Variations in tree species diversity and population dynamics in edges to interior habitats of a tropical semi-evergreen forest at the foothills of Eastern Himalayas
摘要
The present study was conducted between year 2023 and 2024 to study variation in tree species diversity and population dynamics of edge (EH) and interior (IH) habitats of a tropical semi-evergreen forest at the foothills of Eastern Himalayas by using random quadrat method. Altogether, 49 species of trees were recorded from the study sites, however, IH (38 species) had higher tree species than EH (35 species). The total tree density, total basal cover and Margalef’s richness index were higher in IH (500.00 stem ha−1, 367.86 m2 ha−1 and 7.43, respectively) than in EH (433.33 stem ha−1, 56.34 m2 ha−1 and 6.47, respectively). However, Shannon Weiner’s, Simpson’s and Pielou’s evenness indices were better in EH (3.15, 0.05 and 0.95, respectively) than in IH (3.08, 0.08 and 0.88, respectively). Similarity of tree species between the habitats was 55%. However, based on Hutchenson’s t-test, the habitats were not significantly different (P < 0.05) in terms of species diversity. Majority of tree species (≥ 85%) displayed contagious distribution in both the sites. Of the top five IVI tree species of each study sites, only one tree species in each study site showed good regeneration. Exploitation of trees for timber and NTFPs by the local villagers were observed in both sites. EH was disturbed and degraded due to various natural and anthropogenic pressures. The disturbance was amplified by ongoing dam construction. All these biotic and abiotic factors together pose a major threat to the forest sustainability and existence.