Sujata Bedwal and R.N. Mathur
Abstract
In order to study the zooplankton population and physico-chemical characteristics of Kishangarh Lake of Rajasthan samples were collected monthly between 8 am and 11 am from October 2001 to March 2002 to work out various parameters such as water temperature, transparency, turbidity, pH, conductivity, TDS, total alkalinity, total hardness, calcium, magnesium, sodium, potassium, chloride, nitrogen-nitrate, phosphate, sulphate, DO, BOD and COD by using standard methods. Water temperature ranged from (15.92 to 25.62 oC), transparency (60.96 to 66.00 cm), turbidity (7.06 to 8.42 NTU), pH (7.72 to 9.04 Unit), conductivity (446.32 to 898.28 μ mhos/cm), TDS (312.48 to 604.32 mg/L), total alkalinity (167.34 to 354.02 mg/L), total hardness (162.96 to 217.88 mg/L), calcium (20.42 to 45.72 mg/L), magnesium (16.18 to 29.70 mg/L), sodium (70.94 to 93.74 mg/L), potassium (17.52 to 24.86 mg/L), chloride (124.84 to 188.96 mg/L), Nitrate-nitrogen (0.96 to 1.23 mg/L), phosphate (1.62 to 2.04 mg/L), sulphate (162.98 to 178.14 mg/L), DO (5.52 to 7.02 mg/L), BOD (16.72 to 19.46 mg/L) and COD (24.48 to 28.74 mg/L). Total of 43 zooplankton species were found belonging to 5 groups i.e. Rotifer (11 sp.), Cladocera (06 sp.), Ostracoda (04 sp.), Copepod (08 sp.) and 13 species belonging to Protozoa. The eutrophic condition of the lake is clearly indicated by the presence of pollution indicator species, viz. protozoans (Paramoecium caudatum, Oxytricha ovalis, O. oblongatus and Holophyra simplex) Rotifers (Brachionus calcyflorus, B. forficula, Keratella tropica and K. procurva) and copepods (Neodiaptomus schmackari, Mesocyclops leuckarti and M. hyalinus). Dominance of protozoa and rotifers indicated water quality deterioration and also exposed its eutorphics condition.