• Ocean and Polar Research
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• 제25권3호
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• pp.257-267
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• 2003

Deep-sea bottom photographs acquired in the Clarion-Clipperton fracture zone of the northeast equatorial Pacific were analyzed to reveal the controlling processes for the spatial variation of manganese nodule. The results show that regional-scale occurrence variations of manganese nodule are mainly controlled by primary productivity of surface water, sedimentation rate, and water depth (or carbonate compensation depth). As a result, the diagenetic accretion on nodules increases toward southwest while hydrogenetic accretion increases toward northeast. Considering the northwestward movement of Pacific Plate, this regional-scale variation of manganese nodule occurrence seems to be affected by oceanic environment during the active growth period (Oligocene-Miocene) of Pacific Plate.

• 수산해양기술연구
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• 제51권3호
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• pp.355-369
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• 2015

To examine species composition, abundance and biomass of fishes in the northwestern East Sea of Russian EEZ, trawl survey were conducted at 31 sampling stations from 2006 to 2008. Also, trawl survey were conducted at 21 sampling stations in the southwestern East Sea of Korean EEZ from 2006 to 2008. A total of 67 fishes were collected in the northwestern East Sea of Russian EEZ, a total of 39 fishes were collected in the southwestern East Sea of Korean EEZ. Among them, a total of 53 fishes were collected in the northwestern East Sea of Russian EEZ only, and a total of 25 fishes were collected in the southwestern East Sea of Korean EEZ only. Mean abundance per area which caught by trawl survey in the northwestern East Sea ranged from a high of $116,478inds./km^2$ in 2008 to a low of $19,737inds./km^2$ in 2006. And mean abundance per area in the southwestern East Sea ranged from a high of $89,129inds./km^2$ in 2006 to a low of $8,234inds./km^2$ in 2008. Mean biomass per area which caught by trawl survey in the northwestern East Sea ranged from a high of $11,333kg/km^2$ in 2008 to a low of $2,439kg/km^2$ in 2006. And mean biomass per area in the southwestern East Sea ranged from a high of $6,273kg/km^2$ in 2006 to a low of $1,062 kg/km^2$ in 2008. Cluster analysis, based on a Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into three different groups by depth in the northwestern and southwestern East Sea.

• 한국대기환경학회지
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• 제16권2호
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• pp.151-158
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• 2000

Since Pusan metropolitanarea where is composed complex terrain is connected to sea the sea-land breeze circulation and the mountain-valley circulation are apt to form A regional scale circulation system is formed at a region which has complex terrain because of curves of its and affect to the dispersion and advection of air pollutants. LCM Local Circulation Model which a propriety was verified described that sea breeze and valley wind at the daytime and land breeze and mountain wind at the nighttime were well devellped over the Pusan metropolital area. Next for the investigation of accuracy of simulated results an observed value at Kae-Kum and Su-Young on the pusan metropolitan area were compared with it at those points. From the comparison of the temperature and horizontal velocity between the results of LCM and an observed values they have a similar trend of a diurnal variation. For the prediction of dispersion and transportation of air pollutants the wind field should be calculated with high accuracy. A numerical simulation using LCM can provide more accuracy results around Pusan metropolitan area.

• Ocean and Polar Research
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• 제29권3호
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• pp.217-231
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• 2007

To explore limiting factors of spring bloom caused by waste disposal after dumping activity commenced in the Yellow Sea, we used a 1-dimensional temperature-ecological coupled model. The vertical structure of temperature and vertical diffusivity (Kh) are calculated by the temperature model with sea surface temperature using the 2.5 layers turbulence closure scheme. The ecological model applied results at the temperature model consisted of five state variables (DIN, DIP, phytoplankton, zooplankton, and detritus) forced by photosynthetically available radiation. We simulate year-to-year variations of plankton and nutrients using the coupled model from 1998 to 2000 and compare results of the model with observed data. It turned out that temperature is the growth factor of spring bloom in dumping area. During the winter the weak stratification made sufficient supply of the accumulated nutrients from the sea bed into the upper water column and led to the bloom in the coming spring. Radiation also turned out to be another important factor of spring bloom in the study area. Insufficient radiation of March 1999 showed low chlorophyll-a concentration despite sufficient nutrients in the surface.

• Journal of the korean society of oceanography
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• 제37권4호
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• pp.212-223
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• 2002

Cochlodinium polykrikoides bloom in 1995 was studied with a focus on an unusual coastal environment in the South Sea of Korea. Data on temperature, salinity, and zooplankton biomass during 1965-1998 and nutrients during 1990-1998 and chlorophyll-a during 1995-1998 were used in this study. These data were obtained from the serial oceanographic observations in Korean waters carried out by the National Fisheries Research and Development Institute. In 1995 the C. polykrikoides bloom began in the coastal area around Narodo Island in August and consequently occurred to the whole coastal area of the South and East Seas of Korea. During June-October 1995, the coastal environment was unusual compared with the long-term means during 1965-1998. In June 1995, sea surface temperature was 1-2$^{\circ}C$ warmer than in other years in all coastal areas, while salinity was high only to the east of Jeju Island. In August 1995, a strong coastal front appeared inshore of a line between Jeju and Tsushima Islands. In particular, a strong coastal front which showed the characteristics of upwelling front occurred in the coastal area around Narodo and Sorido Islands, not only because of a strong intrusion of the Tsushima Warm Current but also because of the upwelling of cold bottom water. Salinity was low in the neighboring waters of western side of Jeju Island. Nutrients and chlorophyll-a were high in the inshore area between Narodo and Sorido Islands in 1995 in contrast with the other years and areas. Zooplankton showed an unusually high abundance in the coastal area in October 1995. We conclude that the Tsushima Warm Current strongly influenced the South Sea of Korea in 1995 and created strong upwelling front bordering cold upwelled water in the coastal area around Narodo and Sorido Islands. It leads us that these physical structures introduce the favorable environment for the development of C. polykrikoides blooms. We suggest that C. polykrikoides has a bio-physical tolerance of high shear and stress and prefers frontal and upwelling relaxed areas as its habitat. We also find that nutrients were not supplied to the coastal area from the offshore where a low salinity water mass with high nutrients appeared around Jeju Island. Because the strong upwelling front protect the reach of offshore low saline water mass. The main source of nutrients was the upwelled water mass in the coastal area of Wando-Narodo-Sorido.

