Ageratina adenophora, globally recognized as one of the most aggressive invasive alien plants, had exhibited rapid and extensive expansion within China's Yangtze River Basin, posing severe and escalating threats to regional ecological security, biodiversity conservation, and socio-economic development. This study presents a comprehensive investigation into the invasion ecology characteristics, spatiotemporal risk patterns, and underlying dispersal mechanisms of Ageratina adenophora within the ecologically critical Yibin region, located in the upper reaches of the Yangtze River. By employing systematic quadrat surveys and Principal Component Analysis (PCA), we meticulously quantified habitat preferences and invasion features across diverse landscapes. Concurrently, the MaxEnt species distribution model, which was rigorously calibrated and validated, was utilized to assess current invasion risks and identify the dominant environmental drivers facilitating its spread. The results revealed that: 1) Ageratina adenophora had established widespread populations across Yibin, successfully colonizing diverse heterogeneous landscapes, including resource-rich habitats (e.g., abandoned land and secondary forests at forest edges) and multi-stressor environments (e.g., building crevices and areas surrounding waste disposal sites). 2) MaxEnt modeling delineated pronounced spatial heterogeneity in invasion risk. High and very high-risk zones, aggregating to approximately 852 km² (6.42% of the study area), are primarily concentrated in the western districts of Yibin, notably in Pingshan County, Xuzhou District, and Cuiping District. These high-risk areas demonstrate a strong spatial correlation with major river corridors, including the Jinsha River, Min River, and Yangtze River, as well as transportation networks. 3) The quantification of environmental variable contributions identified rivers and roads as the primary facilitators of Ageratina adenophora spread. Distance to rivers emerged as the strongest predictor, accounting for 25.1% of the contribution, followed by precipitation during the wettest quarter (18.7%), distance to roads (15.6%), and temperature seasonality (Bio4, 12.3%). Based on these findings, we propose a novel, integrated multi-scale management framework termed "eradication in colonized areas-monitoring in high-risk zones-public co-governance" to enhance intervention efficacy, scale-matching, and ecological compatibility: 1) Implement integrated mechanical-chemical control within existing growth areas and establish native vegetation buffer strips between different landscape types to impede spread. 2) Establish remote sensing monitoring networks in high-risk invasion zones, with particular emphasis on buffer areas along rivers and roads. 3) Promote public participation in the prevention and control of invasive alien species such as A. adenophora across the region through new media and other means. This integrated approach aims to mitigate the current and future impacts of this pervasive invader. This study provides a theoretical foundation and practical guidance for the effective control of Ageratina adenophora.