• Title/Summary/Keyword: ocean environmental

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Change of Coastal Ocean According to Kwang Yang Bay Development based on Landsat TM Images

  • Lee, Byung-Gul;Choo, Hyo-Sang;Lee, Gyu-Hyung
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.4 no.3
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    • pp.149-156
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    • 2000
  • This study presents an investigation of the changes that have occurred in the coastal ocean area of Kwangyang Bay located in the South Coastal region of Korea using remote sensing data based on Landsat Thematic Mapper (TM) multispectral digital data from 1988 and 1996. The coastal changes were detected using the digital histogram method and vector trace method. All the images were preprocessed, i.e. geometrically corrected, before the training set selection. when comparing the histograms of 7-band TM data, it was found that the band 5 image exhibited two critical Digital Number(DN) peaks, thereby indicating new coastal water and coastal land data. Based on this information, the coastal ocean area of the band 5 image was calculated using the vector tracing method supported by a CAD program. The result shows that the coastal ocean area decreased by about 5 % between 1988 to 1994. Accordingly, this gives a strong indication that the continuing land development will have a serious impact on the ecosystem of Kwangyang Bay.

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Screening of Differentially Expressed Genes in Diesel Oil-exposed Marine Fish Using DD-PCR

  • Woo, Seon-Ock;Yum, Seung-Shic;Yim, Un-Hyuk;Lee, Yaek-Kyun
    • Molecular & Cellular Toxicology
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    • v.2 no.4
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    • pp.251-256
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    • 2006
  • The exploration of genes which expressions are changed by exposure to ecotoxicants or pollutants can provide the important information about the reaction mechanisms in the body as well as adaptation to exterior stimulus or environmental changes. Also they can be developed as biomarkers for the detection of environmental pollution. Differential display polymerase chain reaction (DD-PCR) technique has been usefully used to hunt the clones which expressions are up-regulated or down-regulated by exterior changes and this study aimed to search for those clones in diesel oil-exposed rockfish (Sebastes schlegeli) using DD-PCR. The RNA isolated from liver of 20 ppb diesel oil-exposed rockfish was used for screening of the differentially displayed genes and total 44 differentially expressed genes (DEG) are detected then their nucleotide sequences were analyzed. The present data provided the general information about the effect of diesel oil contamination on marine organism and further more the primary step in development of new biomarkers for marine environmental pollution or ecotoxicological stresses.

Wave Responses of Buoyant Flap-typed Storm Surge Barriers - Numerical Simulation (부유 플랩형 고조방파제의 파랑응답 - 수치모의)

  • Jeong, Shin-Taek;Ko, Dong-Hui;Park, Woo-Sun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.2
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    • pp.196-208
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    • 2009
  • In this paper, wave responses of buoyant flap-typed storm surge barriers was studied numerically. Wave motions were modeled by using a linear potential wave theory, and behaviors of structures were represented as a Newton's 2nd law of motion. The near field region of the fluid was discretized as conventional quadratic iso-parametric elements, while the far field was modeled as infinite elements. Comparisons with the results from hydraulic model tests show that the present model gives good results. By using the model, the applicability of a buoyant flap-typed storm surge barrier in Masan bay was investigated considering field environmental conditions.

Contemporary organic contamination levels in digested sewage sludge from treatment plants in Korea: (2) Non-alkylated Polycyclic Aromatic Hydrocarbons (우리나라 하수 및 폐수 처리 슬러지의 다환방향족탄화수소의 함량)

  • Lee Kang-Young;Chung Chang-Soo;Kim Young-Il;Lee Hyun-Kyung;Hong Gi-Hoon
    • Journal of Environmental Science International
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    • v.14 no.4
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    • pp.413-425
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    • 2005
  • The 16 priority PAHs (Polycyclic Aromatic Hydrocarbons) designated by US Environmental Protection Agency were analyzed for some digested sludges from wastewater treatment plants in Korea. PAHs are an important group of organic contaminants present in sewage sludge due to their persistence and toxic potential. PAHs were extracted from freeze-dried sludges using a methylene chloride-methanol (2:1) mixture in a soxhlet extractor. The extracts were cleaned-up by silica gel/alumina combination column and subsequently fed into gas chromatograph/mass spectrometer (GC/MS) for determining PAH contents. The sum of the 16 PAHs in the sewage sludge varied from 534.8 to $5754.5 {\cal}ug/{\cal}kg$, dry wt.. In the sewage sludge, phenanthrene appears as the most abundant PAHs, followed by naphthalene, pyrene, fluoranthene. Source of the investigated sewage sludges relatively predominated pyrogenic. PAHs levels of sewage sludges in Korea appeared to be lower than those in other countries.