• 한국해양환경ㆍ에너지학회지
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• 제19권4호
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• pp.247-258
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• 2016

황해 태안반도 남서부 해역 8개 정점에서 해양퇴적물을 채취하여 퇴적물의 지음향 및 물리적 특성을 파악하였다. 전반적으로 사질 퇴적물이 우세하며 연구지역의 사질 퇴적물은 최대빙하기(LGM)이후 해수면 변동의 영향을 받아 연구지역에 퇴적되었다. 이후 금강 및 인근 연안에서 유입된 세립질퇴적물의 영향을 받은 지역은 니질 사 또는 사질 니가 발달했다. 이러한 퇴적 환경의 영향으로 정점별로 퇴적물 조직특성, 물리적 성질, 음파전달속도의 수평 수직적 차이가 나타난다. 음파전달속도, 평균입도 및 물리적 성질간의 상관관계를 보면 비교모델로 사용한 남해 퇴적물과 전반적으로 유사한 경향을 보이나 절대값에서 차이를 보인다. 이러한 차이는 퇴적환경, 광물조성 및 측정 시스템의 차이에 의한 것으로 사료된다.

• 해양환경안전학회지
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• 제27권5호
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• pp.584-593
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• 2021

해양의 퇴적물은 해저면을 구성하여 생물 서식지로 중요한 역할을 하고 있다. 그러나, 육상으로부터의 오염물 유입, 자가 오염 등의 내외부적 요인에 의한 오염은 점차 심각해지고 있어 생태학적으로 중요한 역할을 하는 퇴적물 관리에 대한 필요성이 더욱 증대되고 있다. 특히, 매립과 준설이 포함된 개발 사업에서의 퇴적물 영향에 대한 검토와 평가는 주변 생태계에 대한 사전적 보호와 관리의 측면에서 큰 의미를 지닌다. 본 연구에서는 공유수면개발 행위에 대한 해역이용협의서 중의 해양 퇴적물 평가의 지표가 되는 퇴적물 관리 기준에 대한 개선 방안을 제시하고자 하였다. 이를 위해 국내외의 해양퇴적물 평가 및 관리기준을 비교검토 하였다. 국내의 경우, 해양환경관리법에 적시된 관련 기준을 대상으로 하였다. 동시에 비교적 다양한 요소로 구성된 평가기준을 보유한 캐나다와 NOAA사례를 분석하였다. 또한 실제 평가기준 적용 및 운영 사례 분석을 위해 해역이용협의서 중 해저 퇴적물에 가장 큰 영향을 미칠 것으로 판단되는 최근 5년간(2016-2020)의 항만 및 어항개발 사업 사례를 분석하였다. 특히, 일반해역이용협의서 중 퇴적물의 평가 단계에서의 기준과 평가 요소 등을 분석하였다. 고찰과 분석을 통해 해역이용협의서 중 현재의 퇴적물 환경기준에 생태 위해성과 잠재적 인체 위해성에 대한 평가 요소를 고려할 필요가 있음을 제안하였다.

• 환경영향평가
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• 제20권2호
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• 한국대기환경학회지
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• 제19권1호
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• pp.1-11
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• 2003

Temporal and horizontal distributions of surface ozone concentrations covering the Busan metropolitan area were simulated by UAM -V (The Variable grid Urban Airshed Model) that was run with meteorological inputs taken from MM5 for ozone episode day (18 July 1999). UAM-V underestimated the daily maximum ozone con-centration about 14 ppb on average at all monitoring sites within Busan area comparing with observed value. but the correlation between observed and simulated values showed quite significant (R = 0.896, p< 0.01 on average). Higher concentrations of ozone occurred near the city center and industrial areas (western side of city) with high levels of anthropogenic source in the morning, and transport of ozone and its precursors by sea breeze developed in the afternoon contributed to elevated ozone levels in downwind rural areas. Particalarly in slightly downwind area of city center, the highest daily maximum ozone concentration ($\geq$120 ppb) was simulated by UAM-V at 1400 LST. Consequently, local environments including emission distributions and land -sea breeze circulation influenced ozone distributions in the Busan metropolitan area.

• 한국수산과학회지
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• 제41권6호
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• pp.505-510
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• 2008

To understand the oceanographic characteristics of Hupo coastal waters as regards the East Korean Warm Current and the North Korean Cold Current, current direction and velocity were investigated by deploying a current meter in Hupo coastal waters during the summer and fall of 2007. Wind data were obtained from the homepage of the Korea Meteorological Administration. Water temperature was measured using a temperature meter attached to the current meter and a mini log. During summer, a south wind prevailed, while during the fall the wind blew from the north. Cold surface waters occurred on a large scale in summer, while in the fall, warm bottom water occurred frequently. After mid-November, when the surface water was cooler than $15^{\circ}C$, there was no difference in water temperature between the surface and bottom layers.