Characterization of spatial and temporal correlation between ecosystem service and human activity intensity in Xinjiang, China based on supply and demand.

The balance between supply and demand of ecosystem services in arid zones is crucial for regional sustainable development. Taking Xinjiang as the study area, we analyzed the spatial and temporal variations of the supply and demand of food production, habitat quality, carbon storage, soil conservation, water yield and greenfield leisure in relation to the intensity of human activities during 2000-2020 by using bivariate spatial autocorrelation method. The results showed that from 2000 to 2020, the six ecosystem services in the study area were in a state where their supply was far greater than demand (supply/demand ratio>1). The supply of water yield, carbon sto-rage and soil conservation per unit area increased by 28.61 m³·km^-2, 18.24 t·km^-2 and 3147 t·km^-2, respectively. The demand increased by 14.2 m³·km^-2, 59.85 t·km^-2, and 7151.52 t·km^-2, with insignificant changes in supply and demand for food production, greenfield leisure, and habitat quality. The supply-demand ratios for food production and water yield increased by 118.2% and 34.9%, respectively. Carbon storage and soil conservation decreased by 83.7%, 108.9%, and 20.9%, respectively. The supply and demand ratios of habitat quality and greenfield leisure did not change significantly. From 2000 to 2020, human activity intensity index (HAI) in 98% of the study area were below 0.25. Spatially, HAI showed a pattern of sporadic distribution, with the Tianshan Mountain as the boundary, high in the north, low in the south, and sporadic distribution. The supply/demand ratios of food production, water yield, and habitat quality showed a significant negative correlation with HAI as a whole. The supply/demand ratios of carbon storage, soil conservation, and greenfield leisure showed a significant positive correlation with HAI. The supply-demand ratios of food production, carbon storage, habitat quality, and greenfield leisure were mainly low-high clustered with HAI in the urban belt of the northern slope of Tianshan Mountain and the oasis area of Tarim River Basin, while the supply-demand ratios of soil conservation and water yield were mainly high-high clustered with HAI in the Tianshan Mountain Range and the Tarim River Basin.