Anthropogenic Impact on the Lakes Ecosystem in Hi-Tech City, Bangalore, Karnataka

Lakes and other freshwater bodies recharges underground water table, cooling of the ambient air and reducing heat in the surrounding areas of the city. Anthropogenic activities and discharge of untreated industrial effluents and sewages into lakes has been monitored from past five years. The results are very evident showing depletion in oxygen level, high level of chlorophyll ‘a’, TDS, BOD, phosphates, sulphates, ammonia and high alkalinity (pH 9.2) etc., which inturn has altered the nutrient concentration contributing to the formation of algal blooms causing high mortality of fishes in and around the lakes of Bangalore. Diversity of phyto and zoo-plankton showed a declining and again an increasing trend depending upon the pollutant load in the water bodies taken for research study, which inturn affected the growth and reproduction of indigenous and exotic fishes present in these lakes. Satellite imageries and information available with Survey of India indicates that most of the2700 lakes in Bangalore Metropolitan Region have dried up. Over the years, Urbanization has claimed some of the lakes. Karnataka is among the priority area under a pioneering project to conserve lakes in the country. National River Conservation Directorate, Ministry of Environment and Forest (MoEF) and National Lake Conservation Plan (NLCP) aim at an integrated approach to restore and protect lakes. Signs and consequences of human activity is found everywhere on the earth. This paper discusses restoration, post-restoration and management strategies through a holistic approach based on the findings of pilot studies in Bangalore city, Karnataka State, India. Further details about the impact of aquatic pollution on lake environment and its fauna will be discussed in detail in the paper.