• Title/Summary/Keyword: Near sea

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A Newly Recorded Sea Star of Genus Henricia (Asteroidea: Spinulosida: Echinasteridae) from Jeju Island, Korea

  • Shin, Sook;Ubagan, Michael D.
    • Korean Journal of Environmental Biology
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    • v.33 no.4
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    • pp.390-393
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    • 2015
  • Some asteroid specimens were collected at a depth of 150 m near Moseulpo in Jeju Island, Korea using fishing nets on October 2014. The specimens were identified as Henricia pacifica Hayashi, 1940 belonging to the family Echinasteridae of order Spinulosida. In the Korean fauna, seven species of genus Henricia were reported of which two species, H. nipponica and H. ohshimai, were distributed in Jeju Island. The morphological characteristics of this species were re-described with illustrations.

Distribution and Strandings of Endangered Sea Turtles in Korean Waters (한국 연안의 멸종위기 바다거북의 분포 및 좌초 현황)

  • Moon, Dae-Yeon;Jung, Min-Min;An, Yong-Rock;Choi, Seok-Gwan;Oh, Bong-Se;Kim, Zang-Geun;Lee, Chu;Kim, Moon-Jin;Kim, Sam-Yeon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.42 no.6
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    • pp.657-663
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    • 2009
  • This paper reports the strandings of sea turtles on Korean shores monitored for the first time in 2008. A total of 19 sea turtles, consisting of 12 greens and 7 loggerheads, were recorded as stranded from the east coast to the south including Jeju Island. Reported strandings reached a peak in July and dominant area was Jeju Island. The curved carapace length of loggerhead sea turtles ranged 65-84.2cm and that of green sea turtles ranged 39.2-90cm, indicating most of them were immature to sub-adult. Out of 19 turtles, 11 were found dead with unknown reasons. Possible causes of death may include drawning by fishing gear, swallowing of marine debris, boat collision, and diseases. An immature green sea turtle tagged with a satellite transmitter spent winter near Jeju Island where it was released, suggesting that the Island provide immature greens a feeding ground. Considering thousands of sea turtles crawl on Japanese shores for nesting every year, the number of sea turtles reported in Korean waters was relatively small. Therefore, it is suggested that an appropriate monitoring system be necessary to protect and conserve endangered sea turtle species in Korean waters.

Study on the Acoustic Behaviour Pattern of Fish Shool and Species Identification 1. Shoal Behaviour pattern of anchovy (Engraulis japonicus) in Korean waters and Species Identification Test. (어군의 음향학적 형태 및 분포특성과 어종식별에 관한 연구 1.한국 연근해 멸치어군의 형태 및 분포특성과 종식별 실험)

  • 김장근
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.1
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    • pp.52-61
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    • 1998
  • We studied behaviour pattern of anchovy (Engraulis japonicus) shoal by a method of shoal echo integration and tested species identification by a method of artificial neural network using the acoustic data collected in the East China Sea in March 1994 and in the southern coastal waters of the East Sea of Korea in March 1995. Between areas, frequency distribution of 10 shoal descriptors was different, which showed characteristics of shoal behaviour in size, bathymetric position and acoustic strength. The range and mean of shoal size distribution in length and height was wider and bigger in the southern coastal waters of the East Sea than in the East China Sea. Relative shoal size of China Sea. Fractal dimension of shoal was almost same in both areas. Mean volume reverbration index of shoal was 3 dB higher in the southern coastal waters of the East Sea than in the East China Sea. The depth layer of shoal distribution was related to bottom depth in the southern coastal waters of the East Sea, while it was between near surface and central layer in the East China Sea. Principal component analysis of shoal descriptors showed the correlation between shoal size and acoustic strength which was higher in the southern coastal waters of the East Sea, than in the East China Sea. Correlation was also found among the bathymetric positions of shoal to some degree higher in the southern coastal waters of the East Sea than in the East China Sea. The anchovy shoal of two areas was identified by artificial neural network. The contribution factor index (Cio) of the shoal descriptors between two areas were almost identical feature. The shoal volume reverberation index (Rv) was showed the highest contribution to the species identification, while shoal length and shoal height showed relatively high negative contribution to the species identification.

