Submitted to: Natural Resources Research Update (NRRU)
Publication Type: Research Technical Update
Publication Acceptance Date: 10/24/2008
Publication Date: 3/5/2009
Publication URL: http://hdl.handle.net/10113/14703
Citation: Varvel, G.E. 2009. Cropping systems with corn residue production levels sufficient to maintain or even improve soil organic carbon levels and allow partial removal for biofuel production. Natural Resources Research Update (NRRU). Update #238677. Available at: http://hdl.handle.net/10113/14703 and http://hdl.handle.net/10113/18315. Interpretive Summary:
Technical Abstract: Increasing energy demands and prices, declining petroleum reserves, and political instability in oil-rich areas of the world, all call for greater use of domestically produced biofuels. Recent reports concluded that US agriculture and forest lands have the capacity to produce immense amounts of plant material needed for domestically produced biofuels. One of these materials, corn stover, was presented as a major feedstock available for biofuel production that could supply as much as 25% of the estimated feedstock needed by 2030, but can it be utilized sustainably. In a long-term high yielding irrigated environment in the western Corn Belt identified as one possible location where corn stover may be utilized, soil organic carbon levels were at or above initial levels in continuous corn, continuous soybean, and soybean-corn cropping systems after 14 years. In these systems, residue production was greater than 2.7 tons per acre in all systems, a level of residue production at or above that cited throughout the literature as the amount required for maintaining current soil organic carbon levels in many cropping systems. These results suggest that a portion of corn stover could be harvested for biofuel production without reducing soil organic carbon levels in similar high yielding systems. Publications contributing to the NRRU Release as shown above: Varvel, G.E., and W.W. Wilhelm. 2008. Soil carbon levels in irrigated western Corn Belt rotations. Agronomy Journal 100:1180-1184. Wilhelm, W.W., J.M-F. Johnson, D.L. Karlen, and D.T. Lightle. 2007. Corn stover to sustain soil organic carbon further constrains biomass supply. Agronomy Journal 99:1665-1667. 2007.