Based on the background of carbon peaking and carbon neutrality goal strategies, it is important to explore the impact of land use change on carbon storage and the drivers of spatial variation in carbon storage in the Northwest Arid Zone, which is vital to improve the carbon sink increment of the regional ecosystem and promote the regional carbon breakeven. The arid region of northwest China is an extremely fragile natural ecology, and with the rapid advancement of new urbanization, the rate of land use change has accelerated significantly, which has a certain impact on the carbon storage and fixation capacity of ecosystems. The PLUS-InVEST model was used to simulate the spatial and temporal evolution characteristics of carbon storage under natural development, intensive development, water resource constraint, and ecological protection scenarios in Jiuquan City in 2035, and the parameter optimal geographic detector model was used to analyze the spatial divergence drivers of carbon storage. The results showed that:① the area of cultivated land, watershed, and construction land in Jiuquan City showed a significant increasing trend from 1990 to 2020, whereas the area of the remaining land use types showed a decreasing trend. ② The carbon storage in Jiuquan City increased from 7 722 808.1 t to 7 784 371 t from 1990 to 2020, and the conversion of grassland into unused land was the main cause of the loss of regional carbon storage, accounting for 85% of the total loss. ③ All four development scenarios in 2035 showed an increasing trend of carbon storage, among which the ecological protection scenario had the most significant increase, with an increment of 76 989.29 t. ④ The degree of land use, population density, GDP density, and NDVI were the main driving factors of the spatial variation in carbon storage in Jiuquan City, among which the degree of land use had the strongest explanatory power (q value of 0.849), and the interaction of natural and anthropogenic factors enhanced the explanatory power of each factor on the spatial variation in carbon storage. The results of the study can provide a scientific basis and decision basis for the integrated ecosystem management and territorial space optimization in Jiuquan City.
Keywords: InVEST model; Jiuquan City; PLUS model; carbon storage; parameter optimal geographic detector.