Turning native ecosystems into "farms" for biofuel crops causes major carbon
emissions that worsen the global warming that biofuels are meant to mitigate,
according to a new study by the University of Minnesota and the Nature
The carbon lost by converting rainforests, peatlands, savannas, or grasslands
outweighs the carbon savings from biofuels. Such conversions for corn or
sugarcane (ethanol), or palms or soybeans (biodiesel) release 17 to 420 times
more carbon than the annual savings from replacing fossil fuels, the researchers
said. The carbon, which is stored in the original plants and soil, is released
as carbon dioxide, a process that may take decades. This "carbon debt" must be
paid before the biofuels produced on the land can begin to lower greenhouse gas
levels and ameliorate global warming.
The conversion of peatlands for palm oil plantations in Indonesia ran up the
greatest carbon debt, one ...