• Journal of The Geomorphological Association of Korea
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• v.27 no.3
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• pp.53-73
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• 2020

Morphology and grain size distribution of coastal dunes should be well documented because they are critical to dune's buffering capacity and resilience against storm surges. The nationwide coastal dune survey produced the dataset, including beach-dune topographic profiles and grain size parameters for frontal beaches, foredunes, and inland dunes. This research investigated the dataset to describe geomorphic and textural properties of coastal dunes: foredune slopes, dune heights above approximately highest high water, mean size, and sorting, together with associated variables of coastal setting that influence coastal dunes. It also explores the possibility of a dune type scheme based on gran size trends. The results are as follows. First, the coast in which dunes are developed is the primary control on foredune morphology and sediment texture. Coastal dunes on the east coast were developed more alongshore rather than inland, with gentler slopes on the higher ground and out of coarser sand. The shore aspect contributes to this pattern because the east coast cannot benefit from prevailing northwesterly. Second, grain size trends from beaches through foredunes to inland dunes were little identified. Third, 12 dune types were identified from 69 dunes, showing the indicative capability for the status of beaches and dunes. We confirmed that the dataset could increase our understanding of the overall characteristics of coastal dune morphology and texture, though there is something to be improved, for example, establishing the refined and comprehensive field survey protocol.

• 한국해양학회지
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• v.23 no.3
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• pp.123-129
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• 1988

The toxicity of bivalves in the Korean waters was investigated during 1987-1988. The toxicity of paralytic shellfish poison (PSP) was found in the sea mussels (Mytilus edulis galloprovincialis, M. corsucus), scallops (Patinopecten yessoensis, Chlamys farreri), tellin (Peronidia venulosa) and venus clam (Ruditapes philippinarum) among the 28 species screened. The toxicity in mussels, scallop (C. farreri) and venus clam was mainly confirmed from the samples collected around Jindong Bay in the southern coast of the peninsula, whereas the toxicities of tellin and scallop (P. yessoensis) were found in the vicinity of Pohang in the east coast. Samples from the west coast showed low levels of toxicity than those from the east arid south coasts. Although it varied with the regions, the toxicity was detected mainly during April to June, exceptionally during May to August in Pohang. The levels of toxicity were generally below the criteria of 4 mouse unit (MU)/g edible portion in foreign countries, with few exceptions.

• Journal of Navigation and Port Research
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• v.30 no.4
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• pp.295-302
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• 2006

This study is to integratedly examine coastal management policy and marine tourism development project for Korean coasts, especially for the South Sea of high development pressure, presenting sustainable tourism development policies for the future. To do so, it is examined central government-level coastal development projects set up by the Ministry of Culture and Tourism, the Ministry of Maritime Affairs and Fisheries and the Ministry cf Construction and Transportation, setting the direction of south coastal management and tourism development at a level of national territory planning. The problems of coastal management first and then the problems of the South Coast Tourism Belt Project are analyzed in order to present political and administrative alternatives. To overcome such problems and make Korea a marine tourism base in East Asia, there is a need for re-recognition of the value of the project and its continuous push through cooperation between central and local governments. Also, under the presupposition of consensus building among local people and the sustainable development of environments, there should be are-recognition that the future cf Korean marine tourism in the 21st-century and the success of an inverted $\pi-axis$ national development depend on the South coastal Tourism Belt Development Project.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.3
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• pp.105-114
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• 1997

Wind is one of the main forcing contributing the circulation of the East Sea. By using 1.5-layer and 2.5-layer reduced gravity models, circulation in the East Sea is simulated. The bifurcation of the Tsushima Warm Current (TWC), the separation of East Korea Warm Current (EKWC) from the east coast of Korea, the Nearshore Branch of TWC, and the cyclonic gyres stretched from the East Korea Bay to the northern half of the East Sea are compared well with the schematic map. The features of the upper and the lower layer are very similar except for those of the central region. The Polar Front is the separating line of two different features. The main feature of northern part of the East Sea, north of the Polar Front is cyclonic gyres, which are composed of three cyclonic gyres in most seasons. North Korean Cold Current (NKCC) and Liman Cold Current (LCC) are the nearshore part of these cyclonic gyres. In the south of the Polar Front the current systems of both layers are anticyclonic in most seasons, except that those of the upper layer in winter and spring are not anticyclonic. Along the coast of Korea and Russia, the velocity structure is barotropic, while that of the central region is baroclinic. The effects due to the seasonal variations of wind stress and local Ekman suction/pumping are studied by imposing the domain with modified wind stress. which is spatial mean with temporal variations and temporal mean with spatial variations. It is found that the local Ekman suction/pumping due to wind stress curl is important to the formation of the cyclonic gyres in the western and the northwestern region of the East Sea.

