• 한국전자통신학회논문지
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• 제18권1호
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• pp.219-230
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• 2023

해양폐기물은 위치에 따라서 해안폐기물, 부유폐기물, 침적폐기물로 분류한다. 환경 문제에 대한 인식이 높아지면서 눈에 보이는 쓰레기들 외에 해양침적쓰레기에 대한 관리 및 수거가 필요하다. 우리나라 삼면의 바다 중 서해의 해양침적폐기물 종류별 분포 특성을 파악한 연구이다. 연구를 통해 폐합성수지, 고철, 폐타이어, 기타 순으로 많은 양이 나타난 것을 알 수 있었다. 특히, 서해 바다의 폐합성수지 심각성에 대해 보여주는 결과로 이로 인해 머지않아 해양생태계 뿐만 아니라 우리의 삶에도 막대한 영향을 미칠 것으로 보인다. 본 연구를 통하여 쉽게 알지 못하는 서해 침적쓰레기의 종류와 분포에 대해 인식하게 되고, 향후 수거활동에 도움이 되는 기초연구 자료로 활용될 수 있다.

• 한국해양환경ㆍ에너지학회지
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• 제13권4호
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• pp.335-340
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• 2010

황해 광역 해양생태계(YSLME) 프로젝트의 목적을 소개하고 구체적인 활동을 서술하였다. YSLME는 생산성이 높으나 가장 오염이 많이 되어 있는 곳이기도 하다. YSLME 프로젝트의 목적은 경계진단분석을 통해 파악된 환경문제의 피해를 전략 실행 프로그램(SAP)을 통해 줄이는데 있다. 생물다양성을 위협하는 가장 주요한 원인은 갯벌간척등을 통한 서식지 훼손이다. 1900년대 초 이래로 한국측 갯벌 40% 이상, 중국측 갯벌의 60% 이상이 훼손된 상태다. 남획과 오염등은 연안환경의 생물다양성 손실을 가져온다. 이 손실을 막기 위한 실행프로그램으로 정치가, 공무원, 과학자, 학생, 일반시민등 다양한 시민계층을 대상으로 환경의식을 고취시키는 켐페인을 벌여왔다. 또한 다른 시민환경단체와 연대하여 황해 파트너쉽을 구성하였다. 환경단체들은 국제기구 단체들과 달리 지역주민과 공고한 네트워크를 가지고 있기 때문에 지역의 환경보존노력을 위한 매우 중요한 파트너로 인식되고 있다. 소규모 지원프로젝트를 통해 환경단체들을 효과적으로 연계시킬 수 있었다. 세계야생동물기금 및 기타 연구기관과 공동연구를 통해 YSLME의 SAP를 수립하기 위한 생물다양성 평가 보고서를 발간하였다. SAP에서는 생물다양성을 위한 지역별 목표를 다음과 같이 설정하였다: 서식밀도 증대, 멸종위기종을 포함한 모든 생물종의 분포와 유전적 다양성 확보, 2007년 표준지침에 의거한 서식지 유지, 외래종 유입 위협의 감소. YSLME 프로젝트의 다음단계는 SAP를 승인하고 이를 성공적으로 이행함으로써 미래세대를 위한 생물다양성을 유지하는 것이다.

• 한국해양공학회지
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• 제26권1호
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• pp.78-83
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• 2012

The abundant nutrients contained in deep seawater are delivered by natural upwellings from the deep sea to the surface sea. However, the natural upwelling phenomenon is limited to specific areas of the sea; in other areas, the thermocline separates the surface sea from the lower layer. Thus, the surface layer is often deficient in nutritive salts, causing the deterioration of its primary productivity and ultimately leading to an imbalance in the marine ecosystem. Without a consistent supply of nitrogenous nutritive salts, they are absorbed by phytoplankton, resulting in a considerable problem in primary productivity. To solve this issue, a floating type of artificial upwelling system is suggested to artificially pump up, distribute, and diffuse deep seawater containing rich nutritive salts. The key technologies for developing such a floating artificial upwelling system are a floating offshore structure with a large diameter riser, self-supplying energy system, density current generating system, method for estimating the emission and absorption of CO2, and way to evaluate the primary production variation. Strengthening the primary production of the sea by supplying deep seawater to the sea surface will result in a sea environment with abundant fishery resources.

