温带森林对气候变化的响应非常敏感，森林土壤碳截获是全球碳收支不确定性的重要来源之一。我国温带森林幅员辽阔，且多以中幼林为主，探讨群落发育过程的土壤碳截获规律与气候变化背景下的土壤增碳趋势，对于科学评估我国森林生态系统固碳潜力意义重大。项目以温带森林为研究对象，采用年代序列样地法确定红松阔叶混交、云冷杉和落叶松群落发育序列，辅以年轮气候学和多种同位素联合测定，以凋落物分解、细根周转和土壤微生物结构变化为影响土壤碳截获的关键生物参数，揭示群落年龄结构变化和气候变化驱动的土壤碳截获规律、机制和动力学模型，构建基于温带森林土壤图件、群落分布图件和气候图件嵌套的区域尺度综合模型，诠释地带性顶极群落在量化天然森林固碳潜力评估中的普适作用，为科学体现我国中幼龄居多的天然森林生态系统固碳潜力提供科学支持。

Forest soil carbon sequestration represents one of the major uncertainties in predicting the global carbon budget. Temperate forests are very sensitive to climate change. For the wide distribution and young-stand dominance of temperate forest in China, it’s critical to explore the law, the trend, and the research methodology of soil carbon sequestration during forest community development, which is of great significance in the scientific assessment of forest ecosystem carbon sequestration potential under the changing climate. Taking dominant temperate forest types in China, broadleaved Korean pine mixed forest, Spruce-fir forest and Larch forest, as objects and three key biological parameters as litter decomposition, fine-roots turnover and community structure of soil microbe, this project, using method of chronosequences, dendroclimatology and joint determination of multiple isotopes, intend to study the kinetics and mechanism in soil carbon sequestration driven by changes in forest age and climate; to build the nested regional scale model on the basis of soil maps, community distribution maps and the climate maps, to interpret the pervasive role of the zonal climax forest in assessment of carbon sequestration potential of the natural forests. The output will provide scientific support to highlight the importance of carbon sequestration potential of the natural forest ecosystem which dominated by young stands in China.