• Journal of fish pathology
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• v.18 no.2
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• pp.187-195
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• 2005

Effluent of aquaculture industry has caused a growing concern regarding its environmental impact. We assessed the use of flounder farming sewage as supplement of diet, to minimize the impact of aquaculture on the environment or also establish the technique for the recycling of effluent sediment derived from land-based seawater fish farm. In order to investigate the effects of a fermented aquaculture waste on biochemical responses of olive flounder (Paralichthys olivaceus), fermented products of aquaculture wastes were used as test compounds that cause hepatic and renal stress through the induction of oxidative stress in liver and kidney. Hepatosomatic index (HSI), glutathione content and glutathione dependent enzyme were not significantly different and no correlation was found within the different types of fermentation condition or supplement concentration, except for significant increases in 50% fermentation group and 50% concentration group in case of glutathione peroxidase activity and HSI value, respectively. These results showed addition of fermented aquaculture sewage may be an economic artificial sources of diet for fish aquaculture practices without affecting the function and safety in view of biochemical examination.

• Journal of Life Science
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• v.9 no.6
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• pp.698-703
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• 1999

For the nitrate removal in recirculating aquaculture system, a denitrifying bacterium, Pseudomonas fluorescens, was isolated from municipal sewage and the cells were immobilized in modified-polyvinly alchol (PVA) gel beads. The immobilized cells in both the fixed-and fluidized-bed reactors showed 98% of denitrification efficiency with 6hr HRT, and the removal efficiency of total organic carbon (TOC) was above 90%. Form scanning electron microscopy (SEM) observation, it was known that biofilm formed in fixed-bed reactor was thicker than that formed in fluidized-bed reactor as operation time passed.

• Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.111-117
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• 2009

To develop sustainable management strategies for oyster farms in Pukman Bay, Korea, we estimated primary production using a numerical model. Because oysters are filter feeders, estimations of primary production (PP) are essential in developing management strategies. The daily PP ranged from 0.07 to 1.5 gC/$m^2$/d and showed significant spatial variations. The spatial distribution of PP was strongly associated with hydrodynamic features, and distinct patterns were observed in three different regions. In the inner bay, high PP was directly influenced by urban and agricultural sewage. The middle part of the bay had low PP, whereas PP in the outer area was high. PP was relatively low during the main oyster growth season, from late autumn to early winter. These findings represent important information for developing a management model for oyster farms in Pukman Bay.

• Journal of fish pathology
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• v.17 no.1
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• pp.57-66
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• 2004

Effects of oral administration with fermented product from sewage in land-based seawater fish farm on haematological disturbance in the olive flounder, Paralichthys olivaceus was investigated. After 4 weeks of conditioning with a basal diet, fish were divided into 4 groups and provided experimental diet (0.1, 0.5, 1.0 and 2.0%) supplement of fermented sewage for 80 days. Proximal analysis was performed for the product of sewage which was fermented by lactic acid and yeast. RBC count, hemoglobin concentration and hematocrit value were increased according to the treated periods, however, no statistical difference was observed between control and treatment groups. There were no significant difference in serum organic, inorganic compounds and enzyme activities between control and treatment groups. This study hypothesized that the supplement of fermented product from sewage in land-based seawater fish farm might be an additive supplement for source of fish diet in view of haematological examination. Recycling of the sewage may be an economic artificial sources of diet for fish aquaculture practices.

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.756-762
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• 2001

As a component for a recirculating aquaculture system, a new strain of denitrifying bacterium was isolated from municipal sewage. The isolate was motile by means of one polar flagellum, catalase-positive, and a Gram-negative rod-shaped cell measuring $0.5-0.6{\mu}m$ in width and $1.3-1.9{\mu}m$ in length. The isolate was identified as Pseudomonas fluorescens and produced dinitrogen gas via the reduction of nitrate. The optimal growth conditions (pH, temperature, carbon source, and C/N ratio) of the isolate were found to be 6.8, $30^{\circ}C$, malate, and 3, respectively. Under optimal growth conditions of P. fluorescens, dinitrogen gas was first detected in the exponential growth phase, then a small amount of nitrite was developed and converted to dinitrogen gas in the stationary phase. Pseudomonas fluorescens cells were immobilized in modified polyvinyl alcohol (PVA) gel beads, and the maximum denitrification rate was measured as $36.6 {\mu}lN_2h^-1$ per bead with an optimum cell loading of $20mg {\mu}l^-1$ and $2\%$ sodium alginate added to the PVA gel. The operating stability of the modified PVA gel beads remained unchanged for up to 43 repeated batches.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.285-290
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• 2005

Until now, korean aquaculture industry has been grown largely from a quantitative viewpoint. However, an increase of quantity has caused lots of problems producing a derived effect recently. Nearly 82% of korean aquaculture farms had been installed mainly at inshore of the southern sea and also sewage, factory wastes, high density of fishcage at the limited area and autoinfection have deteriorated inshore fisheries. The offshore have been on the rise for the solution to these problems since it has clear seawater reduces the environmental pollution with much current. As a matter of fact, the existing inshore fishcage facilities have trouble advancing to the offshore due to the rough environmental conditons such as a high sea, strong currents etc.; therefore, it is necessary to develop a new cultivating equipment fit the open sea conditons. In this research, the theoretical study and experimental analysis have been carried out for the fishcage design of the structure which is able to use at the open sea.

