Distribution of dissolved trace elements in seawater using ultraclean CTD on the R/V ISABU from the East Sea, Korea

Abstract

In South Korea, the lack of infrastructure and experience for research in open ocean has made it impossible to contribute to GEOTRACES program. However, the Korea Institute of Ocean Science and Technology (KIOST) recently launched a large ocean research vessel (RV) ‘ISABU’. This is the first of the Korean research vessels to be equipped with seawater collection equipment for trace elements to avoid contamination. For ultra clean seawater sampling, ultra clean CTD system (NIOZ) is made of Titanium and 24 sampling bottles made of PVDF are used. Dissolved trace elements, especially metals, are very low concentration and are very sensitive to contamination, which makes sampling and analysis difficult. When usingUCC, it is necessary to thoroughly wash to produce data of contamination-free trace metals. Trace elements in the seawater were analyzed using an automated preconcentrated system (seaFAST sp3, ESI) with an inductively coupled plasma mass spectrometry (Nexion 2000, Perkin Elmer). The analytical results for 21 elements in this study show a good agreement to the certified values for the 5 types of CRMs (NASS-6, NASS-7, CASS-6, BCR505, and SLEW-3) in the range of 84 to 117%. Additionally, 9 rare earth metals were also in good agreement with reference values. The average concentration of Cu at the S4 was 116.9 ng/L, and the maximum value was about 1.4 times higher than the minimum value. Concentration of Cu did not