Meanwhile, about 17 percent of the Brazilian Amazon has been deforested since the opening of the basin to development in the mid-1960s, he said.
Critics warn the Amazon is close to a tipping point in which the continued stripping of forests will stem rainfall and turn the tropical region into scrubland. Because trees pull moisture from the ground and release it back into the atmosphere, leading to rainfall, cutting them down threatens this "vegetative recycling" process, Walker said.
Walker and fellow researchers from Brazil and the United States conducted three years of atmospheric computer modeling on the region. Their study assumed the worst-case scenario – that all of the Brazilian Amazon not protected by the government would be deforested.
Even under this scenario, their findings indicate rainfall levels would not decrease to the point of changing the landscape and harming the ecosystems within the protected areas.
"Some people think the tipping point is going to occur at 30 percent to 40 percent deforestation," Walker said. "Our results suggest this is not the case; that you can have quite a bit of deforestation – perhaps up to 60 percent – before you get to the crash point."
The study also assumes the government-protected forests would not be altered beyond their current condition.
Robert Walker, professor of geography at Michigan State University, discusses his research into Brazil's policy of protecting the Amazon rainforest.
(Photo Credit: Michigan State University)
A study by Robert Walker, professor of geography at Michigan State University, contends that Brazil's policy of protecting the Amazon is working, contrary to common belief.
(Photo Credit: Michigan State University)
Source: Michigan State University