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동중국해 북부해역 수온, 염분의 분포 변동 특성

  • Jang, Lee-Hyeon;Kim, Sang-U;Go, U-Jin;Geleekko, Yamada;Seo, Yeong-Sang
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2007.05a
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    • pp.331-335
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    • 2007
  • 본 연구에서는 장기간의 현장관측 수온, 염분자료를 분석하여 동중국해 북부해역에서 계절별 수온, 염분의 변동 특성을 조사하였다. 표층의 경우 춘계 수온상승에는 공간적인 차이가 있다. 또한 서부해역($125^{\circ}E$ 이서)에서는 32 psu 이하의 저염 분포가 나타나고 제주 남서해역에서 33psu 이하의 저염수가 춘계부터 제주 주변해역으로 확장한다. 하계 표층염분은 $28.0{\sim}32.4$ psu로 연중 최저값은 보이며, 전해역 표층 염분이 33psu 이하로 저염의 양자강 희석수가 하계에 동중국해 북부해역 표층 전체에 영향을 미치고 있다. 추계의 표층수온과 염분은 동고서저형의 수평분포를 나타낸다. 수온 하강은 서부해역인 대륙 연안수역이 동부의 대마난류수역에 비해 크고, 서부해역에서 33psu 이하의 설상형 저염분포가 이시기에 남동쪽으로 관입되는 형태로 나타나 동계의 남북방향의 염분전선과 이어지게 된다. 연직해황의 경우 동계 수온과 염분은 활발한 대륙작용에 의해 전수층에서 균일한 분포를 나타내며, 대륙연안수역에서는 저온, 저염($12^{\circ}C$, 33psu 이하)의 분포를, 대마난류수역에서는 고온, 고염($16^{\circ}C$, 34.4psu 이상)분포의 지역적인 특성으로 구별된다. 춘계에는 수온약층이 형성되며, 저층에는 동계에 형성되어 대륙연안수와 외양수 사이에 고립된 $13^{\circ}C$ 이하의 냉수괴가 분포한다. 염분은 표층 저염화가 시작된다. 하계에는 양자강 유출수의 영향으로 전해역 표층에서는 30psu 이하로 전해역에서 저염화 양상이 나타나며, 표층에서 30m 층까지 매우 강한 염분약층이 형성된다. 추계 수온 엽문은 균일한 연직수온분포가 나타나며, 동부해역에서는 수심 $75{\sim}100m$사이에서 수온, 염분약층이 형성된다. 동중국해의 수괴는 뚜렷한 계절 변동을 보이며, 대마난류수역인 동부해역에서는 수괴 계절변동의 요인으로 계절 수온변동이 지배적이고, 수온변동은 춘계와 하계 사이에 가장 크다. 중앙부와 대륙연안역인 서부해역에서는 수괴 계절변동에 수온외에 염분 변화가 주요한 요인으로 작용하며, 염분은 하계와 추계 사이에 가장 변동이 크게 나타난다. 즉, 동중국해의 수괴변동에는 변동요인에 따른 공간적인 차이가 있으며, 수괴변화 특성으로 동중국해는 수온변화가 수괴변동에 직접요인이 되는 동부 대마난류수역과 염분변화가 수괴변동의 직접요인인 서부의 대륙연안수역으로 구분된다.

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Evaluation of the Navigational Safety Level in Korean Coastal Waterway from the Viewpoint of Ship Operator′s Stress (조선자의 조선부담감을 고려한 연안해역의 항행 안전성 평가에 관한 연구)

  • 금종수;장운재
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.9 no.1
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    • pp.65-72
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    • 2003
  • The prevention of marine accidents has been a major topic in marine society and various policies and countermeasures have been developed, applied to the industries. In order to improve the navigational safety level in the coastal waterways, the navigational safety level must be evaluated from the mariner's perception of safety. So far as human beings are concerned, there are many types of fuzziness in the evaluation of navigational safety level. In order to reflect these fuzziness on this evaluation, this paper introduces the fuzzy integral suggested by Choquet to represent the fuzziness in the evaluation process. This paper aims to develop the method for this evaluation from the viewpoint of mariner's operational stress using the fuzzy measure and Choquet integral. In this paper, Korean coastal area is divided into 8 sectors and evaluated the priority for the needs of coastal VTS and navigational aids. The results are found in the order named Mokpo, Yosu, Pohang, Inchon, Busan, Geoje, Gunsan, Donghae coastal area.

