SCNC model,a soil organic carbon simulation model developed in Changsha, was being compared with the model developed at Rothamsted (ROTHC 26.3) in this study. Both models were used to simulate the dynamic changes of organic carbon in paddy soils in the Middle Basin of the Yangtze River. It was showed that SCNC model was suitable for simulating the changes of organic carbon in paddy soils and ROTHC 26.3 model was not fit in the Middle Basin of the Yangtze River. The error of equilibrium simulating and mea...