태안군 황도교 건설에 따른 갯벌생태계 복원 영향평가

Evaluation of the Tidal-flat Ecosystem Restoration Effect on the Construction of Hwangdo Bridge in Taean

In 2011, a bridge was installed in Hwangdo, located in Taean-gun, Chungcheongnam-do, where seawater circulation was blocked for 30 years due to an inland dike. In this study, changes in the ecosystem of tidal-flats around the bridge were analyzed after the opening of the bridge(2011). To analyze the restoration effect, a survey of the marine environment around Hwangdo bridge was conducted and compared with the historical data before the restoration of Hwangdo bridge. After the construction of the bridge, the ecosystem of benthic community was changing due to the improvement of the tidal-flat environment around the bridge. The effect is manifested as a change of surface sediment grain-size in mudflat. The ratio of sand in the southern tidal-flats of Hwangdo bridge, which accounted for about 10 percent of the sand, has continued to increase since the sea-water circulation by the bridge. Due to the improvement of the tidal-flat environment, the number of species, habitat density, and biomass of the macrobenthos on the tidal-flat in Hwangdo is gradually increasing. The production of Manila clam(Ruditapes philippinarum) in the Hwangdo tidal-flat is also showing a steady increase. As the mudflat deposition environment, which had deteriorated due to the cutoff of sea-water circulation, has improved, more and more tourists are experiencing fishing activities such as manila clam digging. This shows that the effect of mudflat restoration due to seawater circulation continues. It is expected that the Hwangdo tidal-flat restoration project will be used as a success story in promoting similar tidal-flats restoration projects as sea-water circulation in the future.