Soil Conservation Service Spatiotemporal Variability and Its Driving Mechanism on the Guizhou Plateau, China

Abstract

The Guizhou Plateau has an extremely fragile ecological environment with prominent soil and water losses. Since 2000, conservation policies and ecological restoration projects, e.g., the Grain for Green Project (GGP), have been implemented on the Guizhou Plateau to control soil/water losses which have achieved notable accomplishments. Using the Revised Universal Soil Loss Equation (RUSLE) to estimate the soil conservation service (SCS) on the Guizhou Plateau, this study analyzed the dynamic characteristics of its spatiotemporal variation based on multiyear (2000–2018) meteorological and remote sensing data to determine its driving mechanisms. Residual analysis of the meteorological and remote sensing data was used to evaluate the effect of anthropogenic activities. Results showed a clear upward trend (1.39 t ha−1 yr−1) of SCS on the Guizhou Plateau during 2000–2018, and areas with a highly improved positive effect on SCS were distributed primarily in karst landform regions. Precipitation and vegetation fractional coverage (VFC) were found to be positively correlated with SCS on the Guizhou Plateau. Specifically, the highest proportion of significant positive correlation between precipitation and SCS was related to the Wildlife Conservation Nature Reserve (WCNR), and the highest proportion of significant positive correlation between VFC and SCS was related to the GGP, i.e., 76.59% and 53.02%, respectively. Residual analysis revealed a significant positive role of anthropogenic activity on SCS improvement via ecological engineering in areas with a poor ecological background, e.g., the GGP in western areas where the ecological environment is fragile and the problem of water/soil loss is serious. In areas with a more robust ecological background, e.g., the engineering area of the WCNR, the effect of anthropogenic activity has had a largely negative effect on SCS. The findings of this study could make an important contribution to the development of ecological management projects and the work to control soil/water losses on the Guizhou Plateau.