• The Korean Journal of Malacology
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• v.28 no.1
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• pp.1-6
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• 2012

We studied that the effect of stocking density on growth and survival rate of the scallop, Chlamys farreri (initial shell height 32.97 mm and total weight 5.63 g) from June 2002 to October 2003 in the west coast of Korea. C. farreri is usually the west coast of Korea and northern China in the natural habitat of the coastal species. Range of surface water temperature in the study area was $4.3^{\circ}C$ to $25.3^{\circ}C$, salinity 29.2 psu to 32.1 psu, dissolved oxygen 5.32 mg/L to 7.51 mg/L and pH was 7.84 to 8.12, respectively. The stocking densities were 20, 30, 40 and 50 individuals per a compartment of suspension cage in culture beginning. After 16 months from initiation, ranges of shell height and mean total weight were from 64.35 mm to 76.23 mm and from 41.53 g to 64.85 g. The survival rate was from 82% to 100%. The growth rate of the scallop was negatively correlated with the stocking density. The growth of the shell height and total weight were decreased with decreasing of water temperature. Most of mortality of scallop occurred during March to April and September to October. Survival rate in the stocking density was decreased by density increase and was highest in 20 individual a compartment.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.138-150
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• 2003

In the mid-west coast of Korea where Mankyung and Dongjin rivers discharge fresh water, Saemangeum tidal dyke of 33 km long is under construction to reclaim the very shallow estuary region of 41,000ha. Main source of freshwater in this coastal area is Keum River locating closely north of the dyke. At present, the dyke connected with Gogunsan-Gundo separates this area into three regions; northwestern, southwestern and eastern (Saemangeum) region of the dyke, and the water in Saemangeum region is exchanged through one gap in the northern dyke and two gaps in the southern dyke. We have observed distributions and structures of temperature and salinity to examine the summer circulation related with low-salinity water in this coastal area in 1998 and 1999. In the surface layer off the northern dyke a tongue-like distribution of low-salinity extends 60 km long from Keum River estuary mouth to the northwest, forming plume front bounded by offshore water. In the inner region of Saemangeum dykes salinity distributions show that two river waters are merged together and the low salinity water is deflected toward northern gap of the dyke. In the surface layer off the southern dyke we observed small tongue-like distribution of another low-salinity water extending to the north from Gomso Bay. Based on the analysis of distributions of low-salinity water and frontal structures, we can suggest an anticlockwise circulation of coastal water around the dyke, composed by the estuarine water outgoing from the inner region of the dyke through the northern dyke's gap and the inflow through two gaps of southern dyke from offshore. After completing the dyke construction, this coastal circulation around the dyke will be, however, changed because fresh water discharge of Mankyung and Dongjin rivers will be routed artificially and directly into the area offshore of the southern dyke.

• 한국해양학회지
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• v.7 no.2
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• pp.59-73
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• 1972

The heavy minerals of a barred estuarine and lagoonal sediments along the North Carolina coast have been studied with more than one hundred samples. Currents, salinity, and pH exhibit well-developed gradients from the upstream parts of the estuaries on the west toward the open ocean on the east. Twenty- four heavy minerals were identified in sediments of the study area. However, less than half of these occur frequently and the remainder exist only in minor quantities or trace amounts. Heavy minerals usually comprise less than 1% of the sample but vary from sample to sample. The maximum amount of heavy minerals in sediments of sounds and estuaries is 2.4% and in sediments of Outer Banks is 16.7%. Opaque minerals range from 10 to 85% of the total heavy mineral assemblage. Garnet and sillimanite are relatively more abundant in the eastern part than the western part in the area. Garnet more abundant in the northern part than the southern part, whereas sillimanite is more abundant in the southern part than the northern part, because the garnet source is in the northern part and one of the sillimanite source is in the southern part in the study area. The results of heavy mineral study indicate that the source of sediments is the Blue Ridge and Piedmont crystalline complex, and Coastal Plain formations. Some portions of sediments are transported from the Atlantic Ocean by the landward currents. They further indicate that the sediments of the Atlantic coast in the study area are transported mainly from the northern part to southern part by longshore littoral currents, and some portions of sediments are transported from the southern part to the northern part by the Gulf Stream.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.335-344
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• 2014

