Comparative behaviour of toxic metals in a marine ecosystem

Tapes decussatus, which has economic importance, is found mainly in three localities only of Izmir Bay, Turkey: Cakalburnu Fishery, Deniz Bostanli and Tuzla. The animals are most abundant in Cakalburnu Fishery and Deniz Bostanli, but are rare in Tuzla. These localities are the inward extensions of the sea and are shallow. It is assumed that analyses of the Tapes decussatus can give useful information on the accumulation and distribution of trace elements and their isotopes. Field and laboratory experiments have been carried out to see how concentrations and distribution within the organism vary according to size, locality, and season of the year. Concentrations of copper, manganese, zinc, iron, cobalt, lead and mercury in samples were collected from the three localities, representing different environmental conditions. A comparison of the concentrations of copper, manganese, zinc, iron, lead, cobalt, mercury in the tissues and the organs of the animals has been made and the seasonal variation of each has been determined for each locality. (author)