• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.15-27
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• 2024

The goal of this study was to provide basic data necessary for managing fish in the Seomgang River by confirming diversity of fish species in the Seomgang River and determining the degree of change in fish species through a comparison with earlier related work. Growth rate, obesity level, and temporal and spatial reproductive capacities were analyzed to determine growth characteristics of dominant species. Fish fauna and structure of the fish community were surveyed at three different time points from October of 2020 to August of 2021 at eight sites. In addition, growth characteristics of Zacco platypus from June of 2021 to July of 2022 at four sites were determined. A total of 3,999 individuals, 43 species, and ten families of fish were identified. Among these species, 19 (44.19%) were Korean endemic species and four (9.30%) were endangered species. The dominant species was Z. platypus. Pungtungia herzi was identified as a subdominant species. An analysis of length-weight relationships and condition factor (k) of Z. platypus confirmed a good state of growth. As a result of a frequency analysis of the total length, the life cycle of the Z. platypus population living in the Seomgang River was found to be stable. According to gonadosomatic index (GSI) analysis, the spawning season of Z. platypus was estimated to occur after May, consistent with the literature.

• 대한생식의학회:학술대회논문집
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• 2001.03a
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• pp.95-101
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• 2001

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.265-278
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• 2016

In this study, an ascending capability experiment was performed with largemouth bass and bluegill, which are exotic fish species inhabiting (the freshwaters) in Korea. The experiment was performed by dividing the subject fish into four groups according to their size and at four flow rates for each group. The number of fish passing through a reference line was analyzed by recording videos, and their swimming and ascending capabilities were observed by the naked eye. The number of fish passing through the reference line did not include those returning downstream within five minutes due to the high flow rate. The flow rate used for the analysis was the mean of the flow rate values measured at the left bank, the right bank, and in the middle of the stream. The results showed that the number of exotic fish migrating upstream decreased as the flow rate increased, regardless of the species and size of the fish. The comparison between the fish species showed that the ascending capability of bass was higher than that of bluegill, but the difference was not significant when considering the difference in the size of the fish. In addition, the upper limit flow velocity allowing the ascending of the exotic fish species was 1.11 m/s, when considering the fish returning to the downstream after the upstream migration and experimental error. The results of the experiment may be used as fundamental data for the blocking of fish and the management of exotic fish species by means of a high flow rate current. Further experiments, verification, and monitoring may need to be conducted continuously to determine whether the fish are able to pass through the reference line at a high flow rate, when they attain a high or cruising velocity. Additionally, the reaction of the fish species should be investigated by considering the response to external forces as well as pressure differences due to the flow rate.

• 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.

• FLOWER RESEARCH JOURNAL
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• v.26 no.4
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• pp.195-201
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• 2018

The plant morphological and chromosome characteristics of 'Bonanza', 'Coral Candy' and 'Purple Crystal', a formolongi-Asiatic (FA) interspecific hybrid species bred at the National Institute of Horticultural Science, Rural Development Administration (RDA), were investigated in this study. The flowering time of these species were found to have some variation. 'Bonanza' flowers in the middle to late June (medium-late maturing cultivar), 'Coral Candy' in the mid of June (medium maturing cultivar), and 'Purple Crystal' was observed to be in early June (early maturing cultivar). The flowering direction of all three cultivars are upward facing flowers and having a weak fragrance. The height of the plants was recorded in the range between 101.0 cm ('Purple Crystal') to 142.3 cm ('Bonanza'), thus they are able to develop cut flowers with excellent stem elongation. Flower diameters of 'Bonanza' (17.1 cm) and 'Coral Candy' (16.9 cm) were classified to be large sized flowers. On the other hand, 'Purple Crystal' had a narrow flower diameter (12.3 cm) with an outer petal width of more than 4.0 cm. Leaf length was observed for 'Bonanza' (15.7 cm), 'Coral Candy' (19.7 cm), and 'Purple Crystal' (11.1 cm). Chromosome analysis was done using FISH technique. Results revealed that all three cultivars were observed as triploids (2n=3x=36). FISH analysis also showed 5S/45S rDNA of 'Bonanza', 'Coral Candy' and 'Purple Crystal' as 4/11 loci, 4/12 loci, and 4/11 loci, respectively. The results of the FISH analysis are useful as markers to distinguish cultivars, since the patterns of rDNA observed on the remaining chromosomes are significantly different except FISH patterns of chromosome #3.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.146-159
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• 2020

