Toxicologie environnementale et analytique

Zooplankton Composition and Community Structure of Kottakudi and Nari Backwaters, South East of Tamil Nadu

Abstract

K. Thirunavukkarasu, P. Soundarapandian, D. Varadharajan and B. Gunalan

Zooplankton plays an important role to study the faunal bio-diversity of aquatic ecosystems. It is occurrence and distribution influences the fishery potentials. The fishes mostly breed in areas where the planktonic organisms are plenty so that their young ones could get sufficient food for survival and growth. The zooplankton composition during the study period includes the members of Foraminifera, Rotatoria, Calanoida, Cyclopoida, Harpacticoidea, Doliolida, Appendicularia, Decapoda, Sagittoida, Amphipoda, Coelentrata, Pteropoda, Cladocera and larval forms. In station I, about 88 species of zooplankton were recorded. In station II, about 92 species of zooplankton were recorded. The zooplankton population densities were ranged from 23,150 to 80,890 org/l in station I and 23,197 to 80,691org/l in station II. The Shannon - Wiener's diversity index (H') values were ranged from 4,505 bits/ind. to 5,915 in station I and 4,590 bits/ind. to 5,928bits/ind. in station II. The Simpson richness was ranged from 0.662 to 0.995 in station I and 0.665 to 0.998 in station II. The Pielou’s evenness (J') was ranged from 0.590 to 0.952 in station I and 0.513to 0.952 in station II respectively.