TRACE, ALKALINE AND ALKALINE-EARTH ELEMENTS IN SEA-WATER SAMPLES FROM TERRA-NOVA BAY ROSS SEA (ANTARCTICA) - A 3-YEAR PERIOD OF OBSERVATION

This report concerns the correlation of the analytical results relevant to some elements obtained in filtered sea water samples collected in Terra Nova Bay and the Ross Sea (Antarctica) during three Italian expeditions. The following ranges of variability of the medians of total concentrations (ng/l) - which include time effect among expeditions and bias effect among participant groups - were found for trace elements (single values refer to elements which were only determined once by one laboratory): Sb(260), As(1.2 10(3)), Cd(5-50), Cr(120), Co(4), Cu(110-230), Fe(435-445), Pb(6-52), Mn(15-88), Hg(3), Ni(185-580), Se(30) and Zn(242-265). Speciation studies pointed out that 10-40% of Cd, 15-60% of Cu and 20-50% of Pb were present in the samples as an ASV-labile fraction. As for alkaline and alkaline-earth elements, the following concentration ranges in surface sea waters, expressed in mM, were found: Li([1.4-3.0]10(-2)), Na(394-480), K(5.1-9.9), Ca (6.4-14.7), Mg (46.2-59.0) and Sr ([7.6-10] 10(-2)). Inter- and intra-laboratory data comparison, incorrect results, local variations of concentration, including pollution effects and pack melting effect, are discussed in detail.