• Atmosphere
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• v.16 no.1
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• pp.33-48
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• 2006

A classification of snowfall type based on development mechanism is proposed using previous snowfall studies, operational experiences, etc. Five types are proposed: snowfall caused by 1) airmass transformation (AT type), 2) terrain effects in a situation of expanding Siberian High (TE type), 3) precipitation systems associated with extratropical cyclones (EC type), 4) indirect effects of extratropical cyclones passing over the sea to the south of the Korean peninsula (ECS type), and 5) combined effects of TE and ECS types (COM type). Snowfall events during 1981-2001 are classified according to the 5 types mentioned above. For this, 118 events, with at least one station with daily snowfall depth greater than 20 cm, are selected. For the classification, synoptic weather charts, satellite images, and precipitation data are used. For TE and COM types, local sea-level pressure chart is also used to confirm the presence of condition for TE type (this is done for events in 1990 and thereafter). The classification shows that 109 out of 118 events can be classified as one of the 5 types. In the remaining 8 events, heavy snowfall occurred only in Ullung Island. Its occurrence may be due to one or more of the following mechanism: airmass transformation, mesoscale cyclones and/or mesoscale convergence over the East Sea, etc. Each type shows different characteristics in location of snowfall and composition of precipitation (i.e., dry snow, rain, and mixed precipitation). The AT-type snowfall occurs mostly in the west coast, Jeju and Ullung Islands whereas the TE-type snowfall occurs in the East coast especially over the Young Dong area. The ECS-type snowfall occurs mostly over the southern part of the peninsula and some east cost area (sometimes, whole south Korea depending on the location of cyclones). The EC- and COM-type snowfalls occur in wider area, often whole south Korea. Precipitation composition also varies with the type. The AT-type has a snow ratio (SR) higher than the mean value. The TE- and EC-type have SR similar to the mean. The ECS- and COM-type have SR values smaller than the mean. Generally the SR values at high latitude and mountainous areas are higher than those at the other areas. The SR value informs the characteristics of the precipitation composition. An SR value larger than 10 means that all precipitation is composed of snow whereas a zero SR value means that all precipitation is composed of rain.

• 한국해양학회지
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• v.20 no.1
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• pp.12-21
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• 1985

In this paper, the most important oceangraphic phenomena of the summer season in the East China Sea are reviewed. The hydrographic conditions in the suface layer above the seasonal thermocline are under great influence from solar heating, fresh water runoff mainly from the Yangtze River, and summer wind fields. In the lower layer below the thermocline, several distinct water masses e.g. the Kuroshio surface water, the Western North Pacific Central Water and the Yellow Sea Bottom Cold Water are intruded in response to the adjustment of the field of mass to the various dynamical processes. The frontal mixing between the intruded Yellow Sea Bottom Cold. Water and the Western North Pacific Central Water takes place in the bottom layer over the continental shelf south off Cheju Is. This mixed water probably has mush influence on the water properties of the intermediate and bottom layer around Cheju Is. and the south coast of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.208-217
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• 2021

This study described the fishing characteristics of Pacific herring Clupea pallasii and examined the relationship between its catch and sea temperature in Korean waters from 1970 to 2019. Although the herring catch in Korean waters stayed below 1,000 tons per year from the mid-1970s to mid-1980s, the catch in the winters in the East Sea of Korea started to increase markedly after 1987-1988, when the sea surface temperature (SST) seemed to shift to a warmer regime. Since the mid-2000s, overall, herring was caught throughout the year in the East Sea and eastern South Sea of Korea, and its catch significantly increased by around 30,000 tons per year. The main fishing grounds of herring in the poor fishing years until the mid-1980s were possibly formed in the western offshore of Korea, and subsequently the fishing grounds were distributed in the eastern coast of Korea. While the standardized catch per unit effort (CPUE) for two main fisheries of herring catch was significantly correlated with the herring catch since the 2000s, there was a gradual decline since the 2010s. The herring catch in the East Sea had significant positive correlations with SSTs, but that in the West Sea had a significant negative correlation.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.411-420
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• 2015

This study examined methods for stand density control by using shape ratio (tree height/DBH) and its application for effective management of Pinus thunbergii coastal disaster prevention forests. We analyzed the present conditions (height, DBH, and density) of P. thunbergii coastal disaster prevention forests at 123 study sites on Jeju Island and west, south, and east coasts of South Korea and compared them with results from previous studies. The average shape ratio for P. thunbergii showed positive correlations with stand density and was significantly higher on the west coast (66.32) than on the south (49.57) and east (48.19) coasts and Jeju Island (48.29). Stands with shape ratio higher than 70 accounted for 50% of the total study sites on the west coast, indicating a decrease in their disaster prevention function compared to that of other previous studies. The stand density in most coastal areas, except the east coast, was significantly higher than the standards recommended by the Korea Forest Service and the Forestry and Forest Products Research Institute of Japan, indicating the need for stand density control. According to the growth estimation equation for P. thunbergii in the coastal area of South Korea, density control is required for young stands less than 14 years old, which show drastic increase in the shape ratio, to conserve their disaster prevention function. Particularly, the first thinning of P. thunbergii forests should be implemented before the stand age of 8 years that a shape ratio exceeds 70. For disaster-prone young stands (${\leq}20cm$ DBH) of P. thunbergii, the stand density was higher in the standard of Japan considering shape ratio than in that of Korea aiming timber production. Hence, the standard guidelines employed in Japan, which assign higher importance to disaster prevention function based on field surveys, can be applied effectively for controlling the stand density of P. thunbergii coastal forests in South Korea, to improve their disaster prevention function.

