稻田温室气体排放的原位观测研究

his study was carried out in the conventional paddy fields (rice-winter wheat rotations), CH4 and N2O fluxes were simultaneously measured using static opaque chamber-gas chromatograph (GC) method. The main objectives of this study were to gain an insight into CH4 and N2O emission intensity, emission characteristics, driving mechanism, and their net global warming potential (GWP) in rice paddies. Results have shown: Different levels of nitrogen fertilizer can not alter annual emission patterns of CH4 and N2O in the paddy fields. Substantial CH4 emissions from the rice fields were mainly during the rice growing season, while N2O emissions were mostly during the following non-rice season (including following fallow period and wheat season). Increasing amount of nitrogen fertilizer can reduce the annual CH4 emission, but remarkably increase the annual N2O emission and their net GWP did not differ significantly over a 100-year horizon.