CONCLUSION

The analysis of different physico-chemical characteristics of water collected from the IISc Campus, Centenary pond, Bangalore showed a significant improvement of water quality owing to algal and duckweed uptake. The growth of algae and duck weeds accounted for ~45 % of nutrient removal. Furthermore indigenous algal consortia played important role in nutrient removal by their abilities to adapt and grow at variable nutrient regimes. A transition in nutrient uptake was observed during April, due to variability in the feed rate and higher sediment upwelling resulting in anoxic conditions. Initial cyanophycean members (Microcystis sp.) in the ponds were succeeded by chlorophycean (Chlorococcum sp.) members due to alterations in their bio-chemical environment. Thus with careful feed rate management and optimal algal group selection, secondary treated wastewaters can be economically treated and reused for domestic and other purposes.