Krishna Prasad SharmaKhanal, Niraj2026-05-192026-05-192024https://hdl.handle.net/20.500.14540/26772The study assessed tree species diversity, regeneration, and the impact of invasive alien plant species in Sal and Riverine forest of Bhimwali Community Forest within south central Nepal. A total of 40 (20m×20m) plots, 20 plots in each forest type was laid by quadrate sampling method. Forest sampling was done in November 2022 and supplementary data were collected in November 2023. For data collection transects were drawn perpendicular to the river at 200m distance for each transect. In each transect 4 - 6 quadrats were laid. Minimum distance between each quadrat was 50m. Inside main plot sub-plot 5m × 5m was constructed for shrubs/saplings and 1m × 1m plot was conducted for herbs/seedlings respectively. From each quadrat all vegetation and plot characteristics were recorded. Altogether, 118 vascular plant species were recorded; 30 trees, 33 shrubs, 42 herbs, 7 ferns, and 6 climbers. Riverine forest has higher species richness than the Sal forest. In Sal forest 13 species of trees from 11 families were found, with Shorea robusta being the most dominant tree species with highest importance value index (IVI 212.33). In the riverine forest, 22 species of trees from 16 families were observed, with Trewia nudiflora as the most dominant tree species (IVI 100.76). The overall forest regeneration was relatively better in Sal forest in compared to Riverine forest with reverse J-shaped d-d curve. We observed that riverine forest has significant invasive plant impact than Sal forest. In the Sal forest, 9 invasive alien plant species were recorded, with Chromolena odorata having the highest frequency (80%), followed by Mikania micrantha at 75%. While in the Riverine forest, 11 invasive alien plant species were reported, with Mikania micrantha having the highest frequency (75%), followed by Chromolaena odorata at 55%. We have observed that the Riverine forest, being close to human settlements, experienced higher anthropogenic activities, leading to increased plant invasion and a direct adverse impact on forest regeneration. In contrast, the Sal forest exhibited better regeneration and lower instances of plant invasion in compared to the Riverine forest. The observed variations highlight the need of targeted conservation efforts in Riverine forest, especially in areas susceptible to human-induced disturbances. Addressing these challenges is crucial for sustaining the ecological balance and biodiversity of Bhimwali Community Forest in the coming years. Keywords: Community forest, Tree diversity, IAPS, Shorea robusta, Trewia nudiflora.en-USShorea robustaCommunity forestThesis