Zooplankton population in relation to physico-chemical parameters of Lal Diggi pond in Aligarh, India.

Physico-chemical parameters and zooplankton were assessed Lal Diggi pond from January to December, 2008. Four groups of zooplankton were recorded. Rotifera constituted the main dominant group in this pond contributing 44.89% of the total zooplankton population followed by Cladocera (30.41%), Copepoda (15.51%) and Ostracoda (4.68%). The highest density of zooplankton was recorded during January and February being 197 and 182 no l(-1) respectively, while the lowest density was recorded during May and June being 64 no l(-1) each could be due to the negative and significant value of correlation between zooplankton and water temperature (r = -0.700). These data is supported by similarity indices which recorded high values during January and February while the lowest values recorded during June and July.