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Observation and Record of Sea Turtles in Bycatch and Stranding from Jeju Island of Korea (우리나라 제주도에서 관찰된 바다거북의 좌초와 혼획)

  • Jung, Min-Min;Moon, Dae-Yeon;Kim, Seong-Ho;Kim, Heung-Soo;Kim, Jae-Woo
    • Journal of Fisheries and Marine Sciences Education
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    • v.24 no.5
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    • pp.662-669
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    • 2012
  • Bycatch and stranding of sea turtles from Jeju coastal water of Korea were monitered from 2008 to 2009. A total of 41 sea turtles, consisting of 12 greens (Chelonia mydas), 3 loggerheads (Caretta caretta), 1 hawksbill (Eretmochelys imbricata) and 25 unidentified species, were recorded and observed in those area. Reported stranding and bycatch reached to a peak in August. The largest number of bycatch occurred in the coastal waters around Aewol-eup located in northwest area of Jeju Island. Most of the bycatch were taken by set nets and gill nets, which prevailed over the fishing grounds in the coastal waters of the Jeju Island. It is suggested that an appropriate monitoring system be necessary to conserve endangered sea turtle species in Jeju of Korea.

Study on the Ecological and Taxonomical Characteristics of Zostera(Zosteraceae) in Korea I. Morphological and Environmental Characteristics of Zostera caespitosa Miki (한국산 거머리말속(Zostera, Zosteraceae)의 생태 및 분류학적 특성에 대한 연구 : I. 포기거머리말(Zostera caespitosa Miki)의 서식 환경과 형태적인 특징)

  • Lee, Sang-Yong;Kim, Tae-Jin;Heo, Seung;Choi, Chung-Il
    • The Korean Journal of Ecology
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    • v.24 no.3
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    • pp.149-156
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    • 2001
  • Zostera caespitosa Miki has been identified to be distributed along the seacoasts of Korea and Japan. This study was intended to clarify the morphological characters and the habitat characteristics of Korean Z. caespitosa. It was confirmed that Z. caespitosa is distributed along the seacoasts of South, Yellow and East Seas of South Korea. The habitats were located in the bay and port with the depth varying from 2.5 to 5.2 m. The habitats of Z. caespitosa were rather deeper than that of mixed bed with Z. marina. The sediment in the habitats was composed of well-sorted fine sand or muddy sand. Z. caespitosa showed marked differences in several morphological characters among sites. Morphology of Z. caespitosa varied with water depths, grain size and organic contents of sediments. Flowering shoots occurred by water temperature of 6.0∼13.7℃ from January to early April.

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Analysis of the Impact of QuikSCAT and ASCAT Sea Wind Data Assimilation on the Prediction of Regional Wind Field near Coastal Area (QuikSCAT과 ASCAT 해상풍 자료동화가 연안 지역 국지 바람장 예측에 미치는 영향 분석)

  • Lee, Soon-Hwan
    • Journal of the Korean earth science society
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    • v.33 no.4
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    • pp.309-319
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    • 2012
  • In order to clarify the characteristics of satellite based sea wind data assimilations applied for the estimation of wind resources around the Korean peninsula, several numerical experiments were carried out using WRF. Satellite sea wind data used in this study are QuikSCAT from NASA and ASCAT from ESA. When the wind resources are estimated with data assimilation, its estimation accuracy is improved clearly. Since the band width is broad for QuikSCAT, statistical accuracy of the estimated wind resources with QuikSCAT assimilations is better than that with ASCAT assimilations. But the wind estimated around sub-satellite point matches better with of ASCAT compared to QuikSCAT assimilation. The impact of sea wind data assimilation on the prediction of wind resources lasts for 6 hours after data assimilation starts, therefore the data assimilation processes using both fine spatial and temporal resolutions of sea wind are needed to make a more useful wind resource map of the Korean Peninsula.

