• 한국어류학회지
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• 제6권1호
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• pp.60-70
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• 1994

광양만 부유성 난 자치어의 종조성과 분포를 연구하기 위하여 1990년 2월부터 12월까지 6회에 걸쳐 8개 정점에서 부유성 난과 자치어를 채집하였다. 출현 분류군 수는 8월에, 출현량은 6월에 가장 많았다. 6개 분류군의 부유성 난 중에서, 멸치, 주둥치, 전어, 보구치가 99.1%를 차지하며 우점하였다. 21개 분류군의 자치어 중에서 멸치, 망둑어과, 전어, 보구치, 주둥치가 85.3%를 차지하며 우점하였다. 과거의 연구에 비하여 출현종수가 감소하였으며, 겨울 산란종인 까나리와 흰베도라치의 감소로 겨울에 출현량이 크게 감소하였다.

• 한국수산과학회지
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• 제43권6호
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• pp.751-755
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• 2010

To understand the function of nursery grounds, the seasonal variation of ichthyoplankton was investigated in the East Sea, off Dokdo, from September 2009 to May 2010. The dominant species was Engraulis japonicus (92.7%), which occurred in May and September. The next abundant species was Maurolicus japonicus (5.7%), found in all four seasons. Several rare warm-water species were found in September and November, when the species diversity was higher than in the other two seasons. Several fish species used Dokdo as a nursery ground for a restricted season, while M. japonicus used it in all four seasons.

• 한국수산과학회지
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• 제51권1호
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• pp.72-78
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• 2018

Fish eggs and larvae were collected in July and November of 2013 and January and May of 2014 to determine seasonal variation in the species composition of ichtyoplankton. Samples were classified based on morphological characteristics. Fish eggs were identified as belonging to five taxa; the most dominant species of fish eggs was Engraulis japonicus (62.05%) followed by Sardinops melanostictus (21.02%) and Leiognathus nuchalis (13.71%). These three species accounted for 96.8% of the total number of fish eggs collected. Larvae of 17 species in six families, and six orders were collected. The most dominant species of fish larvae was E. japonicus (51.79%), followed by L. nuchalis (12.59%) and Omobranchus elegans (12.08%). These three species accounted for 76.46% of the total number of larvae collected. Jinhae Bay was identified as a major spawning and nursery ground for fish species inhabiting in the south coast of Korea, such as E. japonicus, L. nuchalis, S. melanostictus, and Omobranchus elegans. Therefore, management of marine fish resources in the South Sea should necessarily include the ecological management of Jinhae Bay.

• 수산해양기술연구
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• 제24권4호
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• pp.135-143
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• 1988

To study the abundances of ichthyoplankton in the Nakdong River estuary, ichthyoplankton were sampled with standard net at approximately one month intervals from February, 1987 to January, 1988. Temperature and salinity in the study area showed large seasonal fluctuations due to the inflow of Nakdong River. Among 8 taxa of pelagic eggs occured in the study area, Sillago spp. occupied 37.3% of the total eggs; Coilia spp., 35.8%; Repomucenus spp., 13.7%; Engraulis japonica, 9.4%. These 4 taxa occupied 96.4% of the total eggs. Among 26 taxa of fish larvae, Engraulis japonica was the most abundant species and occupied 36.8% of the total larvae; Gobiidae, 15.3%; Repomucenus spp., 15.0%; Coilia spp., 14.0%; Hexagrammos otakii, 6.8%; Omobranchus elegans, 4.4%. These 6 taxa occupied 92.3% of the total larvae, The densities of pelagic eggs were more than 100 eggs/ 1,000m super(3) from May to October. The densities of larvae were 3.8~221.3 larvae/1,000m super(3). They were relatively high in May, July, and August.

• 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.

• 수산해양기술연구
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• 제55권3호
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• pp.233-242
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• 2019

Species composition and yearly variation of fish eggs and larval fishes were investigated from 2014 to 2016. During the study period, the fish eggs were identified as belonging to 14 taxa. The dominant species of fish eggs were Leiognathus nuchalis, Engraulis japonicus, and Konosirus punctatus. These three species accounted for 97.4% of the total number of individuals collected. The collected larval fishes were identified into 37 taxa, 22 families, and seven orders. The dominant species of larval fish were Leiognathus nuchalis, and Gobiidae fishes. These three species accounted for 85.4% of the total number of individuals collected. The diversity index of the larval fishes was the highest in 2014 (H' = 1.60) and the lowest in 2015 (H' = 1.15). The evenness index was the highest in 2016 (J = 0.51) and the lowest in 2015 (J = 0.39). The dominance index was the highest in 2015 (D = 83.5%) and the lowest in 2016 (D = 70.9%). In addition, the economically important species in this area were Engraulis japonicus, Konosirus punctatus, Hippocampus coronatus, Sebastes schlegelii, Acanthopagrus schlegeli, and Cynoglossus joyneri.

