• Journal of Bio-Environment Control
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• v.8 no.3
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• pp.209-215
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• 1999

In order to develop facility for complex farming with aquaculture and vegetable nutrient culture and to investigate growth of tilapia and water quality in the channel type aquaculture system, these experiments were carried out. When tilapia(Tilapia nilotica) was reared in the channel type aquaculture system, Quality of culture water and growth of tilapia were normal. And the growth of tilapia in the channel type and round type aquaculture system was much the same. Channel type aquaculture facilities was applicable to the dual culture system for aquaculture and vegetable culture. Channel type integrated system was composed of aquaculture and sandculture bed, and it was thought that suitable size of the system was about 1.4m(width) $\times$ 1m(height) $\times$ 20m(length).

• Journal of fish pathology
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• v.20 no.1
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• pp.41-47
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• 2007

To investigate the cause of the mass mortality during rockbream, Oplegnathus fasciatus seed production, the water quality and bacterial counts of sea water in breeding tanks was measured 20days post the hatch. During breeding of rockbream fry, the environmental factors of water quality were detected as pH, ammonia COD, phosphate at the supply of the food organisms and the seawater. pH was decreased from the 8.21 of the 1 day per hatch (dph) to 7.56 of the on the 7 dph. Ammonia was conversely increased 0.49 ppm of the 1 dph to 0.85 ppm of 10 dph. As the adding of the chlorella and the rotifer tanks, COD was increased the 3.3 times and 1.2 times than those of pre-adding respectively. The phosphate and the ammonia were also increased 1.7 and 2.3 times, with adding the chlorella respectively, which exceeded the second grade for sea water evaluation level, 0.015 ppm and 0.1 ppm respectively. Water quality was not improved by PSB (Photosynthetic Bacteria) treatment, which increased the value of COD in 1.7 times, phosphate in 2.7 times and ammonia in 1.4 times. The number of the bacteria was also increased along the dph. According to the treatment of chlorella, the number of total bacteria increased in 1.4 times and those of Vibrio sp. 1.6 times. The lethal concentration of ammonia was investigated that over than 10 ppm could killed the fry of rockbream within 28 hrs, but 40% in 2 ppm.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.296-297
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• 2000

순환여과 시스템에서 사육어가 먹이를 섭취한 후 사육수 중에 배설하는 암모니아는 생물 여과조에서 질산화과정에 의해 독성이 적은 질산염으로 축적되는데, 이러한 질산염도 고농도로 축적되면 어류의 성장에 영향을 미치게 된다. 이 실험에서는 생물여과조에 탈질 시스템을 장치하여 효과적인 질산염 제거(Arbia and van Rijn, 1995; Whitson et al., 1993)를 위한 탈질 조건별 사육수질변화 및 이에 따른 실험어인 조피볼락, Sebastes schlegeli 및 큰민어, Nibea japonica의 성장에 미치는 영향을 조사하였다. (중략)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.27-34
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• 2002

The performances of fish culture were evaluated in the integrated recirculating aquaculture system consisting of a double drain type rearing tank ($2.5 m^3$), a sedimentation tank, a floating bead filter, a foam separator and a rotating biological contactor. A system was stocked with nile tilapia at an initial rearing densities of $5\%$ (A), $5\%$ (B) and $7\%$ (C) oyer 30 days. Feed coefficient was 1.62, 1,79 and 1.80 and average daily growth rate was $0.452\%$, 0.u5% and $0.423\%$, respectively. The level of TAN was maintained below $1 g/m^3$ for $5\%$ of initial rearing density and $2-4 g/m^3$ for $7\%$. The dissolved oxygen level ($2-4 g/m^3$) was not optimum but should not be inhibitory to fish growth. The total suspended solid was completely removed during overall experimental period.

