|Del Grosso, Steven - COLORADO STATE UNIV.|
|Parton, William - COLORADO STATE UNIV.|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 20, 2004
Publication Date: November 4, 2004
Citation: Adler, P.R., Del Grosso, S.J., Parton, W.J. 2004. Modeling greenhouse gas emissions from bioenergy cropping systems using daycent[abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. 5886 Interpretive Summary: An Interpretive Summary is not required.
Technical Abstract: Reducing the net global warming potential (GWP) of energy use is a major factor driving interest in biofuels. The main components of GWP from crop production are N2O emissions, soil CO2 fluxes, CO2-C emissions associated with agricultural inputs and farm equipment operation, and CH4 fluxes. Bioenergy cropping systems vary in contribution to the net greenhouse gas (GHG) production due to the crop yield and resulting quantity of fossil fuels displaced, quantity and quality of C added to the soil, N2O emissions, N use efficiency, and inputs required for production and operation of farm machinery. The objective of the study was to use DAYCENT to model the net GHG emissions of bioenergy cropping systems (corn, soybeans, alfalfa, switchgrass, and hybrid poplar) in Pennsylvania for inclusion in a full C cycle analysis. System C (soil plus root C) was the largest GHG sink. Crops with higher soil C inputs, such as switchgrass and hybrid poplar, had higher equilibrium soil C levels. Displaced gasoline, a function of crop yield and ethanol conversion efficiency, was the second largest GHG sink. However, it will be the largest long term GHG sink, as the soil C levels reach equilibrium. Switchgrass had higher Nuse efficiency and lower N2O emissions. Reducing inputs through reducing tillage and N fertilizer applications can significantly reduce net GHG emissions.