Incorporating complex network theory to deconstruct ecological security network structure: Multi-layer nested karst ecological systems management

With the accelerating impacts of climate change and urbanization, constructing ecological security networks (ESN) has become crucial for maintaining ecosystem stability. However, traditional models lack micro-structural analysis of ESN, resulting in insufficient optimization of ecological management. This study selects three representative sites with distinct geomorphological features and ecological degradation gradients in a typical ecologically vulnerable karst plateau region. By comprehensively considering the dynamic interplay between natural capital and collective consumption in ecological conservation, developed an ESN based on ecosystem service (ES) supply-demand relationships. Utilizing complex network theory, deconstructed the topological characteristics of ESN architecture and proposed a multi-layered nested ecological management framework. Findings reveal that the quantity and distribution of ecological source areas are significantly influenced by human activities and restoration measures, with source area clustering determining corridor lengths. The proportions of pinch points and barrier points correlate with regional characteristics. Most ecological nodes concentrate within specific ranges, creating strong internal connectivity within ecological communities but insufficient inter-community connections, highlighting the necessity for targeted ecological governance. Critical nodes demonstrate superior efficiency in information diffusion and species migration while controlling cross-community resource flows, their failure could trigger catastrophic network collapse. To address current network deficiencies, constructed multiple potential ecological corridors to mitigate centrality congestion and prevent over-reliance on single nodes. A comparative analysis of network robustness before and after optimization demonstrates that increased redundant pathways enhance resistance to external disturbances. This research develops a hierarchical management framework integrating "micro-nodes, meso-communities, and macro-zoning", providing replicable spatial planning strategies for karst plateaus and other fragile ecosystems.