To understand the drift-diffusion of HAB(Harmful Algal Bloom) in this paper, we used three-dimensional hydrodynamic model POM(Pringceton Ocean Model) and Lagrangian particle track module. First, the results of residual flow that considered tide, wind, temperature, salinity, and TWC(Tsushima Warm Current) effect was tend to northeast in the coastal area and the flow in the offshore region showed results similar to TWC. To understand of HAB's movement, released each area that southern Kamak bay(Case 1), Mijo coast(Case 2), and southern Mireukdo coast(Case 3) assumption that red tide occurred. The areas where the HAB occurs frequently. As a result of HAB occurred in southern Kamak Bay(Case 1), mainly drifts to Narodo coast and Yeoja bay that located on the west side. Case 2 was mainly drifts to Yokjido coast and Saryangdo coast Especially, HAB occurred in Mireukdo coast(Case 3) relatively many particles drift to eastward as the influence of the TWC.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.293-303
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• 1999

Fish fauna of fishes collected from the Saemankum area in the west coast of Chollabuk-do was studied from October 1996 to April 1999. The specimens collected from the five sites in this area were identified into 107 species belonging to 83 genera and 52 families. Of them the largest group of fishes was order Perciformes, comprising 50 species and 21 families, and showed 46.7% in total numbers of species. Next larger groups were orders Scorpaeniformes and Pleuronectiformes containing 16 and 14 species respectively. In this area, the group comprising a lots of species was the family Gobiidae taking 13 species, and next groups were the families of Sciaenidae (6 species), Engraulidae (5 species) and Pleulonectidae (5 species). The dominant species was Engraulis japonicus which is 23.4 ％ in total indiyidual numbers, and subdominant species was Thryssa kummazensis which is 18.5%. The important species economically in the Saemankum area were Anguilla japonica, E. japonicus, T. kummalensis, Konosirus punctatus, Sardinella zunasi, Mugil cephalus, Argyrosomus argentatus, Pseudosciaena polyactis, Collichthys lucidus, Paralichthys olivuceus and Cynoglossus joyneri. The species of high frequency in this area from February to June every year were Anguilla japonica, E. japonicus, T. kammalensis, K. punctatus, S. zunasi, Coilia nasus, Syngnatuus schlegeli, P. polyactis, C. lucidus and Pholis fangi. Ophichthus rotundus, Repomucenus leucopoecitus and R. koreanus were Korean endemic species in the west coast of Chollabuk-do. On the other hand, Boleophthalmus pectinirostris was not found during this study, and Periophthalmus modertus, Tridentiger barbatus and Lophogobius ocellioauda sharply decreased in individual numbers in comparison to several years ago.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.148-156
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• 2002

The coastline of Hampyung Bay, southwestern coast of Korea, was examined and measured in the field for the understanding of geomorphic changes and sea-cliff erosion processes. The Hampyung-Bay coastline is characterized by steep-face slope and soft soil and/or intensively weathered rock composition. Saw teeth-shaped coastline, and relict weathered basement-rock and "Island Stack" exposed on the beach surface are peculiar geomorphic features indicating active sea-cliff erosion. The coastline in the study area is continuously retreating with the following cyclic process: erosion of cliff base, gravitational landslide or mass wasting, formation of talus, and then erosion and removal of talus. In this study, sea-level rise during summer in the west coast of Korea is suggested as one of the key factors fur the removal of soil taluses and, thereby, accelerating sea-cliff erosion.f erosion.

