• Fisheries and Aquatic Sciences
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• 제21권4호
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• pp.9.1-9.7
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• 2018

To establish a comprehensive management strategy, as part of the optimization of cultural practice for an oyster rack culture system, we used a numerical model to estimate the primary production in the waters on the eastern coast of Wando island, South Korea. The estimated primary production ranged from 17.12 to $1052.55mgC\;m^{-2}day^{-1}$ ($204.22{\pm}224.75mgC\;m^{-2}day^{-1}$ in average). Except for the times of peak phytoplankton blooms, the estimated primary production (PP) was consistently under $200mgC\;m^{-2}day^{-1}$, which is more similar to the value of PP measured off the western coast of South Korea than the southern coast. No clear relationship was observed between nitrogen content and rainfall with the exception of heavy rainfall events, indicating that precipitation might not be the main source of nutrients in these waters. No clear influence was observed from Doam tidal discharge, located 24 km north from these waters due to main tide comes in this area from the channel between Gunwe-myeon in Wando island and Pukpyeong-myeon in Haenam-gun. Because of the shallow water depth and strong tidal current, resuspension of sediments, which causes an input of nitrogen into the system, could be easily caused by even mild wind and the infrequent passing of ships. Microscopic examination of the phytoplankton composition showed additional contribution of benthic species such as Paralia sulcata into the waters, which increase the productivity of oyster farms in the waters. The availability of nitrate and phosphate for primary production was temporarily limited throughout most of the spring and autumn blooming season.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.573-576
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• 2008

해양 환경하의 조건에서 건설된 콘크리트 구조물이 해수에 직접 닿을 경우, 해수중의 염화물 농도를 측정함으로서 콘크리트 구조물의 염화물 확산계수 산정이 용이하지만, 해수와 직접 접촉되지 않는 경우, 비래염분 등에 의한 염화물 확산계수의 산정에 어려움이 있다. 따라서, 해안에 인접한 콘크리트 구조물에 날아드는 염분량 등을 측정 평가하는 것은 콘크리트 구조물의 설계 시공 및 유지관리에 중요한 기초자료로 활용될 수 있다. 따라서, 본 연구에서는 동해, 서해, 남해안의 27개 지역, 72개 지점을 선정하여 매월 1회 1개월간의 누적 비래염분량을 '03년 7월부터 '06년 6월까지 3년간 측정하여 국내 해안가의 비래염분 환경을 계절별 비래염분량의 측면에서 알아보고자 하였다. 측정 결과, 동해와 남해안에서는 여름철, 서해안에서는 겨울철에 상대적으로 많은 비래염분량이 발생하였으며, 이것은 계절풍에 기인한 것으로 판단된다.

• 대한지리학회지
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• 제39권6호
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• pp.863-872
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• 2004

서해안으로 유입하는 소규모의 하천은 충적지가 분포하는 구간에서는 거의 전역에 걸쳐서 조류의 작용을 강하게 받고 있다. 전라남도 영광군의 해안으로 유입하는 불갑천도 예외가 아니다. 불갑천 하류의 주요 지형은 충적지와 해안사구, 그리고 간석지이다. 이곳의 충적지는 간석지 퇴적물 위에 불갑천이 운반한 토사가 쌓여서 형성되었다. 충적지의 구성물질은 하천이 유역분지에서 운반하는 조립질의 풍화산물보다 창조류가 외해로부터 운반하는 미립물질의 비율이 해발고도가 낮을수록 증가한다. 불갑천 하류의 임해충적평야는 1920년대 후반부터 근대적인 수리시설이 도입되면서 본격적으로 개발되었다. 평야의 면적은 20세기 이후 계속 확대되었다. 불갑천 하구의 간석지가 방조제 건설과 함께 간척되어 해안선이 상당히 전진하였기 때문이다. 그 결과 해안사구가 농경지 사이에 갇혀버리고 말았다. 해안사구에는 대규모 사구취락이 형성되어 있으며 대부분 논과 밭으로 개간되었다. 사구의 보존상태가 양호한 곳에서만 곰솔이 자란다. 불갑천 하류에서는 밀려오는 뻘에 의해 퇴적층이 확대되어 왔으며 해안사구는 모래공급을 받지 못한 채 파괴되고 있다. 즉, 뻘은 쌓이고 모래는 깎이고 있다. 본 연구의 목적은 서해로 유입하는, 규모가 작은 하천의 하류부를 중심으로 퇴적층이 발달한 전라남도 영광군을 사례로 임해충적평야의 수리체계를 파악하는 것이다. 수리체계 의 파악이 충적지형을 이해하는 하나의 방법일 수 있기 때문이다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 춘계학술대회 논문집
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• pp.99-104
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• 2003

