• 제목/요약/키워드: sea environment

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Tributyltin Compound in Sediments and Tissues of Oysters and Rock Shell in Gwangyang Bay, Korea

  • Shim, Won-Joon;Yim, Un-Hyuk;Kim, Nam-Sook;Hong, Sang-Hee;Oh, Jae-Ryoung
    • 환경생물
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    • 제22권
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    • pp.63-70
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    • 2004
  • Tributyltin (TBT) and its degradation products, dibutyltin (DBT) and monobutyltin (MBT) were quantitatively determined in surface sediments and two molluscan species, Pacific oyster (Crassostrea gigas) and rock shell (Thais ctavigera), from Gwangyang Bay, Korea. Butyltin compounds were detectable in almost all sediment and biota samples. Tributyltin concentrations in surface sediment ranged<2∼33 ng g$\^$-1/, which is at a lower end of TBT concentrations in industrialized bays in Korea. However, TBT levels in sediments were related to boating activities around the bay. In biota samples, TBT concentrations were in the range of 178∼2,458 ng g$\^$-1/ toy oyster and 47∼236 ng g$\^$-1/ for rock shell. Relatively high TBT concentrations in biota were found near wharves for fisherboats and harbor areas. About 90∼100% of the female T. clavigera displayed imposex, and relative penis length index of the imposexed-female was in the range of 20.9∼107.9%. Furthermore, TBT body residue had a significant positive relationship with degree of imposex in T. clavigera. Overall, TBT concentrations in Gwanyang Bay were much lower than other major bays in Korea.

여수 돌산도 연안 낭장망에 부수어획된 어류 종조성 (Species Composition of Bycatch Fishes Collected by a Gape Net with Wings in the Coastal Waters of Dolsan-do, Yeosu, Korea)

  • 정재묵;유준택;김희용;이선길;고우진;김영혜
    • 한국수산과학회지
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    • 제48권5호
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    • pp.805-809
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    • 2015
  • The species composition of bycatch species in the coastal waters of Yeosu were determined by monthly sample collection using a gape net with wings in 2014. Of a total of 32 fishes collected, the dominant species were Ammodytes personatus, Conger myriaster leptocephali, Sebastes inermis, Trichiurus lepturus, Thryssa kammalensis, Leiognathus nuchalis, Syngnathus schlegeli, Thryssa adelae and Hexagrammos otakii. These 9species accounted for 95.2% of the total number of individuals collected. Most of the fish caught were juveniles and small fishes. Based on the results of multidemensional scaling (MDS) analysis, the bycatch fishes were divided into five group.

황해 동부해역 표층퇴적물의 중금속 농도 분포 (Distribution of Heavy Metal Concentrations in Surface Sediments of the eastern Yellow Sea)

  • 선철인;박건우;박현실;박준건;김성길;최만식
    • 한국해양학회지:바다
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    • 제23권4호
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    • pp.179-191
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    • 2018
  • 황해 동부해역 표층퇴적물의 중금속 분포 특성을 파악하기 위하여 입도, 유기탄소(TOC)와 함께 중금속 원소들(Cu, Pb, Zn, Cd, Cr, Mn, As, Ni, Co, Li, Fe, Al)의 농도를 분석하였다. 연구결과에 따르면, 일부 정점에서 Pb, Mn, As를 제외하면 모든 중금속 농도의 분포는 입도 및 TOC의 분포와 유사하게 황해 중앙해역에서 상대적으로 높고, 한국 연안으로 갈수록 감소하는 경향을 보였다. 입도와 중금속 농도간의 관계를 통하여 대부분의 금속은 입도가 세립할수록 농도가 높게 나타나는 일반적인 경향을 보였다. 그러나 일부 정점에서 Pb은 조립질 퇴적물에서의 암석기원(feldspar) 영향, Mn은 생물기원($CaCO_3$) 영향, As는 중광물(pyrite) 특성에 따라 분포 양상이 다르게 나타났다. 과거에 조사한 자료(2000년)와 비교했을 때, 황해 동부해역에서 지난 15년 동안의 추가적인 중금속 농축은 없었고, 투기해역에 대한 저질환경은 과거에 비해 크게 개선되지 못한 것으로 나타났다. 연구해역 내 모든 중금속의 농도는 한국과 중국에서 규정하고 있는 최소기준(TEL, MSQ-1)보다 낮았지만, 농축지수(enrichment factor; EF), 농집지수(geo-accumulation index; $I_{geo}$), 생태위해성지수(ecological risk index; ERI)는 Cu, Pb, Zn, Cr이 황해 중앙해역에서 상대적으로 높게 나타났다.

