Species composition, vegetation structure and diversity of Sal (Shorea robusta Gaertn.) forests across different management systems in Central Himalaya, India

Sal forests are vital ecosystems in the Central Himalayas, including the Uttarakhand foothills, but have received limited research attention regarding vegetation characteristics under different management practices. This study addresses the knowledge gap by investigating the floristic composition, species diversity, and dominance patterns of Sal forests under different management practices. Sampling was conducted over a two-year period from 2022 to 2024. The data indicate substantial differences in vegetation characteristics of Sal forests between ANR (Assisted Natural Regeneration) and non-ANR sites. Shorea robusta was dominant among trees, Viburnum cylindricum among shrubs, and Ficus hederacea among climbers across both sites. However, the dominant herb species differed, with Oxalis corniculata dominating in ANR and Chromolaena odorata in non-ANR. Diversity indices showed higher species diversity in ANR, with Shannon–Wiener index values ranging from 0.86 to 3.21 and Simpson’s diversity index from 0.38 to 0.89. IVI analysis revealed that the ANR site had higher IVI values compared to non-ANR. Principal Component Analysis (PCA) identified PC1 (83.23%) and PC2 (15.40%), which separated the life forms. This study indicates that effective conservation strategies like ANR are essential for preserving Sal forests and their associated species, thereby enhancing biodiversity.