• 한국수산과학회지
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• 제47권3호
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• pp.264-273
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• 2014

To investigate species composition and seasonal variation of demersal organisms in the coastal waters off the Taean peninsula, otter trawl surveys were conducted from April 2010 to January 2011. A total of 75 species were collected, including 44 species of Pisces, 19 species of Crustacea, 6 species of Cephalopoda, 4 species of Gastropoda, and 1 species each of Bivalvia and Echinoidea. The dominant species in each season were Palaemon gravieri in spring, Charybdis bimaculata in summer, Loligo japonica in autumn, and Crangon hakodatei in winter. The number of species, individuals and biomass were highest in autumn and lowest in winter. The diversity index was highest in summer and lowest in winter. The dominance index was highest in winter and lowest in summer. The richness index was highest in autumn and lowest in winter. The evenness index was highest in summer and lowest in autumn. A cluster analysis showed that demersal organisms were divided into two groups; spring and winter organisms (Group 1) and summer and autumn organisms (Group 2). We detected a significant difference (P<0.05) between these groups, mainly owing to Platycephalus indicus, Repomucenus koreanus, and Paralichthys olivaceus within Pisces: Trachysalambria curvirostris, Metapenaeopsis dalei, P. gravieri, and C. hakodatei within Crustacea: and L. japonica within Cephalopoda.

• 한국수산과학회지
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• 제44권5호
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• pp.506-515
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• 2011

To elucidate demersal organism community structure, abundance, and biomass by period and region in the Uljin marine ranching area, otter trawl surveys were conducted at six stations from February 2008 to December 2009. During the survey period, a total of 118 species was collected in the Uljin marine ranching area, including 76 pisces, 27 mollusca and 15 crustaceans. The average abundance of individuals was 806 ind./$m^2$ and average biomass was 31,853 g/m2. The numbers of species, species richness, individuals per area and biomass per area were higher in 2009 than in 2008. Cluster and MDS analysis, based on a Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into two different groups of demersal organisms in 2008 (Group 1) and one demersal organism community in 2009 (Group 2). From cluster and MDS analysis using the similarity of the demersal community among six stations, the Uljin marine ranching area was divided into Group A (St. 2, St. 4, St. 5 and St. 6) and Group B (St. 1 and St. 3).

• 수산해양기술연구
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• 제44권4호
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• pp.323-344
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• 2008

To examine species composition, abundance and biomass of demersal organisms in the East Sea, bottom trawl survey was conducted at 7 sea areas from 2005 to 2007. A total of 107 species were collected and were composed of 54 fish species, 16 crustacea, and 37 mollusks in the East Sea from 2005 to 2007. Yearly abundance per area which caught by trawl survey in the East Sea from 2005 to 2007 ranged from a high of $292,234inds./km^2$ in 2005 to a low of $192,092inds./km^2$ in 2006. The abundance by sea area showed a peak in 76 sea area, and the lowest in 63 sea area. The abundance per area by season showed a peak in summer, and the lowest in spring. The most dominant species in abundance were Clupea pallasii, Neocrangon communis, Chionoecetes opilio. Yearly biomass per area which caught by trawl survey in the East Sea from 2005 to 2007 ranged from a high of $10,322kg/km^2$ in 2006 to a low of $7,096kg/km^2$ in 2005. The most dominant species in biomass were Chionoecetes opilio, Clupea pallasii, Dasycottus setiger. The biomass by sea area also showed a peak in 76 sea area, and the lowest in 93 sea area. The abundance by season also showed a peak in summer, and the lowest in spring. As a result of cluster analysis, demersal organisms community of 76 sea area showed a large difference with other sea area, and that of summer showed a large difference with other season.