This study investigated the yearly variation of pollutant loads outflowing from six watershed of Yeong-il Bay and compared the relationship of pollutant load and water quality, and estimated the Inner productivity of Yeong-Il Bay by using ${\Delta}COD$ method which analysis nonlinear process of water quality. As the estimated results for the pollutant loads of Yeong-Il Bay, total COD load outflowing from Hyeong-san river in flood season(summer) of 2001 year was 2275.0 kg/hr and in dry(low water) season(winter) 852.8 kg/hr, respectively. Load quantity in flood season was about 2.67 times than that in dry season. And as the calculated results of the net-flux of water for seven divisions, it showed that the net-flux of water increased for the divisions of the north coast and inner sea of Yeong-Il Bay but decreased for the south coast. On the contrary, for the cases which water quantity increase from land, the net-flux of water in estuary front of Hyeong-san river decreased but outflowing quantity of that though division of the south coast of Homi-got increased. Finally, this study compared the Inner productions for flood and dry season of Yeong-il Bay by using ${\Delta}COD$ method.

• 한국정보통신학회논문지
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• 제8권4호
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• pp.938-945
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• 2004

남해 중부해역에서 적조발생과 관련해서 적조 다발월인 여름과 초가을에 기온과 마찬가지로 높은 수온을 유지한다. 또한 많은 강수량에 의하여 부유물질 및 영양염류가 증가하고 염분이 대체로 떨어지는 것을 알 수 있었다. 이때 적조의 bloom으로 인하여 대표적인 영양염류인 질소와 인의 값이 떨어진다. 그리고 적조생물의 사후 미생물 분해 작용이 활발하여 산소의 소모가 증가하여 용존산소가 급격히 떨어지고 화학적산소요구량이 높게 나타나는 것을 알 수 있었다. 이때 식물성플랑크톤의 성장 제한인자로 작용하는 부유물질, 인산염, 질산염의 공간분포도를 이용해서 적조발생의 잠재력을 지닌 최적지를 결정하였는데, 최적지로서는 여수∼돌산해역, 가막만 북부지역, 남해 일부해역, 나로도해역, 고흥 남부의 일부 연안, 득량만과 인접한 고흥 서부 해역이었다.

• Journal of the korean society of oceanography
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• 제38권2호
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• pp.68-79
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• 2003

Although seagrasses are relatively abundant, few studies have been conducted on seagrass physiology and ecology in Korea. Zostera marina is the most abundant seagrass species, widely distributed throughout all coastal areas of the Korean peninsula. To examine seasonal dynamics and spatial variations of eelgrass, Zostera marina distributed on the coast of Korea, morphological characteristics, biomass, tissue nutrient constituents, leaf productivity and environmental factors were monitored monthly from the eelgrass beds in Kabae Bay and Kosung Bay on the south coast of the Korean peninsula from June 2001 to June 2002. Eelgrass density, biomass, morphological characteristics, leaf productivities, and tissue nutrient constituents exhibited clear seasonal variations, and these seasonal trends reflected seasonal changes in water temperature. Eelgrass shoot density and biomass at Kabae Bay site showed more obvious seasonal trends than Kosung Bay. No strong seasonality in Kosung Bay site appeared to be caused by high water temperature ($>30{\circ}C$) during summer months at this site. Despite differences in nutrient availabilities between two study sites, eelgrass biomass and leaf productivities were not significantly different between study sites, and this lack of spatial variations implies that the ambient nutrient availabilities at the present study sites are in excess of seagrass nutrient demand. Eelgrass tissue N content and sediment pore water DIN concentrations exhibited reverse relationship at the present study. This reverse relationship suggests in situ nutrient concentrations are not good indicator of nutrient availabilities, and regeneration and turnover rates of sediment nutrients are also important factors to determine nutrient availabilities at the site.

