Research On Methane Flux Of Poplar Plantation In Peatland Of Yangtze River

Forest soil is the largest sink of air methane among the terrestrial ecosystems,while thenatrual wetland is the most important source of methane. The poplar plantation in the peatlandof Yangtze River possesses double attributes, so the function of methane sink&source iscomplicated and unknown. This study was carried out in the poplar plantation in the peatlandin Junshan, Yueyang City. This research is to discover the methane flux and its influencingfactors. First, during the clearcut of the matural plantation(Apr., May, Jun.), a contrastobservation,based on the static chamber–FMA approach, of methane flux in clearcut field anduncut field to discover the effects of clearcut to methane flux. Then after the clearcut, EddyCovariance Method was used to observe methane flux of study eara in the Non-growingseasons (Oct., Nov., Dec., Jan., Feb.). The following results were obtained：(1)Study field is the sink of methane in fast growing seasons, and the rate of methaneuptaking was0.11⁰.90mg m^-2 d^-1. However in the Non-growing seasons, it's the source ofmethane, and the rate of methane releasing was0.91³.67mg m^-2 d^-1.(2) No obvious diurnal variation regulation was observed neither in growing seasons norin non-growing seasons. But seasonal variation regulation was observed in both growingseasons and non-growing seasons.(3) In growing season, methane flux was related to soil temperature, SWC and vegetations.But in non-growing season, it was only related to latent heat flux.(4) The static chamber–FMA approach performace well in this research. And this ClosePath and Open Path EC system are available in CO₂,H₂O,CH₄observation. However, theuncertainty of the results when the methane flux is weak should be further discussed.