【摘要】 对重庆金佛山林地、裸地表层岩溶生态系统CO2体积分数进行了野外监测,揭示了CO2体积分数变化规律,这种变化与土壤温度有密切的关系。林地与裸地各个层次土壤的CO2体积分数与土温呈一致性变化,随着土温的升高或降低而相应的增加或减少。文章进一步揭示了林地植被平抑这种动态效应,而裸地则响应于温度变化;这种不同植被系统下的动态差异在解释岩溶沉积记录和讨论岩溶作用与碳循环的关系时值得充分注意。更多还原

【Abstract】 Recent studies on karst process and terrestrial carbon cycling have concentrated on dynamics of carbon fluxes among soil, air, and water in association with the carbon isotopic equilibrium. This investigation aims at depicting change of CO2 concentration in epikarst under different vegetations in summer. Compared with the significant variation of temperature of free air and of surface soil, soil temperature at different depths varies in the range. More gentle variation of soil temperature of soil temperature is found under forest than under uncovered land. The variation of CO2 concentration is largely controlled by the soil temperature regimes. More significant variation is likely to occur of soil carbon fluxes under grass due to the sensitivity to temperature changes by the limited vegetation cover. This illustrates sensitivity of epikarst ecosystem.更多还原