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Sample records for aquaculture system electronic

  1. Compartmentalisation in aquaculture production systems.

    Science.gov (United States)

    Zepeda, C; Jones, J B; Zagmutt, F J

    2008-04-01

    Compartmentalisation is a new tool for disease management within a country. In aquaculture, the successful application of compartmentalisation is largely dependent on the system of production and the epidemiology of the disease(s) for which the compartment is being defined. Therefore, compartmentalisation may not be universally applicable across all systems and diseases. The paper examines the implementation of the concept, providing examples of specific industries, and discusses the application of hazard analysis and critical control points (HACCP) to the biosecurity of the system. The role of compartmentalisation in the management of aquaculture disease emergencies is also discussed.

  2. THE BIOECONOMICS OF RECIRCULATING AQUACULTURE SYSTEMS

    OpenAIRE

    Richard F. KAZMIERCZAK, Jr.; Caffey, Rex H.

    1996-01-01

    The goal of this study was to produce a detailed aquaculture production model incorporating constraints unique to closed system culture and to conduct a formal economic analysis of closed system operation. Results generated by this model indicate that less than perfect management ability can eliminate the normal advantages associated with using high protein feed. While higher protein levels produce faster growth, and for this reason are often used in the industry, the increased direct feed co...

  3. Modeling of TAN in recirculating aquaculture systems by AQUASIM

    DEFF Research Database (Denmark)

    Arvin, Erik; Pedersen, Lars-Flemming

    2011-01-01

    Modeling of total ammonium nitrogen (TAN) in recirculating aquaculture systems (RAS) contribute to identifying and quantifying the most important processes and their relative contribution to removal of TAN. AQUASIM is a flexible modular simulation system for water quality in natural and technical...... systems developed by EAWAG (Reichert, 1994). AQUASIM allows simulating complex biological, chemical and physical processes in standardized hydraulic systems. We used AQUASIM to model the steady state TAN concentrations in 12 experimental recirculating aquaculture systems (RAS) operated by DTU AQUA...

  4. Does aquaculture add resilience to the global food system?

    Science.gov (United States)

    Troell, Max; Naylor, Rosamond L; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H; Folke, Carl; Arrow, Kenneth J; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R; Gren, Asa; Kautsky, Nils; Levin, Simon A; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H; Xepapadeas, Tasos; de Zeeuw, Aart

    2014-09-16

    Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture's reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (∼4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection. PMID:25136111

  5. Does aquaculture add resilience to the global food system?

    Science.gov (United States)

    Troell, Max; Naylor, Rosamond L; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H; Folke, Carl; Arrow, Kenneth J; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R; Gren, Asa; Kautsky, Nils; Levin, Simon A; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H; Xepapadeas, Tasos; de Zeeuw, Aart

    2014-09-16

    Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture's reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (∼4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection.

  6. In-tank aeration, a necessary compliment of loaded systems in an airlift recirculating aquaculture system

    Science.gov (United States)

    Water treatment components in recirculating aquaculture systems in generally address solids removal, nitrification, circulation, aeration, and degasification. Airlift pumps in a recirculating aquaculture system can address water circulation, aeration, and degasification. Recent data indicates oxygen...

  7. Microorganisms in recirculating aquaculture systems and their management

    NARCIS (Netherlands)

    Rurangwa, E.; Verdegem, M.C.J.

    2015-01-01

    Recirculation aquaculture systems (RASs) are increasingly considered as production systems of the future with a minimum ecological impact for the production of aquatic food. To maintain a good water quality and to produce quality and healthy fishery products, the systems depend on a diverse microbia

  8. Assessment of a closed greenhouse aquaculture and hydroponic system

    Energy Technology Data Exchange (ETDEWEB)

    Head, W.D.

    1984-01-01

    Research was conducted to address three objectives: 1) to determine the nitrogen cycling of a closed greenhouse aquaculture and hydroponic system; 2) to determine the energy budget of a closed greenhouse aquaculture and hydroponic system; and 3) to determine which low cost fish diets could be used as a replacement or supplement to commercial diets for Tilapia mossambica. A 6435 liter recirculating aquaculture system was enclosed in a 32.6 m/sup 2/ greenhouse. Water was recirculated through two 416 liter trickling filter towers and three 5.5 m long hydroponic troughs. The aquaculture tank was stocked with a polyculture of channel catfish (Ictalurus punctatus) and tilapia (Tilapia mossambica) and the hydroponic troughs were planted with tomatoes (Lycopersicon esculentum). The fishes were fed a commercial fish diet and the tomatoes were irrigated with the aquaculture water using a modified Nutrient Film Technique. The fish yield was 42.2 kg and the average tomato yield from 24 plants was 4.1 kg/plant. The combined fish and tomato production accounted for 65% of the total nitrogen input. Leaf analyses and visual inspection showed that the tomato plants from the hydroponic troughs were deficient in potassium and magnesium. An energy analysis of the greenhouse and aquaculture-hydroponic system showed that when combining the energy outputs of heat, fish, and tomatoes the energy ratio (energy output/energy input) was similar to literature values for milkfish pond culture. When only the fish production was considered the energy ratio was similar to literature values reported for intensive water recirculating systems.

  9. Low-head saltwater recirculating aquaculture systems utilized for juvenile red drum production

    Science.gov (United States)

    Recirculating aquaculture systems reuse water with mechanical and biological treatment between each use and thus require wastewater treatment techniques for continuous waste removal. However, the traditional techniques and equipment utilized in recirculating aquaculture systems are expensive. The d...

  10. An Inexpensive Recirculating Aquaculture System with Multiple Use Capabilities.

    Science.gov (United States)

    Scurlock, Gerald Don, Jr.; Cook, S. Bradford; Scurlock, Carrie Ann

    1999-01-01

    Describes the construction of an inexpensive recirculating aquaculture system that can hold up to 46 pounds of fish, invertebrates, and mussels for classroom use. The system is versatile, requires little maintenance, and can be used for both teaching and research purposes. (WRM)

  11. The Presence of Pathogenic Bacteria in Recirculating Aquaculture System Biofilms and their Response to Various Sanitizers

    OpenAIRE

    King, Robin K.

    2001-01-01

    THE PRESENCE OF BACTERIAL PATHOGENS IN BIOFILMS OF RECIRCULATING AQUACULTURE SYSTEMS AND THEIR RESPONSE TO VARIOUS SANITIZERS Robin K. King ABSTRACT Recirculating aquaculture offers a prospect for successful fish farming, but this form of aquaculture presents a great potential for pathogenic microorganisms to become established in the system through the formation of biofilms. Biofilms are capable of forming on all aquaculture system components, incorporating the various microflor...

  12. Microscreen effects on water quality in replicated recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Fernandes, Paulo; Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg

    2015-01-01

    This study investigated the effects of three microscreen mesh sizes (100, 60 and 20 μm) on water quality and rainbow trout (Oncorhynchus mykiss) performance compared to a control group without microscreens, in triplicated recirculating aquaculture systems (RAS). Operational conditions were kept...

  13. Fuzzy Logic Controller based on geothermal recirculating aquaculture system

    OpenAIRE

    Hanaa M. Farghally; Doaa M. Atia; Hanaa T. El-madany; Faten H. Fahmy

    2014-01-01

    One of the most common uses of geothermal heat is in recirculation aquaculture systems (RAS) where the water temperature is accurately controlled for optimum growing conditions for sustainable and intensive rearing of marine and freshwater fish. This paper presents a design for RAS rearing tank and brazed heat exchanger to be used with geothermal energy as a source of heating water. The heat losses from the RAS tank are calculated using Geo Heat Center Software. Then a plate type heat exchang...

  14. Solid waste reduction of closed recirculated aquaculture systems by secondary culture of detritivorous organisms

    OpenAIRE

    Bischoff, Adrian A.

    2007-01-01

    Conventional production systems used in aquaculture such as ponds, raceways, net cages or recirculating systems have in common that they release large amounts of feed nutrients either in dissolved or particulate form. The efficient removal of suspended solids is a key factor for the successful operation of recirculating aquaculture systems (RAS). The here presented thesis utilised the solid wastes from modern aquaculture recirculating system for carnivorous fish for the secondary production o...

  15. Purification Performance and Production of a Re-circulating Pond Aquaculture System Based on Paddy Field

    OpenAIRE

    Gu Li; Shi-yang Zhang; Ling Tao; Xiao-li Li; Jing-hua Song; Chun-xue Zhang; Jian-qiang Zhu

    2012-01-01

    Developing improved aquaculture systems with a more efficient use of water and less environmental impact is becoming a crying need. A re-circulating aquaculture system consisting of paddy field and fish pond is a new culture mode due to aquaculture combing with agriculture. The present study focused on the purification capacity of the paddy field on nitrogen, phosphorus and organic matter, the fluctuation trend of water quality conditions during the whole rearing process and the culture effic...

  16. Control methodologies based on geothermal recirculating aquaculture system

    International Nuclear Information System (INIS)

    One of the most common uses of geothermal heat is in RAS (recirculation aquaculture systems) where the water temperature is accurately controlled for optimum growing conditions for sustainable and intensive rearing of marine and freshwater fish. This paper presents a design for RAS rearing tank and plate type heat exchanger to be used with geothermal energy as a source of heating water. A well at Umm Huweitat on the Red Sea is used as a source of geothermal energy. The heat losses from the RAS tank are calculated using Geo Heat Center Software. Then a plate type heat exchanger is designed using the epsilon–NTU (number of transfer units) analysis method. For optimal growth and abundance of production, a different techniques of control system are applied to control the water temperature. The total system is built in MATLAB/SIMULINK to study the overall performance of control unit. Finally, a comparison between PI, Fuzzy-PID, and Fuzzy Logic Control has been done. - Highlights: • Design recirculating aquaculture system using geothermal energy. • Design a PI controller for water temperature control. • Design a Fuzzy logic controller for water temperature control. • Design a Fuzzy-PID controller for water temperature control. • Comparison between different control systems

  17. Application of Aquaculture Monitoring System Based on CC2530

    Science.gov (United States)

    Chen, H. L.; Liu, X. Q.

    In order to improve the intelligent level of aquaculture technology, this paper puts forward a remote wireless monitoring system based on ZigBee technology, GPRS technology and Android mobile phone platform. The system is composed of wireless sensor network (WSN), GPRS module, PC server, and Android client. The WSN was set up by CC2530 chips based on ZigBee protocol, to realize the collection of water quality parameters such as the water level, temperature, PH and dissolved oxygen. The GPRS module realizes remote communication between WSN and PC server. Android client communicates with server to monitor the level of water quality. The PID (proportion, integration, differentiation) control is adopted in the control part, the control commands from the android mobile phone is sent to the server, the server again send it to the lower machine to control the water level regulating valve and increasing oxygen pump. After practical testing to the system in Liyang, Jiangsu province, China, temperature measurement accuracy reaches 0.5°C, PH measurement accuracy reaches 0.3, water level control precision can be controlled within ± 3cm, dissolved oxygen control precision can be controlled within ±0.3 mg/L, all the indexes can meet the requirements, this system is very suitable for aquaculture.

  18. Solar energy system design for a lobster aquaculture facility

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-30

    In aquaculture, as in most manufacturing processes, the operating cost is greatly dependent upon the cost of energy. The objectives were to: (a) analyze the power requirements for a lobster aquaculture plant, and (b) to evaluate the use of solar energy as a cost reduction measure in plant operation. A flat plate collector system capable of supplying heat alone was compared with a total energy system in which both electrical power and heat were supplied. The flat plate collector was not cost effective because when heat was needed in December, the least amount of heat was available from solar radiation. Therefore, the collector area and cost were prohibitive. However, the total energy system was cost effective when the capital investment was amortized over ten or more years. The optimum solar power plant was designed to provide 100% of the average yearly power demands, or 60% of the December power requirement. This plant would consist of 60,000 square feet of mirror surface (3.5 acres of land for 40% packing density) which would concentrate 1500 to 2000 suns on a receiver mounted on an 85 foot tower. In the tower would be the three storage stoves which would contain the heat required to operate a 343 KWe Brayton gas turbine engine and alternator for 27 hours. Equipment to generate 3 million kw-hr annually will cost an estimated $1.3 million.

  19. Exergetic performance analysis of a recirculating aquaculture system

    Energy Technology Data Exchange (ETDEWEB)

    Kucuk, Haydar [Mechanical Engineering Department, Guemueshane University, 29000 Guemueshane (Turkey); Midilli, Adnan [Energy Division, Mechanical Engineering Department. Nigde University, 51000 Nigde (Turkey); Oezdemir, Atilla; Cakmak, Eyuep [Central Fisheries Research Institute, Ministry of Agricultural and Rural Affairs, Trabzon (Turkey); Dincer, Ibrahim [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ont. (Canada)

    2010-05-15

    This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period. (author)

  20. Microbial diversity of biological filters in recirculating aquaculture systems.

    Science.gov (United States)

    Schreier, Harold J; Mirzoyan, Natella; Saito, Keiko

    2010-06-01

    Development of environmentally sustainable farming of marine and freshwater species using recirculating aquaculture systems (RASs) requires a complete understanding of the biological component involved in wastewater treatment. This component integrates biofilters composed of microbial communities whose structure, dynamics, and activities are responsible for system success. Engineering highly efficient, environmentally sound, disease-free, and economically viable systems necessitates a thorough knowledge of microbial processes involved in all facets of RAS biofilters and has only recently been the focus of comprehensive studies. These studies have included the application of molecular tools to characterize community diversity and have identified key processes useful for improving system performance. In this paper we summarize the current understanding of the microbial diversity and physiology of RAS biofilters and discuss directions for future studies. PMID:20371171

  1. Fuzzy Logic Controller based on geothermal recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Hanaa M. Farghally

    2014-01-01

    Full Text Available One of the most common uses of geothermal heat is in recirculation aquaculture systems (RAS where the water temperature is accurately controlled for optimum growing conditions for sustainable and intensive rearing of marine and freshwater fish. This paper presents a design for RAS rearing tank and brazed heat exchanger to be used with geothermal energy as a source of heating water. The heat losses from the RAS tank are calculated using Geo Heat Center Software. Then a plate type heat exchanger is designed using the epsilon – NTU analysis method. For optimal growth and abundance of production, a Fuzzy Logic control (FLC system is applied to control the water temperature (29 °C. A FLC system has several advantages over conventional techniques; relatively simple, fast, adaptive, and its response is better and faster at all atmospheric conditions. Finally, the total system is built in MATLAB/SIMULINK to study the overall performance of control unit.

  2. The Use of Vision in a Sustainable Aquaculture Feeding System

    Directory of Open Access Journals (Sweden)

    Jer-Vui Lee

    2013-10-01

    Full Text Available Dairy feeding causes significant water pollution. By controlling the proper amount of feed, reducing the waste to minimum will effectively reduce the problem of water contamination. In this project, a Sustainable Aquaculture Feed System (SAFS has been designed and developed. It can automatically feed the fishes by estimating fishes’ appetite through machine vision. The discussion includes design and optimization of the vision system using Labview as well as the integration of various components in the SAFS. With the developed algorithm, the system is able to detect the presence of fishes and count the number of fishes. The outcome is able to estimate and infer the fish appetite. Therefore, the feeding time can be planned ahead. In addition, the system includes a Graphical User Interface (GUI for monitoring, display the feeding status and sensors reading such as pH, turbidity and temperature.

  3. Tracing dissolved organic matter (DOM) from land-based aquaculture systems in North Patagonian streams.

    Science.gov (United States)

    Nimptsch, Jorge; Woelfl, Stefan; Osorio, Sebastian; Valenzuela, Jose; Ebersbach, Paul; von Tuempling, Wolf; Palma, Rodrigo; Encina, Francisco; Figueroa, David; Kamjunke, Norbert; Graeber, Daniel

    2015-12-15

    Chile is the second largest producer of salmonids worldwide. The first step in the production of salmonids takes place in land-based aquacultures. However, the effects of the discharge from these aquacultures on stream dissolved organic matter (DOM) content, molecular composition and degradability are unknown. The aim of this study was thus to investigate the inputs of anthropogenic DOM from land-based aquaculture to the predominantly pristine river systems of North Patagonia. We hypothesized, that i) DOM exported from land-based aquaculture mainly consists of protein-like fluorescence (tyrosine and tryptophan) released from fish feces and food remains, and that ii) this DOM is highly degradable and therefore rapidly turned-over within the receiving streams. In the North Patagonian region we conducted a screening of ten land-based aquacultures and an intensive sampling campaign for one aquaculture. This was combined with longitudinal transects and a degradation experiment in order to couple the composition of DOM exported from land-based aquacultures to its degradability in streams. We measured dissolved organic carbon (DOC) concentration by high-temperature catalytic oxidation and DOM composition by fluorescence spectroscopy and parallel factor analysis. In the effluent of the ten screened aquacultures and in the repeated sampling of one aquaculture, we consistently found an increase of DOC concentrations and a dominance of protein-like fluorescence. The protein-like fluorescence rapidly disappeared downstream of the aquacultures, and in the degradation experiment. 21% of the DOC export from the repeatedly sampled aquaculture resulted from food addition and 76% from fish production. We conclude that large amounts of degradable DOM are exported from land-based aquacultures. This probably has strong effects on the ecological structure and function of North Patagonian streams, and similarly affected streams worldwide.

  4. Low-head recirculating aquaculture system for juvenile red drum production

    Science.gov (United States)

    The USDA Agricultural Research Service and the Center for Aquaculture and Stock Enhancement at Harbor Branch Oceanographic Institute-FAU (HBOI-FAU) are collaborating to evaluate low-head recirculating aquaculture system designs to intensively produce red drum juveniles as part of the Florida Fish an...

  5. Life cycle assessment of food production in integrated agriculture–aquaculture systems of the Mekong Delta

    NARCIS (Netherlands)

    Phong, L.T.; Boer, de I.J.M.; Udo, H.M.J.

    2011-01-01

    This study evaluated the environmental impact of integrated agriculture–aquaculture (IAA) farming systems in the Mekong Delta that differ in types of aquaculture intensification. Daily inputs and outputs for rice, fruits, vegetables, pigs, poultry, and fish were collected on 11 farms over a period o

  6. Does aquaculture add resilience to the global food system?

    NARCIS (Netherlands)

    Troell, M.; Naylor, R.; Metian, M.; Beveridge, M.; Tyedmers, P.H.; Folke, C.; Arrow, K.J.; Barrett, S.; Crépin, A.S.; Ehrlich, P.; Gren, A.; Kautsky, N.; Levin, S.A.; Nyborg, K.; Osterblom, H.; Polasky, S.; Scheffer, M.; Walker, B.; Xepapadeas, A.; de Zeeuw, A.J.

    2014-01-01

    Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment t

  7. Aquaculture Industry Potential and Issues: A Case from Cage Culture System Entrepreneurs: Suggestions for Intensification of Aquaculture Industry

    Directory of Open Access Journals (Sweden)

    A. N.A. Faiz

    2010-01-01

    Full Text Available Problem statement: Cage culture has become a popular aquaculture system nowadays. In the recent statistics provided by DOF, the cage culture system has generated almost USD 400 m (RM 1.39 b of income per year. In order to further intensify this economic activity the Ministry of Agriculture and Agro-based Industry (MOA through the DOF has zoned the aquaculture industry via Aquaculture Industry Zone (ZIA Programs throughout Malaysia. Cage culture system seems to have the ability to be a catalyst in enhancing the economy level of local people but it is well known that certain problems must be overcome first before the potential can be clearly seen. Thus the main focus of this study is to clarify all the potentials and problems faced by the cage culture system entrepreneurs in running their aquaculture activity. Approach: The research approach for this study was a qualitative case study that provided an in-depth description of potentials and issues in aquaculture industry in the district of Kuala Pahang, Malaysia. Data was gained using a Focus Group Discussion (FGD among the cage culture system entrepreneurs guided by an interview guide. A total of 10 cage culture entrepreneurs were selected as the FGD members. The questions served as a guide, but allowed respondents freedom and flexibility in their answers. The findings were in descriptive analysis. Results: The cage culture system was found to provide better income that lead to a higher quality of life for the entrepreneurs, positive intangible values existed among the entrepreneurs; experiences have taught them to become self independent. There were problems identified such as no independence in selecting the fingerlings, environmental problems seem to burden them, unstable pellet price, no official agreement between them and the government emphasizing the portion of the river is given to them for running their business and lot of bureaucracies that the entrepreneurs need to face. Conclusion

  8. The evaluation of oxygen and carbon dioxide transfer associated with airlifts in recirculating aquaculture systems

    Science.gov (United States)

    Airlifts in recirculating aquaculture systems (RAS) provide aeration, degasification, and water circulation. They allow the simplification of systems, and if designed properly, can reduce the capital costs and minimize operation and maintenance associated with alternative pumping systems. In order t...

  9. Long term/low dose formalin exposure to small-scale recirculation aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg; Nielsen, Jeppe L.;

    2010-01-01

    Repetitive long term formalin application at low dose was investigated to determine the effect on formaldehyde removal rate, biofilter nitrification and the microbial composition in small-scale recirculation aquaculture biofilters. Six pilot-scale recirculation aquaculture systems holding rainbow...... Nitrobacter sp. was not detected. The relative abundances of AOB and NOB in the untreated system were generally higher compared to the system exposed to formalin. Low dose formalin in recirculated aquaculture systems proved to be a possible treatment strategy, as the effect on nitrification was minimal. Since...

  10. Effect of Wind-solar Complementary Increasing Oxygen System in Aquaculture

    Directory of Open Access Journals (Sweden)

    Guodong You

    2013-12-01

    Full Text Available In order to explore a sustainable aquaculture methodology, water was increased oxygen by a wind-solar power which was tested in a production period of the Penaeus vannamei in paper. The result shows that, compareing with the conventional aerating comparison, the system could improve water environment in ponds and dissolved oxygen, temperature, pH value and the content of nitrite stably and uniformly change; make full use of wind energy and solar energy clean energy, save 100% on power consumption, 15.9% on bait, 46.0% on drug; save aquaculture costs, increase income 282%. Using "Wind-solar" complementary increasing oxygen can improve water environment, save power, reduce aquaculture costs, increase aquaculture production and income, provide a new thought and method for green and ecological aquaculture, so it has high value of practical application.

  11. Risk Analysis of Tilapia Recirculating Aquaculture Systems: A Monte Carlo Simulation Approach

    OpenAIRE

    Kodra, Bledar

    2007-01-01

    Risk Analysis of Tilapia Recirculating Aquaculture Systems: A Monte Carlo Simulation Approach Bledar Kodra (ABSTRACT) The purpose of this study is to modify an existing static analytical model developed for a Re-circulating Aquaculture Systems through incorporation of risk considerations to evaluate the economic viability of the system. In addition the objective of this analysis is to provide a well documented risk based analytical system so that individuals (investors/lenders) c...

  12. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  13. Dietary carbohydrate composition can change waste production and biofilter load in recirculating aquaculture systems

    NARCIS (Netherlands)

    Meriac, A.; Eding, E.H.; Schrama, J.W.; Kamstra, A.; Verreth, J.A.J.

    2014-01-01

    This study investigated the effect of dietary carbohydrate composition on the production, recovery and degradability of fecal waste from rainbow trout (Oncorhynchus mykiss) in recirculating aquaculture systems (RAS). Dietary carbohydrate composition was altered by substituting starch with non-starch

  14. Use of planted biofilters in integrated recirculating aquaculture-hydroponics systems in the Mekong Delta, Vietnam

    DEFF Research Database (Denmark)

    Trang, N.T.D.; Brix, Hans

    2014-01-01

    The feasibility of using planted biofilters for purification of recirculated aquaculture water in the Mekong Delta of Vietnam was assessed. The plant trenches were able to clean tilapia aquaculture water and to maintain good water quality in the fish tanks without renewal of the water. NH4-N was ...... rates of 725 kg N and 234 kg P ha-1 year-1. This research demonstrates that integrated recirculating aquaculture-hydroponics (aquaponics) systems provide significant water savings and nutrient recycling as compared with traditional fish ponds. © 2012 John Wiley & Sons Ltd....

  15. Nutrient fate in aquacultural systems for waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Dontje, J.H.; Clanton, C.J.

    1999-08-01

    Twelve small, recirculating aquacultural systems were operated for livestock waste treatment to determine nutrient fate. Each system consisted of a 730-L fish tank coupled in a recirculating loop with three sand beds (serving as biofilters) in parallel. Fish (Tilapia species) were grown in the tanks while cattails, reed canary grass, and tomatoes were grown in separate sand beds. Swine waste was added to the fish tanks every other day at average rates of 50, 72, 95, and 118 kg-COD/ha/day of fish tank surface (three replications of each loading rate). Water from the fish tanks was filtered through the sand beds three times per day with 20% of the tank volume passing through the sand each day. The systems were operated in a greenhouse for eight months (21 July to 8 March). Aboveground plant matter was harvested at eight-week intervals. The fish were removed after four months and the tanks were restocked with fingerlings. Initial and final nitrogen (N), phosphorus (P), and potassium (K) contents of the system components, as well as that of the harvested plants and fish, were determined. Nutrient balance calculations revealed that 30 to 68% of added N was lost from the systems, probably via denitrification. Nutrient removal by plants was 6 to 18% for N, 8 to 21% for P, and 25 to 71% for K, with tomatoes (foliage and fruit) accounting for the majority of the removal. Plant growth was limited by growing conditions (particularly day length), not be nutrient availability. Fish growth was limited by temperature; thus nutrient extraction by the fish was minimal. Under the conditions of this experiment, the system required supplemental aeration.

  16. Geothermal aquaculture project: Real Property Systems Inc. , Harney Basin, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    1981-08-14

    Real Property Systems Inc., (RPS) owns two parcels in the vicinity of Harney Lake, Oregon. One parcel is 120 acres in size, the other is 200 acres. A study concludes that the 200 acre parcel has the greater potential for geothermal development. RPS is interested in an aquaculture operation that produces fresh water prawns, (Macrobrachium rosenbergii) for the market. To supply the heat necessary to maintain the ideal temperature of 82/sup 0/F desired for these prawns, a geothermal resource having a 150/sup 0/F temperature or higher, is needed. The best estimate is that 150/sup 0/F water can be found from a minimum 1090 feet depth to 2625 feet, with no absolute assurances that sufficient quantities of geothermal waters exist without drilling for the same. This study undertakes the preliminary determination of project economics so that a decision can be made whether or not to proceed with exploratory drilling. The study is based on 10 acres of ponds, with a peak requirement of 2500 gpm of 150/sup 0/F geothermal water.

  17. LCA and emergy accounting of aquaculture systems: towards ecological intensification.

    Science.gov (United States)

    Wilfart, Aurélie; Prudhomme, Jehane; Blancheton, Jean-Paul; Aubin, Joël

    2013-05-30

    An integrated approach is required to optimise fish farming systems by maximising output while minimising their negative environmental impacts. We developed a holistic approach to assess the environmental performances by combining two methods based on energetic and physical flow analysis. Life Cycle Assessment (LCA) is a normalised method that estimates resource use and potential impacts throughout a product's life cycle. Emergy Accounting (EA) refers the amount of energy directly or indirectly required by a product or a service. The combination of these two methods was used to evaluate the environmental impacts of three contrasting fish-farming systems: a farm producing salmon in a recirculating system (RSF), a semi-extensive polyculture pond (PF1) and an extensive polyculture pond (PF2). The RSF system, with a low feed-conversion ratio (FCR = 0.95), had lower environmental impacts per tonne of live fish produced than did the two pond farms, when the effects on climate change, acidification, total cumulative energy demand, land competition and water dependence were considered. However, RSF was clearly disconnected from the surrounding environment and depended highly on external resources (e.g. nutrients, energy). Ponds adequately incorporated renewable natural resources but had higher environmental impacts due to incomplete use of external inputs. This study highlighted key factors necessary for the successful ecological intensification of fish farming, i.e., minimise external inputs, lower the FCR, and increase the use of renewable resources from the surrounding environment. The combination of LCA and EA seems to be a practical approach to address the complexity of optimising biophysical efficiency in aquaculture systems.

  18. LCA and emergy accounting of aquaculture systems: towards ecological intensification.

    Science.gov (United States)

    Wilfart, Aurélie; Prudhomme, Jehane; Blancheton, Jean-Paul; Aubin, Joël

    2013-05-30

    An integrated approach is required to optimise fish farming systems by maximising output while minimising their negative environmental impacts. We developed a holistic approach to assess the environmental performances by combining two methods based on energetic and physical flow analysis. Life Cycle Assessment (LCA) is a normalised method that estimates resource use and potential impacts throughout a product's life cycle. Emergy Accounting (EA) refers the amount of energy directly or indirectly required by a product or a service. The combination of these two methods was used to evaluate the environmental impacts of three contrasting fish-farming systems: a farm producing salmon in a recirculating system (RSF), a semi-extensive polyculture pond (PF1) and an extensive polyculture pond (PF2). The RSF system, with a low feed-conversion ratio (FCR = 0.95), had lower environmental impacts per tonne of live fish produced than did the two pond farms, when the effects on climate change, acidification, total cumulative energy demand, land competition and water dependence were considered. However, RSF was clearly disconnected from the surrounding environment and depended highly on external resources (e.g. nutrients, energy). Ponds adequately incorporated renewable natural resources but had higher environmental impacts due to incomplete use of external inputs. This study highlighted key factors necessary for the successful ecological intensification of fish farming, i.e., minimise external inputs, lower the FCR, and increase the use of renewable resources from the surrounding environment. The combination of LCA and EA seems to be a practical approach to address the complexity of optimising biophysical efficiency in aquaculture systems. PMID:23531606

  19. Multidrug-Resistance and Toxic Metal Tolerance of Medically Important Bacteria Isolated from an Aquaculture System

    OpenAIRE

    Resende, Juliana Alves; Silva, Vânia L.; Fontes, Cláudia Oliveira; Souza-Filho, Job Alves; de Oliveira, Tamara Lopes Rocha; Coelho, Cíntia Marques; César, Dionéia Evangelista; Diniz, Cláudio Galuppo

    2012-01-01

    The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified an...

  20. The economic sustainability of land-based aquaculture systems: An integrated analysis

    OpenAIRE

    Bennich, Therese

    2015-01-01

    The global demand for fish is rising, caused by population growth and an increasing per capita consumption of fish. At the same time, production from capture fisheries has stagnated and there are growing concerns about the environmental impact of sea-based aquaculture. Future developments in the fishing industry must meet demand, without compromising the environment. Technological advancements have introduced land-based fish farming and Recirculating Aquaculture Systems (RAS) technology as a ...

  1. Feasibility of adopting aquaculture without detriment to existing farming practices: a case of Bangladesh farming systems

    OpenAIRE

    Ahmed, M.; Rab, M.A.

    1992-01-01

    Integrating agriculture aquaculture that would draw inputs from on farm sources is viewed as a viable option to improve the productivity, income and resource use efficiency of existing farms in Bangladesh. To assess the existing resource availability, use pattern and efficiency before introducing new aquaculture technology within the existing farm systems, a survey of 330 pond operating farm households was conducted in six selected unions from two thanas (subdistricts) of Bangladesh.

  2. Influence of carbohydrate addition on nitrogen transformations and greenhouse gas emissions of intensive aquaculture system.

    Science.gov (United States)

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Sharma, Keshab; Khanal, Samir Kumar

    2014-02-01

    Aquaculture is one of the fastest-growing segments of the food economy in modern times. It is also being considered as an important source of greenhouse gas (GHG) emissions. To date, limited studies have been conducted on GHG emissions from aquaculture system. In this study, daily addition of fish feed and soluble starch at a carbon-to-nitrogen (C/N) ratio of 16:1 (w/w) was used to examine the effects of carbohydrate addition on nitrogen transformations and GHG emissions in a zero-water exchange intensive aquaculture system. The addition of soluble starch stimulated heterotrophic bacterial growth and denitrification, which led to lower total ammonia nitrogen, nitrite and nitrate concentrations in aqueous phase. About 76.2% of the nitrogen output was emitted in the form of gaseous nitrogen (i.e., N2 and N2O) in the treatment tank (i.e., aquaculture tank with soluble starch addition), while gaseous nitrogen accounted for 33.3% of the nitrogen output in the control tank (i.e., aquaculture tank without soluble starch addition). Although soluble starch addition reduced daily N2O emissions by 83.4%, it resulted in an increase of daily carbon dioxide (CO2) emissions by 91.1%. Overall, starch addition did not contribute to controlling the GHG emissions from the aquaculture system.

  3. Influence of carbohydrate addition on nitrogen transformations and greenhouse gas emissions of intensive aquaculture system.

    Science.gov (United States)

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Sharma, Keshab; Khanal, Samir Kumar

    2014-02-01

    Aquaculture is one of the fastest-growing segments of the food economy in modern times. It is also being considered as an important source of greenhouse gas (GHG) emissions. To date, limited studies have been conducted on GHG emissions from aquaculture system. In this study, daily addition of fish feed and soluble starch at a carbon-to-nitrogen (C/N) ratio of 16:1 (w/w) was used to examine the effects of carbohydrate addition on nitrogen transformations and GHG emissions in a zero-water exchange intensive aquaculture system. The addition of soluble starch stimulated heterotrophic bacterial growth and denitrification, which led to lower total ammonia nitrogen, nitrite and nitrate concentrations in aqueous phase. About 76.2% of the nitrogen output was emitted in the form of gaseous nitrogen (i.e., N2 and N2O) in the treatment tank (i.e., aquaculture tank with soluble starch addition), while gaseous nitrogen accounted for 33.3% of the nitrogen output in the control tank (i.e., aquaculture tank without soluble starch addition). Although soluble starch addition reduced daily N2O emissions by 83.4%, it resulted in an increase of daily carbon dioxide (CO2) emissions by 91.1%. Overall, starch addition did not contribute to controlling the GHG emissions from the aquaculture system. PMID:24140689

  4. Implications of Extracellular Polymeric Substance Matrices of Microbial Habitats Associated with Coastal Aquaculture Systems

    Directory of Open Access Journals (Sweden)

    Juan Carlos Camacho-Chab

    2016-08-01

    Full Text Available Coastal zones support fisheries that provide food for humans and feed for animals. The decline of fisheries worldwide has fostered the development of aquaculture. Recent research has shown that extracellular polymeric substances (EPS synthesized by microorganisms contribute to sustainable aquaculture production, providing feed to the cultured species, removing waste and contributing to the hygiene of closed systems. As ubiquitous components of coastal microbial habitats at the air–seawater and seawater–sediment interfaces as well as of biofilms and microbial aggregates, EPS mediate deleterious processes that affect the performance and productivity of aquaculture facilities, including biofouling of marine cages, bioaccumulation and transport of pollutants. These biomolecules may also contribute to the persistence of harmful algal blooms (HABs and their impact on cultured species. EPS may also exert a positive influence on aquaculture activity by enhancing the settling of aquaculturally valuable larvae and treating wastes in bioflocculation processes. EPS display properties that may have biotechnological applications in the aquaculture industry as antiviral agents and immunostimulants and as a novel source of antifouling bioproducts.

  5. Aquaculture; Acquacoltura

    Energy Technology Data Exchange (ETDEWEB)

    De Murtas, I.D. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1998-12-01

    This paper attempts an overview of the progress made in the field of aquaculture. Aquaculture is a system of techniques strongly influenced by natural environmental conditions. Aquaculture as a biological technique oriented towards the production of useful aquatic organisms, is reaching a stage of consolidation which will place it on an equal footing which agriculture and animal husbandry. Aquaculture provides important economic and nutritional benefits to many regions of developing world. In 1994, over 90 percent of total aquaculture production was in Asia, with China, India, Japan, Indonesia, Thailand, Philippines and Republic of Korea as the seven leader producers. [Italiano] L`acquacoltura, vale a dire l`arte di riprodurre artificialmente pesci, alghe, molluschi e crostacei ed altri organismi acquatici utili all`uomo, si presenta oggi come un`attivita` di assoluto rilievo nell`insieme dei vari comparti di produzione alimentare. L`aumento della produzione e` costante anche se cinque paesi asiatici (Cina, India, Giappone, Filippine e Corea del Sud) contribuiscono per l`80% al volume della produzione mondiale. Nel presente lavoro vengono descritti lo stato dell`acquacoltura e della maricoltura nel mondo e le filiere di allevamento delle principali specie.

  6. Dietary carbohydrates and denitrification in recirculating aquaculture systems

    OpenAIRE

    Meriac, A.

    2014-01-01

    Due to overfishing of global fish stocks and increasing fish meal prices, plant ingredients are being increasingly used as an alternative source of protein in fish feeds. However, the inclusion of unpurified plant ingredients will also increase the content of fibers in feeds. Fibers are nearly indigestible and will therefore increase solid waste production in aquaculture. This solid waste can be used to as a carbon source for denitrification to control nitrate levels in recirculating aquacult...

  7. Nitrogen transformations in intensive aquaculture system and its implication to climate change through nitrous oxide emission.

