Biological diversity of live food spectrum at Maa Chandrika Devisite in upstream of river Gomti in Lucknow (India)

An upstream location along the course of river Gomti in Lucknow, Maa Chandrika Devi, was identified for the present study. The water quality of the river at the site was moderate with mean DO 6.15 mgl⁻¹ whereas nitrate (22.70 mgl⁻¹), phosphate (2.40 mgl⁻¹) and COD (48.72 mgl⁻¹) were high. The high concentration of nutrients as well as COD during pre-monsoon may be due to low precipitation and influx of effluents during summer. Phytoplanktons were represented by Chlorophyceae, Bacillariophyceae and Xanthophyceae. Phytoplankton mainly contributed by Gonatozygon (10.89%), Closteridium (30%), Cladophora (34.94%) and Cosmerium (14.49%). Protozoa, Ostracoda, Rotifera, Cladocera, Copepoda, Diptera and Oligochaeta were the zooplankton phyla. The dominant zooplankton genera were Brachionus (13.38%), Daphnia (5.55%), Moinodaphnia (6.94%0), Cyclops (22.22%), Mesocyclops (11.11%) and Diaptomus (8.33%) apart from worms (8.33%). Benthic fauna was represented by Oligochaeta, Chironomus, Crustacea, Diptera, Odonata, Nematoda, Pelecypoda, Gastropoda and leech. Chironomus with contribution of 54.09% dominated the fauna. Other predominant groups were Oligochaeta (20.16%), Pelecypoda (16.57%) and Diptera (4.99%). In general, high population density of phytoplankton, zooplankton and benthos were encountered during premonsoon season. Low population of zooplankton compared to phytoplankton and increasing number of rotifers next to copepods and cladocerans as well as presence of protozoans indicated substantial load of organic matter. The organic pollution indicator benthic species like Branchiura, Tubifex, Chironomus, Cullicoid larvae (Diptera), Lamellidans, Corbicula, Lymnaea and leech also supported the polluted environment. Shannan-Wiener index of less than 1 for Diptera, Gastropoda and Pelecypoda indicated the stressed environment. Low abundance of plankton population in spite of high nutrient budget of the ecosystem was the function of great infestation of water quality which indicated extreme state of pollution.