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通过室内培养试验，研究了不同水分含量下水稻土的 Ｎ２Ｏ排放，结果表明，在水分含量相当于田间持水量时，土壤具有最大的 Ｎ２Ｏ排放速率，当水分含量在田间持水量之上时，反硝化作用是Ｎ２Ｏ的主要来源。水分含量在田间持水量之下时，尽管硝化作用强烈，但Ｎ２Ｏ排放量较小。通过温室盆栽试验研究了不同水分管理措施下，水稻土Ｎ２Ｏ和ＣＨ４的排放，同常规水分管理方式相比，长期淹水显著增加了ＣＨ４的排放而减少了Ｎ２Ｏ的排放。相反，湿润灌溉的处理在整个水稻生长期内没有明显的 ＣＨ４排放，但其Ｎ２Ｏ排放对水分状况敏感，出现数次峰值，从而总排放量远高于其它两处理。
The results showed that the soil had the highest N2O emission rate when the water content was equivalent to the field water holding capacity. When the moisture content was above the field capacity, the reverse Nitrification is the main source of N2O. When moisture content is below field capacity, N2O emissions are small despite strong nitrification. The greenhouse pot experiment was conducted to study the emission of N2O and CH4 from paddy soils under different water management practices. Compared with conventional water management, long-term flooding significantly increased CH4 emissions and reduced N2O emissions under different water management practices. In contrast, wet irrigation did not have significant CH4 emissions throughout the rice growth period, but its N2O emissions were sensitive to the water conditions with several spikes, resulting in much higher total emissions than the other two treatments.