• 한국해양바이오학회지
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• 제3권1호
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• pp.1-6
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• 2008

Angola has a coastline of about 1,650 km long. Two diverging current namely, the Angola current with its warm water from the north and the cold Benguella Current in the south create a strong up-welling with a high productive ecosystem for marine resources. The area from Lobito to the mouth of the Cunene River, also known as the Southern fishing zone is by far the most productive of Angola's fishing zones. In 1977, the total potential of its marine fisheries sector was estimated at more than 700,000 tonnes per annum. In 2003, the Total Allowable Catch (TAC) established for demersal species was 57,600 tonnes and 160,000 tonnes for pelagic species. The most important resources are various marine demersal and pelagic fish including pilchard and the Cape and Cunene horse Mackerel (Tranchurus capensis and T. trecae). Sardinellas (Sardinella aurita and S. maderensis) are fished in parallel with horse mackerel. The rest of the catches are mainly demersal spp. and some deep water crustaceans. The demersal sppecies consist of Hake (Merluccius polli and M. capensis) and the large eye dentex spp. Tunas are caught at certain times of the year whilst some marine shrimp are also harvested from the Angolan waters. Angola also has several high value freshwater fish species, exploited by about 255 fishers. Tilapia sp. is among the most important and abundant fresh water fish found in Angola. Other species include the catfish (Clarias gariepinus) and fresh water prawns (Macrobrachuin rosenbergii). Some aquaculture ponds have been established in the country side, but due to lack of investment, proper training and the impact of civil war have seriously limited developments in the sub sector.

• 한국지역지리학회지
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• 제20권2호
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• pp.189-205
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• 2014

수많은 지자체들이 대규모 개발 사업이나 지역축제를 통해 관광객을 유치하고자 한다. 그러나 현실적으로 성공가능성이 낮으므로, 투입비용에 비해 효율이 높은 친환경 생태 관광산업에 더 신경을 써야한다. 서천 지역은 우수한 생태 및 문화자원을 보유하고 있었음에도 크게 주목받지 못하였지만, 국립생태원과 국립해양생물자원관이 새롭게 개원하면서 새로운 생태 관광의 중심지로 부상할 가능성이 높아졌다. 따라서 이 논문에서는 서천 일대에 분포하는 여러 생태 문화적 자산을 분석한 후 생태계서비스의 주요 기능인 생태관광을 도입하여 생태관광의 3요소인 자연환경, 탐방객, 지역민들이 모두 만족할 수 있는 프로그램을 개발하고자 하였다. 해안과 하안이 만나는 곳에 위치한 서천 지역에서는 기존의 유명 관광지와 연계하여 4개의 권역으로 생태자산을 재구성할 수 있었다. 탐방객들을 머무르게 할 방안으로 체험 활동을 통해 지역에서 숙박을 하도록 유도하였으며, 슬로우 라이프의 실현을 위해 각 경관들을 천천히 즐기도록 설계하였다. 생태연구의 메카가 될 국립생태원과 국립해양생물자원관을 중심으로 인근의 금강 하구 철새도래지와 람사르습지로 지정된 서천 갯벌 주변으로 탐방객들을 인도할 수 있도록 프로그램도 제시하였다. 본 연구를 통해 서천을 방문하는 탐방객들이 만족하고, 지역민들의 삶도 윤택해질 수 있는 계기가 될 것으로 기대한다.

• Ocean and Polar Research
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• 제31권2호
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• pp.219-229
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• 2009

In order to establish annual variations in the marine ecosystem of the East China Sea, suspended solids (SSs) and particulate organic carbon (POC) were extensively investigated in the northern part of the East China Sea from August 2003 to April 2008. Surface SS concentrations showed large spatial variations in spring and fall, but not in summer. Surface SS concentrations in spring were lower than those in summer and fall. In summer, SSs discharged from Changjiang were mostly deposited in the coastal areas and did not reach our study area which was located about 260 km from the river mouth. High SS concentrations were observed near the bottom, which resulted from resuspension of bottom sediments by the bottom currents. Surface POC concentrations did not exhibited large seasonal variations. Phytoplankton biomass was a main factor controlling surface POC concentrations. POC/chlorophyll ratios showed large seasonal variations, with maximum numbers in summer. POC/PON ratios were higher in summer than the Redefied ratio (6.6), while they were lower in spring and fall. In summer, higher POC/chlorophyll and POC/PON ratios were probably attributed to the high phytoplankton mortality caused by nutrient depletion in surface waters.

