The Wonder of Wetlands

February/March 1998

WHAT IS A WETLAND?
Wetlands range from springs, seeps, mires and bogs in the mountains to midland marshes and floodplains, to coastal lakes, mangrove swamps and estuaries. Estuaries rate with rainforests and coral reefs as the planet's most prolific habitats, supporting a range of species far greater than other environments. A rich variety of plants, birds, fish, crabs, prawns and many smaller creatures live together in a close-knit community of interdependent relationships.

WHAT SERVICES DO WETLANDS RENDER?
The primary task of wetlands is to manage water - they hold water back during floods and release it during dry periods. In a dry country like South Africa, this is crucial. By regulating water flow during floods, wetlands reduce flood damage and help prevent soil erosion. Wetlands also remove pollutants from water and some serve as breeding grounds for fish. All support biodiversity and many form part of game parks which attract tourists.

PUTTING A PRICE ON WETLANDS
Nature, one of the world's most respected scientific journals, recently reported that worldwide, wetlands are worth US$4.9-trillion per year (about R25-trillion). In its May 1997 issue, Nature said the estimated value of the world's ecosystem services and natural capital is $33-trillion (about R165-trillion). This is 1.8 times the global Gross Domestic Product. The services of ecological systems and natural capital stocks are critical to the functioning of the Earth's life support system, says Nature. Without life support, economies would not exist. Thus natural capital is part of the total economic value on the planet. Almost 40% of the estimated value of terrestrial systems comes from wetlands (or 14% of the total value for terrestrial and marine systems).

BREAKDOWN OF WETLAND SERVICE VALUES
"Wetlands are crucial to the national economy," says David Lindley, co-ordinator of the Rennies Wetland Project. "A conservative, preliminary estimate shows that wetlands earn/save the South African economy nearly R26,85-billion a year in disease prevention and tourism enhancement, as well as an additional R21-billion saved in drought and flood damage, conserved in fertilisers and top soil, and earned by our fisheries." South Africa's real gross domestic product was R295,6-billion. Thus wetlands made a contribution equal to nearly 10% of the GDP.

MANAGING WATER
In 1988, after a series of droughts and floods, the Government's subsidy bill was R14 000-million, according to South African Environments into the 21st Century, by Huntley, Siegfried and Sunter (1989, Tafelberg). This could have been drastically reduced had natural wetlands been functioning at peak capacity.

Flood attenuation - In Wisconsin in the USA it has been shown that water catchment zones with 15% of their area composed of wetlands have flood peaks 65% lower than those without them. Wetlands on the Charles River in Massachusetts have been preserved as natural flood defences because it was cheaper than building an artificial flood defence scheme. The flood prevention value was thus $13 500 per hectare.

Soil erosion prevention - According to Huntley et al, South Africa's annual soil loss is 400 million tonnes. If the plant nutrients such as nitrogen, potassium and phosphorous carried out to sea by our rivers each year were to be entirely replaced by commercial fertilisers, the cost would exceed R2 536-million in today's figures. Yet wetlands stop soil and nutrients flowing out to sea. Soil is easily lost but hard to replace. The mean rate of soil formation is less than 0.1 tonne per hectare, per year. Almost three million hectares have been rendered unusable due to dongas and sheet erosion, say Huntley et al. This is valued at a permanent loss of R3 886-million, not including the loss of natural fertilisers above.

WHY IS SA WETLAND MANAGEMENT A MESS?
David Lindley believes it is because South Africa has neither a national wetland policy nor wetland Act and the large majority of South Africans are ignorant of the crucial importance of wetlands. In addition, no high-ranking policitians have championed the cause, as was done in America. To make matters worse, there is hardly anyone working full-time in hands-on wetland conservation, outside declared reserves. Mpumalanga Parks Board is the only provincial conservation body to have such a person. Wetland legislation in South Africa is also not enforced. A single Act, and relevant, enforceable regulations, are essential for wetland protection. The Act and regulations need to enhance wise use as well.

A RAY OF HOPE
The only national initiative is the Rennies Wetland Project, under the auspices of the Wildlife and Environment Society of SA and WWF-SA. Its sponsors are Rennies, Mazda Wildlife Fund and SA Breweries. The project has launched its second phase of operation, educating people about the value of wetlands and teaching wetland users about sustainability. It has published a series of booklets called "Wetland Fix" to show how wetlands can be managed and rehabilitated - simply and cost-effectively.