• 수산해양교육연구
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• 제28권1호
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• pp.211-220
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• 2016

Species composition of aquatic organism in the marine ranching area of Gunsan, Korea were investigated using shrimp beam trawl from May to December in 2010. A total of 91 species, $98,127ind./km^2$ and $877.6kg/km^2$ of aquatic organism were collected. Among them, species were included 60 species in Pisces, 21 in Crustacea and 10 in Mollusca. The individual dominant species, occupying over 10% of total individuals, were Latreutes anoplonyx($47,327ind/km^2$, 48.23%), Crangon hakodatei($11,578ind./km^2$, 11.80%) and Trachysalambria curvirostris($10,237ind./km^2$, 10.40%). And the biomass dominant species, occupying over 9% of total biomass, were Paralichthys olivaceus($135kg/km^2$, 15.4%), Okamejei kenojei($98.2kg/km^2$, 11.2%) and Portunus tribuberculatus($84.8kg/km^2$, 9.6%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per unit area collected more than two times during this survey by each month and station was divided into three different groups. Group A showed seasonal similarity of characteristic of distribution in August and November, Group B in December and Group C in May.

• 한국발생생물학회지:발생과생식
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• 제22권1호
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• pp.111-117
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• 2018

The objective of this study was to determine the mitotic intervals (${\tau}_0$) of two consecutive cell divisions and synchronous embryonic cleavage in grass puffer, Takifugu niphobles at different water temperatures (18, 20, 22, and $24^{\circ}C$). The color of the fertilized egg was light yellowish. The egg type was demersal and unadhesive. Egg weight was $0.09{\pm}0.002mg$. The sizes of unfertilized eggs were smaller than fertilized eggs in major axis and minor axis at $20^{\circ}C$ (p<0.05). The size of the fertilized egg of $18^{\circ}C$ water temperature group at the blastodisc stage was the smallest (p<0.05), but no significant differences were observed in the other water temperatures group except $18^{\circ}C$ water temperature group (p>0.05). The first cleavage stages at 18, 20, 22, and $24^{\circ}C$ were at 75, 90, 105, and 120 mins, respectively. As water temperature was increased, embryonic development and formation time of the first cleavage furrow were accelerated. There were negative correlation between ${\tau}_0$ and water temperature for grass puffer (Y=-1.225X+70.05, $R^2=0.988$, n=10, where Y was ${\tau}_0$ and X was temperature). This study confirmed that successful hatching of grass puffer was related to water temperature. Chromosome manipulation will be helpful for this species using cleavage frequency and ${\tau}_0$.

• 한국어류학회지
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• 제28권2호
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• pp.79-86
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• 2016

본 연구는 동해 남부 연안에서 출현하는 도화망둑 (Amblychaeturichthys hexanema)과 수염문절 (A. sciistius)의 위 내용물을 분석하여 두 어종의 위 내용물 조성을 조사하고, 종 간 그리고 성장에 따른 먹이자원의 분할이 있는지 연구하였다. 도화망둑과 수염문절은 저서성 갑각류를 주로 섭식하는 저서 섭식 육식성어류였다. 저서성 무척추동물과 부유성 먹이 또한 각각 도화망둑과 수염문절의 먹이로써 중요도가 다소 높았다. 중량비 자료를 이용한 non-metric multidimensional scaling (nMDS)와 다변량 분석 (multivariate analyses)에서 두 어종의 위 내용물 조성은 그 차이가 유의하였다. 그러나 두 어종 모두 성장에 따른 위 내용물 조성 변화에서 차이가 유의하지 않았다. 두 어종이 섭식한 먹이생물의 차이는 섭식 행동의 차이와 관련있다. 결론적으로, 본 연구해역에서 두 어종의 위 내용물 분석 결과는 도화망둑과 수염문절 사이에 생태지위 분리의 증거와 먹이 자원에 대한 종 간 경쟁 감소의 가능성을 보여주었다.

• 한국수산과학회지
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• 제47권6호
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• pp.945-959
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• 2014

