Vegetational Diversity in Submerged Hydro-Electric Project in the Eastern Himalaya

The study was conducted to assess the vegetation diversity and forest structure in and around the Dumbur Hydroelectric Project in the Lower Eastern Himalayan Region of Tripura, India. A nested quadrat design was used with slight modifications to assess plant diversity. A total of 221 plant species were recorded, of which, 112 were herb species (53 families), followed by 45 shrub species (20 families), and 64 tree species (26 families). The Simpson index (1–D = 0.83) and Shannon diversity (H = 2.15) reflect moderate taxonomic diversity, while the evenness (EH = 0.64) suggests that some shrub species are far more abundant than others. The diversity analysis showed a clear stratified pattern of species distribution and revealed gradient of decreasing diversity from herbs to shrubs to trees. This structure reflects ecological conditions that favour herbaceous species richness and suggests varying levels of disturbance, succession, or competitive interactions across vegetation strata in the study area. The vegetation of the study area is vital for sustaining the livelihoods of the local people, as most of the surrounding communities are forest-dwelling communities. This study calls for an urgent conservation initiative to conserve biological diversity, while ensuring food security, livelihood, and sustainable development.