Rashmi Kumari and Arvind Kumar
Abstract
Present paper deals with the diversity of phytoplankton in lower stretch of Kosi River at Bhagalpur and Katihar districts of North Bihar. Bacillariophyceae contributed more towards the percentage composition of different groups of phytoplankton at all sampling research sites, followed by Chlorophyceae, Cyanophyceae, Euglenophyceae and Dinophyceae. Phytoplankton percentage composition and density was highest in Bacillariophyceae in Kosi river. The phytoplankton percentage composition is composed of Bacillariophyceae 64.52% to 43.69% (2017) and 80.97% to 42.6% (2018), Chlorophyceae 36.92% to 18.82% (2017) and 48.65% to 5.22% (2018), Cyanophyceae 33.9% to 12.31% (2017) and 25.64% to 4.15% (2018), Euglenophyceae 0.85% to 1.98% (2018) and Dinophyceae 0.68 % (2018). The present study has generated scientific and authentic base line data in the north Bihar of Kosi river water quality and phytoplankton composition, density, species diversity, evenness and richness during 2017-2018 on seasonal basis (winter, pre-monsoon and post-monsoon).