Title: Water Quality Analysis of the Coastal Regions of Sundarban Mangrove Wetland, India Using Multivariate Statistical Techniques

abstract

Rivers are among the most vulnerable water bodies to pollution because of their role in carrying municipal and industrial wastes and run-offs from agricultural lands in their vast drainage basins. Detailed hydro-chemical research is needed to evaluate the different processes and mechanisms involved in polluting water (Helena et. al., 1999). Furthermore, due to temporal and spatial variations in water qualities, monitoring programs that involve a large number of physicochemical parameters and frequent water samplings at various sites are mandatory to produce reliable estimated topographies of surface water qualities (Dixon & Chiswell, 1996). The results are usually compiled into a large data matrix, which requires sophisticated data interpretations (Chapman, 1992). Water quality monitoring has one of the highest priorities in environmental protection policy (Simeonov et al., 2002). The main objective is to control and minimise the incidence of pollutantoriented problems, and to provide water of appropriate quality to serve various environmental purposes. The quality of water is identified in terms of its physical, chemical and biological parameters (Sargaonkar & Deshpande, 2003). The particular problem in the case of water quality monitoring is the complexity associated with analysing the large number of measured variables (Saffran, 2001). Belonging to the class of a tide-dominated wetland (Selvam, 2003), the Sundarban wetland is comprised of a complex network of estuaries, tidal inlets, tidal creeks and a large number of islands. Most of the creeks act as the pathway for the to-and-from movement of tidal water and downstream flow of river systems. The present day sedimentation of the GangaBrahmaputra systems (with average water discharge of 970 km3/y and average sediment discharge of 900-1200 x 106 t/y) is strongly influenced by the wet summer monsoon covering only 4 months of the year when about 80% of the Ganga discharge (300 x109 m3/y of water and 520 x 106 t/y of sediments) is contributed to the delta (Goodbred et al., 2003). The balance between freshwater and salt water in this wetland has been suffering modifications from the tilting of the G-B delta toward the east and rising sea level. Increased anthropogenic influences like withdrawal of river water from the upstream region and increase in organic and inorganic pollutants have further led to deterioration of health of the wetland