Community Structure and Health Assessment of Macrobenthic Assemblages at Spring and Summer in Geoje-Hansan Bay, Southern Coast of Korea

This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Geoje-Hansan Bay, Southern Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May (spring) and August (summer) 2013. The total species number and mean density were 300 species and , respectively. The major dominant species were the polychaetes Lumbrineris longifolia (), Aphelochaeta monilaris (), the bivalve Musculista senhousia () and the polychaete Praxillella affinis (). From the community statistics [cluster analysis and nonmetric multidimentional scaling (NMDS) ordination], the macrobenthic community was distinguished into two groups of inner bay (farming ground of near Sandal Island) and channel station(from Hansan Island to Chubong Island) group. In this study, the ecological status was assessed by four biotic indices Shannon`s H`, the ATZI Marine Biotic Index (AMBI), multivariate-AMBI (M-AMBI) and the Environment Conservation Index (ECI). The ecological status of the macrobenthic community in Geoje-Hansan Bay were poorer in the inner bay station than in the channel station. The results of the present study showed that three biotic indices (Shannon`s H`, M-AMBI and ECI) were valid as an index for evaluating the ecological status than the AMBI.