    Science.gov (United States)

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Sharma, Keshab; Brotto, Ariane Coelho; Khanal, Samir Kumar

    2013-02-01

    The rapid development of aquaculture could result in significant environmental concerns such as eutrophication and climate change. However, to date, very few studies have been conducted to investigate nitrogen transformations in aquaculture systems; and specifically the emission of nitrous oxide (N(2)O), which is an important greenhouse gas and ozone-depleting substance. In this study, nitrogen transformations in intensive laboratory-scale Chinese catfish (Clarias fuscus) aquaculture systems were investigated by identifying and quantifying N(2)O emissions. Results indicated that about 1.3% of the nitrogen input was emitted as N(2)O gas. Dissolved oxygen (DO) concentrations and feeding rates had significant effects on N(2)O emissions. Higher N(2)O emissions were obtained in aquaculture systems with lower DO concentrations and higher feeding rates. Both nitrification and denitrification appeared to be responsible for the emissions of N(2)O. Key factors which correlated with the N(2)O emission rate in aquaculture systems were NO(2)(-), DO and total ammonia nitrogen concentrations.

  8. Ornithinimicrobium tianjinense sp. nov., isolated from a recirculating aquaculture system.

    Science.gov (United States)

    Liu, Liang-Zi; Liu, Ying; Chen, Zhu; Liu, Hong-Can; Zhou, Yu-Guang; Liu, Zhi-Pei

    2013-12-01

    A Gram-positive, strictly aerobic and heterotrophic, non-spore-forming actinobacterium (strain B2(T)) isolated from a recirculating aquaculture system was studied for its taxonomic position. Strain B2(T) formed a rudimentary substrate-mycelium that fragmented into short rod-shaped to coccoid cells (0.5 µm×0.5-2.2 µm or 0.5-1.0 µm in diameter). Colonies were yellow, smooth, circular and 1.5-2.0 mm in diameter after incubation on TSA for 3 days at 30 °C. Strain B2(T) grew at 20-40 °C (optimal, 30 °C) and pH 5.5-9.5 (optimal, 6.5-7.0) and in the presence of 0-9% (w/v) NaCl (optimal, 1%). The predominant menaquinone of strain B2(T) was MK-8(H4). The cell-wall peptidoglycan of strain B2(T) contained the amino acids ornithine, glutamic acid, alanine, glycine and aspartic acid. The major polar lipids were phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were iso-C15 : 0, iso-C16 : 0 and summed feature 9. Its DNA G+C content was 68.3 mol% (Tm). Analysis of 16S rRNA gene sequences indicated that strain B2(T) was related phylogenetically to members of the genus Ornithinimicrobium with highest similarity (96.6 %) to Ornithinimicrobium kibberense DSM 17687(T), followed by Ornithinimicrobium humiphilum DSM 12362(T) (96.3 %), Ornithinimicrobium pekingense LW6(T) (96.2%) and Ornithinimicrobium murale 01-Gi-040(T) (94.8%). On basis of phenotypic, chemotaxonomic and phylogenetic data, it was concluded that strain B2(T) represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium tianjinense sp. nov. is proposed. The type strain is B2(T) ( =CGMCC 1.12160(T) =JCM 18464(T)). PMID:23907216

  9. Applicability of photodynamic antimicrobial chemotherapy as an alternative to inactivate fish pathogenic bacteria in aquaculture systems.

    Science.gov (United States)

    Arrojado, Cátia; Pereira, Carla; Tomé, João P C; Faustino, Maria A F; Neves, Maria G P M S; Tomé, Augusto C; Cavaleiro, José A S; Cunha, Angela; Calado, Ricardo; Gomes, Newton C M; Almeida, Adelaide

    2011-10-01

    Aquaculture activities are increasing worldwide, stimulated by the progressive reduction of natural fish stocks in the oceans. However, these activities also suffer heavy production and financial losses resulting from fish infections caused by microbial pathogens, including multidrug resistant bacteria. Therefore, strategies to control fish infections are urgently needed, in order to make aquaculture industry more sustainable. Antimicrobial photodynamic therapy (aPDT) has emerged as an alternative to treat diseases and prevent the development of antibiotic resistance by pathogenic bacteria. The aim of this work was to evaluate the applicability of aPDT to inactivate pathogenic fish bacteria. To reach this objective a cationic porphyrin Tri-Py(+)-Me-PF was tested against nine pathogenic bacteria isolated from a semi-intensive aquaculture system and against the cultivable bacteria of the aquaculture system. The ecological impact of aPDT in the aquatic environment was also tested on the natural bacterial community, using the overall bacterial community structure and the cultivable bacteria as indicators. Photodynamic inactivation of bacterial isolates and of cultivable bacteria was assessed counting the number of colonies. The impact of aPDT in the overall bacterial community structure of the aquaculture water was evaluated by denaturing gel gradient electrophoresis (DGGE). The results showed that, in the presence of Tri-Py(+)-Me-PF, the growth of bacterial isolates was inhibited, resulting in a decrease of ≈7-8 log after 60-270 min of irradiation. Cultivable bacteria were also considerably affected, showing decreases up to the detection limit (≈2 log decrease on cell survival), but the inactivation rate varied significantly with the sampling period. The DGGE fingerprint analyses revealed changes in the bacterial community structure caused by the combination of aPDT and light. The results indicate that aPDT can be regarded as a new approach to control fish

  10. Peracetic acid is a suitable disinfectant for recirculating fish-microalgae integrated multi-trophic aquaculture systems

    DEFF Research Database (Denmark)

    Liu, Dibo; Behrens, Sascha; Pedersen, Lars-Flemming;

    2016-01-01

    tIntegrated multi-trophic aquaculture (IMTA) is a promising direction for the sustainable developmentof aquaculture. Microalgae have good potential to be integrated with recirculating aquaculture sys-tems because they can use the nitrogen excreted from fish and share the same optimal pH value asin...... aquaculture. As a byproduct, the microalgae biomass can be used for fish feed or biofuel. How-ever, the recirculating fish-microalgae IMTA system is under constant threat from fish pathogens andphytoplankton-lytic bacteria. Therefore, it is necessary to apply proper disinfectants as prophylaxis ortreatment...

  11. Characterising organic matter in recirculating aquaculture systems with fluorescence EEM spectroscopy

    DEFF Research Database (Denmark)

    Hambly, Adam; Arvin, Erik; Pedersen, Lars-Flemming;

    2015-01-01

    The potential of recirculating aquaculture systems (RAS) in the aquaculture industry is increasingly being acknowledged. Along with intensified application, the need to better characterise and understand the accumulated dissolved organic matter (DOM) within these systems increases. Mature RASs...... there was considerable variation between the five fluorescence components with respect to the degree of accumulation with feed loading. The five components were found to originate from three sources: the feed; the influent tap water (groundwater); and processes related to the fish and the water treatment system...

  12. The accumulation of substances in Recirculating Aquaculture Systems (RAS) affects embryonic and larval development in common carp Cyprinus carpio

    NARCIS (Netherlands)

    Martins, C.I.; Pristin, M.G.; Ende, S.S.W.; Eding, E.H.; Verreth, J.A.J.

    2009-01-01

    The accumulation of substances in Recirculating Aquaculture Systems (RAS) may impair the growth and welfare of fish. To test the severity of contaminants accumulated in RAS, early-life stages of fish were used. Ultrafiltered water from two Recirculating Aquaculture Systems (RAS), one RAS with a high

  13. Flow, aeration, and carbon dioxide transfer rates for airlifts used in recirculating aquaculture systems

    Science.gov (United States)

    Airlift pumping systems reduce the electrical costs of moving water in a recirculating aquaculture system and can be concurrently designed to aerate water and remove carbon dioxide. This study determined the water flow, oxygen transfer, and CO2 removal rates for water using airlift technology in a 1...

  14. End-of-pipe single-sludge denitrification in pilot-scale recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Suhr, Karin Isabel; Pedersen, Lars-Flemming; Nielsen, J.L.

    2014-01-01

    A step toward environmental sustainability of recirculat aquaculture systems (RAS) is implementation ofsingle-sludge denitrification, a process eliminating nitrate from the aqueous environment while reduc-ing the organic matter discharge simultaneously. Two 1700 L pilot-scale RAS systems each...

  15. Nitrate removal effectiveness of fluidized sulfur-based autotrophic denitrification biofilters for recirculating aquaculture systems

    Science.gov (United States)

    There is a need to develop practical methods to reduce nitrate -nitrogen loads from recirculating aqua-culture systems to facilitate increased food protein production simultaneously with attainment of water quality goals. The most common wastewater denitrification treatment systems utilize methanol-...

  16. Optimization of blue mussel (Mytilus edulis) seed culture using recirculation aquaculture systems

    NARCIS (Netherlands)

    Blanco Garcia, A.; Kamermans, P.

    2015-01-01

    By introducing recirculation aquaculture systems (RAS) in the nursery phase of the blue mussel (Mytilus edulis) (17–18 mm), we aimed at a similar growth and survival and a similar water quality compared to the commonly used flow-through systems (FTS). To calculate water flow and size of the biofilte

  17. Comparison of phytoplankton communities in catfish split-pond aquaculture systems with conventional ponds.

    Science.gov (United States)

    There has been a growing interest and use of variations of partitioned aquaculture systems (PAS) in recent years by the southeastern United States of America farmed catfish industry. Split-pond systems, one type of PAS, are designed to better manage fish waste byproducts (e.g., ammonia) and dissolv...

  18. Fate of water borne therapeutic agents and associated effects on nitrifying biofilters in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    experience is limited. The two main objectives of this Ph.D. project were to 1) investigate the fate of FA in nitrifying aquaculture biofilters, focusing on factors influencing degradation rates, and 2) investigate the fate of HP and PAA in nitrifying aquaculture biofilters and evaluate the effects...... of these agents on biofilter nitrification performance. All experiments were conducted through addition of chemical additives to closed pilot scale recirculating aquaculture systems (RAS) with fixed media submerged biofilters under controlled operating conditions with rainbow trout (Oncorhynchus mykiss......) in a factorial design with true replicates. Biofilter nitrification performances were evaluated by changes in chemical processes, and nitrifying populations were identified by fluorescence in situ hybridisation (FISH) analysis. FA was degraded at a constant rate immediately after addition, and found...

  19. Microbial communities of recirculating aquaculture facilities: interaction between heterotrophic and autotrophic bacteria and the system itself

    OpenAIRE

    Michaud, Luigi

    2007-01-01

    Les systèmes d'aquaculture en circuit recirculé (Recirculating Aquaculture Systems, RAS) peuvent être considérés comme une alternative à la technologie de l'aquaculture en milieu ouvert et en bassins (en consommant moins d'eau pour un même rendement de production) ou peuvent être intégrés dans une chaîne de production avec des systèmes d'enclos en filet. L'intérêt des RAS est dû à leurs avantages intrinsèques comme la réduction des besoins en surface et en eau, le haut niveau de contrôle e...

  20. Low-dose hydrogen peroxide application in closed recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Good, C.; Pedersen, Per Bovbjerg

    2012-01-01

    The aim of the present work was to simulate water treatment practices with hydrogen peroxide (HP) in recirculating aquaculture systems (RAS). Six identical 1,700-L pilot-scale RAS were divided into two experimental groups based on daily feed allocation and operated under constant conditions...... and contradict prevailing notions that HP cannot be used safely in RAS that employ biofiltration. The development of effective new HP treatment protocols for recirculating aquaculture could reduce the current dependence on formalin to improve water quality and control parasitic loads...

  1. Mass transfer coefficients for carbon dioxide and oxygen for a polygeyser biofilter using airlift in an aquaculture reuse system

    Science.gov (United States)

    Aquaculture is a rapidly growing industry, accounting for over one-third of all direct fisheries consumption. In recirculating aquaculture systems the primary technology being used is energy intensive because water must be moved continuously through the culture and treatment units to remove wastes ...

  2. ISO 14001 Environmental Management System (EMS) and Risk Assessment Application in Aquaculture

    OpenAIRE

    ATAYETER, Servet

    2014-01-01

    It is obvious that there is a strong pressure tion. In today's world, companies have to on aquaculture farms for their environmental decrease their negative impacts and show their impact on aquatic environments. Consumers commitment to the environment. An effective are also becoming more and more conscious environmental management system can help a about environmental issues and clean produccompany as an administrative tool.

  3. Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    Science.gov (United States)

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

  4. Disinfection of water in recirculating aquaculture systems with peracetic acid (PAA)

    Science.gov (United States)

    The disinfection behaviour of peracetic acid (PAA) in recirculating aquaculture systems (RAS) was investigated. Peracetic acid is a strong oxidizing agent found in various concentrations in different products. Three Wofasteril PAA products (E400 (c), Lspecical; AC 150) were tested in vitro for the...

  5. Recent advances within intensive Recirculated Aquaculture System cultivation of the calanoid copepod Acartia tonsa (Dana)

    DEFF Research Database (Denmark)

    Jepsen, Per Meyer; Højgaard, Jacob Kring; Drillet, Guillaume;

    2014-01-01

    and the nauplii can be feed to marine fish larvae. A restriction is that copepod cultures for producing eggs are after 30 years of research still not stable and in large enough scale for bulk production of eggs. Recently a unique copepod Recirculated Aquaculture System (RAS) at Roskilde University (Denmark...

  6. Effects of feed loading on nitrogen balances and fish performance in replicated recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Suhr, Karin Isabel; Dalsgaard, Anne Johanne Tang;

    2012-01-01

    This study investigated the effects of applying four fixed feed loadings to three replicated recirculating aquaculture systems (RAS) on water quality changes, nitrogenous balances and growth performance of rainbow trout (Oncorhynchus mykiss).Feed loadings ranged from 1.6 to 6.3kgfeed/m3 make...

  7. Optimizing hydraulic retention times in denitrifying woodchip bioreactors treating recirculating aquaculture system wastewater

    Science.gov (United States)

    The performance of wood-based denitrifying bioreactors to treat high-nitrate wastewaters from aquaculture systems has not previously been demonstrated. Four pilot-scale woodchip bioreactors (approximately 1:10 scale) were constructed and operated for 268 d to determine the optimal range of design hy...

  8. Geosmin causes off-flavour in arctic charr in recirculating aquaculture systems

    Science.gov (United States)

    The “earthy” and “muddy” off-flavors in pond-reared fish are due to the presence of geosmin or 2-methylisoborneol (MIB) in the flesh of the fish. Similar off-flavors have been reported in fish raised in recirculating aquaculture systems (RAS); however, little information is available regarding the ...

  9. Particle sieve analysis for solids removal efficiency for recirculating aquaculture system components

    Science.gov (United States)

    As the aquaculture industry develops, opportunites for small-scale farms to become an integral part of the industry will become more prevalent. For small-scale operations it is important to have a system design that is efficient in water and energy use. If such operations decide to utilize recircula...

  10. Performance evaluation of pumping systems used in commercial-scale, split-pond aquaculture

    Science.gov (United States)

    Split-pond aquaculture systems have been adopted widely by United States catfish farmers as a way to improve production performance. The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two water conveyance structures. Water is circulated between the two b...

  11. HRT and nutrients affect bacterial communities grown on recirculation aquaculture system effluents

    NARCIS (Netherlands)

    Schneider, O.; Chabrillon-Popelka, M.; Smidt, H.; Haenen, O.L.M.; Sereti, V.; Eding, E.H.; Verreth, J.A.J.

    2007-01-01

    In a recirculation aquaculture system the drumfilter effluent can be used as substrate for heterotrophic bacterial production, which can be recycled as feed. Because the bacteria might contain pathogens, which could reduce its suitability as feed, it is important to characterize these communities. B

  12. BIOFILTERS IN AQUACULTURE

    OpenAIRE

    Ivo Šarić; Marina Barilo; Ana Gavrilović; Jurica Jug-Dujaković

    2010-01-01

    Recirculating aquaculture is one of the solutions to an environmentally sustainable and economically feasible aquaculture production, and can be established in either urban or rural communities. Controlled conditions enable optimal growth conditions suitable for the species in question during the whole growth process, as well as the shortening of the process itself, when compared to open uncontrolled systems. Recirculating systems are now one of the most researched fields of aquaculture, and ...

  13. Strategies to enhance the competitiveness of semi-intensive aquaculture systems in costal earth ponds: the organic aquaculture approach

    Directory of Open Access Journals (Sweden)

    Manuel Sardinha

    2014-06-01

    on the performance of seabream. Lower culture density (0.5 kg/m3 resulted in higher overall growth performance. The impact, in terms of nitrogenous (N and phosphorus (P loads, among the various scenarios were calculated and clearly reinforce the environmental sustainability of these semi-intensive production systems. The use of organic feeds does not lead to a significant enhancement of the growth performance. Therefore, the additional costs associated to feeding under organic standards, need to be incorporated in the sale price, thus requiring a targeted and differentiated marketing and distribution approach. Sociedade Piscicultura Farense Lda, as other traditional aquacultures depends on the enhancement of the natural environment, combined with production fine-tuning and product positioning, rewarding the quality of the final product. The positive effects of extensive and semi-intensive aquaculture in coastal areas, including environmental protection and restoration in areas of particular ecological interest, employment opportunity and development in rural and coastal areas are highly appealing concepts for the general community, particularly to conscious consumers.

  14. Purification Performance and Production of a Re-circulating Pond Aquaculture System Based on Paddy Field

    Directory of Open Access Journals (Sweden)

    Gu Li

    2012-10-01

    Full Text Available Developing improved aquaculture systems with a more efficient use of water and less environmental impact is becoming a crying need. A re-circulating aquaculture system consisting of paddy field and fish pond is a new culture mode due to aquaculture combing with agriculture. The present study focused on the purification capacity of the paddy field on nitrogen, phosphorus and organic matter, the fluctuation trend of water quality conditions during the whole rearing process and the culture efficacy of the main culture species of grass carp (Ctenopharyngodon idella. The results were as follows: under a flow rate of 1.4-5.5 m3/h for the recirculation treatment, the average removal rate of ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus and biochemical oxygen demand for the aquaculture effluent amounted to 40.5, 43.5, 31.9, 23.9, 20.7 and 52.4%, respectively, But the dissolved oxygen content in the rice fields increased obviously. During the whole process of fish rearing, the main physicochemical parameters of water quality for the experimental ponds were all maintained at a suitable level for the growth of the grass carp. In addition, there were significant differences (p<0.05 in DO, TSS, NH4+ -N, NO--N, BOD5 and Chl-&alpha between the experimental and control ponds. As far as the yield per unit and survival rate was concerned, the level of the experimental ponds was obviously higher than that of the control, while the feed conversion ratio displayed the opposite trend. Overall, the new aquaculture system realized the double aims of water reuse and the reduction of waste water discharge.

  15. A Decision Support System for Evaluatingquality Safety Risk Contaminated By Water Pollution in Aquaculture Pond

    Science.gov (United States)

    Tian, Dong; Li, Nan; Huang, Honghui; Fu, Zetian; Zhang, Xiaoshuan

    Water pollution is becoming the major factor damaging the sustainable development of aquaculture and the quality security of aquatic product in China. This paper introduces a decision support system for evaluating and managing quality risk contaminated by water pollution. The architecture, main components and their functions, especially a series of risk evaluation methods and models are described. At present, the system is in pilot in the city of Beijing in China. The stage achievements in developing the system are summarized.

  16. An integrated closed system for fish-plankton aquaculture in Amazonian fresh water

    OpenAIRE

    Gilles, Sylvain; Ismino, R.; Sanchez, H.; David, F.; Nunez Rodriguez, Jesus; Dugué, Rémi; Darias, Maria Jose; Römer, U.

    2014-01-01

    A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplan...

  17. Water chemistry characterization and component performance of a recirculating aquaculture system producing hybrid striped bass

    OpenAIRE

    Easter, Christopher

    1992-01-01

    Eight identical and independent pilot scale recirculating aquaculture production systems were populated with fingerling hybrid striped bass (Morone chrysops female x Morone saxatilis male). Three population densities were established with two replicates at 132 fishlm3 and three replicates each at 66 and 33 fishlm3. Water chemistry and water quality characteristics were monitored throughout the 228 day growth trial for all eight systems. A system component performance analys...

  18. A Comparative Analysis of Three Biofilter Types Treating Wastewater Produced in Recirculating Aquaculture Systems

    OpenAIRE

    Hall, Antar Gamble

    1999-01-01

    Nine recirculating systems at the Virginia Tech Aquaculture Center were placed on line and stocked with yellow perch, Perca flavescens, fingerlings. Fish were stocked at a density of approximately 455 fish m-3. Biofilter types were the only factor differing among system designs and were an upflow pulsed bed bead filter, packed tower trickling filter and a rotating biological contactor (RBC). After stocking, systems were allowed to acclimate using ammonia excreted by the yellow perch. Foll...

  19. A COMPARATIVE ANALYSIS OF THREE BIOFILTER TYPES TREATING WASTEWATER PRODUCED IN RECIRCULATING AQUACULTURE SYSTEMS

    OpenAIRE

    Hall, Antar Gamble

    2000-01-01

    Nine recirculating systems at the Virginia Tech Aquaculture Center were placed on line and stocked with yellow perch, Perca flavescens, fingerlings. Fish were stocked at a density of approximately 455 fish m-3. Biofilter types were the only factor differing among system designs and were an upflow pulsed bed bead filter, packed tower trickling filter and a rotating biological contactor (RBC). After stocking, systems were allowed to acclimate using ammonia excreted by the yellow perch. Foll...

  20. A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System

    OpenAIRE

    Francisco J. Espinosa-Faller; Guillermo E. Rendón-Rodríguez

    2012-01-01

    A ZigBee wireless sensor network was developed for monitoring an experimental aquaculture recirculating system.Temperature, dissolved oxygen, water and air pressure as well as electric current sensors were included in the setup.The high fish densities required in these systems to become economically viable present a case where sensornetworks can be applied to preserve a healthy livestock and to reduce the risk of failures that end up in the loss ofproduction. Modules for reading and transmitt...

  1. Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system

    OpenAIRE

    M. Angélica Garrido-Pereira; Michael Schwarz; Brendan Delbos; Ricardo V. Rodrigues; Luis Romano; Luís Sampaio

    2014-01-01

    Cobia (Rachycentron canadum) is a marine finfish with good potential for mariculture. This study analyzes the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS). Larvae were stocked into two independent RAS for 26 days after hatching. One of the systems (Probiotic treatment) received the addition of a commercial probiotic consisting of B. subtilis, B. licheniformis and B. pumilus directly into the water and by live feed. Su...

  2. Water quality in recirculating aquaculture systems (ras) for arctic charr (salvelinus alpinus L.) culture.

    OpenAIRE

    Isla Molleda , M.

    2008-01-01

    Recirculating aquaculture systems (RAS) for fish culture have been used for more than three decades. The interest in RAS is due to their have advantages such as greatly reduced land and water requirements in places where the water resources are limited; but the RAS have also disadvantages like the deterioration of the water quality if the water treatment processes within the system are not controlled properly. The water quality problems in RAS were associated with low DO and high fish waste m...

  3. Indicative and pathogenic microbiological quality of aquacultured finfish grown in different production systems.

    Science.gov (United States)

    Pullela, S; Fernandes, C F; Flick, G J; Libey, G S; Smith, S A; Coale, C W

    1998-02-01

    The nature and number of indicator and pathogenic microbes in fish reared using recirculating and nonrecirculating water systems were compared. For each system, 20 samples of rainbow trout (Oncorhynchus mykiss), tilapia (Oreochromis spp.), hybrid striped bass (Morone saxatilis x M. chrysops), and pacu (Piaractus mesopotamicus) were randomly selected and gutted, and microbial analyses were performed using AOAC procedures. Five fish were subsampled and analyzed for indicative microbial quality with 3M Petrifilm (). The general microbial quality differed significantly (P spp. were not isolated form the fish sampled. However, Clostridium botulinum botulinum was isolated from all the aquacultured fish sampled except pacu and tilapia grown in a recirculating aquaculture system. However, the counts were very low, ranging from 0.0 to 2.3 MPN/g. PMID:9708283

  4. A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System

    Directory of Open Access Journals (Sweden)

    Francisco J. Espinosa-Faller

    2012-06-01

    Full Text Available A ZigBee wireless sensor network was developed for monitoring an experimental aquaculture recirculating system.Temperature, dissolved oxygen, water and air pressure as well as electric current sensors were included in the setup.The high fish densities required in these systems to become economically viable present a case where sensornetworks can be applied to preserve a healthy livestock and to reduce the risk of failures that end up in the loss ofproduction. Modules for reading and transmitting sensor values through a ZigBee wireless network were developedand tested. The modules were installed in an aquaculture recirculating system to transmit sensor values to thenetwork coordinator. A monitoring program was created in order to display and store sensor values and to comparethem with reference limits. An alert is emitted in case reference limits have been reached. E-mail and an SMSmessage alert can also be sent to the cellular phone of the system administrator, so immediate action can be taken. Aweb interface allows Internet access to the sensor values. The present work demonstrates the applicability of ZigBeewireless sensor network technology to aquaculture recirculating systems.

  5. Denitrification of Recirculating Aquaculture System Waters Using an Upflow Biofilter and a Fermented Substrate

    OpenAIRE

    Phillips, Jennifer Brooke

    1997-01-01

    The ability of an upflow, denitrifying biofilter using a fermentation generated carbon source to treat the high nitrate concentrations typically seen in recirculating aquaculture systems was studied using a synthetic nitrate wastewater supplied at two nitrate loadings, 1.13 and 2.52 kg NO3-N/m3/day. A supplemental carbon source was provided primarily through the fermentation of fish food which generated volatile fatty acids (VFA) in the form of acetic, propionic, isobutyric, n-butyric, 2-me...

  6. Phylogenetic characterization of the heterotrophic bacterial communities inhabiting a marine recirculating aquaculture system

    OpenAIRE

    Michaud, L; Lo Giudice, A; Troussellier, Marc; Smedile, F; Bruni, V.; Blancheton, J. P.

    2009-01-01

    Aims: The aim of the present work was to characterize the heterotrophic bacterial community of a marine recirculating aquaculture system (RAS). Methods and Results: An experimental RAS was sampled for the rearing water (RW) and inside the biofilter. Samples were analysed for bacterial abundances, community structure and composition by using a combination of culture-dependent and -independent techniques. The most represented species detected among biofilter clones was Pseudomonas stutzeri, whi...

  7. Assessement of Growth Performances of Juvenile Sterlet Acipenser ruthenus Raised in a Recirculating Aquaculture System (RAS)

    OpenAIRE

    Mărioara Nicula; Zoltan-Tibor Szelei; Nicolae Pacala; Marian Bura; Eliza Simiz; Silvia Erina; Marian Hotea; Adela Marcu

    2015-01-01

    The study was conducted within the recirculating aquaculture system for sturgeon rearing in Herneacova village, Timis County, on a population of juvenile sterlet (Acipenser ruthenus) aged between 346-431 days. Specimens were housed in five round tanks (Ø=3 m, V=6 m3, h=100 cm) and fed with commercial extruded pellets (3 mm granulation, 48% CP, and 10% EE). Fish from each tank were individually weighed and measured once every two weeks. Bioproductive indices such body weight gain (BW), specifi...

  8. The technical development and application of a recirculating aquaculture respirometer system (RARS) for fish metabolism studies

    OpenAIRE

    Stiller, Kevin Torben

    2016-01-01

    In dieser Arbeit wurde ein Recirculating Aquaculture Respirometre System (RARS) technisch entwickelt und die Einsatzmöglichkeiten in verschiedenen metabolischen Studien an Fischen unter Einbeziehung der Futtermittelverwertung evaluiert. Kapitel 1 stellt das RARS und die eingebauten online Messgeräte vor. Die Funktionalität des RARS wurde durch einige Beispielmessungen an Regenbogenforellen (Oncorhynchus mykiss) und Steinbutt, (Scophthalmus maximus) gezeigt. Im Kapitel 2 wurden über 8 W...

  9. An economic analysis of the use of recirculating aquaculture systems in the production of Tilapia

    OpenAIRE

    Appiah-Kubi, Frank

    2012-01-01

    An economic analysis of tilapia production was conducted using a recirculating aquaculture system facility, situated at the Norwegian University of Life Science (UMB). The goals were; (1) to evaluate and estimate the operational cost involved and from this, estimate the breakeven cost, (2) identify and describe the constraints unique to the RAS, (3) to perform financial feasibility of a (hypothetical) scale-up production, and (4) to conduct sensitivity analysis on some variables to highlight ...

  10. Conditioning of broodstock of tiger grouper, Epinephelus fuscoguttatus, in a recirculating aquaculture system

    OpenAIRE

    Saleem Mustafa; Mohd. Hafizzie Hajini; Shigeharu Senoo; Annita Yong Seok Kian

    2015-01-01

    Closing the cycle of commercial species of fish in a recirculating aquaculture system is gaining importance for a number of practical advantages. Founder broodstock originating from the wild population is conditioned to live in hatchery tanks under suitable environmental and feeding conditions and is induced to breed. The juveniles are grown to maturity and facilitated to spawn in captivity to close the life cycle in the hatchery. This experiment was carried out on tiger grouper (Epinephelus ...

  11. Observations on Side-Swimming Rainbow Trout in Water Recirculation Aquaculture Systems

    OpenAIRE

    Good, Christopher; Davidson, John; Kinman, Christin; Kenney, P. Brett; Bæverfjord, Grete; Summerfelt, Steven

    2014-01-01

    Abstract During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRASs), it was observed that Rainbow Trout Oncorhynchus mykiss in all WRASs exhibited a higher-than-normal prevalence of side swimming (i.e., controlled, forward swimming but with misaligned orientation such that the fish's sagittal axis is approximately parallel to the horizontal plane). To further our understanding of this abnormality, a substudy was conducted wherein side swimmers and n...

  12. Integration of aquaculture and agriculture: a route to sustainable farming systems

    OpenAIRE

    Lightfoot, C. (eds.)

    1990-01-01

    The integration of agriculture and aquaculture as a means of intensifying resource use and improving the productivity of many current farming practices in Southeast Asian and African countries is discussed. A brief account is given of work undertaken by ICLARM in Malawi and India regarding the improved use of marginal lands to integrate crops, vegetables, trees, livestock and fish, outlining also the various problems involved in the extension of such integrated fish farming systems.

  13. In situ estimation of water quality parameters in freshwater aquaculture ponds using hyperspectral imaging system

    Science.gov (United States)

    Abd-Elrahman, Amr; Croxton, Matthew; Pande-Chettri, Roshan; Toor, Gurpal S.; Smith, Scot; Hill, Jeffrey

    Knowledge of water quality parameters is integral to sustainability of freshwater aquaculture operations that raise ornamental fish. Our objective in this study is to evaluate the ability of a mobile, ground-based hyperspectral (HS) imaging sensor to determine chlorophyll-a (Chl-a) concentrations in working aquaculture ponds, which represent manipulated, shallow, nutrient-rich systems, and to determine the effect of using submerged reflectance targets on the accuracy of Chl-a estimation. We collected Chl-a measurements from aquaculture ponds ranging from 0.8 to 494 μg/L. Chl-a measurements showed a strong correlation with two-band and three-band spectral indices computed from the HS image reflectance. Coefficient of determination ( R2) values of 0.975 and 0.982 were obtained for the two- and three-band models, respectively, using spectra captured from the submerged target at 10 cm depth. Using spectra captured from water (no submerged targets), R2 values were slightly lower at 0.833 and 0.862 for two- and three-band models. Data from the submerged target at 30 cm depth had the lowest correlation with measured chlorophyll-a concentrations, potentially due to variations in water column properties and shadows cast by the platform. Modeling total Phosphorous (P) and Nitrogen (N) concentrations of the collected samples with the spectral indices sensitive to Chl-a concentrations showed a moderate level of correlation. Removing a model outlier (observation with maximum N and P concentrations) led to a significant increase in the models' coefficient of determination ( e.g. from 0.478 to 0.823 for the P model using three-band index values), which highlighted the possibility of using HS imagery to estimate N and P concentrations and the need for more research to model the interrelationships between Chl-a and nutrient concentrations in aquaculture water systems.

  14. The OMEGA system for marine bioenergy, wastewater treatment, environmental enhancement, and aquaculture

    Science.gov (United States)

    Trent, J. D.

    2013-12-01

    OMEGA is an acronym for Offshore Membrane Enclosure for Growing Algae. The OMEGA system consists of photobioreactors (PBRs) made of flexible, inexpensive clear plastic tubes attached to floating docks, anchored offshore in naturally or artificially protected bays [1]. The system uses domestic wastewater and CO2 from coastal facilities to provide water, nutrients, and carbon for algae cultivation [2]. The surrounding seawater maintains the temperature inside the PBRs and prevents the cultivated (freshwater) algae from becoming invasive species in the marine environment (i.e., if a PBR module accidentally leaks, the freshwater algae that grow in wastewater cannot survive in the marine environment). The salt gradient between seawater and wastewater is used for forward osmosis (FO) to concentrate nutrients and facilitate algae harvesting [3]. Both the algae and FO clean the wastewater, removing nutrients as well as pharmaceuticals and personal-care products [4]. The offshore infrastructure provides a large surface area for solar-photovoltaic arrays and access to offshore wind or wave generators. The infrastructure can also support shellfish, finfish, or seaweed aquaculture. The economics of the OMEGA system are supported by a combination of biofuels production, wastewater treatment, alternative energy generation, and aquaculture. By using wastewater and operating offshore from coastal cities, OMEGA can be located close to wastewater and CO2 sources and it can avoid competing with agriculture for water, fertilizer, and land [5]. By combining biofuels production with wastewater treatment and aquaculture, the OMEGA system provides both products and services, which increase its economic feasibility. While the offshore location has engineering challenges and concerns about the impact and control of biofouling [6], large OMEGA structure will be floating marine habitats and will create protected 'no-fishing' zones that could increase local biodiversity and fishery

  15. Aquaculture in bio-regenerative life support systems (BLSS): Considerations

    Science.gov (United States)

    Gonzales, John M.

    2009-04-01

    A significant amount of research has been invested into understanding the effects of including fish culture in bio-regenerative life support systems (BLSS) for long duration space habitation. While the benefits of fish culture as a sub-process for waste treatment and food production continue to be identified, other pressing issues arise that affect the overall equivalent system mass associated with fish culture in a BLSS. This paper is meant to provide insight into several issues affecting fish culture in a BLSS that will require attention in the future if fish meant for consumption are to be cultured in a BLSS.

  16. Use of Barley for the Purification of Aquaculture Wastewater in a Hydroponics System

    Directory of Open Access Journals (Sweden)

    A. M. Snow

    2008-01-01

    Full Text Available Barley was examined for its ability to remove nutrients from aquaculture wastewater. The effects of seed sterilization using ethanol and bleach and seed density on germination and plant growth were investigated. Surface sterilization of barley seeds had a negative impact on germination. Increasing the ethanol concentration and/or the bleach concentration reduced the germination percentage. Barley seeds were first germinated in water in the hydroponics system. The seedlings then received wastewater from an aquaculture system stocked with Arctic charr. During the experiment, the crops grew rapidly and fairly uniformly and showed no signs of mineral deficiency or disease. The average crop height at harvest was 25.5 cm and the yield varied from 25 to 59 t haˉ1, depending on the seed density. The hydroponically grown barley was able to significantly reduce the pollution load of the aquaculture wastewater. The TS, COD, NH4+-N, NO2--N, NO3--N, and PO43--P reductions ranged from 52.7 to 60.5%, from 72.9 to 83.1%, from 76.0 to 76.0%, from 97.6 to 99.2%, from 76.9 to 81.6% and from 87.1 to 95.1%, respectively. However, the effluent produced from the hydroponics system had slightly higher levels of TS (420-485 mg Lˉ1 than the 480 mg Lˉ1 recommended for aquatic animals. A sedimentation/filtration unit should be added to the hydroponics system.

  17. Particle size distribution in the tilapia Recirculating Aquaculture System

    OpenAIRE

    Stokic, Jelena

    2012-01-01

    This study was to evaluate methods for measuring and describing particle size distribution from three different spots in Tilapia recirculating system at University of Life Ccience in Ås, Norway. For this purpose serial filtration over different mesh size and parallel filtration over different mesh size methods were compared. Water samples were taken from before drum filter, after drum filter and after bio-filter (MBBR) and filtrated through eight different mesh size classes and calculated in ...

  18. Mathematical modelling of nutrient balance of a goldfish (Carassius auratus Linn.) recirculating aquaculture system (GRAS)

    OpenAIRE

    Sudeep Puthravilakom Sadasivan Nair; Sanjib Moulick; Chanchal Kumar Mukherjee; Mohd Tanveer

    2010-01-01

    In the present study, a goldfish (Carassius auratus Linn.) recirculating aquaculture system (GRAS) has been developed. The GRAS consisted of a culture tank, a screen filter and a foam fractionator for removal of particulate and dissolved solids and a trickling filter for conversion of ammonium- and nitrite-nitrogen to relatively harmless nitrate-nitrogen. The culture of goldfish at a stocking density of 1.08 kg/m3 was continued for a period of two and half months. Based on mass balance analys...

