贝加尔针茅草原生态系统生长季碳通量及其影响因素分析

Variation of net ecosystem carbon flux and its impact factors on Stipa baicalensis steppe in the growing season

以贝加尔针茅草原为研究对象,利用涡度相关通量测量系统,测定CO2通量及其影响因子。结果表明,贝加尔针茅草原CO2通量存在明显的日、季变化,不同生育阶段CO2通量日、季变化呈"U"型,其中以7月最为明显,CO2通量固碳、释放碳最大值均出现在7月,分别为-0.56和0.83mg/(m2.s)。潜热通量、显热通量、有效光合辐射与CO2通量显著相关,与土壤温度、土壤含水量相关不显著。

CO2 flux and its impact factors were measured by an eddy correction system in Stipa grassland.There were distinct diurnal and seasonal variations with an inverted U-shape diurnal change in CO2 flux.There was obvious change in July,and the maximum uptake and emission were-0.56 and 0.83 mg/（m2·s）,respectively.Latent heat flux,sensible heat flux,net radiation flux and photosynthetic active radiation were related to CO2 flux.There was no obvious correlation between soil temperature and soil water content with CO2 flux.