• Title/Summary/Keyword: Ponds

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Preliminary trials on effectiveness of MTR(Mass Transfer Reactor) system in aerating fish stocks

  • Mock Huh;Kim, Boo-Gil
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.1
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    • pp.23-31
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    • 1999
  • An advanced mobile technology is described for saturating water with oxygen. The MTR(Mass Transfer Reactor) is 2~10 times more effective in dissolving oxygen in water compared to most other systems used in aquaculture, because it can generate extremely small(0.005~0.05mm) bubbles. New fish farming facilities could make use of this technology to build deeper ponds for raising multiple species with optimized conditions for DO(dissolved oxygen), food, light, etc. The proposed technology offers higher DO levels with minimal operating costs. It is easy to use and maintain, with a high reproducibility. Accordingly, the MTR can be industrially applied in the treatment of fish waste and reduction of water consumption during fish farming.

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A Systematic Study on the Freshwater Cladocera from Korea (한국 담수산 지각류의 분류학적 연구)

  • 윤성명;김훈수
    • Animal Systematics, Evolution and Diversity
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    • v.3 no.2
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    • pp.175-207
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    • 1987
  • A taxonomic Study was carried out on the freshwater cladocerans from Korea during the period from August 1985 to May 1987. Materials consist of both the specimens deposited at Department of Zoology, College of Natural Sciences, Seoul National University and those collected at the freshwater regions such as rivers, lakes, ponds, bogs, rice fields, etc. During the period. As a result of examining the speciemens collected at the 123 locations in South Korea, 31 species of 7 families were identified and classified. In this paper, the authors submit the figures of the 31 species, of which the following 13 species were descirbed as hitherto unrecorded species in Korea : Diaphanosoma Leuchtenbergianum Fisher, 1858 : Simocephalus vetulus 9O.F.Mller, 1776) ; S. esxpinosus (koch, 1841); Ceriodaphnia reticulata (Jurine, 1820) ; Scapholeberis mucronata (O.F. Mller, 1785) ; Moina weismanni Ishikawa, 1896 : Ilyocryptus agilis Kurz, 1878 ; Biapertura affinis (Leydig, 1860) : Camptocercus rectirostris Schodler, 1862 ; alona costata Sars, 1862 ; Disparalona rostrata (Koch, 1841); Pseudochydorus globosus (Barird, 1843) ; Leptodora kindtii(Focke, 1844)

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Freshwater Tardigrades from Korea (한국 담수산 완보류)

  • Moon, Seung-Yeo;Kim, Won;Chang, Cheon-Young
    • Animal Systematics, Evolution and Diversity
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    • v.5 no.2
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    • pp.159-171
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    • 1989
  • Tardigrades were collected in freshwater habitats, such as rivers, streams , lakes , ponds and rice paddies at 19 different localities in Korea, during the period of May 1986 -January 1988, and seven species were identified. Dactylobiotus dispar, Macrobiotus hufellandi, M. richtersi, Hypsibius convergnes, H. dujardini, Isohypsibius granulifer, and Pseudobiotus megalonix, Five species of these except D. disparand H. dujardini, are new to Korea, which are fully described and illustrated.

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A Study on Measures for Water Quality Improvement in Irrigation Reservoir (농업용 저수지의 수질개선방안에 관한 연구)

  • 박병흔;장정렬;권순국
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1998.10a
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    • pp.500-507
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    • 1998
  • The measures for water quality improvement have been planned to introduce for several reservoirs which were badly polluted among the sites included in the Network of Agricultural Water Quality Survey (NAWQS). Considering conditions of circumstances around reservoirs, self-purification systems such as natural ecosystem, oxidation ponds with plants, grassed waterways, weirs, and manmade plant-islands are taking into account enhancing to trap nutrients in waters running off from agricultural lands. The Pollutant Run off Ratios were analysed to predict the effects of water quality improvement for self-purification systems. The cost of water quality improvement was evaluated. The correlation equation between cost and irrigation area showing high correlation coefficient was derived.

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A New Record of Scatella calida (Diptera: Ephydridae) to Korea, with a Key and a Checklist for the Genus

  • Kang, Sera;Suh, Sang Jae
    • Animal Systematics, Evolution and Diversity
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    • v.33 no.4
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    • pp.262-266
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    • 2017
  • Flies of the genus Scatella are small and dark-gray, and many species have distinctive whitish spots on their gray wings. Most species are found in damp environment, such as the borders of marshes, seashore areas, swamps, lakes, ponds, streams, and paddy fields. The Korean shore fly genus Scatella Robineau-Desvoidy has been taxonomically noted. A total of five species have been identified: S. calida Matsumura, 1915, S. nipponica Miyagi, 1977, S. obsoleta Loew, 1861, S. paludum (Meigen, 1830), and S. tenuicosta Collin, 1930. This is the first report of S. calida Matsumura, 1915 from Korea. A key to the Korean Scatella species and photographs of the external features have been provided.

