Deforestation threatens Amazon river,
scientists warn
Friday, July 30, 2004, By
Vivian Sequera, Associated Press
BRASILIA, Brazil — Deforestation has
provoked drastic changes along many Amazon tributaries and scientists
warned it was only a matter of time before it affects the main trunk of
the river.
A four-year study on the effects of
deforestation found many of the Amazon's 7,000 tributaries were drying up,
while fertilizers and pesticides have profoundly altered their ecosystems.
"So far this hasn't affected the Amazon
river ... and we don't want to get to that point," Alex Krutsche, a
biologist at the University of Sao Paulo who was involved in the study,
said Thursday.
Although the Amazon rain forest has lost as
much as 20 percent of its original forest cover — some 6 million square
kilometers (2.3 million square miles) — Krutsche said little environmental
damage was apparent along the main trunk of the 6,800-kilometer-long
(4,223-mile-long) river.
The forest is being cut down at an ever
faster pace to make way for cattle ranching — and more recently, large
grain plantations, especially soybeans which require lots of fertilizers
and strong pesticides to flourish in the equatorial region.
"For now it's speculation to say whether
the Amazon will disappear or not," said Reynaldo Victoria, a University of
Sao Paulo researcher, who added that the smallest tributaries are among
the most affected. "To save them we only have to follow the law."
To keep the river from drying up, Brazilian
law requires that farmers not disrupt the forest within 50 meters (165
feet) of any river bank.
Another law limits clear cutting to only 20
percent of the forest property — though the remaining 80 percent can be
logged selectively with a government-approved forestry management plan.
But these and other tough environmental
laws are routinely flouted in the massive Amazon region that covers an
area larger than Europe. The government has few environmental inspectors
in the rain forest.
The results were presented at the final day
of the third conference on the Large Scale Biosphere-Atmosphere Experiment
in Amazonia.
The experiment, which began in 1998 and is
expected to continue through 2006, studies the interaction between the
Amazon rain forest, the world's largest remaining tropical wilderness, and
regional and global weather patterns.
It involves more than 1,000 scientists and
specialists from over 100 research institutions including NASA, and is
being called the largest international environment research project ever.
Source:
Environmental News Network |