Abstract
Marine algal succession study was carried out on artificial reefs at the depth of 1m (the cobble bottom area), 4m (Eisenia bicylis-dominated area), and 8m (crustose corallines-dominated area) from October 1988 through December 1991 off Oshika peninsula, Japan. The nudations on the reefs were given at autumn, winter and summer. At the depth of 1 and 4m, algal successions during the studing periods were classified by dominant life-form groups into four phases: pioneer, small annuals and crustaceous algae; early sere, crustaceous algae; late sere, small perennials; climax, large perennials. Crustaceous algae-dominated phase continued owing to the high grazing pressures by herbi-vores at the depth of 8m. Changes in life-form groups from early sere to climax corresponded to the arrangement of algal communities from deeper zones to shallower zones.
