• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.44-44
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• 2004

• 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.

• Fisheries and Aquatic Sciences
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• v.21 no.8
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• pp.28.1-28.12
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• 2018

Intertidal macroalgae are exposed to many abiotic stress factors, and they must regularly react to changes in their environment. We used RNA-seq to describe how Porphyra umbilicalis (Rhodophyta) changes gene expression patterns to interact with different habitats. Tissue samples were taken from a typical habitat along the open-coast of the Northwest Atlantic, as well as from a rare, atypical habitat in an estuarine tidal rapid environment. Differential gene expression analyses suggest that pathogic bacteria and viruses may be a significant factor influencing the transcriptome in the human-impacted estuarine environment, but the atypical habitat does not necessarily induce more stress in Porphyra umbilicalis growing there. We found genes related to nitrogen transport are over-expressed in tissue from the open-coastal site compared to those from the estuarine site, where environmental N levels approach hypertrophic levels. Low N levels impede growth, but high levels are toxic to cells, and we use qPCR to show this species regulates expression of a putative high-affinity $NH_4{^+}$ transporter under low and high N conditions. Differences in expression of this transporter in these habitats appear to be inherited from parent to offspring and have general implications for adaptation to habitat in other species that are capable of asexual reproduction, as well as more specific implications for this species' use in aquaculture.

• The Korean Journal of Mycology
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• v.21 no.2
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• pp.127-132
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• 1993

269 yeast strains were isolated from water samples collected from different sites in Minia governorate. These included 126 strains from fresh water, 108 strains from sewage and 35 strains from wastewater from sugar-cane factory. On the basis of 23 different physiological and morphological merkmals, the isolated strains were assigned to 16 species belonging to 11 genera. Total yeast cell counts as well as spectra of yeast species were highly variable in tested water. Total yeast cell counts ranged between $3.0{\times}10^3/l\;and\;1.8{\times}10^6/l$ for fresh water, $3.0{\times}10^4/l\;and\;3.0{\times}10^7/l$ for sewage and $1.5{\times}10^6/l\;and\;2.6{\times}10^7/l$ for wastewater from sugarcane factory. Debaryomyces hansenii, Rhodotorula mucilaginosa and Torulaspora delbrueckii were the dominant species in fresh water, whereas Debaryomyces hansenii, Thrichosporon beigelii, Rhodoforula mucilaginosa and Kluyveromyces marxianus were the dominant species in sewage and Saccharomyces cerevisiae, Kluyveromyces marxianus and Trichosporon beigelii were the dominant species in wastewater from sugar-cane factory. Yeast human pathogens, Trichosporon beigelii, Rhodotorula mucilaginosa and Candida albicans were encountered in water samples indicating that water in El-Minia governorate is also polluted by some pathogenic yeasts.

• Journal of People, Plants, and Environment
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• v.24 no.5
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• pp.469-483
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• 2021

Background and objective: If the Nelumbo nucifera spreads in a wetland at a high density, it can have considerable positive and negative ecological effects on habitats. For this reason, it is necessary to precisely investigate the impacts of its rapid proliferation. This study was conducted to propose the distribution and management of N. nucifera, which can cause the degradation of wildlife habitats due to the rapid spread of internal and external environmental factors that may affect the Junam wetland ecosystem. Methods: For the investigation and analysis of physical and ecological characteristics, factors of the abiotic environment such as general weather conditions, topography and water depth structure, and soil and water quality analysis, and bioenvironment characteristics such as changes in the N. nucifera community distribution were evaluated. To assess whether the differences in the soil depth and physicochemical characteristics between the N. nucifera community and the aquatic plant community are statistically significant, a One-way ANOVA was executed. Results: N. nucifera was presumably introduced in approximately 2007 and observed at a prevalence of only 0.8% in 2009, but had expanded to 11.1% in 2014. After that, the area was increased to 19.3% in 2015 and 40.0% in 2017, about twice that of the previous survey year. The rapid diffusion of an N. nucifera colony can have adverse effects on wildlife habitats and biodiversity at Junam Wetland. To solve these problems, four management methods can be proposed; water level management, mowing management, installation of posts and removal of lotus roots. Control of the N. nucifera community using these methods was judged to be suitable for cutting and water level management when considering expansion rate, water level variation, and wildlife habitat impacts. Conclusion: As the biotic and abiotic environmental factors are different for each wetland, it is necessary to determine the timing and method of management through a detailed investigation.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.86-99
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• 2010

