δ¹³C value in soil organic matter is closely related to types and biomass of the plants growing thereupon during C₃ and C₄,and plant biomass,however,depended on the environment.Therefore,the δ¹³C value in soil organic matter can be used to reconstruct paleoecology and paleoclimate,and has been applied in studies on reconstruction of paleo-environment as well as global change.Owing to impacts of atmospheric humidity,partial pressure of CO₂,temperature and microbial decomposition and so on,in some cases exact correspondence between characteristics of δ¹³C in soil organic matter,ratio of C₃ and C₄ plants and regional environment (mainly climate) does not exist.So mechanism and its affecting factors of the application of the carbon isotopic interpretation should be probed further.Stresses should also be laid on researches on relationship between the modern vegetation and the δ¹³C value in soil organic matters,impact of anthropological activities on stable isotope of soil organic matters,and C cycling process within the soil-plant-atmosphere system in the years to come.If so,the study of stable isotope in soil organic matter could find extensive application in a variety of fields.