In 1980, Ronald Reagan got a lot of flak when he implied that plants were a cause of air pollution. But the former President now may have some scientific support for his claim. For the last decade, Walter Oechel, a San Diego State University biology professor, has been leading a team of scientists measuring gases absorbed and released by trees and plants in Alaska. Oechel's findings could send environmentalists reeling.
According to Oechel, the vegetation in the northern Alaskan tundra is now emitting, rather than storing, carbon dioxide--the gas responsible for global warming. Historically, Arctic soil has collected carbon dioxide; now, due to the greenhouse effect, many regions are warmer, lowering the water table and accelerating soil decomposition. Photosynthesis cannot keep up and the vegetation winds up conducting CO2 as well as producing oxygen. But don't blame it on the trees and plants. "We caused this by putting so much carbon into the atmosphere in the first place," Oechel says.