ARS | Publication request: GREENHOUSE GAS EMISSIONS FROM VARYING TILLAGE PRACTICES UNDER CORN-SOYBEAN ROTATIONS

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: April 30, 2004
Publication Date: October 31, 2004
Citation: Stott, D.E., Smith, D.R., Bucholtz, D.L. 2004. Greenhouse gas emissions from varying tillage practices under corn-soybean rotations. Soil Science Society of America Annual Meeting. 2004 CDROM.

Technical Abstract: Soil agroecosystems can be a source or sink of greenhouse gases. Our objective was to monitor greenhouse gas emissions from newly established management systems for a corn-soybean rotation. The practices, all with pre-plant fertilizer except where noted, were conventional chisel/disk, no-till, no-till with winter rye cover crop, no-till with split fertilizer, and precision tillage. Treatments were replicated four times, with one set of treatments per crop. Plots were located at two sites in northwestern Indiana, one on a Mollisol and one on an Alfisol. Gas samples were obtained with the use of rectangular, aluminum flux chambers. Gas samples were analyzed with a GC fitted with a thermal conductivity detector, electron capture detector, and a flame ionization detector in tandem, for determining the concentrations of CO2, N2O, and CH4, respectively, and fluxes were calculated. During the first growing season, the N2O, and CH4 emissions were negligible. CO2 fluxes were significantly greater in the soybean than in the corn. Fluxes in the corn increased slightly after planting, and then gradually decrease over the growing season, while fluxes from the soybean plots continued to increase throughout the growing season. Emissions were slightly greater on the Mollisol than on the Alfisol. Choice of crop had a greater impact in CO2 reductions than did the soil management system. [GRACEnet Publication]