著者

佐藤 麟太郎 奥村 真子 黄 国宏 長谷川 浩 三木 理

出版者

海洋理工学会

雑誌

海洋理工学会誌 (ISSN:13412752)

巻号頁・発行日

vol.27, no.1, pp.45-53, 2022-07-30 (Released:2022-08-27)

参考文献数

40

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Recently, a great interest has been observed in using marine species for coastal environmental impact assessment. Embryos of brown macroalga, Sargassum horneri, distributed throughout the northwest Pacific coast, appear be a promising marine indicator for such assessments. This study identified the effects of copper (Cu–EDTA) on the germling growth of S. horneri. Following exposure to various copper concentrations for 21 days, the germination rate, specific growth rate, and final thallus area of S. horneri germlings were measured. The germination of the embryo was completely inhibited when exposed to 10 µg/L, and the no observed effect concentration (NOEC) for germination was estimated as 5 µg/L. Since the incubation period was longer for lower copper concentrations, growth inhibition could be clearly observed and was deduced to be a chronic toxicity effect. The median effective concentration (EC50) and NOEC for the final thallus area were 0.50 and 0.16 µg/L, respectively. The results demonstrated that the embryos of S. horneri are more sensitive to copper than other seaweeds, further suggesting that its growth patterns can effectively be utilized to assess coastal environmental impacts.

著者

小畑 元 黄 国宏

出版者

一般社団法人日本地球化学会

雑誌

地球化学 (ISSN:03864073)

巻号頁・発行日

vol.56, no.3, pp.33-46, 2022-09-25 (Released:2022-09-25)

参考文献数

98

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Trace metals, like iron, copper, zinc and cobalt, in seawater are essential for phytoplankton growth and limit the primary production in some oceanic regions. It is crucial to reveal not only distributions of the metals but also their chemical speciation in seawater because their availability to phytoplankton depends on their speciation. At present, it is well known that more than 99% of iron and copper are complexed with organic ligands in seawater, which was revealed mainly by using voltammetry. In this review, we introduce the electroanalytical methods of organic ligands for trace metals in seawater. Moreover, we indicate the voltammetric methods to determine nanomolar levels of specific organic ligands for trace metals, such as humic substances and thiols, in seawater.