ARS | Publication request: Fertilizer Source Impacts on Nitrous and Nitric Oxide Emissions in Corn Cropping Systems of the Upper Midwest U.S.

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2010
Publication Date: October 31, 2010
Citation: Venterea, R.T. 2010. Fertilizer Source Impacts on Nitrous and Nitric Oxide Emissions in Corn Cropping Systems of the Upper Midwest U.S. [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. Paper No. 174.

Technical Abstract: It is well-established that the application of nitrogen fertilizer to soil results in emissions of nitric oxide (NO) and nitrous oxide (N2O), which are gases that have important local, regional, and global air quality impacts. Despite hundreds of studies reporting measurements of NO and N2O emissions from agricultural soils, there are relatively few guidelines for managing fertilizer nitrogen to reduce these emissions while maintaining optimum levels of crop production. We have been conducting plot-scale research for the past several years in Minnesota corn/soybean and potato cropping systems to determine if the selection of a fertilizer source or application strategy has reliable impacts on NO and N2O emissions. This presentation will discuss our most important findings. Our studies have shown that conventionally applied anhydrous ammonia tends to generate higher N2O emissions, but lower NO emissions, compared with conventional, spring-applied (CU) urea in these cropping systems. We have found some reduction in N2O emissions using polymer-coated urea compared with CU, although not consistently. Our studies in no-till managed systems suggest that N2O emissions can be minimized by placing fertilizers below the biologically robust surface soil layer.