Rainforest
From Wikipedia, the free encyclopedia.
A rainforest is a forested area with high annual rainfall. Some mention 1000 mm of rain each year as a limit of what is a rainforest, but that definition is far from complete. The soil is poor because of water run-off and the large number of fauna that compete for various minerals. This type of biome is primarily found in tropical climates, although there are a few examples of rainforests in temperate regions as well. As well as prodigious rainfall, many rainforests are characterized by a high number of resident species, and a great biodiversity. It is also estimated that rainforests provide up to 40% of the oxygen currently found in the atmosphere.
The undergrowth in a rainforest is restricted by the lack of sunlight at ground level. This makes it possible for humans and other animals to walk through the forest. If the leaf canopy is destroyed or thinned for any reason, the ground beneath is soon colonised by a dense tangled growth of vines, shrubs and small trees called jungle.
Tropical and temperate rain forests have been subjected to heavy logging and agricultural clearance during the 20th century, and the area covered by rainforest around the world is shrinking rapidly. It is estimated that the rainforest was reduced by about 58,000 km² annually in the 1990s. Rainforests used to cover 14% of the Earth's surface. This percentage is now down to 6% and it is estimated that the remaining rainforests could disappear within 40 years at the present rate of logging. Further estimates suggest that large numbers of species are being driven extinct, possibly more than 50,000 a year due to the removal of their habitat.
The largest rainforests can be found today in the Amazon basin (the Amazon Rainforest), in the inner parts of Democratic Republic of Congo and on Borneo.
- See also: Illegal logging
External links
There are several click to donate sites that have been set up to help protect rainforest and other habitat such as:
Useful Resources For Research