GREENHOUSE GAS LIFE CYCLE ANALYSIS OF BIOCHAR EFFECTS ON MARGINAL LAND CONVERSION TO SWITCHGRASS PRODUCTION

Producing 36 billion gallons of biofuels by 2022 will require production of biofuel crops on millions of acres not currently devoted to them. In order to avoid competition with food crops, much of the biofuel production may occur on marginal lands. We do not yet know how large-scale conversion of marginal lands to switchgrass production will affect soil C sequestration and greenhouse gas (GHG) emissions and, therefore, we cannot yet anticipate the net effect of the resultant biofuels on GHG emissions. Therefore, we propose to perform life cycle assessments of GHG emissions associated with the conversion to switchgrass production for pyrolytic biofuels on four contrasting marginal soil types. Pyrolysis is an important near-term method for producing Fischer Tropsch liquid biofuels from biomass. Biochar is one of its byproducts. The use of biochar as a soil amendment may reduce the net GHG emissions associated with the biofuels because it can reduce N2O emissions and stably sequester C while improving crop yield, particularly on marginal soils. Another goal, therefore, is to determine the effects of using biochar as a soil amendment on net GHG gas emissions of the biofuels. Finally we will compare the effects of two contrasting methods of biochar application on soil C sequestration and net GHG emissions.