A study on the optimal equation of the continuous wave spectrum

  • Cho, Hong-Yeon;Kweon, Hyuck-Min;Jeong, Weon-Mu;Kim, Sang-Ik
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.7 no.6
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    • pp.1056-1063
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    • 2015
  • Waves can be expressed in terms of a spectrum; that is, the energy density distribution of a representative wave can be determined using statistical analysis. The JONSWAP, PM and BM spectra have been widely used for the specific target wave data set during storms. In this case, the extracted wave data are usually discontinuous and independent and cover a very short period of the total data-recording period. Previous studies on the continuous wave spectrum have focused on wave deformation in shallow water conditions and cannot be generalized for deep water conditions. In this study, the Generalized Extreme Value (GEV) function is proposed as a more-optimal function for the fitting of the continuous wave spectral shape based on long-term monitored point wave data in deep waters. The GEV function was found to be able to accurately reproduce the wave spectral shape, except for discontinuous waves of greater than 4 m in height.

A new free-living marine nematode species of the genus Belbolla (Enoplida, Enchelidiidae) from a subtidal zone of the East Sea, Korea, with some ecological and biogeographical information

  • Rho, Hyun Soo;Lee, Heegab;Lee, Hyo Jin;Min, Wongi
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.578-585
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    • 2020
  • A new free-living marine nematode species of the genus Belbolla Andrássy, 1973 belonging to the family Enchelidiidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Belbolla wonkimi sp. nov. differs from its congeners by the combination of the following characteristics: a relatively long body (3263-3396 ㎛), the absence of ocelli, nine oesophageal bulbs in the posterior pharynx, well-developed two winged precloacal supplements, longer spicule length(115-130㎛, 1.6-1.8 anal body diameter long), and a triangle-shaped shorter gubernacular apophysis (17-18 ㎛). Comparative tables on the biogeographical and morphological characteristics of Belbolla species are presented. A DIC (differential interference contrast) photomicrograph of the new species is also provided. This is the first taxonomic report on the genus Belbolla from Korean waters.

Characteristics and Multipurpose Utilization of Deep Ocean Water Resource (해양 심층수의 자원적 특성 및 다목적 이용)

  • 김현주;오병두;홍석원
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.05a
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    • pp.49-52
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    • 2001
  • The more the population grow, the severer the shortage of a basic human needs such as food, clean water, energy resources and so on. We had proved the possibility of utilizing deep ocean water as a environmental friendly resource to solve comprehensively above-mentioned problems for mankind based on observation and analysis of water quality. This study aims to evaluate feasibility of deep ocean water application, and establish multipurpose development and cascade utilization system of deep ocean water in the coastal zone of East sea to promote ocean development and fisheries industries.

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Diagnosis of Scoping and Type of Review on the Marine Environmental Impact Assessment for Ocean Energy Development Project (해양에너지개발사업 환경영향평가 검토유형 및 중점평가사항 진단)

  • Lee, Dae In;Kim, Gui Young;Tac, Dae Ho;Yi, Yong Min;Choi, Jin Hyu;Kim, Hye Jin;Lee, Ji Hye;Yoon, Sung Soon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.3
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    • pp.179-188
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    • 2015
  • This study reviewed the type of the project and developmental plan related to ocean energy development in the coastal land boundaries and the ocean, and suggested the efficient scoping method through the diagnosis of the key items of environmental impact assessment (EIA) in the coastal area. The major projects are the construction of tidal power plant, tidal current power plant, and offshore wind power plant in the public water, and also those are the construction of solar power plants in the coastal land boundaries. While the project plans on a large scale such as the construction of tidal power plant, it is important to consider both property of usefulness of the designated areas and harmony analysis with marine space availability based on the adequacy of the site selection and relevance of plan with the master plan for reclamation and strategic environmental assessment (SEA). And also it needs to be considered the careful checkup on the EIA checklist referring to the type of project, effective post-monitoring, and suggestion of mitigating methods to minimize the environmental impacts during the stage of actual environmental impact assessment. Introduction of a system of integrated marine environmental impact assessment should be considered for reasonable and effective manage to developmental projects on the marine spatial area.