save Fuel",9,"f\4\3_0059.jpg","c","0"
Cars have changed our lives by giving us undreamt-of mobility. Today we think nothing of travelling 50-100 kilometres to work everyday, when less than a century ago many people didn't venture that far in a lifetime.
Everything has its price. Motor vehicles are a major cause of air pollution. They emit unburnt hydrocarbons, carbon monoxide, oxides of nitrogen and lead into the atmosphere to create acid rain and photochemical smog.
Modern cities and towns have been shaped by wheels to the extent that one third of the land in an average city is taken up by carparks and roads. Outside cities, freeways and other major roads consume even larger areas. Smaller roads are a problem when they go through environmentally sensitive areas.
This section has lots of tips on how you can reduce the amount of air pollution you cause, save fuel and be more aware of the environment.
Despite tighter environmental regulations to cut down on car emissions, and improvements in fuel economy, more people now own and use cars, and the volume of pollutants produced has also risen. It's time to invest in clean, renewable energy sources such as solar, electric and hydrogen-powered transport.
Every item you buy from the supermarket, every appliance, book, beer, pen and so on has been transported from where it was produced and packaged to the point of sale. Goods often travel thousands of kilometres to reach their destination.
Most food used to be produced by the community for the community. Once commercial growers began to specialise, large amounts of one crop were grown to supply both local and export markets. Today there are massive wheat belts, dairying areas and fruit-growing regions across the world.
Many countries have centralised their processing and distribution operations in major cities. Food is grown in the country, taken to the city to be processed and packaged, then transported back to the country for sale.
This system is a drain on fuel resources and adds to our pollution problems. Always make it a priority to buy locally produced and packaged goods. Check the label before you buy.
\BDescription:\b A road train \I(DFAT)\i
#
"How to Cut Down",11,"g\10\1_0033.jpg","c","car20"
Before you look at how you can cut down on fuel, try to gauge how often you use your car.
Keep a diary of your car trips - where you went, distance travelled, how many passengers, and weather conditions. Work out where you can cut down. Set yourself an easy target and try to eliminate at least one trip a week.
When the weather is fine, and your intended trip is less than a 20 minute walk, why not get some exercise and walk instead?
Do you really need two cars? If one of them sits parked outside work each day, why not join a car pool or use public transport?
Public transport is a very convenient form of travelling and needs your support to run efficiently. No parking, no waiting at lights or sitting in traffic jams. A bus or train ride can also be therapeutic, providing a much-needed opportunity to sit and think, nap, read a book or simply watch the world go by.
If you pick up the children every afternoon from school, and see other parents from your street doing the same, approach them about taking turns. Why send three cars to the same destination when one can do the job?
\BDescription:\b Toyota car factory \I(DFAT)\i
#
"Driving",12,"a\1\tony62.jpg","c","traffic0"
The way you drive can significantly reduce fuel consumption and pollution. Drive a car that uses lead-free petrol. Remember, diesel fuel has no lead emissions.
Below is a list of actions you can take to reduce the amount of fuel you use every day.
Slow down and save petrol. Consumption increases with speed. A speed reduction from 100 kph to 80 kph can result in a 25% reduction in fuel. Electronic ignitions also save on fuel.
Avoid peak hour traffic when possible (as if you don't already!) - more fuel is consumed in stop/start traffic.
Think ahead when you drive. When approaching your turn, move into the appropriate lane in plenty of time.
Switch off the engine when stuck in a traffic jam. There's no need to keep the car idling.
The more weight in the car the more fuel you use. Check that you are not carrying unnecessary loads in your boot.
Don't overfill your petrol tank - it will only be lost through the overflow pipe.
Remove roof racks if you are not using them. Any fitted extras that affect the aerodynamics of your car increase fuel consumption.
Inflate your tyres to the correct pressure to reduce both petrol consumption and wear on tyres.
Drive smoothly, accelerate gently and avoid panic braking. This reduces fuel consumption, and saves unnecessary wear and tear on your car.
Don't drive with your foot on the brake. You use more fuel and create unnecessary stress on your vehicle.
Don't overuse your choke. As soon as the car is running smoothly, release the choke.
Be courteous when driving. Slow down in residential areas and near schools. Don't race your engine impatiently at pedestrian crossings or traffic lights.
Don't let other drivers bully you into going faster. Choose your own speed and stick to it.
Be aware of pedestrians, cyclists and wildlife - always anticipate their presence on the road.
Public transport is up to 60 times more fuel-efficient than travelling solo in your car. It is cheaper and often easier to catch a bus or a train or a tube, even though public transport does have its inadequacies. The best way you can help to support and improve the service is to use it.
If you rely on public transport as a regular means of travel but find the service inadequate, write to the relevant transport authority suggesting ways they could improve the service.
