• The Korean Journal of Zoology
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• v.31 no.1
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• pp.56-61
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• 1988

The taxonomic status of Moroco Jagowskii and M oxycephalus a pair of sibling species inhabiting in Korean fresh waters, has been unclear up to date. Recently a sympatric area of these species was found (Kang, 1987). The purpose of this study was to clarify their specific status by analysing specimens collected from the sympatric area of these species. Isozyme analysis and morphometric comparison were performed. Among 26 loci screened 6 loci (Aco, Est-2, E-X, Gk-3, Ipo, Me) showed fixed allelic difference between them and these loci could be used as genetic markers to distinguish them. Isozyme analysis indicates that no hybridization occurs and therefore it is assumed that isolating mechanism is completed and they are distinct species. The mean number of scales above lateral line (SAL) of M Jagowskii and M oxycephalus at sympatric area was 24.93 $\pm$1.95 and 17.33$\pm$0.72 respectively, and it seems as the result of character displacement. A finer microhabitat segregation between them is noticed. M oxycephalus is found along the effluent streams whereas M lagowskii is distributed mostly in the main stream at sympatric area.

• Journal of fish pathology
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• v.34 no.1
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• pp.55-61
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• 2021

One of the major problems in fish production is that parasite-induced episodes of disease can result in significant impacts to the health of stock, mortalities and, economical losses. Seabreams are economically important fish in both the capture fishery and aquaculture sectors in Oman and represent potential species for aquaculture. The current study set out to investigate infection of polyopisthocotylean monogeneans on the gills of wild goldlined seabream, Rhabdosargus sarba, caught from Musairah region in Oman. The prevalence, mean intensity and abundance of polyopisthocotyleans on 145 fish was found to be 52.41%, 5.65 and 3.04, respectively. Three species of microcotylid parasite were isolated, one being Atrispinum acarne while the remaining two species require further study to identify them. There was no significant difference in the infection rate between host sex, however, parasite burdens were higher on larger sized fish (p<0.05) and were found to favour the first gill arch (p< 0.05). The study found that the sample of Rhabdosargus sarba landed in the waters around Musairah are heavily infected, with a predominantly immature population of microcotylids. Further work is required to better understand the potential risk each species poses to the health of its host before a decision is made on the suitability of new candidate fish species for commercial aquaculture.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2B
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• pp.153-160
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• 2006

To recommend ecological flow for major tributaries in Han River basin, the Instream Flow Incremental Methodology (IFIM) have been applied. In particular physical habitat simulation using PHABSIM have been selected for microhabitat variables and QUAL2E model have been used to implement macrohabitat simulation. Habitat Suitability Criteria (HSC) for different life stages in accordance with different hydraulic variables (depth and velocity) have been presented by the field surveying data. We review IFIM procedures and discuss limitations of habitat simulation with specific reference to Han River basin. The results of this research can be used as reference flow for estimation of instream flow in Han River.

• Korean Journal of Ecology and Environment
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• v.54 no.1
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• pp.24-38
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• 2021

Microhabitat In the upper stream is created by various environment variables such as the bottom substrate and the physicochemical factors, and may influence the distribution of benthic macroinvertebrates. We investigated the bottom substrate and environmental variables influencing the distribution of benthic macroinvertebrate in 26 stream-type waterways established at upper reaches of Geum River. During study period, total 85 families, 160 species, 9305 individuals of benthic macroinvertebrates were recorded. The stream-type waterways, where the bottom substrates consist mainly of pebble (16~64 mm) and cobble (64~256 mm) or with rapid water velocity (more than 0.2 m/s) and high dissolved oxygen (more than 120%), were supported by high species diversity of benthic macroinvertebrate. Hierological cluster analysis and the nonparametric multidimensional scale (NMDS) divided 26 stream-type waterways into a total of three clusters. In Cluster 1, the invertebrate species, such as Branchiura sowerbyi, Cloeon dipterum, Ischnura asiatica, Paracercion calamorum, and Radix auricularia, closely related to aquatic macrophytes, and Chironomidae spp., Limnodrilus gotoi, and Tanypodinae sp. were abundant in waterways, with high coverage of silt and clay as well as high turbidity and total nitrogen. The benthic macroinvertebrate species (Cheumatopsyche brevilineata, Drunella ishiyamana, Dugesia japonica, Ephemera orientalis, Gumaga KUa, Macrostemum radiatum, Potamanthus formosus, Semisulcospira libertine, Stenelmis vulgaris, and Teloganopsis punctisetae) included in Cluster 2 were dominated in sites with high cover rates of pebble and gravel. Cluster 3 was predominantly covered by the Cobbles, was supported by Simulium sp. Such a clear distinction in the study sites means that each stream-type waterways is governed by a clear habitat environment. In the case of some sites with low species diversity, improvement measures are required to restore nature, such as improving the function of inflows and outflows, creating meandering channel, and inducing the settlement of littoral vegetation.