  19. The influence of pellets quality on the growth of sterlet, in recirculating aquaculture system

    OpenAIRE

    Corina Sion; Petronela G. Călin; Lucian Oprea; Aurelia Nica; Gianina M. Băcanu

    2011-01-01

    The paper presents some aspects regarding the influence of food quality on the breeding of sterlet, Acipenser ruthenus Linnaeus, 1758, in a recirculating aquaculture system (RAS). The experiment took place over 30 days, in four pilot breeding units type aquaria of 300 liters in volume. Two kind of variants were compared, with repetition, V1 with 46% crude protein and V2 with 30% crude protein, respectively. The stocking density was of 14 fish/unit. The same feeding level of 8 g/kg metabolic w...

  20. Removal efficiency and balance of nitrogen in a recirculating aquaculture system integrated with constructed wetlands.

    Science.gov (United States)

    Zhong, Fei; Liang, Wei; Yu, Tao; Cheng, Shui P; He, Feng; Wu, Zhen B

    2011-01-01

    The nitrogen (N) balance for aquaculture is an important aspect, especially in China, and it is attributed to the eutrophication in many freshwater bodies. In recent years, constructed wetlands (CWs) have been widely used in wastewater treatment and ecosystem restoration. A recirculating aquaculture system (RAS) consisting of CWs and 4 fish ponds was set up in Wuhan, China. Channel catfish (Ictalurus punctatus) fingerlings were fed for satiation daily for 168 days with 2 diets containing 5.49 % and 6.53 % nitrogen, respectively. The objectives of this study were to investigate the N budget in the RAS, and try to find out the feasibility of controlling N accumulation in the fish pond. It is expected that the study can provide a mass balance for the fate of N in the eco-friendly treatment system to avoid eutrophication. The results showed that the removal rates of ammonia (NH(+)(4)-N), sum of nitrate & nitrite (NO(-)(X)-N), and total nitrogen (TN) by the CWs were 20-55%, 38-84 % and 39-57 %, respectively. Denitrification in the CWs was the main pathway of nitrogen loss (41.67 %). Nitrogen accumulation in pond water and sediment accounted for 3.39 % and 12.65 % of total nitrogen loss, respectively. The nitrogen removal efficiency and budget showed that the CW could be used to control excessive nitrogen accumulation in fish ponds. From the viewpoint of the nitrogen pollution control, the RAS combined with the constructed wetland can be applied to ensure the sustainable development for aquaculture. PMID:21644158

  1. Program to monitor and evaluate a passive solar greenhouse/aquaculture system. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    A temperature monitoring program of Amity's solar greenhouse demonstrated that air, soil, and water temperatures can be maintained at optimal levels without supplemental heat. A foil reflector placed in front of the greenhouse glazing at an angle of between 0 and 5/sup 0/ above horizontal enhanced direct light entering the greenhouse by as much as 22%. Aquaculture in the water heat storage of a solar greenhouse has been a success. Fish reached harvest size in about seven months. The two species that were received the best by the public were African perch (Tilapia mossambica) and channel catfish (Ictalurus punctatus). Although carp (Cyprinus carpio) were the fastest growers they were not well received by the public. Linking hydroponics to greenhouse aquaculture shows a lot of promise. Different support medias were examined and tomatoes and European cucumbers were raised successfully. A savonius windmill was successfully linked to an aquaculture aeration system but because of the wind pattern in the Willamette valley the windmill system did not provide air in the evening when it was needed most. Alternate designs are discussed. Locally grown fish diets were evaluated for their ability to promote fish growth. Diets such as water hyacinth, duckweed, earthworms, beans, and comfrey were raised on the Amity site, pelleted with a hand grinder and solar dried. Duckweed and earthworms appear to hold promise for a nutritous, easy to grow and pelletize, food source. Amity's solar greenhouse, three coldframe designs and a PVC tunnel cloche were compared in a vegetable growing trial. Most impressive was the cloche design because it provided adequate protection, was inexpensive and very easy to build.

  2. Nitrification in brackish water recirculating aquaculture system integrated with activated packed bed bioreactor.

    Science.gov (United States)

    Rejish Kumar, V J; Joseph, Valsamma; Philip, Rosamma; Bright Singh, I S

    2010-01-01

    Recirculation aquaculture systems (RAS) depend on nitrifying biofilters for the maintenance of water quality, increased biosecurity and environmental sustainability. To satisfy these requirements a packed bed bioreactor (PBBR) activated with indigenous nitrifying bacterial consortia has been developed and commercialized for operation under different salinities for instant nitrification in shrimp and prawn hatchery systems. In the present study the nitrification efficiency of the bioreactor was tested in a laboratory level recirculating aquaculture system for the rearing of Penaeus monodon for a period of two months under higher feeding rates and no water exchange. Rapid setting up of nitrification was observed during the operation, as the volumetric total ammonia nitrogen removal rates (VTR) increased with total ammonia nitrogen (TAN) production in the system. The average Volumetric TAN Removal Rates (VTR) at the feeding rate of 160 g/day from 54-60th days of culture was 0.1533+/-0.0045 kg TAN/m(3)/day. The regression between VTR and TAN explained 86% variability in VTR (P<0.001). The laboratory level RAS demonstrated here showed high performance both in terms of shrimp biomass yield and nitrification and environmental quality maintenance. Fluorescent in-situ Hybridization analysis of the reactor biofilm ensured the presence of autotrophic nitrifier groups such as Nitrosococcus mobilis lineage, Nitrobacter spp and phylum Nitrospira, the constituent members present in the original consortia used for activating the reactors. This showed the stability of the consortia on long term operation. PMID:20150717

  3. Characterising organic matter in recirculating aquaculture systems with fluorescence EEM spectroscopy.

    Science.gov (United States)

    Hambly, A C; Arvin, E; Pedersen, L-F; Pedersen, P B; Seredyńska-Sobecka, B; Stedmon, C A

    2015-10-15

    The potential of recirculating aquaculture systems (RAS) in the aquaculture industry is increasingly being acknowledged. Along with intensified application, the need to better characterise and understand the accumulated dissolved organic matter (DOM) within these systems increases. Mature RASs, stocked with rainbow trout and operated at steady state at four feed loadings, were analysed by dissolved organic carbon (DOC) analysis and fluorescence excitation-emission matrix (EEM) spectroscopy. The fluorescence dataset was then decomposed by PARAFAC analysis using the drEEM toolbox. This revealed that the fluorescence character of the RAS water could be represented by five components, of which four have previously been identified in fresh water, coastal marine water, wetlands and drinking water. The fluorescence components as well as the DOC showed positive correlations with feed loading, however there was considerable variation between the five fluorescence components with respect to the degree of accumulation with feed loading. The five components were found to originate from three sources: the feed; the influent tap water (groundwater); and processes related to the fish and the water treatment system. This paper details the first application of fluorescence EEM spectroscopy to assess DOM in RAS, and highlights the potential applications of this technique within future RAS management strategies. PMID:26141427

  4. Predictive model of food intake of the Seabass Dicentrarchus labrax in closed aquaculture systems

    Directory of Open Access Journals (Sweden)

    Allan T Souza

    2015-12-01

    Full Text Available Fish feeding is the main source of waste in aquaculture and is also responsible for most of the environmental impacts derived from this activity. The European Seabass Dicentrarchus labrax is one of the most farmed fishes in the continent, generating an important load of waste on the environment. The consumption of food in fishes is highly dependent on the water temperature and salinity, which create a source of variability on the amount of the ration consumed by fishes. This issue is often neglected by farmers, which aggravates the ration waste. The use of models in aquaculture is increasing in the recent years, and is an excellent tool to combine an increased production with the mitigation of environmental impacts. In this context, this study aimed at developing a predictive model of the D. labrax consumption rate in closed aquaculture systems. Based on the literature review we were able to develop a conceptual diagram and a prototype of the model using the STELLA software (isee®. The preliminary results indicated that the model was capable of predicting the ration consumption of the D. labrax according to the oscillations in the water temperature and salinity. The consumption rate and growth were higher at 21ºC and with a salinity of 28 psu. Laboratory assays are need to validate the models outputs, and they are scheduled to start in October 2015. Finally, the model’s structure, equations, inputs and outputs were integrated into an easy-to-use software developed by the FoodInTech® company, that will help farmers to increase their yields and reduce the waste of ration and the nutrient load on the environment.

  5. Daily micro particle distribution of an experimental recirculating aquaculture system – A case study

    DEFF Research Database (Denmark)

    Fernandes, Paulo; Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg

    2014-01-01

    The particle size distribution (PSD) in a recirculating aquaculture system (RAS) was investigated duringa 24-h cycle. PSD was analyzed in water sampled at several locations in a recirculation loop containing a60-m drum filter, a submerged fixed-bed biofilter and a trickling filter.In relation...... to total counts, the system was dominated by micro-particles with particles smaller than20 m comprising >94% of the distribution in all samples. However, the system presented a substantialvolumetric influence of larger particles, reflected by a PSD derivate ˇ-value of 3.40 ± 0.18. Overall ˇ......-valuesthroughout the compartments (p = 0.584) and experimental period (p = 0.217) were not significantlydifferent, although specific components seemed to marginally affect the PSD.A high internal water turnover rate (one system passage every 50 min) promoted the rapid removalof large particles from the system. Permanent volumetric...

  6. Assessement of Growth Performances of Juvenile Sterlet Acipenser ruthenus Raised in a Recirculating Aquaculture System (RAS

    Directory of Open Access Journals (Sweden)

    Mărioara Nicula

    2015-10-01

    Full Text Available The study was conducted within the recirculating aquaculture system for sturgeon rearing in Herneacova village, Timis County, on a population of juvenile sterlet (Acipenser ruthenus aged between 346-431 days. Specimens were housed in five round tanks (Ø=3 m, V=6 m3, h=100 cm and fed with commercial extruded pellets (3 mm granulation, 48% CP, and 10% EE. Fish from each tank were individually weighed and measured once every two weeks. Bioproductive indices such body weight gain (BW, specific growth rate (SGR, and feed conversion ratio (FCR were calculated at the end of an 85 days experimental period. Statistical analysis was performed using the SPPS IBM 22 and Minitab 16 software. Data were reported as Mean±Sx at a significant level of p<0.05. Testing differences between means was realized by ANOVA completed with post-hoc Tukey test. The results obtained indicate that the growth performance of juvenile Acipenser ruthenus seems to be similar and even better than that of other sturgeons species reared in recirculating aquaculture system.

  7. Determination of oxytetracycline residues in matrixes from a freshwater recirculating aquaculture system.

    Science.gov (United States)

    Carson, Mary C; Bullock, Graham; Bebak-Williams, Julie

    2002-01-01

    This paper describes related procedures to determine the amount of oxytetracycline (OTC) present in trout tissue (muscle with skin attached), biofilter sand, sediment, and tank water from a recirculating aquaculture system. OTC was extracted from the matrixes by different techniques, depending on complexity of the matrix and desired OTC detection level in that matrix. Listed in order of increasing complexity, OTC was extracted from tank water by dilution with acidic buffer containing ethylenediaminetetraacetic acid (EDTA); from biofilter sand by shaking with 0.1 N HCl; from sediment by homogenization and shaking with buffer/EDTA; and from ground trout by homogenization and shaking with buffer/EDTA (twice), with further cleanup and concentration of the extract on a polymeric solid-phase extraction cartridge. The 4 procedures all used the same reversed-phase gradient chromatography on a polymeric column with UV detection at 350 nm. The lower limit of detection (estimated) and upper limit of validation for each of these 4 matrixes were 0.04-4.0 microg/g (ppm; trout), 0.03-20 ppm (biofilter sand), 1-6000 ppm (sediment), and 0.003-10 ppm (water). Recoveries ranged from 82 to 108%, with relative standard deviation recirculating aquaculture system. PMID:11990017

  8. Environmental quality and aquaculture systems: Proceedings of the Thirteenth U.S.-Japan Meeting on Aquaculture, Mie, Japan, October 24-25, 1984

    OpenAIRE

    1988-01-01

    The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the United States-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries. The UJNR was begun during t...

  9. Sewage treatment in integrated system of UASB reactor and duckweed pond and reuse for aquaculture.

    Science.gov (United States)

    Mohapatra, D P; Ghangrekar, M M; Mitra, A; Brar, S K

    2012-06-01

    The performance of a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and a duckweed pond containing Lemna gibba was investigated for suitability for treating effluent for use in aquaculture. While treating low-strength sewage having a chemical oxygen demand (COD) of typically less than 200 mg/L, with an increase in hydraulic retention time (HRT) from 10.04 to 33.49 h, COD removal efficiency of the UASB reactor decreased owing to a decrease in organic loading rate (OLR) causing poor mixing in the reactor. However, even at the lower OLR (0.475 kg COD/(m3 x d)), the UASB reactor gave a removal efficiency of 68% for COD and 74% for biochemical oxygen demand (BOD). The maximum COD, BOD, ammonia-nitrogen and phosphate removal efficiencies of the duckweed pond were 40.77%, 38.01%, 61.87% and 88.57%, respectively. Decreasing the OLR by increasing the HRT resulted in an increase in efficiency of the duckweed pond for removal of ammonia-nitrogen and phosphate. The OLR of 0.005 kg COD/(m2 x d) and HRT of 108 h in the duckweed pond satisfied aquaculture quality requirements. A specific growth rate of 0.23% was observed for tilapia fish fed with duckweed harvested from the duckweed pond. The economic analysis proved that it was beneficial to use the integrated system of a UASB reactor and a duckweed pond for treatment of sewage. PMID:22856320

  10. Integrated fish-seaweed cultivation in recirculating aquaculture systems: objectives and preliminary results of "IntegRAS" project

    OpenAIRE

    Oca Baradad, Joan; Pintado Valverde, José; Cremades Ugarte, Javier; Masaló Llorà, Ingrid; Ruiz, Patricia; Alamrousi, A; Jiménez de Ridder, Patrícia; Machado, Samuel; Reig Puig, Lourdes

    2015-01-01

    Recirculating aquaculture systems (RAS) allow minimizing the water renewal flow rate needed in fish production by increased Nitrogen (NO3 ) and Phosphorous concentrations. Integrating seaweed production to RAS can improve its performances and reduce soluble wastes, contributing to a more sustainable production system.

  11. Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    M. Angélica Garrido-Pereira

    2014-11-01

    Full Text Available Cobia (Rachycentron canadum is a marine finfish with good potential for mariculture. This study analyzes the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS. Larvae were stocked into two independent RAS for 26 days after hatching. One of the systems (Probiotic treatment received the addition of a commercial probiotic consisting of B. subtilis, B. licheniformis and B. pumilus directly into the water and by live feed. Survival, final weight and water quality were not affected by probiotics. Results showed larvae of the probiotic treatment demonstrated a greater resistance to salinity stress. Immunohistochemical analysis showed a higher expression of CD4 in probiotic treatment. These results suggest that Bacillus spp. probiotics used in RAS have a potential stimulating impact on immune system differentiation and increases salinity stress resistance of cobia larvae.

  12. The influence of different stocking densities on biochemical composition of rainbow trout meat reared in a recirculating aquaculture system

    OpenAIRE

    Mirela Cretu; Cristea Victor; Dediu Lorena; Petrea Stefan Mihai

    2014-01-01

    The aim of this study is to evaluate the biochemical composition of rainbow trout meat, reared in a recirculating aquaculture system, at different stocking densities (DS1-2,64 kg/m3, DS2-5,16 kg/m3, DS3-7,12 kg/m3, DS4-9,42 kg/m3). The analyses were performed in the research laboratory of Aquaculture, Environmental Science and Cadastre Department – Faculty of Food Science and Engineering, from ,,Dunarea de Jos’’University of Galati. The content of meat proteins, fats, dry substance and ash wa...

  13. The potential use of constructed wetlands in a recirculating aquaculture system for shrimp culture

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Y.-F.; Jing, S.-R.; Lee, D.-Y

    2003-05-01

    Constructed wetlands improved water qualities and consequently increased the shrimp growth and survival in a recirculating system. - A pilot-scale constructed wetland unit, consisting of free water surface (FWS) and subsurface flow (SF) constructed wetlands arranged in series, was integrated into an outdoor recirculating aquaculture system (RAS) for culturing Pacific white shrimp (Litopenaeus vannamei). This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of improvement in water quality of the culture tank on the growth and survival of shrimp postlarvae. During an 80-day culture period, the wetland unit operated at a mean hydraulic loading rate of 0.3 m/day and effectively reduced the influent concentrations of 5-day biochemical oxygen demand (BOD{sub 5}, 24%), suspended solids (SS, 71%), chlorophyll a (chl-a, 88%), total ammonium (TAN, 57%), nitrite nitrogen (NO{sub 2}-N, 90%) and nitrate nitrogen (NO{sub 3}-N, 68%). Phosphate (PO{sub 4}-P) reduction was the least efficient (5.4%). The concentrations of SS, Chl-a, turbidity and NO{sub 3}-N in the culture tank water in RAS were significantly (P{<=}0.05) lower than those in a control aquaculture system (CAS) that simulated static pond culture without wetland treatment. However, no significant difference (P{<=}0.05) in BOD{sub 5}, TAN and NO{sub 2}-N was found between the two systems. At the end of the study, the harvest results showed that shrimp weight and survival rate in the RAS (3.8{+-}1.8 g/shrimp and 90%) significantly (P{<=}0.01) exceeded those in the CAS (2.3{+-}1.5 g/shrimp and 71%). This study concludes that constructed wetlands can improve the water quality and provide a good culture environment, consequently increasing the shrimp growth and survival without water exchange, in a recirculating system.

  14. A highly sensitive underwater video system for use in turbid aquaculture ponds.

    Science.gov (United States)

    Hung, Chin-Chang; Tsao, Shih-Chieh; Huang, Kuo-Hao; Jang, Jia-Pu; Chang, Hsu-Kuang; Dobbs, Fred C

    2016-01-01

    The turbid, low-light waters characteristic of aquaculture ponds have made it difficult or impossible for previous video cameras to provide clear imagery of the ponds' benthic habitat. We developed a highly sensitive, underwater video system (UVS) for this particular application and tested it in shrimp ponds having turbidities typical of those in southern Taiwan. The system's high-quality video stream and images, together with its camera capacity (up to nine cameras), permit in situ observations of shrimp feeding behavior, shrimp size and internal anatomy, and organic matter residues on pond sediments. The UVS can operate continuously and be focused remotely, a convenience to shrimp farmers. The observations possible with the UVS provide aquaculturists with information critical to provision of feed with minimal waste; determining whether the accumulation of organic-matter residues dictates exchange of pond water; and management decisions concerning shrimp health. PMID:27554201

  15. Modelling for an improved integrated multi-trophic aquaculture system for the production of highly valued marine species

    Directory of Open Access Journals (Sweden)

    Luana Granada

    2014-05-01

    Full Text Available Integrated multi-trophic aquaculture (IMTA is regarded as a suitable approach to limit aquaculture nutrients and organic matter outputs through biomitigation. Here, species from different trophic or nutritional levels are connected through water transfer. The co-cultured species are used as biofilters, and each level has its own independent commercial value, providing both economic and environmental sustainability. In order to better understand and optimize aquaculture production systems, dynamic modelling has been developed towards the use of models for analysis and simulation of aquacultures. Several models available determine the carrying capacity of farms and the environmental effects of bivalve and fish aquaculture. Also, in the last two decades, modelling strategies have been designed in order to predict the dispersion and deposition of organic fish farm waste, usually using the mean settling velocity of faeces and feed pellets. Cultured organisms growth, effects of light and temperature on algae growth, retention of suspended solids, biodegradation of nitrogen and wastewater treatment are examples of other modelled parameters in aquaculture. Most modelling equations have been developed for monocultures, despite the increasing importance of multi-species systems, such as polyculture and IMTA systems. The main reason for the development of multi-species models is to maximize the production and optimize species combinations in order to reduce the environmental impacts of aquaculture. Some multi-species system models are available, including from the polyculture of different species of bivalves with fish to more complex systems with four trophic levels. These can incorporate ecosystem models and use dynamic energy budgets for each trophic group. In the proposed IMTA system, the bioremediation potential of the marine seaweed Gracilaria vermiculophylla (nutrient removal performance and the Mediterranean filter-feeding polychaete Sabella

  16. The role of a fish pond in optimizing nutrient flows in integrated agriculture-aquaculture farming systems

    NARCIS (Netherlands)

    Nhan, D.K.

    2007-01-01

      In the Mekong delta, the Vietnamese government promoted integrated agriculture-aquaculture (IAA) farming systems as an example of sustainable agriculture. An important advantage of IAA-farming is the nutrient linkage between the pond and terrestrial components within a f

  17. Abnormal swimming behavior and increased deformities in rainbow trout Oncorhynchus mykiss cultured in low exchange water recirculation aquaculture systems

    Science.gov (United States)

    Two studies were conducted to determine if accumulating water quality parameters would negatively impact rainbow trout Oncorhynchus mykiss health and welfare within water recirculation aquaculture systems (WRAS) that were operated at low and near-zero water exchange, with and without ozonation, and ...

  18. Production characteristics and body composition of juvenile cobia fed three different commercial diets in recirculating aquaculture systems

    Science.gov (United States)

    The effect of feeding three commercial diets on production characteristics and body composition of juvenile cobia Rachycentron canadum reared using recirculating aquaculture systems (RAS) was evaluated in a 56 d growth trial. Juvenile cobia (29.2 +/= 0.7 g, mean weight +/= SE) were stocked into thr...

  19. A Review of Factors Influencing Maturation of Atlantic Salmon Salmo salar with Focus on Water Recirculation Aquaculture System Environments

    Science.gov (United States)

    Maturation of Atlantic salmon Salmo salar is an extremely complex process, particularly in aquaculture systems, with many variables (known or otherwise) having the capacity to influence the timing and prevalence of maturation, and acting as promoters and/or inhibitors of sexual development. The vast...

  20. Single-sludge denitrification in recirculating aquaculture systems: effects of pre-fermentation and pH

    DEFF Research Database (Denmark)

    Suhr, Karin Isabel; Letelier-Gordo, Carlos Octavio; Prat Busquets, Pau

    2015-01-01

    Single-sludge denitrification (DN) reactors in aquaculture use the carbonous solid fish waste produced in the system to reduce the discharged nitrate load. The solid waste is available for denitrifiers when present in soluble, readily biodegradable form, and the transformation is accomplished...

  1. Preliminary studies on the depuration of common off-flavors from fish raised in recirculating aquaculture systems

    Science.gov (United States)

    “Off-flavor” problems can adversely impact the growth of the aquaculture industry. Fish raised in recirculating systems have the potential to develop the common off-flavors “earthy” and “musty” due to accumulation of the microbial metabolites geosmin and 2-methylisoborneol (MIB) in the fish flesh. ...

  2. Comparative performance of CO2 measuring methods: marine aquaculture recirculation system application

    Science.gov (United States)

    Pfeiffer, T.J.; Summerfelt, S.T.; Watten, B.J.

    2011-01-01

    Many methods are available for the measurement of dissolved carbon dioxide in an aqueous environment. Standard titration is the typical field method for measuring dissolved CO2 in aquaculture systems. However, titrimetric determination of dissolved CO2 in marine water aquaculture systems is unsuitable because of the high dissolved solids, silicates, and other dissolved minerals that interfere with the determination. Other methods used to measure dissolved carbon dioxide in an aquaculture water included use of a wetted CO2 probe analyzer, standard nomographic methods, and calculation by direct measurements of the water's pH, temperature, and alkalinity. The determination of dissolved CO2 in saltwater based on partial pressure measurements and non-dispersive infra-red (NDIR) techniques with a CO2 gas analyzer are widely employed for oceanic surveys of surface ocean CO2 flux and are similar to the techniques employed with the head space unit (HSU) in this study. Dissolved carbon dioxide (DC) determination with the HSU using a infra-red gas analyzer (IRGA) was compared with titrimetric, nomographic, calculated, and probe measurements of CO2 in freshwater and in saltwater with a salinity ranging from 5.0 to 30 ppt, and a CO2 range from 8 to 50 mg/L. Differences in CO2 measurements between duplicate HSUs (0.1–0.2 mg/L) were not statistically significant different. The coefficient of variation for the HSU readings averaged 1.85% which was better than the CO2 probe (4.09%) and that for the titrimetric method (5.84%). In all low, medium and high salinity level trials HSU precision was good, averaging 3.39%. Differences existed between comparison testing of the CO2 probe and HSU measurements with the CO2 probe readings, on average, providing DC estimates that were higher than HSU estimates. Differences between HSU and titration based estimates of DC increased with salinity and reached a maximum at 32.2 ppt. These differences were statistically significant (P < 0.05) at all

  3. Characterization of integrons and tetracycline resistance determinants in Aeromonas spp. isolated from South African aquaculture systems.

    Science.gov (United States)

    Jacobs, Liezl; Chenia, Hafizah Y

    2007-03-20

    An increasing incidence of multidrug resistance amongst Aeromonas spp. isolates, which are both fish pathogens and emerging opportunistic human pathogens, has been observed worldwide. This can be attributed to the horizontal transfer of mobile genetic elements, viz.: plasmids and class 1 integrons. The antimicrobial susceptibilities of 37 Aeromonas spp. isolates, from tilapia, trout and koi aquaculture systems, were determined by disc-diffusion testing. The plasmid content of each isolate was examined using the alkaline lysis protocol. Tet determinant type was determined by amplification using two degenerate primer sets and subsequent HaeIII restriction. The presence of integrons was determined by PCR amplification of three integrase genes, as well as gene cassettes, and the qacEDelta1-sulI region. Thirty-seven Aeromonas spp. isolates were differentiated into six species by aroA PCR-RFLP, i.e., A. veronii biovar sobria, A. hydrophila, A. encheleia, A. ichtiosoma, A. salmonicida, and A. media. High levels of resistance to tetracycline (78.3%), amoxicillin (89.2%), and augmentin (86.5%) were observed. Decreased susceptibility to erythromycin was observed for 67.6% of isolates. Although 45.9% of isolates displayed nalidixic acid resistance, majority of isolates were susceptible to the fluoroquinolones. The MAR index ranged from 0.12 to 0.59, with majority of isolates indicating high-risk contamination originating from humans or animals where antibiotics are often used. Plasmids were detected in 21 isolates, with 14 of the isolates displaying multiple plasmid profiles. Single and multiple class A family Tet determinants were observed in 27% and 48.7% of isolates, respectively, with Tet A being the most prevalent Tet determinant type. Class 1 integron and related structures were amplified and carried different combinations of the antibiotic resistance gene cassettes ant(3'')Ia, aac(6')Ia, dhfr1, oxa2a and/or pse1. Class 2 integrons were also amplified, but the

  4. Holographic Aquaculture

    Science.gov (United States)

    Ian, Richard; King, Elisabeth

    1988-01-01

    Proposed is an exploratory study to verify the feasibility of an inexpensive micro-climate control system for both marine and freshwater pond and tank aquaculture, offering good control over water temperature, incident light flux, and bandwidth, combined with good energy efficiency. The proposed control system utilizes some familiar components of passive solar design, together with a new holographic glazing system which is currently being developed by, and proprietary to Advanced Environmental Research Group (AERG). The use of solar algae ponds and tanks to warm and purify water for fish and attached macroscopic marine algae culture is an ancient and effective technique, but limited seasonally and geographically by the availability of sunlight. Holographic Diffracting Structures (HDSs) can be made which passively track, accept and/or reject sunlight from a wide range of altitude and azimuth angles, and redirect and distribute light energy as desired (either directly or indirectly over water surface in an enclosed, insulated structure), effectively increasing insolation values by accepting sunlight which would not otherwise enter the structure.

  5. Tracing dissolved organic matter (DOM) from land-based aquaculture systems in North Patagonian streams

    DEFF Research Database (Denmark)

    Nimptsch, Jorge; Woelfl, Stefan; Osorio, Sebastian;

    2015-01-01

    Chile is the second largest producer of salmonids worldwide. The first step in the production of salmonids takes place in land-based aquacultures. However, the effects of the discharge from these aquacultures on stream dissolved organic matter (DOM) content, molecular composition and degradabilit...

  6. Application and analytical verification of peracetic acid use in different types of freshwater aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    2011-01-01

    found to be in the order of a few minutes. The study revealed that PAA degrades so rapidly that insufficient disinfection is a likely outcome. The observations have applications for optimizing water treatment strategies with PAA. The investigations also indicated that the rapid degradation and hence......Peracetic acid (PAA) is a highly reactive peroxygen compound with wide-ranging antimicrobial effects. PAA has recently gained substantial attention, due to additional beneficial attributes such as easily degradability and harmless disinfection byproducts. However, PAA is only sporadically used...... of water sanitation with PAA application were used to analytically verify actual PAA concentration under real conditions at different kinds of aquaculture systems. A characteristic instant disinfection demand was found to be significantly positively related to water COD content, and PAA half-lives were...

  7. Broodstock management of the fine flounder Paralichthys adspersus (Steindachner, 1867) using recirculating aquaculture systems

    OpenAIRE

    Lili Carrera; Noemí Cota; Melissa Montes; Enrique Mateo; Verónica Sierralta; Teresa Castro; Angel Perea; Cristian Santos; Christian Catcoparco; Carlos Espinoza

    2013-01-01

    The present study describes the methodology used at IMARPE for the capture, acclimation and management of P. adspersus broodstock using recirculating aquaculture systems (RAS). RAS improved the water quality and maintained the environmental parameters during the acclimation period, temperature (17.2±1°C), oxygen (8.1±0.7 mg L-1), pH (7.3±0.2), ammonia (0.004±0.003 mg L-1), nitrite (0.52±0.2 mg L-1) and nitrate (3.45±2.6 mg L-1). Fish began to be fed normally from day 15 post-capture, once or ...

  8. Numerical simulation of the hydrodynamics within octagonal tanks in recirculating aquaculture systems

    Science.gov (United States)

    Liu, Yao; Liu, Baoliang; Lei, Jilin; Guan, Changtao; Huang, Bin

    2016-07-01

    A three-dimensional numerical model was established to simulate the hydrodynamics within an octagonal tank of a recirculating aquaculture system. The realizable k-ɛ turbulence model was applied to describe the flow, the discrete phase model (DPM) was applied to generate particle trajectories, and the governing equations are solved using the finite volume method. To validate this model, the numerical results were compared with data obtained from a full-scale physical model. The results show that: (1) the realizable k-ɛ model applied for turbulence modeling describes well the flow pattern in octagonal tanks, giving an average relative error of velocities between simulated and measured values of 18% from contour maps of velocity magnitudes; (2) the DPM was applied to obtain particle trajectories and to simulate the rate of particle removal from the tank. The average relative error of the removal rates between simulated and measured values was 11%. The DPM can be used to assess the self-cleaning capability of an octagonal tank; (3) a comprehensive account of the hydrodynamics within an octagonal tank can be assessed from simulations. The velocity distribution was uniform with an average velocity of 15 cm/s; the velocity reached 0.8 m/s near the inlet pipe, which can result in energy losses and cause wall abrasion; the velocity in tank corners was more than 15 cm/s, which suggests good water mixing, and there was no particle sedimentation. The percentage of particle removal for octagonal tanks was 90% with the exception of a little accumulation of ≤ 5 mm particle in the area between the inlet pipe and the wall. This study demonstrated a consistent numerical model of the hydrodynamics within octagonal tanks that can be further used in their design and optimization as well as promote the wide use of computational fluid dynamics in aquaculture engineering.

  9. BIOFILTERS IN AQUACULTURE

    Directory of Open Access Journals (Sweden)

    Ivo Šarić

    2010-07-01

    Full Text Available Recirculating aquaculture is one of the solutions to an environmentally sustainable and economically feasible aquaculture production, and can be established in either urban or rural communities. Controlled conditions enable optimal growth conditions suitable for the species in question during the whole growth process, as well as the shortening of the process itself, when compared to open uncontrolled systems. Recirculating systems are now one of the most researched fields of aquaculture, and biofiltration as the reduction of the poisonous ammonia compounds generated by digestion of proteins, is one of its most important parts. The aim of this study was to stress the importance of biofiltration, and to describe different designs of biofilters. Many biofilters are being used in commercial and research aquaculture facilities with differences in choice of working organism, design, material, price and etc. For the proper choice of biofilter it is necessary to know characteristics of each recirculating aquaculture system, because there are still no strict criteria for categorizing and applying different biofilter designs.

  10. Direct utilization of geothermal heat in cascade application to aquaculture and greenhouse systems at Navarro College. Annual report, January 1984-September 1984

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.

    1984-09-01

    Progress is reported on a project to use the 130/sup 0/F geothermal resource in central Texas. The system for cascading geothermal energy through aquaculture and greenhouse systems was completed and the first shrimp harvest was held. (MHR)

  11. Electron beam focusing system

    Energy Technology Data Exchange (ETDEWEB)

    Dikansky, N.; Nagaitsev, S.; Parkhomchuk, V.

    1997-09-01

    The high energy electron cooling requires a very cold electron beam. Thus, the electron beam focusing system is very important for the performance of electron cooling. A system with and without longitudinal magnetic field is presented for discussion. Interaction of electron beam with the vacuum chamber as well as with the background ions and stored antiprotons can cause the coherent electron beam instabilities. Focusing system requirements needed to suppress these instabilities are presented.

  12. Fate of water borne therapeutic agents and associated effects on nitrifying biofilters in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    Recent discharge restrictions on antibiotics and chemotherapeutant residuals used in aquaculture have several implications to the aquaculture industry. Better management practices have to be adopted, and documentation and further knowledge of the chemical fate is required for proper administration...... and to support the ongoing development of a sustainable aquaculture industry. A focal point of this thesis concerns formaldehyde (FA), a commonly used chemical additive with versatile aquaculture applications. FA is safe for use with fish and has a high treatment efficiency against fungal and parasite...... ≥2 mg/L. PAA and HP decay patterns were significantly affected by water quality parameters, i.e. at low organic matter content HP degradation was impeded due to microbial inhibition. FISH analysis on biofilm samples from two different types of RAS showed that Nitrosomonas oligotropha was the dominant...

  13. Nitrogen and Phosphorus Removal in the Recirculating Aquaculture System with Water Treatment Tank containing Baked Clay Beads and Chinese Cabbage

    OpenAIRE

    Aeknarin Thanakitpairin; Wiboonluk Pungrasmi; Sorawit Powtongsook

    2014-01-01

    This research aims to describe the nitrogen and phosphorus removal in Recirculating Aquaculture System (RAS) by crop plants biomass production. The 3 experiment systems consisted of 1 treatment (fish tank + baked clay beads + Chinese cabbage) and 2 controls as control-1 (fish tank only) and control-2 (fish tank + baked clay beads), were performed. With all experimental RAS, Nile tilapia (Oreochromis niloticus) was cultured at 2 kg/m3 density. The baked clay beads (8-16 mm in diameter) were fi...

  14. The influence of stocking density on the growth of common carp, Cyprinus carpio, in a recirculating aquaculture system

    OpenAIRE

    Ionica Enache; Victor Cristea; Tudor Ionescu; Săndita Ion

    2011-01-01

    The paper presents some aspects regarding the influence of stocking density on the breeding of the common carp in a recirculating aquaculture system (RAS). The experiment covered a 30 dayperiod. It was conducted in four aquaculture tanks, 500 L/tank, in the recirculating aquaculture pilot system of “Dunarea de Jos” University of Galați. Two kind of stocking density variants were compared: 64 kg/m3 in V1 (B1, B3) and 32 kg/m3 in V2 (B2, B4). The stocking density was: 491 fish in B1, avera...

  15. The potential use of constructed wetlands in a recirculating aquaculture system for shrimp culture.

    Science.gov (United States)

    Lin, Ying-Feng; Jing, Shuh-Ren; Lee, Der-Yuan

    2003-01-01

    A pilot-scale constructed wetland unit, consisting of free water surface (FWS) and subsurface flow (SF) constructed wetlands arranged in series, was integrated into an outdoor recirculating aquaculture system (RAS) for culturing Pacific white shrimp (Litopenaeus vannamei). This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of improvement in water quality of the culture tank on the growth and survival of shrimp postlarvae. During an 80-day culture period, the wetland unit operated at a mean hydraulic loading rate of 0.3 m/day and effectively reduced the influent concentrations of 5-day biochemical oxygen demand (BOD5, 24%), suspended solids (SS, 71%), chlorophyll a (chl-a, 88%), total ammonium (TAN, 57%), nitrite nitrogen (NO2-N, 90%) and nitrate nitrogen (NO3-N, 68%). Phosphate (PO4-P) reduction was the least efficient (5.4%). The concentrations of SS, Chl-a, turbidity and NO3-N in the culture tank water in RAS were significantly (Paquaculture system (CAS) that simulated static pond culture without wetland treatment. However, no significant difference (Psystems. At the end of the study, the harvest results showed that shrimp weight and survival rate in the RAS (3.8 +/-1.8 g/shrimp and 90%) significantly (Precirculating system. PMID:12663210

  16. Improving methane production and phosphorus release in anaerobic digestion of particulate saline sludge from a brackish aquaculture recirculation system.