해상에서 적외선신호의 계측절차 및 분석기법 연구 (A Study on Measuring Procedure and Analysis Technique of Ship Infrared Signature at Sea)

  • 조용진
    • 한국해양공학회지
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    • 제23권3호
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    • pp.53-58
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    • 2009
  • A scale model test for ship Infra-Red signature measurements at sea is impossible, because it is sensitive to the environment. Since we can't control the meteorological environment of the real sea, it can't be carried out with the desired maritime environments. Therefore, in the sea, we made measurements of the weather, operating conditions of the ship, and ship IR signatures under given conditions, and then analyzed them. Conversely, we compared the results of the test with a prediction for a given scenario condition. This paper describes the test items, procedures, and measuring instruments of the experiments at sea and the results from basic researches for methods of estimation and analysis of the measured data.

중국 송대 해선의 주요유형에 관한 연구 (A Study on the Main Sea-Going Ship's Type of Chinese Song Dynasty)

  • 최운봉;허일
    • 해양환경안전학회지
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    • 제10권1호
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    • pp.35-40
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    • 2004
  • 선박은 물을 떠날 수 없고, 항로의 자연환경에 따라 항행해야 하기 때문에 항행하는 해역환경에 의하여 선박의 특성이 결정된다. 중국의 남방과 북방의 해역은 상이한 특징을 가지고 있다. 즉 남방의 해역은 수심이 갚고, 북방의 해역은 수심이 얕다. 중국의 조선기술은 이러한 해역특성에 적응하여 상이한 선형이 발명, 발전되었다.

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A New Free-Living Marine Nematode, Chaetonema longicorpus sp. nov. (Enoplida: Anoplostomatidae) from a Subtidal Zone of the East Sea, Korea

  • Lee, Hyo Jin;Lee, Heegab;Rho, Hyun Soo
    • Animal Systematics, Evolution and Diversity
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    • 제38권4호
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    • pp.205-213
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    • 2022
  • A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

동해구외끌이중형저인망에 의한 동해 중남부 해역 저어류의 종조성 및 군집구조 (Species Composition and Community Structure of Demersal Fish Caught by a Danish Seine Fishery in the Coastal Waters of the Middle and Southern East Sea, Korea)

  • 손명호;박정호;윤병선;최영민;김진구
    • 한국수산과학회지
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    • 제48권4호
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    • pp.529-541
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    • 2015
  • We examined the species composition and community structure of demersal fish in the middle and southern coastal waters of the East Sea of Korea by surveying a commercial Danish seine fishery from 2010 to 2013. We considered the waters north of $37^{\circ}N$ as middle and those south of $37^{\circ}N$ as southern waters. A total of 79 demersal fish species belonging to 18 families were collected. Of these, 59 species (77.6%) inhabited only the East Sea as opposed to the West and South Seas of Korea, and most were resident species. The species and biomass were similar between the two portions of the study area. The sandfish Arctoscopus japonicus (78.0%) and the blackfin flounder Glyptocephalus stelleri (65.1%) were the most common species and accounted for the most biomass in the middle and southern waters, respectively. Fish were most abundant at shallow depths (50-100 m) in the middle portion of the East Sea. Using a cluster analysis, we divided the species composition and community structure at the sampling stations into three groups: middle portion (group A), deep area of the southern portion (group B), and shallow areas of the southern portion (group C). A. japonicas and G. stelleri were dominant in groups A and B, while G. stelleri and Clupea pallasii were dominant in group C.

