title: Land clearing and the biofuel carbon debt.
abstract: Increasing energy use, climate change, and carbon dioxide (CO2) emissions from fossil fuels make switching to low-carbon fuels a high priority. Biofuels are a potential low-carbon energy source, but whether biofuels offer carbon savings depends on how they are produced. Converting rainforests, peatlands, savannas, or grasslands to produce food crop-based biofuels in Brazil, Southeast Asia, and the United States creates a "biofuel carbon debt" by releasing 17 to 420 times more CO2 than the annual greenhouse gas (GHG) reductions that these biofuels would provide by displacing fossil fuels. In contrast, biofuels made from waste biomass or from biomass grown on degraded and abandoned agricultural lands planted with perennials incur little or no carbon debt and can offer immediate and sustained GHG advantages.
authors.affiliation: The Nature Conservancy, 1101 West River Parkway, Suite 200, Minneapolis, MN 55415, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Fargione
authors.forename: Jason
authors.initials: J
authors.lastname: Hill
authors.forename: David
authors.initials: D
authors.lastname: Tilman
authors.forename: Stephen
authors.initials: S
authors.lastname: Polasky
authors.forename: Peter
authors.initials: P
authors.lastname: Hawthorne
mesh_terms: D018533:Biomass; D001938:Brazil; D002244:Carbon; D002245:Carbon Dioxide / Q000378:metabolism; D018556:Crops, Agricultural; D017753:Ecosystem; D004736:Energy-Generating Resources; D017752:Greenhouse Effect; D007214:Indonesia; D008296:Malaysia; D063245:Plant Development; D010944:Plants / Q000378:metabolism; D012987:Soil; D013997:Time Factors; D014481:United States
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon