Integrating reduced nitrogen fertilization with a nitrification inhibitor under drip fertigation increases maize nitrogen use efficiency while reducing carbon footprint

This study aimed to determine whether reduced N application combined with the nitrification inhibitor dicyandiamide (DCD) could maintain maize yield, increase nitrogen use efficiency (NUE), and reduce environmental costs under drip fertigation. In a two-year spring maize field experiment, compared with conventional farmer N application (CF), a reduction of 20% in N application (80%CF) did not reduce maize yield, NUE, or economic returns. The 80%CF plus DCD treatment, compared with 80%CF, increased maize yield, NUE, and net income. It reduced cumulative N 2 O emissions, greenhouse gas intensity, and carbon footprint relative to the other treatments. Combining a 20% N reduction with DCD under drip fertigation can maintain maize productivity, increase N utilization, regulate soil N transformation, reduce environmental costs, and increase ecological and economic benefits