Seasonal variations in iodine concentrations in a brown alga (Ecklonia cava Kjellman) and a seagrass (Zostera marina L.) in the northwestern Pacific coast of central Japan

Abstract

Seasonal variations in iodine concentrations were investigated for two years in a brown alga (Ecklonia cava Kjellman) and a seagrass (Zostera marina L.) occurring in the northwestern Pacific coast of central Japan. The iodine concentration in E. cava was 0.92–5.6 mg per gram dry weight (g‒ 1 DW) (mean ± SD:2.3 ± 1.1 mg g‒1 DW), and its variation was similar to that of other brown algae. In Z. marina, the iodine concentration was 17–110 μg g‒1 DW (61 ± 28 μg g‒ 1 DW) and displayed seasonal variation, as it was high in winter and spring and low in autumn.