[Land Change Simulation and Grassland Carbon Storage in the Loess Plateau Based on SSP-RCP Scenarios]

Exploring the spatial distribution of land use/coverage (LUCC) and ecosystem carbon reserves in the future of climate change can provide a scientific basis for optimizing the distribution of land resources and formulating social economic sustainable development policies. In this study, we integrated the plaques generating land use simulation (PLUS) model and ecosystem services and weighing comprehensive evaluation (InVEST) model. Based on the CMIP6-based sharing socio-economic path and representative concentration path (SSP-RCP), we evaluated the Loess Plateau for time and space dynamic changes in LUCC and ecosystem carbon reserves, analyzed the impact of driving factors on different regions, and explored the correlation between carbon reserves in various regions. The results showed:① In the future, the three scenarios were similar to the LUCC changes. The area of cultivated land, grassland, and unused land would be reduced to varying degrees, and the construction land had expanded sharply. The increase in the three scenarios was 29.23%-53.56% (SSP126), 34.59%-63.28% (SSP245), and 42.80%-73.27% (SSP585). ② Compared with that in 2020, the carbon reserves of SSP126 sites in 2040 increased by 1.813 8×10⁶ t, and in the remaining scenarios it would continue to decline. By 2060, the grassland carbon reserves in the three scenarios decreased by 13.391×10⁶, 33.548×10⁶, and 85.871×10⁶ t, respectively. ③ From the perspective of space correlation, the carbon reserves of the Loess Plateau were correlated between cities. The difference in future scenarios was not significant. The hotspots were distributed in the middle and north of the research area. There was no obvious cold spot area. ④ The changes in land use were predicted to increase or lose carbon reserves. Forestry, cultivated land, and grassland had more carbon reserves those in than other land types. Increasing their area and restrictions on the conversion of other land types should increase the ecosystem carbon reserves.