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In the traditional construction of ecological security pattern, the minimum cost path is extracted as the ecological corridor based on the minimum cumulative resistance model, and the ecological nodes are identified manually. This method lacks the consideration of the exchange process of energy flow and information flow in the ecological process, resulting in a certain lack of ecological security pattern in structure and function. Therefore, an ecological security pattern construction method integrating CVOR-GWLR-Circuit model is proposed to solve the above problems by transforming natural background data into localized correction variables and adding them to the ecological security pattern evaluation model. Taking Yunnan Province as an example, firstly, the ecological security evaluation system of "Contribution, Vigor, Organization, Resilience" (CVOR) is constructed based on the importance of ecosystem services and ecosystem health, and the ecological security of Yunnan Province in 2020 is evaluated, and the ecological source areas are identified combined with nature reserves. Then, the ecological resistance surface was constructed by considering land use data and topographic factors, and the landslide sensitivity evaluation model was constructed based on geographically weighted logistic regression model (GWLR) to correct the basic resistance surface. Finally, the circuit theory model is used to extract the ecological corridor and construct the ecological security pattern in Yunnan Province. The ecological pinch points and barriers in the ecological corridor are diagnosed by the current density, so as to identify the width of the ecological corridor and identify the key areas of ecological protection and restoration. The results showed that the ecological sources area of Yunnan Province was about 69,417.78 km2, accounting for 17.6% of the total area of the study area, mainly distributed in Dehong Prefecture, southwest Yunnan, Diqing Prefecture and Nujiang Prefecture in northwest Yunnan. A total of 780 ecological corridors were generated between the ecological sources, with a total length of about 197,598.2 km, an average length of 253.3 km, and the longest path length of 932.1 km. The ecological corridors are "spider web", linking southwest, northwest, northeast, central and southeast Yunnan Province. 36 ecological pinch points and 42 ecological barriers were identified. The research results verify that the ecological security pattern constructed by integrated CVOR-GWLR-Circuit model is more reasonable, which can provide scientific basis for regional ecological protection planning and ecological corridors design. [ABSTRACT FROM AUTHOR]

Accelerated urbanization and population growth have resulted in the loss of ecological land and biodiversity, accompanied by the degradation of ecosystem services. Identifying and improving existing ecological security patterns are of great significance for maintaining the sustainable development of cities. In this study, Jinan, the capital of China's Shandong Province, was used as a case study area. Based on three ecosystem services, namely, soil conservation, water conservation and carbon fixation, ecological sources were determined. Furthermore, a resistance surface was constructed based on biodiversity. On these bases, the circuit theory concept of random walks was applied to simulate ecosystem processes in a heterogeneous landscape and identify ecological corridors, pinch points and barriers. A total of 25 ecological sources, 48 ecological corridors and 19 pinch points were identified, and restoration areas were delimited to three levels. These elements together constituted the ecological security patterns. Specifically, the ecological sources were mainly distributed in southern Jinan and were covered mostly with forest land. The ecological corridors were located mainly in the eastern and southwestern plains below the southern mountainous areas and were covered mostly with cropland. Furthermore, the eastern corridors were much longer than the southwestern corridors. Pinch points were distributed mostly along rivers or around large-scale construction land. Barriers were distributed mainly in Zhangqiu District and northern Licheng District. Based on these findings, hierarchical restoration areas were delimited. Differentiated development contradictions in restoration areas were discussed, and corresponding ecological protection measures were proposed. An ecological security optimization pattern of "one center, two wings, and two belts" was finally proposed to provide planning strategies for decision-makers. [ABSTRACT FROM AUTHOR]