Study on the reduction of green house effect gas emission by RORO ship coastal transport of import-export container cargo (RORO선을 이용한 수출입컨테이너화물의 연안운송에 의한 온실가스 배출량 삭감에 관한 연구)

  • Kim S. H.;Koh C. D.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.6 no.3
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    • pp.16-25
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    • 2003
  • In this paper, the reduction of green house effect gas CO₂ emission and NOx gas emission by using the RORO ship coastal transport of import-export container cargo was investigated. At first, the domestic CO₂ gas emission and the transportation of import-export container cargo were Investigated. Next, the characteristic of a RORO ship and CO₂ emission standard and NOx emission standard were investigated. And also, the reduction of CO₂ emission and NOx emission by the shift of coastal transport from land transport for the transportation of import-export container cargo between Kyongin area and Pusan Port were calculated. Finally, the change of CO2 and NOx gas emission due to the change of the share of coastal transportation and the load efficiency of RORO ship are investigated. The research results show that the shift of RORO ship coastal transport from land transport was very effective to reduce the CO₂ emission but it was no good to reduce the NOx emission.

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Examination of the Ground Remote Monitoring System for Coastal Environmental Elements - Marine Radar and Camera System - (연안 환경 요소에 대한 지상 원격 관측 방법 고찰 - 마린 레이다와 카메라 시스템 관측을 중심으로 -)

  • Kim, Tae-Rim;Jang, Seong-Woo
    • Korean Journal of Remote Sensing
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    • v.27 no.4
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    • pp.403-410
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    • 2011
  • Consistent observation with high temporal and spatial resolution is required for an efficient monitoring of coastal environments. Remote monitoring system installed on the ground is capable of simultaneous observation of wide coastal area and consistent observation with high frequency, which a small number of in-situ measurements cannot manage. This paper studies two typical ground based coastal monitoring system, marine radar and camera system. Marine radar can produce time series of frequency spectrum by integrating wave number spectrum calculated from spatial and temporal variation of waves in the radar image. The time averaged radar images of waves can analyze wave breaking zone, rip currents and location of littoral bars. Camera system can observe temporal variation of foam generation originated from coastal contamination as well as shoreline changes. By extracting the part of foams from rectified images, quantitative analysis of temporal foam variation can be done. By using the two above systems of different characteristics, synergetic benefit can be achieved.

Total Microbial Biomass Measured by ATP in Three Marine Sedimentary Environments (아데노신 3인산(ATP; Adenosine-5′ triphosphate)을 이용한 심해저 및 연안퇴적토의 총 미생물 생체량 측정)

  • 현정호;김경홍;권개경;이정현;이홍금;김상진;김기현
    • Korean Journal of Microbiology
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    • v.38 no.2
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    • pp.119-126
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    • 2002
  • ATP concentrations far estimating total microbial biomass in the sediment were measured in three different marine sedimentary environments. ATP concentrations were highest in the surface sediment and decreased with increasing sediment depth and distance from the land. The results indicated that the benthic microbial biomass is primarily controlled by nutrient inputs from the overlying water column. Because of the longer residence time and adsorption to the sediment, the variations in organic carbon (OC) contents with sites and depths were not as distinct as that of ATP, and the correlation between OC and ATP was not significant in the coastal sediments. No significant correlation between OC and ATP in the coastal sediments also suggested that microbial biomass in the labile organic-enriched coastal sediment is suppressed by the grazing of higher trophic level such as meiofauna. Overall regional and vertical distribution of ATP indicated that h\`w can be a relevant tool for measuring total microbial biomass in various marine sedimentary environments.