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Species Composition and Spatial Distribution of Euphausiids of the Yellow Sea and Relationships with Environmental Factors

  • Yoon, Won-Duk;Yang, Joon-Yong;Lim, Dong-Hyun;Cho, Sung-Hwan;Park, Gyung-Soo
    • Ocean Science Journal
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    • v.41 no.1
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    • pp.11-29
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    • 2006
  • We investigated species composition and spatial distribution of the euphausiid community in the Yellow Sea and identified the relationship with environmental factors (temperature, salinity, chlorophyll $\alpha$, nitrate, phosphate, and silicate) using bimonthly data from June, 1997 to April, 1998. The environment varied during the sampling period. In warm seasons, thermocline was well developed rendering lower temperature and higher salinity and nutrient concentrations in the bottom layer. During cold seasons the water column was well mixed and no such vertical stratification was noted. Horizontal distribution of temperature, however, differed slightly between near-coast and offshore areas because of the shallow depth of the Yellow Sea, and between southern and northern areas because of the intrusion of water masses such as Yellow Sea Warm Current and Changjiang River Diluted Water. Four euphausiid species were identified: Euphausia pacifica, E. sanzoi, Pseudeuphausia sp. and Stylocheron affine. E. sanzoi and S. affine were collected, just one juvenile each, from the southern area in June and December, respectively. Pseudeuphausia sp. were collected in the eastern area all the year round except June. E. pacifica occurred at the whole study area and were the predominant species, representing at least 97.6% of the euphausiid abundance. Further, the distribution pattern of the species was varied in regards to developmental stages (adult, furcilia, calyptopis, egg). From spring to fall, E. pacifica adults were abundant in the central area where the Yellow Sea Bottom Cold Water prevailed. Furcilia and calyptopis extended their distribution into nearly all the study area during the same period. From late fall to winter, adults were found at the near-coastal are a with similar pattern for furcilia and calyptopis. The distribution pattern of E. pacifica was consistent regarding temperature, salinity, and three nutrients during the sampling period, whereas chlorophyll $\alpha$ showed a different pattern according to the developmental stages. The nutrients should indirectly affect via chlorophyll $\alpha$ and phytoplankton concentration. With respect to these results, we presented a scenario about how the environmental factors along with the water current affect the distribution of E. pacifica in the Yellow Sea.

Utilization of the Information of Fishing and Sea Condition for Common Squid (Todarodes pacificus) Using Angling in the East Sea: Relationships between Fishing Ground and Sea Temperature (동해 오징어(Todarodes pacificus) 채낚기어업의 어·해황정보의 유효이용 -어장형성과 수온과의 관계-)

  • Jeong, Dong-Gun;Rho, Hong-Kil
    • Journal of Fisheries and Marine Sciences Education
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    • v.10 no.1
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    • pp.31-52
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    • 1998
  • In this paper, we analyzed the relationships between the fishing ground formation and the sea condition information, surface, mid and bottom layer temperature that is necessary for fishing point selection of angling to catch squid in the East Sea. There was a little differences between temperature measured by every fishing boat on fishing operating and prompt reports of fishing and sea condition about fishing ground formation of angling. And then the result examined by using SST that is a important information of sea condition for the fishing position selection follows as ; We knew, even if the differencs of sea condition each year, SST with a lot of fishing boats was generally within the extnet of $2^{\circ}C$. But the result examined by the limit time about the temperature of mid and bottom layer for the groups of fishing boats not to measure and for the near sea measurement to be done only within EEZ waters follows as ; About the temperature of 50m layer on early in June and July in operating waters of the group of fishing boats, the fishing ground was formed from $10^{\circ}C$ to $12^{\circ}C$ between warm waters and cold waters, afterwards we can seize that the fishing ground was moving to waters from $5^{\circ}C$ to $8^{\circ}C$ at near of polar front. In the coastal waters, we knew that fishing ground is formed to waters from $10^{\circ}C$ to $12^{\circ}C$ at the southern of polar front about the temperature of 50m layer.

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An Analysis on the Climate Change Exposure of Fisheries and Fish Species in the Southern Sea under the RCP Scenarios: Focused on Sea Temperature Variation (RCP 시나리오에 따른 남해안 어업 및 어종의 기후변화 노출 분석 : 수온 변동을 대상으로)

  • Kim, Bong-Tae;Lee, Joon-Soo;Suh, Young-Sang
    • The Journal of Fisheries Business Administration
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    • v.47 no.4
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    • pp.31-44
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    • 2016
  • The purpose of this study is to analyze the climate change exposure of fisheries and fish species in the southern sea of Korea under the RCP climate change scenarios. The extent of exposure was calculated through weighted sum of the sea temperature forecasted by National Institute of Fisheries Science, and the weight were obtained from the time-space distribution of each fisheries or species, based on the micro-data for the fishing information reported by each fisherman. Results show that all the exposed sea temperature of RCP8.5 is higher than that of RCP4.5 in year 2100 as well as in near 2030, therefore it is thought to be very important to reduce the GHG emission even in the short term. The extent of exposure was analyzed to be comparatively high especially in the fisheries such as anchovy drag nets and species like cod, anchovy and squid. Meanwhile the method of this study is considered to be excellent to obtain the accurate extent of exposure under RCP scenarios, and therefore it is applicable on assessing the vulnerability of climate change in fisheries.

