Nov. 5 (Bloomberg) -- Deforestation’s relative contribution to global carbon emissions has declined as pollution from fossil fuels increased, according to a researcher at the faculty of earth and life sciences at VU University in Amsterdam.

The removal of trees that can absorb carbon dioxide may now account for around 12 percent of global carbon emissions from human activities, according to a study led by Guido van der Werf and published in the academic journal Nature Geoscience.

While forest destruction still causes “high emissions,” the “perspective has changed,” van der Werf said by telephone. “Carbon emissions from fossil fuel combustion have increased substantially” the article in Nature Geoscience said. That makes “the relative contribution from deforestation and forest degradation even smaller.”

The Intergovernmental Panel on Climate Change estimated in 2007 that deforestation was responsible for 20 percent of greenhouse gas blamed for global warming. Almost 200 nations that will meet next month in Copenhagen have yet to agree on what role forests should play in a climate treaty intended to extend or replace the 1997 Kyoto Protocol.

Van der Werf’s study could potentially allay concerns about an oversupply of forest credits in carbon markets. The study reflected a lower deforestation rate than the Intergovernmental Panel due to more detailed satellite imagery showing tree coverage.

His research also said that “notable” CO2 is released by the destruction of peatlands, areas of partially decaying vegetation that covers around 2 percent of the world’s surface. Peatland destruction is responsible for 3 percent of human induced CO2 emissions and should be included in Copenhagen negotiations, the report said.

“Negotiations should strive to be as inclusive as possible,” Van der Werf said. Carbon dioxide produced by destroying both peatlands and forests may account for around 15 percent of total carbon emissions, the study concluded.

To contact the reporter on this story: Catherine Airlie in London at cairlie@bloomberg.net

Last Updated: November 4, 2009 19:00 EST