采用现代微观测试技术手段，对我国温带、亚热带地区典型土壤剖面深土层中有机质与粘土矿物之间的结合机制及其稳定性，开展深入系统的实验研究，查明不同气候环境、不同成土作用条件下深土层中有机质的化学组成特征、粘土矿物学性质、以及环境介质条件等对有机质-粘土矿物之间结合状态及稳定性的影响；结合对土壤剖面不同层位中有机质组成、结构以及有机质-粘土矿物结合方式演化研究，弄清土壤剖面中有机质及其与粘土矿物结合形式与有机质稳定性随深度（时间）演化的原因，揭示深土层中有机碳对土壤圈碳循环过程的影响。

To obtain better understanding of effect of chemical compositions of organic matters, clay mineralogy, and environmental media on interaction mode between organic matter and clay mineral，and stabilty of organic matters in deep soils under different climate and pedogenesis conditions, experimental study on interactions between organic matter and clay mineral and stabilty of organic matters in typical deep soil profiles in temperate and subtropical climate zones in China is undertaken using modern microscopic analysis methods and techniques. In addition, study is also undertaken to make clear the evolution of interaction mode between organic matter and clay mineral and stabilty of organic matters with deep (or time) of the soil profile, by combining the results of evolution of chemical composition and structure of organic matters and interaction mode betwwen organic matter and clay mineral in different horizons of the deep soil profiles, and therefore, shed light on the effect of organic matters in deep soils on the pedosphere cycling process of soil carbon.