The Rennies Wetland Project has a small professional staff consisting of a national co-ordinator, ecologist David Lindley, and a part-time administrative assistant, Gayle Barichievy. David works mainly with volunteers in the field (professional agriculturists, nature conservation extension officers or members of the public). He has formed a number of wetlands working groups around the country whose task it is to identify, list and assess the condition of key wetlands in their area. The wetland working groups will also promote management of wetlands using the "Wetland Fix" series.
For more information, fax: (011) 486 3369.

PURIFYING WATER TO PREVENT DANGEROUS WATERBORNE DISEASES
According to the Water Reseach Commission, at least 650 South Africans, most of them children, die of diarrhoea every day. Short-term direct medical costs are around R5-billion a year. Total annual direct hospital costs are estimated at R15-billion - equivalent to South Africa's 3% annual economic growth rate. Wetlands help purify water and can reduce this cost.

WHAT IS REQUIRED?
David Lindley says South Africa needs to:

• Develop a holistic South African Wetlands Conservation Act.
• Develop capacity to police the Act.
• Carry out a national wetland inventory: without the basic knowledge of where South Africa's wetlands are and what their ecological and economic importance is, it is impossible for wetland conservation to be efficiently directed.
• Monitor wetland losses and gains. It is speculated that at least 50% of South Africa's wetlands have been lost.
• Develop a comprehensive manual covering rehabilitation options.
• Develop a standard wetland delineation manual.
• Initiate a national wetland conservation programme involving all relevant government departments, wetland owners and the public.

Nitrates and phosphates
An environment rich in wetlands can reduce the potentially harmful impact of artificial fertilisers on the environment. Recent estimates from Sweden conclude that a wetland area of 2km² could reduce the amount of nitrogen leaking into adjacent waters by nearly 2 000 tonnes a year (Wetlands and their Values: Contributor, E Maltby). The value of this service may be as much as $200 000 per hectare (about R1-million). If we calculate that, for argument's sake, spending rands in SA is roughly equivalent to spending dollars in America, and South Africa has 16,6 million hectares of arable land, then the land times the R200 000 per hectare would give us a saving of R3,2-trillion a year if the wetlands on our farms were restored or maintained.

DROUGHT MITIGATION AND GROUNDWATER RECHARGE
In Gauteng, a sizeable portion of the costs of receiving potable water come from the Lesotho Highlands levy. If Gauteng were using its water more efficiently and conserving wetlands, this cost might never have been incurred (around R20 000 a day).

BIODIVERSITY AND TOURISM
According to Satour, the earnings from tourism are R12,5-billion a year. Most tourists come to enjoy our wild animals and areas.

FISHERIES
The latest available value of the national fishing catch (1994) was about R500-million. In today's money, that would probably be R731-million. And three quarters of the fish we eat depend on estuaries for their life-cycle - a great incentive to protect our estuaries.

SOME COMPANIES CARE ABOUT WETLANDS
While Mondi is not always a knight in shining green armour, one cannot fault the timber and paper conglomerate for its wetland rehabilitation projects. The Siyaya estuary and catchment near Mtunzini in northern KwaZulu-Natal were badly affected by soil erosion and poorly-managed farming during the 1950's. The riverine forests, swamp forests and papyrus swamps were severely depleted, wetlands were drained and the catchment area's ability to hold water was radically reduced. Vast amounts of silt were deposited into the ecologically important Siyaya estuary, completely changing its character and adversely affecting the marine organisms that used it as a nursery area.

Mondi Forests bought the land in the 1980's and registered the 50ha Twinstreams area, the core of the Siyaya catchment, as the 100th site in the SA Natural Heritage Programme. A unique catchment rehabilitation programme was begun by botanist Ian Garland. He made sure that more than 40 000 indigenous trees were planted in the catchment which have significantly reduced erosion. The velocity of water flow is now slowed by the massive root systems of the forest trees, papyrus and palms. Silt-free water enters the Siyaya estuary which has cleared and deepened it. Sixteen fish species have now returned to the estuary. A Mondi environmental education centre has been built at Twinstreams where children can learn about the importance of conserving ecosystems. Mondi has also reclaimed the Hlatikulu Vlei near Giants Castle. This is a priority wetland in Natal - as identified by George Begg - but was modified by ridging and draining. This was a common fate of wetlands in an attempt by landowners to "make the land more productive". Drained wetlands lost their natural functions as flood-buffers and silt traps and could no longer support wetland species such as wattled cranes. Mondi bought the farm Tierhoek in the late 80's and formed a joint venture with the Crane Foundation. A breeding sanctuary has been established on the wetland. Mondi provided the funding for blocking the many drains and constructing three large, shallow dams to reestablish the wetland.

February/March 1998

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