Forests on a fast track forward.

• Author: Hardman, Chris
• Position: !Ojo!

THE DREAM OF A VIRGIN rain forest untouched by the hand of man is merely that--a dream. Scientists warn that even the most remote, old-growth forests are changing as a result of human activities. Veteran researcher William Laurance of the Smithsonian Tropical Research Institute in Panama is part of a team that has analyzed the data from one of the longest running studies of human impacts in the Amazon. What they found is that old-growth forests of central Amazon are experiencing significant changes in dynamics and species composition.

"It's a little scary to realize that seemingly pristine forests can change so quickly and dramatically," Laurance says.

The data come from the Biological Dynamics of Forest Fragments Project (BDFFP), based in Brazil. A joint project between the Smithsonian Institution and the Brazilian Institute for Research in the Amazon, the BDFFP has trained hundreds of scientists and produced more than four hundred publications in the past twenty-five years. Laurance joined the project about nine years ago. One of his tasks has been to analyze the data from sixty-six research plots that span about four hundred square miles of forest reserves north of Manaus. These undisturbed forests house trees more than a thousand years old and have no evidence of logging, large-scale agriculture, or concentrated hunting.

Laurance and his team members began to suspect that something was amiss when their control plots were not acting like control plots. "It's not just that some of the plots we were studying were changing, it's pretty much that all the plots were changing," Laurance explains. "The change is much more than you'd expect from chance alone."

The data show that in the past twenty-five years, almost 90 percent of the trees began growing at an accelerated rate. Further analysis shows that some trees are growing even faster than others. The researchers identified winners--the larger, fast-growing dominant trees like the big canopy trees and the emergents--and losers--the very diverse group of understory trees living in...