• 한국수산과학회지
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• 제51권5호
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• pp.571-578
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• 2018

Seasonal variability in algal community structure of the subtidal zone was examined at four study sites on the southeastern coast of Korea from February to November 2016. A total of 81 species of algae (8 green, 12 brown, and 61 red) were indentified. During the study period, the greatest number of species was observed at Sinamri (57 species) followed by Daesongri (50 species), Dongbaekri (47 species) and Gangyangri (42 species). Of the six functional seaweed forms, the coarsely-branched form was the most dominant, accounting for about 43% of the total species at Daesongri. The annual average biomass in wet weight varied from $700.59g/m^2$ at Sinamri to $1,712.45g/m^2$ at Daesongri. The parameters of seaweed community structures were as follows: dominance index (DI), 0.30-0.54; richness index (R), 4.92-7.05; evenness index (J'), 0.54-0.72; and diversity index (H'), 2.05-2.91.

• 한국지형학회지
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• 제27권4호
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• pp.13-28
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• 2020

In this study, the distribution and topographic development of marine terraces, UHS (Upper Higher Surface) and HHS (High Higher Surface) at Yeondae-san area, Gampo-eup were discussed. We critically examined on the substance of the Yeongdong-myeon (a low-lying erosion surface) in the east coast of Korea. In study area, UHS including UHS-246m, UHS-241m, UHS-235m, UHS-220m, UHS-210m and UHS-220 is found on the highest altitude among the marine terraces in Korea. The existence of UHS requires new interpretation on topographical surface like Yeongdong-myeon, which has been commonly accepted as a theory in the society of Korean Geography. Since UHS is distributed continuously ascending on the altitude of HHS, the period of formation should be understood in the same context. And UHS of paleo-shoreline 246m has been estimated to be formed about 1.5 million years ago.

• 한국제4기학회지
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• 제17권2호
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• pp.15-15
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• 2003

In South Korea, marine terraces have been well developed along the eastern coastal zone, and previous researches on the marine terraces have also been focused on to this coastal zone. The marine terraces of the eastern coast of South Korea had been classified into three terrace groups, that is, the higher, middle, and lower surface ones, according to the heights of marine terraces by previous studies(Oh, 1981 ;Chang, 1987 ;Yoon et. al, 1999, 2003 ; Hwang and Yoon, 1996 etc.). Recently, however, it tends to classify the marine terraces based on the concept of geomorphic surface units(Lee, 1987 ; Kim, 1990 ; Choi, S. 2003; Choi S. et. al 2003a,b, etc). For example, it was proposed that the marine terrace surfaces of Eupcheon coast of the southeastern coastal area of Korea could be classified into 16 geomorphic surfaces, i.e., Eupcheon 1terrace(former shoreline height of 160m), 2(153m), 3(140m), 4(130m), 5(124m), 6(115m), 7(100m), 8(92m), 9(82m), 10(71m), 11(62m), 12(53m), 13(43m), 14(35m), 15(18m) and 16(10m) surfaces, in descending order, according to the former shoreline heights(Choi, S, 2003 ; Choi, S. et. al, 2003a,b). Among these terraces, Eupcheon 1, 2, 4, 5 and 7 surfaces had not been reported in previous works. Among the above mentioned marine terraces, Eupcheon 15 terrace, the most widely and continuously distributed marine terrace have been identified as marine terrace of the Last Interglacial culmination period(oxygen isotope stage 5e) which was based on amino acid dates(124∼125ka BP) and geomorphological features such as red soil, pollen analysis, fossil cryogenic structures and crossing terrace concept. Eupoheon 15 terrace surfaces have also been proposed as the key surface for the identification and correlation of the so-called '5e' marine terrace in the eastern coast of South Korea. This terrace was reconfirmed as the Last Interglacial culmination period, which was based on the identification of Ata tephra, one of the wide-spread marker tephra which indicates the Last Interglacial culmination period in Japan by Sasaki et. al(2002). It was thought that marine terraces of the eastern coast of South Korea had been formed by the steady-state uplifting during the Quaternary glacio-eustatic sea level changes(Choi, 1997). The uprift rate of 10cm/1,000years had been proposed in the eastern coast of South Korea based on the former shoreline altitude(18m) of the above Eupcheon 15 terrace. Therefore, it can be estimated that Eupcheon 1 terrace had been formed in the early Pleistocene from the above uprift rate. The OSL dating for the samples of Eupcheon 7, 9, 13, 15 and 16 terraces and identification of marker tephra in the terrace deposits are in progress. It is expected that more elaborate chronology on themarine terraces of the eastern coast of South Korea could be established by these absolute dates and marker-tephra.

