• 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.

• 대한조선학회논문집
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• 제55권1호
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• pp.83-91
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• 2018

In this paper, usefulness of marine radar for water waves measurement in coastal waters is presented. We installed a marine radar to acquire radar images of water wave around light beacon at Jujeon in Ulsan. Also, a series of analysis procedures for obtaining the wave information from the acquired image is described with a schematic diagram. We compared analysis results of radar images with measurement values using wave height gauge at light beacon. In order to improve accuracy of analysis results, detailed water depth information is essential. In conclusion, in case of the use of radar for water waves measurement, it is shown that it is very necessary to increase the accuracy of measurement by consideration of the water depth in the dispersion relation of water waves.

• Ocean and Polar Research
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• 제33권1호
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• pp.13-20
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• 2011

Comprehensive data collection was carried out between 2001-2006 to investigate the concentration levels of chlorophyll-a, nutrients (DIN and DIP), and COD for surface waters of Korean coastal areas. A statistical analysis of these parameters was carried out on the basis of the frequency distribution of their concentration. Furthermore, the numeric grading for chlorophyll-a, DIN, DIP, and COD concentrations were derived statistically from the normalized frequency distribution of log-transformed data. The statistical grading clearly reflects the water quality characteristics of three Korean coastal water bodies (Western, Southern and Eastern coastal zones), which indicate common environmental and ecological characteristics. So, this study could provide useful information to set up the guideline for water quality assessment of Korean coasts.

• 수산해양기술연구
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• 제58권1호
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• pp.59-67
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• 2022

This study assessed the levels of water qualities and microbials contamination of inland olive flounder farms in Jeju in the summers from 2015 to 2017. Three farms (A-C) located in a concentrated area using mixing coastal seawater and underground seawater and one farm (D) located in an independent area using only coastal seawater were selected. Total ammonia nitrogen (TAN) reached a maximum of 0.898 ± 1.024 mg/L as N in the coastal seawater of A-C, which was close to the limit of the water quality management goal of the fish farm. TAN in the influent from A-C was up to three times higher than that of D, so that the discharged water did not spread to a wide range area along the coast and continued to affect the influent. TAN of the effluent in A-C increased by 2.7-4.6 times compared to the influent, resulting in serious self-pollution in the flounder farm. Heterotrophic marine bacteria in the influent of A-C was about 600 times higher than D, and the discharge of A-C was increased by about 30 times compared to the influent.

• 한국수자원학회논문집
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• 제37권11호
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• pp.939-947
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• 2004

해안을 통하여 유출되는 지하수량은 하천 유출량에 비하여 상대적으로 크기는 작으나 해안 지역의 지하수자원의 개발과 연안의 오염과 관련하여 중요성을 가진다. 선행 연구에서는 관측정 수위, 투수계수 등의 간단한 자료만을 가지고 지하수의 해안 유출량을 평가하는 방법을 제시하였다 본 연구에서는 남해안과 서해안과 같이 해안선의 형태가 복잡한 경우에 평균동수경사, 해안선의 폭과 담수층의 평균 두께를 산정하는 방법을 제시하여 지하수 해안유출량 평가의 정확도를 높이는 방법을 제안하였다. 제안된 평가 방법은 경계면모델을 이용한 수치해와 비교하여 평가되었다. 해안선의 복잡성을 고려하지 않은 Darcy의 법칙의 적용에 비하여 정확도가 대폭 개선되었다.

• 해양환경안전학회지
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• 제23권5호
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• pp.524-531
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• 2017

본 연구는 생태계 모델을 이용하여 부산연안으로 유입되는 부하량 삭감에 따른 해역의 수질개선 정도를 예측하였다. 모델링 결과에 의하면 COD, T-N, T-P 모두 수영만 연안과 낙동강 하구에서 뚜렷한 개선을 나타냈으며, 수영만을 제외한 만 중부에서 만 동쪽까지는 수질개선이 거의 나타나지 않았다. 이는, 부산연안이 남해에 위치한 다른 해역에 비해 개방형경계를 가지고 있어서, 물질교환이 빠르기 때문으로 판단된다. 수질개선을 위한 본 해역의 삭감 COD 부하량은 타 해역에 비해 적었고, 총 유입부하량에 대한 삭감비율 또한 작게 나타났다. 본 연구에 적용한 부하삭감량을 적용하면 수영만, 낙동강 하구부근에서 뚜렷한 수질개선효과를 얻을 수 있을 것으로 판단된다.

