Abstract
This study was conducted part of the GEOTRACES program to determine global ocean distribution of bioactive trace metals. Seawater samples were collected from the Japan Sea using the latest clean sampling technology. An analysis of bioactive trace metals were investigated by highly accurate instrumental analytical technology. An analytical method for bioactive trace metals in seawater was carried out using the commercial chelating resin solid phase extraction ICP-MS method. We checked the contamination during the column concentration process. We also checked the precision of the new analytical method by using the seawater reference material NASS-5. The analytical values agreed with the certified values. Dissolved Fe, Cd, Cu, Zn, Ni and Co were measured in the Japan Sea. Fe, Cd and Ni exhibited nutrient like profiles. The average concentrations of Fe below 2000 m at two stations were significantly higher than at the other sampling stations and the North Pacific deep water. It might be due to the difference in atmospheric iron flux from the mainland. Significant correlations were observed between Cd and nutrients. The correlation coefficients (r) between Cd and silicate were slightly higher than those between Cd and phosphate. This result confirmed that Cd is released from decomposition of both organic soft tissue and skeletal matter in the Japan Sea. The distribution and behavior of Ni is similar to those of Cd.
