• Ocean and Polar Research
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• 제33권2호
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• pp.99-111
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• 2011

To estimate the effects of limitation nutrients for phytoplankton growth and its influences on short-term variations of a winter phytoplankton community structure, we investigated the abiotic and biotic factors of surface and bottom waters at 20 stations of inner and offshore areas from 6 to 7 February in Gwangyang Bay, Korea. Also, several algal bio-assay studies were conducted to identify any additional nutrient effects on phytoplankton assemblage using surface water for the assay. The dominant species in the bay was diatom Skeletonema costatum, which occupied more than 70% of total species in most stations (St.1-16) of the inner bay. According to a cluster and multidimensional scaling (MDS) analysis based on phytoplankton community data from each station, the bay was divided into three groups. The first group included stations from the south-western parts of Myodo lsland, which can be characterized as a semien-closed eutrophic area with high phytoplankton abundance. The second group included most stations from the north-eastern part of Myodo lsland, influenced indirectly by surface water currents from offshore of the bay. The standing phytoplankton crops were lower than those of the first group. The other cluster was restricted to samples collected from offshore of the bay. In the bay, silicon (Si) and phosphorus (P) were not a major limiting factor for phytoplankton production. However, since the DIN: DIP and DSi: DIN ratios clearly demonstrated that there were potential stoichiometric N limitations, nitrogen (N) was considered as a limiting factor. Based on the algal bio-assay, in vivo fluorescence values in N (+) added experiments were higher compared to control and P added experiments. Our results suggested that nitrogen may act as one of the most important factors in controlling primary production during winter in Gwangyang Bay.

• 한국해양학회지
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• 제28권4호
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• pp.259-271
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• 1993

한반도 주변해역 대륙붕의 표층퇴적물 연구 결과 대륙붕 퇴적물은 크게 니질퇴적 상과 사질퇴적상으로 대표되는 전형적인 쌍빈도 입도특성을 나타낸다. 외대륙붕지역에 넓게 분포하는 사질 및 역질퇴적물은 지난 빙하기 해수면 하강 당시 집적된 잔류 퇴적 물로 해석되며, 내대륙붕 해저에 분포하는 세립한 지질퇴적물은 현재의 퇴적환경에서 공급, 운반, 집적된 현생퇴적물도 해석된다. 이들 세립물질은 강한조석전선 및 연안전 선에 의하여 외양쪽 확산이 크게 제한되며, 한반도 연안에 따라 서해로부터 남해를 거 쳐 동쪽방향으로 운반되는 것으로 해석된다. 그러나 동해의 우포분지에 분포하는 암회 색의 니질퇴적물은 잔류성 퇴적물로 여겨진다. 중간대륙붕 지역에는 현생의 세립물질 이 사립의 잔류퇴적물과 혼합된 혼합성퇴적물이 분포한다. 또한 잔류퇴적물의 일부는 현재의 해양환경조건에서 지속적으로 재동된 Palimpset 퇴적물로 해석된다.

• 한국항해항만학회지
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• 제28권5호
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• pp.359-364
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• 2004

해항선이 목적항에 접근하게 되면, 교통량은 증가하고, 특히, 항만입구에는 해상교통이 집중하면 항내 항로는 더욱 좁아진다. 따라서 기안에는 선박충돌을 방지하기 위한 특별한 항법규정이 필요하며, 우리나라에서는 개항질서법에 이들 규정을 두고 있다. 그러나 관련 항법규정이 서로 충돌하는 경우, 어느 것을 우선 적용하여야 하는가에 대한 문제와 그 규정의 정확한 의미를 규명할 필요가 있다. 왜냐하면 관련 항법의 해석과 적용에 대한 오해는 선박충돌의 원인이 되기 때문이다. 따라서 이 연구는 개항질서법상 항법 규정에 관하여 법해석학적으로 검토하고, 이를 통하여 올바른 항법적용에 관한 기준을 제시하고자 한다.

• 한국패류학회지
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• 제22권1호
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• pp.63-86
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• 2006

