• 한국수산과학회지
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• 제48권4호
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• pp.529-541
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• 2015

We examined the species composition and community structure of demersal fish in the middle and southern coastal waters of the East Sea of Korea by surveying a commercial Danish seine fishery from 2010 to 2013. We considered the waters north of $37^{\circ}N$ as middle and those south of $37^{\circ}N$ as southern waters. A total of 79 demersal fish species belonging to 18 families were collected. Of these, 59 species (77.6%) inhabited only the East Sea as opposed to the West and South Seas of Korea, and most were resident species. The species and biomass were similar between the two portions of the study area. The sandfish Arctoscopus japonicus (78.0%) and the blackfin flounder Glyptocephalus stelleri (65.1%) were the most common species and accounted for the most biomass in the middle and southern waters, respectively. Fish were most abundant at shallow depths (50-100 m) in the middle portion of the East Sea. Using a cluster analysis, we divided the species composition and community structure at the sampling stations into three groups: middle portion (group A), deep area of the southern portion (group B), and shallow areas of the southern portion (group C). A. japonicas and G. stelleri were dominant in groups A and B, while G. stelleri and Clupea pallasii were dominant in group C.

• 한국수산과학회지
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• 제47권3호
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• pp.255-263
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• 2014

We investigated the reproductive characteristics of Lycodes tanakae in the coastal waters of the middle East Sea to elucidate the species' population structure. We investigated Lycodes tanakae maturation and spawning based on samples collected by Danish seine and gill nets from January 2012 to December 2013. We analyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. The spawning period was December to February, while fecundity ranged from 1,677 eggs at 57.3 cm (total length;TL) to 6,445 eggs at 75.7 cm. The relationship between TL and fecundity (F) was $F_e=6E-05TL^{3.127}$ ($R^2$ = 0.516), and F increased with increasing TL. We estimated the TL at 50% group maturity as 60.4 cm for females and 59.8 cm for males. This study is the first report of Lycodes tanakae reproductive characteristics in the coastal waters of the middle East Sea.

• 수산해양교육연구
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• 제27권4호
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• pp.1053-1062
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• 2015

This research assesses the implementation of the bilateral fisheries order of the China-Japan fisheries agreement. After establishment of UNCLOS, the China-Japanese fisheries agreement has played as a basis for the fisheries order in the East China Sea. The China-Japanese fisheries agreement intends that the fisheries industries in China and Japan can utilize the renewable natural resources in the East China Sea. As the EEZ of China overlaps with that of Japanese in the East China Sea, the two countries established the China-Japan Provisional Measure Zone and Middle Zone in the Sea. Even though the three coastal States (e.g. Korea, China, and Japan) in the East China Sea are involved in managing these zones, there has been little effort to coordinate each county's management. Additionally, the Taiwan-Japan fisheries agreement, which is for the area of N $27^{\circ}$, has made costal States to establish and implement united measures to conduct effective fisheries management. Regarding access to the joint fishing zone in EEZ, Chinese fisheries regulations have been enforced in the zone because the fishing capacity of China exceeds all of other countries, reducing the number of fishing licenses and catch quotas. It turned out that a nation that has authority over fisheries resources tends to establish specific conditions of fishing operations to maximize its national interest. In the China-Japan Provisional Measure Zone, Chinese and Japanese authorities have introduced united measures to manage fisheries resources. However, in the Middle Zone between China and Japan, there is no regulation on fishing; both countries' fishing vessels can have free access to the zone. Thus, it is recommended that one should introduce an international fisheries management regime for the Middle Zone. In this regard, Korea should play a leading role in establishing the international management regime because Korea has middle position in terms of geographical standpoint, the degree of dependence on commercial fishing, and its fishing capacity.

• 한국항해학회지
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• 제14권2호
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• pp.61-76
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• 1990

하계 대한 해협 서수도에는 연직적으로 특성이 서로 다른 세개의 수괴가 존재한다. 그 중 중층수에 대하여 인접 해역의 해수 특성과 상호 비교함으로써 그 기원과 유로를 추정하였다. 그 결과, (1) 중층수는 동지나 해의 대륙붕 상에서 형성된 Kuroshio수와 중국 대륙 연안수와의 혼합수인 것으로 나타났다. (2) 중층수는 Kyushu Island 의 서쪽 해역, 경도 약 127 E 부근 해역과 제주도와 Goto Islands의 사이 해역을 거쳐 유입된 것으로 나타났다.

• Animal Systematics, Evolution and Diversity
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• 제38권4호
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• pp.205-213
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• 2022

A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

• 한국해양학회지:바다
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• 제18권3호
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• pp.131-141
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• 2013

본 연구는 2011년 9월에서 12월까지 동해(북부, 중부, 남부), 서해, 동중국해의 해구에서 각각 채집된 살오징어의 계군을 형태 및 유전학 차이를 이용하여 구분하였다. 형태학적 차이에 따른 계군분석은 평균성숙외투장(20-22 cm)을 기준으로 하여 발생시기를 구분하였고, 유전학적 특성에 따른 계군은 mtDNA COI 영역의 염기변이에 의한 유전자 다양성을 이용하여 확인하였다. 본 연구 결과 평균성숙외투장을 기준으로 동해 북부는 발생시기가 하계군, 나머지 집단(동해 중부, 동해 남부, 동중국해 북부, 서해 북부)은 추계군으로 크게 2개의 계군으로 추정되었다. 유전자 분석결과 살오징어 mtDNA COI 영역에서 총 49개의 haplotype을 확인하였다. TCS 분석결과 haplotype 유전자형 네트워크가 star-like형태이며, 모든 집단에서 유전적 다양성(haplotype diversity, h)이 높고(h=0.661~0.841), 반면에 염기 다양도(nucleotide diversity, ${\pi}$)가 낮게 나타난 점으로 미루어보아 국내 서식 살오징어의 경우 최근에 급속한 집단의 분화가 이루어진 것으로 판단된다. Pairwise Fst를 이용한 집단분석결과 비록 모든 집단간의 유전적 차이가 낮게 나타났지만(Fst = 0.001~0.043) 평균성숙외투장 기준으로 같은 추계군으로 분류된 집단(동해 중부, 동해남부, 서해 북부)간에는 유전적 차이를 확인할 수 있었다(P<0.05).

