A Refined Framework for Alpine Ecological Security Patterns: Identifying Key Restoration Areas under Different Scenarios

To construct and optimize multiscenario ecological security patterns, this study focuses on the Qilian Mountains, located in the alpine region of western China. Using land-use data from 2000 and 2020, as well as 3 projected 2060 scenarios of natural development, ecological protection, and ecological restoration, an integrated ecological security evaluation model was developed. This model incorporates ecosystem services, ecosystem health, and ecological risks, with indicator weights determined through a random forest algorithm. Ecological sources were identified by combining morphological spatial pattern analysis with biodiversity assessments, and circuit theory was used to extract ecological corridors. The results show substantial grassland expansion and a reduction in unused land between 2000 and 2020. Under the ecological protection scenario, habitat quality was the highest, with ecological source areas reaching 50,358 km 2 , and corridor connectivity and patch integrity outperforming those in the natural development scenario. The ecological restoration scenario also promoted grassland expansion and improved ecological connectivity. Guided by the “one belt, one screen, three zones, and multiple corridors” framework, this study proposes spatial optimization strategies to support regional ecological conservation and sustainable development.