• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.48-55
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• 2012

Egg development and early life history of the slender shinner, $Pseudopungtungia$ $tenuicorpa$ were investigated to provide basic information regarding biological characteristics and restoration in 2010. Eggs were obtained by injecting females with Ovaprim and then fertilized using the dry method in the laboratory. Matured eggs were strongly adhesive, opaque and grayish and measured $1.96{\pm}0.08mm$(mean${\pm}$SD) in diameter. Fertilized eggs hatched 240 h after fertilization at $23^{\circ}C$, and newly hatched larvae an average $8.6{\pm}0.25mm$ in total length. At 2 days after hatching, larvae averaged $9.0{\pm}0.37mm$ in total length and their yolk sacs had been completely absorbed. About at 10 days after hatching, they beacme to juvenile stage and reached $10.6{\pm}0.44mm$ in total length. At 70 days after hatching, the band patterns and external form of juveniles were similar to those of adults, and they averaged $36.0{\pm}2.13mm$ in total length.

• Korean Journal of Ichthyology
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• v.29 no.4
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• pp.235-243
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• 2017

Reproductive characteristics of Rhodeus pseudosericeus (Pisces: Acheilognathinae) was investigated at the Heukcheon (River), Yangpyeong-gun, Gyeonggi-do, Korea from January to July in 2012. This fish prefers heavily vegetated stagnant pool with Phragmites japonica and Salix koreensis and area with high proportions of sand and mud. The standard length of the population indicated that 13~22 mm group is 0-year old, 30~45 mm group is 1-year old, 45~55 mm group is 2-year old and 45~70 mm group is more than 3-year old (June in 2012). The sex ratio of female to male was 1 : 0.80. The spawning season was from March to June with water temperatures in the range $11.0{\sim}26.2^{\circ}C$. The embryos were found with no egg mass in Unio douglasiae sinuolatus and the number of those was 1~22 ($5.8{\pm}5.51$). The number of the embryos found in each of the four parts of the mussel gill was 1~9 ($2.7{\pm}2.16$) in left outer, 1~2 ($1.5{\pm}0.71$) in left outer, 1~5 ($1.8{\pm}1.79$) in left outer and 1~22 ($5.8{\pm}5.51$) in left outer.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.335-352
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• 2014

In this study, we investigated and analysed the water quality, distribution of the vegetation and the wildlife to seven wetlands in Donghae city. As a result, most of the wetlands was found to be very poor water quality and some specific pollutants from entering the wetland. A total of 234 taxa on vegetation were identified including 207 species, 24 varieties, 3 formaes, 168 genera and 69 families. 2 species were recorded as designated rare plant of Korea Forest Service. The naturalized plants were 27 species. The urbanization rate of naturalization index was 8.4% and 11.6% respectively. The number of benthic macroinvertebrate taxa was 35 species, 26 families, 12 orders, 5 classes and 3 phylums. Rare species were recorded 3 species. Taxa for fishes were 5 family and 5 species. Endangered wildlife was found 1 species. Most wetlands in Donghae city were the relatively small in size, and some wetlands were separately located from forest and river ecosystems. It was limited inflow and outflow of species into a wetland from the outside. However, various vegetation were found at whole wetlands and some special species also inhabited. The wetlands performed the role as a habitat of wild life.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.181-189
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• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.100-115
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• 2014

For this study, we collected fishes of seven times at the 51 sites by stream orders (2-6) from November 2007 to September 2010. In the results, 55 species belonging 12 families were collected. And there were one species (1.8%) of Natural monument, 6 species (10.9%) of endangered and 22 species (40.0%) of Korea endemic. Dominant species was Zacco koreanus and subdominant species was Zacco platypus in whole. Stream orders (2-6) increased with increasing species, diversity (H'), evenness (EI), richness (RI), tolerant (TS), omnivore (OS) and decreasing individual, dominance (DI), sensitive (SS) insectivore (IS), total IBI score. Principal component analysis results showed location of variable (species, individual, community index, relative abundance of tolerant, sensitive, omnivore, insectivore species) and each site changes in upstream and down-stream changes in their distribution. Correlation analysis showed significant differences between stream orders (2-6) and variable (species: Sp, diversity index: H', omnivore species: OS, stream depth: SD, stream width: SW and water temperature: WT).

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.352-358
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• 2018

This study aimed to develop a species identification method for the egg and fry of the three Korean bitterling fishes (Pisces: Acheilognathinae), including Acheilognathus signifer, Acheilognathus yamatsutae and Rhodeus uyekii based on the PCR-based Restriction Fragment Length Polymorphism (RFLP) markers. We conducted a field survey on the Deokchicheon River from the North Han River basin, where the three Acheilognathinae species co-occur, and also analyzed the existing sequence dataset available from the GenBank. We found coexistence of the three species at the study site. The egg and fry were obtained from the host mussels (Unio douglasiae sinuolatus) by hand from May to June 2015 and in May 2017. To develop PCR-based RFLP markers for species identification of the three Acheilognathinae fish species, restriction enzymes pinpointing species-specific single nucleotide variation (SNV) sites in mitochondrial DNA COI (cytochrome oxidase I) and cyt b (cytochrome b) genes were determined. Genomic DNA was extracted from the egg and fry and RFLP experiments were carried out using restriction enzymes Apal I, Stu I and EcoR V for A. signifer, A. yamatsutae and R. uyekii, respectively. Consequently, unambiguous discrimination of the three species was possible, as could be seen in DNA band patterns from gel electrophoresis. Our developed PCR-based RFLP markers will be useful for the determination of the three species for the young and would assist in studying the spawning patterns and reproductive ecology of Acheilognathinae fishes. Furthermore, we believe the obtained information will be of importance for future maintenance, management and conservation of these natural and endangered species.

