A new study has revealed that production of biofuel from West Coast forests would increase carbon dioxide emissions from these forests at least 14 percent, if the efficiency of such operations is optimal.
The findings are contrary to assumptions and some previous studies that suggested biofuels from this source would be carbon-neutral or even reduce greenhouse gas emissions.
The study was conducted by scientists from the College of Forestry at Oregon State University and other institutions in Germany and France, and supported by the U.S. Department of Energy.
During the past four years, the study examined 80 forest types in 19 eco-regions in Oregon, Washington and California, ranging from temperate rainforests to semi-arid woodlands.
“On the West Coast, we found that projected forest biomass removal and use for bioenergy in any form will release more carbon dioxide to the atmosphere than current forest management practices,” said Tara Hudiburg, a doctoral candidate at OSU and lead author on the study.
“Most people assume that wood bioenergy will be carbon-neutral, because the forest re-grows and there’s also the chance of protecting forests from carbon emissions due to wildfire.
“However, our research showed that the emissions from these activities proved to be more than the savings,” Hudiburg added.
The only exception to this, the researchers said, was if forests in high fire-risk zones become weakened due to insect outbreaks or drought, which impairs their growth and carbon sequestration, as well as setting the stage for major fires.
It’s possible some thinning for bioenergy production might result in lower emissions in such cases if several specific criteria are met, they said.
The results have been just published in Nature Climate Change.