• 수산해양기술연구
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• 제51권4호
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• pp.567-575
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• 2015

Species composition in the coastal waters off Ulleungdo of Korea were examined based on catches bimonthly collected by trammel net in 2013. A total of 711 individuals and 181.9 Kg were caught and catches were composed of 4 classes 15 orders 27 families 52 species including 44 Pisces, 4 Gastropoda, 3 Cephalopoda, and 1 Echinodermata. The dominant species in biomass were File fish (Thamnaconus modestus), Atka mackerel (Pleurogrammus azonus), and Greenling (Hexagrammos otakii). Data were summarized using hierarchical cluster analysis (HCA) and detrended correspondence analysis (DCA) to examine similarity in species composition for each month, and community structure in Ulleungdo was divided into two groups. Community structures in February, April and December with low temperature and well-mixed surface water were distinguished from those in June, August and October with high temperature and strong stratification, which could be attributed to temporal changes in dominant species. Atka mackerel and Spear squid mainly caught in February and April, disappearing in June, August and October, and File fish outburst was shown in October. Because the water off Ulleungdo has been under low human pressure, it could be a good case study to elucidate effects of climate change on community structure and ecosystem in the East sea. Continuous surveys and further studies are required to demonstrate migration route and distribution of dominant species and long-term changes in community structure in the water of Ulleungdo.

• 한국수산과학회지
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• 제49권3호
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• pp.367-375
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• 2016

Marbled flounder Pseudopleuronectes yokohamae is a commercially important flatfish in the coastal waters of the East Sea off Pohang, Korea. Maturity and spawning dynamics of P. yokohamae were investigated based on samples collected by gill net and long line in the coastal waters off Pohang from January 2013 to December 2014. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. We found that the spawning period was December to February, wherein fecundity ranged from 55,760 eggs at 20.40 cm total length (TL) to 1,559,007 eggs at 46.6 cm TL. The relationship between TL and fecundity (F) was F = 0.0017 TL^3.5604 (R² = 0.6984), and F increased with increasing TL. We estimated the TL at 50% group maturity as 27.4 cm for female and 23.5 cm for male P. yokohamae, respectively. The results from this research will aid in the development of policies on season and minimum catch length for sustainable production of P. yokohamae. We propose that it is necessary to conduct long-term ecological monitoring for this species because biological properties such as spawning ecology and growth performance are being affected by climate change.

• 수산해양기술연구
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• 제46권4호
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• pp.406-415
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• 2010

The forming of fishing ground and the population ecological characteristics of yellowtail, Seriola quinqueradiata, in the coastal waters off Gim-nyeong of Jeju Island were investigated. The stock of yellowtail, Seriola quinqueradiata, between Jeju Island and coastal areas of the East Sea is probably the same. Water temperature probably is a major factor for controlling distribution of yellowtails in deeper, offshore areas off Jeju Island. However, the major factor that determines aggregation of yellowtails in coastal areas of Jeju Island, especially off Gim-nyeong is probably strong tidal currents driven by distribution of yellowtails rather than hydrological conditions such as Yellowtails collected off Jeju Island were from 1 to 4yrs old and about 50% of them were $1^{-yr}$ old, probably indicating overfishing. Jack mackerel was the major prey item for yellowtails off Gim-nyeong from October to March, suggesting concurrence of the two species.

• 한국지역지리학회지
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• 제14권2호
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• pp.114-125
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• 2008

본 연구는 GIS를 사용하여 메사추세츠 동부의 보스턴시에 위치한 넷폰셋 강 유역의 수질 오염 정도를 측정하기 위한 것이다. 관련된 오염물질로써 CDOM을 축출하여 지표면의 유수가 다양한 토지이용과 연계되어 바닷물로 흘러들어가는 과정을 예측하고 이를 모형화하게 된다. CDOM의 축출과 분석은 관련학과의 도움을 받아 그 결과를 산출하고, 이를 GIS의 공간분석 기법을 이용하여 지역과 지형적인 특성에 따라 오염물질이 전해지면서 토지이용에 어떠한 변화가 생기는지를 관측하게 된다. 수계의 형성과 강의 흐름, 그리고 토지이용 자료가 연구를 위해 분석 자료로 사용되었고, ArcGIS 9.2를 사용, 공간분석 기법을 통해 하위 분수계와 유동점, 토지이용 구획을 산출하게 된다. 이는 GIS 기법이 지형분석과 오염물질의 이동을 분석하는데 어떻게 활용될 수 있는지를 고찰하는 것으로써 의미있는 연구가 될 것이다.

