Submitted to: Soil Science Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 15, 2006
Publication Date: September 26, 2006
Citation: Stott, D.E., Smith, D.R., Bucholtz, D.L. 2006. Trace gas emissions from corn-soybean rotations on a Mollisol. Soil Science Society of America Annual Meeting, November 12-16, 2006, Indianapolis, IN. 2006 CDROM. Technical Abstract: Sustained productivity and environmental quality in the future will require improved quantification of management effects on carbon and nitrogen dynamics. Changes in management can convert agriculture from a net source to a net sink of greenhouse gases. Two study sites, one on a Typic Haplaquoll and one on a Mollic Hapludalf were established in 2003, to determine the impact of nitrogen management on trace gas emissions in the Eastern Corn Belt of the US. There were five treatments for a corn (Zea mays)-soybean (Glycine max) rotation implemented: 1) Conventional tillage (spring chisel/fall disk) with N fertilizer applied as urea ammonium nitrate (UAN) before planting corn; 2) No-till with UAN applied planting corn; 3) No-till with UAN fertilizer applied in a split application to corn, ½ before planting and ½ post-emergence (~ 2 weeks following emergence); 4) No-till with winter rye as a cover crop each year and UAN applied before planting corn; and 5) Nu-tillage (modified no-till using a nu-till planter), with all UAN applied before planting corn. For all treatments, herbicides were applied in the appropriate manner for each treatment, according to common practices. There are four replications of each treatment laid out in a complete randomized block design. Both the corn and soybean phases of the rotations are planted each year. Beginning in 2004, gas emissions are measured weekly in all plots during the growing season. Each year, corn plots are sampled twice a week from just before fertilizer application until four to six weeks later, when an increase in N2O is usually seen. Fluxes of CO2, N2O, and CH4 are measured using the static rectangular chambers. Gas samples are analyzed with a GC equipped with TCD, TS, and FID detectors.