不同氮肥管理方式对华北粮田2排放和作物产量的影响分析

通过华北小麦和玉米田已发表文献分析，明确不同施氮量、氮肥基追比及氮素调控措施对土壤N2O排放和作物产量的影响。结果表明：高氮水平下减少氮肥用量并调整基追比有助于减少土壤N2O排放；添加硝化抑制剂双氰胺（DCD）对小麦和玉米产量的提高和土壤N2O的减排效果均较好。兼顾华北粮田N2O减排和作物产量，小麦季推荐合理施氮量167~174 kg·hm-2，基追比1：1，添加DCD，土壤N2O总排放量为0.31 kg·hm-2，籽粒产量6200 kg·hm-2以上；玉米季推荐合理施氮量177~181 kg·hm-2，基追比2：3~1：2，添加DCD，土壤N2O总排放量1.70 kg·hm-2，籽粒产量9000 kg·hm-2以上。

Effects of Different Nitrogen Management Methods on Soil N2O Emission and Crop Yield of Grain Field in North China

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-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 167~174 kg·hm-2 at basal/top dressing ratio 1:1 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-cation rate of 177~181 kg·hm-2 at basal/top dressing ratios 2:3~1:2 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.