Alterations in physico-chemical parameters of water and aquatic diversity at Maneri-Bhali phase I dam site on river ganges in district Uttarkashi, Uttarakhand

Abstract

Rivers and lakes comprise approximately 0.009 % of earth’s water but they harbour about 43 % of fish biodiversity (Nelson 2006; Helfman 2007). These fresh water systems also support various zoo-planktons and phyto-planktons which are important bio-indicators of an ecosystem. Greatest threats to freshwater ecosystems globally are: anthropogenic activities that cause habitat degradation, fragmentation, and loss; flow modifications; translocation of species outside their native ranges; over exploitation and pollution. Humans appropriate fresh water globally for direct consumption, crop irrigation, hydro-electric energy production and other purposes. The direct and indirect competition with humans for limited freshwater resources is largely why fishes and other aquatic organisms are among the most imperiled faunas on earth (Baxter 1977; Leidy and Moyle 1998; Duncan and Lockwood 2001).