• Journal of Fisheries and Marine Sciences Education
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• v.11 no.1
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• pp.24-42
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• 1999

I have studied historical transition process of fisheries industries, fisheries Institute in abreast of developing fisheries industries of west coast of Korea since 1910 year with regard to the Gogunsan Is. The results were summarized as follows. In 1910 year, fishery industry has been carried out shifting fishing gear e.g set-net in shallow waters, small stow net, small seine net adapting to the tophorgrapical feature, shape of coast, oceanic condition, however, the fishing gear and fishing method were undeveloped, so that, Japanese fishermen had been exploited fisheries resources penetrating the fishing ground. Most important species were lot of captured croaker, cod, spanish mackeral, sea abream, herring in coastal sea. nowaday, squid, anchovy, shrimp, crab, pompret were much captured. The species were captured in 18 century were not captured. It is rarely than that period. Fishereis aquatic culture had been not farmed till 1960 year, but sea laver, shrimp, crab, had been breeded 1970 year also, the fresh water fish e.g. eel, cat-fish had been breeded activately. The fisheries processing industry were composed of salt. icing, dry, method. the salted fish industry had been prevailed at Gangyng, Kwangchon, Kunsan, Julpo comparatively. The fisheries institute had been established at Kunsan at first, but institute established in other region had been abolished in a short time. This phenomenon was related with development of fisheries resources. The western coast fisheries industries had been wasted of decreasing of fisheries resources, variation of environment. Accordingly, the study of preserving the marine resources. educated man power who engaged in fisheries field have to accomplish. Sea was dying with reason of loss of mud in west coast factory waste, waste of life the increase of accident of sea polluted, each illegal fishing industry physical and chemical reason etc. in this respect, Kusan maritime college, fisheries developing agency, institute have to take important role for developing fishing industry.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.126-134
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• 2001

Several angular sandstone fragments (about 7 cm in longest diameter) occur in two piston cores, obtained from the submarine trough in the northeastern part of Korea Strait. The origin of the sandstone fragments and the paleoenvironment of trough sediment could be suggested from sedimentary facies analysis of cores and identification of ostracod within sandstone fragments. Echo characteristics around two core sites in submarine trough represent the prolonged bottom echoes with diffuse or no subbottom reflectors. The cores consist of a lower bioturbated mud and an upper gravelly sand sediments with sandstone/shell fragments. The bioturbated mud sediments show low water contents (27-44%) and high shear strength (19.2->37 kPa) compared with those of Holocene sediments (60-219% and 1.0-2.7 kPa, respectively) in the inner shelf and continental slope. However, clay contents (48-56%) of the bioturbated mud sediments are similar to those of fluviatile Holocene sediments in the inner shelf. The mean grain size of gravelly sand sediments ranges from 2.3 to 3.0 ${\phi}$ and shows coarsening upward with sandstone/shell fragments. The Holocene palimpsest in the continental shelf are composed of muddy sand sediments or sandy mud sediments (mean grain size: 4.6-7.6 ${\phi}$). Those suggest that two core sediments might be formed from Paleofluvial and paleocoastal deposits during sea-level lowstand. However, sandstone fragments mainly consist of quartz grains and bioclasts, with carbonate matrix, hollow pore, and glauconite. Two extinct ostracod species, Normanicythere sp. and Kotoracythere sp., are recovered in the sand-stone fragments of core EP-7, and they continued to exist from late Pliocene to early Pleistocene in cold water environment of this area. Thus, the sandstone fragments are interpreted to be formed at the paleocoastal environment derived from the Plio-Pleistocene outcrops exposed around the submarine trough during the LGM (Last Glacial Maximum) period.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.46-66
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• 2002

High-resolution multichannel seismic data were collected in the coastal area near the Gori nuclear power plant to investigate Quaternary fault pattern and timing. A 12 channel streamer, a sparker, and a portable recorder were used for data acquisition. Because the group interval of the streamer was 6.25 m and the sparker can generate acoustic waves with the frequency content of up to 500 Hz, the data show a significant improvement both in horizontal and vertical resolution. The area surveyed is covered with 30-40 m thick Holocene sediments that constitute the mud belt along the southeastern coast of Korea. The survey area is characterized by the well discriminated Pleistocene and Holocene boundary and shallow gas-charged zones. A number of Quaternary faults were found in the sediment column, that are nearly vertical and extend north-south. The Quaternary faults, arranged at a spacing of a few hundred meters, suggest that they were formed in response to compression, although some of them reveal extensional characteristics. Locally, faults disrupt Incised-channel fills that are interpreted to have formed in the early stage of transgression after the beginning of the Holocene. Seismic sections suggest that shallow gas in the mud belt sediments made its way upward through the fractured fault planes. The tectonism responsible for the opening of the East Sea has not persisted since the late Miocene, but vigorous Quaternary faulting activity in the vicinity of the southeastern Korean Peninsula indicates that tectonic stability has yet to be achieved in this region underlain by the hotter than normal mantle.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.2
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• pp.175-183
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• 2010

