• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.339-343
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• 2011

This study is to examine the effect of freshwater influx on residence time to understand a long-term material transportation in enclosed bay. To predict the residence times of the coastal water in Masan bay, we were carried out the numerical simulations by using a EFDC model to simulate seawater circulation and particle tracking. The average residence times of Masan bay obtained from the particle release simulations under the condition to neglect a freshwater influx were estimated to be about 110 days in northern part of the bay to near Dotseom, 40 days in around Modo and 20 days in Budo to open sea. However, the average residence times under the condition consider with freshwater influx decreased about 81 days in both Region 1(northen Masan bay to near Dotseom) and Region II (Dotseom to Modo), but the Region III(Modo to Budo) and Region IV(Budo to open sea) incresed about 58 days and 17 days, respectively.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.127-132
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• 2004

본 연구는 2003 년 9월 내습한 태풍 매미로 인해 마산 진해 용원 지역을 포함하는 가덕수도 인근 해역의 태풍 매미의 풍역변화 특성과 개방형 및 폐쇄성 해역 등의 지형적 특성을 고려한 호안 월류 패턴을 고찰하고 이를 모식화하였다. 태풍 매미 통과시 진해만의 경우는 풍향이 E-ESE 인 시점이 파랑에너지가1 충분히 발달하여 입사할 조건에 해당되고 마산만의 경우는 풍향이 SE-S인 시점이며, 부산신항 인근 해역은 S-SSW의 풍향이 유세한 시점을 중심으로 태풍파랑을 산정하여야 구조물에 미치는 정확한 영향을 평가할 수 있을 것으로 판단된다. 따라서 이상 파랑의 내습에 따른 해양구조물의 안정정을 확보하기 위해서는 태풍 통과시 천해역의 풍역변화에 따른 수위변동 및 파랑장 영향을 해석하고 입사파랑에 의한 구조물의 피해를 최소화할 수 있는 방안의 연구 필요성을 강조할 수 있다.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.350-358
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• 2015

This study was designed to evaluate the sanitary characteristics of sea water in a part of the south coast, Korea and to check the seawater which is in compliance with the recommended bacteriological criteria for shellfish cultivation. The samples of sea water were collected at 14 sampling stations established in the survey area between March 2014 and October 2014. Food poisoning caused by seafood consumption is often associated with pathogenic microorganisms originated from fecal contamination. Therefore, fecal coliform is very important criteria for evaluating the safety of fisheries in coastal areas. The range of geometric mean (GM) and the estimated 90th percentile values of total coliform were 4.1~83.1 MPN/100 mL, and 11.7~834.1 MPN/100 mL, respectively. The GM and the estimated 90th percentile values of fecal coliform were 2.5~22.7 MPN/100 mL and 2.5~170.0 MPN/100 mL, respectively. Therefore, the bacteriological safety of seawater at this shellfish-growing area met with the Korean Shellfish Sanitation Program (KSSP) criteria for a growing area. However, the values are seasonally exceed the KSSP criteria, suggesting that the monitoring and evaluation of seawater quality is very important in shellfish-growing area.

• Ocean and Polar Research
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• v.25 no.2
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• pp.183-200
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• 2003

In order to assess the ecological changes induced by organic pollutants of the Shihwa Lake, BPI (Benthic Pollution Index) based on the benthic faunal community was employed. It was modified from Infaunal Trophic Index (ITI), and recommended as a pollution detecting method for the environmental assessment. The BPI values were calculated from the benthos data, which were collected for three terms: in 1980, before the Shihwa Lake was built up; in 1994-1997, which the Shihwa Lake was completely isolated from the outer seawater; in 1997-1999, after inflow of the outer seawater. Since the Shihwa Dike was constructed in February 1994, the pollution intensity of the lake had been increased from the narrow and inner part of the former Gyeonggi Bay and spread fast along the coast line of the Shihwa Lake. Then, in 1996 it showed the very high BPI levels all around the Lake. This serious polluted condition had been lasted till 1997, when the inflow of the seawater was begun. In 1998, from the nearest part of the Shihwa Gate, the BPI levels gradually became low in most area of the Lake, except its inner and narrow part. These greatly lowered BPI levels mean that the seawater inflow could be assumed to affect positively in the lake. Furthermore, BPI gave the same results from the other environmental assessment based on the abundance and the species richness of macrobenthic community. It shows that BPI could be useful as an effective method to assess the marine environment and evaluate the status of environmental conditions.

