Effects of Different Nitrogen Management Methods on Soil N 2 O Emission and Crop Yield of Grain Field in North China

Effects of Different Nitrogen Management Methods on Soil N2O Emission and Crop Yield of Grain Field in North China SHU Xiao-xiao1, WANG Yan-qun1, LI Ying-chun2, PENG Zheng-ping1*, WEI Shan-shan1, SHI Xin-li1, ZHAO Yan-wei1 (1.College of Resources and Environmental Sciences/Key Laboratory for Farmland Eco -Environment of Hebei, Agricultural University of Hebei, Baoding 071001, China;2.Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China) Abstract: Through the published literature analysis of wheat and maize field in North China, this study investigated the effects of different management methods of nitrogen(N)application rates, basal/topdressing ratios and N control measures on the soil N2O emission and crop yield. The results showed that reducing N application rates and adjusting basal/top dressing ratios under high N level could decrease soil N2O emissions. Besides, N application with nitrification inhibitor dicyandiamide(DCD)was an effective practice for wheat/maize yield enhance原 ment and soil N2O emission reduction. In order to reduce the soil N2O emission as well as ensure crop yield production in North China, the optimal N application rate of 167耀174 kg·hm-2 at basal/top dressing ratio 1颐1 with DCD was recommended for wheat production. As a result, soil N2O total emission was 0.31 kg·hm-2 and wheat grain yield reached more than 6 200 kg·hm-2. For maize production, the optimal N appli原 cation rate of 177耀181 kg·hm-2 at basal/top dressing ratios 2颐3耀1颐2 with DCD was regarded as the best practice. Soil N2O total emission was 1.70 kg·hm-2 and maize grain yield exceeded 9 000 kg·hm-2.