Desertification, as one of the most severe socio-economic, environmental and ecological problems, has attracted widespread attention. In this study, the severity of desertification in the southeastern edge of the Mu Us sandy land of China was classified into five stages using the space-for-time method. A field experiment was conducted in July 2015 to investigate the dynamics of soil organic carbon (SOC) and total nitrogen (TN) concentrations and stocks. The results show that SOC and TN concentrations and stocks decreased significantly with the severity of desertification, reducing SOC and TN concentrations by 55.5% and 55.1% in 0-30 cm depth, SOC and TN stocks decreasing by 54.4% and 54.0%, respectively. The losses of SOC and TN stocks indicate that the impacts of desertification were more evident in upper soil, because the losses in them were higher than those in other layers, and early stages are vital to the restoration of desertification for more losses of SOC and TN stocks. SOC (4.25 x 10(8) kg) and TN (0.71 x 10(8) kg) accumulated from 2003 to 2015 indicate that desertification was reversed. Overall, key stages of combating desertification were identified, and the feasibility of integrating field experiment data and temporal-spatial data to evaluate the dynamics of desertification was verified.