Abstract

We have carried out this study to characterise the physic-ochemical properties of the tannery effluents at different treatment tanks and to identify if any aerobic planktonic forms are thriving in the toxic effluents. Pearson correlation matrix suggests significant positive correlation between pH and TSS, acidity, Pb and Cr. A significant positive correlation between TDS, EC and salinity is also recorded. The concentrations of six metals, namely, Cr, Pb, Cu, Zn, Mn and Fe are well within the safe limits. Principal Component Analysis, a dimension-reduction tool, shows that out of seventeen physicochemical variables, fourteen variables contain most of the information to influence the biota. Canonical Correspondence Analysis plot strongly suggests that the physico-chemical factors significantly influenced the occurrence of phytoplankton in treatment sites of CETPs. This work addressed the basic study questions, whether any oxygen liberating life-form is thriving in the treatment tanks that could be used in biological amelioration of toxic tannery effluents! We record the occurrence of three species of Cyanophyceae, one species under Chlorophyceae, two under Euglenophyceae and a single Bacillariophyceae in the treatment tanks extending an opportunity for further researches on the efficiency of these algal species in ameliorating different toxicants in the tannery wastewaters.