不同氮肥管理方式对华北粮田N2O排放和作物产量的影响分析

Effects of Different Nitrogen Management Methods on Soil N_2O Emission and Crop Yield of Grain Field in North China

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N_2O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N_2O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N_2O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N_2O总排放量为0.31 kg·hm^(-2),籽粒产量6 200 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N_2O总排放量1.70 kg·hm^(-2),籽粒产量9 000 kg·hm-2以上。

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 N20 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 N20 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 N20 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 N20 total emission was 1.70 kg. hm-2 and maize grain yield exceeded 9 000 kg.hm-2.