Trace metalsnutrient salts relationship in coastal seawater of Alexandria  <B>Trace metalsnutrient salts relationship in coastal seawater of Alexandria</B><P>H.I.Emara, M.A. Shiradah, Th.H. Moustafa and M.S. ElDeek</B><I><P> National Institute of Oceanography and Fisheries, Kayet Bey, Alexandria, Egypt</I><P> Abstract<P> Sea water samples, collected from the Eastern Harbour (EH) and ElMex Bay of Alexandria City during the period from November 1987 to January 1989, showed that the variations of the concentration of metals, especially Co, Ni and Cr in ElMex Bay as well as Ni and Cr in EH are obviously related to seasonal variations of the seawater density ('sigma't). During colder months, the water column of the EH is concentrated with Ni and Cr. Manganese, iron and zinc showed analogous behaviour to Ni and Cr but with a decrease in concentration during November 1988 instead of the increase. At ElMex Bay, where the density of water is lower by 6.9 than the average values of EH, the peaks of metals Co, Ni and Cr as well as 'sigma't were shifted to April. Phosphate showed similar behaviour to 'sigma't but with two peaks in February and June. During Warmer months (AugustSeptember) the metal content in both areas decreased to minimum. The normal relationship between micronutrients and trace metals Mn, Cu, Ni, Zn and Cr holds well for the sea water of the Eh and to a less extent ElMex Bay and it is obvious that there is a trace metalsphosphate covariations and a linear regression equations were estimated. Organic phosphorus also showed significant good correlation with Fe, Mn, Co and Cr, as well as Fe and Cu. Concentration of trace metals versus salinity showed a decrease of Fe and Mn when moving from low to higher salinities. In contrast, Cd and Pb showed higher concentrations at higher salinities which may be attributed to the release of these elements from bottom or suspended sediments. Phosphate and nitrate reflect higher levels at low and intermediate salinities. The daily contribution of trace metals and nutrients in kilograms that fluxes to the sea at ElMex Bay were estimated as: 867, 376, 107, 38, 10, 2.8, 2.6, 2.5, 1.3, 9140, 26308, 878 for Fe, Zn, Mn, Cu, Cd, Pb, Cr, Ni, Co, phosphate, organic phosphorus and nitrate, respectively.<P>