• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.177-184
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• 2003

Numerical simulation on marine wind and sea surface elevation was carried out using both three-dimensional hydrostatic and non-hydrostatic models and a simple oceanic model from 0900 LST, August 13 to 0900 LST, August 15, 1995. As daytime easterly meso-scale sea-breeze from the eastern sea penetrates Kangnung city in the center part as basin and goes up along the slope of Mt. Taegullyang in the west, it confronts synoptic-scale westerly wind blowing over the top of the mountain at the mid of the eastern slope and then the resultant wind produces an upper level westerly return flow toward the East Sea. In a narrow band of weak surface wind within 10km of the coastal sea, wind stress is generally small, less than l${\times}$10E-2 Pa and it reaches 2 ${\times}$ 10E-2 Pa to the 35 km. Positive wind stress curl of 15 $\times$ 10E-5Pa $m^{-1}$ still exists in the same band and corresponds to the ascent of 70 em from the sea level. This is due to the generation of northerly wind driven current with a speed of 11 m $S^{-1}$ along the coast under the influence of south-easterly wind and makes an intrusion of warm waters from the southern sea into the northern coast, such as the East Korea Warm Current. On the other hand, even if nighttime downslope windstorm of 14m/s associated with both mountain wind and land-breeze produces the development of internal gravity waves with a hydraulic jump motion of air near the coastal inland surface, the surface wind in the coastal sea is relatively moderate south-westerly wind, resulting in moderate wind stress. Negative wind stress curl in the coast causes the subsidence of the sea surface of 15 em along the coast and south-westerly coastal surface wind drives alongshore south-easterly wind driven current, opposite to the daytime one. Then, it causes the intrusion of cold waters like the North Korea Cold Current in the northern coastal sea into the narrow band of the southern coastal sea. However, the band of positive wind stress curl at the distance of 30km away from the coast toward further offshore area can also cause the uprising of sea waters and the intrusion of warm waters from the southern sea toward the northern sea (northerly wind driven current), resulting in a counter-clockwise wind driven current. These clockwise and counter-clockwise currents much induce the formation of low clouds containing fog and drizzle in the coastal region.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.160-169
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• 2019

The migration status of waterbirds inhabiting the 10 coastal wetlands in the south and west coasts (Jangbongdo, Muuido, Daecheoncheon estuary, Seocheon tidal flat, Yubudo, Gomso bay, Hauido, Jeungdo, Doam bay, Gangjin bay) was examined from May 2008 to March 2013. For the most dominant taxonomical group, shorebirds accounted for 37.5% of the number of species and 67.1% of the total population, followed in the order of dabbling ducks, herons, and seagulls. The dominate species were Calidris alpina, Larus crassirostris, Limosa lapponica, Charadrius alexandrinus, and Calidris tenuirostris. Shorebirds were observed most at Seocheon Tidal Flats and Yubudo Island, and dabbling ducks were found most in Doam Bay. Diving ducks were observed most at Gangjin Bay and seagulls were seen most frequently at Seocheon Tidal Flats. The ten coastal wetlands of the western and southern coasts were divided into three groups according to the similarity index of waterbirds (Ro). Group 1 was the area where dabbling ducks and diving ducks were dominant, group 2 was the area where shorebirds were dominant, and group 3 was the area where seagulls were dominant. It was evident that there were differences in species composition depending on the regional environments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.3
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• pp.286-292
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• 2017

The Coastal VTS will be continuously constructed to prevent marine traffic accidents in the coastal waters of the Republic of Korea. In order to provide the best traffic information service to the ship operator, it is important to understand the navigation risk factor. In this study, we analyzed the navigational hazards of Gunsan coastal area where the coastal VTS will be constructed until 2020. For this purpose, major traffic flows of merchant ships and density of vessels engaged in fishing were analyzed. This study was conducted by Automatic Identification System (AIS) and Vessel Pass (V-PASS) data. The grid intervals are 10 minute ${\times}$ 10 minute (latitude ${\times}$ longitude) based on the section of the sea. A total of 30 sections were analyzed by constructing a grid. As a result of the analysis, the major traffic flows of the merchant vessels in the coastal area of Gunsan were surveyed from north to south toward Incheon, Pyeongtaek, Daesan, Yeosu, Pusan and Ulsan, and from east to west in the port of Gunsan Port, 173-3, 173-6, 173-8, 183-2, 183-5, 183-8, 183-3, 184-1 and 184-2. As a result of the study, the fishing boats in Gunsan coastal area mainly operated in spring and autumn. On the other hand, the main traffic flow of merchant ships and the distribution of fishing vessels continue to overlap from March to June, so special attention should be paid to the control during this period.

