【摘要】 为研究秸秆还田对热带地区稻田N₂O排放的影响,以不同管理措施下耕作4 a的稻田土壤为基础,通过盆栽试验观察种植水稻后N₂O排放动态变化。试验设置了不施氮对照（CK）、常规施氮（CT）、单施秸秆（ST）和常规施氮+秸秆（CTST）处理。结果表明,各处理N₂O排放通量在-0.23～6.64 mg/（m²·h）,主要集中在水稻生育前中期,CTST处理相比于CT处理显著降低了分蘖肥期田面水无机氮浓度（P<0.05）,同时减少了N₂O排峰的维持时间;各处理全生育期N₂O累积排放量为0.13～2.85 g/m²,施氮处理显著高于不施氮处理（P<0.05）,ST处理与CK处理差异不显著（P>0.05）,CTST处理相比于CT处理可减排49.11%（P<0.05）。因此,施用氮肥是N₂O排放增加的主要原因,秸秆还田可显著减少热带土壤-水稻种植系统N₂O排放。更多还原

【Abstract】 In order to study the effects of straw returning on N₂O emission from paddy fields in tropical areas, this study was based on paddy soil cultivated for 4 years under different management measures, and observed the dynamic changes of N₂O emission after rice planting through pot experiment. The experiment set up N free control（CK）,conventional N application（CT）,only straw application（ST）and conventional N application combined with straw（CTST）treatment. The results showed that N₂O fluxes ranged from-0.23 to 6.64 mg/（m²·h）,mainly concentrated in the early and middle stages of rice growth. Compared with CT treatment, CTST treatment, significantly reduced inorganic N concentration in surface water at tillering stages（P<0.05）,and reduced the maintenance time of N₂O emission peak. The whole growth period N₂O cumulative emission of each treatment ranged from 0.13 to 2.85 g/m²,and the N application treatment was significantly higher than the N free treatment（P<0.05）,and there was no significant difference between the ST and CK treatment（P>0.05）. Compared with the CT treatment, the CTST treatment could significantly reduce the N₂O emission by 49.11%（P<0.05）. Therefore, application of nitrogen fertilizer is the main reason for the increase of N₂O emission, and straw returning can significantly reduce N₂O emission in tropical soil-rice system.更多还原