Forests in the northern hemisphere could begrowing faster now than they were 200 years ago as a result of climatechange, according to a study of trees in eastern America.
The trees appear to have accelerated growth rates due to longer growingseasons and higher concentrations of carbon dioxide in the atmosphere.Scientists have documented the changes to the growth of 55 plots ofmixed hardwood forest over a period of 22 years, and have concludedthat they are probably growing faster now than they have done at anytime in the past 225 years – the age of the oldest trees in the study.
GeoffreyParker, a forest ecologist at the Smithsonian Environmental ResearchCentre in Edgewater, Maryland, said that the increase in the rate ofgrowth was unexpected and might be matched to the higher temperaturesand longer growing seasons documented in the region. The growth mayalso be influenced by the significant increase in atmospheric carbondioxide, he
said
Trees across North America are growing at an unprecedented rate as a result of higher temperatures and CO2 levels
apakah nie kesan positif terhadap climate change 
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Post time 2-2-2010 05:07 PM
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