Spatio-temporal variations and drivers of ecological carrying capacity in a typical mountain-oasis-desert area, Xinjiang, China

The aggravation of climate change and human activities have challenged the fragile ecology of the arid and semi-arid Xinjiang in Northwest China. The concept of ecological carrying capacity (ECC) refers to the ability of an ecosystem to support the healthy development of the human social system and provide adequate resources and enabling environmental conditions. A comprehensive evaluation of ECC could rationalize ecological restoration and sustainable development. This study evaluates the ECC of Xinjiang's unique landscape structure of mountain-oasis-desert ecosystems from 1982 to 2017, using remote sensing data such as vegetation and evapotranspiration and geographic information system technology, and index evaluation method. The ECC patterns and change trends were explained from multidisciplinary perspectives, and the internal drivers of ECC spatio-temporal variations were evaluated by partial correlation analysis and residual analysis. The results showed an average ECC value at the median level of 0.29. For spatial distribution, ECC value decreased from west to east, the median ECC area was the most widespread, and the poorest ECC area was concentrated mainly in Southern Xinjiang's deserts. From the analysis of the significance of the change, ECC in Xinjiang had generally declined, with the decreasing areas exceeding the increasing areas. The driver analysis found temperature exerting a greater impact than precipitation on ECC improvement, and human activities positively impacted ECC. Altitude was closely associated with ECC distribution with better ECC in high elevation areas. The positive correlation between urbanization and ECC level was significant. The findings provide a relatively comprehensive and synoptic framework for ecological assessment in arid and semi-arid areas to inform sustainable development and ecological restoration in Xinjiang.