• Economic and Environmental Geology
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• v.54 no.5
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• pp.535-547
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• 2021

Aggregate is an essential construction material, and the demand is increasing every year. Aggregate has different properties in each region, and it is difficult to supply it over long distances due to its quantity and weight. For the stabilization of aggregate supply and demand, regional aggregate resource surveys have been conducted since 1993 in Korea. In this study, an aggregate resource survey was conducted in Goyang City to understand the characteristics of aggregate distribution as part of the annual regional aggregate resource survey in 2020. Goyang City has a high mountainous area to the east, and the southwestern part shows a topography where a wide flatland develops. It has 18 small streams originated from the eastern mountainuos area and 1 large stream Han River. The drilling data shows that thickness of the Quaternary deposits tend to deepen toward the south. The aggregate reserves are relatively abundant, the depth of the aggregates are relatively deep. Changes in the depth of the Quaternary deposits and the amount of aggregate in Goyang are seems to be closely related to the activities of the Han River rather than the sedimentation characteristics from the upstream to the downstream of the small streams. This characteristics show a similar tendency to the distribution of aggregates in adjacent regions to the west coast in Korea. Therefore, the regions that close to west coast have a high probability of aggregate reserves around relatively large-scale streams flowing into the west coast.

• Korean Journal of Medicinal Crop Science
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• v.11 no.3
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• pp.212-215
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• 2003

There were so many Asparagus cochinchinensis (Lour.) Merr. in the past in Korea. Now a day, it is under diminishing circumstance because of over exploitation for pharmacy materials. The amount of domestic market demand of it was imported. The autochthonous planting areas were mainly surveyed along coastal region and island. Autochthonous A. cochinchinensis was mainly distributed in sea shore below 1km from sea and founded 26 regions among 45 surveyed regions. Northern and eastern limited distribution of A. cochinchinensis was $N36^{\circ}15'$ in the west coast and $E128^{\circ}02'$ in the south coast of Korean peninsula, respectively. But it was not founded in the east coastal region. Dominant vegetation of surveyed area was pine with shrub. The number of tuberous roots of A. cochinchinensis growing in good light penetration was more than growing in bad light penetration.

• Ocean and Polar Research
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• v.33 no.1
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• pp.1-11
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• 2011

This study describes measurements of fast ice recorded on May 23, 2009, in Kongsfjorden (translated as 'Kongs Fjord'), an inlet on the west coast of Spitsbergen in the Svalbard Archipelago. Seasonal fast ice is an important feature for Svalbard fjords, both in relation to their physical environment and also the local ecosystem, since it grows seaward from the coast and remains in place throughout the winter. Ice thickness, snow, ice properties, and wind speed were measured, while SAR (Synthetic Aperture Radar) data was observed simultaneously observed two times from ALOS-PALSAR (L-band). Measured ice thickness was about 25-35 cm while the thickness of ice floe broken from fast ice was measured as 10-15 cm. Average salinity was 1.9-2.0 ppt during the melting period. Polarimetric data was used to extract H/A/alpha-angle parameters of fast ice, ice floe, snow and glacier, which was classified into 18 classes based on these parameters. It was established that the area of fast ice represents surface scattering which indicates low and medium entropy surface scatters such as Bragg and random surfaces, while fast ice covered with snow belongs to a zone of low entropy surface scattering similar to snow-covered land surfaces. The results of this study will contribute to various interpretations of interrelationships between H/A/alpha parameters and the wave scattering Phenomenon of sea ice.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.28 no.6
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• pp.350-360
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• 2016

In order to investigate characteristics of waves and currents varying in space in the Haeundae coast in winter, numerical simulations by using a 2-D spectral wave model(SWAN) and 2-DH hydrodynamic model(Delft3D) were carried out in this study. The results of numerical simulations were validated with the field data collected at several different locations in the study area in February, 2014. From the numerical simulations, it was found that waves and currents were significantly influenced in terms of direction and magnitude by bottom topography characterized by straggling rock crops covered with sea grasses. The coupling of SWAN and Delft3D models also revealed that alongshore currents directing from the east to the west were developed in the nearshore, due to the influence of larger waves with the main incident direction from the east.

