The Amazon Rainforest
The Amazon is a rainforest in South America.
It encompasses 1.2 billion acres (7 million km²), with parts located
within nine nations: Brazil (with 60% of the rainforest), Colombia,
Peru, Venezuela, Ecuador, Bolivia, Guyana, Suriname and French Guiana.
This forest represents over half of the planet's remaining rainforests.
States or departments in four nations bear the name Amazonas for the
Amazon.
The region is home to ~2.5 million insect species, tens
of thousands of plants, and some 2000 birds and mammals. The diversity
of plant species is the highest on earth with some experts estimating
that one square kilometre may contain over 75,000 types of trees
and 150,000 species of higher plants. One square kilometre of Amazon
rainforest can contain about 90,000 tons of living plants. This
constitutes the largest collection of living plants and animal species
in the world. One in five of all the birds in the world live in the
rainforests of the Amazon. To date, an estimated 438,000 species of
plants of economic and social interest have been registered in the
region with many more remaining to be discovered or cataloged. (Note:
Brazil has one of the most advanced laws to avoid biopiracy, but
enforcing it is a problem.)
There has been concern among environmentalists for many
years, regarding the deforestation of the region, stemming mainly from
the fact that more than one fifth of the Amazon Rainforest has already
been destroyed; and much more is threatened. Not only are
environmentalists concerned about the loss of biodiversity which will
result from the forest's destruction, they are also concerned about the
release of the carbon which is held within the trees -- this carbon will
accelerate global warming.
The deforestation of this area in the 1980s was largely
considered catastrophic. Yet, in 1996, the Amazon was reported to have
shown a 34 per cent increase in deforestation since 1992. A new report
by a congressional committee says the Amazon is vanishing at a rate of
52,000 square kilometers (20,000 miles²) a year, over three times the
rate for which the last official figures were reported, in 1994.
Environmentalists commonly stress the fact that there is not only a biological incentive to protecting the rainforest,
but also an economic one. One square kilometer in the Peruvian Amazon
has been calculated to have a value of $682,000 if intact forest is
sustainably harvested for fruits, latex, and timber; $100,000 if
clear-cut for commercial timber (not sustainably harvested); or $14,800
if used as cattle pasture.
The Força Aérea Brasileira has been using EMBRAER R-99
surveillance aircraft, as part of the SIVAM program, in an attempt to
halt rainforest molestation. At a conference in July 2004, scientists
warned that the rainforest will no longer be able to absorb the millions
of tons of greenhouse gases annually, as it usually does, because of
the increased pace of rainforest destruction.
The large-scale cutting of trees begins a cycle in which farmers burn
leftover jungle scrub to replenish the soil, which releases huge amounts
of carbon dioxide (200 to 300 million tons in 2003) into the
atmosphere, that are in turn absorbed by the rainforest.
9,169 square miles of rain forest were cut down in 2003 alone.
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