• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.44-55
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• 1996

This study was first performed since 1933 to investigate the flora of $\check{O}$ch$\check{o}$ng Island located in the middle part of Yellow Sea. A number of vascular plants recognized through in this survey were 319 taxa belonging to 78 families, 213 genera, 279 species, 38 varieties and 2 forma in which 38 species were newly recorded and 26 species of evergreen plant were identified. The Pteridophyta distributed in this island were 10 species and the naturalized plants were 4 species. And the coefficient of cryptogram(Pte-Q) and Urbanization Index(UI) as to the destruction degree of natural vegetation showed a value of 0.81, 3.64 respectively. Some noticeable species were Kadsura japonica, Castanopsis cuspidate var. thunbergii, Dendropanax morbifera, and Ficus stipulate and $\check{O}$ch$\check{o}$ng Island was considered as the northern limit of distribution of these species.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.295-303
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• 2003

The tidal flat area of south and west coast consists of 2.4% of total land area of Korea. About 83% of tidal flat is located at the west coast, and the remaining tidal flat is located at the south coast. This tidal flat is also divided for administrative regions which are Gyeonggi Province(35.1%), Chungnam Province(12.7%) Jeonbuk Province(4.7%), Jeonnam Province(44.0%) and Gyeongnam Province(3.5%). The tidal flat of west coast of Korea is one of the most important stopover site for shorebirds on the East Asia-Australia Flyway. The tidal flat is used for feeding and resting place by migratory shorebirds. Generally, waterbirds including migratory shorebirds are considered as key species to show the superiority of wetland. By the criteria of Lamsar Convention in the basis of waterbird, at least 14 coastal wetlands in Korea have to be internationally important wetlands. The factors to affect the distribution of shorebirds at the certain tidal flat are closely related with 1) the distribution of benthic invertebrates, potential prey of shorebirds 2) the availability of roosting site 3) the size of tidal flat 4) the intensity of human disturbance. In this paper, we summarized the regional status of tidal flat of Korea and its conservation methods related with migratory waterbirds.

• The Journal of Fisheries Business Administration
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• v.35 no.1
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• pp.133-168
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• 2004

The purpose of this study is to examine the state and characteristic of seafood marketing in Korean West Coast during the colonial period ruled by Japan. To accomplish the purpose, we tried to set the fisheries statistical database by reviewing of $\boxDr$Statistical Annual Report of Chosun Chongdokbu$\boxUl$ and $\boxDr$Official Report of Chosun Chongdokbu$\boxUl$. A trend analysis was carried out with the data. Also, by reviewing of articles related to the state of seafood marketing via $\boxDr$Daehan Maeil Newspaper$\boxUl$, $\boxDr$Maeil Newspaper$\boxUl$ issued at the period, we could find out some meaningful findings which backed up the statistics in realistic facts. For numbers of businessman in seafood marketing, it was clear that the number of Japanese businessmen increased more quickly than that of Korean compared with other sphere of fisheries. That means Japanese grasped Korean seafood market in a short time. In price of seafood in terms of cities, Kunsan was comparatively higher than Incheon and Mokpo. In price of seafood in terms of species, ‘Snapper’ was mostexpensive, and ‘Mackerel Pike’, ‘Anchovy’, ‘Mullet’, ‘Eel’, ‘Flatfish’ followed in that order. In price of a species in terms of ‘Yellow Croaker’, which was famous in West Sea, ‘Croaker with salt’ was more expensive than dried and fresh one. For the transition trend of number of fish market, we could ascertain that the number of market increased until 1919, however, it decreased slowly from 1932. That means Japanese government went to war against China from 1931. Of the West Coast, the number of fish market in Chungnam province was most high, but that of Chonbuk outrun from 1940. At that time, the number of fish market in West Coast reached to 34% out of that of whole country. In 1919, the proportion of seafood sales amount of West Coast neighboring provinces, such as Kyunggido, Chungnam, and Chonbuk, was 23% of whole country which rose to 28% in 1929, and 29% in 1939. Therefore, we could assure that seafood marketing was very active at that time in the region. When we consider the trend of seafood export at the main ports of West Coast, in 1910's, the export through Mokpo and Inchon port was very live but that of Kunsan was very tiny. However, in 1920's, the export amount of Inchon port did not much change, but that of Mokpo decreased, whereas, that of Kunsan increased. In the early and middle of 1910' s which was around beginning of Japanese ruling period, we realized that the imperialist Japan was very eager in political efforts to enhance the mind of seafood's quality improvement through the opening of several fisheries competitive shows and fairs.

