<正>采用密闭箱动态测量法对三江平原小叶章典型湿地土壤CO2通量进行了研究。结果表明,小叶章湿地土壤CO2通量有明显的季节变化和日变化,并且呈现出一定的规律性。7～10月,土壤CO2通量呈现出季节变化的单峰模式。在1d的观测期间,土壤CO2通量从早晨开始增大,到午后达到极大值,后逐渐降低到第2天凌晨达极小值,然后又开始增加。研究同时表明小叶章湿地土壤CO2通量的主要影响因素为地温(相关系数为0.7699)。而因湿地环境土壤水分充足,土壤含水量对土壤CO2通量的影响不明显,当土壤水分不成为限制因素时,土壤CO2通量与土壤温度呈正相关。根据测量结果,小叶章湿地土壤CO2通量在整个测量期间的变化范围为0.208～1.265g/(m2·h),平均水平为0.619g/(m2·h)。

In many temperatezone ecosystems,seasonal changes in environmental and biological factors influence the dynamics and magnitude of soil surfaceatmosphere exchange.Research was conducted to measure soilsurface fluxes of CO2 in Deyeuxia angustifolia dominated wetland during the growing seasons in the Sanjiang Plain of Northeast China.Data were collected between July and October 2001.Soilsurface CO2 fluxes were measured with a closedchamber system.This study was carried out to find out the seasonal fluctuation and daily change in soilsurface CO2 fluxes from Deyeuxia angustifolia wetlands as well as to investigate the edaphic factors controlling the CO2 fluxes.The results revealed that there were both seasonal fluctuations and daily change in CO2 fluxes.The ranges of measured soilsurface CO2 flux were 0.208～1.265 g/(m2·h).Soilsurface CO2 fluxes were 0.619 g/(m2·h)in average level.Study of several edaphic factors like soil temperature and soil moisture of Deyeuxia angustifolia wetland showed that the fluxtemperature relationships are evident exponent correlation(the correlation coefficient is 0.769 9).