Disparities in species diversity, community characteristics, and carbon stock of trees along the edge-interior gradient of Fatasil Reserve Forest, Assam, India.

The present investigation evaluates disparities in species diversity, community characteristics, and carbon stock of trees along the edge-interior gradient of Fatasil Reserve Forest (FRF), Assam, India. FRF was divided into two habitats, viz., edge habitat (EH) and interior habitat (IH). Stratified random quadrat method (altogether 1050 quadrats of different sizes) was employed for quantitative analysis. Biomass and carbon stock were estimated employing an allometric formula. Tree species composition, density, total basal cover (TBC), Shannon-Weiner diversity index, and Margalef's species richness index were higher in IH (38 species, 1460 stem ha⁻1, 84.41 m2 ha⁻1, 3.49, and 5.29, respectively) compared to EH (22 species, 1093.33 stem ha⁻1, 50.05 m2 ha⁻1, 2.90, and 3.13, respectively). However, Simpson's index and Pielou's species evenness index were higher in EH (0.07 and 1.07, respectively) than in IH (0.04 and 1.04, respectively). Tree communities between the habitats differed significantly (p ≤ 0.01) regarding species diversity. IH (9.25%) was less disturbed than EH (38.69%). Total biomass (TB), total carbon stock (TCS), and CO2 equivalent were greater in IH (1023.62 Mg ha-1, 511.81 Mg C ha-1, and 1878.34 Mg ha-1, respectively) than in EH (535.86 Mg ha-1, 267.93 Mg C ha-1, and 983.30 Mg ha-1, respectively); however, the variations were not significant (p ≤ 0.01). TCS differed significantly (p ≤ 0.01) among diameter at breast height (DBH) classes, with maximum in 20.1 - 30 cm class in both habitats. The study underscores the ecological significance and carbon sequestration potential of IH and emphasizes the need for targeted management interventions in EH.