Find out how other people feel about the current service in your area and encourage them to write also. Leave petitions in local shops. Your collective voice does count with future planning.
Get a current timetable from your local services if it's a while since you used public transport. Also ask for information on reduced prices and concession tickets.
\BDescription:\b The Sydney monorail \I(DFAT)\i
#
"Alternative Methods of Transport",14,3_0037.jpg,c,0
Cycling is an enjoyable, efficient and convenient way to travel. A bicycle is non-polluting, cheap to maintain and helps to keep you healthy.
People should be encouraged to use bicycles more, and the best way to do that is to improve safety standards. If your town or city is short on bicycle paths and lanes, write to the local planning authorities and register concern. Get in touch with a bicycle club and enquire about campaigns related to safer cycling.
If the idea of safe cycling through city traffic is too daunting, why not become a weekend cyclist? Cycling is relaxing, lots of fun and great for sightseeing.
Walking is not only good for your health, it puts you in touch with your surroundings. Try leaving the car at home tomorrow. You will be astounded at the things you never noticed before.
Walking gives you time to think and plan - a real bonus in today's busy world. Choose routes that have the least traffic. Take back streets and enjoy the peace.
\BDescription:\b Walking - an alternative way of getting around \I(DFAT)\i
#
"It's Easy to Save Water",15,"g\10\garden2.jpg","c","0"
Fresh, clean water is no longer something that can be taken for granted.
Rainwater tanks, which are becoming more and more popular are an excellent way to save water. They are more popular in the country (where there is less rain) than in cities (where people tend to take water for granted). With the Australian population increasing by 2 per cent every year, they may one day be a necessity for every household to have.
Following are ten golden rules for saving water.
* Fix dripping taps promptly
* Choose phosphate-free detergent
* Use recycled, unbleached toilet paper
* Never dispose of toxic waste down the drain
* Shower instead of bathing
* Turn taps off properly
* Observe water bans
* Reuse washing water in the garden
* Water your garden in the early morning or early evening
* Don't do your laundry until you have a full load.
\BDescription:\b Water your garden in the early morning or evening \I(Tanya Hamilton)\i
#
"Water Pollution",16,"g\10\2_0052.jpg","f","0"
Rivers, lakes and oceans have always been used as dumping grounds for waste. This includes sewage pumped directly into the ocean, domestic outfall from drains and highly toxic wastes from industry and agriculture. This waste has caused phenomenal damage to marine ecosystems, and made many of the beaches near cities and towns a potential health risk.
The ocean currents that bring sewage back to our beaches also circulate waste far beyond our back doors. High levels of DDT have been detected in Antarctic penguins, thousands of miles from its source.
Remember the basic code - if in doubt, leave it out. Most waste isn't suitable for disposal through the sewerage system.
* Never pour cooking oil or fat down the sink - it doesn't mix with water. Solidified fat can go on the compost or be put out with the garbage. Oil should be returned to its container and put out with the garbage, or buried in the garden away from plants.
* Detergents damage the environment, particularly those containing phosphates. Try using pure soap for washing clothes as well as dishes. If you do use detergents, use them sparingly and buy biodegradable brands only. If you use pure soap for washing up, the water can be used to water your garden afterwards.
* Keep your toiletries simple - pure soap and basic shampoos. Shop around for brands that don't have harmful additives.
* Avoid white or coloured toilet paper - they contain dyes and bleaches that are pollutants. Toilet paper marked 'suitable for septic tanks' is usually free of these, as is recycled toilet paper.
* Avoid chemical cleaners for your toilet. The flush toilet was specifically designed for hygiene without chemicals. The coloured variety are generally more cosmetic than cleansing. A toilet brush and some vinegar will do the job just as well.
* Don't throw coffee grounds and tea leaves down the sink or toilet. Put them on your garden instead.
* Never pour milk down the sink - it's such a waste.
* Disposable nappies are a major waste problem. The billions that are sold and disposed of annually don't degrade. If you buy disposable nappies, put them in your bin for collection, never into the sewerage system. Why not try a nappy service? It works out cheaper and the door-to-door service will be a time-saver.
* Sanitary towels should be wrapped and put out with the garbage - never flush them down the toilet.
* Condoms should go into the garbage - never down the toilet.
* Wrap leftover paint and turpentine before putting it in your bin. Choose water-based paints over oil-based. Clean your brushes away from drains.
* Never put toxic substances like insecticides or kerosene down the drain.
* Ashtrays should never be emptied down the toilet and don't dispose of cigarette butts down the drain.
* Only use non-toxic anti-fouling paint to prevent encrustations. Toxic paints leach into the water and can have a devastating effect on marine life.
* Check your boat regularly to ensure it is not leaking oil.
