27 Jan 2012:
Wide Variety of Threats
Wiping Out World’s Big Trees, Expert Says
A litany of environmental threats, from forest fragmentation and logging to climate change and disease, are wiping out the world’s biggest trees
, according to a published report. In forest ecosystems
worldwide, research shows that giant trees have become particularly vulnerable to a changing environment, ecologist and tropical forest expert William Laurance
writes in New Scientist
magazine. Increased fragmentation has left big trees exposed to stronger winds, while dry conditions and warming temperatures have forced the giants of the forest to consume more energy simply to survive, allowing less energy for growth, Laurance writes. Climate change is also promoting the spread of exotic pathogens, such as Dutch Elm disease, which are devastating native forests. “The decline of big trees foretells a different world where ancient behemoths are replaced by short-lived pioneers and generalists that can grow anywhere, where forests store less carbon and sustain fewer dependent animals, where giant cathedral-like crowns become a thing of the past,” Laurance writes. In addition to providing a critical habitat for wildlife, big trees contribute to local rainfall by transpiring large of amounts of water through their leaves and store abundant amounts of carbon.