The Application of Radiocarbon in the Study of Soil Carbon Cycles
放射性碳同位素在土壤碳循环中的应用

The carbon cycles in the soil is important for the study of the global change because the carbon deposited in the soil is two times more than that in the atmosphere and three times more than that in the plant and animal. While the final mechanism of the terrestrial carbon cycles is still not clear without the understanding of the soil dynamics, the radiocarbon provides a simple and convenient method to study the turnover of the soil organic matter (SOM).Several models and methods in the study of soil organic matter turnover by the application of radiocarbon were introduced in this paper. It was pointed out that the SOM radiocarbon application may be used to study the carbon cycle of longer time scale such as decades and more, whereas its application to the soil CO2 can be used to study the carbon cycle of shorter time scale such as seasons or one year. Other applications such as those in the study of fine root age and land use change were also introduced in this paper. Although radiocarbon had been used in the study of carbon cycle, its application was very limited so far and some problems had been found. At last, some issues unsettled were put forward and the future development direction and fields using this method to study the SOM dynamics were introduced.