* Don't litter. Take your rubbish home with you.
* If a company is a proven polluter, don't buy their product or use their services.
\BDescription:\b \JCSIRO\j water testing \I(DFAT)\i
#
"Bottled Water",17,"g\10\a4_0067.jpg","c","0"
Bottled water of every kind has become big business. Some of the leading European brands are on sale all over the world.
The drain on energy resources to package and transport this cleaner-than-clean water is enormous.
Treat bottled water as the luxury it is. Buy a brand that is locally supplied and bottled in recyclable containers.
Why not try the local 'on tap' kind? There are many varieties of water filters available for home use. Some filter out more chemicals and pollutants than others. Shop around for one that best suits your needs.
\BDescription:\b Bottled water \I(Carrie Webster)\i
#
"The Fluoride Issue",18,"g\9\1_0078.jpg","f","0"
When fluoride was tested, it was found that small amounts helped reduce tooth decay. It was also discovered that larger doses caused brittle teeth, mottling and abnormal bone formation. Since then, fluoride has been implicated in a variety of health problems, including cancer.
Fluoride is emitted as a waste product in the smelting of aluminium. Fluoridation, the addition of fluoride to public water supplies, transformed this waste (bulk sodium chloride) into a commercial product - fluoride is now added to most commercial brands of toothpaste and is also available in tablet form.
If you disagree with your water supply being fluoridated, write to your local council and voice your opinion. A water filter can be used to remove fluoride from your water.
\BDescription:\b Lake Jindabyne \I(DFAT)\i
#
"Saving Water in the Kitchen",19,"g\10\kitchen.jpg","c","0"
* Water for drinking and cooking is essential. Running the tap when you prepare vegetables or other food is one of the most common ways to waste water. Half fill the sink with water for these jobs.
* Use the leftover water from jugs and kettles to water your indoor plants or your herb garden. Leftover water can also go on the garden if you don't use harsh detergents.
* Dishwashers are great water wasters. They are high in energy use and rely on particularly harsh detergents. If you need a dishwasher, buy a water/energy efficient model and only use it when you have a full load.
* Waste disposal units are a two-way waste. They use energy and water (about 30 litres per day), and the food scraps they swallow up make valuable composting material.
\BDescription:\b There are many ways to save water in the kitchen \I(Webster Publishing)\i
#
"Saving Water in the Bathroom",20,"g\10\bath.jpg","c","0"
* Turn the tap off when you brush your teeth and take shorter showers. About 30 litres of water per minute rushes down the drain - a few minutes here and there will make all the difference.
* Bathing accounts for the largest share of household water use at over 25 per cent. There are ways you can reduce your water consumption and still be clean.
* An average bath contains enough water to keep a shower running for 15 minutes - shower, don't bathe. Save baths for those special occasions when you want to pamper yourself.
* Try to reduce the length of time you spend in the shower - cutting down by only 2 minutes will save 60 litres of water.
* Water-efficient shower heads and aerators use 2-5 times less water without any noticeable reduction in pressure.
* When washing you hands, half fill the basin then turn the tap off.
* Fix dripping taps immediately - they waste millions of litres annually. Even a very slow leak can waste over 100 litres per month.
* Toilet flushing accounts for almost as much of our domestic use as bathing does - around 25 per cent. Reduce this waste of water by buying a water-efficient unit.
* When you install a new unit, choose a model with a half flush option. The new air-assisted models are designed to use up to 90 per cent less water.
* To test a leaky toilet, put a vegetable dye in the cistern - if the toilet is leaking the dye will come up in the bowl (the more dye, the bigger the leak).
\BDescription:\b A bathroom \I(Webster Publishing)\i
#
"Saving Water in the Laundry",21,"h\1\washer.jpg","c","0"
* Use your washing machine only when you have a full load and reduce the amount of harmful chemicals you use.
* When it's time to buy a new washing machine buy an energy-efficient model that gives you a half load/short cycle option.
* Top-loading machines use more water than front-end loaders - up to 270 litres per load. A twin tub uses around 80 litres per load.
* Reuse your washing water. You can throw it on your garden (but only use mild detergent or pure soap), wash the car with it or even the floors.
\BDescription:\b A laundry \I(Webster Publishing)\i
#
"Saving Water Outdoors",22,"h\1\carwash.jpg","c","0"
Although outdoor water usage doesn't account for a large proportion of overall domestic use, it's an area where a high percentage of the water used is wasted.
* Avoid washing the car unless there's a real need. Use a bucket for washing and the hose only for rinsing. Hundreds of litres are wasted while the hose lays idle.
* Don't hose the driveway and paths. A good, stiff broom will clean them much more effectively.
* Install rainwater tanks - the extra water can be used for drinking or for rinsing hair for that special glow.