Water and Salt Budgets for the Yellow Sea

  • Lee, Jae-Hak;An, Byoung-Woong;Bang, Inkweon;Hong, Gi-Hoon
    • Journal of the korean society of oceanography
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    • 제37권3호
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    • pp.125-133
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    • 2002
  • Water and salt budgets in the Yellow Sea and Bohai are analyzed based on the historical data and CTD data collected recently using box models. The amounts of volume transport and of water exchange across the boundary between the Yellow and East China Seas are estimated to be 2,330-2,840 $\textrm{km}^3$/yr and 109-133 $\textrm{km}^3$/yr, respectively, from the one-layer box model. Corresponding water residence time is 5-6 years. In the Bohai, water residence time is twice as long as that in the Yellow Sea, suggesting that the Yellow Sea and Bohai cannot be considered as a single system in the view of water and salt budgets. The results indicate that water and salt budgets in the Yellow Sea depend almost only on the water exchange between the Yellow and East China Seas. The computation with the coupled two-layer model shows that water residence time is slightly decreased to 4-5 years for the Yellow Sea. In order to reduce uncertainties for the budgeting results the amount of the discharge from the Changjiang that enters into the Yellow Sea, the vertical advection and vertical mixing fluxes across the layer interface have to be quantified. The decreasing trend of the annual Yellow River outflow is likely to result that water residence time is much longer than the current state, especially for the Bohai. The completion of the Three Gorges dam on the Changjiang may be change the water and salt budgets in the Yellow Sea. It is expected that cutting back the discharge from the Changjiang by 10% through the dam would increase water residence time by about 10%.

Distribution and Characteristics of PAHs in Bivalves from Gwangyang Bay, Korea

  • Yim, U.H.;Hong, S.H.;Shim, W.J.;Oh, J.R.
    • 환경생물
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    • 제22권
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    • pp.78-85
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    • 2004
  • Polyeyclic aromatic hydrocarbons (PAHs) were quantitatively determined in bivalves from Gwangyang Bay. Twenty-four kinds of target PAHs were detected in the entire samples. Total PAHs concentrations ranged 86.1∼1,210 ng g$\^$-1/ dry weight with a average concentration of 309 ng g$\^$-1/, which is much lower than those of other industrialized bays in Korea. Strong tidal currents and artificial interferences like reclamation and dredging activity were suggested as major reason for disparity between highly industrialization and low contamination status. There was no correlation between total PAHs and lipid contents, implying that lipid content is not the one major parameter for the accumulation of PAHs by bivalves. Input sources were inferred as petrogenic and pyrogenic PAHs. With help of PCA analysis, signals of seasonal variations, not only concentrations but also compositions were found.

새만금 해양환경에서 해수 중 유기인계 농약의 시공간적 분포 (Spatial and Temporal Distribution of Organophosphorus Pesticides in Seawater from Saemangeum Area)

  • 이동호;홍상희;심원준;박준건;김은수
    • Ocean and Polar Research
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    • 제28권3호
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    • pp.331-337
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    • 2006
  • Organophosphorus pesticides (OPs) were analyzed in surface water samples from the Saemangeum environment. IBP was the most abundant among 10 OPs analyzed, and accounted fur over 95% of total amount of OPs. Concentrations of IBP measured in Mangyeong River water and surface seawater ranged from 670 to 1100ng/l and from 45 to 1000 ng/l, respectively. In general, a decreasing trend of OP concentrations towards open sea was observed. The concentrations of IBP and salinity demonstrated a strong correlation $(r^2=0.96)$. This indicates that IBP showed conservative behavior in the study area, and seawater dilution is a major factor affecting distribution and variation of OPs in the Sammgem environment.