An Ecological Study on Resources of Marine Plants in Geomundo Islands

Algae > Volume 5(1); 1990 > Article

Algae 1990;5(1): 1-37.

Nam-Pyo Koh

Department of Aquaculture, Yosu Fisheries College

ABSTRACT

This study was carried out to understand the floral composition of marine plants and its community structure at Geomundo Islands, southern coast of Korea. As results, including previous reports a total 230 species, 3 blue-green, 142 red, 59 brown and 26 green algae, were indentified in this study. Among them, Hypnea boergesenii Tanaka. Pleonosporium yagii (Yamada) Norris, Chondria lancifolia Okamura and Lomentaria pinnata Segawa were reported for the first time in Korean marine flora. The occurrence of tropical and subtropical species were regarded to suggest that Geomun Islands were much influenced of Kuroshio warm current. A cluster analysis on the basis of species occurrence implied that the seasonality of marine plants was much different among the sampling sites. In comparison of R/P and C/P values, the Geomundo flora was similar with Chujado. The dominant species from importance value were Sargassum thunbergii and Corallina pilulifera in spring, C. pilulifera in summer, and C. pilulifera and Gigartina intermedia in autumn. The analysis of functional-form groups showed that the coarsely branched form and thick leathery form occurred 10-14% more at Dongdo and Godo, Closed areas, whereas they occurred relatively low at Seodo, an exposed area. The mean biomass was 93.89-209.97 g/m super(2)-d.w the greatest, 507.29g/m super(2)-d.w among the surveyed sites. The biomass of Geomundo was the highest among areas investigated in southern coast of Korea. The vertical zonation of marine vegetation in Geomundo Islands represented the characteristics of Cheju section, showing Gloiopeltis spp. -Gelidium divaricatum at upper littoral zone, Ishige spp. -Hizikia fusiformis -Sargassum thunbergii -Corallina pilulifera at middle littoral zone, Dictyopteris divaricata - Gigartina tenella, Laurencia intermedia, Hypnea charoides in lower littoral zone, and Ecklonia cava and Sargassum horneri in sublittoral zone. The peak of coverage and biomass moved into the lower part at littoral zone from spring to autumn, which suggested the change of environmental factors in season had much influence on the marine plant community. The economic plants in Geomundo were Undaria pinnatifida, Meristotheca papulosa, Gloiopeltis spp., Gelidium spp., and Hizikia fusiformis which were high in biomass. It was noted that the farm of M. papulosa were liscenced only in Geomundo Islands in Korea.

Key words: marine flora and resources, Geomundo Islands, ecological study