* For maximum absorption, water your garden in the early morning or late afternoon/early evening. If you water in the heat of the day most of the water will evaporate. Your garden only needs one good soaking a week. Frequent watering will encourage thirsty plants.
* Use mulch - it increases the benefit of the water you use by reducing evaporation.
* When you use a sprinkler remember to move it around and to turn it off. Automatic timers can take the guess work out of this.
* Drip watering systems are the most water-efficient option for watering your garden - they slowly release drips to the base of plants where the water is needed most.
\BDescription:\b Use a bucket to wash your car and don't leave the hose running \I(Webster Publishing)\i
#
"Saving our Oceans",23,"h\1\a4_0047.jpg","c","0"
Seven-tenths of the planet is covered with oceans that make up one continuous ecosystem. Pollutants entering the system in one part of the world are detected in marine life thousands of kilometres away.
Oceans contain a multitude of diverse and rich environments, only a fraction of which have been explored. Some areas flourish with marine life while others are barren stretches of underwater sand. The Great Barrier Reef in Australia is the aquatic equivalent of a teeming rainforest and is home to over 3,000 different species.
Every pollutant we add to our oceans has an adverse effect on the future resources the sea can offer. You can help by following these guidelines:
* Avoid using toxic chemicals - they make their way into the system via airborne pollution or runoff.
* Think before you flush!
* Support campaigns to save threatened wildlife habitat areas.
* Lobby your local council for a better sewerage system.
* Boycott companies known for pollution and dumping waste.
\BDescription:\b View from Manly \I(Carrie Webster)\i
#
"Recycling",24,"h\1\2_0039.jpg","c","0"
Around 500 BC the Greeks introduced the first laws against dumping garbage in the streets. Municipal dumping areas were organised in Athens no less than two kilometres from the city walls. Unfortunately this practice of waste removal disappeared in medieval Europe, where garbage was again dumped in the streets and thrown out of windows.
After the industrial revolution, garbage was piled up in the countryside outside cities. As the cities grew and the countryside shrank, rat infestations and noxious odours became intolerable. Pits were dug in an attempt to confine the waste.
The first incineration of municipal waste was tested in England in 1874. Although the burning of waste could reduce its volume by 70% to 90%, the cost of incinerators was prohibitive, and many people opposed this method when their air quality deteriorated. Burying waste once again became the preferred choice.
\BDescription:\b Clean up Australia Day is designed to encourage environmental awareness within Australian communities \I(DFAT)\i
#
"Do the Right Thing",25,"h\1\2_0053.jpg","c","0"
Litter is a major problem the world over, not just because it's unsightly, but because IT KILLS. Thousands of sea mammals, birds and other wildlife species are killed annually by becoming ensnared in plastic or ingesting it.
Always take a litter bag if you are spending the day outdoors. Never throw rubbish out the car windows - hang a litter bag from your dashboard or keep a box in the back.
If you see someone littering go up and tell them politely that they have dropped something. Pick up litter, even if it isn't yours.
Report littering - if you witness any major dumping of waste, report it to the authorities. There is no point in saying 'I don't want any trouble' or 'I don't want to get involved' - you already are! Litter affects everyone's lives.
\BDescription:\b Clean Up Australia Day \I(DFAT)\i
#
"Buying Recycled",26,"h\1\1_0007.jpg","c","0"
Recycling is a major step towards a sustainable future and needs your participation to work. One of the most important contributions you can make to its future, apart from recycling your own waste, is to buy products that use recycled material in their manufacture.
Talk to your friends about buying recycled products, particularly those in business who buy large quantities of paper or other resources.
\BDescription:\b Advertisement for recycling \I(DFAT)\i
#
"Why Recycle?",27,"g\10\2_0040.jpg","c","0"
\BRecycle to save energy:\b every time energy is used up, so are vital, non-renewable resources. The energy used to produce the metal for one aluminium can is the same as that needed to recycle twenty. The energy required to make 300 aluminium cans is equivalent to 3 weeks petrol for an average motorist.
\BRecycle to save resources:\b natural resources will last longer if you recycle instead of using raw materials - each tonne of recycled paper saves half a hectare of trees. Just recycling the print run of a Sunday edition of the \INew York Times\i would leave 75,000 trees standing.
\BRecycle to save money:\b recycling can reduce your household garbage by up to 80% and this saves on collection costs. The reduced cost, combined with the money your local councils can make by selling the waste, means more money spent on improving your local area and community services.
\BRecycle to save space:\b if waste is being recycled, the amount of land needed for tipping sites will be reduced. The average consumer produces about one tonne of waste annually - vast areas of land are needed to accommodate this.