• 한국해양학회지
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• 제6권1호
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• pp.25-36
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• 1971

대마난류 유역의 해양조사는 W st(1936), Tsujita(1957) 등이 보고한 바와 같이 1873년경 Schrenck, L.가 대마난류의 정체를 밝힌데서 시작된다. 한국 남해의 수리적 해황에 대해서는 Makaroff91915), Wada(1922), Nisida(1923, '24, '27, '28), Uda (1930, '31, '34a, '34b, '36, '50), Suda and Hidaka(1930a, '30b), Hidaka and Suzaki(1950), Miyazaki and Abe91960), Gong(1968), 그리고 Lee and Bong(1969)등, 여러사람에 의한 조사 보고가 있다. 한국 국립수산진흥원과 그 전신인 중앙수산 시험장은 제2차대전 후의 몇 년간의 공백을 제외하고는 매년 정기적으로 해양관측을 실시하여 어장환경요인을 해양조사년보와 해 어황속보를 통하여 어민에게 공표하여 왔다.(1935, '36ㅁ, '36ㅠ, '38, '42, '56, '64, '68, '70)

• 한국콘텐츠학회논문지
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• 제19권2호
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• pp.121-134
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• 2019

우리나라의 해양경찰권이 미치는 해역은 크게 내수, 영해, 접속수역, 배타적 경제수역, 대륙붕(이하 "국내해역"이라 한다) 및 공해로 구분하고 있으며, 이 중 국내해역에서의 해양경찰권은 국제법인 "해양법에 관한 국제연합 협약"을 수용한 국내법을 따른다. 그 밖에 공해에서는 이 협약을 따르도록 하고 있다. 한편, 국내해역을 벗어난 공해에서는 자국 선박이외 외국선박에 있어서는 해적행위 등 이 협약에서 금지하고 있는 반인류적 범죄행위에 한해 제한적으로 관할권을 허용하고 있다. 하지만 공해상에서 연안국의 해양안보와 선박의 안전을 위협하는 외국선박의 불법행위는 반인류적 범죄 이외 여러 유형의 범죄(case)가 발생할 수 있고 명확한 명문규정 없이 이에 행사된 연안국의 관할권은 국가 간 분쟁을 가져올 수 있는 개연성이 높다 할 것이다. 따라서 본 논문에서는 공해상에서 국제 해양질서를 유지하고, 연안국의 해양경찰권을 안정적으로 확보하기 위한 제도적 개선방안에 대해 제시하고자 한다.

• 한국연안방재학회지
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• 제4권1호
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• pp.7-19
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• 2017

In this study, waves and currents observed by acoustic AWAC, VECTOR and Aquadopp Profiler in Anmok coastal waters were analysed to account for the variability of wave and current and to understand the mechanism of sediment transport generated by wave-induced current in the surf-zone. The monthly variation of wave and residual currents were analysed and processed with long-term observed AWAC data at station W1, located at the water depth of about 18m measured during from February 2015 to September 2016. Wave-induced currents were also analysed with intensive field measurements such as wave, current, suspended sediment, and bathymetry data observed at the surf-zone during in winter and summer. The statistical result of wave data shows that high waves coming from NNE and NE in winter (DEC-FEB) are dominant due to strong winds from NE. But in the other season waves coming from NE and ENE are prevalent due to the seasonal winds from E and SE. The residual currents with southeastern direction parallel to the shoreline are dominant throughout a year except in winter showing in opposite direction. The speed of ebb-dominant southeastern residual currents decreasing from surface to the bottom is strong in summer and fall but weak in winter and spring. By analysing wave-induced current, we found that cross-shore current were generated by swell waves mainly in winter with incoming wave direction about $45^{\circ}$ normal to the shoreline. Depending on the direction of incoming waves, longshore currents in the surf-zone were separated to southeastern and northwestern flows in winter and summer respectively. The variation of observed currents near crescentic bars in the surf-zone shows different direction of longshore and cross-shore currents depending on incoming waves implying to the reason of beach erosion generating the beach cusp and sandbar migration during high waves at Anmok.

• 해양환경안전학회지
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• 제29권3호
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• pp.281-287
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• 2023

Establishing a ship's passage plan is an essential step before it starts to sail. The research related to the automatic generation of ship passage plans is attracting attention because of the development of maritime autonomous surface ships. In coastal water navigation, the land, islands, and navigation rules need to be considered. From the path planning algorithm's perspective, a ship's passage planning is a global path-planning problem. Because conventional global path-planning methods such as Dijkstra and A^* are time-consuming owing to the processes such as environmental modeling, it is difficult to modify a ship's passage plan during a voyage. Therefore, the D^* algorithm was used to address these problems. The starting point was near Busan New Port, and the destination was Ulsan Port. The navigable area was designated based on a combination of the ship trajectory data and grid in the target area. The initial path plan generated using the D^* algorithm was analyzed with 33 waypoints and a total distance of 113.946 km. The final path plan was simplified using the Douglas-Peucker algorithm. It was analyzed with a total distance of 110.156 km and 10 waypoints. This is approximately 3.05% less than the total distance of the initial passage plan of the ship. This study demonstrated the feasibility of automatically generating a path plan in coastal navigation for maritime autonomous surface ships using the D^* algorithm. Using the shortest distance-based path planning algorithm, the ship's fuel consumption and sailing time can be minimized.

