Tillage and Fertilizer Application Methods Effects on Greenhouse Gas Flux (CO2, CH4 and N2O)

Tillage and fertilization practices used in row crop production are thought to alter greenhouse gas emissions from soil. Thus, a field experiment was conducted at the Sand Mountain Research Station located in the Appalachian Plateau region of Northeast Alabama on a Hartsells fine sandy loam. Measurements of CO2, CH4, and N2O emissions were evaluated using GRACEnet protocols to assess the effects of different tillage (convention vs. no-till) and fertilizer application (banding vs. surface application) practices in a corn cropping system. Fertilizer sources consisted of urea-ammonium nitrate (UAN), ammonium nitrate (AN) and poultry litter (PL) applied at a rate of 170 kg ha-1 of available N. Surface application of fertilizers resulted in the greatest concentration of gaseous loss compared to banding of fertilizers. Conventional tillage practices also resulted in higher concentrations of gas emissions compared to no-tillage practices. These results suggest that banding fertilizers in no-tillage systems minimizes greenhouse gas emissions; and thus increase retention of soil nutrient including C and N that can be utilized by agronomic crops.