Background The Nyang River Basin serves as a crucial ecological security barrier in southeastern Xizang. Due to its unique geographical location and fragile alpine environment, it faces significant pressures from intensifying human activities and climate change. These factors have led to increasing landscape fragmentation, declining biodiversity, and reduced ecological resilience, presenting urgent challenges for regional sustainable development. Scientifically constructing the ecological security pattern of the Nyang River Basin is essential for enhancing ecological resilience, maintaining ecosystem stability, and promoting sustainable regional growth.

Methods Focusing on the Nyang River Basin, we analyzed four key ecosystem service indicators and equally weighted and summed their evaluation results to derive integrated ecosystem service importance. Zones classified as “extreme importance” were selected as ecological sources. We then constructed a comprehensive resistance surface by combining the Minimum Cumulative Resistance (MCR) model with the Entropy Weight Method (EWM). Using the circuit theory approach in the Linkage Mapper tool, we extracted ecological corridors and pinch points, thereby established the ecological security pattern. Finally, drawing on an extensive review of relevant literature and the ecological governance evaluation methods it contains, and in light of the Nyang River Basin’s specific characteristics, we systematically assessed its ecological security pattern and proposed targeted restoration strategies and optimization pathways.

Results 1) Ecological security within the Nyang River Basin exhibits pronounced spatial differentiation, increasing from west to east. High and relatively high-security areas cover 9 425.90 km² (40.3% of the basin), while low and relatively low-security areas cover 9 176.12 km² (39.23%). 2) We identified 44 ecological source patches totaling 1 455.42 km² (6.4% of the basin), primarily clustered in the middle and lower reaches, with scattered patches in the upper reaches. From these sources, 107 ecological corridors were mapped—forming a dendritic network 1 135.68 km in length−with higher density in the east and lower density in the west; among them, 63 were classified as “critical” and 33 as “important.” Ecological pinch points cover 103.42 km² and align with areas of dense forest and grassland cover, varied terrain, and levels of human disturbance, also exhibiting an east-dense, west-sparse distribution. 3) Based on the construction and evaluation of the ecological security pattern, a “Three Zones and Three Belts” ecological construction strategy is proposed. The core zones comprise an Ecological Restoration Zone, focused on rehabilitating degraded source areas; an Ecological Corridor Protection Zone, dedicated to preserving identified corridors and pinch points; and an Ecological Conservation Zone, aimed at safeguarding high-integrity landscapes. The supporting belts include a Biodiversity Protection Belt, an Ecological Corridor Restoration Belt, and an Ecological Security Construction Belt. Together, these elements form a “zone-led, belt-coordinated” basin-wide ecological protection network.

Conclusions The results can effectively enhance regional ecosystem service functions, safeguard biodiversity, and provide a solid foundation for coordinating ecological security with economic development and formulating differentiated protection and restoration strategies.