Spatiotemporal Simulation Prediction and Driving Force Analysis of Carbon Storage in the Sanjiangyuan Region Based on SSP-RCP Scenarios

Global warming and rapid urban industrialization are profoundly transforming land-use patterns and carbon storage capacity in terrestrial ecosystems. A rigorous analysis of spatiotemporal variations in regional land-use changes and carbon storage dynamics provides critical insights for sustainable land-use planning and ecological security, particularly within the context of achieving carbon peaking and carbon neutrality targets. In this study, the PLUS-InVEST model was coupled with climate change and policy constraints to construct six future scenarios. We analyzed the characteristics of land-use evolution and the spatial and temporal changes in carbon storage in the Sanjiangyuan region from 2000 to 2020. We also predicted the potential impacts of land-use shift on carbon storage. The results show the following: (1) Land-use transitions exerted significant impacts on carbon stock. The Sanjiangyuan region experienced a net carbon stock reduction of 9.9 × 106 t during 2000–2020, with the most pronounced decline (6.1 × 106 t) occurring between 2000 and 2010. (2) Under the same climate scenario, the natural development (ND) scenario exhibited decreasing carbon reserves relative to 2020 baseline levels. Notably, land-use planning scenarios demonstrated spatially heterogeneous impacts, with the ecological protection (EP) scenario consistently maintaining higher carbon stocks compared to the ND scenario. (3) Multivariate driver interactions exerted stronger control over spatial carbon storage patterns than any individual factor. These findings inform targeted land-use management strategies to enhance regional carbon sequestration capacity, promote sustainable development, and support China’s carbon peaking and neutrality objectives.