A list of species of bivalve mollusks, their local distributions and relative abundance in Yeongil Bay were analysed. Species richness ranging from 1 to 37 species was low (less than 10) in some stations at the entrance and in the central part of the bay. Fifteen species (Acila insignis, Nucula tenuis, Yoldia notabilis, Mytilus galloprovincialis, Arca boucardi, Axinopsida subquadrata, Felaniella usta, Mactra chinensis, Raeta pulchella, Nitidotellina hokkaidoensis, Theora fragilis, Alvenius ojianus, Callithaca adamsi, Ruditapes philippinarum and Laternula anatina) were most frequently encountered, and seven of them were most abundant numerically (per sample): Th. fragilis in the inner bay, A. insignis, N. tenuis, and A. ojianus in the outer bay, and C. adamsi, A. subquadrata, R. puichella in both parts. Local distributions of common species were described and presented in plotted data, and three distribution patterns were recognized. Biogeographical analysis shows that a majority of species (55%) belongs to the subtropical group, tropical-subtropical species (16%) play a relatively significant role, and the percentage of boreal (temperate) and boreal-arctic species is 18% which characterizes the whole fauna as subtropical. Zonal-biogeographical composition and number of species in families in Yeongil Bay are compared with those of some Japanese (Wakasa and Mutsu) and Russian (Peter the Great, Possjet and Amursky) bays of the East Sea. The absence of a number of typical warm-water embaymental mollusks in Yeongil Bay found in the north further East Sea and Japan, and the similar zonal-biogeographical structure of the inner and outer bay faunas are explained by active water exchange due to the openness of the bay, relatively low summer temperatures, and presence of upwelled cold waters.

• 한국해안·해양공학회논문집
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• 제29권5호
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• pp.247-259
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• 2017

입자추적기법(Lagrangian Particle Tracking; LPT)을 적용한 수치모델을 이용하여 조력발전소 운영에 의한 시화호 외측해역에서의 체류시간 변화를 파악하였다. 수치모델의 실험안은 공간적인 분포 특징을 살펴보기 위하여 시화호 외측 해역을 4개 구역으로 나누어 구역별 평균체류시간을 산정하였다. 구역별 평균체류시간은 운영 전과 운영 중 모두 가장 외해에 위치한 지역(약 3일)에서 내만에 위치한 지역(약 13일)으로 진입할수록 증가하는 특징이 나타났다. 구역별 평균체류시간 변화를 운영 전과 운영 중으로 비교하면 운영 전에 비해 운영 중에 가장 외해에 위치한 지역에서는 증가하고 나머지 구역에서는 감소하였다. 조력발전소 운영에 의한 인위적인 배수는 가장 외해에 위치한 지역에서 와동(vortex) 형성으로 입자 정체를 유발하였고, 나머지 지역에서는 연행작용(entrainment)을 발생시켜 체류시간의 변화에 영향을 주었다. 즉, 배수 시 발생하는 제트류(jet flow)와 와동, 연행작용으로 인한 체류시간 변화는 외해와 내만의 수평적 혼합 증가를 보여준다.

• 해양환경안전학회지
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• 제18권2호
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• pp.85-93
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• 2012

HS-SPME법을 이용하여 한국 서남해 연안해역에서 Sea-nine 211, Irgarol 1051, Diuron과 같은 방오제의 분포 특성을 검토하였다. 반감기가 짧은 Sea-nine 211은 모든 시료채취지점 및 지역의 해수와 퇴적물에서 아주 낮은 농도 또는 검출한계 이하로 분포하였다. Irgarol 1051은 해수 및 퇴적물에서의 최고 농도가 각각 $6.98{\mu}g/L$, 28.50 ng/g-dry wt로 검출되었으며, 지역별 분포 특성은 나타나지 않았다. 반감기가 가장 길고 생물 농축성이 강한 Diuron은 모든 시료채취 지점에서 Sea-nine 211과 Irgarol 1051보다 높은 농도로 분포하였으며, Mo7(목포)의 퇴적물에서 최고농도(3882.22 ng/g-dry wt)로 분석되었다. Irgarol 1051과 Diuron은 조선산업단지 및 선박정박지가 위치하고 있는 지점에서 높은 농도로 분포하는 것으로 나타났다. 또한 퇴적물에서의 방오제 분포는 내만에서 외만으로 그 농도가 낮아졌다. 이러한 결과로부터 방오제는 내만에 위치하고 있는 항구나 조선산업단지로부터 오염될 가능성이 높을 것으로 판단된다.

• 한국수산과학회지
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• 제37권6호
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• pp.469-477
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• 2004