    Science.gov (United States)

    Zhang, Xuedong; Ferreira, Rui B; Hu, Jianmei; Spanjers, Henri; van Lier, Jules B

    2014-06-01

    In this study, batch tests were conducted to examine the effects of trehalose and glycine betaine as well as potassium on the specific methanogenic activity (SMA), acid and alkaline phosphatase activity of anaerobic biomass and phosphorus release in anaerobic digestion of saline sludge from a brackish recirculation aquaculture system. The results of ANOVA and Tukey's HSD (honestly significant difference) tests showed that glycine betaine and trehalose enhanced SMA of anaerobic biomass and reactive phosphorus release from the particulate waste. Moreover, SMA tests revealed that methanogenic sludge, which was long-term acclimatized to a salinity level of 17 g/L was severely affected by the increase in salinity to values exceeding 35 g/L. Addition of compatible solutes, such as glycine betaine and trehalose, could be used to enhance the specific methane production rate and phosphorus release in anaerobic digestion from particulate organic waste produced in marine or brackish aquaculture recirculation systems.

  17. Quantitative role of shrimp fecal bacteria in organic matter fluxes in a recirculating shrimp aquaculture system.

    Science.gov (United States)

    Beardsley, Christine; Moss, Shaun; Malfatti, Francesca; Azam, Farooq

    2011-07-01

    Microorganisms play integral roles in the cycling of carbon (C) and nitrogen (N) in recirculating aquaculture systems (RAS) for fish and shellfish production. We quantified the pathways of shrimp fecal bacterial activities and their role in C- and N-flux partitioning relevant to culturing Pacific white shrimp, Penaeus (Litopenaeus) vannamei, in RAS. Freshly produced feces from P. vannamei contained 0.6-7 × 10(10) bacteria g(-1) dry wt belonging to Bacteroidetes (7%), Alphaproteobacteria (4%), and, within the Gammaproteobacteria, almost exclusively to the genus Vibrio (61%). Because of partial disintegration of the feces (up to 27% within 12 h), the experimental seawater became inoculated with fecal bacteria. Bacteria grew rapidly in the feces and in the seawater, and exhibited high levels of aminopeptidase, chitinase, chitobiase, alkaline phosphatase, α- and β-glucosidase, and lipase activities. Moreover, fecal bacteria enriched the protein content of the feces within 12 h, potentially enriching the feces for the coprophagous shrimp. The bacterial turnover time was much faster in feces (1-10 h) than in mature RAS water (350 h). Thus, shrimp fecal bacteria not only inoculate RAS water but also contribute to bacterial abundance and productivity, and regulate system processes important for shrimp health. PMID:21426366

  18. Integrated Multi-Trophic Recirculating Aquaculture System for Nile Tilapia (Oreochlomis niloticus

    Directory of Open Access Journals (Sweden)

    Puchong Sri-uam

    2016-06-01

    Full Text Available Three densities of the sex-reversed male Nile tilapia, Oreochromis niloticus (20, 25, 50 fish/m3 were cultivated in an integrated multi-trophic recirculating aquaculture system (IMRAS that involves the ecological relationship between several living organisms, i.e., phytoplankton, zooplankton, and aquatic plants. The results indicated that, by providing proper interdependency between various species of living organisms, the concentrations of ammonia, nitrite, nitrate, and phosphate in the system were maintained below dangerous levels for Nile tilapia throughout the cultivation period. The highest wet weight productivity of Nile tilapia of 11 ± 1 kg was achieved at a fish density of 50 fish/m3. The aquatic plants in the treatment tank could effectively uptake the unwanted nitrogen (N and phosphorus (P compounds with the highest removal efficiencies of 9.52% and 11.4%, respectively. The uptake rates of nitrogen and phosphorus by aquatic plants could be ranked from high to low as: Egeria densa > Ceratophyllum demersum > Vallisneria spiralis and Vallisneria americana > Hygrophila difformis. The remaining N was further degraded through nitrification process, whereas the remaining P could well precipitate in the soil sediment in the treatment tank.

  19. Inorganic nitrogen control in a novel zero-water exchanged aquaculture system integrated with airlift-submerged fibrous nitrifying biofilters.

    Science.gov (United States)

    Sesuk, Thanathon; Powtongsook, Sorawit; Nootong, Kasidit

    2009-03-01

    This work examined the feasibility of applying shrimp diets to establish nitrification on submerged fibrous biofilters. It also investigated the performance of a proposed zero-water exchanged aquaculture system, which integrated growing of aquatic stocks and operation of acclimated biofilters in the same environment. Addition of shrimp diets fully established nitrification within 3 weeks as indicated by continuous increase of nitrate and trivial levels of ammonium and nitrite. A series of batch experiment revealed an average ammonium degradation rate of 24.1mg Nm(-2) day(-1). Zero-water discharged tilapia cultivation could be carried out in the proposed aquaculture system for at least 44 days when daily inorganic loadings increased from 1.24 to 10.78mg Nl(-1) day(-1). The corresponding daily growth rates of tilapia from the proposed aquaculture systems integrated with acclimated biofilters varied from 3.01 to 3.35g day(-1), which was approximately 7-16% better than numbers from the systems using non-acclimated biofilters.

  20. Potential and limitations of ozone in marine recirculating aquaculture systems - Guidelines and thresholds for a safe application

    OpenAIRE

    Schröder, Jan

    2011-01-01

    The aim of the present thesis was to assess the potential and limitations of ozonation in marine recirculating aquaculture systems (RAS) while particularly focussing on the toxicity, formation and removal of ozone-produced oxidants (OPO) in order to develop guidelines and thresholds for a reasonable and safe ozone application. In the first two chapters the toxicity of OPO was investigated for Pacific white shrimp (Litopenaeus vannamei) and turbot (Psetta maxima) and maximum safe exposure leve...

  1. The Effects of Some Phytobiotics on Biochemical Composition of Oreochromis Niloticus Meat Reared in a Recirculating Aquaculture System

    OpenAIRE

    Alina Antache; Cristea Victor; Grecu Iulia; Dediu Lorena; Mocanu (Cretu) Mirela; Ion (Placinta) Sandita; Petrea Stefan Mihai

    2013-01-01

    The purpose of this experiment is the evaluation of biochemical composition of Nile tilapia meat by administrating  several phytobiotics in feed. Oreochromis niloticus, with an initial average weight of 125.41±34.33 g/exemplar, were reared, during six weeks in a recirculating aquaculture system. The phytobiotics from this experiment were administered in feed in a concentration of 1%/kg feed and consist in: thyme (Thymus vulgaris), fenugreek (Trigonela foenum graecum), neem (Azadirachta indica...

  2. Observations on side-swimming rainbow trout in water recirculation aquaculture systems.

    Science.gov (United States)

    Good, Christopher; Davidson, John; Kinman, Christin; Kenney, P Brett; Bæverfjord, Grete; Summerfelt, Steven

    2014-12-01

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRASs), it was observed that Rainbow Trout Oncorhynchus mykiss in all WRASs exhibited a higher-than-normal prevalence of side swimming (i.e., controlled, forward swimming but with misaligned orientation such that the fish's sagittal axis is approximately parallel to the horizontal plane). To further our understanding of this abnormality, a substudy was conducted wherein side swimmers and normally swimming fish were selectively sampled from each WRAS and growth performance (length, weight), processing attributes (fillet yield, visceral index, ventrum [i.e., thickness of the ventral "belly flap"] index), blood gas and chemistry parameters, and swim bladder morphology and positioning were compared. Side swimmers were found to be significantly smaller in length and weight and had less fillet yield but higher ventrum indices. Whole-blood analyses demonstrated that, among other things, side swimmers had significantly lower whole-blood pH and higher Pco2. Side swimmers typically exhibited swim bladder malformations, although the positive predictive value of this subjective assessment was only 73%. Overall, this study found several anatomical and physiological differences between side-swimming and normally swimming Rainbow Trout. Given the reduced weight and fillet yield of market-age side swimmers, producers would benefit from additional research to reduce side-swimming prevalence in their fish stocks.

  3. Performance evaluation of the compact aquaculture system integrating submerged fibrousnitrifying biofilters

    Directory of Open Access Journals (Sweden)

    Sorawit Powtongsook

    2012-02-01

    Full Text Available This experiment assessed the performance of submerged fibrous nitrifying biofilters (SFNBs to carry out the zerowaterexchange tilapia cultivation. Without biofilter cleaning, the SFNBs (21 m of biofilter length were susceptible tohydrogen sulfide production when operating beyond the aquaculture density of 13.62 kg/m3. The SFNBs were able tomaintain total ammonia nitrogen (TAN and nitrite below 1.0 mg N/L throughout the experiment and could handle inorganicnitrogen loading as high as 38.6 mg N/L/day when the solid removal from biofilters was performed biweekly. Ammoniumdegradation rate measured at the end of this study was 380±66 mg N/m2/day for biofilters subjected to cleaning. A significantlylower rate of 41.4±2.86 mg N/m2/day was associated with biofilters without any solid removal. Finally, the SFNBsshould be attractive for budget-limited farmers since they are simple to build and operate and can provide alternatives tocage-cultured systems.

  4. Membrane filtration coupled with chemical precipitation to treat recirculating aquaculture system effluents.

    Science.gov (United States)

    Yang, Ling; Zhou, Hongde; Moccia, Richard

    2006-01-01

    Effluents from recirculating aquaculture systems (RAS) contain high concentrations of nitrogen and phosphorous wastes and thus often require proper treatment to prevent potential detrimental impacts on receiving water bodies. The purpose of this study was to evaluate the feasibility of membrane filtration coupled with chemical precipitation as a pretreatment step with emphasis on phosphorus removal from RAS effluents. Chemical precipitation tests were conducted by adding magnesium chloride and alum at different chemical concentrations and pH values, respectively. Crossflow, flat-sheet membrane filtration modules were used to examine the effects of transmembrane pressure and crossflow velocity in terms of solid/liquid separation efficiency and permeate flux decline. The results showed that membrane filtration can effectively separate the phosphorus precipitates after chemical precipitation. The total phosphorus in the treated effluent was reduced to less than 0.05 mg L(-1) with a removal efficiency of more than 90%. However, much lower removal efficiencies were obtained for total organic carbon (TOC), total nitrogen, and turbidity. It was concluded that membrane filtration coupled with chemical precipitation can become an effective, compact treatment technology to meet the stringent regulatory requirements for RAS effluent discharge. PMID:17071913

  5. Conditioning of broodstock of tiger grouper, Epinephelus fuscoguttatus, in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Saleem Mustafa

    2015-11-01

    Full Text Available Closing the cycle of commercial species of fish in a recirculating aquaculture system is gaining importance for a number of practical advantages. Founder broodstock originating from the wild population is conditioned to live in hatchery tanks under suitable environmental and feeding conditions and is induced to breed. The juveniles are grown to maturity and facilitated to spawn in captivity to close the life cycle in the hatchery. This experiment was carried out on tiger grouper (Epinephelus fuscoguttatus. After preliminary observations, it was possible to identify appropriate environmental conditions in terms of water quality parameters, volume of broodstock tanks and ration. Growth was nearly isometric (growth exponent = 2.9185 and the condition factor = 1.86. This reflected good management conditions. Cues that trigger sex reversal in this protogynous fish in the hatchery were different from those that operate in nature. It appears that the differentiation of some individuals of a cohort into male sex is linked to socio-demographic cues as well as internal condition of the fish because it related to age and physiological condition. This view was reinforced by a lack of response in young fish to similar cues. The information generated through this study defines what is required for optimum conditioning of tiger grouper broodstock and explains the cues involved in sex differentiation.

  6. [Nitrate removal from recirculating aquaculture system using polyhydroxybutyrate-co-hydroxyvalerate as carbon source ].

    Science.gov (United States)

    Zhang, Lanhe; Liu, Lili; Qiu, Tianlei; Gao, Min; Han, Meilin; Yuan, Ding; Wang, Xuming

    2014-09-01

    [ OBJECTIVE] Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) was used as solid carbon source and biofilm carrier to remove nitrate from recirculating aquaculture system (RAS). Dynamics of microbial community structure in biofilm coating on carbon source packed into denitrification reactor were investigated. [METHODS] Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the microbial community in biofilm from denitrifiation reactor. Bacteria degrading PHBV were isolated from the reactor using pure culture method. [RESULTS] Nitrate decreased remarkably in the RAS connected with dentrification reactor. In contrast, Nitrate increased continuously in the conventional RAS without dentrification reactor. According to the phylogenetic analysis, the microbes in the biofilm samples from denitrification reactor were divided into Proteobacteria ( p-proteobacteria, γ-proteobacteria and δ- proteobacteria) , Firmicutes and Bacteroidetes. The major advantageous populations were Acidovorax and Bacillus in the 40-day reactor. The advantageous populations in the 150-day reactor were in order of Clostridium, Desulfitobacterium, Dechloromonas, Pseudoxanthomonas and Flavobacterium. Pure cultures of bacteria degrading PHBV isolated from denitrification reactor were classified into Acidovorax, Methylibium, Pseudoxanthomonas and Dechloromonas. [CONCLUSION] Nitrate could be removed effectively from RAS using PHBV as carbon source. Advantageous bacteria and their dynamic changes were ascertained in biofilm from denitrification reactor packed with PHBV. PMID:25522594

  7. Mathematical modelling of nutrient balance of a goldfish (Carassius auratus Linn. recirculating aquaculture system (GRAS

    Directory of Open Access Journals (Sweden)

    Sudeep Puthravilakom Sadasivan Nair

    2010-08-01

    Full Text Available In the present study, a goldfish (Carassius auratus Linn. recirculating aquaculture system (GRAS has been developed. The GRAS consisted of a culture tank, a screen filter and a foam fractionator for removal of particulate and dissolved solids and a trickling filter for conversion of ammonium- and nitrite-nitrogen to relatively harmless nitrate-nitrogen. The culture of goldfish at a stocking density of 1.08 kg/m3 was continued for a period of two and half months. Based on mass balance analysis of ammonium- and nitrate-nitrogen and assuming the trickling filter to be a plug flow reactor, a model was formulated to determine the necessary recirculation flow rate at different times of culture for maintaining the major nutrients, viz., ammonium- and nitrate-nitrogen below their permissible limits. The model was calibrated and validated using the real time data obtained from the experimental run. The high values of coefficient of determination and low values of root mean square error show the effectiveness of the model.

  8. Broodstock management of the fine flounder Paralichthys adspersus (Steindachner, 1867 using recirculating aquaculture systems

    Directory of Open Access Journals (Sweden)

    Lili Carrera

    2013-03-01

    Full Text Available The present study describes the methodology used at IMARPE for the capture, acclimation and management of P. adspersus broodstock using recirculating aquaculture systems (RAS. RAS improved the water quality and maintained the environmental parameters during the acclimation period, temperature (17.2±1°C, oxygen (8.1±0.7 mg L-1, pH (7.3±0.2, ammonia (0.004±0.003 mg L-1, nitrite (0.52±0.2 mg L-1 and nitrate (3.45±2.6 mg L-1. Fish began to be fed normally from day 15 post-capture, once or twice a day using live fish (Odonthestes regia regia, Mugil cephalus, crustacean (Emerita analoga, fresh food (Engraulis ringens and Dosidicus gigas and artificial feed. A significant loss in the weight of the fish was registered during the first days of captivity, followed by a continuous increase in both sexes. The specific growth rate was positive from the third month of captivity, being the relative growth rate 24.5% and 16.2% in August 2010 in males and females, respectively. Different internal and external parasites were detected in the fish, being Entobdella sp. and Philometra sp. the prevailing parasites observed during samplings.

  9. Biomethanation and microbial community changes in a digester treating sludge from a brackish aquaculture recirculation system.

    Science.gov (United States)

    Zhang, Xuedong; Tao, Yu; Hu, Jianmei; Liu, Gang; Spanjers, Henri; van Lier, Jules B

    2016-08-01

    Using a high-salinity-adapted inoculum and a moderate stepwise-increased organic loading rate (OLR), a stable digester performance was achieved in treating sludge from a brackish aquaculture recirculation system. The specific methane yield was distinctly enhanced, reaching 0.203LCH4/gCODadded, compared to literature values (0.140-0.154LCH4/gCODadded) from the salty sludges. OLR adjustment and the fecal substrate substantially influenced population changes in the digester. Within the bacterial subpopulations, the relative abundance of Bacillus and Bacteroides declined, accompanied by the increase of Clostridium and Trigonala over time. The results show Trigonala was derived from the substrate and accumulated inside the digester. The most abundant methanogen was Methanosarcina in the inoculum and the digestates. The Methanosarcina proliferation can be ascribed to its metabolic versatility, probably a feature of crucial importance for high-salinity environments. Other frequently observed methanogens were outcompeted. The population similarity at the genus level between inoculum and digestates declined during the initial stage and afterwards increased. PMID:27155261

  10. An optimized and simplified method for analysing urea and ammonia in freshwater aquaculture systems

    DEFF Research Database (Denmark)

    Larsen, Bodil Katrine; Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg

    2015-01-01

    This study presents a simple urease method for analysis of ammonia and urea in freshwater aquaculture systems. Urea is hydrolysed into ammonia using urease followed by analysis of released ammonia using the salicylate-hypochlorite method. The hydrolysis of urea is performed at room temperature...... and without addition of a buffer. A number of tests were performed on water samples obtained from a commercial rainbow trout farm to determine the optimal urease concentration and time for complete hydrolysis. One mL of water sample was spiked with 1.3 mL urea at three different concentrations: 50 lg L 1, 100...... lg L 1 and 200 lg L 1 urea-N. In addition, five concentrations of urease were tested, ranging from 0.1 U mL 1 to 4 U mL 1. Samples were hydrolysed for various time periods ranging from 5 to 120 min. A urease concentration of 0.4 U mL 1 and a hydrolysis period of 120 min gave the best results, with 99...

  11. Aquaculture Information Package

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, T.; Rafferty, K. [editors

    1998-01-01

    This package of information is intended to provide background to developers of geothermal aquaculture projects. The material is divided into eight sections and includes information on market and price information for typical species, aquaculture water quality issues, typical species culture information, pond heat loss calculations, an aquaculture glossary, regional and university aquaculture offices and state aquaculture permit requirements.

  12. An integrated closed system for fish-plankton aquaculture in Amazonian fresh water.

    Science.gov (United States)

    Gilles, S; Ismiño, R; Sánchez, H; David, F; Núñez, J; Dugué, R; Darias, M J; Römer, U

    2014-08-01

    A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplanktivorous fishes (Loricariidae and Cichlidae), maintained without external feeding in the sewage volume, mineralized organic matter and permitted the stabilization of the phytoplankton biomass. Water exchange and organic waste discharge were not necessary. In this paper we describe the processes undertaken to equilibrate this ecosystem: first the elimination of an un-adapted spiny alga, Golenkinia sp., whose proliferation was favored by the presence of a small rotifer, Trichocerca sp., and second the control of this rotifer proliferation via the introduction of two cichlid species, Acaronia nassa Heckel, 1840 and Satanoperca jurupari Heckel, 1840, in the sewage part. This favored some development of the green algae Nannochloris sp. and Chlorella sp. At that time we took the opportunity to begin a 3-month rearing test of P. punctifer. The mean specific growth rate and feed conversion ratio (FCR) of P. punctifer were 1.43 and 1.27, respectively, and the global FCR, including fish in the sewage part, was 1.08. This system has proven to be suitable for growing P. punctifer juveniles out to adult, and provides several practical advantages compared with traditional recirculating clear water systems, which use a combination of mechanical and biological filters and require periodic waste removal, leading to water and organic matter losses. PMID:24849417

  13. Importance of prebiotics in aquaculture as immunostimulants. Effects on immune system of Sparus aurata and Dicentrarchus labrax.

    Science.gov (United States)

    Carbone, Donatella; Faggio, Caterina

    2016-07-01

    Infectious diseases in fish represent a major problem for the aquaculture field as they produce extensive damages and loss. Over the last few years, with increased development of the aquaculture industry, different methods have been used to contrast these pathologies. Common interest has led to the use of components (as additives in diets) that could contrast diseases without causing any negative impact on the environment. These components are represented by prebiotics, probiotics, and plant extracts. In this review, the effects of prebiotics are described. Prebiotics are indigestible fibres fermented by gut enzymes and commensal bacteria, whose beneficial effects are due to the by-products generated from fermentation. The influence of pre-biotics on the immune system of fish is called immunosaccharides. Mannanoligosaccharides (MOS), Fructooligosaccharides (FOS) and Inulin act at different levels in the innate immune response. For example, through phagocytosis, lysozyme activity, and the complement system activity, an increase in fish growth and an amelioration of their health status is brought about. In this review, the use of prebiotics in aquaculture, such as immunostimulants, has been highlighted: particularly in two teleost fish species, Sparus aurata and Dicentrarchus labrax. The results demonstrate that the road is still long and further studies are required, but the use of prebiotics, individually or coupled together, can open the doors to pioneering a new model of alternative components to antimicrobial agents. PMID:27074444

  14. Improved water quality in recirculating aquaculture systems (RAS) by applying a membrane bioreactor (MBR) concept for removal of colloidal and fine suspended solids

    OpenAIRE

    Holan, Astrid Buran

    2013-01-01

    The world’s human population is growing, and there is an increased demand for food. Aquaculture production is increasing rapidly to meet these demands and there is a growing interest for recirculating aquaculture systems (RAS) to maximize production. A typical RAS facility consists of production tanks and a water treatment compartment for removal or conversion of accumulated nutrients, organic matter and particulates where the treated water is recycled to the production tanks. Reuse of water ...

  15. Errors in experimental design and statistical analysis of aquaculture diet evaluation studies induced by filtration systems

    Directory of Open Access Journals (Sweden)

    Michael F. Tlusty

    2010-07-01

    Full Text Available While single factor diet studies appear to be of simple design, the space constraints in aquaculture caused by the need to filter the aqueous media often c reate constraints on the implementation of the experimental design. A number of papers have been published in which the experimental design and subsequent analysis is incorrect. This paper reviews the principles of experimental design as it related to single factor diet evaluation studies in aquaculture. By adhering tosimple design principles to ensure that experimental units are independent, the data generated by future experiments will be of high quality and results more robust.

  16. Identification of Bacterial Community Composition in Freshwater Aquaculture System Farming of Litopenaeus vannamei Reveals Distinct Temperature-Driven Patterns

    Directory of Open Access Journals (Sweden)

    Yuyi Tang

    2014-08-01

    Full Text Available Change in temperature is often a major environmental factor in triggering waterborne disease outbreaks. Previous research has revealed temporal and spatial patterns of bacterial population in several aquatic ecosystems. To date, very little information is available on aquaculture environment. Here, we assessed environmental temperature effects on bacterial community composition in freshwater aquaculture system farming of Litopenaeus vannamei (FASFL. Water samples were collected over a one-year period, and aquatic bacteria were characterized by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE and 16S rDNA pyrosequencing. Resulting DGGE fingerprints revealed a specific and dynamic bacterial population structure with considerable variation over the seasonal change, suggesting that environmental temperature was a key driver of bacterial population in the FASFL. Pyrosequencing data further demonstrated substantial difference in bacterial community composition between the water at higher (WHT and at lower (WLT temperatures in the FASFL. Actinobacteria, Proteobacteria and Bacteroidetes were the highest abundant phyla in the FASFL, however, a large number of unclassified bacteria contributed the most to the observed variation in phylogenetic diversity. The WHT harbored remarkably higher diversity and richness in bacterial composition at genus and species levels when compared to the WLT. Some potential pathogenenic species were identified in both WHT and WLT, providing data in support of aquatic animal health management in the aquaculture industry.

  17. Performance of Nile tilapia Oreochromis niloticus fingerlings in a hyper-intensive recirculating aquaculture system with low water exchange

    OpenAIRE

    M Gullian-Klanian; C Arámburu-Adame

    2013-01-01

    The aim of this paper was evaluate the performance of Nile tilapia fingerlings (Oreochromis niloticus) raised at hyper intensive stocking density in a recirculating aquaculture system (RAS) with minimum water replacing. The experimental system was performed in a single-batch nursery system to obtain 50 g fish size in 60 days. Fish (2.07 ± 0.04 g) were stocked in triplicate at 400 (T1), 500 (T2) and 600 (T3) fish m-3 (0.84, 1.05, 1.22 kg m-3). RAS functioned with 12,000 L of recirculating wate...

  18. Nutrient Discharge from aquaculture operations in function of system design and production enviorment

    NARCIS (Netherlands)

    Verdegem, M.C.J.

    2013-01-01

    In aquaculture, nutrient loading is defined as the difference between nutrients supplied with fertilizers and feed and nutrients harvested in the form of finfish, crustaceans, molluscs and seaweeds. On average, the production of finfish and crustaceans results in a net nutrient loading, while for th

  19. Overview of sustainable marine aquaculture systems engineering projects with emphasis on biofiltration

    Science.gov (United States)

    The rate of ammonia removal for moving bed and static bed biofilters with plastic media was determined for various feed loading rates, flow rates, and salinity. Ammonia removal rates in the eight propeller-wash floating plastic bead filters (0.71 m3) utilized in the 45 m3 recirculating aquaculture ...

  20. Inland marine fish culture in low-salinity recirculating aquaculture systems

    Science.gov (United States)

    Expansion of marine aquaculture is challenged by the high cost and limited availability of coastal land and water resources, effluent concerns, high production costs, restricted growing seasons, lack of quality seedstock, and inadequate regulatory and permitting processes. Many of these constraints...

  1. Removal of nitrogen by Algal Turf Scrubber Technology in recirculating aquaculture system

    NARCIS (Netherlands)

    Valeta, J.; Verdegem, M.C.J.

    2015-01-01

    Ongoing research in recirculation aquaculture focuses on evaluating and improving the purification potential of different types of filters. Algal Turf Scrubber (ATS) are special as they combine sedimentation and biofiltration. An ATS was subjected to high nutrient loads of catfish effluent to examin

  2. Optimizing Hydraulic Retention Times in Denitrifying Woodchip Bioreactors Treating Recirculating Aquaculture System Wastewater.

    Science.gov (United States)

    Lepine, Christine; Christianson, Laura; Sharrer, Kata; Summerfelt, Steven

    2016-05-01

    The performance of wood-based denitrifying bioreactors to treat high-nitrate wastewaters from aquaculture systems has not previously been demonstrated. Four pilot-scale woodchip bioreactors (approximately 1:10 scale) were constructed and operated for 268 d to determine the optimal range of design hydraulic retention times (HRTs) for nitrate removal. The bioreactors were operated under HRTs ranging from 6.6 to 55 h with influent nitrate concentrations generally between 20 and 80 mg NO-N L. These combinations resulted in N removal rates >39 g N m d, which is greater than previously reported. These high removal rates were due in large part to the relatively high chemical oxygen demand and warm temperature (∼19°C) of the wastewater. An optimized design HRT may not be the same based on metrics of N removal rate versus N removal efficiency; longer HRTs demonstrated higher removal efficiencies, and shorter HRTs had higher removal rates. When nitrate influent concentrations were approximately 75 mg NO-N L ( = 6 sample events), the shortest HRT (12 h) had the lowest removal efficiency (45%) but a significantly greater removal rate than the two longest HRTs (42 and 55 h), which were N limited. Sulfate reduction was also observed under highly reduced conditions and was exacerbated under prolonged N-limited environments. Balancing the removal rate and removal efficiency for this water chemistry with a design HRT of approximately 24 h would result in a 65% removal efficiency and removal rates of at least 18 g N m d. PMID:27136146

  3. The influence of pellets quality on the growth of sterlet, in recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Corina Sion

    2011-04-01

    Full Text Available The paper presents some aspects regarding the influence of food quality on the breeding of sterlet, Acipenser ruthenus Linnaeus, 1758, in a recirculating aquaculture system (RAS. The experiment took place over 30 days, in four pilot breeding units type aquaria of 300 liters in volume. Two kind of variants were compared, with repetition, V1 with 46% crude protein and V2 with 30% crude protein, respectively. The stocking density was of 14 fish/unit. The same feeding level of 8 g/kg metabolic weight (1.5% from total biomass was used in every unit. The technological indicators that showed up at the end of the experiment revealed the following: the mean biomass gain in V1 was of 0.74 kg/m3 compared to 0.39 kg/m3in V2; this was nearly perfectly correlated with the food quality. The growth rate (GR variated from 6.70 to 8.13 g/day in V1 and 3.63-4.17 g/day in V2; the specific growth rate (SGR, calculated as a mean value of the two repetitions of each variant, was of 1.11 g%/day in V1 and 0.63 g%/day in V2; the feed conversion ratio (FCR, calculated as the mean value of the two repetitions from the two variants, was of 1.49 in V1 and of 2.81 in V2. The parameters of fish breeding showed that changing the quality of fodder, the fish growing was positively influenced. This experiment showed also that sterlet is a sturgeon with a moderate growth rate and it is possible to obtain an increase of fish biomass using pellets with 30-46 % crude protein.

  4. Trophic structure in a pilot system for the integrated multi-trophic aquaculture off the east coast of Korean peninsula as determined by stable isotopes

    International Nuclear Information System (INIS)

    Highlights: • A pilot system for the integrated multi-trophic aquaculture was installed. • The black rockfish, sea cucumber, oyster, and macroalgae were co-cultured. • Co-cultured sea cucumber at the IMTA site assimilated aquaculture wastes. • Fish cage-waste contribution to food web in/around the IMTA system was minor. • The sea cucumber was identified as an extractive species of fish cage wastes. - Abstract: To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ13C and δ15N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment

  5. Comparison of Atlantic salmon net pen and recirculating aquaculture systems: economical, technological and environmental issues

    OpenAIRE

    Dekhtyarev, Vitaly

    2014-01-01

    The modern aquaculture industry is a rapidly developing sector of the fisheries industry. Among the fish species reared in marine waters Atlantic salmon (Salmo salar) shares a significant part. Nowadays, the largest salmon producing countries are Norway, Chile and Scotland. The common technology used in the salmon production is a sea cage, which is presented in a form of floating plastic rings or robust metal installations fastened to a barge. In both cases, the fish is placed ...

  6. Single-sludge denitrification in recirculating aquaculture systems: Effects of pre-fermentation and pH

    DEFF Research Database (Denmark)

    Suhr, Karin Isabel; Letelier Gordo, Carlos Octavio; Prat Busquets, Pau

    2014-01-01

    Single-sludge denitrification (DN) reactors in aquaculture utilize the solid fish waste produced in the system to reduce the nitrate load discharged. The solid waste is available for denitrifiers when present in soluble readily biodegradable form. A transformation accomplished by bacterial...... hydrolysis (and fermentation). The objective of this study was to quantify the effect of pre-fermentation of the solid fish waste on single-sludge DN-reactor efficiency. Pre-fermentation times tested were; 0 (no pre-fermentation), 1 d, 5 d, and 10 d. The efficiency was quantified as the potential DN...

  7. Effectiveness of Floating Micro-Bead Bio-Filter for Ornamental Fish in a Re-Circulating Aquaculture System

    OpenAIRE

    R Fadhil

    2011-01-01

    Bio-filtration has been widely used in re-circulating aquaculture system to remove waste and to convert toxic ammonia andnitrite into safe end products ornamental fish and other aquatic organisms. However, the study of micro-bead usage as the filter medium has not yet been broadened and thoroughly developed. Therefore, the aim of this study is to construct a biological filter made from polyethylene micro-bead as the filter medium and to analyze its effectiveness in removingwaste as well as in...

  8. Effect of stocking density on performances of juvenile turbot ( Scophthalmus maximus) in recirculating aquaculture systems

    Science.gov (United States)

    Li, Xian; Liu, Ying; Blancheton, Jean-Paul

    2013-05-01

    Limited information has been available about the influence of loading density on the performances of Scophthalmus maximus, especially in recirculating aquaculture systems (RAS). In this study, turbot (13.84±2.74 g; average weight±SD) were reared at four different initial densities (low 0.66, medium 1.26, sub-high 2.56, high 4.00 kg/m2) for 10 weeks in RAS at 23±1°C. Final densities were 4.67, 7.25, 14.16, and 17.47 kg/m2, respectively, which translate to 82, 108, 214, and 282 percent coverage of the tank bottom. Density had both negative and independent impacts on growth. The final mean weight, specific growth rate (SGR), and voluntary feed intake significantly decreased and the coefficient of variation (CV) of final body weight increased with increase in stocking density. The medium and sub-high density groups did not differ significantly in SGR, mean weight, CV, food conversion rate (FCR), feed intake, blood parameters, and digestive enzymes. The protease activities of the digestive tract at pH 7, 8.5, 9, and 10 were significantly higher for the highest density group, but tended to be lower (not significantly) at pH 4 and 8.5 for the lowest density group. The intensity of protease activity was inversely related to feed intake at the different densities. Catalase activity was higher (but not significantly) at the highest density, perhaps because high density started to induce an oxidative effect in turbot. In conclusion, turbot can be cultured in RAS at a density of less than 17.47 kg/m2. With good water quality and no feed limitation, initial density between 1.26 and 2.56 kg/m2 (final: 7.25 and 14.16 kg/m2) would not negatively affect the turbot cultured in RAS. For culture at higher density, multi-level feeding devices are suggested to ease feeding competition.

  9. Effect of stocking density on performances of juvenile turbot (Scophthalmus maximus) in recirculating aquaculture systems

    Institute of Scientific and Technical Information of China (English)

    LI Xian; LIU Ying; Jean-Paul BLANCHETON

    2013-01-01

    Limited information has been available about the influence of loading density on the performances of Scophthalmus maximus,especially in recirculating aquaculture systems (RAS).In this study,turbot (13.84±2.74 g; average weight±SD) were reared at four different initial densities (low 0.66,medium 1.26,sub-high 2.56,high 4.00 kg/m2) for 10 weeks in RAS at 23±1℃.Final densities were 4.67,7.25,14.16,and 17.47 kg/m2,respectively,which translate to 82,108,214,and 282 percent coverage of the tank bottom.Density had both negative and independent impacts on growth.The final mean weight,specific growth rate (SGR),and voluntary feed intake significantly decreased and the coefficient of variation (CV) of final body weight increased with increase in stocking density.The medium and sub-high density groups did not differ significantly in SGR,mean weight,CV,food conversion rate (FCR),feed intake,blood parameters,and digestive enzymes.The protease activities of the digestive tract at pH 7,8.5,9,and 10 were significantly higher for the highest density group,but tended to be lower (not significantly) at pH 4 and 8.5for the lowest density group.The intensity of protease activity was inversely related to feed intake at the different densities.Catalase activity was higher (but not significantly) at the highest density,perhaps because high density started to induce an oxidative effect in turbot.In conclusion,turbot can be cultured in RAS at a density of less than 17.47 kg/m2.With good water quality and no feed limitation,initial density between 1.26 and 2.56 kg/m2 (final:7.25 and 14.16 kg/m2) would not negatively affect the turbot cultured in RAS.For culture at higher density,multi-level feeding devices are suggested to ease feeding competition.

  10. [Treatment of marine-aquaculture effluent by the multi-soil-layer (MSL) system and subsurface flow constructed wetland].

    Science.gov (United States)

    Song, Ying; Huang, Yu-ting; Ge, Chuan; Zhang, Hao; Chen, Xin; Zhang, Zhi-jianz; Luo, An-cheng

    2014-09-01

    To evaluate the feasibility of using multi-soil-layer (MSL) system and subsurface flow constructed wetland to treat the wastewater of marine cultured Penaeus vannamei and to determine the suitable process for the local aquaculture wastewater pollution characteristics. In this study, MSL system and four constructed wetland systems with Spartina anglica, Phragmites australis, Typha latifolia and unplanted system were evaluated for their potentials of pollutants removal capacity. The results showed the average removal rates of chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), ammonia nitrogen (NH(4)+ -N) and nitrate (NO-(3) -N) by MSL system were 80. 38% ± 2. 14% , 68. 14% ± 3.51% , 40.79% ± 3. 10% , 42. 68% ± 2.90% and 54. 19% ± 5. 15% , respectively. Additionally, the ability of pollutants removal of other four wetland systems decreased in the order: Spartina anglica, Phragmites australis, Typha latifolia and unplanted system. PMID:25518662

  11. Aquaculture information package

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, T.; Rafferty, K.

    1998-08-01

    This package of information is intended to provide background information to developers of geothermal aquaculture projects. The material is divided into eight sections and includes information on market and price information for typical species, aquaculture water quality issues, typical species culture information, pond heat loss calculations, an aquaculture glossary, regional and university aquaculture offices and state aquaculture permit requirements. A bibliography containing 68 references is also included.

  12. Anaerobic ammonium-oxidizing (anammox) bacteria and associated activity in fixed-film biofilters of a marine recirculating aquaculture system.

    Science.gov (United States)

    Tal, Yossi; Watts, Joy E M; Schreier, Harold J

    2006-04-01

    Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR products by denaturing gradient gel electrophoresis and sequencing of the different phylotypes revealed a diverse biofilter microbial community. While Planctomycetales were found in all three communities, the anaerobic denitrifying biofilters contained one clone that exhibited high levels of sequence similarity to known anammox bacteria. Fluorescence in situ hybridization studies using an anammox-specific probe confirmed the presence of anammox Planctomycetales in the microbial biofilm from the denitrifying biofilters, and anammox activity was observed in these biofilters, as detected by the ability to simultaneously consume ammonia and nitrite. To our knowledge, this is the first identification of anammox-related sequences in a marine recirculating aquaculture filtration system, and our findings provide a foundation for incorporating this important pathway for complete nitrogen removal in such systems.

