Submitted to: Proceedings of Great Plains Soil Fertility Conference
Publication Type: Proceedings
Publication Acceptance Date: 3/8/2008
Publication Date: 3/8/2008
Citation: Hatfield, J.L. 2008. The Implications of Biofuel Production on Soil Productivity [CD-ROM]. In: Proceedings of Great Plains Soil Fertility Conference, July 20-23, 2008, Denver, CO.
Technical Abstract: Production of biomass from agricultural crops as a source of energy generated either as a primary or secondary source from agricultural systems has the potential to provide a portion of the nation’s energy needs. Removal of crop residue after harvest is viewed as a major source of cellulosic material; there are challenges that arise with biomass removal in cropping systems in which the crop residue has remained on the soil surface after harvest. The potential impacts of biomass removal on soil productivity and subsequent environmental problems need to be discussed as part of a strategy to improve agricultural production systems. Corn residue is considered one of the largest sources of cellulosic material for energy and may account for over 60% of the biomass production and provides an example for assessing the impacts from other crops. Large amounts of nutrients are removed in corn residue that would have to be incorporated back into the soil and removal of corn residue will lead to decreases in soil organic carbon (SOC). Decreases in SOC reduce water holding capacity and the ability of a plant to extract water during short-term water deficits. Placement of residue on the soil surface protects the surface from water and wind erosion and also moderates the extremes in soil temperature and moisture required for optimal microbial activity. The decline in SOC and extreme microclimate can lead to crusting which limits water infiltration and gas exchange. These have both impact soil productivity and could have subsequent negative impacts on crop production and environmental quality. To avoid long-term environmental and crop production problems a comprehensive assessment of the impacts of biomass removal on the stability of United States crop production systems is needed.