• Ocean and Polar Research
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• 제32권3호
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• pp.269-289
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• 2010

In Summer 2008, a multidisciplinary survey was conducted onboard R/V Haeyang 2000 to understand plankton response to the three distinct physico-chemical settings that developed in the Ulleung Basin of the East Sea. Baseline settings of hydrographic conditions included the presence of the thin (<20 m) Tsushima Surface Water (TSW) on top of the Tsushima Middle Water (TMW). It extends from the Korea Strait to $37^{\circ}N$ along the $130^{\circ}E$ and then turns offshore and encompasses the relatively saline (T>$26^{\circ}C$, S>33.7) Ulleung Warm Eddy surface water centered at $36.5^{\circ}N$ and $131^{\circ}E$. A relatively colder and saline water mass appeared off the southeastern coast of Korea. It was accompanied by higher nutrient and chlorophyll-a concentrations, suggesting a coastal upwelling. Most of the offshore surface waters support low phytoplankton biomass (0.3 mg chl-a $m^{-3}$). A much denser phytoplankton biomass (1-2.3 mg $m^{-3}$) accumulated at the subsurface layer between 20-50 m depth. The subsurface chlorophyll-a maximum (SCM) layer was closely related to the nutricline, suggesting an active growth of phytoplankton at depth. The SCM developed at shallow depth (20-30 m) near the coast and deepened offshore (50-60 m). A fucoxanthin/zeaxanthin ratio was high in coastal waters while it was low in offshore waters, which indicated that diatoms dominate coastal waters while cyanobacteria dominate offshore waters. The community structure and biomass of phytoplanktonare closely related to nitrogen availability. Zooplankton biomass was higher in the coastal region than in the offshore region while species richness showed an opposite trend. Zooplankton community structure retained a coastal/offshore contrast. These suggest that summer hydrography is a stable structure, lasting long enough to allow a hydrography-specific plankton community to evolve.

• 한국수산과학회지
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• 제17권3호
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• pp.219-229
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• 1984

1983년 7월 $25{\sim}31$일의 대한해협에서 실시한 관측자료를 사용하여 대한해협 서수도 수계의 화학적 성분을 분석 조사하였다. 그 결과 낙동강 유출수, 쓰시마 난류수, 거제도 연안수 및 울산 연안수의 4개의 수계로 구분되었다. 한편 낙동강 유출수의 영향은 거제도쪽 보다 부산영도인 동해 남부 연안쪽이 더 컸다. 이들 수계의 특성으로 먼저 낙동강 유출수는 투명도 3m 이하, 수색 7인 황토색 물로 표면의 수온, 염분, 용존산소, 인산염은 각각 $18{\sim}19^{\circ}C,\;31\%0$ 이하, $4.5{\sim}50ml/l,\;0.25{\sim}0.5{\mu}g-atom/l$이었고 또 질산염과 규산염은 해역중 가장 높은 간인 $10.0{\mu}g-atom/l$ 이상이었다. 쓰시만 난류수는 투명도 15m 이상, 수색 $4{\sim}2$의 맑은 물로 표면수온 $23^{\circ}C$내외 염분$32{\sim}33\%0$의 고온 저염수이다. 또한 표면의 용존산소는 5.0ml/l이상, 인산염, 질산염, 규산염은 각각 0.25, 2.0, $2.5{\mu}g-atom/l$ 이하로 해역중 가장 낮은 값이었다. 거제도 연안수는 표면수온 $20{\sim}21^{\circ}C$, 염분 $33\%0$이상의 비교적 저온 고염이고 표면 용존산소량이 5.0ml/l 이하, 인산염 $0.5{\mu}g-atom/l$ 내외 질산염과 규산염은 각각 $3.5{\mu}g-atom/l$ 이하로 나타났다. 또한 울산 연안수는 관측 해역중 가장 표면수온이 낮은 $16^{\circ}C$ 이하, $33.5\%0$ 이상의 저온고염이고, 용존산소, 인산염, 질산염, 규산염은 상당히 높은 값을 가져 저층수의 연안용승으로 인한 것이 아닌가 생각된다.