沼泽湿地CO2、CH4、N2O排放对氮输入的响应

利用静态暗箱-气象色谱法，选取小叶章沼泽化草甸进行野外原位试验，研究氮输入对沼泽湿地CO2、CH4和N2O等3种温室气体排放的影响,结果表明：氮输入对沼泽湿地CO2和CH4排放有明显影响，其季节排放总量分别是对照处理的1.3和2.5倍，但对CO2和CH4的季节变化模式无明显影响；氮输入对N2O的排放强度和季节变化模式均有显著影响,CO2排放通量与5cm深土壤温度存在显著的正相关关系，与地表温度和1.5m气温存在指数关系，而CH4和N2O排放与温度之间没有显著的相关性．在20、100和500年时间尺度上氮输入处理的CH4和N2O全球增温潜势（GWP）分别比对照处理增加了150％、150％和80％，表明氮输入在长、短时间尺度上都是增强CH4和N2O的温室效应的。

CO2,CH4 and N2O emissions to the atmosphere upon nitrogen addition in the swamp wetland

By using the static opaque chamber-GC techniques, the influence of nitrogen addition in situ on emissions of CO_2, CH_4 and N_2O from Doyeuxia angustifolia wetland was studied. The results showed that there were no significant differences in patterns of seasonal variations of CO_2 and CH_4 among the treatments, but the CO_2 and CH_4 emission with nitrogen addition treatment increased 30% and 150% respectively compared to the control treatment. However, both the seasonal pattern and emissions of the N_2O were significantly affected by the nitrogen addition. The CO_2 flux increased with the increase of the temperature, and there was no significant statistical correlation between the CH_4 flux and temperature, so is the N_2O. On long time scale of 20, 100, and 500-year period, the integrated global warming potential (GWP) of CH_4+N_2O released during the growing season for the treatments of nitrogen addition was 150%, 150% and 80%, respectively, higher than that for the control treatment, which suggested that the nitrogen addition could enhance the GWP of the CH_4 and N_2O either in long time or short time scale.