Research on Strategies for Constructing Ecological Security Patterns in Transboundary River Basins: A Case Study of the Erguna River Basin

The construction of ecological security patterns (ESPs) in transboundary river basins can support ecological connectivity and coordinated conservation. However, transboundary ESP studies remain limited in addressing basin-wide connectivity and spatial heterogeneity across national boundaries. Focusing on the Erguna River Basin across China, Russia, and Mongolia, this study aims to construct a basin-wide ESP to identify ecological connectivity patterns and key areas for ecological conservation and restoration. We identified ecological sources based on ecosystem service importance and constructed a resistance surface using distance to water, land use, fractional vegetation cover, elevation, and slope, which was further adjusted using ecological sensitivity. We then identified ecological corridors, pinch points, and barrier points. Results showed that (1) extremely important areas were ranked in the order China (34.2%) > Russia (17.0%) > Mongolia (1.9%), while extremely sensitive areas were ranked in the order Mongolia (35.3%) > China (13.9%) > Russia (1.3%); (2) the corrected ecological resistance showed a west–east pattern, with high resistance in the western and southwestern basin and low resistance in the north and east; (3) 17 ecological sources, 34 corridors, 31 pinch points, and 27 barrier points were identified, supporting a “Three Zones and Three Belts” ESP and restoration strategy. These findings support cross-border ecological connectivity priorities and coordinated conservation.