Abstract: Qilian Mountains are an important ecological security barrier in the western part of China. It is of great significance to construct an ecological security pattern of the Qilian Mountains to maintain ecological functions and biodiversity. Based on the research paradigm of “ecological source area-resistance surface-corridor”, we initially constructed an ecological network using the morphological spatial analysis (MSPA) method, InVEST models, and circuit theory. By combining social network analysis and robustness assessment, we analyzed the characteristics and resilience of ecological networks, thereby constructing the ecological security pattern. Based on the dual attributes of structure and function, combined with the MSPA and InVEST models, we identified 78 ecological source areas, mainly located in the forest land in the northern part of the Qilian Mountains, the grassland and water bodies in the southeastern part, and the Yanchiwan in the northwest. There were 175 ecological corridors, 280 ecological junctions (with a total area of 47.5 km²), 188 ecological barriers (with a total area reaching 1009.0 km²). Using Gephi, the centrality of ecological source nodes was classified, with the highest level of degree centrality comprising four nodes and the highest level of betweenness centrality comprising 32 nodes, which indicated that the four ecological sources in the Qilian Mountains served as hubs in the ecological network, while the other ecological sources primarily functioned as “bridges” connecting different parts. The robustness of ecological network connectivity and vulnerability robustness showed a downward trend under intentional and random attack scenarios, but the vulnerability robustness decreased faster, indicating that the functional aspects of the Qilian Mountains ecological network were more fragile than its structural aspects and more reliant on nodes with high centrality. Based on the global efficiency index and connectivity index, the ecological corridors were modified to propose an ecological security pattern of “one screen, four zones, and multiple corridors”.

Key words: Qilian Mountains, circuit theory, social network analysis, robustness evaluation, ecological security pattern