The influence of tree population structure on regeneration potential in the sacred forests of Assam, India

Sacred forests protected through nature beliefs have undergone successional stages to form the climax vegetation harbouring rich biodiversity. The study on the effect of population structure on the regeneration status of tree species is limited in the sacred forests. The present study was carried out in four sacred forests of Assam wherein 57 tree species belonging to 51 genera under 28 families were recorded. The correlation of girth class with species richness, density, and basal area of trees showed a significant negative relationship. One-way ANOVA on ranks proved a significant impact of girth class on the number of individuals of species, F(10) = 36.46, p < 0.05. A reverse J-shaped GBH-density distribution revealed that most species have higher individuals in lower girth classes (0-30 cm) with steady growth. The regeneration capacity of tree species in the sacred forests showed seedlings (741) > saplings (485) < adults (514). Putranjiva roxburghii Wall. and Bauhinia purpurea L. recorded as the dominant species having maximum density ha(-1) in the seedling stage. Overall, the regeneration of tree species showed maximum status in 'fair' followed by 'good', 'poor' and 'not regenerating' category. Sacred forests are privileged to have rich diversity; however, considerable changes due to environmental stress or interference exerted by human activities may distress the structural and functional composition of the forests.