Ecological Patterns and Composition of Plant Diversity in Grasslands of Deccan Plateau, India

Abstract

Aims: The study investigates plant diversity and ecological patterns in the grasslands of Vikarabad district, Deccan Plateau, India, using quantitative and multivariate methods. Study Design: A total of 81 quadrats (1 m × 1 m) were laid across the study area. Species accumulation and rarefaction curves were generated using R (Vegan package) and PAST software to assess sampling adequacy. QGIS 3.14 ‘Pi’ version was used to map collection locations. Place and Duration of Study: The study was conducted in Vikarabad District, Telangana, during the post-monsoon season of 2019. Sampling was carried out across four geographically distinct forest zones: Damagundam, Parigi-Naskal, and Vikarabad Ranges, and Ananthagiri Hills. Methodology: Diversity was quantified using various metrics. Significance in difference in diversity across ranges was analysed using Dummy variable regression and Kruskal-Wallis test. Pairwise similarity in species composition was assessed using Jaccard Similarity Index. Pearson’s coefficient was computed to examine pairwise correlations among biotic variables. Site-level groupings were examined with Non-metric Multidimensional Scaling (NMDS). Statistical analyses were conducted using R, Python, and MS Excel. Results: A total of 125 taxa were documented, with only 12 taxa common across all zones, indicating low similarity in species composition. Heteropogon contortus was the most frequent and abundant species. Based on most diversity measures, Damagundam Range harboured the most diverse grassland community. Regression analysis and the Kruskal-Wallis Test showed statistically significant (P = 0.000) differences in mean and median diversity across the zones. Significant correlation was observed between biotic variables. NMDS grouped sites into two clusters based on abiotic and biotic variables. Conclusion: The study highlights the presence of diverse and two ecologically distinct zones in grassland community within Vikarabad district.