• 한국패류학회지
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• 제28권3호
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• pp.259-267
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• 2012

Due to the oil spill incident in December 2007, every facility of oyster culture was removed in western coast especially in Taean and Seosan. To restore oyster resources in Taean and Seosan, we brought oyster seeds from southern area and monitored their growth. In addition we monitored the culture environment throughout the year, and observed the number of oyster larvae and attached spats on collectors during summer. The factors of water environment were appropriate for oyster culture in both study area. The growth of shell height was larger in Uihang-ri, Taean than Jungwang-ri, Seosan. Spawning was more intensive in a short time in Jungwang-ri, Seosan than Uihang-ri, Taean. The number of oyster larvae and spats of collectors were much more in Jungwang-ri, Seosan than Uihang-ri, Taean. This study showed that transplantation of healthy oyster seeds from southern area can be a way of restoration of oyster resources in western coast. In addition, systematic approaches are necessary by building a better understanding of regional characteristics to restore and enlarge the oyster culture farms in western coast. In summary Uihang-ri, Taean will be appropriate for cultivation farms and Jungwang-ri, Seosan for seedling grounds to increase oyster culture productivity.

• Ocean and Polar Research
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• 제30권2호
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• pp.181-191
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• 2008

This study aims at assessment of spatio-temporal distribution of demersal fish aggregations near the west coast of Jeju Island using hydroacoustic survey. A 200 kHz split beam transducer attached to a small towed body was used for all acoustic investigations. The received acoustic data were in situ acoustic target strength (TS, dB) for all pings and nautical area scattering coefficient(NASC, $m^2/mile^2$) for 0.1 mile along 12 acoustic transects. Demersal fish aggregations are distributed around the coastal slope having 20 to 30 m depth throughout all seasons. The concentration is higher during the summer season. With regard spatial distribution, higher demersal fish aggregations have been detected near the West coast of Shinchang and especially near Chagwi-do. Pelagic fish aggregations were higher to the south of Chagwi-do during the spring season. Additionally, standing stock of demersal fish aggregations from the NASC data, TS function, and length-weight function of dominant species was estimated as follows: 3.2 ton (CV 21.8%) in December 2006, 17.9 ton (CV 21.6%) in April 2007, 30.8 ton (CV 17.8%) in June 2007, and 22.5 ton (CV 24.2%) in October 2007. The application of hydroacoustic methods offers a new approach to understanding spatiotemporal structure and estimate the biomass of demersal fish aggregations in the coastal area. And the results can be made up limitations of qualitative analysis through net and diving for fisheries resources survey in coastal area.

• Fisheries and Aquatic Sciences
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• 제18권4호
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• pp.411-416
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• 2015

We estimated abundance of the finless porpoise Neophocaena asiaeorientalis in the west coast of Korea in 2011 and compared it to the abundance data estimated by Park et al. (2007). The two researches used same line transect method operated by a vessel, and the study area were divided into the offshore and the inshore regions to assess variations in their abundance. In offshore regions population density of finless porpoises was $0.122ind./km^2$, which was lower than $0.565ind./km^2$ estimated in 2004. In inshore regions the population density was $0.151ind./km^2$, which was much lower than $0.638ind./km^2$ estimated in 2005. Thus, we estimate that the population densities of the finless porpoises in both the offshore and the inshore regions of the west coast of Korea has decreased by approximately 70% between 2004/2005 and 2011.

• 수산해양교육연구
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• 제25권4호
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• pp.991-997
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• 2013

Distribution and occurrence of swimming crab, Portunus trituberculatus larvae were investigated in the mid-western coast of Korea in the Yellow Sea. P. trituberculatus larvae were collected in July and August from 2010 to 2012. Bongo net with 303 mesh was deployed once with a double oblique tow. Zoea I (ZI) densities were highest in all sampling months. Then densities of later larval stages decreased dramatically. In general, larval densities at the stations in northern parts and coastal areas were higher than those at the southern and offshore area. Because egg bearing seasons of P. trituberculatus in the study area are between April and August, larval densities, particularly, of ZI may be underestimated. Considering higher densities of ZI and lower ones of later stages, larvae may be transported to growing area and returned to the parental populations. Larval densities and sea surface temperature were not correlated.