\BRecycle to create jobs:\b recycling is a modern growth industry and in future will require ever greater numbers of people to collect and sort goods, and to work in industries which use recycled materials. The sale of recyclable materials can earn money for schools, clubs and charities.
\BRecycle to reduce pollution:\b recycling materials is more energy efficient than starting from scratch using virgin materials - this means a general reduction in air, water and land pollution from factories and tips.
\BDescription:\b Clean Up Australia Day participants separate recyclable rubbish from the rest \I(DFAT)\i
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"Cut Down on Waste",28,"h\1\2_0057.jpg","c","0"
Recycling is a great way to conserve resources - but an even better alternative is to not create the waste in the first place!
Two important ways to minimise the problem are:
1. Maximise the life of the product in its original form - use things until they are really worn out.
2. Reduce the amount of waste produced. This is a major consideration when you do your weekly shop.
Make your selections not only on the nutritional and dollar values of a product but also on the amount of packaging. Assess the product's disposability once it becomes garbage.
In industrial countries, packaging constitutes 30-50% of household waste. That's why it's so important to think about the recycling potential of packaging at the time of purchase.
\BDescription:\b Recycled paper products \I(DFAT)\i
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"Make Things Last",29,"h\1\2_0057.jpg","c","0"
Here are just a few suggestions for ways you can extend the life of a product in its original form.
* Start an 'Ecology Store' in your home. Store reusable items such as paper, string, boxes, cartons, plastic containers, ribbons, wool and fabrics to provide materials as the need arises. Set aside a drawer or cupboard for this purpose and encourage the whole family to use it.
* Write on both sides of your note paper.
* Reuse envelopes by crossing out the old addresses or sticking a new address label on.
* Recycle your scrap paper by making your own paper.
* Save gift wrapping, ribbons and string for reuse.
* Reuse jam jars. Wash and use them again for food storage, keeping nails in, pencil holders and for the children to use in all sorts of ways (to hold water and paintbrushes, for example).
* Egg cartons make perfect seedling trays.
* Pass on magazines or books. Pass them round the neighbourhood or drop them at your local hospital or nursing home.
* Decorate old glass bottles and jars by painting them. This was all the rage in Victorian times for keeping lavender water, bath salts and other toiletries in. Store herbed oils and vinegars in bottles. Seal with corks.
* Revive old mascara dispensers in hot water for a few minutes and lengthen their life.
* Old toothbrushes can be used for cleaning those small, hard-to-get-at places around the home.
* Use old tyres as planters. Fill them with topsoil and plant with tomatoes, strawberries or herbs.
* Recycle children's clothes by swapping, selling or giving them away. These would make an excellent donation to the local church bazaar or school fete.
* Reuse plastic bags for wrapping sandwiches, keeping stockings tidy and snag-free and storing and freezing foods.
* Start a household 'ragbag' for storing all your clean fabric discards in - torn sheet remnants, dressmaking leftovers, worn out T-shirts. These can be used for so many different jobs - applying waxes and cleaners, washing windows, cleaning the car, sopping up stains or lining a box or basket for a new puppy or kitten.
* Use the better, not-so-worn-out remnants from the ragbag for making all kinds of useful and pretty things - patchwork quilts, rag dolls, doll's house accessories, pot holders, pillow slips.
* Ask about replacement parts and servicing when you purchase any new appliances.
* Learn to do basic repairs yourself. Everyone should be able to sew a straight seam or replace a button. Simple repairs can add years to the life of an item.
* Anticipate where certain things are going to wear out and protect them from the beginning. A rug in the right place will save wear and tear on a brand new carpet.
\BDescription:\b Recycled paper products \I(DFAT)\i
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"Preparing to Recycle",30,"h\1\compost.jpg","c","0"
Most households discard two full bins of waste each week. At least 80% of this rubbish has good recycling potential. Separation of different types of waste is crucial to any recycling program, all you need is a sorting system.
Organic matter is the only type of waste that can be recycled by you in your own home. If you live in a unit or apartment you may have a friend or neighbour whose compost heap can accommodate extra.
Glass, paper and cardboard, metal and organic matter all have excellent recycling potential. Your household waste is made up of:
Glass 10%
Paper and card 30%
Metal 10%
Organic matter 30%
Plastic 8%
Miscellaneous 12%
Always try to reuse plastics instead of throwing them away. The plastic recycling processes currently available can only deal with one type of plastic and there are about 64 plastics commonly in use! The task of sorting all of these plastics is so labour intensive that recycling is unrealistic at this stage.
Miscellaneous waste generally includes items composed of several different substances. This waste has little recycling potential as each item would have to be broken up and the individual materials separated.