• Journal of the Korean Geographical Society
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• v.37 no.5
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• pp.511-521
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• 2002

Coastal sand dunes in West coast of Korea are under stress. Due to the newly constructed Seohaean(West Coast) Highways, the number of visitors and the anthropogenic pressures will keep rising in near future. Sea level rise due to the global warming may cause a lot of damage to the natural resources and residents of coastal area. Therefore, many countries including United States are doing nationwide coastline survey using highly sophisticated methodology. In this study, high resolution IKONOS satellite images along with aerial photographs taken since 1960's have been sequentially analyzed using GIS software (Erdas Imagine 8.3). Onsite monitoring has been performed at the 31 measuring points in 10 beaches since the May of 2001 in order to measure the sand budget. Post-construction monitoring after installation of sand fences is also being done on sites regularly. Restoration works seem to be effective at this moment.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.493-500
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• 2013

Comparisons of surface sediment distributions in summer 1997 and 2011 and elevations on the tidal flats in April 1998 and March 2013 had been used for understanding the long-term changes of sedimentary environments at southern Kanghwa tidal flat, west coast of Korea. The mud sediments dominated in the eastern part and sandy mud sediments dominated in the western part of the tidal flat in 1997. In 2011, the surface sediments were dominant mud and sandy mud at Sunduri and Tonggum in the eastern part, sandy mud at Tongmakri in the middle part, and sand and muddy sand at Yeochari and Changhwari tidal flats in the western part. The area of mud sediments had decreased, but that of sand-mud mixed sediments extended to eastward tidal flat for 14 years. The long-term topographic changes showed that deposition occurred at Tongmakri and Yeochari and erosion occurred at Changhwari tidal flat during 15 years. These changes should be effected the local hydrodynamic changes by several constructions near the tidal flat since the 1990s.

• Atmosphere
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• v.28 no.1
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• pp.53-67
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• 2018

This study examined the lake effect of the Yellow Sea which was induced by the Siberian High pressure system moving over the open waters. The development mechanism of the convective cells over the ocean was studied in detail using the Weather Research and Forecasting model. Numerical experiments consist of the control experiment (CTL) and an experiment changing the yellow sea to dry land (EXP). The CTL simulation result showed distinct high area of relative vorticity, convergence and low-level atmospheric instability than that of the EXP. The result indicates that large surface vorticity and convergence induced vertical motion and low level instability over the ocean when the arctic Siberian air mass moved south over the Yellow Sea. The sensible heat flux at the sea surface gradually decreased while latent heat flux gradually increased. At the beginning stage of air mass modification, sensible heat was the main energy source for convective cell generation. However, in the later stage, latent heat became the main energy source for the development of convective cells. In conclusion, the mechanism of the west coast heavy snowfall caused by modification of the Siberian air mass over the Yellow Sea can be explained by air-sea interaction instability in the following order: (a) cyclonic vorticity caused by diabatic heating induce Ekman pumping and convergence at the surface, (b) sensible heat at the sea surface produce convection, and (c) this leads to latent heat release, and the development of convective cells. The overall process is a manifestation of air-sea interaction and enhancement of convection from positive feedback mechanism.

• 한국해양학회지
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• v.20 no.1
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• pp.43-49
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• 1985

The Changgu Bay, a macrotidal coastal embayment of the west coast of Korea, is an area of extensive intertidal sedimentation. Three types of major sediment facies are identified based on grain size analysis: silt, sandy-silt, and silty-sand facies. It is found that intertidal sediment facies comprise a continuum of progressively finer sediments from lower flat to upper one. The X-radiography of the cores in the intertidal zone show a wide variety of physical and biogenic sedimentary structures. The major structures include bioturbation, current ripple and parallel-laminae. Bioturbations are observed in all core samples, especially in the silt flat zone. The degree of bioturbation increases laterally from sandy facies (low tide level) to silt facies (high tide level) due to favorable properties of fine mud for organisms. The ripple laminae, composed of current ripple foresets, characterize the silty-sand and sandy-silt flats. The parallel laminae are extensively bioturbated, and two types of laminae are distinguishable; thick-laminae with a thickness of 1 to 5mm and thin-laminae with a thickness of less than 1mm.