Impacts of Nitrogen Placement and Inhibitors on Ammonia Volatilization, Nitrous Oxide Emissions and Corn Yields.

Ammonia volatilization, nitrous oxide emissions and nitrate leaching can reduce the amount of inorganic 0nitrogen available for crop production.  The objective was to determine the effectiveness of nitrogen application methods (broadcast, broadcast & incorporated, injected), application timing (preplant versus sidedress) and inhibitors (no inhibitor, urease inhibitor or urease & nitrification inhibitors) on ammonia volatilization, nitrous oxide emissions and crop N uptake and yields on a clay loam soil. Both nitrogen placement and urease inhibitors reduced ammonia volatilization losses.  Nitrous oxide emissions were increased when ammonia volatilization losses were reduced, however the combination of urease and nitrification inhibitors reduced both ammonia and nitrous oxide emissions. Management practices which reduced ammonia volatilization were found to increase crop yields and N uptake.