\BDescription:\b A compost bin is a good way to cut down on your rubbish \I(Webster Publishing)\i
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"Sorting Food, Glass and Paper",31,"g\10\2_0049.jpg","c","0"
\BFood scraps\b
Keep food scraps and other household wastes separate in the kitchen (a container with a lid is best for this), and deposit regularly onto your compost heap. Organic waste is valuable garden fertiliser and should never go out in the garbage. If you don't have a garden or a compost, share a friend's or neighbour's. Keen gardeners will welcome the extra fertiliser.
\BGlass\b
Remove the lids and tops before adding glass containers to your recycling bin. If the containers are returnable milk bottles, for example, take them back rather than recycle. Any type of glass container is suitable for recycling. Glass can effectively be recycled forever.
\BPaper\b
Newspapers and any other paper products are suitable for recycling. Look out for packets lined with plastic as these can't be recycled. 'High quality' paper such as office, computer or any white paper that has very little inking is particularly sought after by paper millers. Paper is best stored in cardboard boxes for collection or tied with natural fibre string. Don't put paper for recycling into plastic bags.
\BDescription:\b Glass recycling depot \I(DFAT)\i
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"Sorting Steel, Metal and Aluminium",32,"h\1\2_0048.jpg","c","0"
\BSteel cans\b
Rinse cans to remove food scraps and squash them flat.
\BMetal\b
Keep all forms of scrap metal - it's worth money. Look up scrap merchants in your area and find out the current prices for scrap metal and guidelines for sorting.
\BAluminium cans\b
These are worth money! Your children will welcome the chance to earn extra pocket money and local charities will happily take them off your hands. Squash cans flat for collection. Some recycling programs include milk bottle tops, pull tabs and aluminium foil and trays. Rinse first.
Large amounts of energy, water and oil are required in the production of plastics. It's ironic that so many precious resources go into making a virtually indestructible article that is only used briefly - sometimes for no more than a few moments.
Avoid disposable items made from plastic whenever possible. Although currently plastic is not recycled on a large scale, the future is looking a little more promising with pilot programs for recycling domestic plastics being established around the world.
In the meantime the only thing you can do is cut down on the amount of waste plastic you produce.
\BDescription:\b We all should cut down on the plastic bags we use \I(Webster Publishing)\i
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"Avoiding Plastics",34,"g\10\2_0049.jpg","c","0"
Following are a few suggestions on how you can cut down on the amount of waste plastic you produce.
* Avoid buying meat and vegetables prepackaged in plastic and displayed on styrofoam trays. If your supermarket or local shops don't offer unpackaged goods, voice your opinion and shop elsewhere until they change.
* Take your own bag or trolley when you go shopping to avoid accumulating more plastic carry bags. If you don't manage to avoid plastic bags completely, at least ensure you maximise their life by reusing them.
* Avoid using plastic bags and plastic cling wraps in the kitchen. A plate on top of a bowl of leftovers in the fridge does the same job as plastic wrap, or buy a set of storage containers and jars that can be reused for years to come.
* Buy 100% recyclable alternatives to goods packaged in plastic.
* Avoid disposable plates, cups and food utensils.
* Don't buy disposable razors - buy a good razor that relies on disposable blades only.
* Invest in a good pen that will last for years and only requires refills, or buy a fountain pen. Millions of plastic pens are thrown out every year.
* Buy margarine and butter in paper wrappers and transfer to a butter dish. Think about the number of plastic margarine tubs you threw out over the last 12 months. It's frightening when you consider that every other household did the same.
* Buy soft drink in glass bottles, preferably reusable.
* Line your kitchen bin with newspaper rather than plastic bin liners.
\BDescription:\b Recycling material depot \I(DFAT)\i
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"Green Cleaning",35,"h\1\1_0025.jpg","c","0"
By using salt, soda and soap and a little elbow grease, you can help lessen the damage to our environment.
\BAll-purpose cleaner\b
Mix 50 mL of vinegar with 120 mL of bicarbonate of soda and 50 mL of cloudy ammonia.
Mix the ingredients in 4 litres of hot water. This is a safe solution for all areas and can be rinsed off with water. Put the solution in a simple pump-action spray bottle or pour straight on to your cleaning cloth. Shake the mixture well before use. Avoid inhaling ammonia vapour.
\BCane\b
Wipe cane over with a solution of equal parts vinegar and water. Dry out of doors, if possible, on a warm day.
\BCarpets\b
To deodorise and fully clean carpets, mix one part borax (a natural salt) with two parts cornmeal. Sprinkle liberally, leave for about an hour and vacuum. If you have some tough stains, blot with vinegar in soapy water. For quick deodorising, sprinkle the carpet with bicarbonate of soda, then vacuum.
\BDisinfectant\b
Pure tea-tree oil is a natural and effective disinfectant. It can be added to your general cleaners, and is also a handy antiseptic for cuts and bites.