• Journal of Popular Narrative
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• v.25 no.1
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• pp.55-85
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• 2019

In this article, we examine the real meaning behind the stories in which the N-po Generation (Millennial Generation) is depicted, through the observation of entertainment programs, TV series, and movies. This could be an opportunity to investigate the aspects of emotional customs of our era, which have been described by television media as portraying the complex and multifaceted reality in the most mundane and popular manner while influencing the public. Problems with youth unemployment, the polarization of life, and instability are not only global issues but situations that specifically occur in South Korea. It is thus vital to pay attention to the inner side of the N-po Generation who enjoy Sohwakhaeng (small but certain happiness) by eating alone as the placebo effect of this tough reality. This is an agenda that should be viewed as a problem in the fundamental design of South Korean society. The consciousness of the problem shown in the TV series has been drawing attention. The TV series Because depicts a love narrative that concentrates on emotions in a relationship that started between housemates due to poverty and housing problems, leading to marriage. Thus, the TV series persuasively dramatized 'confluent love' in the N-po Generation. In the movie , Miso can be regarded as a symbol that represents the emergence of a new generation of cultural sensitivity. There is a suggestion in the sequence of that identifies the pursuit of taste with the discovery of identity. The TV series is a growth narrative that deals heavily with youth unemployment, temporary workers, fragmented families, and dating violence. The housemates in find emotional stability through interaction with each other, and courageously approach their individual problems. In the process, images of women, who are empathetic towards others and are willing to jointly solve their problems, are calmly depicted to reveal a story of growth revolving around a ground emotional community. The current problem that South Korean society should contemplate is how to be fully human beyond mere survival, and how to further seek the conditions of human existence. In that sense, what we should pursue is a notion of 'publicness', which can put several generations together. Because of the reality that confliction between generations must be triggered, in order to make a passage of sympathizing, mass media's sensitivity training becomes more important. This may be the duty of mass media.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.334-343
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• 2014

BACKGROUND: Shorebirds use a variety of wetlands as their stopover sites to replenish energy and nutrient reserves along the migration route. It is increasingly important to understand how birds use the remaining available habitats during migration period, because shorebird stopover sites are often altered and destroyed. Rice fields serve as a major inland stopover site for migrating shorebirds. However, the information on habitat use patterns of shorebirds in rice fields is very limited in Korea. Therefore, we studied the patterns of shorebird abundance and their habitat use in rice fields during spring migration period in western-central Korea. METHODS AND RESULTS: Surveys were conducted at interval of 2-3 days during the spring migration period of 2014 at rice fields of mid-western Korea. We recorded the location of the observed birds on the rice field map according to the local habitat type. The habitat types were divided by physical structure and cultivation methods. Fifteen shorebird species and 7,852 individuals were recorded during the survey period. The number of shorebird species and their abundance began to increase from the beginning of flooding in late-April, and reached a maximum in early-May. After rice transplantation, the number of shorebird species and their abundance dramatically declined. Shorebirds selectively used paddy and levee rather than road and ditch and most species used shallow depth field type. Plowed field types were less attractive to most species. CONCLUSION: Flooding rice fields were functioned as stopover sites for a variety of shorebird species during spring migration period. Furthermore, these results provide that the appropriate agricultural practices can be improving the habitat quality for shorebirds.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.40-54
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• 2017

The mound grave of Korean traditional funeral culture is a unique habitat which is a Zoysiagrass lawn being sustainable in proper management. We phytosociologically described an unusual Zoysiagrass vegetation with Gueldenstaedtia verna by the Zürich-Montpellier School's method and analyzed eco-floristic characteristics. A new association, Gueldenstaedtio-Zoysietum japonicae ass. nov. hoc loco, was identified and subdivided into festucetosum ovinae, typicum, and trifolietosum repensae. The subassociations were distinguished by the difference in species composition resulting from site accessibility and lawn management method. The association was assigned as not only a regional but also a locally-limited vegetation type, which distributes on a particular microhabitat with strong continentality in the Daegu regional subdistrict of Bioclimatological division. The Zoysiagrass vegetation of Korea was considered as a continental type apparently different from the oceanic type of Zoysion japonicae (Miscanthetea sinensis, Caricetalia nervatae). Mound graves in Korea should be acknowledged as a meaningful habitat for the in-situ conservation of biodiversity and phytocoenosen, despite being a secondary grassland of Gueldenstaedtio-Zoysietum japonicae.

