Algae. 1989; 4(2): 165-170.

Vertical Distribution of Several Species of Macroalgae (Phaeophyta) along the Coasts of Aomori Prefecture, Japan

Masahiro Notoya, Yusho Aruga

Laboratory of Phycology, Tokyo University of Fisheries

Standing crop of 14 species of macroalgae in Phaeophyta was measured at depths of 5,10, 15 and 20 m along seven transects on the coasts of Aomori Prefecture excluding Mutsu Bay. Each species showed a characteristic distribution pattern in its growing depth. Alaria crassifolia, Sargassum micracanthum and Cystoseira hakodatensis were growing in shallow water of 5-10 m, while Agarum cribrosum and Sargassum horneri were growing in deep water of 10-20 m. Other species were widely distributed at depths of 5-20m. Warm-current species, such as Ecklonia stolonifera, Sargassum siliquastrum and Myagropsis myagroides, showed that their growing depth became shallower as the limit of their horizontal distribution (Cape of Ooma) was reached. The coasts of Aomori Prefecture excluding Mutsu Bay can be divided into three sections according to the subtidal vertical distribution of these species; (1) the coasts from the Japan Sea side to Cape of Tappi, (2) the coasts from the Cape of Tappi to Cape of Ooma facing Tsugaru Channel, and (3) the coasts from Cape of Ooma to the Pacific side.

Keywords : Aomori Prefecture, macroalgae, Phaeophyta, seaweeds, standing crop, vertical distribution