, 2004). Urbanization exerts selleck products significant influences on the structure and function of wetlands,
mainly through modifying the hydrological and sedimentation regimes, and the dynamics of nutrients and chemical pollutants. Impact of urbanization is equally alarming on natural water bodies in the cities. A study found that out of 629 water bodies identified in the National Capital Territory (NCT) of Delhi, as many as 232 cannot be revived on account of large scale encroachments (Khandekar, 2011). Similarly, between 1973 and 2007, Greater Bengaluru Region lost 66 wetlands with a water spread area of around 1100 ha due to urban sprawl (Ramachandra and Kumar, 2008). Further, poor management of water bodies, lack of concrete conservation
plans, rising pollution, and rapid increase in localized demands for water are pushing these precious eco-balancers to extinction (Indian National Trust for Art and Cultural Heritage, 1998). Water in most Asian rivers, lakes, streams and wetlands has been heavily degraded, mainly due to agricultural runoff of pesticides and fertilizers, and industrial and municipal wastewater discharges, all of which cause widespread eutrophication (Liu and Diamond, 2005 and Prasad et al., 2002). As a result of intensification of agricultural activities over the past four decades, fertilizer consumption in India has increased from about 2.8 million tonne in 1973–1974 to 28.3 million tonne in 2010–2011 (Data
Source: Indiastat). As selleck chemical per estimates, Clomifene 10–15% of the nutrients added to the soils through fertilizers eventually find their way to the surface water system (Indian Institute of Technology, 2011). High nutrient contents stimulate algal growth, leading to eutrophication of surface water bodies. Studies indicate that 0.5 mg/l of inorganic Nitrogen and 0.01 mg/1 of organic Phosphorus in water usually stimulates undesirable algal growth in the surface water. Runoff from agricultural fields is the major source of non-point pollution for the Indian rivers flowing through Indo-Gangetic plains (Jain et al., 2007a and Jain et al., 2007b). Water from lakes that experience algal blooms is more expensive to purify for drinking or other industrial uses. Eutrophication can reduce or eliminate fish populations (Verhoeven et al., 2006) and can also result in loss of many of the cultural services provided by lakes. Along with runoff from agricultural fields, untreated wastewater also contributes significantly to pollution of water bodies. Less than 31% of the domestic wastewater from Indian urban centres is treated, compared to 80% in the developed world. In total of 35 metropolitan cities, treatment capacity exists for only 51% of the sewage generated.