• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.561-569
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• 2013

EOF analysis of tidal residual derived from 2003~2009 tide data was used to identify the spatio-temporal variability. The effect of sea surface air pressures and winds on the tidal residual was also investigated by the correlation analysis. The first mode accounting for 68 % of the total variance represented concurrent sea level rise or fall, and the second mode accounting for 21 % of the total variance explained alternative sea level rise and fall between West Sea coast and both South Sea and East Sea coasts. While northerly and southerly winds dominated the tidal residual in the eastern coast of Yellow Sea, the effect of sea surface air pressures on the tidal residual increased along the coastal regions from South Sea to East Sea.

• Journal of The Geomorphological Association of Korea
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• v.17 no.1
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• pp.1-14
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• 2010

This paper deals with the classification and distribution of geomorphic surfaces and analysis on effects of geomorphic processes on the landforms in the inaccessable DMZ (Demilitarized Zone) to Wonsan Bay of East Sea coast of Chugaryeong Rift Valley, Central Korea. DEM (Digital Elevation Model) and Landsat images are used for the above anlaysis. The geomorphic surfaces are classified by TPI (Topographical Position Index) for the analysis of the convexity and concavity calculated using topographical elements such as elevation, steepness, and relief. In the Chugayreong Valley, 10 geomorphic surfaces are classified as steep valley, shallow valley, upland drainage, U-shaped valley, plain, open slope, upper slope, local ridge, midslope ridge, and high ridge. Zonal Statistics presents average characteristics of geomorphological processes of surfaces by the relationships between bedrock and relief, surface and relief, and between surface and NDVI. So, these analysis can help to understand geomorphological process such as dissection of lava plateau and watershed divide evolution.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.203-203
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• 2020

동해안에 위치한 영동지역은 산지로 둘러싸여 있어 지형적인 여건으로 지상강우관측망의 밀도가 낮으며, 지상관측소의 관측한계를 보완하기 위해 사용되고 있는 기존 대형 레이더는 지형 차폐로 인해 영동지역에서는 정확한 강우정보를 관측하기 어렵다. 강우정보는 홍수예측을 위해 필수적인 정보이므로, 집중호우와 태풍으로 인한 홍수재해가 빈번히 발생하는 영동지역에서는 관측공백의 해소가 필요하다. 이를 위해 환경부에서는 동해안 지역에 2기의 전파강수관측소를 설치, 운영 중에 있다. 해당 관측소 자료는 30km 관측반경 범위 내에서 수 백 미터 이하의 격자 강우자료를 생산할 수 있는 장점이 있다. 본 연구에서는 전파강수관측소의 자료를 강우 및 홍수 재해정보 생산에 활용하고자 한다. 대상지역은 영동지역에 위치한 삼척오십천으로 해당 지역은 친수적으로 조성되어 강우로 인한 시민의 인명피해가 위험이 존재하는 곳이다. 본 연구에서는 새로 설치된 삼척 전파강수관측소로 관측된 자료를 이용하여 고해상도 격자 및 유역평균강우정보를 생산하고, 지역특성을 반영하여 강우정보 기반으로 하천홍수 위험을 판단할 수 있는 하천흐름계산도표를 개발하여 평가하고자 한다. 생산된 고해상도 격자 강우자료는 70m 격자 해상도를 갖으며, 분포형 비차등위상차를 이용하여 추정된 강우정보이다. 유역평균강우는 삼척오십천 유역과 삼척시 동단위 행정구역별로 산출된다. 또한 하천흐름계산도표는 삼척오십천 유역의 현장답사를 통해 시민의 접근성, 하천수위 급상승으로 인한 피해가능성을 고려하여 6개 지점을 선정하여 개발하고, 전파강수관측소 관측강우정보를 활용하여 홍수예측정보로의 적절성을 평가한다.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.282-290
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• 2011

Two species of demersal fish, Liparis tessellates (cubed snailfish) and Hemitripterus villosus (shaggy sea raven), were investigated in relation to seasonal chemical composition. Total fat contents of the two fish were very low and were not appreciably different throughout the year, whereas their fatty acid compositions were significantly different depending on season. Noticeable changes in the moisture and protein contents in the two fishes were observed before and after spawning. Cubed snailfish showed relatively high amounts of total amino acids and free amino acids during summer months, whereas the levels of those in shaggy sea raven remained relatively unchanged throughout the year. Regardless of season, the major fatty acid of the two fishes was palmitic acid and most of polyunsaturated fatty acids (PUFAs) were n-3 PUFAs. Lead was over the legislative limit in some samples of the two fishes.

• 한국해양학회지
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• v.26 no.1
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• pp.83-100
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• 1991

A layer of salinity-minimum which characterizes the East Sea intermediate Water (ESIW) is found at an approximate depth of 200 m in three CTD section taken in the Ulleung Basin on May 17-21, 1988. Properties at this layer vary in ranges of $1.1^{\circ}C except at stations near the east coast of Korea where temperature is as high as $4.39^{\circ}C$ and salinity is as low as $33.992{\textperthousand}$. To be distinguished from the ESIW the East Sea Proper Water (ESPW) may be characterized by temperature less than $1^{\circ}C$, Salinity at the saliently-minimum layer and 500db increases southward in general, implying that the cold waters, both ESIW and ESPW, formed in the northern basin of the East Sea are spreading southward below the permanent thermocline in the basin. Hydrography in the Ulleung Basin is very similar to that in the Alboran Sea, suggesting a possibility of an anticyclonic circulation in the Ulleung Basin which is controlled strongly by the shoaling bottom.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.4
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• pp.548-561
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• 2019

