[Temporal and Spatial Evolution and Prediction of Carbon Storage in the Haixi Prefecture of Qinghai Province Based on PLUS-InVEST Model].

Abstract

The change of land use type seriously affects the spatial distribution pattern of regional carbon stocks. Exploring the land use status under future scenarios can provide an important reference for the spatial optimization of land use structure, carbon budget balance, and sustainable development in inland arid areas. Based on the land use types of the Haixi Prefecture in 2000, 2010, and 2020, the characteristics of land use change in the study area over 20 years were analyzed. The PLUS-InVEST model combined with 13 driving factors was used to simulate and predict the temporal and spatial distribution characteristics of land use and carbon storage under natural development, ecological protection, and urban development scenarios in 2030. The results showed that： ① From 2000 to 2020, the main land types in the Haixi Prefecture were grassland and unused land； the area of grassland continued to decrease, mainly transferred to unused and construction land, whereas the area of other land types showed an increasing trend. ② Compared with that in 2020, under the natural development scenario in 2030, the area of forest land will decrease by 204.86 km², indicating a decrease of 24.18%, and the area of grassland will decrease by 4 167.02 km². Under the ecological protection scenario, the area of forest land and grassland will increase by 55.47 km² and 929.41 km², respectively. Under the urban development scenario, the construction land area will be 672.84 km², indicating an increase of 17.34%. ③ From 2000 to 2020, the total carbon storage decreased by 162.04×10⁶ t, showing a continuous downward trend. High carbon storage values were distributed in the eastern and southern parts of the study area, while low carbon storage values were mainly distributed in the Qaidam Basin and its periphery. ④ In 2030, carbon storage under the ecological protection scenario will increase by 84.78×10⁶ t and 86.16×10⁶ t compared with that under the natural and urban development scenarios, respectively, indicating that ecological protection can effectively increase carbon storage in the study area. These findings provide data support for rational land use planning and coordinated regional development in the Haixi Prefecture.