Seasonal variation of major elements (Ca, Mg) and trace metals (Fe, Cu, Zn, Mn) in cultured mussel Perna viridis L. and seawater in the Dona Paula Bay, Goa

The major elements and trace metals were analysed from mussel tissue and th e seawater taken from three depths (0,5 and 9 meters) from the culture site . Range of variation in Ca, Mg, Fe, Cu, Zn and Mn were 226-399; 708-1329; 0 .005-0.084; BDL-0.042; 0.01-0.0375; BDL-0.0099 ppm in the water medium and 1124-1950; 984-4783; 1862-8261; BDL-39; 133-1766 and 44-179 mu g/g dry wt i n the mussel tissue respectively. The major elements displayed seasonal var iation with low values during monsoon period in the water. Among trace meta ls, Zn and Mn seem to follow almost a close relationship in their contents in the mussel tissue and the water. An inverse relationship of Zn, Mn and C u to some extent was observed with size in the cultured mussels.