保护性耕作对温室效应的影响

农业是非常重要的温室气体排放源，而不合理的农田管理措施强化了农田排放源的特征，同时弱化了吸收汇的作用。保护性耕作对温室效应的影响来自两方面，一方面是免耕减少了农田CO2排放，对CH4和N2O排放的影响不明确；另一方面是秸秆还田以后部分秸秆C以气体形式释放进入大气，增加了农田CO2、CH4排放，但秸秆还田相对其他用途提高了土壤固碳潜力，减少了总的温室气体排放量。通过耕作与秸秆管理对温室气体排放资料的整理分析，指明保护性耕作是一种有利于减少温室效应的农田管理措施，为保护性耕作的温室效应研究提供借鉴。

Influence of conservation tillage on greenhouse effect

Agriculture is an important source of greenhouse gas emissions. Unreasonable agricultural management increases greenhouse gas emissions and decreases soil absorbed greenhouse gas. The influence of conservation tillage on greenhouse effect comes from two aspects: one is that no tillage can reduce CO2 emission, but the CH4 and N2O emissions are uncertain; the other is that some straw C can release gas into atmosphere and increase greenhouse gas emission, but straw returning can improve carbon sequestration potential and so reduce the total greenhouse gas emissions. Through analyzing the data about soil tillage and straw management on greenhouse gas emission, the research results prove that conservation tillage can reduce greenhouse effect, and can also provide some references for researching agricultural greenhouse effect.