DISTRIBUTION PATTERNS AND DIVERSITY OF PERIPHYTON COMMUNITY IN THE GLACIER FED STREAM BALKHILA AT TILFARA FROM GARHWAL HIMALAYA

The present study aims to assess the distribution patterns, density, diversity and ecology of periphyton community in the Balkhila stream which is a glacier fed tributary of the Alaknanda river in Chamoli district of Uttarakhand. Periphyton are the algal communities attached to various submerged objects and contribute as food for zoobenthos and nektonic communities as well as a primary producer in an aquatic ecosystem. Population structure of the stream was represented by total 16 periphytic genera belonging to 3 classes viz., Bacillariophyceae (Cymbella, Navicula, Fragilaria, Nitzschia, Amphora, Diatoma, Synedra, Tabellaria, Cocconeis and Meridion), Chlorophyceae (Chlorella, Ulothrix, Zygnema Oedogonium and Spirogyra) and Myxophyceae (Phormidium). Bacillariophyceae emerged as dominating periphyton class throughout the year. Shannon- Wiener diversity Index and Margalef Index depicted that winter months were more conducive for the growth of periphyton. The multivariate SIMPLER test was performed to show the dissimilarity of periphyton. The multivariate cluster analysis among seasons was also performed. To study the abundance and distribution of periphytic communities in relation to various abiotic factors on seasonal basis, the multivariate canonical correspondence analysis (CCA) was performed.