Population structure and regeneration status of tropical dry forests in Barnawapara Wildlife Sanctuary, central India

Yadav, Piyusha

PROCEEDINGS OF THE INDIAN NATIONAL SCIENCE ACADEMY

2026

Singh, L;Chaturvedi, RK

Forest regeneration is influenced by stand structure, species composition, and the availability of mature seed-producing trees. Regeneration potential is an indicator of forest health and the building blocks for future stands. The regeneration ecology of species varied as per their ecological tolerance because a species' capacity to reproduce and grow depends entirely on its tolerance limits, compatibility with site factors, seed source, and quality. The present study aims to evaluate the population structure and regeneration status of tropical dry forests in the Barnawapara Wildlife Sanctuary, Chhattisgarh, India. The assessment was conducted across five sites, viz., sal forest, mixed forest, natural teak, teak plantation, and Maniram teak plantation. At each site, ten randomly distributed 10 & times; 10 m quadrats were established within a representative 1-ha plot. The regeneration status of tree species was evaluated by comparing relative abundance of seedlings, saplings, and mature trees. Based on this comparison, regeneration was classified under five categories: good, fair, poor, none, or new. The population structure was analysed through girth at breast height (GBH) distribution and life-stage analysis. In addition, the relationship between woody species density and GBH was examined using exponential and logarithmic models. Results revealed that Sal (Shorea robusta) and teak (Tectona grandis) exhibited adequate regeneration across all sites with expanding or stable population structures, while teak plantations displayed a declining size-class distribution. Although teak exhibited adequate regeneration based on seedling-sapling abundance, plantation stands showed declining size-class distributions, likely reflecting stand management rather than regeneration failure. In contrast, several associated species showed poor or no regeneration may be influenced by overexploitation, grazing, and other anthropogenic pressures. At the site level, good regeneration potential was observed in 5 species (33.33%) at Site-1, 3 species (15%) at Site-2, 3 species (33.33%) at Site-3, 3 species (60%) at Site-4, and 2 species (50%) at Site-5. Natural forests displayed balanced GBH distributions, with most individuals in smaller girth classes, while plantations showed either younger regenerating stands (Site-4) or mature tree dominance (Site-5). Interrupted regeneration in certain species highlighted the probable influence of climatic variability and bio-edaphic factors. The exponential relationship between woody species density and girth class (R2 = 0.78-0.92) indicated ongoing regeneration with high turnover. Although key timber species are successfully regenerating, many indigenous species face regeneration failures, threatening their future existence or natural recovery, biodiversity, and ecosystem sustainability. Findings indicate that reducing anthropogenic disturbance and promoting mixed-species regeneration may help sustain biodiversity.