论文部分内容阅读
利用LI-8100土壤CO2排放通量全自动测量系统,于2010年1—4月测定了艾比湖地区不同植被类型样地的土壤呼吸速率,结合环境因子、冻土厚度及室内土壤理化性质分析,探讨了温带干旱区季节性冻土厚度变化对土壤呼吸的影响。结果表明:土壤温度在冻结期是影响冻土厚度的最主要环境因子,而解冻期冻土厚度变化与土壤温度等环境因子关系不显著(P>0.05);冻土厚度在不同时期影响土壤呼吸速率的程度不同,冻结期两者呈显著正相关(R2=0.782,P<0.05),解冻初期两者呈弱相关(P>0.05);土壤呼吸速率在土壤冻结期与解冻初期不存在显著差异(P>0.05),但在解冻完全期则表现出明显的增加趋势(差值为0.14—0.37μmol·m-2·s-1),表明冻土融化会明显地增加土壤碳排放,从而增加大气中的CO2。结果阐明了艾比湖地区季节性冻土厚度变化对土壤呼吸的影响,为揭示全球变暖背景下冻土退化过程中的碳释放机理提供理论基础。
Using the LI-8100 soil CO2 emission flux automatic measurement system, the soil respiration rate of different vegetation types in the Aibi Lake area was measured from January to April in 2010. According to the analysis of environmental factors, the thickness of frozen soil and the physical and chemical properties of indoor soil The effects of seasonal frozen soil thickness changes on soil respiration in temperate arid regions were discussed. The results show that the soil temperature is the most important environmental factor affecting the thickness of frozen soil during the freezing period, while the variation of frozen soil thickness during thawing period has no significant relationship with environmental factors such as soil temperature (P> 0.05). The thickness of frozen soil affects soil respiration (R2 = 0.782, P <0.05). There was a weak correlation between soil thawing speed and the thawing period (P> 0.05). There was no significant difference in soil respiration rate between soil freeze-thaw and thawing (P> 0.05), but it showed a clear trend of increase in the period of thawing (0.14-0.37μmol · m-2 · s-1), indicating that the thawing of frozen soils would significantly increase soil carbon emissions and thus increase Atmospheric CO2. The results clarify the effect of seasonal frozen soil thickness on soil respiration in the Lake Aibi, which provides a theoretical basis for revealing the carbon release mechanism in the process of global warming.