• Journal of Navigation and Port Research
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• v.26 no.2
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• pp.227-233
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• 2002

Recently, the water pollution of coastal sea area including harbor, bay and inland sea has been very serious and it causes u\\various environmental impacts. In this study, water flow system of Danghnag Bay, which has the narrow and long topographical characteristics with the narrow bay mouth and its flow is influenced principally by the tidal current, is investigated experimentally and numerically. In order to understand the tidal system of Danghang Bay, harmonic analysis is performed based on measured tidal range and flow velocity. In addition, numerical model for tidal exchange is developed considering conditions of Danghang Bay. Calculated results show good agreement with measurement. Lastly, based on the proposed numerical model, exchange ratio of seawater volume in Danghang Bay is predicted.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.469-470
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• 2001

경남 통영 안정만은 북동쪽으로 진해만과 연결되어 있고, 고성 당동만과 가조도 서쪽 어의도, 수도, 지도 둥의 섬으로 둘러 쌓인 반폐쇄성 내만으로서 굴, 피조개 등 패류양식이 주로 행해지고 있어 유기물 오염이 심각한 해역으로 해양수산부에 의해 특별관리어장으로 지정되어 현재 어장정화사업이 시행되고 있다. 본 조사는 이 해역의 해양생태계 조사를 통해 공단조성이 해양생태계에 미치는 영향을 파악하는데 그 목적이 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.255-257
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• 2001

진해 행암만은 반폐쇄성 내만으로서 생활하수 및 산업폐수의 유입에 의한 부영양화가 매우 심화된 해역으로서 겨울철에도 빈번하게 적조현상이 일어나는 해역이다. 그러나 매년 봄철부터 가을철까지는 부영양화 및 적조발생에 관한 조사는 많이 행하여 왔으나 진해만 및 마산만을 연구하기 위해 한 두 정점에 국한하여 조사가 이루어졌을 뿐이다. 특히, Park (1975)의 연구 이후 행암만에 대한 상세한 연구는 전무한 실정이며, 해수중 용존중금속 및 표층퇴적물중의 중금속농도분포도 거의 밝혀지지 않는 실정으로서 겨울철 행암만 수질과 표층퇴적물 중의 환경특성을 파악할 목적으로 본 조사를 수행하였다. (중략)

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.4
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• pp.279-287
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• 2010

To identify characteristics of the water quality at Goseong bay, we analyzed long term monitoring data collected at surface and bottom water which was accumulated during the period of 1987~2009. The result showed that the waters of Goseong bay represented mesotrophic level that is based on chlorophyll-a, DIP and DIN and seasonal average of COD that indicates level by the COD criteria. This analysis can be translated that the waters is comparatively clean even though the waters is in the closed bay that slowly diffuses influx mass. We also did the time series analysis, correlation analysis and regression analysis on the moving average of the water parameter at Goseong bay. According to the results, DIP showed a increasing trend as time passed while DIN was on a decreasing trend under the same condition. In the waters of Goseong bay, the phyto-plankton growth was shown to be limited by DIN concentration. The chlrophyll-a was at the peak in August, at $4.60{\mu}g/L$. As the seasonal average and index were the highest in November, it was understood that the balance of nutrient at Goseong bay was dependent more on inner factors, ie, mass farming of aquatic species and release of bottom sediment rather than on inflow of fresh water. Accordingly, it is needed to consider the balance of nutrient like DIP and DIN to manage the water quality or estuaries at Goseong bay.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.83-90
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• 2017

To understand the spatial-temporal distribution of seawater in Korea's South Sea, seawater movement and the distribution of water temperature has been analyzed using a hydrodynamic model (the Princeton Ocean Model). The directions of tidal currents were generally westward during flood tides and eastward during ebb tides. Northeastward Tsushima Warm Currents in the open sea, which is deeper than 50m were stronger than in coastal areas. Analysis of data from the hydrodynamic model showed that the water temperature in the semi-closed bay was relatively higher ($26{\sim}28^{\circ}C$) than in the open sea ($18{\sim}22^{\circ}C$). The exchange volume of semi-closed seawater was $10,331m^3/sec$ in Gwangyang Bay, $16,935m^3/sec$ in Yeosu-Gamag Bay and $13,454m^3/sec$ in Geoje-Hansan Bay. Therefore, it was shown that the lower seawater exchange volume is, the higher seawater temperature will be.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.165-166
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• 2000

가막만은 반폐쇄성 해역으로 해수의 유통이 잘 되지 않고 주변에 여수시의 생활하수가 유입되는 곳이다. 또한 양식어장 증가 및 화학공장의 건설 등 다양한 오염원의 증가로 만 북부에서는 하계에 빈산소 현상이 주년 나타나고 있어 수산피해가 우려된다. 본 연구의 목적은 표층퇴적물과 주상 퇴적물에 함유된 유기물과 금속성분을 분석하여 각 성분의 지화학적 특성을 이해하고 이들 물질의 오염원 분포 및 강도를 추정하는데 있다. (중략)