• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.39-54
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• 2005

Seasonal variation in species composition of fish in the Geum River estuary was determined using monthly samples collected with a bag net from February to December 2003. Of a total of seventy-three species collected, four groups of fishes were distinguished. Estuarine fishes such as Chelon haematocheilus and Synechogobius hasta were collected almost all the seasons and predominated in abundance during cold months. Coastal fish species such as Sardinella zunasi, Konosirus punctatus, Engraulis japonicus, Johnius grypotus and Thryssa kammalensis were dominated from late spring to autumn. Their adults entered into the estuary in spring and a large number of their juveniles were collected in summer and autumn till moving out to deeper waters for over-wintering. A few freshwater fishes were collected when the freshwater was discharged during the rainy season. Anguilla japonica elvers (diadromous fish) and Coilia nasus (amphidromous fish) were collected in spring during their upstream migration. The principal component analysis revealed that the seasonal variation in species composition of fishes was principally determined by water temperature and/or water temperature related factors.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.151-162
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• 2008

Chromosome analysis using karyotyping and bicolor FISH were carried out in Pimpinella hallaisanensis which is one of the endemic plants in Jeju island of Korea. The somatic methaphase chromosomes number of this plant was 2n=2x=22 and the size of this chromosomes ranged from 3.58 to $5.82{\mu}m$. The chromosome complements consisted of two pairs of metacentrics (chromosomes 1 and 2), four pairs of submetacentrics (chromosomes 3, 4, 6 and 8) and five pairs of subtelocentrics (chromosomes 5, 7, 9, 10 and 11). Using bicolor FISH, three pairs of 5S and four pairs of 45S rDNA loci were observed. Two pairs of 5S rDNA signals were detected on the end of the long arm of chromosome 4 and one pair of them were observed between long arm end and centromere. Another 45S rDNA signals were detected on the end of short arm of chromosome 4, 6, 10 and 11, respectively. Hence, the chromosome number reexamined using both conventional staining and FISH methods was different from previous report.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.76-83
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• 2017

Fish respond sensitively to light, so it is possible to develop fish management technology using this feature. In this study, we developed a light-based fish barrier and analyzed itsblocking effect using the difference in illuminance for the major fish species in Korea, bass and bluegill. The light was generated by a light emitting diode and the facility was installed vertically from the bottom. Considering the fish's ability to travel upstream, the flow rate was divided into three stages (0.2, 0.1, and 0.05 m/s). To prevent the learning effect, an experiment was carried out with fish that had rested for more than one day in a rearing tank. The experiment was carried out in such a way as tocompare the number of fish which travelled upstream after the introductionof the fish barrier and that of the fish which travelled upstream after itsremoval. It was also carried out after sunset to increase the effectiveness of the barrier. According to the results of the experiment, the fish blocking effect depending on the difference in illuminance was high and, overall, the blocking rate for bass was lower than that for bluegill. Based on the total size of the experimental population, the blocking rates for bass and bluegill were 96.33% and 99.00%, respectively. Based on the number of fish that travelled upstream, the blocking rates for bass and bluegill were 91.73% and 98.73%, respectively.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.490-498
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• 2008

This study was to analyze fish composition and ecological indicator characteristics from eight sampling sites of Geum River, October 2007. Total number of family and species sampled were 9 and 40. The most dominant family was Cyprinidae (27 species, 85%), and then followed by Cobitidae, Odomtobutidae, and Gobiidae. Constancy values of Zacco platypus and Zacco temminckii were 1.00 and 0.30, respectively, and the relative abundance of Acheilognathus koreensis and Pseudogobio esocinus were greater than 5% of the total. The number of Korean endemic species sampled in this Geum River study was 7 family 19 species, which is 47.5% of total 40 species, and endangered species of Pseudopungtungia nigra and Gobiobotia brevibarba were only 0.5% of the total and these species were only distributed within the upstream regions. Exotic species, Micropterus salmoides, which is known as large-mouth bass, were observed in two sites of G3 and G7. Analytical results of fish community showed that community dominance index was 0.19, which is low, and the species evenness index (0.74), diversity index (2.03), and richness index (3.00) appeared high. These results indicate that structure of fish community is stable in the Geum River. According to various guilds analysis, the relative abundance of tolerant and omnivores at all sites were 40% and 47% of the total, respectively. This monitoring data may contribute changes of fish fauna and compositions in relation to habitat modifications and chemical water quality degradations in the future.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.104-115
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• 2015

The species composition of larval fish assemblages in the Nakdong River estuary, Korea, was determined using monthly samples collected between September 2010 and August 2011 at two stations. A total of forty three larval species were collected during the study. Among forty three taxa of fish larvae, summer gobies, Clupea pallasii, Engraulis japonicus, spring gobies, Konosirus punctatus, winter gobies, Sardinops melanostictus, Coilia nasus were dominant taxa, and these eight taxa accounted for 95.0% in the total number of individuals. Species composition and abundance varied greatly spatio-temprally showing the peak abundances of fish larvae in August 2011, and a few fish larvae were occurred in November 2010. Cluster analysis based on the number of individuals of fish larvae showed that 21 month-station sampling units were classified into five groups at the similarity level of 50%, and the results of ANOSIM and SIMPER analysis revealed significant differences in community structure among five groups.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.37-43
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• 1989