• Korean Journal of Ichthyology
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• v.6 no.2
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• pp.93-98
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• 1994

The pipefish Syngnathus schelegeli was reared in the laboratory from May to June 1991 and observed the morphology of eggs and larvae squeezed from the parent fish(male). The diameter of inseminated eggs ranged from 0.72 to 1.01 mm (n=50), and yolk in yellow color were found in the eggs. The newly beared larvae were 10.9 mm in average standard length and had 59~60 myomeres. In 6 days after bearing, the post larvae attained 13.8 mm in average standard length and the low jaw was developed. The larvae of 14.1 mm in average standard length (8 days after bearing) had 40~42 fin rays in dorsal fin, 9 in caudal fin and 13~14 in pectoral fin. The juvenile of 14.7 mm in average standard length (10 days after bearing) had the well elongated snout along with the opercular and caudal fin similar to adult stage's.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.4
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• pp.313-325
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• 2011

Finite element grid system using h-refinement on the Yellow Sea was constructed based on previous study (Suh, 1999b) from 14 K to 210 K and special attention was concentrated on refining the coastal zone. In grid generation, depth change between adjacent points and non-dimensional tidal wave length ratio were considered. As a result approximately a quarter of the total nodes are located nearby 5 m of shallow area. Accurate bathymetry data using 30's and ETOPO1 with open boundary conditions of 8 major tidal constituents extracted automatically from FES2004 have been applied. In tidal simulation a 3-dimensional nonlinear harmonic model was setup and tidal amplification due to changes in vertical turbulent and bottom friction were simulated. In this study not only 8 major tidal constituents but also nonlinear shallow tides $M_4,$, $MS_4$ and long period $M_f,$, $M_{sf}$ were reproduced. It is found that implication of spatial variation of friction coefficient plays a very important role in reproduction of astronomical and shallow tides which are computed by iterative computation of nonlinear terms. Also it should be considered differently with respect to tidal periods. To understand the distribution of tidal asymmetry, amplitude ratio of $M_4/M_2$ and phase differences $2g(M_2)-g(M_4)$ were calculated. Tidal distortion ratio marks up to 0.2 on the west coast showing shallow coastal characteristics and somewhat wide range of ebb-dominances in front of Mokpo area are reproduced.

• Journal of Korea Water Resources Association
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• v.39 no.2 s.163
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• pp.139-150
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• 2006

In recent, increasing of the impervious area gives rise to short concentration time and high peak discharge comparing with natural watershed and it is a cause of urban flood damage. Therefore, we have performed for structural and non-structural plans to reduce the damage from inundation. The Gulpo-cheon basin had been frequently inundated and damaged due to the water level of Han river. So, the Gulpo-cheon floodway was constructed with 20 meters width for flood control in the basin but it was not enough for our expectation and now we have a plan to expand the floodway to 80 meters. We use a XP-SWMM model developed based on EPA-SWMM version for analyzing the capacity of flood conveyance by the expansion of Gulpo-cheon floodway with the same 100 years return period design storm and the same tidal conditions of the Yellow sea. The flood conveyance after the expansion of floodway becomes three times comparing it with before the expansion. Also we simulate the flood discharge at the diversion point of Gulpo-cheon for the expanded condition of floodway and know that the discharge of about 300 m3/sec is flowing backward to the expanded floodway. Therefore we may need some kinds of hydraulic structures to prevent the back water.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.6
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• pp.353-360
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• 2010