• 한국어류학회지
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• 제32권4호
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• pp.245-250
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• 2020

가자미목 가자미과에 속하는 Atheresthes evermanni 2개체(표준체장 407~438 mm)가 동해 중부 고성군 연안에서 자망으로 채집되었다. 본 개체는 입이 크고 양안간격이 좁으며, 무안측에서 눈이 보이지 않고 새파는 가늘고 길며, 꼬리지느러미는 만입형이고 측선은 거의 직선인 특징을 가지고 있다. 우리나라 해역에서 A. evermanni는 처음 기록되고, 본 종을 우리나라 어류상에 포함시키며 새로운 속명과 국명으로 각각 '화살치가자미속' 및 '화살치가자미'를 제안한다.

• 수산해양기술연구
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• 제41권4호
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• pp.306-315
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• 2005

The distribution and composition of marine floating debris were recorded from a training ship 'Kyeongyang' of Gangwon Provincial University at May 19-29, 2004 and Aug.24-31, 2004. The sampled area is the middle part of East Sea of Korea(the coast of Gangwondo and region of Ulleung island and Tokdo), divided into 27 unit segments on survey areas. Debris fabrication materials were categorized with 6 items using the following; styrofoam, paper & cardboard, net & rope, vinyl & plastic, floating metal & glass, man-made or natural wood. From the investigation on May,2004, total numbers of marine floating debris in the middle part of the East Sea of Korea was 996 individuals. The No. 1 and No. 2 unit segment located at south-west region of Ulleung Island showed higher density than others. The styrofoam and vinyl & plastic accounted for 72.8% of all debris fabrication materials. From the investigation on August, 2004, total numbers of marine floating debris in the coast of the Gangwondo of Korea was 2,473 individuals. The No. 13 and No. 14 unit segment located at the vicinity of Samcheok showed higher density than others. The styrofoam and vinyl & plastic amounted to 76.1%. In the coast of the Gangwondo, the vinyl & plastic showed the highest density of 6 items were 41.3% and 68.0% on May and August, respectively. The total numbers of marine floating debris on May and August were 3,399 individuals. Vinyl & plastic accounted for 59.4%(2,019 ind.) among all debris, next styrofoam 15.8%(537 ind.) and wood 11.2%(379 ind.).

• 한국수산과학회지
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• 제46권6호
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• pp.843-850
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• 2013

The feeding habits of Lycodes tanakae Eelpout were studied with 722 specimens collected from March 2011 to December 2012 in the coastal waters of the middle East Sea. The main prey of L. tanakae were fish, molluscs and arthropods. Nevertheless annelida, echinodermata and others were found in small amounts in the stomach contents. The L. tanakae stomach was empty of contents in 50.9% of specimens. While smaller size specimens of L. tanakae (less than 40 cm) fed mainly on euphausiids and amphipods, the larger specimens (more than 40 cm) fed on the fish Allolepis hollandi and Icelus cataphractus, and the molluscs Berryteuthis magister and Watasenia scintillans. The main prey items of L. tanakae varied seasonally. The fish Lycodes nakamurai was the dominat prey from November to January during its spawning season. Euphausiids and amphipods of the arthropods were the dominant prey from February to April. The molluscs Berryteuthis magister and Watasenia scintillans were the dominant prey from May to September. The diversity index (H') of diets showed variations by length class and month; the highest values were 2.61 in the length class of 51-55 cm, and the monthly highest were 2.68 in September with 23 species and 2.65 in November with 18 species. The highest dominance index (D') of diets was 0.57 in the length class of 31-35 cm, and the monthly highest was 0.71 in February. Cluster analysis divided prey groups into four groups by length class and three groups by monthly prey items. The gonad index gradually increased during the process of maturation while, contrary, stomach content index decreased during this period.

• Acta Via Serica
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• 제3권2호
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• pp.23-48
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• 2018

The Silk Road usually implies a network of trade and communications that stretched from east to west and connected China and the countries of the Far East via Central Asia and the Middle East to the eastern Mediterranean, or through the northern coast of the Caspian Sea and the Volga basin to the Black Sea coast. However, at certain historical stages, a network of maritime and overland routes stretching from north to south, commonly called the Volga-Caspian trade route, also played a significant role in international trade and cultural contacts. The geopolitical realities of the early Middle Ages relating to the relationship of Byzantium, the Sassanid Empire, and the West Turkic Khaganate, the advance of the Arab Caliphate to the north, the spread of Islam in the Volga region, the glories and fall of the Khazar State, and the Scandinavian campaigns in the Caucasus, closely intertwined with the history of transport and communications connecting the north and south through the Volga-Caspian route. In a later era, the interests of the Mongolian Uluses, and then the political and economic aspirations of the Ottoman Empire, the Safavid State, and Russia, collided or combined on these routes. The article discusses trade contacts existing between the north and the south in the 15th and first half of the 17th century along the routes on the western coast of the Caspian Sea.