Trace elements in surface sediments of Navarino Bay,Greece

The distribution of a number of trace elements in the Navarino Bay surface sediments is examined and their source and association with the major phases is determined. Cobalt follows Al in its distribution, having its highest vaues towards the center and deeper parts of the bay; Zn and Cu have their highest values at the effluent outfalls of a distillery and an olive oil and olive kernel factory (at the port of Yalova), being decreased away. The highest concentration of Ni is found near the town Pylos, while the highest concentrations of Rb and Y are observed at the mouths of rivers Yalovas and Xerias. Organic matter has its highest content at the port of Pylos, while no significant variations have been observed in the distribution of Sn and Ga. It is demonstrated that there is an anthropogenic input of Zn, Cu, and Corg in the bay. Zn and Cu are discharged by a distillery and an olive oil and olive kernel factory, at Yalova. Organic matter is mainly derived from domestic sewage. Ni enters the bay from its southern coasts and might be derived from weathering of bauxite deposits present in the adjacent limestones. Rb and Y are transported by the rivers Yalovas and Xerias from the northeastern adjacent land area; Ni, Co, and Cu show positive correlation with Al, suggesting their incorporation in clay minerals, while Rb shows positive correlation with Si, suggesting its incorporation in silicate detrital minerals. The following areas in the bay are considered to be heavily polluted: (1) the port and a large zone near Pylos (domestic sewage); (2) the port and a small area near Yalova (domestic sewage and industrial effluents); and (3) the eastern coast of the island Sphaktiria (oil). The domestic sewage pollution in Navarino Bay is of the same level as that in other Greek bays.