Treatment Efficiency and Plant Growth of Early Stage of Pond-Wetland System at Estuary Lake (간척지 연못-습지 시스템의 질소.인 초기 처리수준 및 식물성장)

  • Yang, Hong-Mo;Choi, Soo-Myung;Yoon, Kwang-Sik
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2001.10a
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    • pp.426-430
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    • 2001
  • Treatment efficiency and plant growth of a combined Pond-Wetland system was investigated. The system is composed of primary and secondary ponds and six wetland cells. Reed and cattail were planted as vegetation of wetland cells. The removal rates of BOD, SS, T-N, and T-P were 40%, 41%, 30%, and 47% at the secondary pond, respectively. The system removal rates measured at the last wetland cell were 57%, 54%, 60%, and 68% for BOD, SS, T-N, and T-P, respectively.

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A Study on the Designer's Demands of Building Equipment Systems and Eco-friendly Environment (생태환경·설비시스템 요구도에 관한 연구)

  • Lee, Shi-Woong;Chin, Kyung-Il;Lee, Kye-Byoung;Choi, Seung-Hee
    • KIEAE Journal
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    • v.5 no.1
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    • pp.59-65
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    • 2005
  • Eco-friendly architecture, generally speaking, is considered as the activity of planting more and designing ponds, therefore many clients and constructors prefer to avoid building so due to initial construction costs. This paper aims to examine the cognition of environmental equipment systems and the applicability of echo-friendly building constructions. We examined the designer's demands of building equipment systems and eco-friendly environment and tried to deduce desirable suggestions for the system. We should solve the fundamentals of economical problems in the construction of eco-friendly buildings and we better think that government should make it a policy to advertise it and to reform the taxation system regarding environment friendly buildings.

A Study on Application of Bottom Ash with Grouting Improvement and Waterproof Grouting (지반보강 및 차수 그라우팅재로서의 Bottom Ash 활용에 관한 연구)

  • Kwon, Hyuk-Doo;Lee, Bum-Jun;Doh, Young-Gon;Lee, Song
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.1075-1082
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    • 2008
  • Recently, coal ashes which are increasing annually are buried in ash ponds as industrial wastes. However, buried coal ashes can pollute ground water and ground due to leachate from coal ashes, which are serious environmental problem. Even though a lot of researches on recycling of coal ashes have been conducted, only 15% of coal ashes are recycled up to now. And those recycled coal ashes are not bottom ashes but fly ashes. So in this study, it was proved that Bottom Ash can be used as an alternative material to O.P.C(Ordinary Portland Cement) according to laboratory test results and test field construction. Also bottom ash is more economical and environmentally friendly than O.P.C.

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The life history of lymnaea viridis, the intermediate host of fasciola hepatica, in the field (간질(肝蛭)의 중간숙주(中間宿主)인 애기물달팽이의 생태(生態))

  • Wee, Sung-ha;Park, Seung-joo;Lee, Chung-gil
    • Korean Journal of Veterinary Research
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    • v.31 no.4
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    • pp.515-518
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    • 1991
  • A field study of Lymnaea viridis, the intermediate host of Fasciola hepatica, was carried out in the eastern Chonnam area. The snail was distributed all over the place. Their major habitats were rice paddies (60.8%), followed by brooks (23.2%), irrigation canals (8.6%), and drains (5.6%). Other minor habitats included natural ponds (1.5%), lakes (0.4%), and rivers (0.1%). L. viridis was living in wet clay soil, occasionally entering water. The snails discharged egg masses when the temperature was $15{\sim}20^{\circ}C$, and the number of the snails was the highest late in October. At $9^{\circ}C$ the snails were not found on the mud: they were present deep in water or at the base of rice stubbles. These hibernation sites were discussed with the epidemiology of fascioliasis.

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Temperature Structure in Regulating Ponds (조정지에서의 수온구조)

  • 윤태훈;전시영
    • Water for future
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    • v.20 no.3
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    • pp.247-252
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    • 1987
  • The negative buoyant flow into and through a regulating pond is analysed by numerical scheme. The controlling parameter of density current in the pond is found to be the inflow densimetric Froude number, $Fr_e$. Two vortices are formed and notable at the right corner and above the sunken flow in th pond. For given inflow characteristics, the required outflow temperature, the combination of dimensions of the pond and the residence time of the inflow in the pond are determined.

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