Ecological carrying capacity evaluation from the perspective of social-ecological coupling in the Qilian Mountains, northwest China

With population growth and rapid socio-economic development, mountainous areas are facing significant challenges in terms of their ecological environment. The ecological carrying capacity (ECC) serves as a key indicator for assessing the social, economic, and ecological sustainability of a region. Exploring the spatial and temporal changes in ECC can enhance our understanding of ecological transformations in mountainous areas. It also provides a comprehensive reference for evaluating ecological management and restoration efforts, as well as for studying overall environmental sustainability. In this study, we focused on the Qilian Mountains (QLMs), a representative alpine mountainous region, and established a composite, multi-perspective coupled ECC evaluation index system. By integrating remote sensing (RS) data and geographic information system (GIS) technology, we quantitatively analyzed the spatial heterogeneity of ECC in the QLMs using the fuzzy analytic hierarchy process (FAHP) and entropy weight method. The results showed that from 2000 to 2018, the ECC in the QLMs exhibited a spatial distribution pattern characterized by high values in the southeast and low values in the northwest. Regions with bad and medium ECC dominated, accounting for over 69% of the total area, and their gravity centers shifted towards the northwest. Approximately 85% of the regions showed an increasing trend in ECC, primarily located in the western and southern parts of the QLMs, indicating a gradual improvement in the state of the ecology and environment. However, continuous ecological control and management are still necessary in the western and northeastern regions of the QLMs. In conclusion, these findings provide valuable insights for safeguarding ecological environment security and promoting green development in the QLMs.