The Epic Interactive Encyclopedia 1997/The_Epic_Interactive_Encyclopedia_97.iso/a/amazon/infotext

Text File | 1992-09-02 | 2KB | 42 lines

South American river, the world's second
longest, 6,570 km/4,080 mi, and the largest
in volume of water. Its main headstreams, the
Marañón and the Ucayali, rise in central Peru
and unite to flow E across Brazil for about
4,000 km/2,500 mi. It has 48,280 km/30,000 mi
of navigable waterways, draining 7,000,000 sq
km/2,750,000 sq mi, nearly half the South
American landmass. It reaches the Atlantic on
the equator, its estuary 80 km/50 mi wide,
discharging a volume of water so immense that
64 km/40 mi out to sea, fresh water remains
at the surface. The Amazon basin covers 7.5
million sq km/3 million sq mi, of which 5
million sq km/2 million sq mi is tropical
forest containing 30% of all known plant and
animal species (80,000 known species of
trees, 3,000 known species of land
vertebrates, 2,000 freshwater fish). It is
the wettest region on Earth; average rainfall
2.54 m/8.3 ft a year.
The opening up of the Amazon river basin to
settlers from the overpopulated east coast
has resulted in a massive burning of tropical
forest to create both arable and pasture
land. The problems of soil erosion, the
disappearance of potentially useful plant and
animal species, and the possible impact of
large-scale forest clearance on global
warming of the atmosphere have become
environmental issues of international
concern.
Brazil, with one third of the world's
remaining tropical rainforest, has 55,000
species of flowering plant, half of which are
only found in Brazilian Amazonia. In June
1990 the Brazilian Satellite Research
Institute announced that 8% of the rainforest
in the area had been destroyed by
deforestation, amounting to 404,000 sq
km/155,944 sq mi (nearly the size of Sweden).