To understand the variation of macro benthos community according to the installation of structure and topographic placement in the shellfish farm on tidal flat, the practical example of the tidal shellfish growing area at Namsung-ri Goheung was observed. The results of the research for the field observation were summarized as follows. (1) The ground gradient of the shellfish farm was very flat below about $1^{\circ}$. The shellfish farm ground took the shape of $\sqcup$ from the shoreline to the place of 150 m seawards, and the shape of $\sqcap$ from there to the low tide line. During ebb tide, the $\sqcup$ shape ground stored the sea water, and the $\sqcap$ shape ground was supposed to act as the effect factor to leak slowly or to prevent the outflow. (2) The oyster shell bag or the type of riprap wall as the boundary in the shellfish farm was classified into five types. The air exposure time and flooding time were 181 and 434 minutes, respectively. (3) In the numerical experiment, the deep-sea water wave coming in the study area had 0.5 m of maximum wave height to show the very stable conditions and the wave direction pattern of S-direction was dominant at Naro great ridge, and SE, SSW and S-direction were distributed strongly around the shellfish farm. (4) By the grain size analysis, the sediment around tidal flat consisted of gravel 0.00~5.81(average 1.70)%, sand 14.15~18.39(average 13.23)%, silt 27.59~47.15(average 30.84)% and clay 35.79~55.73(average 36.19)%, and the sediment type was divided into (g)M(lightly gravelly mud), sM(sandy mud) and gM(gravelly mud) by Folk's diagram. (5) The macro benthos community survey conducted in this site in January, 2010 showed that 1 species of Mollusca, 8 species of Polychaeta and 2 species of Crustacea appeared, and 11 species occupying over 1% of total abundance were dominant.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.8-31
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• 2023

To understand the distribution and formation mechanism of benthic foraminiferal assemblages, grain size analysis, ¹⁴C radiocarbon dating, and benthic foraminifera analysis were conducted on thirty-two surface sediments collected from the continental shelf of the northern East China Sea, respectively. Surface sediment was composed of sandy mud~muddy sand facies with an average of 52.04% of sand, 13.72% of silt, and 34.20% of clay. These sedimentary facies are palimpsest sediment. Benthic foraminifera was classified into a total of 48 genera and 104 species, including agglutinated foraminifera, calcareous-hyaline, and calcareous-porcelaneous foraminifera. The production rate of agglutinated foraminifera increased toward the Yangtze River area while that of planktonic foraminifera increased toward Jeju Island. Dominant species are Ammonia ketienziensis, Bolivina robusta, Eggella advena, Eilohedra nipponica, Pseudorotalia gamardii, Pseudoparrella naraensis. ¹⁴C radiocarbon datings of Bolivina robusta and Pseudorotalia gamardii with the highest production rate were 2,360±40 yr B.P. and 2,450±40 yr B.P., respectively. In the result of cluster analysis, three assemblages composed of P. gaimardii, B. robusta, and A. ketienziensis-P. naraensis were classified broadly. P. gaimardii assemblage is thought to be formed from about 2.5 yr B.P. at the sea area of the Yangtze River to 50 m in water depth affected by fresh water. B. robusta assemblage is thought to be formed from about 2.4 yr B.P. at the sea area of Jeju Island to 50~100 m affected by offshore water. And then, A. ketienziensisP. naraensis assemblage was formed in the northwest sea area (Central Yellow Sea Mud). These distributions and composition of benthic foraminiferal assemblages formed from about 2.5 yr B.P. in the northern East China Sea are thought to be due to the change of benthic ecology environment that occurred by the sea level increase during the late Holocene.

• Journal of Environmental Science International
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• v.12 no.7
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• pp.735-744
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• 2003

The field observations on a seasonal characteristic of organic matter and its origin in the surface sediment were carried out at 35 stations in Deukryang bay, southern coast of Korean Peninsula from May 1995 to February 1996. The analytical parameters were mud temperature, ignition loss(IL), chemical oxygen demand(COD), pheopigment, sulfide and water content. The origin and seasonal dynamics of organic matter in Deukryang Bay were analyzed by COD/IL, COD/sulfide ratio and principal component analysis(PCA). As a results of the mud temperature fluctuated between 2.1$^{\circ}C$ with the lowest mean 4.6$^{\circ}C$ in winter and 27.6$^{\circ}C$ with the highest mean 25.5$^{\circ}C$ in summer. The range of ignition loss(IL) was from 3.1% in autumn to 21.5% in winter. Chemical oxygen demand(COD) showed the highest mean value of 8.45 mg/g dry in spring within the range of 2.90∼18.21 mg/g dry, while it showed the lowest value of 4.33 mg/g dry in autumn within the range of 0.67∼10.37 mg/g dry. Pheopigments showed the highest mean value of 9.04 $\mu\textrm{g}$/g dry in autumn within the range of 1.36∼20.44 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 2.20 $\mu\textrm{g}$/g dry in summer within the range of 0.33∼11.36 $\mu\textrm{g}$/g dry. The range of total sulfide (H$_2$S) was from no detect(ND) to 3.30 mg/g dry in spring. And water content showed the annual mean value of 43.6% within the range of 23.6∼54.9%. The source of organic matter by COD/IL and COD/sulfide ratio in Deukryang Bay had been producted by primary producer in sea water areas except the areas effected by small stream, domestic and animal wastes. And the analytical results of PCA was able to be divided into three different regions. The former was characterized by the shallow depth and authigenic organic matter from phytoplankton in northwest area and northeastern inner bay, the secondary was done by deeper depth and allochthonous one from lands in southeast area and eastern entrance of bay, and the latter was done by authigenic one from the farm of seaweeds such as, sea cabbage, sea mustard etc in western entrance of bay. But a study on the relationship between sulfide and COD concentration in the northeastern inner bay which was characterized by the water stagnation will to take much more studying including major constituents of organic matter in the future.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.2 no.1
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• pp.14-20
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• 1997

