Effect of different application time of DCD on methane and nitrous oxide emissions during rice growth period Nitrous oxide emissions affected by tillage measures in winter wheat under a rice-wheat rotation system Soil N2O emission and its agronomic efficiency under different tillage Nitrate loss simulated with DNDC model and control technologies in typical cropland of North China Potential soil N2O emissions and its controlling factors under different land use patterns on hilly-gully loess plateau Effects of adding DCD on N2O emissions in soil cracking