• Journal of environmental and Sanitary engineering
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• v.21 no.2 s.60
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• pp.20-29
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• 2006

Analysis of benthic macroinvertebrate community and biological estimation of water quality by the benthic macroinvertebrates were conducted at Olympic Park at its nearby waters in Seoul from December, 2004 to September, 2005. The benthic macrovertebrates were 49 species. Among them, 39 species of aquatic insects were included 11 species in odonata, 9 species in diptera, 7 species in hemiptera, 6 species in coleoptera, 3 species in ephemeroptera, 2 species in trichoptera and 1 species in lepipdoptera, and 10 species of non-insects were 6 species in mollusca, 2 species in hirudinea and 2 species in oligochaeta. Species number of lakes, Seongnae Stream within and outside the Olympic Park was 25 species, 35 species and 33 species, respectively. Individual number of lakes, Seongnae Stream within and outside the Olympic Park was $131\;inds/2.5m^2\;239\;inds/2.5m^2\;556\;inds/2.5m^2$, respectively. Mean dominance indices of lakes, Seongnae Stream within and outside the Olympic Park was 0.74, 0.61 and 0.72, respectively. According to the saprobic system based on the ESB index(Ecological score of benthic macroinvertebrate community), all survey sites are $\beta-mesosaprobic$ waters. To increase of abundance of benthic macroinvertebrates, regular interval monitoring has to be enforced and standard of water quality for the ecological ponds of Olympic Park has to be prepared.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2008.04a
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• pp.40-41
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• 2008

• Animal cells and systems
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• v.7 no.4
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• pp.331-335
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• 2003

Vertebrates with different habitats have different proportions of visual cells, with the rod cells responding to scotopic vision and the cone cells responding to photopic and color vision in their retinas. The present work studied whether the kinds and arrangement patterns of the cone cells and interlocking morphology of the lens were related to the kind of preys and habitats in the genus Zacco. The retinas were observed by a light microscopy using H-E staining method and the interlocking formula of the lens fibers were investigated by a scanning electron microscopy. The interlocking formula of the lens fibers of Z. temmincki is an ' anchor and socket ' connection, and that of Z. platypus is a ' ball and socket ' connection. The cone cells of Z. platypus and Z. temmincki constituted compacted mosaic patterns of row type. Away from the center, the double and single cone cells gradually increased in diameter. Zacco temmincki had identical double cone cells and Z. platypus had non-identical double and single cone cells. The eyes of Z. temminckifeeding on a moving aquatic insects in relative limpid water and swift current of mid and upper stream have better resolution than that of Z. platypus feeding on mainly adhesive algae and some aquatic insects in slightly turbid water of mid stream.

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.223-229
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• 2015

Pre-monsoon dynamics of zooplankton community were investigated in the downstream of the Gagok stream flowing into the East Sea of Korea. Monthly sampling was carried out to collect zooplankters at five sites in the stream during the period between April and July 2014. Dissolved oxygen contents exceeded $7.0mg\;L^{-1}$ all the time. Water temperature was in a range of 15.7 to $24.9^{\circ}C$ and pH 7.4 to 8.8, respectively. A total of 75 taxa consisted of 36 species of rotifers, 16 species of cladocerans, 16 species of copepods, four kinds of aquatic insects, two kinds of decapods and one nematod was occurred. One species of marine copepod and one cladoceran, and one species of brackish rotifer and one copepod distributed at the station located in the stream mouth. Zooplankton abundance showed to vary from 42 to 4202 individuals $m^{-3}$ due to the explosion of aquatic insects and Alona sp. at site 2 located in the downstream in April. Heavy rainfall during the monsoon period seems to decrease the zooplankton abundance caused by diffusion and drifting to the sea. Species diversity indices were generally high between 1.2~2.3 and were recorded to be high at the downstream throughout the study period. With the zooplankton dynamics, the influence of the input of sea waters into the stream seemed to be confined to some hundred meters of the stream mouth facing the East Sea.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.279-284
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• 2008

The feeding ecology of endangered Cottus hangiongensis was studied in the Hosan stream from September 2006 to August 2007 by collecting them seasonally. The stomach contents of C. hangiongensis consisted mainly of aquatic insects and Nematoda, small fish, fish eggs, snails (Semisulcospira libertina), and small stones were also observed. The main aquatic insects in the order of relative importance were Diptera, Trichoptera, Ephemeroptera and Plecoptera. The most important prey items were Chironomidae sp.1 and Hydropsyche kozhantschikovi. Change in the main prey organisms by season were Trichoptera in the spring and the summer, Diptera in the autumn, and Plecoptera in the winter by ratio of dry weight.

