바다목장해역의 해수 유동모델과 저차생태계 모델을 이용하여 저차생태계의 환경요인의 시공간적으로 변화를 파악하였다. 울진 주변해역에서 POM 모델을 이용하여 4대 분조(M₂, S₂, K₁, O₁)의 조석효과, 바람효과, 수온·염분의 효과, 해류를 고려하여 유동을 계산하였다. 대·소조기의 조류는 평해 남동쪽에서 가장 강한흐름이 나타났다. 잔차류의 크기는 표층, 중층 및, 저층에서 유사한 방향으로 유속 차이는 미약했다. 잔차류의 공간적인 분포를 보면 연안역을 따라 북동향류가 우세하고, 외양에서 흐름보다 연안에서 흐름이 우세하다. 이러한 유동 환경에서의 울진 바다목장 해역에서 저차생태계 모델을 이용하여 NH₄, NO₃, Chl-a, 동물플랑크톤 및 Detitus의 저차생태계의 시공간적인 변화를 파악하였다.

To understand the changes in physical parameters and phytoplankton size structure caused by tides, a fixed station in the Youngsan River estuary was monitored at 2-h intervals, on April 28, 2012 and August 12, 2012. No clear relationship was observed between the temperature and salinity changes and tidal levels in April. However, in August, temperature decreased during the ebb tide and increased during the flood tide, while salinity showed the opposite trend. In addition, there was no specific change in the phytoplankton biomass corresponding to tidal levels in April. In August, the total chlorophyll a and the biomass of net phytoplankton (>20μm ) increased almost 20 times during the ebb tide and decreased during the flood tide. The biomass of nanophytoplankton (<20μm ) showed a similar variation in response to tidal level changes. In April, the relationship between percent contributions of phytoplankton size structure and tidal levels was not clear. In August, the net phytoplankton was dominant in the early stage and nanophytoplankton was dominant in the later stage, while contribution of nanophytoplankton and net phytoplankton increased at high tide and low tide, respectively. Therefore, in April, other factors such as freshwater discharge were more important than the tide, whereas in August, when no freshwater discharge was recorded, the changes in semidiurnal tides influenced the physical parameters and phytoplankton dynamics. These results could contribute to the understanding of phytoplankton dynamics in the Youngsan River estuary.

The temporal variations of the suspended material concentration (SMC) during spring-neap tidal cycle was investigated at more than 30 stations in Deukryang Bay, Korea, in 1 and 23 July, 1992. The averaged total SMC in spring tide was two times more than those in neap tide. It can be explained that the strong tidal current in spring tide disturbed bottom waters and induced higher SMC in the bay. The areal distributions of SMC for the surface and the bottom layers in the bay shows much different patterns during spring and neap tidal cycle. We concluded that the vertical stratification intensity of water mass is important factor of the horizonatal distribution of SMC in the bay.