稳定性氮肥配合秸秆还田对水稻产量及N2O和CH4排放的影响

以中国科学院辽宁沈阳农田生态系统国家野外科学观测研究站连续两年的试验平台为依托,以潮棕壤为供试土壤,开展了稳定性氮肥配合秸秆还田对水稻产量及N₂O和CH₄排放的影响研究,设置对照(CK)、尿素(U)、尿素+脲酶抑制剂+硝化抑制剂(U+I)、秸秆还田(S)、秸秆还田+尿素(S+U)、秸秆还田+尿素+脲酶抑制剂+硝化抑制剂(S+U+I)6个处理.结果表明: 与CK相比,尿素显著提高了水稻产量、N₂O和CH₄累积排放及全球增温潜势.硝化抑制剂和脲酶抑制剂与尿素配施可显著减缓N₂O的累积排放.秸秆还田显著增加了N₂O和CH₄累积排放、全球增温潜势和温室气体排放强度.S+U+I处理水稻产量最高,但温室气体排放强度也显著高于其他处理;U+I处理产量略低于S+U+I,但温室气体排放强度最小.秸秆单独还田处理作物产量与对照相比无显著差异.在东北潮棕壤发育的水田中,S+U+I和U+I是相对较优的施肥模式.

Effects of stabilized N fertilizer combined with straw returning on rice yield and emission of N2O and CH4 in a paddy field

Based on a two-year field experiment located at Shenyang Applied Ecological Experiment Station of Chinese Academy of Sciences, we examined the effects of stabilized N fertilizer combined with straw returning on rice yield and emission of N₂O and CH₄ in aquic brown soil. Six treatments were set up, i.e. control (CK), urea(U), urea+urease inhibitor+nitrification inhibitor (U+I), straw (S), straw+urea (S+U), straw+urea+ urease inhibitor+nitrification inhibitor (S+U+I). The results showed that urea application increased rice yield, cumulative N₂O and CH₄ emission, and global warming potential. The treatment of U+I significantly mitigated cumulative N₂O emission. Returning rice straw to the field significantly increased cumulative N₂O emission, cumulative CH₄ emission, global warming potential, and greenhouse gas emission intensity. The S+U+I treatment had the highest rice yield and greenhouse gas emission intensity. U+I treatment had the the second highest rice yield and the lowest greenhouse gas emission intensity. Rice yield in the S treatment showed no significant difference with CK. Our results indicated that S+U+I and U+I are relatively better agricultural strategies compared with other treatments in paddy fields on aquic soil.