• Journal of Wetlands Research
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• v.12 no.2
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• pp.35-46
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• 2010

This study was conducted for searching the fauna, altitudinal distribution, and food patterns of the aquatic insects on Jeju island. The samples were collected from 102 freshwater wetlands during 2004 to 2008. The identified species were 100 belonged to 73 genera, 32 families, and 7 orders. One species of the genus Ephemeroptera, 23 of the Odonata, 1 of the Plecoptera, 23 of the Hemiptera, 47 of the Coleoptera, 3 of the Trichoptera, and 2 of the Diptera were identified in this study. The most widely distributed species was Sigara substriata, which was followed by Crocothemis servilia, Orthetrum albistylum, Gerris latiabdominis, and Anisops ogasawarensis. Sixteen species including Gynacantha japonica were very restrictedly distributed, which were sampled from only one site, respectively. The restrictedly distributed species (R) were classified into three altitudinal ranges, low (L), middle (M), and high (H). Ten species including Ranatra unicolor were RL type, only one species, Berosus japonicus, was RM, and 6 species including Nemoura KUb were RH. Narrowly distributed species (N) were 44 including Lethocerus deyrollei and intermediately distributed species (I) were 18 including Hesperocorixa distanti, and widely distributed species (W) were 21 including Nepa hoffmanni. According food uptake patterns, 75 species were carnivores, 18 herbivores, 5 omnivores, and 2 detritivores. Especially almost W were carnivores. From these results, we could concluded that the most aquatic insects species of Jeju island were characterized by their very limited altitudinal distribution range and carnivorous preference.

• Korean Journal of Agricultural Science
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• v.50 no.2
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• pp.257-270
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• 2023

The paddy environment is classified as a wetland and occupies a very large proportion of the freshwater environment. It is also ecologically important as a habitat and spawning ground for many aquatic insects and amphibian larvae. However, due to climate change and indiscriminate spraying of pesticides, the rice field ecosystem is continuously threatened. In order to restore ecologically damaged rice paddies in the future, information on organisms living in the rice paddy ecosystem, which can serve as a restoration standard, is needed. The eDNA metabarcoding analysis method is a very effective means of accumulating information on many organisms living in the rice field ecosystem because it can indirectly identify the existence of taxa that are no longer found in the target ecosystem due to different adult life periods or metamorphosis. In this study, genes of four species of frogs and nine species of aquatic insects were also discovered, and some taxa were directly discovered in the field. A large number of taxa have been discovered only by DNA searches, and traditional survey methods have only been able to identify very limited taxa. This eDNA-based paddy field biosearch is expected to be very useful in the investigation of biodiversity in agricultural ecosystems due to its strong analytical resolution.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.3
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• pp.177-194
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• 2011

In order to assess ecologically for the restored detention basin in Joogyo creek, this study carried out a monitoring on the ecosystem of the detention basin. The study site was a small detention basin with an area $6,350m^2$, which had been established in March, 2004. The monitoring started in August and November, 2007. Terrestrial, riparian, and aquatic plants species have increased about 2 times at detention basin compared to that of streamside. Mammals, birds, reptiles, amphibians, aquatic insects and crustaceans were found more in species at detention basin, and especially there were a lot of more fish species. From the results, it seemed that various terrestrial, riparian, and aquatic ecosystem were made in the small detention basin.

• Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.344-354
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• 2023

Food and feeding habits of large cyprinid fishes (Labeobarbus intermedius, Labeobarbus nedgia, and Labeo forskalii) had been investigated in the upper Blue Nile River, Ethiopia. Four sampling sites were selected and specimens were sampled during the post-rainy (November 2016) and dry (March 2017) seasons by gillnets of 6 cm, 8 cm, 10 cm, 12 cm, and 14 cm mesh sizes. Totally 401 fishes were collected and about 30.4% (122) of the samples were documented with empty guts and 279 (69.6%) of them were with non-empty guts. The whole contents of all non-empty gut specimens were taken, labeled, and preserved using a 5% formaldehyde solution for further analysis. In the laboratory, gut contents were examined and identified using compound and stereo microscopes. The relative importance of different food items in the diet compositions was analyzed using a frequency of occurrence and volumetric analysis. During the post-rainy season, insects and phytoplankton were mostly ingested as food items. However, during the dry season, phytoplankton was the most important food item in the diet of all cyprinid fishes of the river. Based on current study results, L. intermedius and L. nedgia might be omnivores in their diet but Labeobarbus forskalii seemed to be detritivorous.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.75-80
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• 1998

Organically cultured rice fields were surveyed to compare the population density and the structure of microarthropod communities between chemically controlled and un-controlled fields. In rice fields, microarthropod communities were also compared among four treatments based on different input of fertilzer : 1)No fertilizer, 2)Chemical fertilizer(N-P2O5-K2O = 11 - 7 - 8 kg/10a, 3) Compost (5,000kg/10a), 4) Compost com-plemented with chemical N. Richness index of microarthropod communities in rice fields was greater in the chemically uncontrolled field than controlled field. Within field. the compost plot had greater value of richness index for microarthopod commuities than the non-fertilizer polt. A total of 9 aquatic insects species were identified in the water of organic farming rice field the population density was found to be higher in the compost plot than the other plot. The population of insect pests was found to be high in the late stage of plant whereas the population of insects was high in the early stage of rice plant.