Abstract: Phytoplankton are small, microscopic plants that live suspended in the open water. Phytoplankton are generally more abundant in lakes than rivers. Microorganisms are present in large quantities everywhere and can survive extreme physical and chemical conditions. Many microorganisms play foundational roles in aquatic ecosystems. They serve as a food and shelter of other aquatic organism especially zooplankton. Phytoplankton acts as a biological indicator of water pollution. The latitude of Kanwar Lake, Begusarai, India is 25.630383, and the longitude is 86.145172. The Plankton sample was collected at once from all three sites of Kanwar Lake in a monthly interval from January 2022 to December, 2022.The plankton sample were collected in sterile plastic bottles with the help of plankton net of mesh size 25 and diameter of pore 60μ. Phytoplankton material was preserved in 4% formalin solution at the site of collection. In the present research investigation, water body show variety of algal genera. Algal genera belong to groups Chlorophyta, Bacillariophyta and Myxophyta. Out of 13 Genera of Phytoplankton 5 belongs to Chlorophyta, 4 belong to Bacillariophyta and 4 belong to Myxophyta. The finding of results showed that all three sites of the lake found to be average and more or less similar. So, it clearly indicated that lake not shown much eutrophic due to a smaller number of pollutants are analysed in this study.

Keywords: Kanwar Lake, Phytoplankton, Zooplanktons

| DOI: 10.17148/IARJSET.2023.10598