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When the burning season strikes, life and health in the Amazon falter, and color drains out of the riotous green landscape as great swaths of majestic trees, creeping vines, delicate bromeliads and hardy ferns are reduced to blackened stubble. But more than just the land, these annual blazes also lay waste to a cherished notion that has roosted in the popular mind for decades: the idea of the rain forest as the "lungs of the world."
Ever since saving the Amazon became a fashionable cause in the 1980s, championed by Madonna, Sting and other celebrities, the jungle has consistently been likened to an enormous recycling plant that slurps up carbon dioxide and pumps out oxygen for us all to breathe, from Los Angeles to London to Lusaka. Think again, scientists say.
Far from cleaning up the atmosphere, the Amazon is now a major source for pollution. Rampant burning and deforestation, mostly at the hands of illegal loggers and of ranchers, release hundreds of millions of tons of carbon dioxide into the skies each year. Brazil now ranks as one of the world's leading producers of greenhouse gases, thanks in large part to the Amazon, the source for up to two-thirds of the country's emissions.
"It's not the lungs of the world," said Daniel Nepstad, an American ecologist who has studied the Amazon for 20 years. "It's probably burning up more oxygen now than it's producing."
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http://www.latimes.com/news/printedition/front/la-fg-amazon8jun08,1,2048059.story?coll=la-headlines-frontpage