\BLino or tile floors\b
Use the all-purpose cleaner (see above). If you want a lemon-fresh smell, add a tablespoon of lemon essence to the rinse water. You can also use a soap, vinegar and water solution for washing floors.
\BFloor polish\b
Use bees wax to polish. Or melt 1 tablespoon of paraffin wax in a double boiler then add a few drops of lemon essence and apply with a rag. Allow to dry then polish.
\BFurniture polish\b
Rub with a mixture of olive oil and lemon juice or wipe over with a chamois leather wrung out in water and vinegar. Polish with a soft, dry cloth. Or dissolve 1 teaspoon of lemon oil in 1 pint of mineral oil and apply with a rag.
\BHeat marks on furniture\b
Rub with a paste of olive oil or vegetable oil plus salt or cigarette ash. Remove paste and give the piece a coat of wax polish.
\BLeather\b
Remove stains from leather using a solution of vinegar and warm water. To finish, rub over with olive oil.
\BMirrors\b
Use 125 mL of white vinegar mixed with 1 litre of water. Rub dry with a newspaper for an even finish.
\BWood\b
A few drops of vinegar in 250 mL of water is enough for daily or weekly use (60 mL of vinegar to 1 litre of water if you are making a large batch). Dip the cloth in this mixture and wring it out until it is just damp. Run it over the polished surface then buff with a soft cloth.
For more thorough and less frequent polishing, mix two parts vegetable oil or olive oil with one part lemon juice. Shake mixture well before use.
\BVarnished surfaces\b
Wipe over with strained cold tea.
\BVinyl upholstery\b
Wash with a strong solution of cider vinegar then rinse and dry well.
\BWallpaper\b
Remove all dust with a feather duster or vacuum cleaner. Wipe the wall down with 2-day-old, thick slices of bread. For vinyl wallpaper, clean with a warm cloth and white vinegar.
\BWindows\b
Use a solution of 125 mL of white vinegar and 1 litre of water. Rub dry to avoid streaking. If windows are very grubby, wash with soapy water first.
\BDescription:\b \I(DFAT)\i
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"Green Cleaning in Your Kitchen",36,kitchen1.jpg,c,0
Hygiene and daily cleaning are very important in your kitchen because of the grease and condensation caused by cooking. While many chemicals are convenient to use for cleaning, there are pressing environmental reasons to use natural cleaning methods and non-toxic products.
\BAutomatic dishwasher\b
Washing soda can be used instead of commercial brands of detergent. For rinse aids, vinegar will reduce spotting and streaking.
\BBenches and table tops\b
Use bicarbonate of soda, a scourer and a damp cloth to wipe.
\BBlocked drains\b
Use a rubber plunger. Clean grease-blocked drains by soaking with washing soda and hot water, or pour a handful of bicarbonate of soda down the drain, followed by half a cup of vinegar.
Replace the plug and close the drain. Let it sit for a while, then flush with water. Prevent drains blocking in the first place by not pouring grease down your sink.
\BBurnt pots\b
Dissolve 2 teaspoons of bicarbonate of soda in water, bring to the boil and clean when cool. Alternatively, fill the pot with water, add a good handful of salt, bring to the boil and soak overnight. You can also use potato peelings instead of salt (soak overnight and then boil).
Badly burnt pans can be cleaned by gently heating a little olive oil in them. Allow to stand for an hour, pour off the oil into a container (for later disposal) and clean in the usual way. Fill stained pots with water, add the peel and core of an apple and boil mixture to remove marks.
\BDishwashing by hand\b
Hot water and pure soap will remove grease in soft-water areas. Add washing soda in hard-water areas. Use soda and soap dissolved in boiling water for more ingrained dirt.
\BFridge\b
Clean with warm water and soap. To deodorise, wipe down with vanilla essence or leave an open packet of bicarbonate of soda in the fridge.
\BGlass\b
If you live in a hard-water area you may get spotting on glass. Just add vinegar to the final rinse - this works well for windows too.
\BJars\b
To rid jars of musty smells, fill half way with water and add 1 tablespoon of dry mustard. Shake well and stand for 20 minutes then rinse thoroughly. Or put 1 tablespoon each of tea leaves and vinegar in the jar, fill with warm water and stand for 2-3 hours. Rinse well.
\BKettles\b
Boiling equal parts of vinegar and water in the kettle will remove hard water encrustation. A few clean pebbles added to the water will help to break up thick deposits.
\BOvens\b
To clean, make a paste of bicarbonate of soda and water and apply to the inside of a warm oven with a spatula. Leave to dry and then clean off with a stiff brush and very hot water. Wipe the newly cleaned oven with a solution of 1 heaped tablespoon of bicarbonate of soda and 300 mL of water to make cleaning easier next time.