This study was conducted to provide basic data for optimal fisheries management through the accurate understanding the catches, fishing level, species composition, distribution characteristics and fisheries status of trammel net in Gangwon Province. As the results of trammel net survey, Pisces were collected 77 species, 1,983.0 kg, Crustacea 9 species, 569.0 kg, Cephalopoda 5 species, 75.3 kg, Gastropoda 12 species, 16.5 kg in the coastal waters of Sokcho and Pisces 55 species, 3,681.5 kg, Crustacea 6 species, 2,229.8 kg, Gastropoda 10 species, 72.8 kg, Cephalopoda 4 species, 10.1 kg in the coastal waters of Donghae, respectively. The catches of important species with season and depths showed that the main target species is Pleuronectidae spp. at all depth and Aptocyclus ventricosus at <100 m in Sokcho, Liparis spp. and Dasycottus setiger at 200-500 m in Donghae, respectively. The mean total length (cm) of Gadus macrocephalus and Aptocyclus ventricosus didn't appear significant difference, but the mean total length of Pleuronectidae spp., Liparis spp. and D. setiger in Donghae is bigger than in Sokcho. From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed, catches data of dominant species in the coastal waters of Sokcho and Donghae was divided into three different groups of the demersal organisms community in 12 survey of Donghae (Group A) and Jul., Oct.-Dec. survey of Sokcho (Group B) and Jan.-Jun. and Aug.-Sep. survey of Sokcho (Group C).

• 한국수산과학회지
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• 제46권4호
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• pp.413-423
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• 2013

To elucidate the variation of species composition, biomass and length distribution of flatfishes by the period and region in the Uljin marine ranching area, bottom trawl survey was investigated at the six stations from Feb. 2008 to Dec. 2010. During the survey period, a total 4 families 17 species in the Pleuronectiformes, average 69,158 $ind./km^2$ and 5,625 $kg/km^2$ were identified, in 2008 appeared in 14 species, average 25,798 $ind./km^2$ and 2,333 $kg/km^2$ and in 2009 appeared in 13 species, average 102,360 $ind./km^2$ and 5,634 $kg/km^2$ and in 2010 appeared in 14 species, average 75,704 $ind./km^2$ and 8,632 $kg/km^2$. The individual dominant species, occupying over 10% of total individuals, was Pleuronectes herzensteini (20,811 ind., 30.0%), Hippoglossoides pinetorum (18,666 ind., 26.9%) and Glyptocephalus stelleri (13,499 ind., 19.4%) also the biomass dominant species, occuping over 10% of total biomass, was P. herzensteini (2,207 kg, 39.3%), Pleuronectes yokohamae (857 kg, 15.3%), H. pinetorum (761 kg, 13.5%), Kareius bicoloratus (677 kg, 12.1%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals in the Uljin marine ranching area from Feb. 2008 to Dec. 2010 was divided into two different groups of the flatfishes community in 2008 and from Jan. to Apr. in 2009 and 2010 (Group A) and the pleuronectiform community in from May to Dec. in 2009 and 2010 (Group B). From the cluster and MDS analysis using the similarity of demersal organisms community among six stations, the Uljin marine ranching area was divided into two different groups of Group 1 (St. 1 and St. 3) and Group 2 (St. 2, St. 4, St. 5 and St. 6).

• 수산해양기술연구
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• 제26권1호
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• pp.20-25
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• 1990

동지나해의 초음파산란층에 관한 기초적 연구로서 어군탐지기에 의해 탐지한 어군의 체적산란강도의 연직분포와 수온의 연직분포를 상호 비교\ulcorner검토하고, 또 트로올조업에 의한 어획시험을 행한 결과를 요약하면 다음과 같다. (1) 조사해역에서 표층에 가장 인접하여 형성된 수온약층의 수심구간은 8m~12m였고, 이 수온약층의 상\ulcorner하한에 대한 수온차는 8.6$^{\circ}C$였다. (2) 수온약층이 형성된 해역에 있어서 야간의 경우, 어군분포는 수온약층 상부의 혼합층에서 군집도가 가장 높았으나, 주간의 경우에는 수온약층에 관계없이 해저부근에서 어군의 군집도가 매우 높았다. (3) 본 조사에서 탐지한 어군의 각 수심층에 대한 평균체적산란강도의 최대치는 -49.3 dB~-48.0 dB 범위였다. (4) 주간에 해저부근에서 탐지한 어군의 평균체적산란강도의 최대치는 -48.6 dB로서, 이때 저층 트로올에 의해 어획된 어획물은 주로 게(Ovalipes punctatus)와 오징어(Photololigo edulis f. budo)였고, 이밖에도 약간의 쥐치(Thamnaconus modestus), 칼치(Trichiurus lepturus), 새우(Metanephrops thomsoni) 등이 어획되었다.