Among Natural monument birds, a total of 11 species and 2,209 individuals were found in Nakdong river estuary from March 2007 to February 2008 including Eurasian Oystereacher (Haematopus ostralegus; No. 326), Mandarin Duck (Aix galericulata; No.327), Tundra Swan (Cygnus columbianus; No.201-1), Whooper Swan (Cygnus cygnus; No.201-2), Black-faced Spoonbilll (Platalea minor; No.205-1), Eurasian Spoonbill (Platalea leucorodia ; No.205-2), Steller's Sea Eagle (Haliaeetus pelagicus; No.243-3), White-tailed Sea Eagle (Haliaeetus albicilla ; No.243-4), Hen Harrier (Circus cyaneus; No.323-6), Common Kestrel (Falco tinnunculus; No.323-8) and Swan Goose (Anser cygnoides; No.325-1). Among the habitats for migratory birds in Korea, the Nakdong river estuary is the only place where more than 2,000 individuals of Whooper Swan(Cygnus cygnus) spend winter. Eulsukdo, Myeongji Flat and neighboring tidal flats (Myeonggeummeori, Baikhapdeung, Doyodeung, Jangjado, etc.) are major habitats for natural monument birds such as Eurasian Spoonbill(Platalea leucorodia ), Whooper Swan(Cygnus cygnus) and Swan Goose(Anser cygnoides). A colony of aquatic plants such as Common Bulrush(Scirpus triqueter) and Common Reed(Phragmites communis) serves as a feeding and resting place for birds in the Anatidae family including ducks, swans and geese. Plans for management and conservation of the habitats and the natural monument birds in Nakdong river estuary are as follows: minimization of water contamination, construction and management of aquatic plants habitats, protection of sandbanks, security of stable habitats, and consistent monitoring.

• Korean Journal of Environment and Ecology
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• v.37 no.2
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• pp.140-150
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• 2023

The Eurasian otter (Lutra lutra) is an apex predator of the riparian ecosystem. It is a keystone and an indicator species; consequently, its presence suggests a sustainable water environment. Otter is a keystone species as a predator at the top of the food web in the aquatic environment and an indicator species representing the health of the aquatic environment. Although Eurasian otters disappeared from the Han River urban water system because of anthropogenic activities like habitat destruction, poaching, and environmental pollution in the 1980s, the species were sighted in the Cheonggye Stream, Jungrang Stream, and Seongnae Stream, which are urban sections of the Han River, in 2016 and 2021. Therefore, it is pertinent to assess the habitat potential in the area for conservation and management measures to ensure its permanent presence. However, existing studies on otter habitats focused on natural rivers and reservoirs, and there is a limit to applying them to habitats artificially confined habitats in narrow spaces such as tributaries in urban areas of the Han River. This study selected the Cheonggye Stream, an artificially restored urban stream, to evaluate its potential as a habitat for Eurasian otters in urban water environments using the habitat suitability index (HSI). The HSI was calculated with selected environment attributes, such as the cover, food, and threat, that best describe the L. lutra habitat. According to the results, the confluence area of Seongbuk Stream and Cheonggye Stream and the confluence area of Cheonggye Stream and Jungnang Stream were suitable otter habitats, requiring appropriate conservation efforts. The HSI model suggests a valuable method to assess the habitat quality of Eurasian otters in urban water environments. The study is crucial as it can help rehabilitate the species' populations by identifying and managing potential Eurasian otter habitats in highly urbanized areas of the Han River basin and its tributaries.

• Animal Systematics, Evolution and Diversity
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• v.36 no.2
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• pp.128-138
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• 2020

A faunistic list and distribution of aquatic beetles were given with two newly records, Copelatus parallelus Zimmermann, 1920 (family Dytiscidae) and Scirtes sobrinus Lewis, 1895 (family Scirtidae) from Nohwa and Bogil islands in South Korea. As a result, a total of 30 species belonging to 24 genera and eight families were recognized: 12 Dytiscidae species, eight Hydrophilidae species, three Haliplidae species, two Scirtidae species, two Gyrinidae species, one Noteridae species, one Elmidae species, and one Psephenidae species. Composition and habitus photographs of all collected aquatic beetles, habitats, and the diagnostic characters of C. parallelus and S. sobrinus are provided.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.77-82
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• 2013

Phyllodictyon anastomosans (Harvey) Kraft et M.J. Wynne and Saccharina ochotensis (Miyabe) E.E. Lane C. Mayes, Druehl et G.W. Saunders are first recorded in Korea. A pantropical green alga, P. anastomosans was collected on a rock wall in the subtital zone of Jeju Island. This species has very tiny fan-shaped and netted thalli that are green in color. A cold temperate brown alga, P. ochotensis has very thick and leathery thalli that are deep brown in color. Morphological characteistics and habitats of these species are described with taxonomic accounts.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.1
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• pp.63-76
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• 2020

This study was conducted to quantitatively evaluate and analyze the alternative habitats using the HSI(Habitat Suitability Index) model of Lutra lutra in Banbyeoncheon Stream. Six variables were selected as habitat variables for Lutra lutra, including distance from waterfront, land cover within 1km from waterfront, presence of alluvial island, area of inland water and wetland, distance from roads and urbanized arid areas, and distance from aquaculture farm. The SI(Suitability Index) model and HSI model were developed based on the existing literature of Lutra lutra, the results of field surveys and expert opinions, and applied to the alternative habitats to examine the applicability of the HSI model. The results of this study can provide information on habitat evaluation to prevent the extinction of endangered Lutra lutra. In particular, it is highly applicable to the selection and evaluation of alternative habitats for Lutra lutra.