Status of zooplankton diversity, abundance in relation to hydrography of ganga river and its tributaries at Rishikesh

The Ganga River is one of the largest river in India and fifth longest river in the world. The river originates from the ice cave of oo Gaumukh (33 55'N, 79 07' E) at the snout of Gangotri glacier in the Garhwal portion of Western Himalaya, at an elevation of about 4100meters. During the present study different species of zooplankton ware recorded to access the present status of zooplankton population, their abundance and also its relation to water quality. Four important groups as Cladocera, Copepods, Protozoa and Rotifers mainly contributed to zooplankton population along the Ganges riverine system. The value of Shannon Weiner Diversity (H'), Evenness (J') and Simpson diversity indices indicated low to medium diversity of zooplanktons in the selected zones. Water temperature, water velocity and dissolved oxygen contributed as major influential ecological factors for zooplankton richness and their distribution in the Ganges riverine ecosystem.