Nitrogen fertilization but not soil tillage affects nitrous oxide emissions from a clay loam soil under a maize–soybean rotation

Denitrification of nitrate fertilizer has been shown to contribute to agricultural nitrous oxide (N2O) emissions. Previous studies have revealed that no-till practices have insignificant or negative impact on nitrogen volatilization of nitrate fertilizers. This study examined the difference in N2O emissions according to tillage practice (mouldboard plough and no-tillage) and mineral nitrogen application rates (0, 80, 160 kg nitrogen per hectare) in a maize-soybean rotation from 2004-2005 in a well-drained humic gleysol. Results indicated that tillage had no effect on nitrogen volatilization rates and denitrification increased linearly with application rate. These results support prior studies’ findings that no-till practices do not impact N2O emissions related to agriculture.