中文摘要：

大气CO2浓度的升高通过植物-土壤-微生物的相互作用对陆地生态系统中最大碳库土壤的稳定性产生重要影响。大气CO2浓度升高,影响许多植物生长发育过程,进而影响土壤有机碳输入量。与此同时,土壤微生物的群落与功能也会随之发生变化,参与土壤碳的转化,深刻影响陆地生态系统的碳循环。文章分析了大气CO2浓度升高影响农田土壤碳循的有关过程,包括高CO2浓度条件下,作物地下部分的生长响应,以及向土壤中输入作物光合有机物量和质的变化,探讨了土壤碳库对大气CO2浓度升高反馈的土壤微生物作用机制,进一步解析了土壤微生物群落结构在土壤碳与大气CO2浓度之间的相互作用,提出研究土壤有机碳转化的土壤微生物作用机制是预测全球气候变化条件下的农田土壤碳循环规律的关键。图1,参79。

英文摘要：

Soil is the largest carbon （C） pool in terrestrial ecosystems.Elevated atmospheric CO2（eCO2） influences the stability of this C pool via the plant-soil-microbe interaction.Many plant species exhibit significant increase of growth in response to eCO 2 ,which is likely to alter organic carbon input to the soil.The community structure and function of soil microorganisms may also change under eCO 2 and probably have substantial influence on carbon cycling in terrestrial ecosystems as these microorganisms are subjected to be involved in the transformation of soil carbon.This paper summarized the effect of eCO 2 on soil carbon cycle,which included the root growth of crops in response to eCO 2 ,and quantitative and qualitative alternations on the photosynthates input to the soil under eCO 2.The feedback mechanisms of soil carbon pool in response to eCO 2 were also addressed in the perspective of soil microorganisms.It is proposed that the soil microbial community should be further investigated in order to better understand the relationship between soil carbon and atmos -pheric CO2.Thus,the mechanism of soil microorganisms being involved in the turnover of soil organ carbon is essential to clarify the pattern of carbon cycling in arable soils under global climate change.