Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: November 3, 2009
Publication Date: November 3, 2009
Citation: Nyakatawa, E.Z., Mays, D., Way, T.R., Watts, D.B., Torbert III, H.A. 2009. Carbon dioxide emissions in conventional and no-till corn production systems under different fertilizer management practices. American Society of Agronomy Meetings. CDROM. Technical Abstract: Soil management practices such as tillage and fertilizer application methods affect soil emissions of greenhouse gases which impacts agricultural contributions of greenhouse gases. It is important to develop and evaluate strategies for reducing soil emissions of greenhouse gases such as carbon dioxide (CO2) under conventional and conservation tillage. This study investigated soil CO2 fluxes in a corn (Zea mays L.) field receiving poultry litter (PL) and ammonium nitrate (AN) fertilizers under conventional tillage (CT) and no-till (NT) systems using surface (SA), soil incorporation (SI), or subsurface band (BA) fertilizer application methods on a Decatur silt loam soil in north Alabama. Soil gas samples were collected using custom built static chambers and analyzed for CO2 concentrations using a GC for calculating soil gas fluxes. All treatments in the study were net emitters of CO2. The highest soil CO2 flux of 22.8 mg m^-2 min^-1 was observed in CT plots with soil incorporation of PL (CT-PL-SI) followed by surface application of PL in CT and NT systems and surface application of AN in NT plots, which had net soil CO2 fluxes of about 9 mg m^-2 min^-1. Carbon dioxide fluxes from plots under subsurface band application of PL in CT and NT systems were similar to that from a grass fallow control plot, around 5 mg m^-1 min^-1. This study shows that soil incorporation of PL under CT poses the highest potential to increase agricultural contributions of CO2 greenhouse gases.