中文摘要：

生态系统地下碳输入与输出过程是陆地生态系统碳分配和转化的核心,并直接影响着全球碳循环。陆地生态系统凋落物、根系周转、根系分泌物、土壤有机碳、土壤微生物和土壤呼吸是地下碳输入与输出过程中的重要组成部分。由于这些组分非常复杂且其研究技术和方法受到限制,目前人们对陆地生态系统地下碳输入与输出过程尚缺乏全面的认识,故在陆地生态系统碳循环研究中存在诸多的不确定性。该文概述了凋落物、根系周转、根系分泌物、土壤有机碳、土壤微生物和土壤呼吸的研究方法,以及它们对气候变化的响应,探讨了陆地生态系统地下碳输入与输出过程中的研究难点,并对未来需要深入探究的一些领域进行了展望。

英文摘要：

The input and output processes of below-ground carbon of ecosystems are the core components of carbon allocation and transformation in terrestrial ecosystems and directly affect global carbon cycling. Litterfall, root turnover, root exudate, soil organic carbon, soil microbe and soil respiration are important parts of the input and output processes in terrestrial ecosystems. Because the parts are implicated and we have limited techniques and methods to measure the parts, the input and output processes of below-ground carbon of terrestrial ecosystems are still poorly understood. Therefore, results of carbon cycling in terrestrial ecosystems are uncertain. We summarize the different methods used for studying litterfall, root turnover, root exudate, soil organic carbon, soil microbe and soil respiration and the responses of plant parts to climatic changes. We discuss the difficulties in researching the input and output processes of below-ground carbon of terrestrial ecosystems and propose several topics for further research.