• Journal of Species Research
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• v.12 no.2
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• pp.165-173
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• 2023

Bacterial communities inhabiting islands play a vital role in the functioning and formation of a unique, isolated ecosystem. Nevertheless, there has been a lack of systematic research on the indigenous microbiological resources of the islands in Korea. To excavate microbial resources for further studies on the metabolism and biotechnological potential, a standard dilution plating was applied to coastal seawater samples collected from islands along the west coast of the Korean Peninsula, including Deokjeokdo, Baengnyeongdo, and Daebudo in 2022. A total of 2,007 bacterial strains were isolated from the samples as single colonies and identified using 16S rRNA gene sequence analyses. A total of 20 strains, with ≥98.7% 16S rRNA gene sequence similarity to bacterial species having validly published names but not reported in Korea, were designated as unrecorded bacterial species in Korea. The unrecorded bacterial strains were phylogenetically diverse and belonged to four phyla, five classes, 12 orders, 17 families, and 18 genera. The unreported species were assigned to Algimonas, Amylibacter, Notoacmeibacter, Roseibium, and Terasakiella of the class Alphaproteobacteria; Alteromonas, Congregibacter, Marinagarivorans, Marinicella, Oceanospirillum, Psychromonas, Thalassotalea, Umboniibacter, and Vibrio of the class Gammaproteobacteria; Lutibacter and Owenweeksia of the class Flavobacteriia; Paenibacillus of the class Bacilli; and Pelagicoccus of the class Opitutae. The taxonomic characteristics of the unreported species, including morphology, biochemistry, and phylogenetic position are provided in detail.

• Journal of The Geomorphological Association of Korea
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• v.26 no.2
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• pp.39-54
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• 2019

In this paper, based on evidence of coastal sediment, we show that erosion and sedimentation environments are very sensitive to sea level changes during the Medieval Warm Period (MWP) and the Little Ice Age (LIA). We identified four sedimentary units(4.57-3.07m), which formed in the Dark Age Cool Period (DACP), MWP and LIA were classified based on the lithostratigraphy, grain size distribution, magnetic susceptibility and geochemistry of a drilling core taken from the west coast of Hwaseong City. The unconformity surfaces as boundaries of the units were also identified by the lithostratigraphy shown on the drilling core. We propoese that sedimentation was dominant in the area during the periods of sea level rise, whereas erosion prevailed during the periods of sea level fall. Particularly, extreme events, such as floods and typhoons are believed to have accelerated these processes, and we found the associated evidence in sediments of two units. This study provides an example of estimating the relative sea level variation using coastal sediments and may be useful for studying past sea level changes around the Korean Peninsula.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.133-147
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• 2004

Environmental quality(water and sediment) was analyzed in the tidal flat of Saemangum of Jeonbuk Province, the west coast of Korea, using the 101 sediment samples and 69 water samples collected in September 4~13, 2001. Major water quality parameters with the means of 69 surface water samples are as follows; $25.51{\pm}0.68^{\circ}C$ for water temperature, $29.88{\pm}5.01$ for salinity, $1.40{\pm}0.78mg/L$ for COD, $0.352{\pm}0.417mg/L$ for DIN, and $0.027{\pm}0.023mg/L$ for phosphate, respectively. Higher values were found at the subestuary of Dongjin and Mangyung River, and lower values at the Saemangum embayment and Gomso Bay. There was a significant negative correlation between salinity and the other water quality parameters(p<0.0001) such as COD, nutrients, SS and N/P. This correlation suggested that the major pollution sources be from terrestrial inputs through tributaries in this area. Principal component analysis clearly revealed a spatial variation of water quality; stations with higher values of nutrients and COD located subestuary of tributaries. 14 sediment quality parameters including 8 trace metals were measured using the 101 surface sediment samples. Average values for the parameters are as follows; Al $2.28{\pm}0.92%$, Cd $0.61{\pm}0.27ppm$, Cu $8.95{\pm}4.06ppm$, Fe $1.19{\pm}0.37%$, Mn $182.31{\pm}77.45ppm$, Ni $10.83{\pm}4.97ppm$, Pb $15.20{\pm}4.35ppm$, Zn $41.34{\pm}34.62ppm$, COD $2.68{\pm}1.85mg/g\;dry$, AVS $0.04{\pm}0.08mg/g\;dry$, IL $1.29{\pm}1.08%$, water content $24.11{\pm}4.49%$, TN $0.02{\pm}0.02%$, TC $0.22{\pm}0.30%$. Spatial variations of sediment quality were not clear as water quality. Some higher values were found at the subestuary of Gum River and lower values at the other area. There was a significant positive correlation between the heavy metal concentrations and organic materials within the sediment(p<0.05). Enrichment factors showed the ranges of 1~2 for most of the metals in the sediment except zinc(1~6), indicating no serious exogenous input of heavy metals in the study area. Also, the heavy metal concentrations in the sediment were within the ranges found at the natural marine environments.