• 해양환경안전학회지
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• 제18권5호
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• pp.379-387
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• 2012

동해 영덕 연안의 저염수를 보기 위하여 지난 2010년 격월별(2월 23일, 4월 6일, 6월 8일, 8월 19일, 10월 6일, 12월 20일)로 20개의 정점에서 CTD 관측을 수행하였다. 혼합층은 여름에 약 10 m 깊이로 얕았으며, 겨울에 약 20 m 깊이에서부터 저층까지 혼합층을 나타내었다. 연중 $5^{\circ}C$ 이하의 찬 물이 수온 약층 이심을 점하고 있었다. 염분 약층은 8월에는 깊이 20 m에, 10월에는 깊이 40 m에 분포하였으며 연중 가장 뚜렷하였다. 뚜렷한 저염수는 10월에 깊이 10 m에서 나타났는데, 10월에 강수량-증발량의 값이 음을 보였다, 이것은 10월에 영덕 연안에서 나타나는 저염수가 이류되어 온 것임을 시사하였다. 동해의 영덕 연안에서 나타나는 저염수는 동한 난류가 주요한 역할을 하는 것으로 보여진다.

• 한국해양학회지:바다
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• 제10권2호
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• pp.124-128
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• 2005

한국 주변해역의 해양시료에서 측정된 탄소동위원소 연대 값을 실제 역년(calendar age)값에 가깝게 변환하기 위하여 국립수산과학원(NFRDI)에서 제공한 핵실험 이전인 1942년에 한국 연안에서 채취한 2종의 연체동물 패각 시료를 이용하여 marine reservoir correction$({\Delta}R)$ 값을 측정하였다. 남서해안에서의 측정된 ${\Delta}R$ 값은 $-117\pm45\;^{14}C\;yr$, 남동해안에서 측정된 값은 $-160\pm35\;^{14}C\;yr$로 계산되었다. 이 값들은 황해의 중국연안에서 측정된 값들의 범위에 속하는데 이는 중국과 한국 연안해역에서 reservoir $^{14}C$ age가 지구규모의 해양 평균 reservoir $^{14}C$ age보다 적은 값을 갖고 있음을 말한다. 이들 지역의 낮은 ${\Delta}R$ 값은 아마도 담수유입의 영향을 반영하는 것으로 생각된다. 본 연구에서 제시된 ${\Delta}R$값은 한국 주변해역에서 측정된 탄소동위원소 연대 값을 실제 역년 값에 가깝게 변환시킬 수 있도록 도움을 줄 것이다.

• 한국지형학회지
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• 제26권4호
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• pp.81-96
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• 2019

