Temporal Variations of Seaweed Biomass in Korean Coasts: Munseom, Jeju Island

Abstract

Seaweed biomass was estimated using a nondestructive method in the rocky subtidal zones in Munseom, Jeju Island, Korea from July 2006 to April 2008. Seasonal samplings were done at the depth of 1, 5, 10 m using 50 x 50 cm quadrat. Mean biomass was comprised of 2,784 g wet wt m -2 and the biomass values varied seasonally from 1,176 g wet wt m -2 to 4,217 g wet wt m -2 with the highest point in April. Biomass reached maximum at 5 m depth in spring, but was shifted to 10 m depth in summer. Common seaweeds appeared year round in Munseom were Codium minus, Ecklonia cava, Sargassum spp., articulated corallines and Plocamium telfairiae. Among them, E. cava showed the highest biomass (average of 1,288 g wet wt m -2 ), comprising 48% of total biomass. Only 12 species' biomass covered 98% of total value, which indicated the contribution of few common species to algal community. Seaweed biomass in Munseom represented one of the highest values in coastal regions in Korea.