Friday, January 16, 2009

Tropical rainforests are regrowing, but impoverished

Environment News Network: The world's tropical rainforests are making a comeback, but young vegetation may not be able to sustain as much diverse wildlife or lock up nearly as much climate-warming carbon dioxide as old trees did, scientists report. The rainforest debate has raged publicly for decades, and more recently has been the subject of behind-the-scenes ferment among conservation scientists. It is the main topic of a Smithsonian symposium on Monday at the Smithsonian National Museum of Natural History in Washington.

These discussions are taking place as the international community is trying to figure out how to stem global warming. Because tropical forests sequester the greenhouse gas carbon dioxide, they are considered an essential part of the solution.

About 135,000 square miles (350,000 square kilometers) of the original forested areas that were cut down by humans are growing back, according to Greg Asner of the Washington-based Carnegie Institution, a presenter at the symposium. That is only 1.7 percent of the original forest. This regrowth is relatively quick, with the shady forest canopy closing in after just 15 years as trees grow taller and denser, offering habitat for creatures adapted to just this environment, such as birds with huge eyes able to see in the leafy gloom...

Tropical rainforest, Fatu Hiva Island, Marquesas Islands, French Polynesia. Shot by Makemake at de.wikipedia, Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2