【摘要】 2002年6月到10月在三江平原利用静态暗箱-气相色谱法对不同土壤水分状况或积水深度的毛果苔草沼泽、小叶章草甸以及灌丛进行了CH4排放的测定,结果为毛果苔草沼泽CH4排放通量(11.9mg/m2.h)>小叶章草甸(8.5mg/m2.h)>灌丛(0.75mg/m2.h),差异达到高度显著水平(α=0.01),主要是由土壤水分状况不同而造成的。由于生境的差异,3种湿地类型CH4排放通量的季节变化形式也不尽相同。温度、土壤Eh和毛果苔草生物量是影响CH4排放的重要因素,湿地CH4排放通量和箱内外温度或不同深度的地温均呈显著或极显著正相关,小叶章草甸和毛果苔草沼泽分别与10cm及15cm的Eh呈极显著负相关(P<0.01),毛果苔草生物量和CH4排放通量呈显著正相关(P<0.05)。更多还原

【Abstract】 CH₄ emission fluxes were measured in the Sanjiang Plain by static opaque chamber-GC technique during June to October in 2002. According to soil moisture and water table position, three sits were selected including Carex lasiocarpa marsh, Calamagrostis angustifolia meadow and shrub. The results indicated that CH₄ flux was Carex lasiocarpa marsh （11.9 mg/m²·h）> Calamagrostis angustifolia meadow （8.5 mg/m²·h）> shrub （（0.75） mg/m²·h）, the difference of CH₄ fluxes among the three sites was markedly （α=0.01）. This difference was mainly caused by soil moisture. Because of differences of environment, the seasonal variation in methane emission from the three wetland ecosystems were not same. Temperature, Eh and plant were important factors influencing CH₄ emission. There were positive relationships between CH₄ fluxes and temperatures. In Calamagrostis angustifolia meadow and Carex lasiocarpa marsh, CH₄ fluxes were negatively correlated with 10 cm and 15 cm soil Eh values respectively. And in Carex lasiocarpa marsh CH₄ flux was positively correlated with plant biomass.更多还原