Chemical Oceanography of Harbour and Coastal Environment of Visakhapatnam (Bay of Bengal): Part I- Trace Metals in Water and Particulate Matter

Abstract

Concentrations of Fe, Mn, Cu, Ni, Zn, Pb, Cd and Co in surface and bottom water are higher in dissolved and particulate forms in the harbour as compared to their concentration levels in coastal waters. This may be attributed mainly to the discharge of industrial effluents and domestic sewage into the harbour. Though the trace metal concentrations in coastal waters of Visakhapatnam are higher than the average values of Indian Ocean, they are however, lower than those reported for coastal and inshore waters of Bay of Bengal. The dissolved trace metals, in general, show relatively higher values in monsoon whereas the particulate fraction shows higher values in post/premonsoon seasons. Significant correlations are observed between some dissolved and particulate trace metals, total suspended matter (TSM), and chlorophyll a indicating their common association with these fractions.