인공용승구조물 설치해역에서 구조물 설치에 따른 해양환경변화를 조사하였다. 남해안의 전선역에 인접한 연구해역의 남동역에서 고온 고염의 분포가 하계에 뚜렷하게 나타났다. 또한 구조물 설치에 따른 유동의 변화 양상을 볼 수 있었다. 한편, 영양염 분포를 보면, 하계 영양염은 표층과 중층에서 구조물 투하 전인 2002년보다 구조물 투하 후인 2005년에 크게 증가하였다. 따라서 구조물 설치로 인한 구조물 설치 전과 후의 해양환경 변화양상은 구조물 설치 효과에 영향을 받고 있음을 알 수 있다. 인공용승구조물설치에 따른 해역의 해양환경특성을 파악하기 위해서는 구조물 설치 전 후의 단기적 비교로부터 보다 장기적인 해양환경조사를 통하여 구조물설치에 따른 효과가 제시되어야 한다.

In order to estimate volume transport by upwelling for single artificial seamount, same shape and size of artificial seamount already deployed was applied to numerical experiment. The result showed that strong upwelling appeared at front while took place downwelling at rear. The strongest upwelling existed at the top of the artificial seamount. Volume transport by upwelling was computed as 785 m3/s. Column arrangement was applied to two artificial seamount in three cases; case 1) no clearance, case 2) sixty-five meters of clearance as half of artificial seamount’s length, and case 3) hundred-thirty meters of clearance as an artificial seamount’s length. All cases of column arrangements showed more upwelling volume transport than that of single seamount. Particularly, the case of no clearance calculated as 106% and appeared the most upwelling effect comparing to two other cases. Row arrangement was also applied to two artificial seamount in three cases; case 4) no clearance, case 5) forty meters of clearance as an artificial seamount’s width, and case 6) eighty meters of clearance as twice of artificial seamount’s width. Upwelling volume transport in case 4 increased 48% than the case of single seamount. Other two cases of 5 and 6 were estimated as 97% increased and more effective than case 4. According to the case experiments, column arrangements show more upwelling volume transport than that of row arrangements. In cases of column arrangements, with decreasing clearance between two seamount, the effect increases while showing maximum value at clearance zero. In cases of row arrangements, on the contrary, with decreasing clearance between two seamount, the effect decreases while showing minimum value at clearance zero. Since simple barotropic condition was considered for this study, further study is necessary by considering baroclinic condition to get close to reality. In conclusion, in deploying artificial seamount, optimal arrangement should be well designed to enhance primary and secondary productivity and to increase the diversity of species as well as reducing time and space.

Recently, upwelling of anoxic bottom water mass have been frequently observed in northeast part of Tokyo Bay in Japan during summer to autumn. Since the colour of water surface becomes milky-blue or milky-green, the upwelling phenomenon is called `Blue Tide`. The data analysis of field surveys during `Blue Tide` appearance have been performed for understanding the physical features of the `Blue Tide` phenomena in Tokyo Bay. It becomes clear that (1) the formation of the anoxic bottom water correlates well with the temperature difference between the surface and bottom waters, (2) there are two necessary conditions for generating `Blue Tide` ; that is, strong stratification and off-shore wind. The strong southwest(on-shore) wind before the `Blue Tide` appearance may play an important role to make the stratification strengthen. When these conditions are larger and the northeast or east-northeast (off-shore) wind stronger than 5 m/s blows in succession, the `Blue Tide` upwelling appears at the head of Tokyo Bay.