The purpose of this study is to find the light intensity which induced maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by suing Rudder fish, Girella punctata(Gray). An experimental tank(360L*50W*55H cm) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Eight artificial light sources were prepared by combination of three light bulbs(10W, 60W, 100W) and eight filters. During the experiment water depth was maintained 50cm level in the tank. The tank was marked into six longitudinal sections each being 60cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 60 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 2.98 lux(1.90-4.40 lux) at daytime and 298.56 lux(188.44-444.96 lux) at night. The variation of the gathering rate of fish in illumination time was great and irregularly fluctuated, but did not show any definite pattern. It was somewhat difference between daytime and night.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.139-145
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• 2013

This study was carried out to determine the karyotype and chromosomal localizations of 45S and 5S rDNAs using FISH in Astragalus koraiensis. The somatic metaphase chromosome number of this species was 2n = 16 with basic chromosome number of x = 8. The karyotype of A. koraiensis was consisted of six pairs of median region chromosomes(chromosome 1, 3, 4, 5, 6, 8) and two pairs of submedian chromosomes(chromosome 2, 7). Based on the FISH, one pair of 45S rDNA site was detected on the centromeric region of chromosome 5. Whereas, two pair of 5S sites were detected on the short arm of chromosome 4 and centromeric region of chromosome 7, respectively. These are quite different patterns from A. membranaceus, A. membranaceus var. alpinus, and A. mongholicus. Although A. koraiensis is considered as Korean endemic species, therefore, it should be conducted out comparative FISH study with A. sikokianus and A. bhotanensis which are very similar to A. koraiensis morphologically.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.175-184
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• 2012

Changes of fish assemblage inhabiting around Dae Island in Gwangyang Bay, Korea were investigated using a small beam trawl monthly from March 2009 to February 2010. These data were compared with those obtained in previous studies(1990~1991 and 1995~1996) at our study sites. A total of 8,133 fish belonging to 74 species in 38 families were collected. Leiognathus nuchalis, Argyrosomus argentatus, Acentrogobius pellidebilis, Sillago japonica, Apogon lineatus, Thryssa hamiltoni, Repomucenus richardsonii, Pholis nebulosa, Pleuronichthys cornutus, Hexagrammos otakii, and Limanda yokohamae dominated, and these were responsible for 89.5% and 58.9% in the number of individuals and in biomass, respectively. These were primarily small species or early juveniles of larger species. Seasonal variation in both species composition and abundance was large: the peak number of fish species occurred in May and October 2009, whilst both number of individuals and biomass were the highest in May 2009. Fish numbers as well as biomass was lowest in January and February 2010. Seasonal changes in the abundance of fishes corresponded with temperature. Compared with the previous studies, the total number of individuals and biomass per unit area($m^2$) were higher, and the predominance of L. nuchalis occurred while abundances of Liparis tanakai were significant decreased. These results seemed to be change of species composition in fish assemblage which was due to variation of annual environmental characteristics in Gwangyang Bay.

• Korean Journal of Ichthyology
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• v.26 no.3
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• pp.212-221
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• 2014

Species composition and bimonthly changes of fish community were investigated with the fishes collected by using both trammel nets and fish pots in the coastal waters of Sagyeoi, Jeju Island from May 2009 to February 2010. A total of 1,921 individuals (324,206 g in biomass), which comprise 10 orders and 35 families with 60 species, were collected during the study period. Among 60 species, 52 species were caught by trammel nets, 20 species by fish pots, and 12 species by both fishing gears. The five dominant species were Pseudolabrus sieboldi, Plotosus lineatus, Pteragogus flagellifer, Sebastiscus marmorattus and Diodon holocanthus in the aspect of total number of individuals, and Diodon holocanthus, Sebastiscus marmorattus, Stephanolepis cirrhifer, Pseudolabrus sieboldi, Parupeneus chrysopleuron in biomass. Each characteristics of fish community such as the number of species, the total number of individuals, and biomass were highly correlated with water temperature and salinity, which were all statistically significant at the 5% significant level. In other words, there was a tendency of increment of each characteristics according to a raise in water temperature or a decrease of salinity, and vise versa. The number of species, the total number of individuals, and biomass of fishes were highest in August and lowest in February.

• Parasites, Hosts and Diseases
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• v.32 no.3
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• pp.163-170
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• 1994

An epidemiological survey was performed to know the infection status of heterophyid fluke metacercariae in the brackish water fishes purchased from a local market in Haenam-gun, Chollanam-do, Korea from November to December, 1991. A total 20 out of 30 shads (Konosiw punctatus) examined were infected with the metacercariae of H. continua (average number of larvae per an infected fish: 2.71). Of 20 perches (Lateolabroxjoponicurs), 19 were Infected with the metacercariae of H. continua (average number per an infected fish: 17.21. Of 30 mullets (Mugil cepholus) examined, 11 were Infected with the metacercariae of H. nocens (average number per an Infected fish: 51.5), 10 mullets harboured 31 and 349 metacercariae of f summa and 5. lucatum respectively. Of 30 gobies (Acnnthogobin jlcvimonus) examined, 3 were infEcted with the metacercariae of H. nucens (average number per an Infected fish: 32.0), 8 with those of H. continua (average number per an infected flesh: 12.6) and 3 with those of 5. JuscntuwL From the above results, It has been confirmed that the brackish water Ash from Haenam-gun, Chollanam-do are infected with numerous metacercarlae of H. nocens, H. continua, P. summo and S. fuscatum.