Ecological Network Modeling and Optimization for Photovoltaic Development on the Western Sichuan Plateau

To reveal the impact of centralized photovoltaic expansion on habitat connectivity in high-altitude cold regions, this study takes the Western Sichuan Plateau as a case study. It integrates the MaxEnt model, Markov-PLUS model, circuit theory, and graph theory metrics to construct ecological networks for 2016, 2023, and 2030 under the Inertial, Ecological Protection and Economic Development scenarios. The results indicate that photovoltaic development and its supporting infrastructure have become key factors that influence the regional ecological network. From 2016 to 2023, the area of ecological sources decreased from 6,482 km² to 2,793 km², with high-quality sources increasingly concentrated in high-altitude woodland and grassland. The number and total length of ecological corridors, while barrier points and pinchpoints became significantly clustered along river valleys and transportation corridors. Under the Ecological Protection Scenario in 2030, the extent of the high-resistance zone was effectively reduced while maintaining the scale of photovoltaic development, resulting in a higher closure and connectivity. In contrast, the Inertial Development and Economic Development Scenarios exhibited more pronounced bottleneck effects and higher risks of potential network fragmentation. The findings suggest that, measures such as site optimization, corridor reservation, and key restoration can help mitigate connectivity loss.