The objective of our study was to analyze the distribution and composition of fish species and their community characteristics in agricultural waterways in the six water systems-Mankyung River, Seomjin River, Namhae Region, Tamjin River, Yeongsan River, and Dongjin River-during 2017-2018. Little is known about the distributions and community characteristics of the aquatic biota of agricultural waterways in Korea, even if the water bodies have important roles as spawning areas or habitats for fish. In this study, we identified 3,633 fish individuals in the waterways, belonging to 53 species, eleven families, and six orders (dominant species: Tanakia koreensis, T. lanceolate) and 7,108 fish individuals in the main rivers, belonging to 57 species, fifteen families, and nine orders. Moreover, three endangered wildlife (designated by the Ministry of Environment, Korea)-T. somjinensis, Acheilognathus majusculus and Coreoperca kawamebari-were found in the waterways. By fish guild analysis, we found that many waterways had a lower proportion of sensitive species and a higher proportion of omnivore species than those of the main rivers, which indicates a feature of a disturbed environment. In addition, by grouping with environmental variables, we found the group of waterways with high substrate complexity had a higher diversity index (Shannon index) and a lower dominance index (Simpson index) than that of simple substrate complexity. Overall, our study represents the characteristics of fish habitats in agricultural waterways and suggests the need to manage them and study further.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.384-389
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• 2021

This study was conducted on October 23, 2020 at the Cheongpyeong Reservoir located in Seorakmyeon, Gapyeong-gun, Gyeonggi-do, and analyzed the horizontal and vertical distribution patterns of fish based on data obtained using fishfinder. The total surface area of fishfinder survey conducted was 782,853 m², and where the water depth (WD) ranges from 10 m to 12 m is widest which 31.7% of total surface area. As a result of the heat map analysis, fish density was highest at right bank under the Gapyeong-bridge, but there was no specific pattern in horizontal distribution of fish. As a result of vertical distribution of fish analysis, 86.6% of fishes are observed at below 6 m of the fish depth (FD, distance from water surface to fish). As a result of the relative height (RH, water depth-distance from bottom to fish ratio) analysis, there was a tendency that fishes are distributed in near surface area more as the WD increased. This tendency could have various reasons such as water temperature gradient along the water depth, and further studies are required for detailed explanation.

• The Journal of Fisheries Business Administration
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• v.38 no.1 s.73
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• pp.19-45
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• 2007

There have not been many studies which considered both quantitative and qualitative location factors on the issues of site selection problems for a fish farm. This study develops AHP(analytic hierarchy process) model to resolve site selection problem for a fish raising farm by using quantitative and qualitative factors. In order to evaluate the validity of the location factors found in the literature review, the study used advice from fish raising farmers and related academic experts. Four major factors have been selected as economic factors, social factors, natural environmental factors and infrastructures. An AHP structural diagram has developed by considering the factors and potential sites proposed for fish farming. Through the survey on the preference of factors and potential sites, pairwise comparison matrices have been estimated and used to calculated the relative weights of each potential site. The AHP model process shown in the study can be applied to resolve site selection problems for fish raising farmers.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.652-655
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• 2001

In order to establish quality indices of commercial fish paste products, the contents of starch in fried fish meat pastes, crab meat analogs and steamed kamaboko were investigated, and significant correlation between starch and texture was also evaluated. from the results, the starch contents in fried fish meat pastes, crab meat analogs and steamed kamaboko were $16.5\sim20.6\%,\;12.4\sim17.3\%\;and\;8.1\sim8.7\%$, respectively. Two texture profiles such as hardness and elasticity had significantly correlation (p<0.01) with starch contents. Namely, the hardness had significantly positive correlation in fried fish meat pastes (r=0.78) and in crab meat analogs (r=0.71), respectively. Elasticity also had significantly negative correlation in fried fish meat pastes (r=-0.99).

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.69-81
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• 2010

This study was conducted at 25 sites of 6 mainstreams and 19 tributaries sites within Heuck Stream watershed during May~October 2003 for the survey of fish distributions, compositions, and community characteristics. The survey showed that total fish was identified as 9 family and 26 species in all sites, and Cyprinidae dominated the community as 15 species. The dominant species of >20% of the total were Zacco temminckii (29%), Zacco platypus (22%), and Rhynchocypris oxycephalus (21%) in the watershed. Community analysis, based on the stream spatial gradients, indicated composition differences along the main axis of the stream from the headwater to the downstream; R. oxycephalus predominated in the most headwater zone and Z. temminckii dominated in the lower headwater zone, whereas Z. temminckii -Z. platypus dominated in the mid-to-downstream, and Z. platypus dominated the community in the most downstream zone. Total endemic species was 7 family and 15 species, which is made of 50% in the fish community, so that the high proportion of endemic species indicated a healthy region in terms of fish community, compared to average 23% in Korean peninsula in general. The total number and species of fish increased as the stream order (stream size) increased, indicating that impacts on chemical pollution or habitat disturbance were not so large to the fish community in this watershed. Trophic and tolerance guilds analysis showed that relative proportions of sensitive and insectivore species were >50% in the watershed and decreased as the stream order increased, whereas relative proportions of tolerant and omnivore species showed an opposite results. These outcomes suggest that the natural condition of watershed is preserved relatively and the region should be protected from the chemical and habitat disturbace by agricultural activity and urban developments.