Poll Res. 24 (1) : 243-246 (2005) Copyright © Enviromedia CRUSTACEAN COMMUNITY STRUCTURE OF MAHI RECEIVING INDUSTRIAL EFFLUENT ADITI NANDA, K.D. VACHHRAJANI* AND P.C. MANKODI Toxicology Division, Department of Zoology, Faculty of Science, M.S. University of Baroda, Vadodara 390002, Gujarat, India. ABSTRACT Mahi river (Mahi Sagar), one of the perennial rivers of Gujarat, flows around 12 km from Baroda. It receives treated and even raw industrial effluent from petroleum, petrochemicals, organo- chemical, dyes and other chemical industries. Aquatic pollution over the years has adversely affected the biota of Mahi river. Present study reports crustacean community structure in the river. A total of thirty crustacean species were identified from the samples and their seasonal occurrence and distribution was studied. The crustaceans were dominated by copepods and cladocearns. Highest density observed was that of Moina sp. at site 1. Variations were noted in the distribution of crustaceans of different sites, however no significant effect of pollution could be identified. INTRODUCTION Mahi river is one of the perennial rivers, which flows around 12 km from Baroda city. Most of the industries are situated on the southern bank of the river while a thermal power station is situated on the northern bank at Dhuvaran (Fig. 1.). An effluent channel from the industrial area heads towards the estuarine end of river and discharges the effluent in Ul'LVUT CIlAPD. Mahi river near Sarod in Bharuch district (Fig. 1). It 43 t:N contains treated industrial effluent from various small and large industrial units. During high tide Fig. 1. Showing the route of effluent channel. these effluent are taken upstream and thus pollute the entire estuarine region. A small tributary, Mini MATERIALS AND METHODS river flows through the industrial area and meets Mahi river near Sindrot, which is located in the Site of study: Three sites were selected from upper upper estuarine region (Fig. 1). Mini river is usually estuarine region for the study laden with raw industrial effluent and thus further Site I: Area where Mini river meets Mahi river. pollute Mahi river. (Sharma, 1995). The faunal Site II : Located around 1.5 km upstream of site 1. diversity studies of streams and river were greatly Site III : Located further around 1.5 km upstream neglected in parts of Gujarat, where riverine of site II and was almost beyond the estuarine pollution is extensive (Pilo and Pathak, 1996). region (upper tidal influenced zone) and thus Therefore an attempt was made to study having status comparable to freshwater condition. zooplankton diversity of few sites of Mahi river. Sampling Procedure: Surface sampling was done *Corresponding author, e-mail: kauresh123-zoo@msubaroda.ac.in