By the karst dynamic system theory, the Kcs is controlled by groundwater discharge  and HCO^-₃ mass concentration. The Banzhai River catchment, located in Maolan National Nature Reserve of Guizhou Province, was chosen as the study area. By the auto-monitoring technique, the discharge and water chemistry data of Banzhai River catchment were obtained. Based on the analysis of relationship between discharge, HCO^-₃ concentration and karst carbon sequestration under different precipitation conditions including storm period, no/weak precipitation period and dry season. Kcs has positive correlation with discharge and negative correlation with HCO^-₃ concentration.