• Journal of Life Science
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• v.13 no.1
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• pp.47-53
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• 2003

The purpose of this study is to improve the system for biological nitrogen oxidizing process in sewage and wastewater. A bacterium having high abilities to oxidize of nitrogen was one of the possessed on Lab. The strain was identified to Bacillus sp. A8-8, based on the physiological and biochemical properties. And the strain has ability degradation crude oil. In comparison with oxidizing rates with changing initial pH and temperature, the strain Bacillus sp. A8-8 was nitrogen oxidizing ability and growth rate on the various of pH, temperature. oxidizing rates of the strain in sewage and wastewater were about 48% and 62%, respectively. The nitrogen oxidizing rate was increased in proportion to the initial concentration of glucose. The microorganism, Bacillus sp. A8-8, immobilized in ceramic carrier were evaluated for the oxidation of ammonia in culture media.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.1-6
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• 2003

Abstract: In order to improve the system for biological nitrogen oxidizing process in sewage and wastewater, a bacterium having high abilities to oxidize of nitrogen was isolated from wastewater and polluted soils. The strain was identified to Bacillus sp. CH-N, based on the physiological and biochemical properties. Characteristics and oxidizing ability of both ammonia and nitrite were examined for the strain, Bacillus sp. CH-N. The strain showed the oxidizing rate about 80% to 90% on the sewage and wastewater after 48 h culture. The nitrogen oxidizing rate was increased in proportion to the initial concentration of glucose. The microorganism, Bacillus sp. CH-N cell immobilized on ceramic carrier were evaluated for the oxidation of ammonia in culture media.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.339-344
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• 2000

Utilization of animal excreta in aquaculture can have potentials of high fish production and low maintenance costs for fish farming and it can reduce water pollution caused by animal waste disposal. Integration of wastewater treatment pond system with aquaculture has been utilized in many countries. Ecologically balanced pond ecosystem is formed through the stabilization of wastes, the growth of aquatic plants, and the cultivation of fish. The most appropriate fish for rearing in these ponds are those which can feed directly on phytoplankton, especially algae. Carp were introduced into a tertiary pond - water depth of 2.2 m, water surface area of $130\;m^2$, volume of $148\;m^3$ - of a pond system treating milk cow excreta. The carp production was $125g{\cdot}m^{-2}year^{-1}$ which falls into upper range of $18\;-\;137g{\cdot}m^{-2}year^{-1}$ of treated sewage-fed carp farming of other countries. Average $BOD_5$ and T-N of the pond was 19.8 and $21.0\;mg{\cdot}L^{-1}$ respectively, and the ecological environment of it was suitable for growth of carp. Several carp of 100g were introduced in August into a secondary pond of the treatment system, whose average $BOD_5$ and T-N was 27.9 and $30.8\;mg{\cdot}L^{-1}$ respectively. They were died within one week, which may be attributed to the depletion of dissolved oxygen at dawn. Effluents from primary treatment can be used in fish pond with dilution and those from secondary treatment can be directly funnelled into it. Waste stabilization pond treating animal excreta can be utilized for fish rearing when its water quality maintains secondary treatment level.

• Journal of Fisheries and Marine Sciences Education
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• v.12 no.1
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• pp.98-121
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• 2000

The Korean fishery encountered a difficulty situation, due to the new regime of the Exclusive Economic Zone (EEZ) and the decreasing fisheries resources in Korean waters. In addition, the coastal areas are deteriorated by industrial wastes, sewage, farming wastes and pollution from aquaculture. In this situation, it is necessary to study the TAC (total allowable catch) - based management system, the development of fishing gears and appropriate fishing methods for stock conservation, and the automation system of fishing gears for improving the efficiency of fisheries. The objective of this study is to look for an appropriate system in marine production and resource management under the new UNCLOS (United National Convention for the Law of the Sea) regime for subjects in fishing gears and methods, production system, and information, and fisheries resources management. The results of this study could be used as scientific information to maintain and develop the Korean fisheries and to establish fisheries policy for the management of fisheries resources in Korean waters.