The southwestern continental shelf of the East Sea, Korea developed mud deposits as a belt in the inner shelf area from Pusan to Pohang. The general surface sediments consist of very poorly to poorly sorted muddy sediment. The differences of physical, geological and geomorphic conditions in the study area may control and produce distinctive foraminiferal populations. To establish a baseline of environment for the muddy sediments in the southwestern continental shelf of the East Sea, 17 stations were sampled and proved to contain 45 species of living benthic foraminifera. Analysis of the foraminiferal populations in cluster analysis recognized to five habitat zones. These habitat zones contain distinctive cooccurrences of the entire occurring species. Foraminiferal community composition appeared to be closely interrelated of water masses, depths, nutrients and sediment characters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.700-707
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• 2003

Surface sediments in the mouth area of Jinhae Bay were investigated to evaluate the benthic environment in terms of geochemical criteria and macrobenthos abundance. Characteristics of the surface sediment distribution exhibited muddy sediments in the most part of study area. Some mixed sediments of coarse sand and mud were distributed along the coastal area of Geoje Island and around the Jeo Islands. Organic matter from ignition loss and total organic carbon from CHNS varied between $8.8-1.7\%,\;and\;4.62-0.77\%,$ respectively. The source of organic matter based on the C/S ratio was mixed with in situ biogenic and terrigenous organic matter. The C/S ratio of organic matter also suggested both an anoxic bottom condition in several parts of the study area. The content of hydrogen sulfide in surface sediment was extremely variable and showed spatio-temporal variation from site to site. In several locations, the content of hydrogen sulfide as an index of eutrophication was over the critical value (0.2 mg/g), suggesting that several parts of the study area were not favorable for the habitat of macrobenthos. The relationship among the number of individuals of marcrobenthos, hydrogen sulfide, and organic matter was not clear, but a potential negative relationship between individuals of marcrobenthos and hydrogen sulfide was indicated.

• 한국해양학회지
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• v.26 no.1
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• pp.38-46
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• 1991

size data of 1,044 surface sediments from Korean shelf area were compiled and reexamined. Size distribution curves of the sediments are unimodal (31% of the total number), bimodal (54%), or multimodal 915%), Size curves of the sediments and modal subpopulations of the mixed sediments show resemblance to normal curve in shape. The modal mean value shows systematic change along a direction inside the Recent mud belts of the southeastern Yellow Sea and west of Korea Strait. It was found that the areas covered by unimodal sand are minimal value areas of heavy metal and suspended sediment-concentration in the southeastern Yellow Sea and northern East China transport processes during Recent time. It was also found that the mode analysis is useful method to extract information from sediment size data.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.501-503
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• 2007

오호츠크해 사할린 북동 해저사면지역은 세계적인 가스수화물 산출지역으로 알려져있다. 이미 2005년 탐사에서 50 cm 두께의 순수 가스수화물 시료를 해저면에서 채취한 지역이다. 2006년 탐사에서는 다양한 주파수대역의 고해상도 지구불리장비를 사용하여 탐사를 실시하였다. Side-scan Sonal와 3.5 kHz SBP 탐사, 수중음향 탐사를 통해 대규모 하도구조가 가스수화물지역의 북쪽 경계를 형성하고 있음을 밝혔다. 가스수화물의 BSR은 수심에 얕아짐에 따라 계속해서 심도가 감소하여 수심 약 300 m에서 해저면에 다다름. 이는 연구지역에서의 가스수화물 안정대의 상부경계가 약 300 m임을 시사한다 가스수화물 분출구조들은 약 1000m 수심을 경계로 천부에 분포하고, 해저면에는 원형의 가스분출구조들이 특징적으로 나타난다. 반면에 1000 m 수심보다 깊은 지역에서는 mud-dirpir의 상승구조로 판단되는 상승구조들이 해저면에 굴곡지형을 형성하고 있다. 해수중으로 분출하는 가스기둥들은 수심 111.2 m에서 1226.4 m 지점까지 다양한 수심에서 분포하며, 상승높이는 최대 750 m에 이르며, 약 150 m 수심까지 도달한다. 이는 해저에서 분출되는 메탄가스가 해수에 흡수되지 않고 해수면까지 이동하여 대기중으로 발출될 수 있음을 시사한다.