• Korean Journal of Ecology and Environment
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• v.46 no.1
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• pp.86-93
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• 2013

We monitored 32 wetlands in order to investigate the influence of aquatic plants on zooplankton density and diversity in the littoral zone in Gyeongsangnam-do from May to June in 2011. A total of 65 zooplankton species were identified in the study sites. Among them, the diversity of epiphytic zooplankton were higher (40 species) than planktonic zooplankton. Littoral zones of all wetlands were covered by various aquatic plants, and influenced the epiphytic zooplankton assemblages. Based on the data from $1{\times}1$ (m) quadrat sampling, epiphytic and planktonic rotifer density showed no significant relationships with macrophyte cover. However, the epiphytic cladocerans density significantly increased under high aquatic plant cover ($r^2=0.39$, p<0.05, n=32). Types of aquatic plants strongly influenced epiphytic zooplankton density. Upo and Jangcheok are locations which have well developed Phragmites communis and Ceratophyllum demersum communities in the littoral zone, and a higher density of epiphytic zooplankton was recorded on the surface of C. demersum. Especially, rotifers such as Lepadella, Monostyla and Testudinella showed obvious differences (One-way ANOVA, p<0.05 for all three species). This result suggests that epiphytic zooplankton have a substrate preference for larger surface areas, likely for adherence, on C. dimersum. In conclusion, the complex structure of the littoral plant community is expected to provide diverse refuge and microhabitats to epiphytic zooplankton.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.11-20
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• 1988

A comparison between two species of Hyla japonica and H. suweonesis in Korea was carried out to clarify their morphological, genetic and ecological differences, to estimate presumed divergent time between them, and to elucidate their probable process and mechanism of speciation. The results are as follows; 1.The breeding season of H. japonica was earlier than that of H. suweonensis about one and half months. 2.H.japonica was distributed all over the country, while H. suweonensis was restricted in Kyonggi plains. 3.On the extemal morphometric characters, differences were hardiy seen between two species. But on the discriminant function analysis, there was apparent differences between them. 4.Genic variation based on 24 loci showed that H. japonica populations were about two fold more variable than that of H. suweonensis populations. 5.Genetic relatedness between two species was rather remote (S =0.520, D=0.634) 6.Their presumed divergent time was estimated to be about three and a quarter mfllon years. It is presumed that H. suweonensis was originated from H. japonica during the period of late pleocene and early pleistocene. 7.Premating isolating mechanisrns (breeding season, mating call, and microhabitat segregation) may be operating to prevent gene ifow between them.

• Korean Journal of Environment and Ecology
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• v.22 no.1
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• pp.35-42
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• 2008

This study was conducted to provide basic information that can be used to restore habitats of Nannophya pygmaea. Nannophya pygmaea is an endangered species of wildlife fauna in Korea and its habitats are distributed very scarcely in Korea. Ten wetland sites throughout Korea, where N. pygmaea inhabited (2 sites in Incheon Muui-do, 1 site in Gokseong Singi-ri, 4 sites in Gokseong Wolbong-ri, and 3 sites in Mungyeong Yulsu-ri) were investigated from June 2006 to August 2007. Investigation was made on landscape properties, habitat sizes, vegetation types, water environments, and water sources. N. pygmaea was generally found in the abandoned paddy fields surrounded by mountains. The habitats ranged from $113.4m^2$ to $1,153.1m^2$ in area, and were mostly dominated by Juncus effusus and Persicaria thunbergii. The water level was $2.6\sim7.3cm$, and the water temperature ranged from $16^{\circ}C$ to $27.8^{\circ}C$. The elevation of the habitats ranged from 139 to 243 m above sea level, which was mostly lower than that of other high mountain wetland habitats. In conclusion, the habitats of N. pygmaea can be restored at wetlands, which have similar condition with field habitat such as abandoned paddy fields in the beginning stage of oligotrophy. Because N. pygmaea is sensitive to microtopography and other surrounding environments, the approach to restore the habitats for N. pygmaea should consider those microhabitat conditions shown in this study.