Construction of ecological corridors in complex terrain areas based on the ’cost-function-ecological benefit’ model

The Western Sichuan Plateau stands as a vital ecological barrier in China. In recent years, rapid urbanization and infrastructure development have led to increased ecosystem fragmentation in the region, compression of species habitats, and significant challenges to ecosystem service functions and biodiversity conservation. Constructing ecological corridors can help maintain landscape connectivity and preserve biodiversity by providing habitats for various species. Additionally, they can enhance population viability and species richness at both local and regional scales. Current research focuses on the construction of ecological networks and the potential impacts of corridors. Few studies consider corridor width as an object of study. This study addresses the width of corridor construction, aiming to support the practical implementation of corridor projects and explore the coordination between corridor costs and functionality at different widths. Based on an evaluation of ecosystem service functions and in conjunction with natural reserves, this study identified significant ecological source. Four primary resistance factors—land use type, elevation, slope, and Degree of relief—were selected to construct resistance surfaces. The MAXENT model is introduced to identify potential landslide-prone areas, and the resistance surfaces are accordingly adjusted. Potential corridors are identified utilising circuit theory. Subsequently, by employing the IEW-TOPSIS model, different ecological corridor widths are evaluated in terms of “cost-function-ecological benefits” to determine suitable corridor widths for the Western Sichuan Plateau. Results reveal significant variations in ecological corridor widths across different regions of the plateau. Taking topographical factors into account, 1400 m emerges as the most optimal width twice, while 800 m, 1700 m, and 2000 m each appear once. The corridor width evaluation system can provide decision support for ecological corridor construction in the Western Sichuan Plateau, contributing to the preservation of ecological security in the Qinghai-Tibet Plateau in China.