This study examined distributional patterns of Asterias amurensis in Tongyeong, the central South Sea of Korea. The density of the sea star was estimated at 10 chosen sites in the inner and the outer parts of the Tongyeong coast from December 2000. The mean density of the species in this area was $2.4ind./m^{2}$. The seasonal surveys conducted at 3 arbitrary chosen sites (i.e., sea cage, reef and soft sediment) also showed that the abundance of the species at the sea cage site $(density:\;3.6\;ind./m^{2};\;biomass:\;250.7\;gwwt/m^{2})$ was significantly higher than at the reef site $(density:\;1.7\;ind./m^{2};\;biomass:\;63.5\;gwwt/m^{2})$ and the soft sediment site $(density:\;0.4\;ind./m^{2};\;biomass:\;18.9\;gwwt/m^{2})$. Densities were higher at sea cages areas than at reefs and soft bottom sites. At sea cage site, A. amurensis population exhibited a strong aggregated distributional pattern. In contrast, at reef and soft bottom sites, A. amurensis population showed a random distributional pattern. The spatial difference in prey species and its abundance was the primary factor determining the spatial heterogeneity of the sea star in its behavior characteristics. Experiments on the feeding preference indicated that A. amurensis had a strong selectivity on its prey, but this selectivity varied between populations living in different sites. In particular, A. amurensis populations at the reef site showed a strong selectivity on various sessile and mobile animals living in reef areas, suggesting that these animal groups may play a role as "windows for the survival of A. amurensis". These results suggest that the distribution of A. amurensis in Tongyeong is closely associated with abundance of prey species and the bottom composition.

• 한국수산과학회지
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• 제43권6호
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• pp.665-669
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• 2010

To confirm the distributon of finless porpoise, Neophocaena phocaenoides, in the South Sea of Korea, data on bycatch, stranding, and drifting of finless porpoises from 1999 to 2009 were used and a sighting survey was conducted from the R/V Tamgu No. 9 and 10 in June and November, 2009 and March, 2010. The total number of bycaught, stranded, and drifting finless porpoises was 607, with position being known for 186 of these. At the center of Yeosu, there were few position data on bycaught, stranded, and drifting finless porpoises, and data could not confirm the distribution of finless porpoises. Thus, there were limits on the usefulness of bycaught, stranded, and drifting data for confirming the distribution of finless porpoises. In the three sighting surveys, the sighting rate was highest at 0.231 ind./n.m. in the western South Sea in June, 2009. Sighting rate was less than 0.1 ind./n.m. in November, 2009 and March, 2010. This is likely to be due to seasonal migration in western South Sea. All sighting rates in the eastern South Sea were over 0.13 ind./n.m.. According to the results of the sighting survey, finless porpoises are distributed around the islands and inner bay along the path of the research vessel in the South Sea. There were numerous finless porpoises in the offshore areas of Mokpo, Yeosu, Tongyeong, Dadaepo, and Gaduk-do. This study will be utilized as part of a future abundance assessment of finless porpoise in the South Sea of Korea.

• 대한지리학회지
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• 제35권1호
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• pp.17-38
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• 2000

The marine terraces often offer come important clues to understand the topographic development during the Quaternary and the present landforms in korea. We examined the mechanism of the marine terraces formation along the coast from Samjung-Ri(community), Guryongpo-Eup(county) to Haseo-Ri, Yangnam-Myun(county), Gyungju-Si(city). Among the various but unique factors of the given coastal environment, which should contribute to the marine terraces formation together, we focused on five possible factors for the present stydy. Geologic difference in bedrocks, protrusion degree of coastiline, topological relief of sea-bottom, fluvial characteristics on land, and pattern of the waves appeared to act cooperatibely on the terrace formation of Southeastem coast in korea, while the fluvial characteristics seemed play a significant but localized role in it. Wide distribution of middle surfaces on the coast of Samjungri-Janggilri could be due to the concentration of the high waves and the weakness of the Tertiary volcanic rocks. For the sporadic distribution of the terraces on the coast of Gupungri-Gyewonri, it seemed attributable to the erosion -susceptible weak bedrock, the coastline of inner bay, shallow sea-bottom with the gentle relief, and other fluvial characteristics with the low divides. Together with the geologic difference in bedrock, other factors including protrusion degree of coast, topological relief of sea-bottom, and the transportation loads by the stream Daejongchon are believed to act cooperatively on the mechanism of the marine terraces formation on the coast of Duwonri-Upchonri.

• 한국해안·해양공학회논문집
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• 제25권4호
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• pp.219-235
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• 2013

시화조력발전소 가동에 따른 인근 해역의 해수특성 및 성층변화를 파악하기 위하여 3차원 수치모델을 이용하였다. 여름철의 경우, 하천을 통해 유입되는 담수의 영향으로 인해 시화호 내측의 밀도는 수온보다는 염분에 의해 더 영향을 받는다. 조력발전소 가동 전에 호 내측에서는 외해에 비해 상대적으로 고온, 저염의 해수특성을 보이는 반면에 조력발전소 가동 시에는 호 내측의 수온이 소폭 낮아지고 염분이 증가하는 경향을 보인다. 또한 조력발전소 가동 시 해수의 유입 유출이 활발해짐에 따라 혼합효과의 증대로 인해 시화호의 밀도는 증가하고 성층은 약화되는 것으로 나타났다.