• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2014년도 춘계 종합학술대회 논문집
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• pp.411-412
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• 2014

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2009년도 춘계학술대회 논문집
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• pp.71-74
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• 2009

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 2009년도 발표 논문집 제18권
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• pp.208-211
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• 2009

• 한국해안·해양공학회논문집
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• 제29권3호
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• pp.154-161
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• 2017

본 연구에서는 침식성 파랑의 내습조건에 대해 인공리프의 길이(Lr), 개구폭(W), 개구부 수의 변화가 인공리프 주변 지형에 미치는 영향을 검토하고자 하였다. 구조물 주변에서의 표사이동 양상은 이동상실험을 통하여 검토하였으며 인공리프의 설치조건과 발생 유속 및 파랑변형, 지형변동과의 관계에 대해 고찰하였다. 실험결과 인공리프의 설치로 인하여 배후 침식량은 감소하였으나 개구부내에서의 세굴은 복수의 개구부를 갖는 구조에 비하여 단일 개구부를 갖는 조건에서 증가되었으며, Lr/W의 변화와 깊은 연관성을 보이는 것으로 확인되었다.

• 한국해양공학회지
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• 제30권3호
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• pp.186-193
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• 2016

Recently in Korea, a marine ranching project has continued to grow with the increasing needs of sea development. Management techniques, including settlement reduction and scour protection, have been required for constructing and maintaining the artificial reefs of this marine ranching project. The generation of settlement and scour can be influenced by ground characteristics. In this study, various laboratory tests (penetration test, two-dimensional water tank test) were performed to determine the settlement and scour characteristics of artificial reefs under various ground conditions. Three kinds of ground reinforcement were prepared: unreinforced, geogrid, and hybrid bamboo mat. Penetration test results showed that the normalized settlement ratio of ground reinforced with a hybrid bamboo mat was smaller than those of unreinforced ground and geogrid-reinforced ground. Two-dimensional water tank test results showed that the scour characteristics of ground reinforced with a geogrid were more reduced and stable than unreinforced ground. The amount of scour and ground settlement also decreased with increasing reinforced area.

• ALGAE
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• 제27권4호
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• pp.249-258
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• 2012

Nongeniculate coralline red algae are a common element of the Brazilian coastal zone, especially associated to coral reefs. During the course of ecological studies at Parque Municipal Marinho do Recife de Fora, two species of non-geniculate Corallinales were the major organisms covering the reef. Analyses of the vegetative and reproductive features of the species were analyzed; indicating that one new species of the genus Lithothamnion is proposed here based on the combination of several features associated with anatomy of the tetrasporangial conceptacles in relation to other species of the genus for which modern accounts are available. This new proposal along with other new species, new combinations and range extension of some species of the genus based in similar features clearly suggest that stability in species delimitation is possible. The second species found Pneophyllum conicum represents a range extension of more than 6,000 km from the Pacific in to the Atlantic Ocean suggesting that some nongeniculate species are widely distributed. The occurrence and abundance of these species supports and emphasizes the need for an extensive taxonomic reassessment of coralline red algae in the context of Brazilian coral reef biodiversity.

• ALGAE
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• 제28권3호
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• pp.281-288
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• 2013

Photosynthetic carbon fixation regulates air-sea $CO_2$ fluxes in the waters of coral reefs. However, little has been documented on the effects of solar UV radiation (UVR, 280-400 nm) upon photosynthetic behaviors of phytoplankton dwelling in these ecosystems. In order to evaluate the aforesaid, surface dwelling tropical coral reef phytoplankton assemblages collected from the South China Sea were exposed to solar radiation (i.e., photosynthetically active radiation [PAR] + UV radiation A [UVA] + UV radiation B [UVB], 280-700 nm; PAR + UVA, 320-700 nm; and PAR, 400-700 nm) under static or simulated-mixing conditions. Under the static condition, UVA and UVB significantly reduced the carbon fixation with the maximum of 22.4 and 15.3%, respectively; while lower UVR-related photosynthetic inhibition was observed in case of phytoplankton samples being subjected to mixing. At a moderate level of mixing (i.e., circulation time 80 min), the UVA and UVB caused inhibition were lowered by 52.1 and 79.6%, respectively. Based on this it could be stated that vertical mixing induced by winds and/or tides in the natural environments could reduce the inhibitory effect of solar UVR on phytoplankton productivity in the coral reefs water.

• Ocean and Polar Research
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• 제24권1호
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• pp.55-61
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• 2002

Eelgrass, Zostera marina L. widely spreads throughout all the coastal areas of the Korean Peninsula. However, some previously reported eelgrass populations disappeared. The disappearance was probably caused by anthropogenic disturbance such as reclamation and pollutant or exceeded nutrient release. Eelgrass beds occurred from the intertidal to the subtidal zone, mainly in lagoon, estuaries, ports, barrier reef and bays. Eelgrass beds were also found at the intertidal mud and sand flats, subtidal mud and sandbank in more exposed areas. Habitat characteristics of eelgrass beds distributed on the coasts of the Korean Peninsula varied among coast areas. Eelgrass distributed constantly throughout the southern coast of Korea, while the distribution was limited at lagoon, bay, port, or barrier reef on the eastern coast, because of steep water depth and high wave energy in that coast. On the western coast, eelgrass mainly appeared at the intertidal and subtidal zones in islands. Sediment characteristics of the Z. marina beds varied with locality, tidal current and water motion. Sediments of Z. marina beds were composed of sand, muddy sand, sandy mud and mud. Mean grain size ranged from 1.5 to 4.1 phi.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.1-7
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• 2000

Different substrata fixed as the roof (for shadow) on artificial iron reef had been developed as a tool for valuable fishery resources. The experiment was set up on a sandy bottom substratum at 8m depth in Muronohana, Ikata, Japan. Within one month of placement of the plates, diatoms dominated the experimental plates with a coverage of $100\%$ approximately. Enteromorpha intestinalis and Colpomenia sinuosa dominated within three months after the placement. E. intestinalis coverage on substrata was estimated $7\%$ on the plate shaped iron bar, $12-14\%$ on concrete plates, $18\%$ on the plate fixed pebble, $61\%$ on the plate to accumulated wood, and 80-100% on the steel materials plate. Whereas after four months of placement, C. sinuosa coverage on plates became $1-36\%$ on different plates, and $100\%$ on the plate to accumulated wood. The differences in E. intestinalis and C. sinuosa colonization on the different substrata were probably due to variations in their surface roughness influencing the settlement of zoospores, and thus gametophyte. development. After five months of placement, the above two species slowly disappeared.

• Journal of Ecology and Environment
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• 제38권2호
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• pp.271-279
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• 2015

After the reversion of Okinawa (Ryukyu Islands) to Japan in 1972, extensive urban and agricultural development resulted in a significant increase in sediment discharge to coastal waters. The release of sediment has caused the degradation of freshwater and coastal ecosystems and biodiversity. A consideration for catchment-to-reef continua, as well as agricultural (socioeconomic) factors is necessary to establish proper land-based management plans for the conservation of the island environment. We have set up a framework to integrate biophysics and socioeconomics: 1) setting a conservation target and threshold, 2) identifying the sources and processes, and 3) examining cost-effectiveness and management priorities. The framework may be applicable to other tropical and subtropical islands with similar characteristics.