위성 영상과 해양 실측 자료를 활용한 부유사 농도 추정식 유도

  • Lee, Min-Seon;Park, Gyeong-Ae;Jeong, Jong-Ryul;Seo, Gang-Seon;An, Yu-Hwan;Mun, Jeong-Eon
    • 한국지구과학회:학술대회논문집
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    • 2010.04a
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    • pp.136-136
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    • 2010
  • 해색원격탐사에서 해수 type을 광학적 성질에 따라 Case-I water와 Case-II water로 구분한다. Case-I water는 기본적으로 조류 세포 및 그 쇄설물 그리고 미량의 용존 유기물을 포함하며, 맑은 해수인 대양이 이에 속한다. Case-II water는 부유 무기입자, 육상 기원입자 및 높은 용존 유기물 농도, 인간이 만든 유입물을 포함한 탁한 해수이며, 연안 해역의 해수가 이에 속한다(Gordon, 1983). Case-II water에 속하는 연안 해역의 부유사 농도는 해양 연안 환경 변화를 모니터링 할 수 있는 중요한 지표 중 하나이다. 부유사가 연안 환경, 연안 양식장, 어장 환경에 어떤 영향을 주는지 파악할 수 있다. 채수를 통하여 부유사 농도를 추정하는 것은 시간적 경제적 제약이 따른다. 하지만 위성자료와 실측 자료간의 상관관계가 잘 나타나는 계수를 유도하면, 실측없이 위성영상만 있으면 연속적인 부유사 농도 분포를 볼 수 있을 것으로 기대된다. 이런 목적으로 Landsat ETM+ 자료를 이용하여 광양만의 표층 부유사 농도를 추정하였다. 위성 통과시간에 맞춰 2009년 9월 22일과 11월 25일 2차례에 걸쳐 부유사 농도와 반사도를 광양만 16개 정점에서 측정하였다. 부유사 농도는 표층의 해수를 채수하여 GF/F 필터를 이용해 측정되었고, 반사도는 Spectroradiometer를 사용하여 350nm부터 1050nm까지 1nm 간격으로 측정되었다. Landsat ETM+ 자료와 실측 반사도는 원격반사도 $R_{rs}$로 변환되었고, 두 가지 $R_{rs}$를 실측 부유사 농도와 비교하여 부유사 농도 산출 계수를 유도하였다. 경험적으로 구한 계수를 사용하여 위성영상을 부유사 농도로 계산하였으며, 이는 같은 날의 실측 부유사 농도와 비슷한 공간분포를 나타내었다.

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Improving the Designation Criteria of Coastal and Marine Protected Areas through the Application of AHP (AHP를 이용한 연안.해양보호구역 지정기준 개선 연구)

  • Nam, Jung-Ho;Yook, Keun-Hyung
    • Journal of Environmental Policy
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    • v.6 no.3
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    • pp.57-89
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    • 2007
  • The Korean government has put mamy efforts into the protection of ecological values of coastal and marine ecosystems since the mid 1990s, recognizing ecological values and economic contributions of coastal and marine ecosystems. Rapid increase of coastal and marine protected areas in terms of number and size implies the innovative change of national policy regarding ecosystem protection. As of the end of 2006, the total number and size of the protected areas account for 425 and $10,666.8km^2$ respectively. Despite of this achievement, the current policy regime on the protected areas has not been quite successful dealing with in managerial issues. The ambiguity and the lacking objectivity of designation criteria have, been causes of pending issues such as conflict outbreaks, 'paper parks', duplicated designation, etc. This paper aims at improving current designation criteria based on AHP(Analytic Hierarchy Process). The suggestion of the study covers both the new designation criteria and the weighing factor on each criterion considering different ecological and socio-economic characteristics of 'wetland protected area' and 'marine protected area'.

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