Seasonal Abundance of the Zooplankton of Waste Water from the Industrial Complex at Birla Nagar (Gwalior), India

Zooplanktonic fauna of waste water from the industrial complex at Birla Nagar, Gwalior alongwith its seasonal abundance have been studied. In all, 16 species have been identified, viz. Arcella discoides, Lesquereusia modesta, Difflugia corona, D. muriformes and Acanthocystis spinibera under protozoa, Brachionus calyciflorus, Br. caudatus, Br. falcatus and Keratella tropica under rotifera, Daphnia (Daphnia) carinata and Daphnia (Daphnia) lumholtzi under cladocera, Cypris sp. and Cyprinotus qunninqi under ostracoda and Spicodiaptomus chelospinus and Mesocyclops leuckarti under copepoda. In their seasonal abundance members of protozoa showed the maxima in the month of April while the minima were observed in the month of July with an irregular trend of fluctuation. Rotifers, however, exhibited two maxima, one each during winter and early summer. Cladocera were maximum in February, while minimum in October. Ostracodes were maximum during May and June. Copepods were highest in the months of August and lowest in February. The total zooplankton population presented a clear-cut bimodal pattern of their seasonal fluctuation with the first peak appearing in the month of April and the other one in November. Lowest counts were obtained in the month of February. The zooplanktonic organisms belonging to rotifera were relatively abundant, followed by protozoa, copepoda, ostracoda and cladocera in a sequence.