Assessment and Prediction of Ecosystem Services and Identification of Key Areas for Ecological Restoration: A Case Study of the Loess Plateau in China

Ecosystem services play a crucial role in maintaining ecological balance and supporting socio-economic development. However, long-term human activities and climate change have led to severe ecosystem degradation and exacerbated soil erosion on the Loess Plateau. This study takes the Loess Plateau as a case study and using key models such as Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) to analyze the spatiotemporal variations of five ecosystem services—water yield, habitat quality, windbreak and sand fixation, soil conservation, and net primary productivity (NPP)—from 2000 to 2020. Based on the land use types projected by the Patch-generating Land Use Simulation (PLUS) model for 2025 and 2030 under natural development, ecological protection, and cropland protection scenarios, the study simulates these five ecosystem services and the comprehensive ecosystem service index for the Loess Plateau in 2025 and 2030. Finally, an ecological risk assessment model based on the inverse transformation of ecosystem services is constructed to identify key ecological restoration areas on the Loess Plateau by 2030. The results indicate: (1) From 2000 to 2020, water yield, soil conservation services, and NPP on the Loess Plateau showed a significant increasing trend, The unit area sand fixation capacity displayed a spatial pattern of higher values in the Northwest and lower values in the Southeast, while soil conservation and NPP exhibited the opposite trend, with higher values in the Southeast and lower values in the Northwest. Water yield decreased from the Southeast to the Northwest. During this period, the comprehensive ecosystem service index of the Loess Plateau generally declines, but the balance and synchronicity of ecosystem services improve, with a reduction in regional disparities. (2) Different future scenarios have different effects on the regional pattern of ecosystem services and restoration. Among future scenarios, the ecological protection scenario is most conducive to enhancing comprehensive ecosystem services, reducing the proportion of medium- and high-priority restoration zones. The cropland protection scenario has the lowest proportion of general restoration zones, but local ecological risks increase. The findings of this study can provide a scientific basis for ecological restoration and land-use planning on the Loess Plateau, promoting the long-term stability and sustainable development of ecosystem services.