ARS | Publication request: Effects of land use change from grassland and wheat to switchgrass in the Southern Great Plains

Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: September 8, 2009
Publication Date: December 14, 2009
Citation: Billesbach, D.P., Torn, M.S., Bradford, J.A., Gunter, S.A., Fisher, M.L., Zou, C. Effects of land use change from grassland and wheat to switchgrass in the Southern Great Plains. American Geophysical Union Fall Meeting. San Francisco, CA 14-18 December 2009. (Abstract)

Technical Abstract: We have begun an inter-agency, interdisciplinary experiment to observe and quantify some of the effects of the conversion of wheat and pasture lands in northwestern Oklahoma to switchgrass (Panicum virgatum L.) production. Switchgrass is a candidate crop for the production of cellulosic ethanol, and is believed to hold several advantages over corn. Through this experiment, we will observe and quantify some of these projected advantages such as apparent water use. Other perceived advantages for switchgrass are the minimal management techniques required and the simple fact that it is not a food grain. The former comes from the fact that modern switchgrass varieties are annual grasses, derived from native prairie species and are well suited for their environment. The latter advantage is further enhanced by the fact that switchgrass can be successfully cultivated on land that is unsuitable or is marginal for other crops. Our experiment is located on fields owned by the USDA-ARS Southern Plains Range Research Station in Woodward, OK. One field was an established grassland pasture and the other a marginal wheat field. Both have been or are in the process of being converted to switchgrass production. Both fields have been instrumented with identical eddy covariance towers for the measurement of CO2, water, and energy fluxes, along with associated atmospheric and soil parameters. We have also begun a comprehensive set of biometric and soil measurements. In 2010, the former grassland site will also be extensively instrumented with soil moisture sensors and gauge blocks to explore the effects that this land use conversion will have on stream flow and groundwater recharge.