• 한국어류학회지
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• 제19권4호
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• pp.332-342
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• 2007

이 연구는 경상북도 울진 연안 해역에서 2002년 1월, 4월, 7월 및 10월까지 계절별로 총 4회에 걸쳐 만조시에 채집된 부유성 난 자치어의 종조성, 양적변동을 연구하였다. 연구기간 동안 채집된 부유성 난은 총 7개 분류군이 출현하여 멸치, 정어리, 까나리, 참가자미속 어류, 앨퉁이, 보리멸, 기타 난 등으로 분류되었고, 출현량을 보면, 멸치 난이 연구기간 동안 출현한 부유성 난의 38.34%를 차지하여 가장 우점도가 높았으며, 보리멸 난이 25.84%를 차지하였다. 연구기간 동안 출현한 자치어는 총 7목 18과 25개의 분류군이 출현하였고, 멸치가 연구기간 동안 출현한 자치어의 90.46%를 차지하여 최우점종이었으며, 다음으로 조피볼락이 자치어의 2.04%를 차지하였다. 이들 2종이 차지한 비율은 92.49%이었으며, 나머지 23개 분류군은 7.51%를 차지하였다. 2002년 울진에서 계절별 종 다양도지수(H')는 0.0878~2.3855였고, 균등도지수는 0.0451~0.9300로 나타났다. 우점도의 경우는 0.3000~0.9914로 종 다양도지수와 균등도지수와는 반대 경향을 보였다. 정점별로 분석한 종 다양도지수는 0.3035~0.7440으로 정점 2에서 가장 낮은 값을 나타냈고, 정점 1에서 가장 높은 값을 보였다. 우점도의 경우는 0.8919~0.9669로 종 다양도지수와 균등도지수와는 반대 경향을 보였다. 계절별 군집의 유사도는 여름과 가을에 상대거리 차(0.010)가 가장 적어 군집상이 매우 유사하였고, 정점별로는 정점 1과 정점 4에서 가장 적은 상대거리 차(0.014)를 보여 군집상이 매우 유사하였다.

• 한국수산과학회지
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• 제27권5호
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• pp.633-642
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• 1994

고리 주변 해역의 부유성 난과 자치어 분포를 조사하기 위하여, 1991년 4월, 7월, 10월 및 1992년 1월 4회에 걸쳐서 RN 80Net를 이용하여 부유성 난과 자치어를 표층 채집하였다. 본 해역에서 출현한 부유성 난은 멸치, 앨퉁이, 동갈양태속어류 및 기타로 분류되었는데, 조사 기간중 멸치는 전체 어란 출현량의 $79.52\%$를 차지하여 우점종으로 나타났다. 자치어는 총 15개 분류군이 출현하였다. 조사 기간중 멸치는 전체 자치어 출현량의 $52.39\%$를 차지하여 극우점종으로 나타났으며, 동갈양태속어류가 $29.36\%$를 차지하여 우점종으로 나타났다. 그 이외에도 쥐치, 조피볼락, 까나리 및 벵에돔이 주요 출현종을 이루었다. 이들 6개 분류군은 자치어 출현량의 $94.30\%$를 차지하였다. 본 해역의 연안쪽에서는 온배수 영향으로 배수구에 인접한 정점에서는 자치어 분포에 큰 영향을 미치는 것으로 나타났으며, 외해쪽에 서는 용승류로 인한 표층수의 이동이 부유성 난과 차지어 분포에 영향을 미치는 것으로 나타났다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.26-27
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• 2001

Two sea survey instruments were introduced: continuous underway fish egg sampler (CUFES) and an airborne light detecting and ranging (LIDAR) for survey of epiplegic fish. We have used CUFES in ichthyoplankton surveys primarily for Pacific sardine (Sardinop sagax) eggs off California since 1996 and it is also being used in many parts of world for sardine and anchovy egg surveys. (omitted)

• Ocean Science Journal
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• 제40권1호
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• pp.11-16
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• 2005

Correction factors based on the catch ratios of egg and larval densities in the southern waters of Korea were estimated for anchovy Engraulis japonica. This was undertaken in order to adjust ichthyoplankton data from different sampling methods, gear types and time. Samples were collected during ichthyop1ankton surveys in Korean waters from 1983 to 1994. The ratios for egg densities obtained in vertical tows with a NORPAC net (ring $\Phi$, 45 cm) compared to those obtained in oblique tows with a KOB net (ring $\Phi$, 80 cm) were 0.86 (CV = 0.65), 1.22 (CV = 0.36), and 0.93 (CV = 0.42) for early, middle, and later developmental stages, respectively. The ratios for larval densities for vertical and oblique tows varied depending on size. For yolk-sac and small larvae (< 4 mm), the ratios were 3.08 (CV = 0.45) and 1.98 (CV = 1.34), while those of 4-6 mm, 6-8 mm, and 8-10 mm larvae were 0.44 (CV = 1.31), 0.45 (CV = 1.70), and 0.56 (CV = 2.50), respectively. Ratios of day/night densities for larvae of 4-10 mm lengths were lower (0.01-0.06) in offshore catches than values obtained in coastal areas (0.440.46) and similar values (0.16-0.04) for vertical and oblique tows. Our results indicated that vertical towing is more efficient for sampling early life stages (from eggs to larvae less than 4 mm long), while oblique towing is more efficient for larvae longer than 4 mm due to depth preferences for each developmental stage (e.g., changes in egg buoyancy and vertical migration oflarvae).