采用静态箱法测定了常规耕作、免耕留低茬低覆盖、免耕留高茬低覆盖、免耕留低茬高覆盖和免耕留高茬高覆盖5个处理条件下燕麦播种前、生育过程中和收割后土壤CO2、CH4和N2O的排放通量.结果表明:CO2排放通量呈单峰曲线变化,峰值出现在苗期;CH4排放通量多为负值,表现为"吸收",季节性变化不明显;N2O排放规律性不明显.处理间相比,CO2排放通量和CH4吸收通量从大到小依次为常规耕作、免耕留低茬低覆盖、免耕留高茬低覆盖、免耕留低茬高覆盖和免耕留高茬高覆盖;N2O与CO2的排放趋势相反;温室气体综合排放效应与CO2趋势一致.免耕留茬秸秆覆盖减少了CO2排放和CH4吸收,增加了N2O排放,温室气体综合排放效应降低,有利于温室气体减排,但不同处理温室气体排放的长期效应还有待研究.%Greenhouse gas emissions (CO2, C-H4 and N2O) under 5 treatments, including conventional tillage, notillage with low stubble and low mulch, no-tillage with high stubble and low mulch, no-tillage with low stubble and high mulch, and no-tillage with high stubble and high mulch, were determined using static gas cases on oat production field before seed sowing, during growth, and after harvest. The results showed: CO2 emission fluxes followed a single peak curve, and the peak appeared at the seedling stage. CH4 fluxes were mostly negative, indicating there was a net absorption. Unobvious trend was observed for N2O emission. Of all the 5 treatments, CH4 and CO2 fluxes were descended in an order of conventional tillage, no-tillage with low stubble and low mulch, no-tillage with high stubble and low mulch, notillage with low stubble and high mulch, and no-tillage with high stubble and high mulch. N2O and CO2 presented an opposite trend in emission. The integrated emission effects of greenhouse gases were similar to CO2. Coverage with stubbles under no-tillage reduced CO2 emission and CH4 absorption, increased N2O emissions, and greenhouse gas emissions were also incrreased. But more studies are still warranted to investigate the long-term effects of the different treatments on greenhouse gas emissions.
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