Diversity and Distribution Patterns of Invasive Alien Plant Species Along Dispersal Corridors in Parsa National Park, Central Nepal

Protected areas are vital for preserving native biodiversity, yet invasive alien plant species (IAPS) pose significant threats to their conservation. This study investigates how IAPS diversity varies across their dispersal corridors, such as road verges, riversides, seasonal springs, fire lines, and trekking trails, and examines the relationship between tree canopy openness and IAPS richness. We sampled 156 plots (2 m × 5 m) along these corridors in Parsa National Park (PNP), ensuring a minimum distance of 100 m between plots. Out of 10 IAPS recorded during the study, road verges and riversides were invaded by 70% of the recorded species, while the walking trail had the lowest number of IAPS (30%). The most prevalent IAPS was <i>Chromolaena odorata</i>, followed by <i>Mikania micrantha</i> and <i>Ageratum conyzoides</i>. One-way ANOVA indicated significant differences in IAPS richness among dispersal corridors (<i>p</i> < 0.001). Furthermore, IAPS richness increased with increasing tree canopy openness (<i>R</i> = 0.8, <i>p</i> < 0.001). Given that road verges and riversides appeared to be the major dispersal corridors of IAPS in the context of PNP, it is imperative to prioritize these corridors for IAPS monitoring, early detection, eradication, and control. Such efforts can reduce the establishment probability of new IAPS and mitigate the impacts of the widespread IAPS on the native species and ecosystems.