R/V Isabu-Based First Ultraclean Seawater Sampling for Ocean Trace Elements in Korea

Abstract

Trace elements (Mn, Fe, Co, Ni, Cu, Zn, etc.) are essential micronutrients for marine organisms and are thus related to major issues in the ocean, such as climate change, ecosystem change, and pollution. However, given their extremely low concentrations in seawater, contamination-free clean seawater sampling for trace elements onboard is the most crucial factor in this study. Because of the absence of both clean seawater sampling techniques and related infrastructure (e.g., a research vessel equipped with a nonmetal sampling system), the trace element community in Korea has not contributed to the global community studying trace elements in the ocean, although the associated global joint study program "GEOTRACES" has been operating for 10 years. With the newly launched research vessel (R/V) Isabu of the Korea Institute of Ocean Science and Technology (KIOST), Korea is now equipped with a large comprehensive R/V complete with a contamination-free PRISTINE ultraclean seawater sampling system for trace elements. We conducted clean seawater sampling 2 research cruises in the Indian Ocean during 2017-2018 aboard the R/V Isabu, and we successfully obtained reliable data, which agree well with previously reported trace element data at these locations. Here, we present the procedure and preliminary results of clean water sampling for trace elements based on the R/V Isabu, as the first Korean open ocean trace element study. From this study, we expect that R/V Isabu will play an important role in research on oceanic trace elements and isotopes in the future.