Impact of Sand Extraction on Fish Assemblages in Gyeonggi Bay, Korea

During 2006 and 2007, 35.0 x 10(6) m(3) of marine sand was extracted by the construction industry from Gyeonggi Bay, which is an area within the coastal waters off the Taean District of Korea. The goal of our study was to compare the catches and assemblage structure of fish in this sand mining area (SMA) with those of two other nonmining areas (NMAs) in the bay. An otter trawl was used to obtain fish samples in each area. Both cluster analysis and nonmetric multidimensional scaling of the species composition in the sampled areas showed a higher similarity between the two NMAs than between the NMAs and the SMA. Furthermore, the SMA had significantly lower species richness (R1), species diversity (H'), and fish abundance compared with the two NMAs. These results could be associated with bottom disturbance related to the mining of seabed sediments. In conclusion, we confirm that sand mining processes directly influence the Gyeonggi Bay sea floor ecosystem and have a continuous effect on the assemblage of fish in this ecosystem.