Distribution of Periphytic and Macroalgae in Periyar River, Kerala (India)

Algae play a vital role as primary producers in aquatic ecosystems, and understanding their diversity is crucial for ecosystem functioning. The present study conducted in the Periyar River, Kerala, presents a comprehensive exploration of periphytic and macroalgal communities. Over three years (2018-2020), algal samples were collected during different seasons, revealing 317 taxa from 132 genera. Green algal groups, particularly <i>Zygnematophyceae</i> and <i>Chlorophyceae</i>, were dominant, along with<i> Bacillariophyceae, Cyanophyceae</i>, and <i>Euglenophyceae</i>. The study unveiled seasonal variations and regional distinctions in algal composition, reflecting the dynamic nature of this ecosystem. Furthermore, this paper discusses the thallus organization and substrate preferences of these algae, providing valuable insights into their ecological roles and adaptability in the Periyar River, ultimately contributing to a deeper understanding of this vital aquatic ecosystem.