  13. Anaerobic ammonium-oxidizing (anammox) bacteria and associated activity in fixed-film biofilters of a marine recirculating aquaculture system.

    Science.gov (United States)

    Tal, Yossi; Watts, Joy E M; Schreier, Harold J

    2006-04-01

    Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR products by denaturing gradient gel electrophoresis and sequencing of the different phylotypes revealed a diverse biofilter microbial community. While Planctomycetales were found in all three communities, the anaerobic denitrifying biofilters contained one clone that exhibited high levels of sequence similarity to known anammox bacteria. Fluorescence in situ hybridization studies using an anammox-specific probe confirmed the presence of anammox Planctomycetales in the microbial biofilm from the denitrifying biofilters, and anammox activity was observed in these biofilters, as detected by the ability to simultaneously consume ammonia and nitrite. To our knowledge, this is the first identification of anammox-related sequences in a marine recirculating aquaculture filtration system, and our findings provide a foundation for incorporating this important pathway for complete nitrogen removal in such systems. PMID:16597996

  14. Osnovy formirovanija sistemy upravlenija riskami proektov innovacionnogo razvitija akvakul'tury v regione (Na primere Kaliningradskoj oblasti) [The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study

    OpenAIRE

    Serbulov Alexey; Stepanov Alexey; Polyakov Oleg

    2012-01-01

    This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kali...

  15. Impact of depuration of earth-musty off-flavors on fillet quality of atlantic salmon, Salmo salar, cultured in a recirculating aquaculture system

    Science.gov (United States)

    Over the past decade in the United States, there has been increased interest in the establishment and use of land-based, closed-containment systems [e.g., recirculating aquaculture system (RAS)] for salmonid culture. These culture systems have unique challenges compared to net pen culture of salmon...

  16. Animal protein production modules in biological life support systems: Novel combined aquaculture techniques based on the closed equilibrated biological aquatic system (C.E.B.A.S.)

    Science.gov (United States)

    Blüm, V.; Andriske, M.; Kreuzberg, K.; Schreibman, M. P.

    Based on the experiences made with the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) which was primarily deveoloped for long-term and multi-generation experiments with aquatic animals and plants in a space station highly effective fresh water recycling modules were elaborated utilizing a combination of ammonia oxidizing bacteria filters and higher plants. These exhibit a high effectivity to eliminate phosphate and anorganic nitrogen compounds and arc. in addidition. able to contribute to the oxygen supply of the aquatic animals. The C.E.B.A.S. filter system is able to keep a closed artificial aquatic ecosystem containing teleost fishes and water snails biologically stable for several month and to eliminate waste products deriving from degraded dead fishes without a decrease of the oxygen concentration down to less than 3.5 mg/l at 25 °C. More advanced C.E.B.A.S. filter systems, the BIOCURE filters, were also developed for utilization in semiintensive and intensive aquaculture systems for fishes. In fact such combined animal-plant aquaculture systems represent highly effective productions sites for human food if proper plant and fish species are selected The present papers elucidates ways to novel aquaculture systems in which herbivorous fishes are raised by feeding them with plant biomass produced in the BIOCURE filters and presents the scheme of a modification which utilizes a plant species suitable also for human nutrition. Special attention is paid to the benefits of closed aquaculture system modules which may be integrated into bioregenerative life support systems of a higher complexity for, e. g.. lunar or planetary bases including some psychologiccal aspects of the introduction of animal protein production into plant-based life support systems. Moreover, the basic reproductive biological problems of aquatic animal breeding under reduced gravity are explained leading to a disposition of essential research programs in this context.

  17. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2007-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Each chapter ends with a set

  18. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2011-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Ea

  19. Characterizing the structural diversity of a bacterial community associated with filter materials in recirculating aquaculture systems of Scortum barcoo.

    Science.gov (United States)

    Zhu, Peng; Ye, Yangfang; Pei, Fangfang; Lu, Kaihong

    2012-03-01

    The bacterial community structure associated with filter materials in the recirculating aquaculture system of Scortum barcoo was investigated using the 16S rRNA gene clone library method. Preliminary results showed that the clone library constructed from the initial operation condition was characterized by 31 taxa of bacteria belonging to eight phyla including Proteobacteria, Acidobacteria, Firmicutes, Fusobacteria, Sphingobacteria, Bacteroidetes, Verrucomicrobiae, and Actinobacteria. There were 14 taxa of bacteria belonging to four phyla including Proteobacteria, Acidobacteria, Planctomycetacia, and Nitrospirae from the stable operation condition where the water quality was well maintained. Nitrospirae was only found under the stable operation condition in this study. Our results further indicated that Nitrospira was dominated by members of the Nitrospira sp. lineages, with a minor fraction related to Nitrospira moscoviensis and an unknown Nitrospira cluster. These great differences of both diversity and composition between two operation conditions suggested that the composition of the microbial community varied with the degree of water quality in the recirculating aquaculture system of S. barcoo. PMID:22339297

  20. Effectiveness of Floating Micro-Bead Bio-Filter for Ornamental Fish in a Re-Circulating Aquaculture System

    Directory of Open Access Journals (Sweden)

    R Fadhil

    2011-01-01

    Full Text Available Bio-filtration has been widely used in re-circulating aquaculture system to remove waste and to convert toxic ammonia andnitrite into safe end products ornamental fish and other aquatic organisms. However, the study of micro-bead usage as the filter medium has not yet been broadened and thoroughly developed. Therefore, the aim of this study is to construct a biological filter made from polyethylene micro-bead as the filter medium and to analyze its effectiveness in removingwaste as well as in converting the toxic organic matter into stable substances. The bio-filter was constructed under a rotational molding process. The tubes, hoses, and piping were made from polyvinyl chloride (PVC while the fasteners were made from stainless steel and other non-corrosive materials. The effectiveness of this bio-filter was measured by using biochemical oxygen demand (BOD and total suspended solids (TSS analysis. Results indicated that this bio-filter is efficient enough to remove suspended solids and BOD. Therefore, this floating micro-bead bio-filter can be used in aquaculture systems.

  1. The influence of different stocking densities on biochemical composition of rainbow trout meat reared in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Mirela Cretu

    2014-05-01

    Full Text Available The aim of this study is to evaluate the biochemical composition of rainbow trout meat, reared in a recirculating aquaculture system, at different stocking densities (DS1-2,64 kg/m3, DS2-5,16 kg/m3, DS3-7,12 kg/m3, DS4-9,42 kg/m3. The analyses were performed in the research laboratory of Aquaculture, Environmental Science and Cadastre Department – Faculty of Food Science and Engineering, from ,,Dunarea de Jos’’University of Galati. The content of meat proteins, fats, dry substance and ash was determined. After a 33 days experimental trial, the biochemical analysis of meat from all four experimental variants shows that protein content was higher in DS1 and DS4 variants, while the smallest amount of fats was quantified at DS1 and DS2 variants, without significant differences (p >0.05 for none of the biochemical compounds analyzed, at the mean comparison on experimental variants. Thus, it can be concluded that biochemical composition of rainbow trout meat was not influenced by the tested stocking densities.

  2. Foam fractionation efficiency for particulate matter removal from a low salinity, lowhead recirculating aquaculture system utilized for the culture of red drum, Sciaenops ocellatus

    Science.gov (United States)

    In recirculating aquaculture systems (RAS), the water which is treated and reused must be of such quality to maintain the culture organism in a healthy and fast growing condition, especially as such systems are intensified. Managing particulate matter and different chemical compounds is a key factor...

  3. Production of market-size North American strain Atlantic salmon Salmo salar in a land-based recirculation aquaculture system using freshwater

    Science.gov (United States)

    There is interest in culturing Atlantic salmon Salmo salar to market-size in land-based, closed containment systems that use recirculation aquaculture systems (RAS), as this technology often enables facilities to locate near major markets, obtain permits, exclude obligate pathogens, and/or reduce en...

  4. Enhancement of Anaerobic Digestion to Treat Saline Sludge from Recirculating Aquaculture Systems

    Directory of Open Access Journals (Sweden)

    Guo-zhi Luo

    2015-01-01

    Full Text Available The effectiveness of carbohydrate addition and the use of ultrasonication as a pretreatment for the mesophilic anaerobic digestion of saline aquacultural sludge was assessed. Analyses were conducted using an anaerobic sequencing batch reactor (ASBR, which included stopped gas production attributed to the saline inhibition. After increasing the C : N ratio, gas production was observed, and the total chemical oxygen demand (TCOD removal efficiency increased from 75% to 80%. The TCOD removal efficiency of the sonication period was approximately 85%, compared to 75% for the untreated waste. Ultrasonication of aquaculture sludge was also found to enhance the gas production rate and the TCOD removal efficiency. The average volatile fatty acid (VFA to alkalinity ratios ranged from 0.1 to 0.05, confirming the stability of the digesters. Furthermore, soluble chemical oxygen demand (SCOD, VFA, and PO43- concentrations increased in the effluents. There was a 114% greater gas generation during the ultrasonication period, with an average production of 0.08 g COD/L·day−1.

  5. Enhancement of Anaerobic Digestion to Treat Saline Sludge from Recirculating Aquaculture Systems

    Science.gov (United States)

    Luo, Guo-zhi; Ma, Niannian; Li, Ping; Tan, Hong-xin; Liu, Wenchang

    2015-01-01

    The effectiveness of carbohydrate addition and the use of ultrasonication as a pretreatment for the mesophilic anaerobic digestion of saline aquacultural sludge was assessed. Analyses were conducted using an anaerobic sequencing batch reactor (ASBR), which included stopped gas production attributed to the saline inhibition. After increasing the C : N ratio, gas production was observed, and the total chemical oxygen demand (TCOD) removal efficiency increased from 75% to 80%. The TCOD removal efficiency of the sonication period was approximately 85%, compared to 75% for the untreated waste. Ultrasonication of aquaculture sludge was also found to enhance the gas production rate and the TCOD removal efficiency. The average volatile fatty acid (VFA) to alkalinity ratios ranged from 0.1 to 0.05, confirming the stability of the digesters. Furthermore, soluble chemical oxygen demand (SCOD), VFA, and PO43− concentrations increased in the effluents. There was a 114% greater gas generation during the ultrasonication period, with an average production of 0.08 g COD/L·day−1. PMID:26301258

  6. Influence of Fishmeal-Free Diets on Microbial Communities in Atlantic Salmon (Salmo salar) Recirculation Aquaculture Systems

    Science.gov (United States)

    Schmidt, Victor; Davidson, John; Summerfelt, Steven

    2016-01-01

    ABSTRACT Reliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and causing price instability. Alternative diet formulations without the use of fishmeal provide a potential solution to this challenge. Although the impact of alternative diets on fish performance, intestinal inflammation, palatability, and gut microbiota has been a topic of recent interest, less is known about how alternative feeds impact the aquaculture environment as a whole. The recent focus on recirculating aquaculture systems (RAS) and the closed-containment approach to raising food fish highlights the need to maintain stable environmental and microbiological conditions within a farm environment. Microbial stability in RAS biofilters is particularly important, given its role in nutrient processing and water quality in these closed systems. If and how the impacts of alternative feeds on microbial communities in fish translate into changes to the biofilters are not known. We tested the influence of a fishmeal-free diet on the microbial communities in RAS water, biofilters, and salmon microbiomes using high-throughput 16S rRNA gene V6 hypervariable region amplicon sequencing. We grew Atlantic salmon (Salmo salar) to market size in six replicate RAS tanks, three with traditional fishmeal diets and three with alternative-protein, fishmeal-free diets. We sampled intestines and gills from market-ready adult fish, water, and biofilter medium in each corresponding RAS unit. Our results provide data on how fish diet influences the RAS environment and corroborate previous findings that diet has a clear influence on the microbiome structure of the salmon intestine, particularly within the order Lactobacillales (lactic acid bacteria). We conclude that the strong stability of taxa likely involved in water quality processing regardless

  7. Electronic components and systems

    CERN Document Server

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

  8. Stressing fish in Recirculating Aquaculture Systems (RAS): Does stress induced in one group of fish affect the feeding motivation of other fish sharing the same RAS?

    NARCIS (Netherlands)

    Martins, C.I.; Eding, E.H.; Verreth, J.A.J.

    2011-01-01

    As a consequence of water re-use and high stocking densities, Recirculating Aquaculture Systems (RAS) may lead to an accumulation of substances released by the fish into the water, e.g. cortisol and alarm pheromones. This study investigated the effect of stressing fish on the feeding motivation of o

  9. Comparing the effects of high vs. low nitrate on the health, performance, and welfare of juvenile rainbow trout Oncorhynchus mykiss within water recirculating aquaculture systems

    Science.gov (United States)

    Previous research indicates that rainbow trout (Oncorhynchus mykiss) begin to exhibit health and welfare problems when cultured within water recirculating aquaculture systems (WRAS) operated at low exchange (6.7 days hydraulic retention time) and a mean feed loading rate of 4.1 kg feed/m3 daily make...

  10. Production characteristics of body composition of Florida pompano reared to market size at two different densities in low salinity recirculating aquaculture systems

    Science.gov (United States)

    The effect of culture density on production characteristics and body composition of Florida pompano Trachinotus carolinus reared to market size using recirculating aquaculture systems (RAS) at a salinity of 5 g/L was evaluated in a 110 day growth trial (water temperature, 27.0-28.5 C). Juvenile pom...

  11. Evaluation of ozonation on levels of the off-flavor compounds geosmin and 2-methylisoborneol in water and rainbow trout Oncorhynchus mykiss from water recirculation aquaculture systems

    Science.gov (United States)

    Common “off-flavors” in fish cultured in water recirculation aquaculture systems (WRAS) are “earthy” and “musty” due to the presence of the off-flavor metabolites geosmin and 2-methylisoborneol (MIB), respectively. Previously, ozone addition has been applied to WRAS at relatively low doses to break...

  12. Evaluating standard operating procedures to mitigate off-flavor from Atlantic salmon Salmo salar cultured in a semi-commercial scale recirculating aquaculture system

    Science.gov (United States)

    Fish cultured within water recirculating aquaculture systems (RAS) can acquire “earthy” or “musty” off-flavors due to bioaccumulation of the compounds geosmin and 2-methylisoborneol (MIB), respectively, which are produced by certain bacterial species present in RAS biosolids and microbial biofilms. ...

  13. Evaluation of depuration procedures to mitigate off-flavor from harvest size Atlantic Salmon Salmo Salar cultured in a land-based recirculating aquaculture system

    Science.gov (United States)

    Fish cultured within water recirculating aquaculture systems (RAS) can develop “earthy” or “musty” off-flavors in their flesh due to the bioaccumulation of the compounds geosmin and 2-methylisoborenol (MIB), respectively, that are produced by certain bacteria (e.g., actinomycetes). These bacteria an...

  14. The effect of temperature and pH on the growth and physiological response of juvenile yellowtail kingfish Seriola lalandi in recirculating aquaculture systems

    NARCIS (Netherlands)

    Abbink, W.; Blanco Garcia, A.; Roques, J.A.C.; Partridge, G.; Kloet, K.; Schneider, O.

    2012-01-01

    A search for a viable new fish species for culture in recirculating aquaculture systems (RAS) in the Netherlands identified yellowtail kingfish Seriola lalandi as having excellent potential. To assist in determining the most appropriate water quality conditions for this species in RAS, the effect of

  15. The influence of stocking density on the growth of common carp, Cyprinus carpio, in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Ionica Enache

    2011-04-01

    Full Text Available The paper presents some aspects regarding the influence of stocking density on the breeding of the common carp in a recirculating aquaculture system (RAS. The experiment covered a 30 dayperiod. It was conducted in four aquaculture tanks, 500 L/tank, in the recirculating aquaculture pilot system of “Dunarea de Jos” University of Galați. Two kind of stocking density variants were compared: 64 kg/m3 in V1 (B1, B3 and 32 kg/m3 in V2 (B2, B4. The stocking density was: 491 fish in B1, average weight - 65 g/ fish; 245 fish in B2, average weight - 66 g/ fish; 211 fish in B3, average weight - 152 g/fish; 107 fish in B4, average weight - 150 g/fish. The technological indicators obtained revealed the following: the specific growth rate (SGR, calculated as a mean value on the two repetitions, was 1.28%/day in V1 and 1.49 %/day in V2, indicating better growth in V2; the food conversion ratio (FCR, calculated as the mean value of the two repetitions, was 1.28 in V1 and 1.06 in V2, expressing a higher efficiency in capitalization of food in V2. The mean biomass gain in V1 was 30.46 kg/m3 as compared to 18.55 kg/m3 in V2, almost perfectly correlated with the stocking density. The daily growth rate (DGR varied in a similar way, from 494.57 to 520.90 g/day in V1 and 302.4 to 315.9 g/day in V2. The experiment demonstrated a remarkable technological plasticity in both experimental variants, whereas, in terms of technological performance indicators, it was found that the application of lower stocking densities lead to higher crop biomass. The high stocking density means, therefore, large amounts of metabolic waste, removed from the breeding units through their effluent, the recirculating flow of which is 4m3/h, enough to ensure the whole volume of water in a growth tank to be changed every half hour.

  16. An Overview of Aquaculture in the Nordic Countries

    DEFF Research Database (Denmark)

    Paisley, Larry; Ariel, Ellen; Lyngstad, T. M.;

    2010-01-01

    The goal of this review was to describe in some detail the Nordic aquaculture industries in order to illuminate the similarities and differences. Information that was gathered for each country includes aquaculture history, aquaculture acts and regulations, production and production systems......, environmental concerns, organic aquaculture and outlook for the future. The information will be useful for risk assessments, design of risk-based surveillance programs and for construction of comparative risk profiles for endemic and exotic diseases affecting aquaculture in the Nordic countries. Aquaculture...... char and cod are most important in Iceland. Other important cultured species include eel and blue mussels. There is much diversity in Nordic aquaculture industries in terms of production, farmed species, and production systems. Although the vast majority of the Nordic aquaculture production...

  17. Automatic technology in a recirculating aquaculture system%工厂化水产养殖中的自动控制技术

    Institute of Scientific and Technical Information of China (English)

    曹广斌; 蒋树义; 韩世成; 陈忠祥

    2011-01-01

    本文从工厂化水产养殖自动控制系统的组成、自动控制方法、自动控制技术在水质参数检测与调控中的应用等方面,论述了有关研究的技术成果和未来发展趋势.根据水产养殖工业化和自动化发展,以及自动控制技术在水产养殖中的广阔应用前景,指出了发展水产养殖自动化检测和调控精准技术的必要性,提出发展规范化、标准化的水产养殖自动化技术,以推动水产养殖工业化的发展.%The research and development of an automatic control system are summarized in the recirculating aquaculture, including the components of the system, the method of control, and the application of automatic technology in aquaculture.According to the need of aquaculture and the wide perspective application, it is necessary to research advanced automatic technology and to establish some standards for application of the technology in the recirculating aquaculture system.

  18. Public, animal, and environmental health implications of aquaculture.

    OpenAIRE

    Garrett, E. S.; C.L. dos Santos; Jahncke, M. L.

    1997-01-01

    Aquaculture is important to the United States and the world's fishery system. Both import and export markets for aquaculture products will expand and increase as research begins to remove physiologic and other animal husbandry barriers. Overfishing of wild stock will necessitate supplementation and replenishment through aquaculture. The aquaculture industry must have a better understanding of the impact of the "shrouded" public and animal health issues: technology ignorance, abuse, and neglec...

  19. MDT DCS Electronics System

    CERN Document Server

    Tsarouchas, Charilaos; Gazis, Evangelos; Tsipolitis, Georgios

    This note has the aim to present the Detector Control System for the Monitor- ing of the electronics values of MDT chambers in ATLAS experiment in CERN. This system is decided to be called in short ELTX. The principal task of DCS is to enable and ensure the coherent and safe oper- ation of the detector. The interaction of detector expers, users or shifters to the detector hardware is also done via DCS. This is the responsible system of moni- toring the operational parameters and the overall state of the detector, the alarm generation and handling, the connection of hardware values to databases and the interaction with the DAQ system. Through this thesis, one can see what ELTX system has to offer as a Detector Control System and in detail, what is the hardware to be controlled and monitored. Moreover it is presented the mainstream of central Atlas DCS concerning the active interfaces.ELTX is a system following these standards.

  20. Analyzing and Evaluating of Recirculating Aquaculture Systems (RAS) of Rainbow Trout in Order to Designing a Conceptual Model of Efficient RAS in Iran (Tehran)

    OpenAIRE

    M. Mahmoodzadeh; M Almassi; A.M. Borghei; B. Beheshti

    2013-01-01

    In this study, Recirculation Aquaculture Systems (RAS) of rainbow trout were analyzed and evaluated in Iran (Tehran). After analyzing these systems it was found which of them were better than others and then their parameters were used for designing a conceptual model of efficient RAS. This study was conducted in Iran (Tehran) in 2012 and statistical population and samples were 8 systems. Systems were analyzed and evaluated by five criteria which were as follows: economy, energy, consumption a...

  1. Establishment of a real-time PCR method for quantification of geosmin-producing Streptomyces spp. in recirculating aquaculture systems.

    Science.gov (United States)

    Auffret, Marc; Pilote, Alexandre; Proulx, Emilie; Proulx, Daniel; Vandenberg, Grant; Villemur, Richard

    2011-12-15

    Geosmin and 2-methylisoborneol (MIB) have been associated with off-flavour problems in fish and seafood products, generating a strong negative impact for aquaculture industries. Although most of the producers of geosmin and MIB have been identified as Streptomyces species or cyanobacteria, Streptomyces spp. are thought to be responsible for the synthesis of these compounds in indoor recirculating aquaculture systems (RAS). The detection of genes involved in the synthesis of geosmin and MIB can be a relevant indicator of the beginning of off-flavour events in RAS. Here, we report a real-time polymerase chain reaction (qPCR) protocol targeting geoA sequences that encode a germacradienol synthase involved in geosmin synthesis. New geoA-related sequences were retrieved from eleven geosmin-producing Actinomycete strains, among them two Streptomyces strains isolated from two RAS. Combined with geoA-related sequences available in gene databases, we designed primers and standards suitable for qPCR assays targeting mainly Streptomyces geoA. Using our qPCR protocol, we succeeded in measuring the level of geoA copies in sand filter and biofilters in two RAS. This study is the first to apply qPCR assays to detect and quantify the geosmin synthesis gene (geoA) in RAS. Quantification of geoA in RAS could permit the monitoring of the level of geosmin producers prior to the occurrence of geosmin production. This information will be most valuable for fish producers to manage further development of off-flavour events.

  2. Cooling system for electronic components

    Science.gov (United States)

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  3. Cooling system for electronic components

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2016-05-17

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  4. Chemical composition and antimicrobial activity of the essential oil of Syzygium aromaticum flower bud (Clove) against fish systemic bacteria isolated from aquaculture sites

    Institute of Scientific and Technical Information of China (English)

    Seongwei LEE; Musa NAJIAH; Wee WENDY; Musa NADIRAH

    2009-01-01

    This paper describes the chemical composition and antimicrobial activity of the essential oil of Syzygium aromaticum against Vibrio spp. (n=6), Edwardsiella spp. (n=21), Aeromonas spp. (n=2), Escherichia coli (n=2), Flavobacterium spp. (n=1), Salmonella spp. (n=2), Streptococcus spp. (n=1) and Pseudomonas spp. (n=1) isolated from aquaculture sites as well as seven reference strains of bacteria, namely, Escherichia coli (ATCC 25922), Citrobacter freundii (ATCC 8090), Aeromonas hydrophila (ATCC 49140), Pseudomonas aeruginosa (ATCC 35032), Streptococcus agalactiae (ATCC13813), Edwardsiella tarda (ATCC 15947) and Yersinia enterocolitica (ATCC 23715). Nowadays, most antibiotics are no longer effective in controlling diseases in aquaculture, especially fish systemic bacterial diseases, due to increasing incidences of antibiotic resistance among pathogenic bacteria. Furthermore, many countries have banned antibiotics in aquaculture use due to public health concerns and environmental hazards. Therefore, this study was carried out to evaluate the potential of the essential oil of S. aromaticum as an alternate commercial antibiotic to antimicrobial agents against fish systemic bacteria in aquaculture. The essential oil of S. aromaticum was prepared using a steam distillation method, and the chemical composition was analysed using Gas chromatography-mass spectroscopy (GC-MS). Minimum inhibitory concentration (MIC) values of the essential oils against the tested bacteria were determined using the broth two fold micro dilution method, with kanamycin and eugenol as positive controls. The MIC values of the essential oil of S. aromaticum ranged from 0.015 μg·mL-1 to 0.062 μg·mL-1 against the tested bacterial isolates. A total of nine chemical compounds were detected in the essential oil, with eugenol (49.0%) and caryophyllene (7.5%) being the major compounds. The results of the present study indicate that the essential oil of S. aromati- cum shows a huge potential to

  5. Aquaculture and food crisis: opportunities and constraints.

    Science.gov (United States)

    Liao, I Chiu; Chao, Nai-Hsien

    2009-01-01

    Fish farming, now well known as aquaculture, has been well recognized since the ancient era. The first written document on fish culture was published in China in 475 BC, and the first koi pond was constructed at the Japanese Imperial Palace grounds during 71-130 AD. In recent years, aquaculture has progressively played an important role in the provision of: animal protein and gourmet cuisines, job opportunities, and foreign currency for developing countries. Asian countries produce around 91 percent of the world's total aquaculture production. Among the top ten aquaculture-producing countries, nine are from Asia. The current global population consist of more than 6.5 billion individuals; over one billion of which face hunger problem. In the highly populated Asia-Pacific region with moderately high-productivity, 642 million people are still facing hunger. Being a proficient and potential source of animal protein, aquaculture will play an increasing and important role in solving the world food problem in the future. This paper discusses both the opportunities and constraints in the aquaculture industry, specifically in the Asia-Pacific region, and its possible role in solving the current global food crisis. Strategies including promotion and adoption of traceability and HACCP systems for food safety, and marketing management for aquaculture products are also suggested. It is hoped that traditional administration of aquaculture management for survival, profit, as well as food safety will successfully match sustainability management to meet the urgent global need for food.

  6. Cultivable intestinal microbiota of yellowtail juveniles (Seriola lalandi in an aquaculture system

    Directory of Open Access Journals (Sweden)

    Eduardo Aguilera

    2013-07-01

    Full Text Available The yellowtail (Seriola lalandi has been farmed for many years and is becoming a promising aquaculture species. Knowledge of the intestinal microbiota of this species is very limited. Thus, the aim of this study is to describe the bacterial populations associated with the intestinal tract of Seriola lalandi reared in Chile. The microbiota composition was analyzed at two growth stages distinguished by weight and parameters such as Specific Growth Rate (SGR and Feed Conversion Ratio (FCR. Juveniles (mean initial weight 7.33 ± 0.30 g and pre-adults (81.7 ± 19.0 g were fed with commercial diet for 33 and 50 days, respectively. The first intestinal samples were collected at the end of Trial 1 from specimens weighing approximately 50 g while the second samples were obtained at the end of Trial 2 from specimens weighing approximately 370 g. The microbiota composition was examined using conventional isolation in Tryptic Soy Agar (TSA followed by 16S rRNA sequencing and identification. In total, 16 genera were identified. Pseudomonas, Vibrio and Staphylococcus were the predominant genera in fish at the 50 g stage, whereas Microbacterium and Francisella were the predominant genera in the 370 g stage. The microbiota composition showed different assemblages, depending on host size, with Bacillus and Vibrio being the only genera that were shared. Knowledge of the intestinal microbiota of Seriola lalandi is the first step in the exploration of microbiota management and the development of probiotics, as well as in the identification of the bacterial populations in healthy fish under cultured conditions.

  7. The Development of a Renewable-Energy-Driven Reverse Osmosis System for Water Desalination and Aquaculture Production

    Institute of Scientific and Technical Information of China (English)

    Clark C K Liu

    2013-01-01

    Water and energy are closely linked natural resources-the transportation, treatment, and distribution of water depends on low-cost energy;while power generation requires large volumes of water. Seawater desalination is a mature technology for increasing freshwater supply, but it is essentially a trade of energy for freshwater and is not a viable solution for regions where both water and energy are in short supply. This paper discusses the development and application of a renewable-energy-driven reverse osmosis (RO) system for water desalination and the treatment and reuse of aquaculture wastewater. The system consists of (1) a wind-driven pumping subsystem, (2) a pressure-driven RO membrane desalination subsystem, and (3) a solar-driven feedback control module. The results of the pilot experiments indicated that the system, operated under wind speeds of 3 m s-1 or higher, can be used for brackish water desalination by reducing the salinity of feedwater with total dissolved solids (TDS) of over 3 000 mg L-1 to product water or permeate with a TDS of 200 mg L-1 or less. Results of the pilot experiments also indicated that the system can remove up to 97%of the nitrogenous wastes from the fish pond effluent and can recover and reuse up to 56%of the freshwater supply for fish pond operation.

  8. Molecular Analysis of Bacterial Communities and Detection of Potential Pathogens in a Recirculating Aquaculture System for Scophthalmus maximus and Solea senegalensis

    OpenAIRE

    Patrícia Martins; Cleary, Daniel F. R.; Pires, Ana C. C.; Ana Maria Rodrigues; Victor Quintino; Ricardo Calado; Gomes, Newton C M

    2013-01-01

    The present study combined a DGGE and barcoded 16S rRNA pyrosequencing approach to assess bacterial composition in the water of a recirculating aquaculture system (RAS) with a shallow raceway system (SRS) for turbot (Scophthalmus maximus) and sole (Solea senegalensis). Barcoded pyrosequencing results were also used to determine the potential pathogen load in the RAS studied. Samples were collected from the water supply pipeline (Sup), fish production tanks (Pro), sedimentation filter (Sed), b...

  9. RESEARCHES REGARDING THE TECHNOLOGICAL PERFORMANCES OF CARP REARING DURING WINTER PERIOD IN THE CONDITIONS OF A RECIRCULATING AQUACULTURE SYSTEM

    Directory of Open Access Journals (Sweden)

    G. STEFAN

    2013-12-01

    Full Text Available The techniques of carp culture are highly diversified, ranging from the extensive production in pond or open water with no fertilization or supplemental feeding to highly intensive systems in concrete tanks or cages. Among the different carp species, common carp is the best species reared in intensive monoculture, the others (Chinese and Indian carps being usually cultivated in polyculture (P. Kestemont, 1995. An experiment was conducted in inside recirculation system conditions to identify the technological performances on carp growth and survival at the Fishing and Aquaculture Department, Galati, during winter period (February, 2007 – March, 2007. The 1-year-old carp (Cyprinus carpio 4792g; 4594 g; 4561 g and 4525 g (total weight grew to 7384g; 7017g; 6924g and 7125 g in 44 days in aquarium 1, 2, 3 and 4, respectively. In all aquariums, the fish appeared healthy and no mortality was observed. Feed conversion efficiencies (FCE had similar values among all aquariums, the highest FCE being found in B4 aquarium with 1, 57 value. Water quality parameters were acceptable range for fish culture. Results show that the carp rearing during winter period in the inside recirculation system is a very good economic solution.

  10. Investigating the effectiveness of peracetic acid to reduce post-vaccination Saprolegnia spp.-associated mortality in Atlantic salmon parr while assessing impact on nitrification in recirculation aquaculture systems

    Science.gov (United States)

    Closed containment operations utilizing recirculation aquaculture systems (RAS) can provide critical barriers to the introduction of obligate fish pathogens (Timmons and Ebeling, 2010); however, opportunistic pathogens will be present and can cause disease when conditions favor these agents. One par...

  11. Effect of Hydraulic Loading Rate on the Efficiency of Effluent Treatment in a Recirculating Puffer Aquaculture System Coupled with Constructed Wetlands

    Institute of Scientific and Technical Information of China (English)

    XU Jiabo; SHI Yonghai; ZHANG Genyu; LIU Jianzhong; ZHU Yazhu

    2014-01-01

    Constructed wetlands (CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer (Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate (HLR) on the efficiency of effluent treatment by CWs was ex-amined for over a month. The CWs were operated under brackish conditions (salinity 7.4-7.6) at 3 different HLRs (0.762, 0.633, and 0.458 m d-1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen (by 81.03-92.81%) and nitrite nitrogen (by 99.40%-99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids (TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.

  12. Impact of water boundary layer diffusion on the nitrification rate of submerged biofilter elements from a recirculating aquaculture system.

    Science.gov (United States)

    Prehn, Jonas; Waul, Christopher K; Pedersen, Lars-Flemming; Arvin, Erik

    2012-07-01

    Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS's. The aim of this study was to determine the impact of hydraulic film diffusion on the nitrification rate in a submerged biofilter. Using an experimental batch reactor setup with recirculation, active nitrifying biofilter units from a RAS were exposed to a range of hydraulic flow velocities. Corresponding nitrification rates were measured following ammonium chloride, NH₄Cl, spikes and the impact of hydraulic film diffusion was quantified. The nitrification performance of the tested biofilter could be significantly increased by increasing the hydraulic flow velocity in the filter. Area based first order nitrification rate constants ranged from 0.065 m d⁻¹ to 0.192 m d⁻¹ for flow velocities between 2.5 m h⁻¹ and 40 m h⁻¹ (18 °C). This study documents that hydraulic film diffusion may have a significant impact on the nitrification rate in fixed film biofilters with geometry and hydraulic flows corresponding to our experimental RAS biofilters. The results may thus have practical implications in relation to the design, operational strategy of RAS biofilters and how to optimize TAN removal in fixed film biofilter systems. PMID:22507250

  13. Ammonia-oxidizing archaea and nitrite-oxidizing nitrospiras in the biofilter of a shrimp recirculating aquaculture system.

    Science.gov (United States)

    Brown, Monisha N; Briones, Aurelio; Diana, James; Raskin, Lutgarde

    2013-01-01

    This study analysed the nitrifier community in the biofilter of a zero discharge, recirculating aquaculture system (RAS) for the production of marine shrimp in a low density (low ammonium production) system. The ammonia-oxidizing populations were examined by targeting 16S rRNA and amoA genes of ammonia-oxidizing bacteria (AOB) and archaea (AOA). The nitrite-oxidizing bacteria (NOB) were investigated by targeting the 16S rRNA gene. Archaeal amoA genes were more abundant in all compartments of the RAS than bacterial amoA genes. Analysis of bacterial and archaeal amoA gene sequences revealed that most ammonia oxidizers were related to Nitrosomonas marina and Nitrosopumilus maritimus. The NOB detected were related to Nitrospira marina and Nitrospira moscoviensis, and Nitrospira marina-type NOB were more abundant than N. moscoviensis-type NOB. Water quality and biofilm attachment media played a role in the competitiveness of AOA over AOB and Nitrospira marina-over N. moscoviensis-type NOB. PMID:22775980

  14. Disease in marine aquaculture

    Science.gov (United States)

    Sindermann, C. J.

    1984-03-01

    populations. Some progress has been made in marine disease control through chemical treatment in intensive culture systems, principally through application and modification of methods developed for freshwater aquaculture. Major constraints to use of chemicals are restrictions due to public health concerns about food contamination, and the negative effects of some chemicals on biological filters and on algal food production. There is a continuing need, however, for development of specific treatments for acute disease episodes — such as the nitrofurans, developed in Japan, which are effective for some bacterial diseases. The history of aquaculture — freshwater as well as marine — has been characterized by transfers and introductions of species to waters beyond their present ranges. The process continues, and carries with it the possibility of transfers of pathogens to native species and to the recipient culture environments. International groups are attempting to define codes of practice to govern such mass movements, but examples of introductions of real or potential pathogens already exist. The most recent and the most dramatic is the world wide transfer of a virus pathogen of penaeid shrimps. Earlier examples include the introduction of a protozoan pathogen of salmonids to the western hemisphere, and the introduction of a parasitic copepod from the Far East to the west coast of North America and to France. The conclusion is inevitable — diseases are substantial deterrents to aquaculture production. Diagnostic and control procedures are and will be important components of emerging aquaculture technology.

  15. Effect of Recirculating Aquaculture System (RAS) on Growth Performance, Body Composition and Hematological Indicators of Allogynogenetic crucian Carp (Carassius auratus gibelio)

    OpenAIRE

    Xiao-li Li; Gu Li; Shi-yang Zhang; Ling Tao

    2013-01-01

    A Ditch Constructed Wetland unit (DCW) was integrated into an outdoor RAS with four fishponds. This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of Recirculating Aquaculture System (RAS) on growth performance, body composition and hematological indicators of the rearing fish. During a 165-days culture period, the DCW effectively reduced the influent concentrations of nutrients and can keep a good water quality at acceptab...

  16. Biological denitrification using poly(butylene succinate) as carbon source and biofilm carrier for recirculating aquaculture system effluent treatment.

