• 해양환경안전학회지
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• 제19권4호
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• pp.309-314
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• 2013

인공용승류 해역에서 난자치어의 종조성 및 시공간 변동을 파악하기 위하여 2012년 6월 13일, 9월 21일 및 25일에 난자치어 네트를 이용하여 조사하였다. 조사기간 동안 출현한 어란은 4,849 ind./$1,000m^3$, 자치어는 641 ind./$1,000m^3$이였다. 출현한 어란 중 가장 우점한 종은 멸치(Engraulis japonicus)로써 총 출현량의 약 57.5 %를 차지하였다. 그 외 미동정(Unidentified) 어란 I, II, III, IV이 출현하였다. 자치어는 청베도라치(Pictiblennius yatabei)가 가장 우점하였으며, 그 다음으로 돛양태류(Repomucenus sp.A, sp.B), 고등어(Scomber japonicus), 멸치(Engraulis japonicus), 전어(Konosirus punctatus) 등의 순으로 나타났다. 그리고 미동정(Unidentified) 자치어 I, II가 출현하였다. 대조구 해역에서는 어란은 멸치, 자치어는 돛양태류가 출현하였다. 시기별 변동에서는 어란 및 자치어 모두 7월에 가장 많았으며, 8월에 가장 낮았다. 정점별 변동에서는 인공용승이 일어나는 인근 정점인 2, 3번에서 어란 및 자치어의 출현량이 가장 많았다. 대조구 해역과의 비교하여 정점당 약 4배 이상 많은 어란 및 자치어가 출현하였다. 인공용승에 의한 영양염류 및 먹이생물의 증가로 인하여 어란 및 자치어의 출현량이 증가한 것으로 판단된다.

• 수산해양기술연구
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• 제54권4호
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• pp.287-295
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• 2018

The ichthyoplanktons were sampled to study distribution of the ichthyoplankton in coastal waters of Nanji-Island in August and November 2015 and January and May 2016. During the study, fish eggs of eight different species were collected. Engraulis japonicus was the most dominant species which accounted 44.80%. Sebastes schlegeli comprised 31.39% of the total larvae and juveniles. The diversity index of species per month of the collected juveniles at Nanji Island from 2015 to 2016 was 0.598-1.770 and the evenness index was 0.432-0.761. In case of dominance index was 0.619-0.897 against the evenness index. The analyzed species diversity index by the each station was 0.818-1.945 and the dominance index was 0.492-0.897 against the species diversity index. The months of August and May exhibited similar results. In addition, the community structure was very similar in state 2 and state 3.

• 한국수산과학회지
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• 제36권5호
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• pp.486-494
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• 2003

Distribution of ichthyoplanktons and its relation to environmental factors (temperature, salinity, $chlorophyll\;\alpha$) around the Youngsan River Estuary of Mokpo, southwest coast of Korea were investigated based on the samples collected bimonthly from February to December, 2001. Unidentified fish eggs were most abundant $1,345\;eggs/100m^3$ in August, while eggs of Engraulis japonicus were most abundant $63\;eggs/100m^3$ in June. A total of forty species of fish larvae and juveniles belonging to the twenty families under six orders were caught, with six gobiids, four icefishes, four croakers and three herrings being represented. Fish larvae and juveniles peaked $17,757\;inds./100m^3$ in August, which consisted of $91.02\%$ of gobiids, $3.69\%$ of gunnels and $3.67\%$ of icefishes, and they were most abundant $7,467\;Inds./100m^3$ at St. 7. Cluster analysis based on the individuals of fish larvae and juveniles showed that six months were classified into two groups at the dissimilarity 70, the first was composed of June and August and the second was February and December and April and October were not clustered with any other months. In August when species diversity index was the highest, eight stations were classified into two groups at the dissimilarity 70, the first was composed of St. 1, 3, 4, 5 and 8 and the second was St. 6, 7 and 2. As a result from correspondence analysis, there is no effect of the environmental factors with a density of fish eggs and larvae, but correlation could be found between a density of fish eggs and $chlorophyll\;\alpha.$

• 수산해양기술연구
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• 제55권3호
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• pp.243-251
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• 2019

The ichthyoplanktons were sampled by Bongo net to study the distribution of the eggs and larvae in the West coastal waters of Korea during the study period (February, May, August and October of 2017). Collected fish eggs were divided into Engraulis japonicus and unidentified species. The most dominant species, Engraulis japonicus accounted for 79.52% of the total fish egg, which was followed by unidentified species (20.48%). The total of 36 taxa in fish larvae were identified based on morphological and molecular characteristics. Fish larvae were dominant by Gobiidae species. 48.30% of the total catch in abundance, which was followed by Engraulis japonicus (31.86%). These two taxa composed 80.16% of the total collected fish larvae. The seasonal diversity index of species from the collected fish larvae in the West coastal waters in 2017 was 0.625-1.883 and the evenness index was 0.380-0.865. In addition, dominance index was 0.618-0.920 and richness was 0.573-3.189.

• 한국습지학회지
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• 제6권1호
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• pp.149-166
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• 2004

한강 하구의 염분 및 생태 환경에 관한 연구를 위하여 기존에 발표된 논문과 국립수산과학원의 국가해양환경측정망 자료를 이용하여 한강 하구의 염분 분포 특성을 구명하였으며, 염분과 연관하여 동식물플랑크톤, 저서생물 및 어류플랑크톤의 분포를 논의하였다. 염분의 시공간적 분포를 고려할 때 인천북항 주변 해역은 계절에 무관하게 연중 한강 유입수의 직접적인 영향을 받고 있으며, 담수 유입량이 많은 하계에는 팔미도 해역까지 담수 영향권이 확대되었다. 반면 해수의 직접적인 영향을 받는 상한선은 한강 본류인 경기도 김포시 고촌면 신곡리의 신곡수중보에 이르며, 해침이 상시적으로 발생하는 수역은 이보다 더 하류인 경기도 김포시 하성면 전류리로 판단된다. 동식물플랑크톤의 분포는 담수 및 해수 지역에서 혼재되어 분포하며, 일반적으로 염분의 분포 범위보다 훨씬 광범위한 분포를 보였다. 그러나 기수성 어류플랑크톤은 매우 제한된 수역에 분포하는 반면, 성어는 그 분포범위가 담수에서 해수에 이르는 광범위한 분포를 보였다. 경험적 분석에 의한 한강하구 환경의 문제점은 1)한강 하구 및 유수지역의 개발 압력에 따른 환경 파괴, 2)갯벌 매립에 의한 조간대 상실, 3)군사용 철책에 의한 육수전이환경(陸水轉移環境)의 생태적 단절이 매우 심각하였다.