Year: 2009
Type: article
Abstract: Three selenium species, selenite, selenate, and organic selenide, were determined simultaneously in the eastern tropical, and subtropical South Pacific Ocean. Selenite shows a typical nutrient-like profile. Selenate also shows a nutrient-type profile. The highest correlation between selenite and silicate (r＝0.98～1.00, p＜0.00001) indicates that selenite is supplied from decomposition of selenite-silicate compounds in the hard tissue of phytoplankton. On the other hand, the correlation coefficient between selenite and nitrite＋nitrate (phosphate) is higher than that between selenite and silicate in the subtropical South Pacific Ocean. These results indicate that selenite is supplied from the decomposition of not only the hard tissue of plankton body but also the soft tissue. The organic selenide was detected in deep waters. This might be due to the presence of refractory selenium compounds such as selenium-humic acid complex. The selenite/selenate ratio in deep water is not necessarily decreased with increasing total selenium concentrations. This might be due to the irregular addition of selenium to deep waters via sinking particulate matter.
Authors: Yuzuru Nakaguchi, Yasunobu Mitsuhashi, Kenichi Kitahata, A. Fujita, Ayako Sumiyoshi, Yasuko Kawai
Language: English
Subfield: Oceanography
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Life below water
Open Access status: green
OpenAlex ID: W318108567