    Science.gov (United States)

    Zhu, Song-Ming; Deng, Ya-Le; Ruan, Yun-Jie; Guo, Xi-Shan; Shi, Ming-Ming; Shen, Jia-Zheng

    2015-09-01

    Nitrate removal is essential for the sustainable operation of recirculating aquaculture system (RAS). This study evaluated the heterotrophic denitrification using poly(butylene succinate) as carbon source and biofilm carrier for RAS wastewater treatment. The effect of varied operational conditions (influent type, salinity and nitrate loading) on reactor performance and microbial community was investigated. The high denitrification rates of 0.53 ± 0.19 kg NO3(-)-N m(-3) d(-1) (salinity, 0‰) and 0.66 ± 0.12 kg NO3(-)-Nm(-3) d(-1) (salinity, 25‰) were achieved, and nitrite concentration was maintained below 1mg/L. In addition, the existence of salinity exhibited more stable nitrate removal efficiency, but caused adverse effects such as excessive effluent dissolved organic carbon (DOC) and dissimilation nitrate reduce to ammonia (DNRA) activity. The degradation of PBS was further confirmed by SEM and FTIR analysis. Illumina sequencing revealed the abundance and species changes of functional denitrification and degradation microflora which might be the primary cause of varied reactor performance. PMID:26093254

  17. The effects of different seeding ratios on nitrification performance and biofilm formation in marine recirculating aquaculture system biofilter.

    Science.gov (United States)

    Zhu, Songming; Shen, Jiazheng; Ruan, Yunjie; Guo, Xishan; Ye, Zhangying; Deng, Yale; Shi, Mingming

    2016-07-01

    Rapid start-up of biofilter is essential for intensive marine recirculating aquaculture system (RAS) production. This study evaluated the nitrifying biofilm formation using mature biofilm as an inoculum to accelerate the process in RAS practice. The effects of inoculation ratios (0-15 %) on the reactor performance and biofilm structure were investigated. Complete nitrification was achieved rapidly in reactors with inoculated mature biofilm (even in 32 days when 15 % seeding ratio was applied). However, the growth of target biofilm on blank carrier was affected by the mature biofilm inoculated through substrate competition. The analysis of extracellular polymeric substance (EPS) and nitrification rates confirmed the divergence of biofilm cultivation among reactors. Besides, three N-acyl-homoserine lactones (AHLs) were found in the process, which might regulate the activities of biofilm. Multivariate analysis based on non-metric multidimensional scaling (nMDS) also indicated the great roles of AHLs and substrate supply which might fundamentally determine varied cultivation performance on target biofilm. PMID:27068911

  18. The Effects of Some Phytobiotics on Biochemical Composition of Oreochromis Niloticus Meat Reared in a Recirculating Aquaculture System

    Directory of Open Access Journals (Sweden)

    Alina Antache

    2013-05-01

    Full Text Available The purpose of this experiment is the evaluation of biochemical composition of Nile tilapia meat by administrating  several phytobiotics in feed. Oreochromis niloticus, with an initial average weight of 125.41±34.33 g/exemplar, were reared, during six weeks in a recirculating aquaculture system. The phytobiotics from this experiment were administered in feed in a concentration of 1%/kg feed and consist in: thyme (Thymus vulgaris, fenugreek (Trigonela foenum graecum, neem (Azadirachta indica. Thus, the experimental variants were: V1-control, V2-thyme, V3-fenugreek and V4-neem. Fish were fed with SOPROFISH pelleted feed with 38% crude protein and 7% crude fat. During the experiment, the physico-chemical parameters of technological water were situated in normal range for optimal growth. At the end of the experiment, significant differences (p<0.05 were recorded between the experimental variants, regarding to moisture, protein content, fat content and dry matter; unsignificant differences were recorded regarding the percentage of ash (p>0.05; p=0.68. The highest value of moisture (87.25% was registered in V2; the lowest value of fat content (0.05% was recorded in V4 and the lowest protein content (10.79% in V2. In conclusion, thyme, fenugreek and neem administration, in concentration of 1%/kg feed, influenced significantly the biochemical composition of Oreochromis niloticus.

  19. Effects of solid-phase denitrification on the nitrate removal and bacterial community structure in recirculating aquaculture system.

    Science.gov (United States)

    Qiu, Tianlei; Liu, Lili; Gao, Min; Zhang, Lanhe; Tursun, Haireti; Wang, Xuming

    2016-06-01

    A solid-phase denitrification (SPD) reactor packed with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) as a carbon source was incorporated into a recirculating aquaculture system (RAS) to remove accumulated nitrate. Bacterial community structures in different parts of the RAS, including biofilter unit, SPD reactor, and culture water, were analyzed using Illumina MiSeq sequencing technology. The data showed that nitrate levels decreased remarkably in the RAS connected with SPD reactor (RAS-DR). In contrast, nitrate levels increased continuously in the conventional RAS without SPD reactor (RAS-CK). Biofilter unit and culture water in RAS-DR developed lower species richness and higher bacterial community diversity than that in RAS-CK. The bacterial community structure of RAS was significantly affected by the SPD process and the changes included an increase in the proportion of Proteobacteria and Firmicutes and a decrease in Nitrospira abundance in RAS-DR. Firmicutes was the most abundant phylum (56.9 %) and mainly consisted of Clostridium sensu stricto (48.3 %) in SPD reactor. PMID:27125529

  20. Application of CFD Modeling to Hydrodynamics of CycloBio Fluidized Sand Bed in Recirculating Aquaculture Systems

    Institute of Scientific and Technical Information of China (English)

    LIU Yao; SONG Xiefa; LIANG Zhenlin; PENG Lei

    2014-01-01

    To improve the efficiency of a CycloBio fluidized sand bed (CB FSB) in removal of dissolved wastes in recirculating aquaculture systems, the hydrodynamics of solid-liquid flow was investigated using computational fluid dynamics (CFD) modeling tools. The dynamic characteristics of silica sand within the CB FSB were determined using three-dimensional, unsteady-state simula-tions with the granular Eulerian multiphase approach and the RNG k-ε turbulence model, and the simulation results were validated using available lab-scale measurements. The bed expansion of CB FSB increased with the increase in water inflow rate in numerical simulations. Upon validation, the simulation involving 0.55 mm particles, the Gidaspow correlation for drag coefficient model and the Syamlal-O’Brien correlation for kinetic granular viscosity showed the closest match to the experimental results. The volume frac-tion of numerical simulations peaked as the wall was approached. The hydrodynamics of a pilot-scale CB FSB was simulated in or-der to predict the range of water flow to avoid the silica sand overflowing. The numerical simulations were in agreement with the experimental results qualitatively and quantitatively, and thus can be used to study the hydrodynamics of solid-liquid multiphase flow in CB FSB, which is of importance to the design, optimization, and amplification of CB FSBs.

  1. The Relationship between the Area of Aquaculture Pond and Purification Pond in Water Circulation Aquaculture System%池塘循环水养殖模式下养殖面积与净化面积的配比关系研究

    Institute of Scientific and Technical Information of China (English)

    宋超; 陈家长; 戈贤平; 孟顺龙; 范立民; 胡庚东

    2013-01-01

    The establishment of water circulation aquaculture system realized the hierarchical use of nitrogen,phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource.However,no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond.In this study,referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond,based on the general rules of water quality management in freshwater aquaculture system,a calculation mode was established to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system,which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the balance between the ecological benefits and the economic benefits.%池塘循环水养殖模式的构建实现了养殖废水中氮、磷等富营养化物质的分级利用和水资源的循环使用,但此前的研究并没有详细计算养殖面积和净化面积合理的配比关系.通过参照水生植物对养殖尾水中污染物的吸收能力和养殖鱼类的产排污系数,再结合淡水池塘养殖过程中的水质管理的一般规律,给出了淡水池塘循环水养殖模式中养殖池塘面积和净化池塘面积之间配比关系的计算方法.利用该计算方法来解释此前相关的研究实例,也证明是可行的.该计算模型的构建为今后在池塘循环水养殖模式构建中降低经济成本,为最终实现生态效益对经济效益的补偿提供了理论基础.

  2. Leaf vegetables for use in integrated hydroponics and aquaculture systems: Effects of root flooding on growth, mineral composition and nutrient uptake

    DEFF Research Database (Denmark)

    Trang, Ngo Thuy Diem; Schierup, Hans-Henrik; Brix, Hans

    2010-01-01

    In recirculating aquaculture and hydroponics systems, the waste products from fish production are used to produce vegetables or other crops of economic value, and the water is recirculated to the fish tanks. We studied growth, productivity and nutrient uptake of four leaf vegetable species (Lactuca...... sativa, Ipomoea aquatica, Brassica rapa var. chinensis and Brassica rapa var. parachinensis) in a controlled growth experiment with three root flooding treatments (drained, half-flooded and flooded) to assess their preferred hydroponic growth requirements, biomass production and nutrient removal......, respectively. The two Brassica varieties produced much less aerial biomass (50-54 g DW/m2 during a 60-day period). Both I. aquatica and L. sativa are promising species to be included in integrated hydroponic and aquaculture facilities, with I. aquatica showing the most promise because of its higher growth...

  3. Aquaculture in mangrove environment

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A.H.

    A general account of aquaculture of India in mangrove environment has been discussed. In-spite of being a none-too-tidal aquaculture site, the estuaries and backwaters fringEd. by mangrove vegetation have long been used for rearing and fattening...

  4. Comparative analysis of technical efficiency for different production culture systems and species of freshwater aquaculture in Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Abdullahi Iliyasu

    2016-05-01

    Full Text Available This study estimated the bias-corrected technical efficiency (BCTE of different culture systems and species of freshwater aquaculture in Malaysia using bootstrapping data envelopment analysis (DEA. Data were collected from 307 respondents from three states in Peninsular Malaysia using a well-structured questionnaire as well as oral interviews. The findings indicate that all technical efficiency scores for all culture systems and species are below the optimal level (i.e. one. In addition, the results show that farmers’ experience, contact with extension workers and household size have a positive and statistically significant impact on technical efficiency. This implies that farmers who have long tenure in fish farming and also the opportunity to meet with extension workers are operating close to the production frontier (technically efficient. On the other hand, the age of the farmers has a negative and statistically significant impact on technical efficiency. Although educational level and farm status have a positive impact on technical efficiency, they are statistically insignificant. Furthermore, all the inputs used in the production process of different culture systems and species contained slacks and need to be reduced accordingly. Feed, the major input in fish production and constituting over half of the production costs, is equally over-utilized. Thus, the government, in collaboration with research institutes and universities, should design a feeding formula for fish depending on species, culture systems and stages of growth. This could help to reduce production costs, increasing the farmers' income, as well as providing much needed animal protein to consumers at an affordable rate.

  5. Importance of kelp-derived organic carbon to the scallop Chlamys farreri in an integrated multi-trophic aquaculture system

    Science.gov (United States)

    Xu, Qiang; Gao, Fei; Yang, Hongsheng

    2016-03-01

    Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweed-based IMTA system has been confirmed, but the trophic importance of seaweed-derived particulate organic materials to the co-cultured bivalve is still unclear. We evaluated the trophic importance of the kelp Saccharina japonica to the co-cultured scallop Chlamys farreri in a typical IMTA farm in Sungo Bay (Weihai, North China). The dynamics of detritus carbon in the water were monitored during the culturing period. The proportion of kelp-derived organic matter in the diet of the co-cultured scallop was assessed via the stable carbon isotope method. Results showed that the detritus carbon in the water ranged from 75.52 to 265.19 μg/L, which was 25.6% to 73.8% of total particulate organic carbon (TPOC) during the study period. The amount of detritus carbon and its proportion in the TPOC changed throughout the culture cycle of the kelp. Stable carbon isotope analysis showed that the cultured scallop obtained 14.1% to 42.8% of its tissue carbon from the kelp, and that the percentages were closely correlated with the proportion of detritus carbon in the water ( F =0.993, P= 0.003). Evaluation showed that for 17 000 tons (wet weight) of annual scallop production, the kelp contributed about 139.3 tons of carbon (535.8 tons of dry mass). This confirms that cultured kelp plays a similar trophic role in IMTA systems as it does in a natural kelp bed. It is a major contributor to the detritus pool and supplies a vital food source to filter-feeding scallops in the IMTA system, especially during winter and early spring when phytoplankton are scarce.

  6. Nitrogen and Phosphorus Removal in the Recirculating Aquaculture System with Water Treatment Tank containing Baked Clay Beads and Chinese Cabbage

    Directory of Open Access Journals (Sweden)

    Aeknarin Thanakitpairin

    2014-01-01

    Full Text Available This research aims to describe the nitrogen and phosphorus removal in Recirculating Aquaculture System (RAS by crop plants biomass production. The 3 experiment systems consisted of 1 treatment (fish tank + baked clay beads + Chinese cabbage and 2 controls as control-1 (fish tank only and control-2 (fish tank + baked clay beads, were performed. With all experimental RAS, Nile tilapia (Oreochromis niloticus was cultured at 2 kg/m3 density. The baked clay beads (8-16 mm in diameter were filled as a layer of 10 cm in the water treatment tank of control-2. While in the treatment tank, Chinese cabbage (Brassica pekinensis was planted at 334 plants/m2 in baked clay beads layer. During 35 days of experiment, the average fish wet-weight in control-1, control-2 and treatment systems increased from 16.31±1.49, 15.18±1.28 and 11.31±1.49 g to 29.43±7.06, 28.65±3.12 and 27.20±6.56 g, respectively. It was found that the growth rate of 0.45±0.15 g-wet weight/day in a treatment tank was higher than in those 2 controls, which were rather similar at 0.37±0.16 and 0.38±0.05 g-wet weight/day, respectively. The fish survival rate of all experimental units was 100%. The average Chinese cabbage wet-weight in treatment system increased from 0.15±0.02 g to 1.00±0.38 g. For water quality, all parameters were within the acceptable range for aquaculture. The assimilation inorganic nitrogen in a treatment tank showed a slower rate and lower nitrite accumulation relative to those in control tanks. The nitrogen and phosphorus balance analysis illustrated that most of the nitrogen and phosphorus input in all systems was from feed (82-87% and 21-87% while at the final day of experiments, nitrogen and phosphorus in tilapia culture revealed at 15-19% and 4-13%. The accumulation of nitrogen and phosphorus in the water, up to 56% and 70%, was found in control-1 while water in the tank with baked clay beads had substantial lower nitrogen and phosphorus concentration. The

  7. Performance of Nile tilapia Oreochromis niloticus fingerlings in a hyper-intensive recirculating aquaculture system with low water exchange

    Directory of Open Access Journals (Sweden)

    M Gullian-Klanian

    2013-03-01

    Full Text Available The aim of this paper was evaluate the performance of Nile tilapia fingerlings (Oreochromis niloticus raised at hyper intensive stocking density in a recirculating aquaculture system (RAS with minimum water replacing. The experimental system was performed in a single-batch nursery system to obtain 50 g fish size in 60 days. Fish (2.07 ± 0.04 g were stocked in triplicate at 400 (T1, 500 (T2 and 600 (T3 fish m-3 (0.84, 1.05, 1.22 kg m-3. RAS functioned with 12,000 L of recirculating water and 252 L day-1of water replacing (2.1% daily. The efficiency of the biofilter for removing the total ammonia nitrogen (TAN was 48 ± 12.5 mg L-1. Stocking density did not affect significantly the survival (89.5 to 93.6%. The growth rate of T1 (0.96 g day-1; 5.01% day-1 and T2 (0.92 g day-1; 4.95 % day-1 was significantly higher than T3 (0.83 g day-1; 4.80% day-1. The specific growth rate (SGR of T1 was 41% influenced by temperature. For T2 and T3 the SGR were influenced by the variation of dissolved oxygen (DO that explained 47 and 44% of the fish weight variation, respectively. The SGR from T3 was also affected by the concentration of ammonia nitrogen (31%. The high stocking density affected the overall size of fish and the size homogeneity, but had no negative effect on the length-weight relationship (L-W. Data support the conclusion that fingerling stocked at 400 and 500 fish m-3 shows high performance during 9-weeks when the biomass not exceed 37 kg m-3. At this time fish have reached the desired final nursery weight (50 g for transfer to grow-out facilities.

  8. 臭氧处理技术在工厂化水产养殖中的应用研究%Application of Ozone in Recirculating Aquaculture System

    Institute of Scientific and Technical Information of China (English)

    周煊亦; 房燕; 曹广斌; 蒋树义; 韩世成; 陈忠祥; 郭常有

    2012-01-01

    臭氧消毒是工厂化水产养殖中水处理的关键技术之一。本文详细介绍了臭氧的物理、化学性质,论述了臭氧制造、水中溶解及水中溶解浓度的检测方法。结合国内外有关水产养殖水处理技术的研究成果与发展趋势,分析了臭氧在工厂化水产养殖水处理中的一些作用和应用特性。介绍了臭氧在工厂化水产养殖中消毒杀菌、氧化有机物、凝聚悬浮物、除臭与除色方面的作用,阐明了臭氧在工厂化水产养殖中的应用前景。%Ozone disinfection of water is one kind of key technology in water treatment of recirculating aquaculture system.This paper describes the physical and chemical nature of ozone and several ways of manufacturing,dissolving and detection of ozone.Based on aquaculture water treatment technology research and development trends,some of the role and the application feature that ozone used in aquaculture water treatment factory are analyzed.In recirculating aquaculture,ozone can be used in disinfection and sterilization,oxidation of organic compounds,suspended solids cohesion,deodorization and decolourization.Meanwhile,the application prospect of ozone was discussed.

  9. Reliability of electronic systems

    International Nuclear Information System (INIS)

    Reliability techniques have been developed subsequently as a need of the diverse engineering disciplines, nevertheless they are not few those that think they have been work a lot on reliability before the same word was used in the current context. Military, space and nuclear industries were the first ones that have been involved in this topic, however not only in these environments it is that it has been carried out this small great revolution in benefit of the increase of the reliability figures of the products of those industries, but rather it has extended to the whole industry. The fact of the massive production, characteristic of the current industries, drove four decades ago, to the fall of the reliability of its products, on one hand, because the massively itself and, for other, to the recently discovered and even not stabilized industrial techniques. Industry should be changed according to those two new requirements, creating products of medium complexity and assuring an enough reliability appropriated to production costs and controls. Reliability began to be integral part of the manufactured product. Facing this philosophy, the book describes reliability techniques applied to electronics systems and provides a coherent and rigorous framework for these diverse activities providing a unifying scientific basis for the entire subject. It consists of eight chapters plus a lot of statistical tables and an extensive annotated bibliography. Chapters embrace the following topics: 1- Introduction to Reliability; 2- Basic Mathematical Concepts; 3- Catastrophic Failure Models; 4-Parametric Failure Models; 5- Systems Reliability; 6- Reliability in Design and Project; 7- Reliability Tests; 8- Software Reliability. This book is in Spanish language and has a potentially diverse audience as a text book from academic to industrial courses. (author)

  10. [Analysis of the changes of microbial community structure on bio-carrier of recirculating aquaculture systems (RAS)].

    Science.gov (United States)

    Zhang, Hai-Geng; Ma, Shao-Sai; Li, Qiu-Fen; Fu, Xue-Jun; Zhang, Yan; Qu, Ke-Ming

    2011-01-01

    In order to study the variation of microbial community structure and the mechanism of denitrification on bio-carrier in recirculating aquaculture systems (RAS) during the periods of bio-film formation and operation the systems, traditional microbiological methods were applied to count the quantity of heterotrophic bacteria, ammonia oxidize bacteria and nitrite oxidize bacteria. The amplified products of variable V3 region of bacterial 16S rDNA were separated by using denaturing gradient gel electrophoresis (DGGE). And bacterial community DNA fingerprint was obtained. The sequences retrieved from the DGGE bands were used for homology analysis and construction of phylogenetic tree. It presented a trend that the quantity of the three types of bacteria increased gradually to a top and then fallen slowly to a stable level. The composition of microbial community of bio-carrier was very abundant in all periods, and the Shannon index was 1.53, 1.44, 1.57, 1.08, 1.27 and 1.30, respectively. During different periods, there was a certain shift in the microbial community structure, while the C(s) value (similar index) in two adjacent periods was high, indicating the variation and succession of the microbial community was slow and regular. Several bacteria had an effect on removal of pollutants for farming water and the effluent water quality could meet the requirements of high-density culture. Among them, Proteobacteria and Flavobacteria were main communities. The Nitrosomonas and some other facultative anaerobic bacteria (Flavobacteriaceae bacterium) were identified, which indicated that there may be coexisted pathways of nitrification and denitrification in bio-filter.

  11. Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system.

    Science.gov (United States)

    Pungrasmi, Wiboonluk; Playchoom, Cholticha; Powtongsook, Sorawit

    2013-08-01

    A bottom substrate denitrification tank for a recirculating aquaculture system was developed. The laboratory scale denitrification tank was an 8 L tank (0.04 m2 tank surface area), packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria. An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions (e.g. > 2 mg/L) while anoxic conditions predominated only at the bottom substrate layer. The results showed that, among the four substrates tested (soil, sand, pumice stone and vermiculite), pumice was the most preferable material. Comparing carbon supplementation using methanol and molasses, methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses. When methanol was applied at the optimal COD:N ratio of 5:1, a nitrate removal rate of 4591 +/- 133 mg-N/m2 tank bottom area/day was achieved. Finally, nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system. Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD:N ratio of 5:1. The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia. The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 +/- 945 mg-N/m2 tank bottom area/day or 126 +/- 18 mg-N/L of pumice packing volume/day. PMID:24520693

  12. Uncultured bacterial diversity in a seawater recirculating aquaculture system revealed by 16S rRNA gene amplicon sequencing.

    Science.gov (United States)

    Lee, Da-Eun; Lee, Jinhwan; Kim, Young-Mog; Myeong, Jeong-In; Kim, Kyoung-Ho

    2016-04-01

    Bacterial diversity in a seawater recirculating aquaculture system (RAS) was investigated using 16S rRNA amplicon sequencing to understand the roles of bacterial communities in the system. The RAS was operated at nine different combinations of temperature (15°C, 20°C, and 25°C) and salinity (20‰, 25‰, and 32.5‰). Samples were collected from five or six RAS tanks (biofilters) for each condition. Fifty samples were analyzed. Proteobacteria and Bacteroidetes were most common (sum of both phyla: 67.2% to 99.4%) and were inversely proportional to each other. Bacteria that were present at an average of ≥ 1% included Actinobacteria (2.9%) Planctomycetes (2.0%), Nitrospirae (1.5%), and Acidobacteria (1.0%); they were preferentially present in packed bed biofilters, mesh biofilters, and maturation biofilters. The three biofilters showed higher diversity than other RAS tanks (aerated biofilters, floating bed biofilters, and fish tanks) from phylum to operational taxonomic unit (OTU) level. Samples were clustered into several groups based on the bacterial communities. Major taxonomic groups related to family Rhodobacteraceae and Flavobacteriaceae were distributed widely in the samples. Several taxonomic groups like [Saprospiraceae], Cytophagaceae, Octadecabacter, and Marivita showed a cluster-oriented distribution. Phaeobacter and Sediminicola-related reads were detected frequently and abundantly at low temperature. Nitrifying bacteria were detected frequently and abundantly in the three biofilters. Phylogenetic analysis of the nitrifying bacteria showed several similar OTUs were observed widely through the biofilters. The diverse bacterial communities and the minor taxonomic groups, except for Proteobacteria and Bacteroidetes, seemed to play important roles and seemed necessary for nitrifying activity in the RAS, especially in packed bed biofilters, mesh biofilters, and maturation biofilters.

  13. Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    Wiboonluk Pungrasmi; Cholticha Playchoom; Sorawit Powtongsook

    2013-01-01

    A bottom substrate denitrification tank for a recirculating aquaculture system was developed.The laboratory scale denitrification tank was an 8 L tank (0.04 m2 tank surface area),packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria.An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions (e.g.> 2 mg/L) while anoxic conditions predominated only at the bottom substrate layer.The results showed that,among the four substrates tested (soil,sand,pumice stone and vermiculite),pumice was the most preferable material.Comparing carbon supplementation using methanol and molasses,methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses.When methanol was applied at the optimal COD∶N ratio of 5∶1,a nitrate removal rate of 4591 ± 133 mg-N/m2 tank bottom area/day was achieved.Finally,nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system.Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD∶N ratio of 5∶1.The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia.The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 ± 945 mg-N/m2 tank bottom area/day or 126 ± 18 mg-N/L of pumice packing volume/day.

  14. Uncultured bacterial diversity in a seawater recirculating aquaculture system revealed by 16S rRNA gene amplicon sequencing.

    Science.gov (United States)

    Lee, Da-Eun; Lee, Jinhwan; Kim, Young-Mog; Myeong, Jeong-In; Kim, Kyoung-Ho

    2016-04-01

    Bacterial diversity in a seawater recirculating aquaculture system (RAS) was investigated using 16S rRNA amplicon sequencing to understand the roles of bacterial communities in the system. The RAS was operated at nine different combinations of temperature (15°C, 20°C, and 25°C) and salinity (20‰, 25‰, and 32.5‰). Samples were collected from five or six RAS tanks (biofilters) for each condition. Fifty samples were analyzed. Proteobacteria and Bacteroidetes were most common (sum of both phyla: 67.2% to 99.4%) and were inversely proportional to each other. Bacteria that were present at an average of ≥ 1% included Actinobacteria (2.9%) Planctomycetes (2.0%), Nitrospirae (1.5%), and Acidobacteria (1.0%); they were preferentially present in packed bed biofilters, mesh biofilters, and maturation biofilters. The three biofilters showed higher diversity than other RAS tanks (aerated biofilters, floating bed biofilters, and fish tanks) from phylum to operational taxonomic unit (OTU) level. Samples were clustered into several groups based on the bacterial communities. Major taxonomic groups related to family Rhodobacteraceae and Flavobacteriaceae were distributed widely in the samples. Several taxonomic groups like [Saprospiraceae], Cytophagaceae, Octadecabacter, and Marivita showed a cluster-oriented distribution. Phaeobacter and Sediminicola-related reads were detected frequently and abundantly at low temperature. Nitrifying bacteria were detected frequently and abundantly in the three biofilters. Phylogenetic analysis of the nitrifying bacteria showed several similar OTUs were observed widely through the biofilters. The diverse bacterial communities and the minor taxonomic groups, except for Proteobacteria and Bacteroidetes, seemed to play important roles and seemed necessary for nitrifying activity in the RAS, especially in packed bed biofilters, mesh biofilters, and maturation biofilters. PMID:27033205

  15. Use of Probiotics in Aquaculture

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Diseases of cultured animal and environmental pollution are very important problems in aquaculture.The use of probiotics in aquaculture has more adva ntages than the use of antibiotics and chemicals in aquaculture. This review int roduces the use and mechanisms of the probiotics in aquaculture.

  16. Water and nutrient budgets of ponds in integrated agriculture-aquaculture systems in the Mekong Delta, Vietnam.

    NARCIS (Netherlands)

    Nhan, D.K.; Verdegem, M.C.J.; Milstein, A.; Verreth, J.A.J.

    2008-01-01

    A participatory on-farm study analysed water and nutrient budgets of six low and four high water-exchange ponds of integrated agriculture-aquaculture (IAA) farms in the Mekong delta. Water, nitrogen (N), organic carbon (OC) and phosphorus (P) flows through the ponds were monitored, and data on fish

  17. The influence of fishmeal-free diets on microbial communities in Atlantic salmon Salmo salar recirculation aquaculture systems

    Science.gov (United States)

    The reliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and promoting price instability. Advances in alternative diet for...

  18. 淡水养殖池塘水质评价指标体系研究%Water Quality Evaluation Index System for Freshwater Aquaculture Pond

    Institute of Scientific and Technical Information of China (English)

    刘曼红; 于洪贤; 刘其根; 王瑞梅

    2011-01-01

    [目的]建立淡水养殖池塘水质评价指标体系。[方法]通过专家访谈法、问卷调查法、实地调研法及DELPHI法,在综合分析淡水养殖池塘水质各影响因子的基础上,对14个淡水养殖池塘水环境因子的重要程度进行了排序,选择其中5个因素作为指标建立了淡水养殖池塘水质评价指标体系,并确定了各指标的阈值。[结果]淡水养殖池塘水质因子重要程度排序为溶解氧〉pH〉浮游植物量〉透明度〉总氮〉浮游动物量〉水温〉生化需氧量〉水色〉盐度〉总硬度;根据重要程度的大小,确定溶解氧、pH、透明度、浮游植物量、总氮5个指标为池塘水质评价的指标体%[Objective] The aim was to establish the water quality evaluation index system for freshwater aquaculture pond.[Method] The expert survey,DELPHI,field research and other methods were used.Based on the analysis of factors influencing water quality of freshwater aquaculture pond,and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered.Then,five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination for thresholds of these factors.[Result] The importance degree of water quality of freshwater aquaculture pond showed an order of Dissolved oxygenpHPhytoplankton biomassSecchi depthTotal NitrogenZooplankton biomassWater temperatureBiochemical Oxygen DemandWater colorSalinityTotal hardness;according to the value of importance degree,the dissolved oxygen,pH,secchi depth,phytoplankton biomass and total nitrogen these five factors were selected as the index system of water quality evaluation of pond.The level of water quality of freshwater aquaculture pond was divided into five,and the tolerance range of fish to each index was obtained by expert observation.[Conclusion] This study had provided a scientific basis for water quality evaluation system

  19. Modelling studies of fish production in integrated agriculture-aquaculture systems.

    NARCIS (Netherlands)

    Dam, van A.A.

    1995-01-01

    The general objective of this thesis is to formulate a general model for fish production in integrated ponds and ricefields as a means of obtaining a better understanding of these production systems. Integrated culture systems produce fish without large industrial energy inputs and have positive eff

  20. Association of mycobacteria in recirculating aquaculture systems and mycobacterial disease in fish.

    Science.gov (United States)

    Yanong, Roy P E; Pouder, Deborah B; Falkinham, Joseph O

    2010-12-01

    Mycobacterium marinum isolates cultivated from tissue containing granulomatous lesions in Florida pompano Trachinotus carolinus and from biofilm samples collected from their tank and water recirculating system had identical (L1 of 11 bands) repetitive-sequence-based polymerase chain reaction (rep-PCR) DNA fingerprints. A second M. marinum clone sharing 4 of 11 rep-PCR bands with the first clone was isolated from some fish tissues but not from system samples. Water samples yielded low numbers of colonies of mycobacteria (0.08-1.3/mL), but high numbers were recovered from biofilms (260-12,000/swab) and filters (63-21,000/ filter). Mycobacterium hemophilum, M. chelonae, M. trivale, M. gastri, and M. gordonae were isolated from system samples alone. PMID:21413504

  1. [Electronic poison information management system].

    Science.gov (United States)

    Kabata, Piotr; Waldman, Wojciech; Kaletha, Krystian; Sein Anand, Jacek

    2013-01-01

    We describe deployment of electronic toxicological information database in poison control center of Pomeranian Center of Toxicology. System was based on Google Apps technology, by Google Inc., using electronic, web-based forms and data tables. During first 6 months from system deployment, we used it to archive 1471 poisoning cases, prepare monthly poisoning reports and facilitate statistical analysis of data. Electronic database usage made Poison Center work much easier. PMID:24466697

  2. [Electronic poison information management system].

    Science.gov (United States)

    Kabata, Piotr; Waldman, Wojciech; Kaletha, Krystian; Sein Anand, Jacek

    2013-01-01

    We describe deployment of electronic toxicological information database in poison control center of Pomeranian Center of Toxicology. System was based on Google Apps technology, by Google Inc., using electronic, web-based forms and data tables. During first 6 months from system deployment, we used it to archive 1471 poisoning cases, prepare monthly poisoning reports and facilitate statistical analysis of data. Electronic database usage made Poison Center work much easier.

  3. Performance of an in-situ rotating biological contactor in a recirculating aquaculture system.

    Science.gov (United States)

    Marin, P; Donoso-Bravo, A; Campos, J L; Ruiz-Filippi, G; Chamy, R

    2011-01-01

    The start-up and activation of a nitrifying rotating biological contactor (RBC) and its performance inside a culture tank of rainbow trout were studied. First, in a lab-scale operation, the system was fed with a synthetic medium containing a high ammonia concentration (567 mg NH(4)(+)-N L(-1)) and operated at a high hydraulic retention time (HRT) (6.5 days) to minimize the wash-out of the biomass and promote the biofilm formation. Then, both inlet ammonia concentration and HRT were decreased in order to obtain operational conditions similar to those of the culture tank. During this period, the RBC was able to treat an ammonia loading rate (ALR) of 0.64 g N-NH(4)(+) L(-1) d(-1) with a removal efficiency within 70-100%. Pilot-scale experiments were carried out in culture tanks of rainbow trout. The operation of a recirculating system with the RBC unit was compared with a recirculating system without biological treatment and with a flow-through system. The use of this in-situ nitrifying unit allowed working at a recirculation ratio of 90% without negative effects on either growth or the condition factor of fishes. Up to 70% of ammonia generated was removed and a removal rate of 1.41 g NH(4)(+)-N m(-2) d(-1) was reached. PMID:22156125

  4. Capacity building improve Malaysia's inspection and monitoring system for aquaculture and fishery products

    NARCIS (Netherlands)

    Gevers, G.J.M.; Zoontjes, P.W.; Essers, M.L.; Klijnstra, M.; Gerssen, A.

    2012-01-01

    The project aimed to help build a credible inspection and monitoring system that can guarantee safe quality products of Ministry of Health (MoH) and Department of Fisheries (DoF) by upgrading the analytical capacity of the laboratory staff directly involved in the analysis and detection of forbidden

  5. Microalgae for aquaculture

    OpenAIRE

    Michels, M.H.A.

    2015-01-01

    In 2007, the project ‘Zeeuwse Tong’ (Zeeland Sole) was founded with support of the province of Zeeland, the Netherlands. The aim of the Zeeuwse Tong project was to establish an innovative land-based integrated multi-trophic aquaculture sector, which is producing sole, ragworms, algae, shellfish and saline crops in close harmony with nature. The project was divided into two sub-projects: The integrated saline aquaculture farm and the integrated nursery. The research described in this thesis re...

  6. Zebrafish as animal model for aquaculture nutrition research

    OpenAIRE

    Ulloa, Pilar E.; Medrano, Juan F.; Feijoo, Carmen G.

    2014-01-01

    The aquaculture industry continues to promote the diversification of ingredients used in aquafeed in order to achieve a more sustainable aquaculture production system. The evaluation of large numbers of diets in aquaculture species is costly and requires time-consuming trials in some species. In contrast, zebrafish (Danio rerio) can solve these drawbacks as an experimental model, and represents an ideal organism to carry out preliminary evaluation of diets. In addition, zebrafish has a sequen...

  7. Electronic Resource Management Systems

    Directory of Open Access Journals (Sweden)

    Mark Ellingsen

    2004-10-01

    Full Text Available Computer applications which deal with electronic resource management (ERM are quite a recent development. They have grown out of the need to manage the burgeoning number of electronic resources particularly electronic journals. Typically, in the early years of e-journal acquisition, library staff provided an easy means of accessing these journals by providing an alphabetical list on a web page. Some went as far as categorising the e-journals by subject and then grouping the journals either on a single web page or by using multiple pages. It didn't take long before it was recognised that it would be more efficient to dynamically generate the pages from a database rather than to continually edit the pages manually. Of course, once the descriptive metadata for an electronic journal was held within a database the next logical step was to provide administrative forms whereby that metadata could be manipulated. This in turn led to demands for incorporating more information and more functionality into the developing application.

  8. Preliminary research on the anammox process and control of nitrogen compounds in a recirculating aquaculture system

    OpenAIRE

    Savin Cristian; Păsărin Benone; Patriche Neculai; Talpeş Marilena; Cristea Victor; Tenciu Magdalena

    2013-01-01

    Using anammox process in biological filtration of technological water within recirculatingaquaculture system is an alternative to nitrification / denitrification process which can reduce productioncosts, especially energy by replacing aerobic biological processes that require high oxygen consumption,provided through the addition for optimal function of biofilter (conversion of N-NH4 and N-NO2). Aim ofthis paper is to highlight the first steps in the control of nitrogen compounds in recirculat...

  9. 2-Methylisoborneol and geosmin uptake by organic sludge derived from a recirculating aquaculture system.

    Science.gov (United States)

    Guttman, Lior; van Rijn, Jaap

    2009-02-01

    In a previous study on a recirculating fish culture system, levels of geosmin and 2-methylisoborneol were found to decrease when culture water was recirculated through the anaerobic sludge digestion treatment stage of the system. This finding led us to the present study in which the geosmin and 2-methylisoborneol removal capacity of the sludge derived from this treatment stage was examined in vitro. It was found that reduction of off-flavor compounds by the sludge was mediated by both chemical/physical sorption and biological degradation. At geosmin and 2-methylisoborneol concentrations within the range of those experienced in fish culture systems, chemical/physical sorption by the sludge was found to account for a 93% reduction in geosmin and a 79% reduction in 2-methylisoborneol from the overlying water within 48h of incubation. Combined with the biological degradation taking place in the sludge, a complete removal of these compounds from the water phase occurred within 9 days of incubation. By means of repeated washing of the geosmin and 2-methylisoborneol contaminate sludge with clean water, relatively small amounts of these compounds were released from the sludge, a possible indication for the fact that absorption, rather than adsorption, underlies the chemical/physical removal process. PMID:18986667

  10. Fuzzy logic based control system for fresh water aquaculture: A MATLAB based simulation approach

    Directory of Open Access Journals (Sweden)

    Rana Dinesh Singh

    2015-01-01

    Full Text Available Fuzzy control is regarded as the most widely used application of fuzzy logic. Fuzzy logic is an innovative technology to design solutions for multiparameter and non-linear control problems. One of the greatest advantages of fuzzy control is that it uses human experience and process information obtained from operator rather than a mathematical model for the definition of a control strategy. As a result, it often delivers solutions faster than conventional control design techniques. The proposed system is an attempt to apply fuzzy logic techniques to predict the stress factor on the fish, based on line data and rule base generated using domain expert. The proposed work includes a use of Data acquisition system, an interfacing device for on line parameter acquisition and analysis, fuzzy logic controller (FLC for inferring the stress factor. The system takes stress parameters on the fish as inputs, fuzzified by using FLC with knowledge base rules and finally provides single output. All the parameters are controlled and calibrated by the fuzzy logic toolbox and MATLAB programming.

