• Title/Summary/Keyword: 하구역

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The Characteristic of Deposition in Nakdong estuary considering Tide and River discharge (조석과 하천수 유입을 고려한 낙동강 하구역의 퇴적특성)

  • Jeon, Yong-Ho;Ryu, Cheong-Ro;Lee, In-Cheol;Kim, Heon-Tae
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2003.05a
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    • pp.157-162
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    • 2003
  • Nakdong estuary is located at south-eastern coast of the Korea. A lot of sediment from upper river were deposited at this area. It has cause many problem such as changes in topography and tidal current. Changes of characteristic of deposition were cause by topographic change of nakdong estuary. Analyzing and evaluating data, we could predict the direction of movement of the sand bar and the growth toward south-eastern of Nakdong estuary. It was caused by decreasing river discharge after construction of Nakdong-kang barrage.

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한반도 하구역 실뱀장어 이석의 미세구조

  • 문형태;김광천;이태원
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2002.10a
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    • pp.266-267
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    • 2002
  • 실뱀장어 재료는 1998년 한국의 제주도 천제연, 낙동강 그리고 금강 하구 세 곳에서 실뱀장어 주 소상 시기 3개월 동안 채집하였다 실뱀장어는 조류가 강하고 어두운 밤에 활동성이 강하므로 각 월의 그믐 때 채집하였다. 제주도 천제연 하구에서는 손전등으로 빛을 비추고 뜰채(dip nets)를 이용해 채집하였다. 채집에 이용된 뜰채는 망직경이 20cm 정도이며 망목(stretched mesh width)은 1 mm 이었다. (중략)

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염색 표지 방류를 이용한 제주 천제연 하구 실뱀장어 자원량, 가입량 및 소상량 추정

  • 황선완;황선도;이태원
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2003.05a
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    • pp.289-290
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    • 2003
  • 제주도의 하구역에는 12월에서 5월 사이 실뱀장어가 나타나며, 주로 1월에서 3월 사이 나타난다. 2003년 3월 및 4월 초 제주 천제연 하구에서 주 소상시기인 그믐 전후 족대를 이용하여 실뱀장어를 잡아 표지 방류하여 자원량 및 가입률을 추정하였다. 피부 착색용 중성염료는 부착용 표지 방류가 어려운 자치어를 비롯한 소형어류 표지로 이용되어진다. (중략)

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Studies on the Environmental characteristics and Phytoplankton Community in the Nakdong River estuary (낙동강 하구 환경특성 및 식물플랑크톤의 군집구조에 관한 연구)

  • 문창호;최혜지
    • 한국해양학회지
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    • v.26 no.2
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    • pp.144-154
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    • 1991
  • After the completion of the Nakdong River estuary barrage, environmental characteristics and phytoplankton communities in the estuary were investigated from April to December, 1989. dissolved oxygen seems to have decreased in the just lower region of the barrage off Janglim, while ammonia and phosphate concentration increased, probably due to the waste discharge from the Janglim stream and stagnation of water after the barrage construction. Concentrations of nitrate and dissolved silicate were negatively correlated with salinity, suggesting that major source is the Nakdong River discharge. In April, there was a diatom (Asterinella sp.) bloom in the upper region of the barrage, while in July, a diatom (Skeletonema costatum) bloom in the estuary mouth. The green and blue-green algae in species composition seem to have increased after the barrage construction. The relatively high concentration of chlorophyll b in the upper region of the barrage probably result from the high density of freshwater green-algae there. Among the species occurred in the study area, many were indicative of water pollution. It seems that environmental characters and phytoplankton communities are changing after the barrage construction.

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Physical Environment Changes in the Keum River Estuary by the Dyke Gate Operation: I. Mean Sea Level and Tide (하구언 수문작동으로 인한 금강 하구역의 물리적 환경변화: I. 평균해수면과 조석)

  • Kwon, Hyo-Keun;Lee, Sang-Ho
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.2
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    • pp.93-100
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    • 1999
  • Analyzing the tide data taken at Kunsan inner and Outer ports, non-tidal and mean sea level and harmonic constants of major constituents are investigated to examine the effects of the dyke gate operation on the sea level change in Keum River estuary. Non-tidal and annual mean sea levels decrease at Kunsan Inner and Outer ports after the dyke gate operation, especially showing an abrupt drop of non-tidal sea level at Kunsan Inner port. This non-tidal sea level drop results in the mean sea level gradient change between the inner and outer port, which can be mainly explained in terms of the decrease of river discharge from the dyke. Amplitudes of the $M_2$ and $S_2$ tides at the Inner port increase after the dyke gate operation, showing an abrupt jump, and phases of both tides slightly decrease. Amplitude and phase of the $K_1$ and $O_1$ tides show slight changes after the dyke gate operation. This significant change of semi diurnal tide amplitude is believed as a result of superposition of incident tidal wave and reflected tidal wave from the dyke.

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