[Characteristics of Spatial and Temporal Changes in Carbon Stocks in the Middle and Upper Reaches of the Huaihe River Basin and Future Multi-scenario Simulation Prediction]

The Huaihe River Basin is located in the north-south climate transition zone of China. The change of carbon storage in this area is of great significance for predicting the future ecological protection, mitigating climate change, and maintaining sustainable development of the Huaihe River Basin. The middle and upper reaches of Huaihe River Basin （above Bengbu station） were taken as the research area. Based on the land use data from 1980 to 2020, the PLUS model was used to simulate and predict the land use types in the study area from 2030 to 2100 under the scenarios of SSP1-2.6, SSP2-4.5, SSP5-8.5, and the continuation of land use status. The carbon module in the InVEST model was used to simulate and predict the carbon storage from 1980 to 2020 and the carbon storage from 2030 to 2100 under various scenarios, and the spatial and temporal changes of carbon storage in the middle and upper reaches of the Huaihe River Basin were compared and analyzed. The results showed that： ① From 1980 to 2020, the basin showed a decrease in both cultivated land and grassland,and the area of forest,water, construction, and unused land all increased, among which the area of cultivated land continued to decrease, with a total decrease of 4 699 km² in 40 a. Construction land continued to increase, with a total increase of 4 592 km² in 40 a. ② The carbon storage in the basin showed a downward trend, with a total reduction of 1.05×10⁷ t from 1980 to 2020. ③ In the four scenarios, the area of each land type had different degrees of change, and that of the SSP1-2.6 scenario was relatively small out of the four scenarios. ④ Compared with the carbon storage in 2020, the carbon storage in the SSP1-2.6 scenario increased by 8.7×10⁴ t, the carbon storage in the SSP2-4.5 scenario decreased by 1.42×10⁷ t, the carbon storage in the SSP5-8.5 scenario decreased by 1.34×10⁷ t, and the carbon storage in the current continuation scenario decreased by 1.22×10⁷ t. The study can provide a scientific basis for land use structure management and ecological protection in the middle and upper reaches of the Huaihe River Basin （above Bengbu station） in the future.