• 대한원격탐사학회지
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• 제39권4호
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• pp.409-423
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• 2023

North Korea is carrying out reclamation activities in tidal flat areas distributed throughout the west coast. Previousremote sensing research on North Korean tidal flats either failsto reflect recent trends or focuses on identifying and analyzing tidal flats. Thisstudy aimsto quantify the impact of recent reclamation activitiesin North Korea's coastal areas and contribute knowledge useful for determining the best remote sensing methods for coastal areas with limited accessibility, such as those in North Korea. Using Landsat-8 OLI images from 2014-2022, we analyzed land cover changesin an area on the west coast of Pyeonganbuk-do where reclamation activities are underway. Unsupervised classification using the normalized difference water index and the random forest classification technique were each used to divide the study area into classification groups, and changes in their areas over time were analyzed. The resultsshow a clear decrease in the water area and a tendency to increase cultivated area,supporting the evidence that North Korea'sreclamation isfor agricultural land expansion.Along coasts behind seawalls, the water area decreased by nearly half, and the cultivated area increased by over 2,300%, indicating significant changes and highlighting the anthropogenic nature of the cover changes due to reclamation. Both methods demonstrated high accuracy, making them suitable for detecting cover changes caused by reclamation. It is expected that further quality research will be conducted through the use of high-resolution satellite images and by combining data from multiple satellites in the future.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 춘계학술발표회
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• pp.225-230
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• 2006

미래 지향적인 해양경찰 지방조직을 제안하기 위하여 먼저 미국, 일본, 영국의 Coast guard 지방조직을 비교 분석하였다. 통일에 대비하고 지역해역의 특성과 해양치안행정 환경에 부응하고 고품질 맞춤형 서비스 제공이 가능한 지방조직으로 서해, 남해, 동해 해역지방청을 기본으로 하는 해양경찰청의 지방조직을 제안하였다. 이러한 지방조직은 조직의 유연성과 정체성을 확보할 수 있을 뿐만 아니라 해양경찰의 발전 모델로 활용이 기대된다. 또 한 지방해양경찰청 조직의 실현과 발전을 위한 과제로 기능과 역할과제, 위민활동과제, 조직문화과제를 제시하였다.

• 수산해양교육연구
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• 제28권4호
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• pp.947-956
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• 2016

This study analysed the documents of Sea Area Utilization Consultation of JongChun and ApHae located in West Coast of Korea and NaJeong located in East Coast of Korea in order to find out problems of site surveys and numerical simulations for coastal erosion projects of ocean physics, and suggested the improvement way to go. Current especially like wave-induced current is the one of the important external forces to handle coastal erosion but underestimated in the west coast. In case of east coast the various tests including wave-induced current were conducted but less efficient to find out the reasons of coastal erosion. The stiffness structure to protect coastal line like beach made the secondary erosion by using them without sufficient analysis for the erosion. In order to consult a Sea Area Utilization Consultation those are needed to review the scenarios for external forces such as wave and tidal currents, the site surveys for external forces, the net sediment analysis for years, the long periods of monitoring, and the guide line and revision of the rule for coastal erosion.

• ALGAE
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• 제18권4호
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• pp.311-320
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• 2003

The community structure of benthic marine algae was investigated at Taean Thermal Power Plant and other places around Taean Peninsula, the west coast of Korea. Total of 100 species including 3 Cyanophyta, 14 Chlorophyta, 18 Phaeophyta, and 65 Rhodophyta were identified. The number of species was highest with 78 species at the Power Plant intake, followed by 61 at the discharge, 56 at Bunjeondo, and 50 at Maoe. It was noteworthy that a subtropical species Caulerpa okamurae was collected at the intake in autumn and it was the first observation in the west coast of Korea. The pattern of vertical algal distribution showed Gloiopeltis furcata occurred in the upper intertidal zone, Sargassum thunbergii and Corallina spp. in the middle and lower zone and Enteromorpha spp. in the lower middle zone. These were all dominant species except for Enteromopha spp., which was subdominant species. Other subdominant species were Chondrus ocellatus and Neorhodomela aculeata. The average diversity indices were between 0.70 and 1.20 at each area based on their dry weight. The similarity index was 0.79 between the algal flora of this study and that of 1987, indicating that the condition of the benthic environment remained unchanged since then. This area maintained its environmental quality, so the algal community remained same with similar structure. This study area seemed a suitable place for long term monitoring of the benthic environment where industrial facilities such as a power plant might affect the benthic algal community.