• 한국해양학회지:바다
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• 제24권3호
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• pp.429-435
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• 2019

연안에서 해표면고도를 정확하게 측정하도록 특별히 설계된 SARAL/Altika위성에 의해 관측된 해류를 비교 검정하기 위해 2015년 3월부터 2년간 위성추적 뜰개가 동해 북부 해상에 투하되었다. 해표면 고도 측정 위치에서 반경 20 km 이내에 위치한 뜰개(30분 간격으로 GPS로 위치 관측)와 비교한 결과, 수심 200 m 보다 얕은 해역에서 외해와 유사하게 높은 상관관계를 가진 것으로 나타나, 해류의 직접 관측이 어려운 동해 북부의 연안류의 시간 변동을 관측할 수 있게 되었다. 리만 해류는 일년 년중 시베리아 연안을 따라 남하하는 해류로 관측되었으며, 북한 한류는 여름철에만 남향하는 해류를 보였다. 북한 한류는 무수단곶 이남에서는 주로 남향류를, 무수단곶 이북에서는 무수단곶 근해에서의 에디 존재 유무에 의해 방향이 결정되는 것으로 연구되었다.

• ALGAE
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• 제34권3호
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• pp.217-228
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• 2019

The marine brown algal genus Colpomenia has a worldwide distribution, with five species reported in Korea and Japan. However, no studies to date attempted to identify the number of species and geographical distribution of Colpomenia along Chinese coast. To fill the biodiversity knowledge gap, we analyzed 63 mitochondrial cox3 and 62 mitochondrial atp6 sequences of Colpomenia specimens collected from 30 localities along the Chinese coast. Maximum likelihood and Bayesian inference trees suggest the presence of at least three Colpomenia species (i.e., C. peregrina, C. claytoniae, and C. sinuosa) in China. C. peregrina and C. claytoniae are documented for the first time. C. sinuosa was only found in the South China Sea and its distribution didn't overlap with that of C. peregrina which was found in the Yellow-Bohai Sea and the East China Sea. C. claytoniae appears to be confined to three isolated islands in the East and the South China Sea, where it occurs in sympatry with, respectively, C. peregrina and C. sinuosa. Future study can focus on comparing eco-physiological differences of Colpomenia species in response to environmental variables and exploring possible genetic hybridization / introgression at inter-specific contact zones.

• 한국해양바이오학회지
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• 제14권2호
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• pp.102-111
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• 2022

Beakryoung-do is located in the north along the western coast of South Korea. Owing to its geographical limitations, not many studies have been conducted on marine algae in this region. This study aims to investigate the marine algal flora and the community structure in the intertidal and subtidal zones of Nampo-ri, Beakryoung-myeon, Ongin-gun, Incheon regions of South Korea. The study was conducted from August 2015 to June 2016 during all seasons. A total of 95 algal species, including 7 green algae, 12 brown algae, and 76 red algae were collected and identified; 52 algal species were found in the intertidal zone and 83 in the subtidal zone. The vertical distribution of algae from upper to lower intertidal zone was Neorhodomela aculeata - Caulacanthus okamurae, Gelidiophycus freshwateri - Neorhodomela aculeata, Caulacanthus okamurae - Sargassum thunbergii, Caulacanthus okamurae. Findings indicated that Sargassum thunbergii and Neorhodomela aculeata were the biomass-dominant species in the intertidal zone and Corallina officinalis and Undaria pinnatifida were biomass-dominant in the subtidal zone. Average values of marine algae biomass in the intertidal and subtidal zones were 252.6 g wet weight m^-2 and 291.9 g wet weight m^-2, respectively. Further, 38 new species were found in Beakryoung-do, with 25 of them specifically found in the subtidal zone. More studies on marine algal flora in the subtidal zone are needed to understand the changes in marine flora along the western coast.

• 한국지형학회지
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• 제26권4호
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• pp.67-79
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• 2019

This study documents the level of paleo-shoreline and the timing of formation of the lowest marine terrace (1st terrace) distributed in Dadaepo, Busan, South Korea. In the study area, the elevation of paleo-shoreline of the 1st terrace is clearly identified as 5 meters above mean high tide based on the elevation of wave-cut platforms and the elevation of boundary between marine and terrestial sediments. This is well consistent with the fact that are found along the Southern coast of the Korean Peninsula including Daepo-dong, Sacheon-si. The timing of formation of the 1st terrace in Dadaepo is confirmed to have been deposited around 70,000~80,000 years BP (MIS 5a) according to OSL and IRSL dating ages. However, because the formation age of the 1st terrace in Sacheon-si Daepo-dong (Southerm coast) and Pohang-si Umok-ri (Eastern coast) previously identified as about 90,000~100,000 years BP (MIS 5c), further discussion of what is needed. Possibly, it can be interpreted that the sub-interglacial (MIS 5a and 5c) sea-level records during the last interglacial period are likely to be selective on land depending on regions.