沼泽湿地N2O通量特征及N2O与CO2排放间的关系

对三江平原淡水沼泽湿地进行了连续4年的野外原位观测.结果表明,沼泽湿地冬季是N2O的汇,但从全年来看,仍为N2O排放的源.5～8月是N2O排放的主要时期.土壤温度是影响N2O通量季节变化的重要环境因素,生长季内的积水水位和土壤温度则会影响到N2O通量的年际变化;沼泽湿地N2O与CO2排放间相关性显著,促使二者间产生这种内在联系的因素包括温度、植物根系的作用、有机质分解的联系作用以及植物气孔行为的调节.

Characteristics of N2O flux and the relationship between N2O and CO2 emission in the marsh wetland

Through 4 years continuous field original place observation in the freshwater marsh wetland of Sanjiang Plain, the results showd that marsh wetland was N2O source in winter; but from the view of while year, it was still the source of N2O emission. The main period of N2O emission was from May to August. Soil temperature was the important environmental factor affecting the seasonal variation of N2O flux. Water level and soil temperature during the growing season would affect the interannual variation of N2O flux. The correlation between N2O and CO2 emission in marsh wetland was marked, and the factors that led to the internal relation including temperature, plant roots, correlation action of decomposition of organic matter and the adjustment of stomatal behavior of plant.