SEASONAL SURVEILLANCE OF LIMNOLOGICAL PARAMETERS WITH RELATION TO ICHTHYOFAUNAL DIVERSITY IN A FLOODPLAIN LAKE OF WEST BENGAL, INDIA USING PRINCIPAL COMPONENT ANALYSIS AND COMPREHENSIVE POLLUTION INDEXT. CHAKRABORTY AND N.C. SAHAAbstract The health status of any aquatic body is directly dependent on its physicochemical properties. This present seasonal assessment was carried out to evaluate the correlation between limnological parameters and fish diversity, as well as Comprehensive Pollution Index of Nandannagar jheel, North 24 Parganas, West Bengal, during the tenure of March 2019 to February 2021. Water samples were collected on monthly basis at 4 stations of this jheel and limnological characteristic like pH, dissolve oxygen, carbon dioxide, turbidity, water temperature, total alkalinity, total hardness, phosphate, nitrate and biochemical oxygen demand are measured. The principal component analyses (PCA) result showed that pH (-0.864), total alkalinity (-0.799), dissolve oxygen (-0.900), and carbon dioxide (0.853) were the main factors. Significant (p < .05) negative correlations were recorded between water temperatures and dissolve oxygen, carbon dioxide and dissolve oxygen, while significant (p < .05) positive correlations were found between pH and biochemical oxygen demand, pH and dissolve oxygen. In respect of fish faunal diversity, a total of 28 species belonging to 6 orders and 15 families were identified. Maximum representatives belong to order Cypriniformes having 6 species with 38% catch composition, whereas Perciformes with 12 species with 28.55% catch composition. Both the Shannon Weiner diversity index (2.871-2.998) and comprehensive pollution index (0.53-0.61) indicate the water body of this jheel is moderately polluted. The study recommends constant monitoring is needed to minimize the anthropogenic activities surrounding this jheel. |