Try to keep your oven clean by wiping it out after each use. To clean oven racks, soak in washing soda dissolved in water.
You can also clean the oven by mixing 250 mL of water with 125 mL of cloudy ammonia and placing this mixture in an oven-proof bowl in a warm oven for 10-15 minutes (oven off). Wipe off grime with a stiff brush and bicarbonate of soda, then wipe with a damp cloth.
\BSinks\b
Clean and disinfect your sink by scouring with salt. You can also use bicarbonate of soda on a damp cloth.
\BDescription:\b A kitchen \I(Webster Publishing)\i
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"Cleaning Special Surfaces",37,"h\1\kitchen2.jpg","c","0"
\BBrass\b
Shine brass using a paste of vinegar and salt. Also try lemon juice or white wine vinegar mixed with bicarbonate of soda, or Worcestershire sauce.
\BChrome\b
Polish with cider vinegar, or dip a dry cloth in ordinary flour and wipe over.
\BCopper\b
Rub with vinegar using a soft cloth. Polish with a dry cloth.
\BPewter\b
Polish with the outer leaves of a cabbage and then buff with a soft cloth.
\BSilver\b
Make a solution of one part washing soda to 20 parts water and put into an aluminium pan (the bubbles created by doing this are not toxic). Dip the silver into the mixture then rinse in hot water and dry with a clean soft cloth.
Alternatively, soak silver for 10-15 minutes in a saucepan containing hot water, a few aluminium bottle tops or a piece of aluminium foil and 1 tablespoon of washing soda.
\BStainless steel\b
Dip a dry cloth in plain flour or cornflour and wipe over for a good shine. Heat marks can be removed by rubbing with a scouring pad and lemon juice.
\BTiles\b
Use white vinegar on a cloth to wipe down greasy tiles. If you apply a wax polish to ceramic tiles, they will be easy to wipe down. For general cleaning, you can also use bicarbonate of soda.
\BDescription:\b A kitchen \I(Webster Publishing)\i
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"Green Cleaning in Your Bathroom",38,bath.jpg,c,0
Your bathroom, like the kitchen, should be kept clean because it is a breeding ground for germs. This isn't very difficult to manage if you do a little gentle cleaning on a regular basis.
Try using a natural acid such as vinegar instead of commercial cleaners and bleaches when cleaning the bathroom. It will do as good a job but won't pollute the water when washed away.
\BBath and basin\b
Make a paste of bicarbonate of soda and water. Apply with a soft cloth, then wipe off with a moist cloth and rinse. Leave mixture on longer for stubborn stains.
\BMould\b
Wipe vinegar onto affected surfaces. Leave overnight and scrub off the next morning.
\BTiles\b
Use a paste of bicarbonate of soda or a 50/50 mixture of vinegar and water. If you apply a wax polish to your tiles they will be easier to wipe down.
\BToilet\b
To clean the bowl, leave vinegar to soak for about 10 minutes. Limescale can then be easily scrubbed off. Flush toilets were specifically designed for hygiene without chemicals.
\BChemical toilet cleaners\b
Most toilet cleaners are poisonous so store out of reach of children and make sure lids are childproof, just in case. Bleach isn't a cleaning agent, it just bleaches surfaces and materials white. Eventually, it damages chrome, laminates and other plastic material as well as the environment. Use vinegar and lemon juice instead.
Don't mix your chemical cleaners as they can combine to form explosive or toxic gases.
\BDescription:\b A bathroom \I(Webster Publishing)\i
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"Green Cleaning in Your Laundry",39,a4_0014.jpg,c,0
Use pure soap powders in your laundry whenever possible. Avoid phosphate detergents as they pollute water and endanger water plants and wildlife. It's not that important for your clothes to be whiter than white.
If you want to use a commercial washing powder, choose one that is phosphate-free, 100% biodegradable and packaged in paper. Try halving the amount recommended on the packet.
\BPure soap\b
Pure soap or soap flakes do just as good a job as harsh powders or liquid detergents. To make your own washing powder, combine 1 cup of soap flakes with half a cup of washing soda. In soft-water areas, use a greater proportion of soap flakes and in hard-water areas, use more washing soda.
\BDetergent\b
To remove detergent residues from clothes, just add half a cup of washing soda to the machine and prewash. It's important to do this as detergent film may yellow your clothes when mixed with soap.
\BMachine washing\b
Dissolve soap flakes in a little hot water before adding them to the wash.
\BStreaking\b
To prevent streaking in dark cottons and to prolong the life of stretch fabrics, add 125 mL of white vinegar to the rinse cycle.
\BHeavily soiled clothes\b
Use a solution of one and a half tablespoons of washing soda in 250 mL of warm water.
\BSoiled nappies\b
Pre-soak in a solution of one part washing soda to four parts water.