  11. 2-Methylisoborneol and geosmin uptake by organic sludge derived from a recirculating aquaculture system.

    Science.gov (United States)

    Guttman, Lior; van Rijn, Jaap

    2009-02-01

    In a previous study on a recirculating fish culture system, levels of geosmin and 2-methylisoborneol were found to decrease when culture water was recirculated through the anaerobic sludge digestion treatment stage of the system. This finding led us to the present study in which the geosmin and 2-methylisoborneol removal capacity of the sludge derived from this treatment stage was examined in vitro. It was found that reduction of off-flavor compounds by the sludge was mediated by both chemical/physical sorption and biological degradation. At geosmin and 2-methylisoborneol concentrations within the range of those experienced in fish culture systems, chemical/physical sorption by the sludge was found to account for a 93% reduction in geosmin and a 79% reduction in 2-methylisoborneol from the overlying water within 48h of incubation. Combined with the biological degradation taking place in the sludge, a complete removal of these compounds from the water phase occurred within 9 days of incubation. By means of repeated washing of the geosmin and 2-methylisoborneol contaminate sludge with clean water, relatively small amounts of these compounds were released from the sludge, a possible indication for the fact that absorption, rather than adsorption, underlies the chemical/physical removal process.

  12. 基于PLC循环水养殖温控系统的设计%The Design of Recirculating Aquaculture Temperature Control System Based on PLC

    Institute of Scientific and Technical Information of China (English)

    吴燕翔; 胡咏梅; 刘雨青

    2011-01-01

    针对目前国内水产养殖监控系统较落后的研究现状,设计了采用西门子S7-200PLC的循环水养殖温控系统,采用PID控制算法,对养殖池的水位和温度进行实时监控,实现养殖池温度和水位的恒定控制.详细介绍了系统的整体控制方案,工作原理,并给出了系统的软、硬件结构设计,有效地实现了系统的逻辑控制、安全控制、故障显示及故障处理.%Since study on the domestic aquaculture monitoring system was backward at present, the SIMATIC S7-200 CPU226 is used and adopted PID control algorithm to make real-time monitoring and controlling for the water level and temperature of closed circulating aquaculture system, thus it realized constant water level and temperature control in the culture pond. The system overall control scheme and principle are introduced in detail, and the system software and hardware structure design are given, the system has efficiently implemented system logic control, safetv control, fault display and fault treatment.

  13. 欧洲循环水养殖系统研究进展%Developments of recirculating aquaculture systems in Europe

    Institute of Scientific and Technical Information of China (English)

    丁建乐; 鲍旭腾; 梁澄

    2011-01-01

    The innovation and development of recirculating aquaculture system ( RAS) technology in Europe keeps continuing, with the strengthening of environmental regulations in EU and European countries. This paper introduced and analyzed the development status of European recirculating aquaculture system, such as the application of Life Cycle Assessment (LCA) method for evaluating the environmental impact of RAS, and the increasing species diversity of RAS production, etc. The paper also highlighted the application of denitrifying reaction technology, sludge concentration technology, and ozone treatment technology in RAS. On this basis, the paper pointed out the new challenges with which the recirculating aquaculture system may be faced.%欧洲循环水养殖系统技术随着欧盟和欧洲各国环保法规的加强而不断创新和发展.本文对欧洲正在使用生命周期法对循环水养殖进行环境影响评估的状况,以及欧洲应用独特的循环水养殖系统技术增加了养殖的品种进行了介绍和分析.并着重介绍了欧洲循环水养殖系统新技术的应用及其发展状况,特别阐述了脱硝反应技术、淤泥浓缩技术和臭氧技术等新技术在循环水养殖系统的应用情况.在此基础上,指出了循环水养殖可能面临的新挑战.

  14. Recirculating aquaculture system for high density production of the calanoid copepod Acartia tonsa (Dana)

    DEFF Research Database (Denmark)

    Vu, Minh Thi Thuy; Øie, Gunvor; Reinertsen, Helge

    capacity. A. tonsa fed the unicellular algae Rhodomonas baltica were registered for four weeks in triplicate 50 L tanks in each system. Water quality parameters were recorded daily for temperature, oxygen, pH, salinity, particles and every five days for nitrogenous waste and bacteria through...... species. The RAS also needs a further optimisation of water quality by a denitrifying filter component to stabilize for copepod cultivation and an implementation of disease control treatment is also required.......The calanoid copepod Acartia tonsa (Dana) is one of the most promising copepod species for marine larviculture. This species has a wide tolerance to temperature and salinity, small size, can produce resting eggs. All their nauplii, copepodites and adults can be use as excellent feeds for marine...

  15. Water Quality Evaluation Index System of Freshwater Aquaculture Pond%淡水养殖池塘水质评价指标体系研究

    Institute of Scientific and Technical Information of China (English)

    刘曼红; 于洪贤; 刘其根; 王瑞梅

    2011-01-01

    [Objective] The aim was to establish the water quality evaluation index system of freshwater aquaculture pond. [Method] The ex-pert survey, DELPHI, field research and other methods were used. Based on the analysis of factors influencing water quality of freshwater aq-uaculture pond, and the importance degree of 14 factors influencing water quality of freshwater aquaculture pond was ordered. Then, five factors were selected as index to establish the water quality evaluation index system of freshwater aquaculture with the determination of thresholds of these factors. [ Result] The importance degree of water quality of freshwater aquacultuie pond showed an order of disslved oxygen > pH > phytoplankton quantity > transparency > total Nitrogen > zooplankton quantity > water temperature > biochemical oxygen demand > water color > salinity > total hardness; according to the value of importance degree, the dissolved oxygen, pH, transparency, phytoplankton quantity and total nitrogen these five factors were selected as the index system of water quality evaluation of pond. The level of water quality of freshwater aquaculture pond was divided into five, and the tolerance range of fish to each index was obtained by expert observation. [Conclusion ] This study had provided a scientific basis for water quality evaluation system of freshwater aquaculture pond.%[目的]建立淡水养殖池塘水质评价指标体系.[方法]通过专家访谈法、问卷调查法、实地调研法及DELPHI法,在综合分析淡水养殖池塘水质各影响因子的基础上,对14个淡水养殖池塘水环境因子的重要程度进行了排序,选择其中5个因素作为指标建立了淡水养殖池塘水质评价指标体系,并确定了各指标的阈值.[结果]淡水养殖池塘水质因子重要程度排序为溶解氧>pH>浮游植物量>透明度>总氮>浮游动物量>水温>生化需氧量>水色>盐度>总硬度;根据重要程度的天小,

  16. Results regarding growth performance of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758) fed with an additive feed, vitamin C, in a recirculating aquaculture system.

    OpenAIRE

    Catalina Ciortan Mirea

    2013-01-01

    The aim of this study was to determine the vitamin C status on growth performance, survival rate and biochimical parameters from tissue of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758) with average weight of 93±1,0 g were fed with different dietary vitamin C rations and reared in a recirculating aquaculture system (RAS). Growth performance , survival rate and biochimical parameters from tissue of Nile tilapia were measured in groups fed diets supplemented with 100, 750, 2000 mg.kg-1L-a...

  17. Preliminary research on the anammox process and control of nitrogen compounds in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Savin Cristian

    2013-01-01

    Full Text Available Using anammox process in biological filtration of technological water within recirculatingaquaculture system is an alternative to nitrification / denitrification process which can reduce productioncosts, especially energy by replacing aerobic biological processes that require high oxygen consumption,provided through the addition for optimal function of biofilter (conversion of N-NH4 and N-NO2. Aim ofthis paper is to highlight the first steps in the control of nitrogen compounds in recirculating aquaculturesystems using anammox process. Data shown are obtained after 78 researching days (research stillongoing, the results being encouraging, registering an ammonium removal efficiency of 77% in SC1 andof 32% in SC2. Nitrites registered an increase in SC1 and a decrease in SC2 and there are allprerequisites showing that in SC2 anammox activity is more advanced than in SC1. The average ofoxygen consumption rate was 0.73 mgL-1 in SC1 smaller than 0.99 mgL-1 from SC2, which reinforces theidea that there are anammox process in SC2.

  18. Responsible aquaculture in 2050: Valuing local conditions and human innovations will be key to success

    NARCIS (Netherlands)

    Diana, J.S.; Egna, H.S.; Chopin, T.; Peterson, M.S.; Cao, L.; Pomeroy, R.; Verdegem, M.C.J.; Slack, W.T.; Bondad-Reantaso, M.G.; Cabello, F.

    2013-01-01

    As aquaculture production expands, we must avoid mistakes made during increasing intensification of agriculture. Understanding environmental impacts and measures to mitigate them is important for designing responsible aquaculture production systems. There are four realistic goals that can make futur

  19. Cribrihabitans marinus gen. nov., sp. nov., isolated from a biological filter in a marine recirculating aquaculture system.

    Science.gov (United States)

    Chen, Zhu; Liu, Ying; Liu, Liang-Zi; Zhong, Zhi-Ping; Liu, Zhi-Pei; Liu, Ying

    2014-04-01

    A Gram-negative bacterium, strain CZ-AM5(T), was isolated from an aerated biological filter in a marine recirculating aquaculture system in Tianjin, China. Its taxonomic position was investigated by using a polyphasic approach. Cells of strain CZ-AM5(T) were non-spore-forming rods, 0.5-0.8 µm wide and 1.2-2.0 µm long, and motile by means of one or two polar or lateral flagella. Strain CZ-AM5(T) was strictly aerobic, heterotrophic, oxidase-negative and catalase-positive. Growth occurred at 15-40 °C (optimum, 30-35 °C), at pH 6.5-10.5 (optimum, pH 7.0-7.5) and in the presence of 0-12.0 % (w/v) NaCl (optimum, 4.0 %). The predominant fatty acid was C18 : 1ω7c (80.3 %). Ubiquinone 10 (Q-10) was the sole respiratory quinone. The polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unknown aminolipid, an unknown phospholipid and three unknown lipids. The DNA G+C content was 60.4 mol%. Strain CZ-AM5(T) showed the highest 16S rRNA gene sequence similarity (96.5 %) to Phaeobacter caeruleus LMG 24369(T); it exhibited 16S rRNA gene sequence similarity of 95.0-96.5, 95.2-96.3, 96.2, 94.6-95.7 and 94.8-95.8 % to members of the genera Phaeobacter, Ruegeria, Citreimonas, Leisingera and Donghicola, respectively. However, phylogenetic trees based on 16S rRNA gene sequences showed that strain CZ-AM5(T) did not join any of the above genera, but formed a distinct lineage in the trees. On the basis of phenotypic, chemotaxonomic and phylogenetic analyses, strain CZ-AM5(T) is considered to represent a novel genus and species of the family Rhodobacteraceae, for which the name Cribrihabitans marinus gen. nov., sp. nov. is proposed. The type strain of Cribrihabitans marinus is CZ-AM5(T) ( = CGMCC 1.13219(T) = JCM 19401(T)). PMID:24425741

  20. A Portable Electron Radiography System

    CERN Document Server

    Merrill, Frank E; Harmon, Frank; Hunt, Alan W; King, B J; Morris, Christopher

    2005-01-01

    The technique of charged particle radiography has been developed and proven with 800 MeV protons at LANSCE and 24 GeV protons at the AGS. Recent work at Los Alamos National Laboratory in collaboration with the Idaho Accelerator Center has extended this diagnostic technique to electron radiography through the development of an inexpensive and portable electron radiography system. This system has been designed to use 30 MeV electrons to radiograph thin static and dynamic systems. The system consists of a compact 30 MeV pulsed electron linear accelerator coupled to a quadrupole lens magnifier constructed from permanent magnet quadrupoles. The design features and operational characteristics of this radiography system are presented as well as the radiographic performance parameters.

  1. 封闭循环水养殖中曝气系统设计及曝气器的选择%Aeration system design and aeration devices selection in Recirculating Aquaculture System

    Institute of Scientific and Technical Information of China (English)

    宋奔奔; 吴凡; 倪琦; 张宇雷; 庄保陆

    2011-01-01

    随着水产养殖业逐渐向高密度、集约化方向的发展,对养殖水体溶解氧浓度的要求越来越高.目前对循环水高密度养殖水体中溶解氧收支平衡的基础研究较少.如何提高氧气的溶解效率、减少氧气的逸出、合理控制溶解氧水平等技术难关的突破,对循环水养殖技术的提高具有重大的意义.本文旨在通过阐述曝气技术的设计理论基础以及曝气设备的最近发展状况,比较各式曝气器的性能参数,从而为封闭循环水养殖曝气系统的设计和曝气器的选择提供理论支持,推动封闭式循环水养殖向精准化的环保节能方向发展.%Dissolved oxygen in water body plays an important role in recirculating aquaculture while developing to higher density and intensification. At present, it' s studied not so much about dissolved oxygen budget and mass balance in intensive recirculating aquaculture system. These problems such as how to improve oxygen dissolving efficiency, decrease oxygen loss and control dissolved oxygen in appropriate level are growing more prominent in recirculating aquaculture system technology. Aeration theory and designing principles, aeration devices characteristics are illustrated and elaborated in this paper to improve the design of recirculating aquaculture aeration system and the selecting of aeration devices, promoting recirculating aquaculture system technology to more environment-friendly and energy conservation.

  2. Discussion on the precision of energy conserving industrialized recirculation aquaculture system%论节能型工厂化循环水养殖的精准化

    Institute of Scientific and Technical Information of China (English)

    黄滨; 高淳仁; 关长涛; 梁友; 崔勇; 李娇

    2011-01-01

    渔业实施精准化战略,是我国现代渔业向工业化发展的必由之路.工厂化循环水养殖作为一种环境友好型和资源节约型先进养殖模式的典范,实施精准化是推动水产养殖产业向工业化迈进的加速器和重要标志,有积极的示范作用.本文论节能型工厂化循环水养殖的精准化,从养殖技术与设施装备,以及集成的各个环节和不同角度进行了可精准化的分析,对其实现途径作了较全面的阐述.%Precision fisheries strategy is a necessary pathway for the industrialization of modern fisheries in China. The land - based industrialized recirculation aquaculture system is an example of advanced environment - friendly and resource - conserving cultivation mode. Implementation of precision approach is an accelerator and indicator for aquaculture industrialization, which may act as a positive paradigm. Precision of energy conserving industrialized recirculation aquaculture is discussed in this paper, with analysis of various aspects including the cultivation technologies and facilities, as well as each integrated step and different elements in cultivation that could be improved in precision management, and with detailed illustration on the way to its realization.

  3. Vessel Electronic Reporting System (VERS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The VERS system is composed of a database and other related applications which facilitate the reporting of electronically collected research data via Fisheries...

  4. Aquaculture report 1976

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D.K.; Watson, L.; Kent, J.C.; Johnson, D.W.

    1977-04-08

    Growth of channel catfish (Ictalurus punctatus) and Tilapia zillii in the Reft River Geothermal Area (RRGT) geothermal waters can equal or surpass that in a commercial aquaculture facility. Fish and prawn mortality over the course of the intermediate term preliminary study did not appear to be related to any inherent geothermal water chemistry conditions. Temperature control was a problem but does not appear to be beyond design control. The absence of temperature-related mortality in channel catfish, Tilapia zilli, and yellow perch (Perca flavescens) indicates increased survival and suggests reduced expenditures for disease control. It may also allow higher fish densities in commercial aquaculture operations using geothermal water. Results of this study indicate potential for commercial aquaculture development at the Raft River Geothermal Testing Site.

  5. Contact zoonosis related to aquaculture: a growing concern

    Science.gov (United States)

    Aquaculture develops fast worldwide, with new cultured species and increased global transport of live aquaculture products. There is a growing recognition of zoonotic disease agents causing epidemics and carrier states in cultured fish and shellfish, especially from warm water systems, transmitted t...

  6. Nutrients valorisation via Duckweed-based wastewater treatment and aquaculture

    NARCIS (Netherlands)

    Mohamed El-Shafai, S.A.A.

    2004-01-01

    Development of a sustainable wastewater treatment scheme to recycle sewage nutrients and water in tilapia aquaculture was the main objective of this PhD research. Use of an Integrated UASB-duckweed ponds system for domestic wastewater treatment linked to tilapia aquaculture was investigated. The tr

  7. Certify Sustainable Aquaculture?

    DEFF Research Database (Denmark)

    Bush, Simon; Belton, Ben; Hall, Derek;

    2013-01-01

    Aquaculture, the farming of aquatic organisms, provides close to 50% of the world's supply of seafood, with a value of U.S. $125 billion. It makes up 13% of the world's animal-source protein (excluding eggs and dairy) and employs an estimated 24 million people (1). With capture (i.e., wild......) fisheries production stagnating, aquaculture may help close the forecast global deficit in fish protein by 2020 (2). This so-called “blue revolution” requires addressing a range of environmental and social problems, including water pollution, degradation of ecosystems, and violation of labor standards....

  8. Electron microscopy of pharmaceutical systems.

    Science.gov (United States)

    Klang, Victoria; Valenta, Claudia; Matsko, Nadejda B

    2013-01-01

    During the last decades, the focus of research in pharmaceutical technology has steadily shifted towards the development and optimisation of nano-scale drug delivery systems. As a result, electron microscopic methods are increasingly employed for the characterisation of pharmaceutical systems such as nanoparticles and microparticles, nanoemulsions, microemulsions, solid lipid nanoparticles, different types of vesicles, nanofibres and many more. Knowledge of the basic properties of these systems is essential for an adequate microscopic analysis. Classical transmission and scanning electron microscopic techniques frequently have to be adapted for an accurate analysis of formulation morphology, especially in case of hydrated colloidal systems. Specific techniques such as environmental scanning microscopy or cryo preparation are required for their investigation. Analytical electron microscopic techniques such as electron energy-loss spectroscopy or energy-dispersive X-ray spectroscopy are additional assets to determine the elemental composition of the systems, but are not yet standard tools in pharmaceutical research. This review provides an overview of pharmaceutical systems of interest in current research and strategies for their successful electron microscopic analysis. Advantages and limitations of the different methodological approaches are discussed and recent findings of interest are presented. PMID:22921788

  9. Component reliability for electronic systems

    CERN Document Server

    Bajenescu, Titu-Marius I

    2010-01-01

    The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

  10. Microalgae for aquaculture

    NARCIS (Netherlands)

    Michels, M.H.A.

    2015-01-01

    In 2007, the project ‘Zeeuwse Tong’ (Zeeland Sole) was founded with support of the province of Zeeland, the Netherlands. The aim of the Zeeuwse Tong project was to establish an innovative land-based integrated multi-trophic aquaculture sector, which is producing sole, ragworms, algae, shellfish and

  11. Safety in Aquaculture

    Science.gov (United States)

    Durborow, Robert M.; Myers, Melvin L.

    2016-01-01

    In this article, occupational safety interventions for agriculture-related jobs, specifically in aquaculture, are reviewed. Maintaining quality of life and avoiding economic loss are two areas in which aquaculturists can benefit by incorporating safety protocols and interventions on their farms. The information in this article is based on farm…

  12. Realization of dynamical electronic systems

    Science.gov (United States)

    Hammari, Elena; Catthoor, Francky; Iasemidis, Leonidas; Kjeldsberg, Per Gunnar; Huisken, Jos; Tsakalis, Konstantinos

    2014-04-01

    This article gives an overview of a methodology for building dynamical electronic systems. As an example a part of a system for epileptic seizure prediction is used, which monitors EEG signals and continuously calculates the largest short-term Lyapunov exponents. In dynamical electronic systems, the cost of exploitation, for instance energy consumption, may vary substantially with the values of input signals. In addition, the functions describing the variations are not known at the time the system is designed. As a result, the architecture of the system must accommodate for the worst case exploitation costs, which rapidly exceed the available resources (for instance battery life) when accumulated over time. The presented system scenario methodology solves these challenges by identifying at design time groups of possible exploitation costs, called system scenarios, and implementing a mechanism to detect system scenarios at run time and re-configure the system to cost-efficiently accommodate them. During reconfiguration, the optimized system architecture settings for the active system scenario are selected and the total exploitation cost is reduced. When the dynamic behavior is due to input data variables with a large number of possible values, current techniques for bottom-up scenario identification and detection becomes too complex. A new top-down technique, based on polygonal regions, is presented in this paper. The results for the example system indicate that with 10 system scenarios the average energy consumption of the system can be reduced by 28% and brought within 5% of the theoretically best solution.

  13. Realization of dynamical electronic systems

    Directory of Open Access Journals (Sweden)

    Hammari Elena

    2014-04-01

    Full Text Available This article gives an overview of a methodology for building dynamical electronic systems. As an example a part of a system for epileptic seizure prediction is used, which monitors EEG signals and continuously calculates the largest short-term Lyapunov exponents. In dynamical electronic systems, the cost of exploitation, for instance energy consumption, may vary substantially with the values of input signals. In addition, the functions describing the variations are not known at the time the system is designed. As a result, the architecture of the system must accommodate for the worst case exploitation costs, which rapidly exceed the available resources (for instance battery life when accumulated over time. The presented system scenario methodology solves these challenges by identifying at design time groups of possible exploitation costs, called system scenarios, and implementing a mechanism to detect system scenarios at run time and re-configure the system to cost-efficiently accommodate them. During reconfiguration, the optimized system architecture settings for the active system scenario are selected and the total exploitation cost is reduced. When the dynamic behavior is due to input data variables with a large number of possible values, current techniques for bottom-up scenario identification and detection becomes too complex. A new top-down technique, based on polygonal regions, is presented in this paper. The results for the example system indicate that with 10 system scenarios the average energy consumption of the system can be reduced by 28% and brought within 5% of the theoretically best solution.

  14. Genomic approaches in aquaculture and fisheries

    DEFF Research Database (Denmark)

    Cancela, M. Leonor; Bargelloni, Luca; Boudry, Pierre;

    2010-01-01

    Despite the enormous input into the worldwide development of fish and shellfish farming in the recent decades, in part as an attempt to minimize the impact of fishing on already overexploited natural populations, the application of genomics to aquaculture and fisheries remains poorly developed....... Improving state-of-the-art genomics research in various aquaculture systems, as well as its industrial applications, remains one of the major challenges in this area and should be the focus of well developed strategies to be implemented in the next generation of projects. This chapter will first provide...

  15. Molecular analysis of bacterial communities and detection of potential pathogens in a recirculating aquaculture system for Scophthalmus maximus and Solea senegalensis.

    Directory of Open Access Journals (Sweden)

    Patrícia Martins

    Full Text Available The present study combined a DGGE and barcoded 16S rRNA pyrosequencing approach to assess bacterial composition in the water of a recirculating aquaculture system (RAS with a shallow raceway system (SRS for turbot (Scophthalmus maximus and sole (Solea senegalensis. Barcoded pyrosequencing results were also used to determine the potential pathogen load in the RAS studied. Samples were collected from the water supply pipeline (Sup, fish production tanks (Pro, sedimentation filter (Sed, biofilter tank (Bio, and protein skimmer (Ozo; also used as an ozone reaction chamber of twin RAS operating in parallel (one for each fish species. Our results revealed pronounced differences in bacterial community composition between turbot and sole RAS, suggesting that in the systems studied there is a strong species-specific effect on water bacterial communities. Proteobacteria was the most abundant phylum in the water supply and all RAS compartments. Other important taxonomic groups included the phylum Bacteriodetes. The saltwater supplied displayed a markedly lower richness and appeared to have very little influence on bacterial composition. The following potentially pathogenic species were detected: Photobacterium damselae in turbot (all compartments, Tenacibaculum discolor in turbot and sole (all compartments, Tenacibaculum soleae in turbot (all compartments and sole (Pro, Sed and Bio, and Serratia marcescens in turbot (Sup, Sed, Bio and Ozo and sole (only Sed RAS. Despite the presence of these pathogens, no symptomatic fish were observed. Although we were able to identify potential pathogens, this approach should be employed with caution when monitoring aquaculture systems, as the required phylogenetic resolution for reliable identification of pathogens may not always be possible to achieve when employing 16S rRNA gene fragments.

  16. Molecular analysis of bacterial communities and detection of potential pathogens in a recirculating aquaculture system for Scophthalmus maximus and Solea senegalensis.

    Science.gov (United States)

    Martins, Patrícia; Cleary, Daniel F R; Pires, Ana C C; Rodrigues, Ana Maria; Quintino, Victor; Calado, Ricardo; Gomes, Newton C M

    2013-01-01

    The present study combined a DGGE and barcoded 16S rRNA pyrosequencing approach to assess bacterial composition in the water of a recirculating aquaculture system (RAS) with a shallow raceway system (SRS) for turbot (Scophthalmus maximus) and sole (Solea senegalensis). Barcoded pyrosequencing results were also used to determine the potential pathogen load in the RAS studied. Samples were collected from the water supply pipeline (Sup), fish production tanks (Pro), sedimentation filter (Sed), biofilter tank (Bio), and protein skimmer (Ozo; also used as an ozone reaction chamber) of twin RAS operating in parallel (one for each fish species). Our results revealed pronounced differences in bacterial community composition between turbot and sole RAS, suggesting that in the systems studied there is a strong species-specific effect on water bacterial communities. Proteobacteria was the most abundant phylum in the water supply and all RAS compartments. Other important taxonomic groups included the phylum Bacteriodetes. The saltwater supplied displayed a markedly lower richness and appeared to have very little influence on bacterial composition. The following potentially pathogenic species were detected: Photobacterium damselae in turbot (all compartments), Tenacibaculum discolor in turbot and sole (all compartments), Tenacibaculum soleae in turbot (all compartments) and sole (Pro, Sed and Bio), and Serratia marcescens in turbot (Sup, Sed, Bio and Ozo) and sole (only Sed) RAS. Despite the presence of these pathogens, no symptomatic fish were observed. Although we were able to identify potential pathogens, this approach should be employed with caution when monitoring aquaculture systems, as the required phylogenetic resolution for reliable identification of pathogens may not always be possible to achieve when employing 16S rRNA gene fragments. PMID:24278329

  17. FTU bolometer electronic system upgrade

    International Nuclear Information System (INIS)

    Highlights: ► Design and realization of a new bolometer electronic system. ► Many improvements over the actual commercial system. ► Architecture based on digital electronic hardware with minimal analog front end. ► Auto off-set correction, real time visualization features and small system size. ► Test results for the electronic system. -- Abstract: The FTU (Frascati Tokamak Upgrade) requires a bolometer diagnostic in order to measure the total plasma radiation. The current diagnostic architecture is based on a full analog multichannel AC bolometer system, which uses a carrier frequency amplifier with a synchronous demodulation. Taking into account the technological upgrades in the field of electronics, it was decided to realize an upgrade for the bolometric electronic system by using a hybrid analog/digital implementation. The new system developed at the ENEA Frascati laboratories has many improvements, and mainly a massive system volume reduction, a good measurement linearity and a simplified use. The new hardware system consists of two subsystems: the Bolometer Digital Control and the Bolometer Analog System. The Bolometer Digital Control can control 16 bolometer bridges through the Bolometer Analog System. The Bolometer Digital Control, based on the FPGA architecture, is connected via Ethernet with a PC; therefore, it can receive commands settings from the PC and send the stream of bolometric measurements in real time to the PC. In order to solve the cross-talk between the bridges and the cables, each of the four bridges in the bolometer head receives a different synthesized excitation frequency. Since the system is fully controlled by a PC GUI (Graphic User Interface), it is very user friendly. Moreover, some useful features have been developed, such as: auto off-set correction, bridge amplitude regulation, software gain setting, real time visualization, frequency excitation selection and noise spectrum analyzer embedded function. In this paper, the

  18. FTU bolometer electronic system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Pollastrone, Fabio, E-mail: fabio.pollastrone@enea.it [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Neri, Carlo; Florean, Marco; Ciccone, Giovanni [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy)

    2013-10-15

    Highlights: ► Design and realization of a new bolometer electronic system. ► Many improvements over the actual commercial system. ► Architecture based on digital electronic hardware with minimal analog front end. ► Auto off-set correction, real time visualization features and small system size. ► Test results for the electronic system. -- Abstract: The FTU (Frascati Tokamak Upgrade) requires a bolometer diagnostic in order to measure the total plasma radiation. The current diagnostic architecture is based on a full analog multichannel AC bolometer system, which uses a carrier frequency amplifier with a synchronous demodulation. Taking into account the technological upgrades in the field of electronics, it was decided to realize an upgrade for the bolometric electronic system by using a hybrid analog/digital implementation. The new system developed at the ENEA Frascati laboratories has many improvements, and mainly a massive system volume reduction, a good measurement linearity and a simplified use. The new hardware system consists of two subsystems: the Bolometer Digital Control and the Bolometer Analog System. The Bolometer Digital Control can control 16 bolometer bridges through the Bolometer Analog System. The Bolometer Digital Control, based on the FPGA architecture, is connected via Ethernet with a PC; therefore, it can receive commands settings from the PC and send the stream of bolometric measurements in real time to the PC. In order to solve the cross-talk between the bridges and the cables, each of the four bridges in the bolometer head receives a different synthesized excitation frequency. Since the system is fully controlled by a PC GUI (Graphic User Interface), it is very user friendly. Moreover, some useful features have been developed, such as: auto off-set correction, bridge amplitude regulation, software gain setting, real time visualization, frequency excitation selection and noise spectrum analyzer embedded function. In this paper, the

  19. Comparing the effects of feeding a grain- or a fish meal-based diet on water quality, waste production, and rainbow trout Oncorhynchus mykiss performance within low exchange water recirculating aquaculture systems

    Science.gov (United States)

    Feeding a fish meal-free grain-based diet (GB) was compared to feeding a fish meal-based diet (FM) relative to water quality criteria, waste production, water treatment process performance, and rainbow trout Oncorhynchus mykiss performance within six replicated water recirculating aquaculture system...

  20. Evaluation of the impact of nitrate-nitrogen levels in recirculating aquaculture systems on concentrations of the off-flavor compounds geosmin and 2-methylisoborneol in water and rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Aquatic animals raised in recirculating aquaculture systems (RAS) can develop preharvest “off-flavors” such as “earthy” or “musty” which are caused by the bioaccumulation of the odorous compounds geosmin or 2-methylisoborneol (MIB), respectively, in their flesh. Tainted aquatic products cause large...

  1. Evaluation of depuration procedures to mitigate the off-flavor compounds geosmin and 2-methylisoborneol from Atlantic salmon Salmo salar raised to market-size in recirculating aquaculture systems

    Science.gov (United States)

    Fish cultured within water recirculating aquaculture systems (RAS) can acquire “earthy” or “musty” off-flavors due to bioaccumulation of the compounds geosmin and 2-methylisoborneol (MIB), respectively, which are produced by certain bacterial species present in RAS biosolids and microbial biofilms. ...

  2. Monitoring System Design of Aquaculture Environment Based on ZigBee%基于ZigBee的水产养殖监测系统设计

    Institute of Scientific and Technical Information of China (English)

    陈彪; 袁琦

    2014-01-01

    为实现水产养殖环境的现场数据实时采集、处理和无线传输,开发了基于 Zigbee的水产养殖环境监测系统。该系统采用组态王设计电脑主界面,硬件和软件的实现主要利用 CC2430的硬件资源及ZigBee协议的无线组网功能,实现了对温度、p H值、溶解氧的参数采集与显示、储存、超限报警、历史数据查询、无线传输、数据报表导出等功能,整套系统数据采集正常、稳定性好,且系统具有人机界面友好、操作简便、低复杂性、成本低的特点。%The monitoring system of aquaculture environment is successfully developed based on ZigBee to realize field data real-time collection, dispose and wireless transmission of aquaculture environment.The main interface, hardware and software of the system are established by CC2430 hardware resources & ZigBee protocol, which can realize the collection, display, storage, over-limit alarm,historical data query,wireless transmission,export data report of temperature,pH and dissolved oxygen parameters.The system with normal and stable data collection has the advantages of friendly man-machine interface,easy operation,low complexity and lower cost.

  3. Application of a fluidized bed reactor charged with aragonite for control of alkalinity, pH and carbon dioxide in marine recirculating aquaculture systems

    Science.gov (United States)

    Paul S Wills, PhD; Pfeiffer, Timothy; Baptiste, Richard; Watten, Barnaby J.

    2016-01-01

    Control of alkalinity, dissolved carbon dioxide (dCO2), and pH are critical in marine recirculating aquaculture systems (RAS) in order to maintain health and maximize growth. A small-scale prototype aragonite sand filled fluidized bed reactor was tested under varying conditions of alkalinity and dCO2 to develop and model the response of dCO2 across the reactor. A large-scale reactor was then incorporated into an operating marine recirculating aquaculture system to observe the reactor as the system moved toward equilibrium. The relationship between alkalinity dCO2, and pH across the reactor are described by multiple regression equations. The change in dCO2 across the small-scale reactor indicated a strong likelihood that an equilibrium alkalinity would be maintained by using a fluidized bed aragonite reactor. The large-scale reactor verified this observation and established equilibrium at an alkalinity of approximately 135 mg/L as CaCO3, dCO2 of 9 mg/L, and a pH of 7.0 within 4 days that was stable during a 14 day test period. The fluidized bed aragonite reactor has the potential to simplify alkalinity and pH control, and aid in dCO2 control in RAS design and operation. Aragonite sand, purchased in bulk, is less expensive than sodium bicarbonate and could reduce overall operating production costs.

  4. Literature review of the potential effects of hydrogen peroxide on nitrogen oxidation efficiency of the biofilters of recirculating aquaculture systems (RAS) for freshwater finfish

    Science.gov (United States)

    Fredricks, Kim T.

    2015-01-01

    A comprehensive literature review was done for the effects of hydrogen peroxide (HP) on biofilter function in recirculating aquaculture systems (RAS) using these databases: ISI/Web of Knowledge, Scopus, and Pubmed. Inclusion and exclusion criteria were developed as the literature review was conducted. The initial search produced 5,748 potential citations. Once the literature search was complete, these 5,748 titles were screened for applicable papers using the inclusion and exclusion criteria. If the title contained any of the inclusion terms, it was retained. Titles of the remaining papers were then screened for exclusion terms. If the title contained one or more of the exclusion terms, it was eliminated from further consideration. This refined search produced 1,405 papers.

  5. Literature review of the potential effects of formalin on nitrogen oxidation efficiency of the biofilters of recirculating aquaculture systems (RAS) for freshwater finfish

    Science.gov (United States)

    Fredricks, Kim T.

    2015-01-01

    A comprehensive literature review was done for the effects of formalin on biofilter function in recirculating aquaculture systems (RAS) using these databases: ISI/Web of Knowledge, Scopus, and Pubmed. Inclusion and exclusion criteria were developed as the literature review was conducted. The initial search produced 5,682 potential citations. Once the literature search was complete, these 5,682 titles were screened for applicable papers using the inclusion and exclusion criteria. If the title contained any of the inclusion terms, it was retained. Titles of the remaining papers were then screened for exclusion terms. If the title contained one or more of the exclusion terms, it was eliminated from further consideration. This refined search produced 1,287 papers.

  6. Direct utilization of geothermal heat in cascade application to aquaculture and greenhouse systems at Navarro College. Final report, March 1, 1979-September 30, 1984

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.

    1984-09-01

    This final report documents the Navarro College geothermal use project, which is one of nineteen direct-use geothermal projects funded principally by DOE. The six-year project encompassed a broad range of technical, institutional, and economic activities including: resource and environmental assessment; well drilling and completion; system design, construction, and monitoring; economic analysis; and public awareness programs. Some of the project conclusions are that: (1) the 130/sup 0/F Central Texas geothermal resource can support additional geothermal development; (2) private sector economic incentives currently exist which encourage commercial development of this geothermal resource; (3) potential uses for this geothermal resource include water and space heating, aquacultural and agricultural heating uses, and fruit and vegetable dehydration; (4) high maintenance costs arising from the geofluids' scaling and corrosion characteristics can be avoided through proper analysis and design.