• Korean Journal of Ichthyology
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• v.33 no.4
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• pp.217-225
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• 2021

The family Platycephalidae is a taxonomic group of economically important demersal flathead fishes that predominantly occupy tropical or temperate estuaries and coastal environments of the Indo-Pacific oceans and the Mediterranean Sea. In this study, we for the first time analyzed the complete mitochondrial genome (mitogenome) of the flathead Platycephalus cultellatus Richardson, 1846 from Vietnam by Next Generation Sequencing method. Its mitogenome was 16,641 bp in total length, comprising 13 protein-coding genes (PCGs), two ribosomal RNA genes, and 22 transfer RNA genes. The gene composition and order of the mitogenome were identical to those of typical vertebrates. The phylogenetic trees were reconstructed based on the concatenated nucleotide sequence matrix of 13 PCGs and the partial sequence of a DNA barcoding marker, cox1 in order to determine its molecular phylogenetic position among the order Scorpaeniformes. The phylogenetic result revealed that P. cultellatus formed a monophyletic group with species belonging to the same family and consistently clustered with one nominal species, P. indicus, and two Platycephalus sp. specimens. Besides, the cox1 tree confirmed the taxonomic validity of our specimen by forming a monophyletic clade with its conspecific specimens. The mitogenome of P. cultellatus analyzed in this study will contribute valuable information for further study on taxonomy and phylogeny of flatheads.

• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.553-562
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• 2023

The Gobiobotia naktongensis is a species endemic to Korea, and it has recently been designated as a class I endangered species of freshwater fish. Naeseong Stream, one of the tributaries of the Nakdong River, where the Gobiobotia naktongensis was first discovered, provided an optimal habitat for the Gobiobotia naktongensis in the past with fine sand beds and riffle. Currently, due to the construction of Yeongju Dam and the excessive dredging of river channels by the local government, the riverbed armoring in the downstream area of the dam is undergoing rapid changes, and as a result, the habitat environment of the Gobiobotia naktongensis is deteriorating. In this study, the variations of the habitat suitability of the Gobiobotia naktongensis due to the change in the riverbed grain size of the Naeseong Stream were analyzed based on the WUA (weight usable area) using the physical habitat model, River2D. The study domain is the reach from Seoktap Bridge to Hoeryong Bridge downstream of Yeongju Dam. The change in riverbed grain size was analyzed using D50 acquired in 2010 and 2020, respectively. The substrate grain size of Naeseong Stream in 2020 was thicker than that in 2010, and the riverbed coarsening phenomenon was evident overall. As a result of the River2D analysis, the area in which the Gobiobotia naktongensis could inhabit was only about 0.75% in 2010 compared to the entire area of the flow, and even this decreased to 0.55% in 2020 due to riverbed armoring.

• Korean Journal of Ichthyology
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• v.23 no.4
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• pp.288-299
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• 2011

Freshwater fish fauna and community structure were surveyed through 21 lakes in the Yeungnam area including Gyeongsangbukdo and Gyeongsangnamdo provinces, Korean Peninsula from April 2008 to October 2009. Among 21 lakes, 16 lakes belong to the Nakdong River and 5 are independent drainages. From the present study, 61 species (44 genera, 15 families) were collected including 32 cyprinid species (52.5%), 6 cobitid species (9.8%) and so on. The dominant and subdominant species in aspect of the number of individuals were Hypomesus nipponensis (26.6%) and Squalidus gracilis majimae (14.8%), respectively. On the other hand, in aspect of in biomass, dominant and subdominant species were Lepomis macrochirus (19.8%) and Cyprinus carpio (14.7%), respectively. Among 61 examined species, there were found 20 Korean endemic species and 2 Korean endangered species (Pseudobagrus brevicorpus and Pungitius kaibarae). P. brevicorpus was found in Yongyeonji and Yeongcheonho, and P. kaibarae in Yongyeonji. In addition, 5 exotic species were identified such as Cyprinus carpio nudus (leather carp), Carassius cuvieri, Hypophthalmichthys molitrix, Lepomis macrochirus and Micropterus salmoides. Interestingly, a bluegill L. machrochirus appeared dominant or subdominant species in 5 of 21 examined lakes. Five species introduced from the other rivers in Korean Peninsula were additionally described. In the present study, it was first reported that Micropercops swinhonis inhabits in the Nakdong river basin. The fish species diversity, evenness and dominant indices were examined, and a dendrogram based on similarity indices of inhabiting species among the 21 examined lakes was constructed and discussed.