• Journal of Species Research
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• v.6 no.spc
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• pp.75-93
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• 2017

As a part of a survey of indigenous biological resources of Korea, 30 marine benthic foraminiferal species belonging to 24 genera and seven orders (Astrorhizida, Lagenida, Lituolida, Miliolida, Robertinida, Rotaliida and Textulariida) were identified. Bottom sediment samples were collected from eight stations on the west and east coast of South Korea, in April 2015 and May 2016, respectively. Ten species belonging to nine genera and five orders (Lagenida, Lituolida, Robertinida, Rotaliida, Textulariida) were identified in the Yellow Sea. Among these taxa, Rotaliida was the dominant order, represented by four species: Evolvocassidulina tenuis (Phleger & Parker, 1951), Cibicides mabahethi Said, 1949, Cibicides pseudolabatulus Perelis & Reiss, 1975 and Cibicidoides barnetti Bermudez, 1949. Twenty species belonging to 15 genera and five orders (Astrorhizida, Lagenida, Lituolida, Miliolida, and Rotaliida) were identified from the East Sea and the Lagenida was the dominant order, represented by 11 species: Lagena strumosa Reuss, 1858, Lagena nebulosa (Cushman, 1923), Lagena striata var. semiornata Reuss, 1863, Procerolagena cylindrocostata Albani & Yassini, 1989, Fissurina bispinata $Ujii{\acute{e}}$, 1963, Oolina laevigata d'Orbigny, 1839, Polymorphina amplissima McCulloch, 1977, Polymorphina subelliptica McCulloch, 1977, Guttulina succincta McCulloch, 1977, Guttulina neoproblema McCulloch, 1977 and Lagenosolenia obtecta McCulloch, 1977. The findings described here increased the number of foraminiferal species in Korea to approximately 1060, and contribute to our understanding of the diversity of foraminifera in Korean waters.

• The Journal of Fisheries Business Administration
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• v.35 no.2
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• pp.91-115
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• 2004

The main purpose of this study is to analyze the cooperative squid fisheries problems surrounding the $E128^{\circ}$, established by the 1965 Korea - Japan Fisheries Agreement which banned Korean large trawlers' fishing east to the $E128^{\circ}$ In fact, the moratorium was put on by Japans request. However, such issue did not occur until the filefish stock in the southern Korean sea, which was a major target fish species of the large trawl fisheries, The filefish stock collapsed completely around 1991 and at the same time most of bottom fish stocks in the East China Sea began to show a symptom of over - exploitation. Thus, the off - shore large trawlers learned to have a little opportunity of finding out alternative fish stocks as well as fishing grounds. Fortunately, at that time squid resource stock and consumption were on the increasing trend. The large trawl fisheries were able to economically exploit squid stock east to the $E128^{\circ}$ through cooperative fishing with squid angling light boats in the East and East - South Sea, even though such cooperative fishing activities violate the existing fishery laws apparently. Some important reasons that the large trawlers have continued the cooperative fishing seem to be because (ⅰ) squid resource stock has been on the increasing state over time, (ⅱ) the trawl fisheries have made a significant contribution to meeting domestic and export demands and stabilizing squid prices, and (ⅲ) they have kept domestic squid market from foreign competition. However, the new Korea - Japan fisheries agreement in 1998 provided a momentum of questioning the effectiveness of the $E128^{\circ}$ by the squid - related fisheries other than the squid angling. Serious conflicts between squid - related fisheries began to emerge and to be much intensified. Squid angling industries in the East opposed to large trawlers's efforts to formalize such illegal cooperative squid fishing activities. Their main argument was that such formalizing would definitely make the East coast squid prices lower and in turn their business performance would be worse off. The results of quantitative analysis suggest that the trawlers' massive landing may have a significant influence on lowering the east coast squid prices. Now, an important issue that the squid - related fisheries and the government are facing is to solve such complex squid fishing problems through a multi - participatory negotiation process, including price stabilization, total allowable catch level and its operation schemes, $E128^{\circ}$ rearrangement, and so on.