猪粪沼液施用对稻麦轮作系统土壤氧化亚氮排放的影响

以典型的猪粪尿发酵沼液为对象,探讨了沼液施入量和管理方式对以中国东部稻麦轮作农田系统土壤N2O排放规律和排放量的影响。研究结果表明,与化学氮肥相比,沼液施用未影响稻麦轮作系统土壤N2O排放的季节变化规律,但影响其排放量的大小。稻季100%施用沼液的处理（N100%DPS）其累积排放量为0.71kg·hm-（22008年）和1.38kg·hm-（22009年）,显著高于100%施用化肥的处理（N100%Ure）a,即0.68kg·hm-2和1.06kg·hm-2。麦季N100%DPS处理N2O的累积排放量分别为6.56kg·hm-（22008年）和5.05kg·hm-2（2009年）,与N100%Urea处理（2008年：5.89kg·hm-2;2009年：3.93kg·hm-2）无显著差异,但均显著高于稻季各处理。随着沼液替代化学肥料用量的降低,稻田N2O排放量呈降低趋势,而沼液一次性施入和分次施入对稻田N2O排放的季节动态和累积排放量均无显著影响;但沼液不同的管理方式对麦季累积N2O排放量更为复杂。稻、麦两季N100%DPS处理中N2O排放系数（f）均最大,分别达到0.3%和1.6%,但沼液分次施入和一次性施入的处理间f值均无显著差异。

Influence of Application of Digested Pig Slurry on Nitrous Oxide Emission Under Rice-Wheat Rotation System

The effect of digested manure slurry on soil nitrous oxide（N2O） emission applying as fertilizer remains ambiguous. This study was conducted to determine how application of digested pig slurry（DPS） would affect N2O flux dynamics and accumulative emission in rice-wheat rotation system. Results showed that（1）Application of DPS had no significant influence on N2O emission dynamics during the growing periods of rice and winter wheat; （2）The accumulative N2O emission was 0.71 kg·hm-2 and 1.38 kg·hm-2, respectively, during the growing periods of rice in 2008 and 2009, which were significantly higher than those in N100%Urea treatments; （3）The N2O flux and its accumulative emission in N100%DPS treatments was from 5 to 972 μg·m-2·h-1, and from 5.05 kg·hm-2 to 6.56 kg·hm-2, respectively, which were not significantly different than those in N100%Urea treatments; （4）N2O emissions were declined with the substitution rates during the growing period of rice, while the trends were opposite; （5）N2O emission factor was the highest in N100%DPS treatment, reached to 0.3% in rice field and 1.6% in wheat field; （6）The application frequency of DPS had no significant effect on accumulative N2O emissions in rice field; while ON75%DPSN75%DPS（P0.05 in 2008） and N50%DPS ON50%DPS（P0.01 in 2009） in wheat field.