Greenhouse Gas Footprints of Single Species Non-Legume Cover Crops Following Winter Wheat.

Agriculture practices can affect the production of greenhouse gas emissions. Conflicting studies on the ability of cover crops to alter carbon and nitrogen (N) storage, reduce nitrogen losses and improve crop yields necessitate further study. One understudied loss mechanism is gasses losses of carbon and nitrogen. The objective of this study was to measure CO₂, N₂O, and CH₄ gas emissions from summer and winter non-legume cover crop and chemical fallow treatments planted after wheat. Field plots where established in 2007 at the Kansas State University Experiment Station in Riley County, Kansas to examine the use of different cover crops in a Soybean -Wheat/Cover Crop-Sorghum rotation, with a range of nitrogen fertilizer application rates applied at sorghum planting. Gas flux measurements were measured weekly from polyvinyl chloride (PVC) chambers constructed according to USDA-ARS GRACEnet Project Protocols. Two PVC rings 30-cm diameter 15-cm tall were installed in each plot to a depth of 10-cm, and used to support soil chambers during measurements. Flux measurements were taken by placing vented chambers on rings and collecting samples at 0, 15, 30, 45 min. Linear regression techniques were used to determine flux rates for each chamber and average flux rates for each treatment were used to calculate total season fluxes.