BEIJING, April 24 (Xinhuanet) -- Mountain pine beetles that are destroying forests along much of the Rocky Mountain range are doing so much damage that they may affect climate change, Canadian researchers reported on Wednesday.

    The damage is nearly equivalent to the polluting effects of forest fires, they reported in the journal Nature.

    "In the worst year, the impacts resulting from the beetle outbreak in British Columbia were equivalent to 75 percent of the average annual direct forest fire emissions from all of Canada during 1959-1999," Werner Kurz of the Canadian Forest Service in Victoria, British Columbia and colleagues wrote.

    Usually, a forest is a carbon "sink," soaking up carbondioxide that would otherwise affect the atmosphere and help hold in heat.

    The beetle, namely Dendroctonus ponderosae, changed that. Dead trees release carbon as they rot, and of course fail to use carbon dioxide as they would if alive.

    The beetles lay eggs under the bark of lodge-pole pine and jack-pine trees, eventually killing them. Once beetles infest a tree, it cannot be saved.

    They have destroyed 50,000 square miles (130,000 square kilometers) of forest in western Canada alone. Hundreds of thousands of square miles have also been damaged in the United States.

    (Agencies)