• Ocean and Polar Research
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• 제30권4호
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• pp.453-466
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• 2008

In order to examine the generation mechanism of long ocean waves along the west coast of Korea and to understand the amplification process of the long ocean waves, sea level, atmospheric pressure and wind data observed every minute from 2007 March 29 to 2007 April 1 were analyzed and onedimensional numerical ocean model experiments were performed. An atmospheric pressure jump propagated southeastward from Backryungdo to Yeonggwang along the west coast of Korea with speed of $13{\sim}27\;m/s$ between 2007 March 30 23:00 and 2007 April 1 1:30. Average magnitude of pressure jump was 4.2 hPa. As a moving atmospheric jump propagated from north to south along the coast, long ocean waves were generated and the sea level abnormally rose or fell at Anheung, Kunsan, Wido and Yeonggwang. Average amplitude of sea level rise (or fall) was about 113.6 cm. In a one-dimensional numerical ocean model, nonlinear shallow water equations were numerically integrated and a moving atmospheric pressure jump with traveling speed of 24 m/s was used as an external force. While the atmospheric pressure jump travels over 60 m depth ocean, a long ocean wave is generated. Because the propagation speed of the atmospheric jump is almost equal to that of the long ocean wave, Proudman resonance occurs and the long ocean wave amplifies. As the atmospheric pressure jump moves into the coastal area shallower than 60 m, the speed of the long ocean wave decreases and Proudman resonance effect decreases. However, the amplitude of the long ocean wave increases and wave length becomes shorter because of shoaling effect. When the long ocean wave hits the land boundary, amplitude of the long ocean wave drastically amplifies due to reflection. Data analysis and numerical experiments suggest that the southeastward propagation of an atmospheric pressure jump over the shallow ocean, which is a necessary condition for Proudaman resonance, generated the long ocean waves along the west coast of Korea on 2007 March 31 and the ocean waves amplified due to shoaling effect in the coastal area and reflection at the shore.

• 대한토목학회논문집
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• 제43권5호
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• pp.611-619
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• 2023

우리나라의 전국 해안가 대기중 염분량 1차 조사는 2003년에 3년 동안 실시되었으며, 그 결과인 해안가 비래염분 지역계수 및 염해환경 등급은 국내 구조물의 설계/시공/유지관리에 반영되어 활용되고 있다. 그러나 그 동안 기후 변화와 해안가 지형 변화 등에 의한 환경변화로 지역별, 해역별 해안가 대기중 염분량에도 변화가 예상되어 2021년부터 2차 조사를 실시중이다. 본 논문에서는 2차 조사의 1년 동안의 지역별, 해역별로 해안가 대기중 염분량의 계절적 변동에 대한 특징을 분석하였다. 또한 우리나라와 가까이 위치해 있고, 기후가 비슷한 일본의 해안가 비래염분량 조사 결과와 비교하여 분석 결과의 객관성을 높이고자 하였다. 2차 조사 결과 평균 비래염분량은 서해안이 가장 높았으며, 계절적 변동 또한 서해안이 가장 크게 나타났다. 해역별 계절적 변동을 보면, 동해안은 여름과 가을철에, 서해안은 가을과 겨울철에, 남해안은 여름에 비래염분량이 높게 나타났으며, 1차 조사에 비해 모든 해역에서 비래염분량이 월등히 높은 기간이 짧게 나타나 계절적 변동이 더 뚜렷하게 나타났다.