The surfgrass Phyllospadix japonicus is a dominant seagrass species playing critical ecological roles on the eastern coast of Korea. However, few studies have been conducted on the ecological characteristics of this species, generally due to the turbulent water conditions in its habitat. In this study, to examine the growth dynamics of P. japonicus, we investigated monthly changes in morphological characteristics, density, biomass, and leaf productivity as well as changes in the underwater irradiance, water temperature, and water column nutrient concentrations of its habitat from August 2017 to July 2018. Underwater irradiance and water temperature showed clear seasonal changes increasing in spring and summer and decreasing in fall and winter. Nutrient availability fluctuated substantially, but did not display any distinct seasonal trend. Morphological characteristics, shoot density, biomass, and leaf productivities of P. japonicus exhibited significant seasonal variations, increasing in spring and decreasing in fall months. Spadix of P. japonicus occurred from March to August, with the maximum spadix percentage(15.8%) occurred in May 2018. The average leaf productivity of P. japonicus per shoot and area were 2.1 mg sht^-1 d^-1 and 7.5 g m^-2 d^-1, respectively. The optimum water temperature for the growth of P. japonicus in this study was between 13-14℃. The productivity of P. japonicus was not correlated with underwater irradiance, water temperature and nutrient concentrations. These results suggest that the study site provide sufficient amount of underwater irradiance, suitable water temperature range and nutrients for the growth of P. japonicus.

• Korean Journal of Ecology and Environment
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• v.48 no.1
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• pp.1-11
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• 2015

Abstract The purpose of study is to identify the relationship between stable isotope composition of reed stems in coastal and understand the structure of the fish community in 10 lagoons along the East Sea. The fish species composition (particularly, anadromous fish species) and relative abundance of trophic guilds was influenced by difference of geomorphic characteristics among lagoons. Reed stems ${\delta}^{13}C$ and ${\delta}^{15}N$ values ranged from $-28.40{\pm}0.11$‰ to $-26.87{\pm}0.25$‰ and $-1.09{\pm}1.45$‰ to $12.08{\pm}0.53$‰, respectively. The differences in reed stem ${\delta}^{15}N$ values might be associated with anthropogenic landuse and the geomorphic characteristics among lagoons. These results provide useful information to improve the conservation of fish habitats (biodiversity), preserve lagoon habitats and contribute to watershed management effect against anthropogenic pollution from watershed in these lagoon ecosystems.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.249-258
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• 2019

The goal of this study was to isolate and characterize the wild yeast strains in the soils of Hajodae and Gyungpodae Beaches, Gyungpo Lake in Kangwon-do, Korea and evaluate their anti-demential and tyrosinase inhibitory activities. Among the 27 yeast strains isolated from 30 soil samples from Hajodae Beach, Cyberlindnera culbertsonii HJ31-1, Dothichiza pithyophila HJ22-4, Metschnikowia bicuspidata HJ16-1, and Sakaguchia cladiensis HJ14-1 were recorded for the first time in Korea. Additionally, six of the 55 wild yeast strains isolated from 45 soil samples from Gyungpodae Beach and Gyungpo Lake had not previously been detected in Korea, such as Aureobasidium melanogenum JR3-1. The microbiological characteristics and anti-demential and tyrosinase inhibitory activities of these previously unrecorded yeasts were investigated. Almost all of them were oval-shaped and had ascospores except for Dothichiza pithyophila HJ22-4, Diutina siamensis JR37-5, and Canadida gelsemii DC 35-1. Furthermore, they were all sugar-tolerant and able to grow in 20% glucose-containing YPD broth, except for Cyberlindnera culbertsonii HJ31-1. Diutina siamensis JR37-5 had the highest tyrosinase inhibitory activity (30.9%).

• Economic and Environmental Geology
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• v.54 no.6
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• pp.699-707
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• 2021

Hwajinpo Lagoon, located on the eastern coast of Korea, is a unique environment where freshwater and saltwater are mixed. Systematic management of the lagoon is required because it is a biodiversity-rich and area of high conservation value. The existing environment of the lagoon was evaluated by identifying the distribution of the groundwater level and groundwater flow characteristics. In addition, hydrogeochemical fluctuations were analyzed to determine the effect of seawater intrusion into the aquifer. The results demonstrate that the freshwater-saltwater interface is distributed throughout the aquifer and rises when water of the lagoon evaporates due to prolonged periods of low rainfall and high temperature, thereby increasing the possibility of seawater inflow through groundwater. As for the ionic delta properties (difference between the measured and theoretical concentration of mixed waters), it was estimated that the cation-exchange and precipitation reactions occurred in the aquifer due to seawater intrusion. The ratio of seawater mixed at each point was calculated, using oxygen isotopes and chloride as tracers, resulting in an average of 0.3 and a maximum of 0.87. The overall seawater mixing ratio appears to be distributed according to the distance from the coast. However, some of the results were deviated from the theoretical expectations and reflected the characteristics of the nearby aquifers. Further research on seasonal changes and simulation of seawater intrusion mechanisms is required for specific analysis.

• Water for future
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• v.8 no.2
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• pp.65-74
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• 1975

The east coast seems to have remarkably different features from the west and south coast in the geographical, geomorphological, and oceanographical senses. In this paper the auther wishes to introduce some results of investigation morphological characteristics of the river mouth in the east coast an of analysis of it's causes. There are various closing form in river mouth by many causes, but the east coast hs the same closing form(the ratio of closing; roughly 0.18), as well known, by the sand spit, and has not hydrological but littoral drift background. The river of the east coast is proved mature age from hypsometric analysis. The wave and longshore current must be principal factor to be considered, in the analysis of the closing phenomenon owing to littoral drift. The research of the blown sand is considered valuable for the next study of this subject.