Effects Of Moisture On Greenhouse Gas Emission Of Different Microhabitats Soil In Zoige Wetland

In order to test the effects of moisture on microhabitats (inside tussock, outside tussock, foot of hill and hillside) soil greenhouse gas emission of Zoige wetland and its mechanism, we carried out this research. Through field sampling and incubation experiment, we simulated wet treatment, dry treatment and drying-rewetting cycles to find the differences of greenhouse gas emission and soil physical and chemical properties of different microhabitats. Study showed that, (1) SOC pool of microhabitats were significantly different, it’s:inside tussock>outside tussock>foot of hill>hillside. (2) Both soil moisture content and microhabitat type had significante influence on greenhouse gas emission. Dry treatment reduced the greenhouse gas emission, while the drying-rewetting cycles promoted the CH4 and N2O emission, reduced the CO2 emission of outside tussock, foot of hill and hillside. The inside tussock microhabitat released the most CO2 and the outside tussock took the second place, while with wet treatment and drying-rewetting cycles, the inside tussock microhabitat released the least N2O among four microhabitats, but the most with dry treatment. (3) Both DOC and MBC contents were significantly influenced by microhabitats, they were much higher inside tussock and outside tussock, while only DOC was significantly influenced by moisture, soil with drying-rewetting cycles increased faster than others. (4) With the same moisture, the inside tussock microhabitat produced the most CO2 equivalent emission and for the same microhabitat, the highest equivalent occured in drying-rewetting cycles, and the dry treatment was the lowest. (5) Cumulative CO2 emission equivalent was significantly positive correlated with DOC, MBC, NO3--N, NH4+-N; CH4 emission was negative correlated with NO3--N, while N2O didn’t show any correlation with others. Greenhouse gas emission of soil is affected by comprehensive effects of multiple factors, in order to further explore the contribution of tuccock microhabitan on greenhouse gas emission, we should strengthen the field experiment in situ investigation to know more about the mechanism of greengouse gas emission, then provid reference to the Zoige wetland soil source or sink of greenhouse gases under climate change.