The Yeongdeok 53m marine terrace (Y₅₃mT), Y₄₃mT, Y₃₃mT, Y₂₄mT, Y₁₉mT and Y₁₁mT distributed along the Yeongdeok coast, southeastern Korean Peninsula are well compared with the thalassostatic terraces of the high terrace 1 (ℓHT₁ ; 51m of the relative heights from the river floor), high terrace 2 (ℓHT₂ ; 43m), middle terrace 1 (ℓMT₁ ; 32m), middle terrace 2 (ℓMT₂ ; 25m), lower terrace 1 (ℓLT₁ ; 18m) and lower terrace 2 (ℓLT₂ ; 10m) respectively, developed along the lower reaches of the Chucksan-cheon and Obo-cheon rivers, judging from the comparison of paleosols (red soils) between the above marine and thalassostatic terraces. Using the Y₁₉mT of the MIS 5e as the key surface, we propose that the terraces of the Y₅₃mT and ℓHT₁, Y₄₃mT and ℓHT₂, T₃₃mT and ℓMT₁, Y₂₄mT and ℓMT₂, Y₁₉mT and ℓLT₁, and Y₁₁mT and ℓLT₂ have been formed at the MIS 11, 9, 7e and 7a (or 7a), 5e and 5a respectively. The red soils have been developed at the Y₁₉mT and ℓLT₁ and above them, but not on the Y₁₁mT and ℓLT₂ surfaces.

• 한국제4기학회지
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• 제18권2호통권23호
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• pp.75-86
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• 2004

The sea level curve and environmental change were reconstructed at Sejuk-ri during the early Neolitic Age, based on the sedimentary facies, the distribution of remains and carbon datings. Before 6,500 years BP, the sea-level experienced one oscillation. The Neolitic men utilized geomorphic environment which formed according to the sea-level change. They might be occupied in gathering, fishing and hunting including whales hunting. The Neolitic men made acom hollows in order to remove tannin. Besides, they remained shell mounds which were formed from 6,500 years BP to around 6,000 years BP. They left the living place about 6,000 years BP because of transgression.

• 한국환경과학회지
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• 제7권6호
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• pp.817-825
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• 1998

A three-dimensional ecosystem model is applied to the Suyoung Bay, located at the southeastern part of Korea, to study of the material distribution in the time scale of several tens days. The model has included of the DIN(Dissolved Inorganic Nitrogen), DIP(Dissolved Inorganic Phosphate), phytoplankton, zooplankton and detritus, and also was coupled with the physical processes. The spatial distribution of chlorophyll-a and primary productivity in the model is determined by the physical and chemical-biological parameters. The horizontal distributions of the DIN, DIP and chlorophyll-a are decreased from the coast to the off-shore, though the nutrients show some more complicated pattern than the chlorophyll-a. The nutrient contents in the off-shore are low, and thus a relatively low productivity(chlorophyll-a) are presented. On the whole, the distribution of the results of model are smoother than the observed ones and some small scale variation in the observed data cannot be reproduced by the model due to the resolution limits of model. However, the basic pattern and the quantitavities has been reproduced by the model well.

• Fisheries and Aquatic Sciences
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• 제16권4호
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• pp.325-329
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• 2013

New occurrences in Korean waters were recorded for two penaeid species: Atypopenaeus stenodactylus (Stimpson, 1860) and Metapenaeopsis toloensis Hall, 1962, which were previously known from the Indo-West Pacific up to southern Japan. The specimens were collected from the southeastern coast of Korea by a shrimp beam trawl. The former is the only known member of the genus Atypopenaeus and the latter is the sixth species of the genus Metapenaeopsis reported in Korea. Morphological descriptions and illustrations with color photographs of the specimens are given. At present, the Korean Penaeidae consist of 20 species in 11 genera. A key to the Korean genera of family Penaeidae is also presented.

• 한국항해학회지
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• 제21권4호
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• pp.39-47
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• 1997

We researched the mechanism on th flucturain of Bottom Cold Water in the western channel of Korea Strait, using 13 years(1981~1933) oceanographic data of FRDA. The bottom cold water in the western channel appears more often in summer and fall than in winter and spring, and its year-to-year variation of temperature is very large. Such variation seems to be closely related with the variations of cold waters in the subsurface layer of the southwestern East Sea. According to the longitudinal temperature distribution along the korean southeastern coast, a density difference occurs all the time at the still deepth between the western channel and the southwestern East Sea. Thus, it is inferred that the cold waters would intrude into the western channle form the subsurface layer in the southwestern East Sea as a density-driven current, and it intensity depends upon the density difference.