Tree diversity and community characteristics of a tropical moist deciduous forest of Assam, India

The plant species composition, diversity and regeneration are critical in affecting forest health and are important for the conservation of forest ecosystems in any area. The present study was done in Gotanagar Reserve Forest (GRF) of Kamrup Metropolitan district of Assam, India in the year 2020–2022 by laying 25 quadrats of 100 m2, 50 quadrats of 25 m2 and 75 quadrats of 1 m2 for trees, saplings and seedlings, respectively. A total of 39 species belonging to 34 genera and 20 families were recorded in the study. Total tree density was 1008 stem ha−1, with maximum tree density contributed by Gmelina arborea (80 stem ha−1). Total basal cover (TBC) of trees was found to be 71.74 m2 ha−1, with maximum basal cover occupied by Schima wallichii (7.88 m2 ha−1). Gmelina arborea (IVI = 20.65) showed the highest dominance followed by Shorea robusta (IVI = 18.16). Shannon–Wiener diversity index, Simpson’s index, Margalef’s species richness and Pielou’s species evenness index for trees were recorded to be 3.50, 0.03, 6.87 and 0.96 respectively. The majority of the tree species (92.31%) showed a contagious distribution pattern, and only 7.69% showed random distribution. The majority (71.79%) of tree species showed good regeneration status, 15.38% showed fair regeneration status, 7.69% showed poor regeneration status and 5.13% showed no regeneration at all. The findings revealed that GRF is rich in tree species composition with good species richness and diversity. However, effective conservation and management initiatives are needed for the species under not regenerating category to conserve the vegetation and health of the forest.