• Fisheries and Aquatic Sciences
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• 제13권2호
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• pp.167-181
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• 2010

To predict changes in the marine environment of the Beolgyo Stream Estuary in Jeonnam Province, South Korea, where cohesive tidal flats cover a broad area and a large bridge is under construction, this study conducted numerical simulations involving tidal flow and cohesive sediment transport. A wetting and drying (WAD) technique for tidal flats from the Princeton Ocean Model (POM) was applied to a large-scale-grid hydrodynamic module capable of evaluating the flow resistance of structures. Derivation of the eddy viscosity coefficient for wakes created by structures was accomplished through the explicit use of shear velocity and Chezy's average velocity. Furthermore, various field observations, including of tide, tidal flow, suspended sediment concentrations, bottom sediments, and water depth, were performed to verify the model and obtain input data for it. In particular, geologic parameters related to the evaluation of settling velocity and critical shear stresses for erosion and deposition were observed, and numerical tests for the representation of suspended sediment concentrations were performed to determine proper values for the empirical coefficients in the sediment transport module. According to the simulation results, the velocity variation was particularly prominent around the piers in the tidal channel. Erosion occurred mainly along the tidal channels near the piers, where bridge structures reduced the flow cross section, creating strong flow. In contrast, in the rear area of the structure, where the flow was relatively weak due to the formation of eddies, deposition and moderated erosion were predicted. In estuaries and coastal waters, changes in the flow environment caused by artificial structures can produce changes in the sedimentary environment, which in turn can affect the local marine ecosystem. The numerical model proposed in this study will enable systematic prediction of changes to flow and sedimentary environments caused by the construction of artificial structures.

• Fisheries and Aquatic Sciences
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• 제25권5호
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• pp.264-275
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• 2022

A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy^® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.

• Ocean and Polar Research
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• 제35권3호
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• pp.259-272
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• 2013

One of the factors influencing the climate around Korea is the oceanic-atmospheric variability in the tropical region between the eastern Indian and the western Pacific Oceans. Lack of knowledge about the air-sea interaction in the tropical Indo-Pacific region continues to make it problematic forecasting the ocean climate in the East Asia. The 'Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment (TIPEX)' is a program for monitoring the ocean circulation variability between Pacific and Indian Oceans and for improving the accuracy of future climate forecasting. The main goal of the TIPEX program is to quantify the climate and ocean circulation change between the Indian and the Pacific Oceans. The contents of the program are 1) to observe the mixing process of different water masses and water transport in the eastern Indian and the western Pacific, 2) to understand the large-scale oceanic-climatic variation including El Nino-Southern Oscillation (ENSO)/Warm Pool/Pacific Decadal Oscillation (PDO)/Indian Ocean Dipole (IOD), and 3) to monitor the biogeochemical processes, material flux, and biological changes due to the climate change. In order to effectively carry out the monitoring program, close international cooperation and the proper co-work sharing of tasks between China, Japan, Indonesia, and India as well as USA is required.

• Ocean and Polar Research
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• 제34권2호
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• pp.239-251
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• 2012

The food web dynamics in a coastal ecosystem of Korea were predicted with Ecosim, a trophic flow model, under various scenarios of primary productivity due to ocean warming and ocean acidification. Changes in primary productivity were obtained from an earth system model 2.1 under A1B scenario of IPCC $CO_2$ emission and replaced for forcing functions on the phytoplankton group during the period between 2020 and 2100. Impacts of ocean acidification on species were represented in the model for gastropoda, bivalvia, echinodermata, crustacean and cephalopoda groups with effect sizes of conservative, medium and large. The model results show that the total biomass of invertebrate and fish groups decreases 5%, 11~28% and 14~27%, respectively, depending on primary productivity, ocean acidification and combined effects. In particular, the blenny group shows zero biomass at 2080. The zooplankton group shows a sudden increase at the same time, and finally reaches twice the baseline at 2100. On the other hand, the ecosystem attributes of the mean trophic level of the ecosystem, Shannon's H and Kempton's Q indexes show a similar reduction pattern to biomass change, indicating that total biomass, biodiversity and evenness shrink dynamically by impacts of climate change. It is expected from the model results that, after obtaining more information on climate change impacts on the species level, this study will be helpful for further investigation of the food web dynamics in the open seas around Korea.