Temporal changes in plankton diversity in relation to hydrographical characteristics at Perumal Lake, Cuddalore District, Tamil Nadu, India

Abstract

The fresh water environment supports the productivity of phyto- and zooplankters and fin and shell fishes. The rate of fish productivity of an aquatic ecosystem solely depends on the rate of plankton productivity, and which in turn critically depend on the concentration and variation of hydrographical features. The current investigation was focused on the distributional pattern of phyto- and zooplankton vis-à-vis physicochemical characteristics in Perumal Lake, Cuddalore District, Tamil Nadu State (India). The hydrographical factors and phytoplankton as well as zooplankton diversity were studied at the monthly interval of 12 months by following the standard methods in freshwater of Perumal Lake from September 2018 to August 2019. Presently a total of 15 species of phytoplankton and 15 species of zooplankton were recorded in Perumal Lake. The present study reveals good variation in the hydrographical characteristics, such as temperature (24.2–30.1 °C), turbidity (10.4–43.2 NTU), total suspended solids (300.2–1800.8 mg/L), conductivity (3.25–10.54 mhos/cm), pH (6.92–8.2), total hardness (8.58–23.8 mg/L), dissolved oxygen (2.8–7.26 mg/L), dissolved carbon dioxide (0.96–13.2 mg/L), chloride (1.92–23.8 mg/L), nitrate (0.28–3.18 mg/L), sulphate (1.1–8.2 mg/L) and phosphate (0.19–3.34 mg/L). The findings of the present study indicate that the temperature has influence on phytoplankton as well as zooplankton diversity of species. Regular monitoring of hydro-biological parameters is necessary to assess the health of the lake ecosystem.