The Kyunggi Bay in mid-west of Korea is a relatively large estuarine system that connects the Han River system with Yellow Sea. Due to macro-tidal range of more than 8 m, the urban estuary shows deep tidal channels and wide tidal flats. Since last 30 years, the coastal development is undergoing, yielding noticeable change in environment. Particularly the tidal flat dynamics are generally accepted as being related with tidal residual flows in this area (Kim et al., 2009). We have estimated the annual variation and vertical structure of residual currents with one-year long observed flows in two major tidal channels of Kyunggi Bay. The moving average method and tidal current harmonic analysis yield nearly the same results on residual flow. The residual flow in Jangbong channel ranges from 20 cm/s in summer to 30 cm/s in winter. It is noticeable that the residual flow in Jangbong channel is flood dominant throughout the year, while the flow in Seokmo channel is ebb-dominant residual flow with current speed range of 20-40 cm/s. Due to the baroclinic response of relatively shallow estuary, significant reduction of energy in bottom layers have been observed, indicating the importance of residual circulation to the tidal flat behavior.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.1
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• pp.39-47
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• 2020

In order to investigate current characteristics at the Gungpyung beach, which is a macrotidal flat, field measurements were carried out in the summer and winter at the intertidal and the subtidal zones. The distribution of residual current at intertidal flat was dominant in the northward direction in the summer and dominant in the northward and southwestern directions in the winter. The direction and speed of the residual current in the winter are highly correlated with the significant wave height, and the turbidity is also highly correlated with the significant wave height. Therefore, in the winter, high sediment rates are suspended by high waves, and sediments are transporting due to the residual current in the southwest direction. On the other hand, it is expected that the northward residual current is predominant due to the small wave in the summer, and sediment transport does not occur largely due to less suspended sediments. In addition, sediment transport in the southern direction is blocked by the dock, which is the artificial structure, and the erosion occurs in the south side of the dock. The erosion pattern in the macrotidal zone of Yellow sea is dominated by seasonal waves, and blocking of sediments by artificial structure is very important.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.101-108
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• 2013

Ara Canal is the first artificial canal in Korea that connects the Han River and the Yellow Sea. Due to mixture of waters with different salinity and water quality, complicated hydrodynamic and water quality distributions are expected to occur inside the canal. An integrated hydrodynamic and water quality modeling system was developed using the 3 dimensional hydrodynamic model, EFDC (Environmental Fluid Dynamics Code) and the water quality model WASP (Water Quality Analysis and Simulation Program). According to the modeling results, BOD, TN, TP and Chl-a concentrations inside the canal were lower at the West Gate side than the Han River side since influent concentrations of the West Gate side are significantly lower. Chemical stratification due to salinity difference were more evident at the West Gate side as vertical salinity difference were more pronounced in this area. On the other hand, Chl-a concentrations showed more pronounced vertical distribution at the Han River side as Chl-a concentrations were higher in this area. It was notable that Dissolved Oxygen concentrations can be lower than 2 mg/L occasionally in the middle part of the canal. While major factor affecting DO concentrations in the canal are inflows via both gates, the other important factor was found to be BOD decay in the canal due to extended hydraulic residence time. This study can be used to predict hydrodynamic conditions and water quality in the canal during the year and thus can be helpful in the development of gate operation method of the canal.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.179-186
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• 1995

Human anisakiasis may occur after ingestion of raw marine flesh infected with nematode larvae of Anlsi,hidae. Anisakiasis caused by the migration of the larva into the wall of stomach, small intestine and other portion has been reported in Korea. This prospective study was made of all cases referred to parasitological laboratory in Cheju-do between. Tune 1989 and June 1992. Gastric anisakiasis was confirmed if larvae invading the gastric wall were observed by gastrofiberscopy One hundred and seven cases were diagnosed, most of which were in 30-49 years old. Most of the patients complained acute epigastric pain with history of eating raw marine fish. This symptom usually occurred about 12 hours to 1 day after ingestion of infected marine fish. Edema, erosion or ulcer of the mucosa and hemorrhage from the gastric wall were observed in the involved areas. Ninety larvae removed from the stomach were identified; the larva of Anisqkis siwlex was the most prevalent species, and the Iarva of Pseudntewanoua decipien was also detected. The important species of marine fish from which the patients became infected was demonstrated as yellow corvina, sea eel, ling, cuttle fish, yellowtail and others. Five species of marine fish as a possible source of infection were examined, and Anisakis simplex larvae and Pseunotewqnoua decipirens larvae were collected from the mackerel and rock cod. This study demonstrates that anisakiasis is recognized as a public health problem in Korea.