Risk Assessment and Management of Potential Invasive Alien Species: A Study on Cenchrus purpureus in the Gaoligong Mountains

This study investigated Cenchrus purpureus in the southern part of the Gaoligong Mountains and quantified its invasion risk using an integrated approach. We combined the Drivers–Pressures–State–Impacts–Responses (DPSIR) model, Analytic Hierarchy Process (AHP), Structural Equation Modeling (SEM), and Traditional Ecological Knowledge (TEK). We adopted non-random sampling techniques to conduct a survey on the cognition, hazards, utilization and management of C. purpureus among 402 respondents from 25 villages. Our results classify C. purpureus as a medium-risk species (Level II). We identified a central socio-ecological dilemma: while 36.1% of communities use it for fodder, 54% report that it causes soil degradation, signaling potential long-term agricultural losses. SEM analysis confirmed that the willingness to manage the invasion is directly influenced by these usage patterns and risk perceptions. The traditional ecological knowledge of Cenchrus purpureus was highly consistent with scientific assessment, validating its use as an early warning indicator. Therefore, our study validates a multidisciplinary framework that integrates models (DPSIR, AHP, SEM) with traditional knowledge for a holistic assessment of C. purpureus invasion. This approach offers a replicable strategy for ecosystem management in global biodiversity hotspots in the mountainous regions.