Tuesday, November 03, 2009
Valuable but endangered: the Amazon basin
Not all of the big plant and animal that live in the Amazon Basin are known because of its huge unexplored areas. No one knows how many species of fish there are in the river.
Wet tropical forests are the most species-rich biome, and tropical forests in the Americas are consistently more species rich than the wet forests in Africa and Asia.
As the largest tract of tropical rainforest in the Americas, the Amazonian rainforests have unparalleled biodiversity. One in ten known species in the world live in the Amazon Rainforest. This constitutes the largest collection of living plants and animal species in the world.
The region is home to about 2.5 million insect species, tens of thousands of plants, and some 2,000 birds and mammals. To date, at least 40,000 plant species, 3,000 fish, 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region.
One in five of all the birds in the world live in the rainforests of the Amazon. Scientists have described between 96,660 and 128,843 invertebrate species in Brazil alone.
The diversity of plant species is the highest on Earth with some experts estimating that one square kilometer may contain over 75,000 types of trees and 150,000 species of higher plants.
In many regions, the forest has been cleared for soy bean plantations and ranching (the most extensive non-forest use of the land) and some of the inhabitants harvest wild rubber latex and Brazil nuts. This is a form of extractive farms, where the trees are not cut down, and thus this is a relatively sustainable human impact.