[Land use Change and Its Impact on Carbon Stock in the Tarim River Basin from 1990 to 2020].

Abstract

Land use is one of the important factors causing the change in ecosystem carbon storage. Studying the spatio-temporal evolution characteristics of carbon storage driven by land use change is of great significance for enhancing the carbon sequestration capacity of terrestrial ecosystems, slowing down the effect of climate warming, and helping to achieve the goal of "dual carbon." Taking the Tarim River Basin as the research object, based on four periods of land use data from 1990 to 2020, the InVEST model carbon module was applied to estimate and analyze the temporal and spatial evolution characteristics of carbon storage in the basin, and the impact of land use change on the carbon sequestration capacity of the basin ecosystem and the spatial differentiation driving law of carbon storage were discussed. The results showed as follows： ① Grassland and unused land were the main land use types in the Tarim River Basin, accounting for more than 90% of the total land types, followed by cultivated land, forest land, water area, and construction land. From 1990 to 2020, the area of cultivated land, construction land, and unused land increased, while the area of grassland, forest land, and water area decreased. The total transfer area of land use type in the basin from 1990 to 2020 was 2.19×10⁵ km², and grassland was the main transfer type （accounting for 44.22% of the total transfer area）, which was mainly converted into unused land and cultivated land. ② The overall spatial distribution of carbon stocks in the Tarim River Basin was lower in the middle and higher in the surrounding areas. The high-to-high-cluster and high-to-low-cluster carbon stocks were mainly located in the distribution areas of woodland and grassland, and the low-value carbon stocks were mainly distributed in the unused land type areas in the middle of the Tarim River Basin. Over the past 30 years, an accumulative loss of 9×10⁷ Mg was observed. The center of gravity of carbon storage change shifted to the southeast, and most of the areas of carbon storage reduction were cultivated land and unused land expanding to the surrounding areas, encroaching on grassland and forest land with higher carbon density. ③ The contribution of different land use types to carbon storage was grassland, forest land, cultivated land, unused land, construction land, and water area. ④ The spatial differentiation of carbon stocks in the Tarim River Basin was influenced by various driving factors such as terrain, climate, environment, and population and their synergies.