Identifying priority areas for ecological conservation and restoration based on circuit theory and dynamic weighted complex network: A case study of the Sichuan Basin

Regional ecological security is a pressing issue in the context of escalating human-environment conflicts. Ecological networks(ENs), the fundamental tool for characterizing ecosystems, have enabled further quantitative analysis at the micro level by integrating with complex networks in recent years. However, most studies neglect the unreliability of unweighted complex networks and the dynamic characteristics of ENs. This paper takes the Sichuan Basin as the research area and adopts the following methods. Firstly, it integrates landscape ecology and ecosystem services to construct the ENs using Linkage Mapper. Secondly, it introduces the cost-weighted distance as the weight to build complex networks and identifies potential pivot ecological sources and key ecological corridors based on the topological features of the weighted complex networks in 2000, 2010, and 2020. Thirdly, it applies circuit theory to detect ecological pinchpoints and ecological barrier points within the corridors as priority areas for ecological conservation and restoration. The results show that the ENs in the study area are denser on the northern and southern sides, and some ecological corridors change direction due to variations of resistance surfaces and landscape morphology. Through dynamic analysis of the weighted complex networks, 27 potential pivot ecological sources and 25 key ecological corridors are identified; then, 28 priority conservation areas and 10 priority restoration areas within these ecological corridors are extracted based on circuit theory. The study reveals a certain correlation between the distribution of ecological nodes and water bodies. Furthermore, comparing the weighted and unweighted complex network, we find that the weighted complex network is more reasonable, with 64.2% of ecological sources showing lower betweenness centrality than that in the unweighted network, reflecting the obstacles that urbanization poses to ecological networks. This study explores the impact of constantly changing resistance surfaces on the overall ENs and their components through dynamic analysis. The evolving topological features reflect the feedback of the ENs to external environmental changes, as well as the dynamic characteristics of the real ENs. Therefore, the findings of this study provide valuable references for ecological conservation and governance efforts in Sichuan Basin, promoting regional ecological security and the advancement of ecological civilization.