• 한국해안해양공학회지
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• 제19권2호
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• pp.179-182
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• 2007

본 연구에서는 연안침식방지와 친수공간을 제공하기 위한 목적으로 새로 개발된 환경친화형 친수호안블록의 성능을 검증하기 위하여 반사율과 안정성을 대상으로 수리모형실험을 실시하였다. 실험 결과 블록의 현장적용 가능성이 있음을 확인하였다.

• ALGAE
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• 제19권3호
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• pp.247-255
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• 2004

This study was to clarify the variations in a marine ecosystem through examining the species composition of phytoplankton in the coastal water of Baegyado Island during winter. Water temperature, salinity, SS, NH$_4$-N, NO$_2$-N, NO$_3$-N and SiO$_2$-Si were significantly different and in inverse proportion to the chlorophyll a and species number according to stations and water depth. The total number of species was 88, composed of 94% Bacillariophyceae, 3.4% Chrysophyceae, 2.2% Dinophyceae and 1.1% Euglenophyceae. The dominant species were Rhizosolenia setigera, Skeletonema costatum and Stephanopyxis palmeriana. The maximum of standing crops was $5,450cells{\cdot}ml^(-1)$, while the minimum was $1,700cells{\cdot}ml^(-1)$. The coastal water was influenced with two water bodies which had characteristics of low water temperature - low salinity and high water temperature - high salinity.

• 환경영향평가
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• 제16권2호
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• pp.177-186
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• 2007

The composition of water-friendly space in the port and harbour developments provides the accessibility to the sea and thus resting & recreational function of the local citizen, which should be treated importantly for the eco-friendly coastal development. However, the high demand on water-friendly space can induce another environmental problem because most port and harbour developments require marine reclamation and the water-friendly space are made up on the reclamation area. The present study analysed the problems and suggested matters to be considered in composing the water-friendly space of port and harbour developments. The study also established the management direction by site characteristics of port and harbour. In addition, we attempt to find a plan to avoid the water-friendly space composition with environmental damage and to secure the environmental and public soundness in site selection, land use and facilities plan based on case studies.

• 환경생물
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• 제30권4호
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• pp.328-338
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• 2012

남해 서부 연안역의 식물플랑크톤 군집 및 환경요인의 계절별 변화를 관찰하고자 2009년 4월부터 2010년 2월까지 계절별 조사를 수행하였다. 환경요인의 변화는 multidimensional scaling (MDS)에 따라 수괴의 변화를 분석하였을 때, 남해 연안역 수괴 (SW; South-western coastal Water mass) 및 남쪽에서 유입되는 고염의 외양 수괴(TW; Tsushima current Water mass), 서쪽 제주해협을 통해 유입되는 저염의 서해 연안수괴 (YW; Yellow sea Water mass), 그리고 해안의 하천으로부터 계절적으로 유입되는 담수(CW; Closed bay Water mass)가 영향을 미치고 있었다. 이들 수괴는 해양 환경의 시 (계절) 공간적 특성에 따라 발달과 확장 및 축소되고 있었다. 즉, 연안에서 외해역 또는 외해역에서 연안 방향(남-북 방향) 그리고 서쪽(진도 주변 해역)에서 동쪽 방향 (동서 방향)의 농도 경사를 보인다. 이러한 남-북 방향의 공간 변동은 연안에서 하천과 지하수로 유입되는 연안 담수(낮은 염분과 높은 영양염 농도)와 대마 해류(고염분과 저영양염) 사이의 혼합에 의한 것이며, 동-서방향의 공간 변동은 제주해협을 통해 남해 연안으로 유입되는 서해의 연안수(저염분과 고영양염)와 대마 해류 사이의 혼합에 의해 조절되고 있는 것으로 해석된다. 식물플랑크톤은 고영양염을 보인 서해 연안수 및 여자만, 득량만에서 높은 개체수를 보였다. 식물플랑크톤 군집별 특성은 규조류가 90% 이상 높은 비율을 차지하였으나 대마 해류 수괴에서 와편모조류가 상대적으로 높아 수괴 특성에 따른 분류군의 차이를 보여 수괴가 갖는 기원적 특성 (original characteristics)의 차이를 보였다.