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Conservationists have been struggling for years to slow deforestation in the Amazon basin. Earlier this year the Brazilian government said those efforts were paying off. Satellite surveys showed a lot less clear-cutting last year than in the past. Well, a new study shows that those surveys missed a major problem. NPR's John Nielsen explains.
JOHN NIELSEN reporting:
Scientists have been using satellite photographs to track clear-cut logging in the Amazon for more than 20 years now. The photos show huge chunks of forest being eaten up by settlements, ranches and farms. It doesn't look like there's much going on in the middle of these forests, but scientist Greg Asner says that's not what you see when you're on the ground. What you see instead are lots of narrow roads built by small-time loggers, he says. The roads lead to isolated clearings.
Mr. GREG ASNER (Carnegie Institution): ...where they can park the trucks, go into the forests, cut down particular trees and literally drag them out to that one clearing.
NIELSEN: These loggers are hunting for trees like mahogany, rosewood and other species that command high prices at sawmills, trees that are sometimes more than 200 feet tall with trunks the size of houses. Not too long ago these kinds of selective logging operations were thought to be a good thing for the Amazon, or at least a better thing than the clear-cuts that took out every tree. But Asner, a remote sensing expert at the Carnegie Institution in California, says these trees do a lot of damage when they fall.
Mr. ASNER: Because a lot of the trees are connected by vines in these types of forests, it tends to pull down a lot of the understory trees and the young trees. And you end up with this pile of debris in the bottom on the forest floor.
NIELSEN: Asner says this damage isn't obvious on traditional satellite photos. Even when you can see the gaps in the forest canopy, it's hard to tell if they are natural; sometimes trees just fall. But Asner also says he's figured out a way to tell when loggers are involved. Working with other scientists from the Carnegie Institution and the United States Forest Service, he combined photographs with temperature and light readings, and then, using software he spent nine years perfecting, Asner started looking for the telltale signs of small-scale logging operations--for example, tangled lines surrounding a hole in the canopy.
Mr. ASNER: As if you threw spaghetti down on a plate. And those would be the kind of trails and networks that are underneath the canopy that are used by loggers to pull those logs out. And we call those skid trails.
NIELSEN: Asner and his team scanned the entire Amazon for these spaghettilike skid trails. He says he found them almost everywhere. When his team added up the damage, they found that an area the size of Connecticut was being damaged every year. And that could be just the beginning. Frank Merry is an economist with the Amazon Institute for Environmental Research in the Brazilian state of Para. He says hunters, miners and farmers tend to follow the logging roads into the forests.
Mr. FRANK MERRY (Amazon Institute for Environmental Research): And that then allows conversion to another land use or just continued degradation through the entry of fire.
NIELSEN: Regulating small-time loggers has been next to impossible in the past. But Asner says he wants to help with that by giving a simplified version of his satellite tracking system to Brazil's forestry agencies. `Good idea,' says Merry.
Mr. MERRY: Any information that those agencies have to make their jobs easier would be tremendously valuable.
NIELSEN: There are some rays of hope in this new study. For example, Asner's findings hint that the selective logging problem may be peaking, partly because the most highly prized trees are now so far from the major sawmills that it's impossible to find a tree, cut it down, drag it out and still make a profit. John Nielsen, NPR News, Washington.
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