为了探讨减少稻田氨挥发的合理水氮管理措施,基于田间试验资料,分析了不同水氮管理稻田氧挥发损失规律及其交互影响,并用DNDC(土壤碳氮循环模型)模型模拟了节水灌溉条件下不同氮肥管理稻田氨挥发损失动态特征.结果表明,控制灌溉和实地氮肥管理的联合应用既大幅降低了稻田氨挥发峰值,又降低了稻田大部分无施肥时段的氨挥发损失,稻田氨挥发损失量为39.63 kg/hm2,较常规水肥管理稻田降低44.69％.采用DNDC模型模拟节水灌溉条件下不同氮肥管理稻田氨挥发损失量是可行的,稻季氨挥发总量模拟值与实测值相对误差均在±10％以内.节水灌溉和实地氮肥管理的水氮联合调控显著降低了稻田氨挥发损失量,且实地氮肥管理对氨挥发损失降低的贡献率要大于节水灌溉.该文研究结果可为稻田的水肥科学管理,减少稻田氨挥发损失提供依据.%In order to investigate the reasonable water and nitrogen management for reducing ammonia volatilization from paddy field, the effects of ammonia volatilization from paddy field under different water and nitrogen managements were analyzed based on field experiments. In addition, ammonia volatilization from paddy fields with different nitrogen managements under controlled irrigation was simulated. The results showed that joint application of controlled irrigation and site-specific nitrogen managements not only substantially reduced the peak values of ammonia volatilization from paddy fields, but also lowered the ammonia volatilization in the most time of rice growing stage without nitrogen fertilizer input. Nitrogen loss through ammonia volatilization from paddy fields with the joint application of controlled irrigation and site-specific nitrogen management was 39.63 kg/hm2, decreased by 44.69% compared to traditional water and nitrogen management. The processes of ammonia volatilization with different nitrogen managements under controlled irrigation can basically captured by DNDC model. The errors of simulated values and measured values of ammonia volatilization during rice growing stage were less than ±0%. Joint application of controlled irrigation and site-specific nitrogen management significantly reduced nitrogen loss through ammonia volatilization from paddy field. And the contribution of site-specific nitrogen management to the reduction of ammonia volatilization from paddy fields was larger than controlled irrigation. The study results can provide a basis for scientific management of water and nitrogen and reduction of ammonia volatilization from paddy fields.
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