• Title/Summary/Keyword: 延安

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인천만 개발에 따른 조석체계의 변화

  • 정신택;소재귀
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1993.07a
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    • pp.156-159
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    • 1993
  • 국토가 좁고 자원이 빈약한 우리나라는 연안역에 대한 보다 효율적이고 종합적인 이용이 절실이 요구되고 있다. 특히 항만 설설, 호안 및 방파제의 건설 등 연안개발 사업은 막대한 초기 투자비와 유지 관리비가 소요되기 때문에 파랑, 흐름, 퇴적물 이동 등의 설계환경요소들을 정확히 예측하는 것이 필요하다. (중략)

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Subfamily Anadarinae (Bivalvia : Arcidae) of the Russian Far East Coast) (러시아 극동 연안의 꼬막 아과 (이매패 : Arcida))

  • Lutaenko, Konstantin A.
    • The Korean Journal of Malacology
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    • v.9 no.1
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    • pp.27-32
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    • 1993
  • 러시아의 극동 연안에서는 꼬막 아과 세 종이 출현하고 있다. 이들 중 Anadara inaequivalvis(Bruguiere, 1789)와 Anadara subcrenata(Lischke, 1869)는 신생대에 전멸된 개체군으로 알려져 있다. Anadara속의 형태학적 변이, 분류 및 지리적 분포에 대한 자료를 제시하였다.

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목포연안 여객선 효율적 안전관리 방안에 대한 고찰

  • Kim, Seung-Rin;Kim, Hyeon-Seong;Mun, Hyeon-Jin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2019.11a
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    • pp.45-47
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    • 2019
  • 목포연안에 존재하는 다수의 여객선과 항로를 관리함에 있어 여객선 현황, 해양사고의 원인 및 운항변수에 따른 위험요소를 분석하고 효율적인 안전관리방안 제시.

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Environmental Factors and Catch Fluctuation of Set Net Grounds in the Coastal Waters of Yeosu 3. The Quantity of Phytoplankton and Catch Fluctuation. (여수연안 정치강어장의 환경요인과 어항변동에 관한 연구 3 . 기초생산자의 출현과 어획량의 변동)

  • Kim, Dong-Soo;Rho, Hong-Kil
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.1
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    • pp.15-23
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    • 1995
  • In order to investigate the relation between the phytoplankton and the catch fluctuation of set net fishing grounds located in the coastal waters of Yeosu, phytoplankton observations on the fishing ground were carried out by the training ship of Yeosu, Fisheries University from April to November in 1990, and the data obtained were compared with the catch data from the joint market of yeosu fisheries cooperative society in 1990. The results obtained are summarized as follows: 1) The phytoplanktons were more appeared in summer than in spring or autumn and their quantity was much in the shore of Dolsan-do, and little in the offshore waters distributed in the shores of Sori-do and Sejon-do, Thus, the quantity of the planktons could be used for estimating the distribution of watermass. 2) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel > Hair tail > Common mackerel > Sardine > Anchovy > Horse mackerel > Yellow tail. The catches of anchovy and Sardine were high in April to May and Hair tail. Horse mackerel and Common mackerel were caught from June to October. But Spanish mackerel were caught during the whole period of fishing. 3) The catches by set nets showed a correlation with the quantity of phytoplanktons. The planktons appeared most in the inner waters. influenced largely by the inflow of land waters in summer. and the catches were high in summer when the offshore water was distributed least. Therefore, the most important factor influencing the catches were regarded to be the productivity of food organism in inner water into which abundant nutrients were supplied by the inflow of land waters. That is, the fluctuation of catches by set nets seemed to be influenced mainly by the productivity of food organism.

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Pollution and Ecological Risk Assessment of Trace Metals in Surface Sediments of the Ulsan-Onsan Coast (울산-온산연안 표층퇴적물 내 미량금속 오염도 및 생태위해성 평가)

  • Sun, Chul-In;Kim, Dong-Jae;Lee, Yong-Woo;Kim, Seong-Soo
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.4
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    • pp.245-253
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    • 2015
  • Total acid digestion and 1 M HCl extraction methods were used to investigate the pollution status and the degree of ecological risk of trace metals in surface sediments from the Ulsan-Onsan coast. Total concentrations of trace metals (Cu, Cd, Pb, Zn, and Hg) were two-fold higher in surface sediments from Onsan coast than in those from Ulsan coast. The mean labile fractions of the total concentrations of Cd and Pb were 72% and 78%, respectively, indicating a high contribution from anthropogenic sources, whereas Cr, Li, Ni, and As in the residual fraction exceeded 80%, indicating a high contribution from natural sources. According to the results of assessment of trace metal pollution using the sediment quality guidelines in Korea, the concentrations of Cu, Pb, Zn, and Hg were higher than the values of the probable effects level (PEL) at some stations of Onsan coast, and the concentrations of Cr and Ni were lower than the values of the threshold effects level (TEL). The pollution level and ecological risk of the trace metals were analyzed using various indexes (EF, $I_{geo}$, m-PEL-Q, and ERI). Our results showed that the degree of pollution by trace metals (Cu, Cd, Pb, Zn, and Hg) on the Ulsan-Onsan coast was high, and Hg and Cd were the major potential ecological risk factors.

Analysis on the Area of Deltaic Barrier Island and Suspended Sediments Concentration in Nakdong River Using Satellite Images (위성영상을 활용한 낙동강 삼각주 연안사주의 면적 및 부유퇴적물 농도 변화 분석)

  • Eom, Jinah;Lee, Changwook
    • Korean Journal of Remote Sensing
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    • v.33 no.2
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    • pp.201-211
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    • 2017
  • The estuary in Nakdong River has changes by the construction of harbors, land reclamation and artificial waterway changes. These resultslead to changes of extinction and creation of deltaic barrier island. The deltaic barrier island changes in the Nakdong River estuary affect the function of the barrier islands and cause environmental changes. Therefore, it is important to monitor the changes in the area of the Nakdong estuary. In this study, long-term changes of the area and suspended sediment of deltaic barrier island in the Nakdong River estuary were analyzed using Landsat TM/ETM+ images. As a result, end point rate (EPR) values of shoreline in Jinwoodo and Sinjado are about 5m/yr and about 50 m/yr, respectively. The EPR values of north-south and east-west direction in Doyodeung are 20 m/yr and -20 ~ 10 m/yr. The suspended sediment concentration (SSC) has a maximum value of $25g/m^3$ in the vicinity of Jinwoodo and Sinjado, while it has a maximum concentration of $40g/m^3$ in the vicinity of Shinjido and Doyodeung. In other words, the area and the SSC change are small in Jinwoodo, and the area change and the SSC variation are large in Sinjado and Doyodeung. As a result of analysis of correlation between area change and SSC variation using all data, the Pearson coefficient value (r) is 0.36 and it is 0.32 in winter data. In other words, it is considered that the SSC variation affectsthe deltatic barrier island area change. However, verification using advanced altimetry data is necessary in the future. These studies can be used for coastal monitoring and environmental monitoring.