• 한국수산과학회지
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• 제56권5호
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• pp.684-690
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• 2023

This study was conducted bimonthly from February to December 2021 to reveal the ecology of Sargassum thunbergii in the intertidal zone along the coasts of Korea. Separate surveys on the period of embryo formation were conducted from February 2021 to December 2022. The growth of S. thunbergii began to increase in February, reached a maximum in June, and was at a minimum in October. Air vesicles were formed from February to June, April to August, and February to August on the east, west, and south coasts, respectively. Receptacles were observed from April to June on the east coast, but from April to August on the west and south coasts. The earliest release of embryos was observed in late May 2022 on the south coast, followed by early June on the east and west coasts. The average size of leaves, stems, and air vesicles was maximum on the east coast and minimum on the west coast, whereas leaf and internode intervals were maximum on the west coast and minimum on the east coast. Plant length, biomass, and the number of branches showed maximum values in the south coast and minimum values in the east coast.

• 물과 미래
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• 제8권2호
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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.

• ALGAE
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• 제33권1호
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• pp.55-68
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• 2018

Foliose species of the Bangiaceae (Porphyra s. l.) are very important in Korean fisheries, and their taxonomy and ecophysiology have received much attention because of the potential for developing or improving aquaculture techniques. Although 20 species of foliose Bangiales have been listed from the Korean coast, some of them remain uncertain and need further comparative morphological studies with molecular comparison. In this study, we confirm the distribution of four Pyropia species from the east coast of Korea, Pyropia kinositae, P. moriensis, P. onoi, and P. retorta sp. nov., based on morphology and rbcL sequence data. Although P. onoi was listed in North Korea in old floral works, its occurrence on the east coast of South Korea is first revealed in this study based on molecular data. P. kinositae and P. moriensis, which were originally described from Hokkaido, Japan, are first reported on the east coast of Korea in this study. Pyropia retorta sp. nov. and P. yezonesis share a similar thallus color and narrow spermatangial patches in the upper portion of the frond, and they have a sympatric distribution. However, P. retorta can be distinguished by the curled or twisted thalli and by molecular data. The biogeographic pattern of the two native species, P. kinositae and P. retorta, suggests that the east coast of Korea may have been a place of refugia during the Last Glacial Maximum (LGM), and then recolonized to the northern part of Japan through the restored East Korean Warm Current after the LGM.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1997년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 1997
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• pp.57-69
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• 1997

All of the Tsumami which affected severly the east coast of the Korean Peninsula in the years 1741-1993 are caused by earthquakes occurred along the boundary sea of Japan and norther Honshu. These earthquakes with magnitude greater than 7.0 are results of relative movement between the North American Plate and Urasian Plate. The active fault along the boundary of the two plates is attracted by many researchers since the 1983 May earthquake of magnitude 7.7. It is important to anticipate when the next large earthquake will occur and how much it affect the east coast of Korea. Among a few models of spatial seismic gap were proposed for earthquake occurrences accompanying Tsunami, Ishikawas' east-west seismic gap model is the most probable one. There is a tendency that the period between the activities of the active faults becomes shorter. It is expected that a large earthquake of magnitude 7.0 or above will occur along the eastern boundary of Japan Sea at the end of this century and produce Tsunami at the east coast of Korea.

• 생명과학회지
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• 제9권3호
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• pp.262-267
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• 1999

Mitochondrial DNA (mtDNA) polymorphism of the blue mussel (Mytilus edulis) species complex sampled from the east coast of Korean was studied using a partial sequence of COIII gene (336 bp). Samples obtained from three localities on the east coast of Korea revealed four haplotypes with two clearly differentiated mitochondrial clades (termed clades B and E), separated by 4.2% of minimum sequence divergence. This pattern indicates no difference between east and south coasts of Korea. According to population genetic theory on evolutionary characteristics of mtDNA, we concluded that mtDNA introgression from M. edulis to M. gallprovincialis might be a source for mtDNA polymorphism found in mussels on the east coast of Korea.

• 한국수산과학회지
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• 제11권2호
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• pp.49-54
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• 1978

한국 동해안해역에서 하계에 출현하는 냉수괴의 생성기구를 해양화학적인 측면에서 검토한 결과를 요약하면 다음과 같다. 1. 동해연안의 냉수괴출현해역의 인산염과 용존산계의 특수한 관계를 조사한 결과 동해남부 연안해역인 감포부근 해역에서만 용승현상을 인정할 수 있었으나 그 이북 동해중부해역에서는 용승현상을 인정할 수 없었다. 2. $\sigma_t-O_2$ diagram에 의해 동해연안해역의 구성수괴를 분석하면 T-S diagram 으로는 구별하기 어려운 북한한류계수와 일본해고유냉수를 구별할 수 있었다. 3. 동해남부 연안해역을 제외한 동해중부 연안해역에 출현하는 냉수괴의 기원은 일본해고유냉수의 용승에 의한 것이 아니고, 북한한류가 안안을 따라 남하하는 현상 때문으로 보인다.