A study on Sea-salt distribution of High-rise Apartments in Waterfront Area (워터프런트 지역 고층아파트의 해염분포에 관한 연구)

  • Doe, Geun-Young;Lee, Han-Seok;Song, Hwa-Cheol
    • KIEAE Journal
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    • v.6 no.1
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    • pp.33-38
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    • 2006
  • The purpose of this study is to investigate the concentration of sea-salt distribution giving great characteristic environmentally. Therefore the field measurement was conducted to target high-rise apartments constructing in reclaimed land of Busan and measured the concentration of sea-salt by means of distance and height of high-rise apartments from coast. The results of this study were as follows ; 1) The more a horizontal distance is far from coast, the more concentration sea-salt become low. But this study can not draw conclusion exactly as differ from a tendency of the thing close to the coast and the land. 2) In the near seaside, No.132 apartment accords existing research result that in difference of the concentration of sea-salt by height, the more height is high, the more that is high. But in seaside, No.117 apartment of middle point appears that the upper story and the lower story than middle story. Once more, in inland, No.132 apartment and No.117 apartment tend toward opposite it of the seaside. The reason that the result of this measurement and existing study is not agreement is thought that it occurs to turbulent flow between apartments by construction of high-rise apartments group.

Atmospheric Analysis on the Meteo-tsunami Case Occurred on 31 March 2007 at the Yellow Sea of South Korea (2007년 3월 31일 서해에서 발생한 기상해일에 대한 기상학적 분석)

  • Kim, Hyunsu;Kim, Yoo-Keun;Woo, Seung-Buhm;Kim, Myung-Seok
    • Journal of Environmental Science International
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    • v.23 no.12
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    • pp.1999-2014
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    • 2014
  • A meteo-tsunami occurred along the coastline of South Korea on 31 March 2007, with an estimated maximum amplitude of 240 cm in Yeonggwang (YG). In this study, we investigated the synoptic weather systems around the Yellow sea including the Bohai Bay and Shandong Peninsula using a weather research and forecast model and weather charts of the surface pressure level, upper pressure level and auxiliary analysis. We found that 4-lows passed through the Yellow sea from the Shandung Peninsula to Korea during 5 days. Moreover, the passage of the cold front and the locally heavy rain with a sudden pressure change may make the resonance response in the near-shore and ocean with a regular time-lag. The sea-level pressure disturbance and absolute vorticity in 500 hPa projected over the Yellow sea was propagated with a similar velocity to the coastline of South Korea at the time that meteo-tsunami occurred.

Muscle Quality of Cultured and Wild Red sea bream (Pagrosomus auratus) (양식 및 자연산 도미(Pagrosomus auratus) 어육의 품질 특성에 관한 연구)

  • Lee, Kyung Hee;Lee, Young Soon
    • Korean journal of food and cookery science
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    • v.15 no.6
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    • pp.639-644
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    • 1999
  • The objective of this study was to compare the quality characteristics of cultured and red sea bream. The color of dorsal muscle was different between wild and cultured red sea bream. Lipid content of the dorsal muscle was higher in cultured fish than in wild one. The contents of moisture and crude protein in cultured fish muscle were almost same as those of wild one. Sensory evaluation of raw fish meat showed that cultured fish had lower preference in appearance, taste and texture than wild one. Especially the texture of cultured raw fish meat had lower preference than wild meat. For cooked fish meat, cultured fish were harder and less juicy than wild fish. These textural differences between wild and cultured meats were confirmed by objective evaluation including the measurements of hardness, springiness, and cohesiveness. Light microscopic observation showed that cultured red sea bream had more lipid in the surface layer near epidermis than wild one. Also more lipid droplet between muscle fibers were observed in cultured red sea bream by SEM.

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Surface Heat Flux and Oceanic Heat Advection in Sendai Bay

  • Yang Chan-Su;Hanawa Kimio
    • Korean Journal of Remote Sensing
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    • v.22 no.1
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    • pp.11-24
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    • 2006
  • Coastal sea surface temperature (CSST) and meteorological data from January through December 1995 are used to estimate the net surface heat flux and heat content for Sendai Bay. The average annual surface heat flux in the area north of the bay is estimated to be $+35Wm^{-2}$, whereas the southwestern area is estimated to be $+56Wm^{-2}$. Therefore, the net surface heat flux shows a net gain of heat over the whole bay. The largest heat gain occurs near Matsukawaura, where the strong Kuroshio/Oyashio interaction produces anomalously cold SST and wind is more moderate than in other regions of Sendai Bay over most of the year. The lowest heat gain occurs around Tashiro Island, where the temperature difference between air and sea surface is lower and wind is stronger. The heat budget shows that both surface forcing and horizontal advection are potentially important contributors to the seasonal evolution of CSST in the bay. From the A VHRR and SeaWiFS data, it is found that offshore conditions between the bay and Eno Island are different due to the presence of the Ojika Peninsula. It is also shown that the temporal behaviors of SSTs in the bay are closely connected with the air-sea heat flux and offshore conditions.