• Proceedings of the Malacological Society of Korea Conference
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• 2000.11a
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• pp.6-6
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• 2000

• Korean Aquaculture
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• v.12 no.2
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• pp.50-57
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• 2000

• Journal of Marine Life Science
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• v.5 no.2
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• pp.51-57
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• 2020

Disinfection and maintenance of rearing water in aquaculture is an essential element for the prevention of fish diseases. This is especially important in recirculating aquaculture systems (RAS) in which fish are reared at high density using recycled water. In this study, tilapia was reared in two different RAS (one with plasma generator - PW system, another without plasma generator - No PW system). In plasma treated group, UVT% of water was improved clearly, and the number of heterotrophic bacteria decreased significantly after 40 days. Total weight gain of tilapia in PW system was significantly higher, and other growth indicators were also relatively higher although not statistically significant. In addition, the fish in PW system had a 100% survival rate, and there were no histological differences between fish from both systems. Fish did not seem to be affected by the toxicity of ROS. In conclusion, it is expected that plasma water can effectively deactivate fish pathogens and improve the quality of rearing water.

• KOREAN POULTRY JOURNAL
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• v.37 no.10 s.432
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• pp.85-89
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• 2005

우리나라 양계산업은 그동안 외형적으로 사육규모의 확대를 통해 소규모 내적으로도 사육시설의 현대화를 통하여 생산성의 향상과 양계산물의 고급화를 추구해왔다. 그러나 한편으로는 국민의 환경의식의 향상과 함께 환경문제가 크게 대두되면서 환경오염방지에 대한 요구도 더욱 커지고 있으며 가축사육의 규모화 및 단지화는 지역집중화를 초래하고 계분 이용의 불균형을 심화시키는 한 원인이 되고 있다. 또한 닭 사육밀도가 지역에 따라 이미 적정선을 웃돌아 계분의 관리 잘못으로 토양오염, 대기오염, 수질오염 등의 역기능을 유발하고 있다. 생계분 조차도 돈을 받고 판매하던 시절은 이제 옛이야이가 되었고 공을 들여 잘 제조한 양질의 퇴비 조차도 판매처가 없어서 창고에 쌓아놓고 판매처를 찾아야 하는 어려움을 겪고 있는 실정이다. 그러나 1962년부터 시작된 화학비료에 대한 보조금을 2005.7.1부터 폐지되었으며 동시에 화학비료의 보조금을 유기질비료에 확대지원하고 있어서 앞으로 유기질비료의 이용은 더욱 증가할 것으로 예상된다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.274-275
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• 2000

집약적인 양식에서는 부적절한 수질과 영양, 고밀도 사육으로 인해 최적 환경하에서 사육되어지지 않는 문제점을 안고 있다. 또한 핸들링, 가두기, 수송 및 질병처리 등은 어류에게 여러가지 스트레스의 원인이 된다. 이러한 외부 스트레스 요인들은 양식장의 어류생산에 큰 영향을 미칠 수 있다. (중략)

• Journal of Aquaculture
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• v.6 no.3
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• pp.187-197
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• 1993

Studies related to water quality in catfish ponds were conducted on commercial catfish production ponds and compared with its receiving streams' water quality in central and west-central Alabama. The ponds were stocked with 10,000 fish/ha. The ponds were aerated nightly (0000-0600 hrs). Fish were fed to satiation at about the same time, six-days a week. In order to assess the pollutional strength of effluents from commercial channel catfish ponds, water samples were collected during each calender season from fall 1990 through summer 1991, and selected water quality variables were monitored. Mean values for water temperature, dissolved oxygen concentration, pH, settleable solids, total suspended soilds, volatile solids, total phosphorus, soluble reactive phosphate, biochemical oxygen demand, total ammonia nitrogen, nitrite, nitrate, and total Kjeldahl nitrogen were basically the same (P> 0.05) between samples taken from the surface and near the bottom. Concentrations of most water quality variables of catfish ponds were higher than those of receiving streams, and especially it had much higher average concentrations of nitrogen and phosphorus than streams.