Kolkata city's eastern side had a total wetland area of 81 km2 in 1945 with 47 km2 area sewage-fed fisheries that has been decimated today to 51 km2 of wetland area covering 12 km! fisheries area. Even after this 63% crunch of wetland area and nearly 26% reduction in aquatic system, east Kolkata wetland areas yield 11.4% of the total annual supply of fish for India. The pattern of available elements at the control site (bottom sediment) was Fe>Ca>Ti>Zr>Mn>Sr>Rb>Cr. At the contaminated sites, this pattern changed markedly.Pb was not detected from any of the contaminated sites and at the most contaminated site (site I), the availability of metals was recorded as Ca>Cr>Fe> Ti>Sr>Mn>Zn>Zr>Rb>Cu.
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