• 한국지형학회지
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• 제20권3호
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• pp.27-39
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• 2013

본 논문은 남부 동해안의 5개 지역을 대상으로 최근 약 30년 동안 해안선의 장기적인 변화 경향을 파악하고, 중부 및 남부 동해안 연구를 종합하여, 동해안 해안선의 장기적인 변화 경향과 그 요인을 분석하였다. DSAS를 이용하여 해안선 변화량을 계산한 결과, 망양정 지역은 평균 28.9m, 조사 지역은 평균 6.4m 해안선이 후퇴하였고, 고래불 지역은 평균 25.0m, 대진 지역은 평균 10.6m, 봉길 지역은 평균 18.8m 해안선이 전진하였다. 동해안의 해안선 변화 경향을 종합하면, 1) 모든 지역 내에서 해안선은 전진과 후퇴 구역이 반복적으로 나타나고 있다. 2) 최근에 건설되거나 증축된 방파제와 접한 남쪽 구역에서는 해안선이 전진하였는데, 이는 북류하는 연안류의 영향으로 판단된다. 3) 해수욕장으로 이용되는 구역에서는 상대적으로 큰 해안선 후퇴 경향을 보인다. 4) 하천의 하구에서는 하천 상류 지역에서의 퇴적물 공급량 변화에 따라 해안선의 전진 및 후퇴가 다양하게 나타난다.

• 대한지리학회지
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• 제50권2호
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• pp.147-164
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• 2015

본 연구는 동해안의 8개 해빈을 대상으로 2012년 3월부터 2014년 2월까지 2년 동안 지형 측량을 실시하여, 해안선과 해빈의 계절적 변화 특성과 경향을 파악하였다. 동해안의 해안선은 계절적 변화량이 연간 변화량보다 크게 나타났고, 강원도와 경상북도 해안의 계절적 변화 양상에는 지역적인 차이가 다소 존재하였다. 동해안 8개 해빈의 계절적 변화를 종합하면, 여름철에는 해안선의 후퇴와 해빈의 침식이, 가을철에는 해안선의 전진과 해빈의 퇴적이 뚜렷하게 나타났다. 이러한 결과는 세계의 여러 중위도 해안의 계절적 변화 경향과는 다르지만, 우리나라 서해안 및 동해안의 선행 연구와는 대체로 일치한다. 여름철에 우세하게 발생하는 침식 현상은 태풍에 의한 폭풍파가 가장 큰 요인이며, 폭풍파에 의한 해안 침식은 늦겨울에도 잘 나타난다. 그리고 가을철에 우세한 해빈의 퇴적 현상은 여름철의 강한 침식 이후에 발생하는 해안 평형 작용의 결과로 판단된다.

• Fisheries and Aquatic Sciences
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• 제24권7호
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• pp.243-259
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• 2021

The spatial and temporal behaviors and fluctuations of the cold water that appeared in the South East Sea and the East Sea coast from 2016 to 2017 were investigated. The water temperature drop was large in the east coast from April to June and the southeast coast from July to September, and the temperature drop period was longer in the southeast coast. The water temperature fluctuated sensitively to the wind direction, and it gradually decreased in the southwest wind but rose as if jumping in the northeast wind. Wind stress and surface water temperature had an inverse correlation, which was larger in Bukhang-Idukseo, and decreased toward the north of Guryongpo. The cold water appeared mainly in Geojedo-Pohang after 1 to 2 days when the southwest wind was strong, but when the wind became weak, it shrank to the Idukseo (Ulgi-Gampo) and extended into the open sea in a tongue shape. Cold water was distributed only in Samcheok-Toseong in mid-May, Idukseo-Guryongpo and Hupo-Jukbyeon-Samcheok from late May to mid-July, and Bukhang-Idukseo in August-September. The intensity of cold water was greatest in mid-August, and the center of cold water descended from the east coast to the southeast coast from spring to summer. The water temperature fluctuation was dominant at the periods of 1 d and 7-21 d. In wavelet spectrum analysis of water temperature and wind, wind speed increase-water temperature decrease showed phase difference of 12 h in 2 d, 18 h in 3 d, 1.5 d in 4-8 d, and 2-3 d in 8-24 d period. The correlation between the two parameters was large in Geojedo and Namhang, Bukhang-Idukseo, Guryongpo-Jukbyeon, and Samcheok-Toseong. Monitoring stations with high correlation in all periods were generally parallel to the monsoon direction.

• 한국지형학회지
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• 제24권4호
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• pp.43-55
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• 2017

This study tries to examine papers on coastal terrace in the East Coast of South Korea and to summarize formative age and elevation of the terrace. Spatial and temporal variations of uplift rate in the Coast based on absolute age published are also reviewed. The terrace in the middle part in the Coast from Goseong to Samcheok distributes in an elevation of 10-20 m and its formative age is MIS 5a. The terraces during MIS 5e and 7 develop on an elevation of 20-35 m and 60-80 m, respectively. The mid-southern part in the Coast from Uljin to Yeongil Bay has the terraces with elevations of 10-25 m and 25-45 m and their ages are MIS 5a or 5c and 5e, respectively. The terraces with elevations of 10-25 m and 30-45 m correspond to MIS 5a and 5e, respectively, in the southern part in the Coast from Homigot to Busan. Assuming that elevation of sea level during the formation of each terrace is the same as in the present time, uplift rates in the Coast range from 0.05 to 1.36 m/ky with an average of approximately 0.33 m/ky. The highest and lowest rates since MIS 5 are found in the Gyeongju (approximately 0.39 m/ky) and Pohang (approximately 0.19 m/ky) areas. With a consideration of elevation of sea level at that time, however, the middle, midsouthern and southern parts in the Coast show uplift rates of 0.16-0.28 m/ky, 0.20-0.36 m/ky and 0.24- 0.36 m/ky since MIS 5, respectively, suggesting that the southern part in the Coast has experienced relatively higher uplift rate.