  7. Effect of Recirculating Aquaculture System (RAS on Growth Performance, Body Composition and Hematological Indicators of Allogynogenetic crucian Carp (Carassius auratus gibelio

    Directory of Open Access Journals (Sweden)

    Xiao-li Li

    2013-03-01

    Full Text Available A Ditch Constructed Wetland unit (DCW was integrated into an outdoor RAS with four fishponds. This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of Recirculating Aquaculture System (RAS on growth performance, body composition and hematological indicators of the rearing fish. During a 165-days culture period, the DCW effectively reduced the influent concentrations of nutrients and can keep a good water quality at acceptable concentrations for growth of the fish. Growth performance, body composition and hematological indicators of Allogynogenetic crucian carp were closely related to water quality of their living environment. The RAS had improved the growth performance and quality of Allogynogenetic crucian carp.

  8. Generative electronic background music system

    International Nuclear Information System (INIS)

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions

  9. Generative electronic background music system

    Energy Technology Data Exchange (ETDEWEB)

    Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

    2015-03-10

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

  10. The influence of stocking density on growth performance and hematological profile of stellate sturgeon (A. stellatus, Pallas, 1771, reared in an industrial ,, flow-through’’ aquaculture system

    Directory of Open Access Journals (Sweden)

    Desimira Maria Dicu Stroe

    2013-10-01

    Full Text Available 800x600 The aim of this paper is to evaluate the influence of four different stocking densities, ranging from 18.7 to 28.6 kg m3, on growth performance and welfare of juvenile stellate sturgeons, reared in an industrial ,,flow-through’’ aquaculture system. At the end of 60 days experimental period, a survival rate of 98% and a stocking density that ranged from 32.5 to 39.8 kg m-3 were registered. The physiological state of biological material is characterized by the values ​​of hematological indices, that are not significant from the statistical point of view (p> 0.05, both at the beginning and at the end of experimental period, as well as between experimental variants. To assess the biological material growth performance, feed conversion ratio (FCR, specific growth rate (SGR and profile index were calculated. Regarding the growth performance parameters, better value are encountered at B1 (18.7 kg m-3 and B3 (23.3 kg m-3, appreciable values ​​at B2 (20.4 kg m-3 and low values at B4 (28.6 kg m-3. As conclusion, it can be assert that the initial stocking density of 28.6 kg m-3 is not optimal for rearing juvenile stellate sturgeons in an industrial ,,flow-through’’ aquaculture system. Normal 0 21 false false false RO X-NONE X-NONE MicrosoftInternetExplorer4

  11. Field reliability of electronic systems

    International Nuclear Information System (INIS)

    This report investigates, through several examples from the field, the reliability of electronic units in a broader sense. That is, it treats not just random parts failure, but also inadequate reliability design and (externally and internally) induced failures. The report is not meant to be merely an indication of the state of the art for the reliability prediction methods we know, but also as a contribution to the investigation of man-machine interplay in the operation and repair of electronic equipment. The report firmly links electronics reliability to safety and risk analyses approaches with a broader, system oriented view of reliability prediction and with postfailure stress analysis. It is intended to reveal, in a qualitative manner, the existence of symptom and cause patterns. It provides a background for further investigations to identify the detailed mechanisms of the faults and the remedical actions and precautions for achieving cost effective reliability. (author)

  12. PROTEOMICS in aquaculture

    DEFF Research Database (Denmark)

    Rodrigues, Pedro M.; Silva, Tomé S.; Dias, Jorge;

    2012-01-01

    growth in production is still expected for decades to come. Aquaculture is, though, a very competitive market, and a global awareness regarding the use of scientific knowledge and emerging technologies to obtain a better farmed organism through a sustainable production has enhanced the importance......Over the last forty years global aquaculture presented a growth rate of 6.9% per annum with an amazing production of 52.5million tonnes in 2008, and a contribution of 43% of aquatic animal food for human consumption. In order to meet the world's health requirements of fish protein, a continuous...... nutritional, health or quality properties for functional foods and the integration of proteomics techniques in addressing this challenging issue. This article is part of a Special Issue entitled: Farm animal proteomics....

  13. Power electronic systems Walsh analysis with Matlab

    CERN Document Server

    Deb, Anish

    2014-01-01

    A Totally Different Outlook on Power Electronic System AnalysisPower Electronic Systems: Walsh Analysis with MATLAB® builds a case for Walsh analysis as a powerful tool in the study of power electronic systems. It considers the application of Walsh functions in analyzing power electronic systems, and the advantages offered by Walsh domain analysis of power electronic systems. Solves Power Electronic Systems in an Unconventional WayThis book successfully integrates power electronics as well as systems and control. Incorporating a complete orthonormal function set very much unlike the sine-cosin

  14. Analyzing and Evaluating of Recirculating Aquaculture Systems (RAS of Rainbow Trout in Order to Designing a Conceptual Model of Efficient RAS in Iran (Tehran

    Directory of Open Access Journals (Sweden)

    M. Mahmoodzadeh

    2013-09-01

    Full Text Available In this study, Recirculation Aquaculture Systems (RAS of rainbow trout were analyzed and evaluated in Iran (Tehran. After analyzing these systems it was found which of them were better than others and then their parameters were used for designing a conceptual model of efficient RAS. This study was conducted in Iran (Tehran in 2012 and statistical population and samples were 8 systems. Systems were analyzed and evaluated by five criteria which were as follows: economy, energy, consumption and recycling of water, technical and engineering and management. Analyzing and evaluating were conducted by Data Envelopment Analysis (DEA method and also GAMS software was used for solving DEA model. It was found that in economy, energy, water consumption and recycling, technical and engineering and management criteria systems were efficient systems respectively. Based on the results, system 3th with regard to all the criteria was efficient system. Quality and quantity factors and equipments of system 3th were used in order to design a conceptual model of RAS in rainbow trout.

  15. Marketing netcoatings for aquaculture.

    Science.gov (United States)

    Martin, Robert J

    2014-01-01

    Unsustainable harvesting of natural fish stocks is driving an ever growing marine aquaculture industry. Part of the aquaculture support industry is net suppliers who provide producers with nets used in confining fish while they are grown to market size. Biofouling must be addressed in marine environments to ensure maximum product growth by maintaining water flow and waste removal through the nets. Biofouling is managed with copper and organic biocide based net coatings. The aquaculture industry provides a case study for business issues related to entry of improved fouling management technology into the marketplace. Several major hurdles hinder entry of improved novel technologies into the market. The first hurdle is due to the structure of business relationships. Net suppliers can actually cut their business profits dramatically by introducing improved technologies. A second major hurdle is financial costs of registration and demonstration of efficacy and quality product with a new technology. Costs of registration are prohibitive if only the net coatings market is involved. Demonstration of quality product requires collaboration and a team approach between formulators, net suppliers and farmers. An alternative solution is a vertically integrated business model in which the support business and product production business are part of the same company. PMID:25329615

  16. Marketing netcoatings for aquaculture.

    Science.gov (United States)

    Martin, Robert J

    2014-10-17

    Unsustainable harvesting of natural fish stocks is driving an ever growing marine aquaculture industry. Part of the aquaculture support industry is net suppliers who provide producers with nets used in confining fish while they are grown to market size. Biofouling must be addressed in marine environments to ensure maximum product growth by maintaining water flow and waste removal through the nets. Biofouling is managed with copper and organic biocide based net coatings. The aquaculture industry provides a case study for business issues related to entry of improved fouling management technology into the marketplace. Several major hurdles hinder entry of improved novel technologies into the market. The first hurdle is due to the structure of business relationships. Net suppliers can actually cut their business profits dramatically by introducing improved technologies. A second major hurdle is financial costs of registration and demonstration of efficacy and quality product with a new technology. Costs of registration are prohibitive if only the net coatings market is involved. Demonstration of quality product requires collaboration and a team approach between formulators, net suppliers and farmers. An alternative solution is a vertically integrated business model in which the support business and product production business are part of the same company.

  17. Structural Dynamics of Electronic Systems

    Science.gov (United States)

    Suhir, E.

    2013-03-01

    The published work on analytical ("mathematical") and computer-aided, primarily finite-element-analysis (FEA) based, predictive modeling of the dynamic response of electronic systems to shocks and vibrations is reviewed. While understanding the physics of and the ability to predict the response of an electronic structure to dynamic loading has been always of significant importance in military, avionic, aeronautic, automotive and maritime electronics, during the last decade this problem has become especially important also in commercial, and, particularly, in portable electronics in connection with accelerated testing of various surface mount technology (SMT) systems on the board level. The emphasis of the review is on the nonlinear shock-excited vibrations of flexible printed circuit boards (PCBs) experiencing shock loading applied to their support contours during drop tests. At the end of the review we provide, as a suitable and useful illustration, the exact solution to a highly nonlinear problem of the dynamic response of a "flexible-and-heavy" PCB to an impact load applied to its support contour during drop testing.

  18. Background paper on aquaculture research

    OpenAIRE

    Wenblad, Axel; Jokumsen, Alfred; Eskelinen, Unto; Torrissen, Ole

    2013-01-01

    The Board of MISTRA established in 2012 a Working Group (WG) on Aquaculture to provide the Board with background information for its upcoming decision on whether the foundation should invest in aquaculture research. The WG included Senior Advisor Axel Wenblad, Sweden (Chairman), Professor Ole Torrissen, Norway, Senior Advisory Scientist Unto Eskelinen, Finland and Senior Advisory Scientist Alfred Jokumsen, Denmark. The WG performed an investigation of the Swedish aquaculture sector including ...

  19. Aquaculture Integrated Environmental Monitoring System for Research and Development%水产养殖综合环境在线监测系统的研究与开发

    Institute of Scientific and Technical Information of China (English)

    刘红刚; 陈艺

    2012-01-01

      The aquaculture industry is facing the stocking density is too high, the weak awareness of the protection of the culture environment, breeding and showed a trend of increasing year on year, the waters were varying degrees of damage to the environment, sustainable aquaculture development have been seriously affected, study and solve the aquaculture environmental conditionshas become an important subject of sustained and healthy development of the aquaculture industry, the project is based on the realities of the current aquaculture, integrated embedded software and hardware development technology, wireless communication technology,multi-sensor,multi-channel data acquisition technology, solar-powered technology, GIStechnology and information fusion technology to develop a multi-measurement elements in one multifunctional aquaculture environment online monitoring system that can effectively help the aquaculture industry to effectively solve the problem of aquatic environmental monitoring. Article the system works, design ideas, the system features described in detail.%  当前水产养殖行业面临着养殖密度过高,保护养殖环境意识淡薄,养殖病害呈逐年加重之势,水域环境遭到不同程度的破坏,水产养殖业可持续发展受到严重影响,研究解决水产养殖环境状况已经成为水产养殖业持续健康发展的重要课题,本项目基于当前水产养殖的现实情况,提出综合应用嵌入式软硬件开发技术、无线通信技术、多传感器多通道数据采集技术、太阳能供电技术、GIS技术以及信息融合技术开发集多种测量要素于一体的多功能的水产养殖综合环境在线监测系统,可以有效帮助水产养殖业者有效解决水产环境监控问题。文章对该系统的工作原理、设计思路、系统功能特点进行了详细的阐述

  20. 对虾高位池循环水养殖水体浮游动物生态特征研究%Ecological Characteristics of Zooplankton in the Higher Place Pond of Shrimp Recirculating Aquaculture System

    Institute of Scientific and Technical Information of China (English)

    魏小岚; 李纯厚; 颉晓勇; 戴明; 廖秀丽; 胡维安; 肖雅元; 李朋

    2013-01-01

    为了掌握对虾高位池循环水养殖过程中浮游动物的变动规律,有效管理水体环境质量,提高养殖效益,于2010年8月-11月,以凡纳滨对虾(Litopenaeus vannarnei)为试验对象,研究了循环水处理高位池养殖水体中浮游动物的群落结构及其动态变化,试验设计3种不同循环处理量组,即20 m3·h-1(P1组)、40 m3·h-1(P2组)和60 m3·h-1(P3组),探讨不同的循环水处理量和养殖模式对水体中浮游动物的生态特征影响.结果表明,从各试验塘鉴定出浮游动物主要隶属于四大类,循环塘21属35种,对照塘43属61种,种类最多的为轮虫,占总数的34.4%,其次为原生动物,占总数的31.1%,再次为枝角类,占总数的19.7%,最后为桡足类,占总数的14.8%.循环塘的优势种以原生动物和轮虫为主,而对照塘试验中后期的浮游动物以大型甲壳动物为主,循环塘和对照塘中浮游动物的密度分别为:131.52~497.17 ind· L-1和122.09~373.15 ind·L-1,其生物量分别为1.19~3.87 mg·L-1和0.64~3.01 mg· L-1,循环塘中浮游动物的密度和生物量明显高于对照塘,且存在显著性差异(P<0.05).循环塘浮游动物Shannon-Wiener多样性指数(H’)在1.01~2.08之间波动,而对照塘浮游动物多样性指数(H’)在0.76~1.56之间波动.%shrimp recirculating aquaculture system, to effective manage environmental quality of cultured waters, and to rise cultured benefit. From August to November in 2010, by Litopenaeus vannarnei as experimental object was research in the higher place pond of shrimp recirculating aquaculture system. Experiments were designed three different recirculating treatment groups, they were 20 m3-h-1 (Group of pond one), 40 m3>h-1'( Group of pond two) and 60 m3-h-1( Group of pond three), respectively. Community structure and its dynamic changes of zooplankton were studied in the higher-place pond of shrimp recirculating aquaculture system. The experimental results showed that

  1. Phenotypic and molecular characterisation of fish-borne Flavobacterium johnsoniae-like isolates from aquaculture systems in South Africa.

    Science.gov (United States)

    Flemming, Leonard; Rawlings, Douglas; Chenia, Hafizah

    2007-01-01

    Fish infections caused by pathogenic Flavobacterium species are a major problem in the aquaculture industry worldwide, often leading to large economic losses. Thirty-two Flavobacterium spp. isolates, obtained from various diseased fish species and biofilm growth, were characterised genetically using 16S rDNA PCR restriction fragment length polymorphism (RFLP), randomly amplified polymorphic DNA (RAPD) PCR, repetitive extragenic palindromic (REP) element PCR, plasmid profiling, whole cell protein (WCP) and outer membrane protein (OMP) analyses. Although the Flavobacterium spp. isolates displayed a high degree of genetic heterogeneity when differentiated by RAPD-PCR, REP-PCR and OMP fingerprinting techniques, isolates appeared very homogeneous by plasmid profiling and WCP analysis. No specific correlation was observed between the RAPD, REP and/or OMP profiles and fish host, site of isolation, geographic location or date of isolation of the Flavobacterium spp. isolates. Experimental infection of tilapia fish revealed variable levels of virulence and pathogenicity by isolates following handling stress and could not be linked to specific molecular types. This is the first reported isolation and characterisation of Flavobacterium johnsoniae-like spp. isolated from diseased fish in Southern Africa. PMID:17113757

  2. Nitrous oxide (N2O) emission from aquaculture: a review.

    Science.gov (United States)

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Khanal, Samir Kumar

    2012-06-19

    Nitrous oxide (N(2)O) is an important greenhouse gas (GHG) which has a global warming potential 310 times that of carbon dioxide (CO(2)) over a hundred year lifespan. N(2)O is generated during microbial nitrification and denitrification, which are common in aquaculture systems. To date, few studies have been conducted to quantify N(2)O emission from aquaculture. Additionally, very little is known with respect to the microbial pathways through which N(2)O is formed in aquaculture systems. This review suggests that aquaculture can be an important anthropogenic source of N(2)O emission. The global N(2)O-N emission from aquaculture in 2009 is estimated to be 9.30 × 10(10) g, and will increase to 3.83 × 10(11)g which could account for 5.72% of anthropogenic N(2)O-N emission by 2030 if the aquaculture industry continues to increase at the present annual growth rate (about 7.10%). The possible mechanisms and various factors affecting N(2)O production are summarized, and two possible methods to minimize N(2)O emission, namely aquaponic and biofloc technology aquaculture, are also discussed. The paper concludes with future research directions.

  3. Heterotrophic denitrification of aquaculture effluent using fluidized sand biofilters

    Science.gov (United States)

    The ability to consistently and cost-effectively reduce nitrate-nitrogen loads in effluent from recirculating aquaculture systems would enhance the industry's environmental stewardship and allow improved facility proximity to large markets in sensitive watersheds. Heterotrophic denitrification techn...

  4. Green and technical efficient growth in Danish fresh water aquaculture

    DEFF Research Database (Denmark)

    Nielsen, Rasmus

    2011-01-01

    Aquaculture is the fastest growing animal food processing sector in the world. Nevertheless, growth inside the Organization for Economic Co-operation and Development has been stagnating, with few exceptions. The main reason is strict environmental regulations. This study investigates if green...... growth can be achieved by introducing new environmentally friendly water purification systems in Danish fresh water aquaculture. Data Envelopment Analysis is used to investigate whether different water purification systems and farm size influence technical efficiency. The empirical results indicate...

  5. Application of Water Treatment Equipment in Recirculating Aquaculture System%循环水养殖系统中水处理设备的应用技术

    Institute of Scientific and Technical Information of China (English)

    宋红桥; 管崇武

    2011-01-01

    水产养殖的水处理技术是发展循环水养殖技术的关键,该文根据国内的水处理技术,结合国内外有关水产养殖水处理技术的研究结果,论述了目前水产养殖水处理技术的主要方法,为在养殖系统应用中提供相应的依据。%Water treatment technology is the key to develep recireulating aquaculture. The paper mainly discussed of the current aquaculture water treatment technology, according to the domestic and abroad aquaculture water treatment technology. It was the basic study for aquaculture application.

  6. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed

  7. DNA vaccines for aquacultured fish

    DEFF Research Database (Denmark)

    Lorenzen, Niels; LaPatra, S.E.

    2005-01-01

    of licensing and public acceptance of the technology. The potential benefits of DNA vaccines for farmed fish include improved animal welfare, reduced environmental impacts of aquaculture activities, increased food quality and quantity, and more sustainable production. Testing under commercial production......Deoxyribonucleic acid (DNA) vaccination is based on the administration of the gene encoding the vaccine antigen, rather than the antigen itself. Subsequent expression of the antigen by cells in the vaccinated hosts triggers the host immune system. Among the many experimental DNA vaccines tested...... in various animal species as well as in humans, the vaccines against rhabdovirus diseases in fish have given some of the most promising results. A single intramuscular (IM) injection of microgram amounts of DNA induces rapid and long-lasting protection in farmed salmonids against economically important...

  8. Disease and health management in Asian aquaculture.

    Science.gov (United States)

    Bondad-Reantaso, Melba G; Subasinghe, Rohana P; Arthur, J Richard; Ogawa, Kazuo; Chinabut, Supranee; Adlard, Robert; Tan, Zilong; Shariff, Mohamed

    2005-09-30

    Asia contributes more than 90% to the world's aquaculture production. Like other farming systems, aquaculture is plagued with disease problems resulting from its intensification and commercialization. This paper describes the various factors, providing specific examples, which have contributed to the current disease problems faced by what is now the fastest growing food-producing sector globally. These include increased globalization of trade and markets; the intensification of fish-farming practices through the movement of broodstock, postlarvae, fry and fingerlings; the introduction of new species for aquaculture development; the expansion of the ornamental fish trade; the enhancement of marine and coastal areas through the stocking of aquatic animals raised in hatcheries; the unanticipated interactions between cultured and wild populations of aquatic animals; poor or lack of effective biosecurity measures; slow awareness on emerging diseases; the misunderstanding and misuse of specific pathogen free (SPF) stocks; climate change; other human-mediated movements of aquaculture commodities. Data on the socio-economic impacts of aquatic animal diseases are also presented, including estimates of losses in production, direct and indirect income and employment, market access or share of investment, and consumer confidence; food availability; industry failures. Examples of costs of investment in aquatic animal health-related activities, including national strategies, research, surveillance, control and other health management programmes are also provided. Finally, the strategies currently being implemented in the Asian region to deal with transboundary diseases affecting the aquaculture sector are highlighted. These include compliance with international codes, and development and implementation of regional guidelines and national aquatic animal health strategies; new diagnostic and therapeutic techniques and new information technology; new biosecurity measures including

  9. Electronic Nicotine Delivery Systems Key Facts Infographic

    Data.gov (United States)

    U.S. Department of Health & Human Services — Explore the Electronic Nicotine Delivery Systems Key Facts Infographic which outlines key facts related to electronic nicotine delivery systems (ENDS), including...

  10. Reliability of Power Electronic Converter Systems

    DEFF Research Database (Denmark)

    The main aims of power electronic converter systems (PECS) are to control, convert, and condition electrical power flow from one form to another through the use of solid-state electronics. This book outlines current research into the scientific modeling, experimentation, and remedial measures...... electronic converter systems; anomaly detection and remaining-life prediction for power electronics; reliability of DC-link capacitors in power electronic converters; reliability of power electronics packaging; modeling for life-time prediction of power semiconductor modules; minimization of DC......-link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault...

  11. Rapeseed use in aquaculture

    Directory of Open Access Journals (Sweden)

    Adem Halime Nihat

    2014-01-01

    Full Text Available The main problem of the aquaculture sector is the provision of suitable and sufficient fish feed, because the most important protein source in aquaculture, the fish meal, is a limited resource. Due to their high nutritional value the rapeseed proteins have great potential as an alternative protein source for the fish nutrition. Therefore, the aim of this work is to develop a manufacturing process of high quality rapeseed protein concentrates, which can replace the limited marine resource. For this purpose, small pilot scale processing procedures were performed to produce a rapeseed protein concentrate (RPC. The meal for protein extraction was prepared by gentle meal processing. Rapeseed protein fractions were prepared by an aqueous extraction procedure. The obtained protein solution is further purified and then dried. The investigated rapeseed protein extraction process provides RPC with high nutritional value and low levels of antinutritional factors. From the nutritional point of view the produced RPC can be compared with the fishmeal. Its amino acid profile reflects the amino acid demands of fish. The obtained RPC was utilized for experimental setups of fish meal replacement in diets for rainbow trout, turbot, common carp and wels catfish. Experimental results from the conducted feeding trials demonstrate an enormous potential of RPC as protein source in aquafeeds. The highest fishmeal replacement level (up to 100% was observed in the feeding trials with rainbow trout. Therefore, especially in the nutrition of rainbow trout, RPC was identified as an excellent fishmeal alternative.

  12. Optimizing nitrate removal in woodchip beds treating aquaculture effluents

    DEFF Research Database (Denmark)

    von Ahnen, Mathis; Pedersen, Per Bovbjerg; Hoffmann, Carl Christian;

    2016-01-01

    Nitrate is typically removed from aquaculture effluents using heterotrophic denitrification reactors. Heterotrophic denitrification reactors, however, require a constant input of readily available organic carbon (C) sources which limits their application in many aquaculture systems for practical...... the potential of optimizing woodchip reactors for treating aquaculture effluent. A central composite design (CCD) was applied to assess the effects of simultaneously changing the empty bed contact time (EBCTs of 5.0-15.0 h; corresponding to theoretical hydraulic retention times of 3.3-9.9 h) and bicarbonate...... (HCO3 -) inlet concentration (0.50-1.59 g HCO3 -/l) on the removal rate of NO3 -N, and additional organic and inorganic nutrients, in effluent deriving from an experimental recirculating aquaculture system (RAS).Volumetric NO3 -N removal rates ranged from 5.20 ± 0.02 to 8.96 ± 0.19 g/m3/day and were...

  13. The use of marine aquaculture solid waste for nursery production of the salt marsh plants Spartina alterniflora and Juncus roemerianus

    OpenAIRE

    H.M. Joesting; R. Blaylock; P. Biber; A. Ray

    2016-01-01

    Recent technological advances in marine shrimp and finfish aquaculture alleviate many of the environmental risks associated with traditional aquaculture, but challenges remain in cost-effective waste management. Liquid effluent from freshwater aquaculture systems has been shown to be effective in agricultural crop production (i.e., aquaponics), but few studies have explored the potential for reuse of marine aquaculture effluent, particularly the solid fraction. The purpose of this study was t...

  14. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture

    OpenAIRE

    S. Sumoharjo; Asfie Maidie

    2013-01-01

    Integrated multi-trophic aquaculture pays more attention as a bio-integrated food production system that serves as a model of sustainable aquaculture, minimizes waste discharge, increases diversity and yields multiple products. The objectives of this research were to analyze the efficiency of total ammonia nitrogen biofiltration and its effect on carrying capacity of fish rearing units. Pilot-scale bioreactor was designed with eight run-raceways (two meters of each) that assembled in series. ...

  15. 冬季罗非鱼循环水暂养系统研究%Study on the temporary rearing of tilapia in recirculating aquaculture system in winter

    Institute of Scientific and Technical Information of China (English)

    周游; 陈石; 张成林

    2015-01-01

    为探索解决罗非鱼越冬问题,开展了利用循环水养殖系统进行暂养的试验研究。以具有代表性的吉富罗非鱼( Orcochromis niloticus)为研究对象,设计并构建了一套室内罗非鱼循环水养殖系统,并对罗非鱼进行了为期30 d的养殖试验。整个养殖周期内,罗非鱼养殖系统环境稳定、水质稳定良好。结果显示,系统养殖负荷总量从1024.2 kg增长到2309.1kg,鱼体平均体重由(170.7±10.8) g增重至(385.5±7.5) g,养殖密度由(22.9±3.5) kg/m3增加到(51.5±4.2) kg/m3,存活率达99.8%,饵料系数1.35。水质检测结果显示,水体进水口总氨氮0.21~0.33 mg/L,去除率20.64%;亚硝酸盐氮0.067~0.13 mg/L,去除率13.82%;溶氧6.5~7.4 mg/L,pH8.15~8.65,水温23.9~24.7℃。研究表明,罗非鱼生长状况良好,系统中各水质参数符合养殖要求。循环水养殖系统用于罗非鱼冬季暂养具有一定的可行性。%In order to enrich the data of temporary rearing system in the real production of tilapia in winter, an experimental study on the use of the recirculating aquaculture system for the breeding of tilapia ( Orcochromis niloticus) was conducted.The recirculating aquaculture system was evaluated as culture environments for tilapia were reared in the system for 30 days.Throughout the experiment, water quality parameters were stable and remained within ranges suitable for tilapias.The experiment results showed that:the carrying capacity of the farming system increased from 1 024.2 kg to 2 309.1 kg.The average body weight increased from (170.7 ±10.8) g to (385.5 ±7.5) g, and the stocking density of the fish increased from (22.9 ±14.5) kg/m3 to (51.5 ±10.2) kg/m3 .The survival rate was 99.8%.The feed coefficient ratio was 1.35.Water quality test results showed:the contents of ammonia nitrogen from fish pond water inlet was 0

  16. Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

    Science.gov (United States)

    Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

    2014-12-01

    In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the

  17. Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

    Science.gov (United States)

    Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

    2014-12-01

    In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the

  18. 基于ZigBee的水产养殖水环境无线监控系统设计%Design of a wireless water environment monitoring system based on ZigBee in aquaculture

    Institute of Scientific and Technical Information of China (English)

    宦娟; 刘星桥; 程立强; 孙雷霸; 李成春

    2012-01-01

    Monitoring the living environment of fish accurately and quickly plays an important role in the aquaculture industry. The water environment monitoring in aquaculture has the characteristics of multi-measuring points, long measuring time, and high complexity measuring conditions. A new type of wireless sensor network system for aquaculture based on ZigBee was designed and constructed. This system achieved the goals of collect, transmit and display multi-parameters, such as dissolved oxygen ( DO) , pH and temperature. By using wireless sensor network, transmissions of the data between sensor detecting nodes and coordinate nodes are fast and accurate. The system also enforces real-time remote monitoring. Because of its simple structure, fast data transmission, easy functional extension, the system is suitable for industrialized aquaculture.%设计了一种基于ZigBee协议的水产养殖水环境无线监控系统,实现了对溶解氧、pH值、温度等多参数的采集、处理和显示,并通过无线网络实现了传感器检测节点和协调器节点之间数据快速、准确的传输,进而对多参数进行实时远程监测.该系统适用于工厂化水产养殖、水环境、智能温室等诸多领域.

  19. Monitoring and managing microbes in aquaculture - Towards a sustainable industry.

    Science.gov (United States)

    Bentzon-Tilia, Mikkel; Sonnenschein, Eva C; Gram, Lone

    2016-09-01

    Microorganisms are of great importance to aquaculture where they occur naturally, and can be added artificially, fulfilling different roles. They recycle nutrients, degrade organic matter and, occasionally, they infect and kill the fish, their larvae or the live feed. Also, some microorganisms may protect fish and larvae against disease. Hence, monitoring and manipulating the microbial communities in aquaculture environments hold great potential; both in terms of assessing and improving water quality, but also in terms of controlling the development of microbial infections. Using microbial communities to monitor water quality and to efficiently carry out ecosystem services within the aquaculture systems may only be a few years away. Initially, however, we need to thoroughly understand the microbiomes of both healthy and diseased aquaculture systems, and we need to determine how to successfully manipulate and engineer these microbiomes. Similarly, we can reduce the need to apply antibiotics in aquaculture through manipulation of the microbiome, i.e. by the use of probiotic bacteria. Recent studies have demonstrated that fish pathogenic bacteria in live feed can be controlled by probiotics and that mortality of infected fish larvae can be reduced significantly by probiotic bacteria. However, the successful management of the aquaculture microbiota is currently hampered by our lack of knowledge of relevant microbial interactions and the overall ecology of these systems. PMID:27452663

  20. Design and Implementation of Aquaculture Pond Water Quality Assessment System Based on Fuzzy Mathematics%池塘淡水养殖水质模糊综合评价系统的设计与实现

    Institute of Scientific and Technical Information of China (English)

    王瑞梅; 傅泽田; 何有缘

    2010-01-01

    以池塘淡水养殖水质为研究对象,在综合分析池塘水质各影响因子的基础上,通过专家问卷调查法和德尔裴法对水质因子的重要程度进行了排序,建立了池塘水质评价指杯体系和评价标准,用重要程度法和实测值相对隶属度法确定了指标权重,建立了池塘水质模糊综合评价模型,并设计和实现了淡水池塘养殖水质模糊综合评价系统.将该系统应用于某企业淡水养殖池塘水质的评价,取得了较好效果.%The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond wa-ter quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values.thus and the fuzzy comprehensive evaluation model of aquaculture pond water qualitv was constructed.and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quailty by a company had achieved better result.

  1. Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®-medicated feed therapy

    Science.gov (United States)

    Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

    2015-01-01

    Aquaflor® [50% w w−1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg−1 BW d−1 dose (1.33× the label use of 15 mg FFC kg−1 BW d−1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 μg g−1 at 1-h post dosing to 0.39 μg g−1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL−1 at 1 day post-dosing to 847 ng mL−1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

  2. 循环流水产养殖系统净化研究%Research on Purification of Recirculating Aquaculture System

    Institute of Scientific and Technical Information of China (English)

    汪辉; 马伟芳; 郭浩; 曾凡刚; 韩冬梅; 丁志伟

    2012-01-01

    文章研究了不同水力停留时间和壳聚糖的投加对循环流水产养殖系统的影响,结果表明,当水力停留时间为8h,系统内除磷,除氨氮、COD效果明显,通过生物滤池和植物滤池的去除,NO2^-浓度下降,植物滤池平均出水浓度总磷1.60mg/L、氨氮0.016mg/L、COD为21.788mg/L;养鱼池投加壳聚糖,出水的色度和浊度都明显降低。%This paper studied the influence of different hydraulic retention time and chitosan additive on recirculating aquaculture system. The results show that, when the hydraulic retention time was 8 h, the removal efficiency of phosphorus, ammonia nitrogen and COD was high. Through the bio - filter and plants filter, the NO2^- concentration dropped. In the effluent of plant filter, the average concentration of phosphorus, ammonia nitrogen and COD was 1.60 mg/L, 0. 016 mg/L and 21. 788 rag/L, respectively. The turbidity and chromaticity were obviously reduced by dosing ehitosan in the fish pond.

  3. Results regarding growth performance of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758 fed with an additive feed, vitamin C, in a recirculating aquaculture system.

    Directory of Open Access Journals (Sweden)

    Catalina Ciortan Mirea

    2013-10-01

    Full Text Available The aim of this study was to determine the vitamin C status on growth performance, survival rate and biochimical parameters from tissue of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758 with average weight of 93±1,0 g were fed with different dietary vitamin C rations and reared in a recirculating aquaculture system (RAS. Growth performance , survival rate and biochimical parameters from tissue of Nile tilapia were measured in groups fed diets supplemented with 100, 750, 2000 mg.kg-1L-ascorbic acid (AA and almost ascorbate free diet (Total AA> 5 mg.kg-1 as a control. They were stocked in 12 rearing units at 28 oC water temperature for 30 days. Diet of 33 % protein was offered as feed, 3 times daily. Growth measurements of tilapia were recorded on beginning and at the end of the experiment. Results showed that growth performance for Nile tilapia had not significantly (p>0.05 differences between the control and the tretments . Survival rate was the same for al the treatments. The feed conversio ratio (FCR was not significant (p>0.05 between the control and the treatments. Resuls showed that the feed impoved with AA had no significant differences between treatments and control regarding the  optimum growth performance and survival rate at Nile tilapia.  

  4. Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

    Science.gov (United States)

    Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

    2015-10-01

    The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P < 0.05). Feed conversion ratio (FCR) varied between 0.93 and 3.40, which was significantly affected by feed type ( P < 0.05), and slightly improved with increased satiation degree. The activities of digestive enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime ( P < 0.05), increasing with satiation degree. Flesh qualities for vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences ( P < 0.05), ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

  5. Application of chemical coagulation aids for the removal of suspended solids (TSS) and phosphorus from the microscreen effluent discharge of an intensive recirculating aquaculture system

    Science.gov (United States)

    Ebeling, J.M.; Ogden, S.R.; Sibrell, P.L.; Rishel, K.L.

    2004-01-01

    An evaluation of two commonly used coagulation-flocculation aids (alum and ferric chloride) was conducted to determine optimum conditions for treating the backwash effluent from microscreen filters in an intensive recirculating aquaculture system. Tests were carried out to evaluate the dosages and conditions (mixing and flocculation stirring speeds, durations, and settling times) required to achieve optimum waste capture. The orthophosphate removal efficiency for alum and ferric chloride were greater than 90% at a dosage of 60 mg/L. Optimum turbidity removal was achieved with a 60-mg/L dosage for both alum and ferric chloride. Both alum and ferric chloride demonstrated excellent removal of suspended solids from initial total suspended solid values of approximately 320 mg/L to approximately 10 mg/L at a dosage of 60 mg/L. Flocculation and mixing speed and duration played only a minor role in the removal efficiencies for both orthophosphates and suspended solids. Both coagulation-flocculation aids also exhibited excellent settling characteristics, with the majority of the floc quickly settling out in the first 5 min.

  6. Effects of spectral composition, photoperiod and light intensity on the gonadal development of Atlantic salmon Salmo salar in recirculating aquaculture systems (RAS)

    Science.gov (United States)

    Qiu, Denggao; Xu, Shihong; Song, Changbin; Chi, Liang; Li, Xian; Sun, Guoxiang; Liu, Baoliang; Liu, Ying

    2015-01-01

    Artificial lighting regimes have been successfully used to inhibit sexual maturity of Atlantic salmon in confinement. However, when these operations are applied in commercial recirculating aquaculture systems (RAS) using standard lighting technology, sexual maturation is not suppressed. In this study, an L9 (33) orthogonal design was used to determine the effects of three factors (spectral composition, photoperiod, and light intensity) on the gonadal development of Atlantic salmon in RAS. We demonstrated that the photoperiod at the tested levels had a much greater effect on the gonadosomatic index and female Fulton condition factor than spectral composition and light intensity. The photoperiod had a significant effect on the secretion of sex steroids and melatonin ( P0.05). The optimum lighting levels in female and male Atlantic salmon were LD 8:16, 455 nm (or 625 nm), 8.60 W/m2; and LD 8:16, 8.60 W/m2, 455 nm respectively. These conditions not only delayed gonadal development, but also had no negative effects on Atlantic salmon growth in RAS. These results demonstrate that a combination of spectral composition, photoperiod and light intensity is effective at delaying the gonadal development of both male and female salmon in RAS.

  7. Temperature effects on biomass, geosmin, and 2-methylisoborneol production and cellular activity by Nocardia spp. and Streptomyces spp. isolated from rainbow trout recirculating aquaculture systems.

    Science.gov (United States)

    Schrader, Kevin K; Harries, Marcuslene D; Page, Phaedra N

    2015-05-01

    Isolates of Nocardia cummidelens, Nocard ia fluminea, Streptomyces albidoflavus, and Streptomyces luridiscabiei attributed as the cause of "earthy-musty" off-flavor in rainbow trout (Oncorhynchus mykiss) raised in recirculating aquaculture systems (RAS) were evaluated for the effect of temperature (10-30 °C) on biomass, geosmin, and 2-methylisoborneol (MIB) production and cellular activity. Cultures of these isolates were monitored over 7 days by measuring culture dry weight, geosmin, and MIB production using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), and ATP production via a luminometer. Compared to the other isolates, S. luridiscabiei had significantly (P geosmin (69,976 ± 15,733 ng/L) at 15 °C. At 25 °C and 30 °C, S. albidoflavus produced significantly (P geosmin (182,074 ± 60,272 ng/L and 399,991 ± 102,262 ng/L, respectively). All isolates produced MIB at 15 °C, but S. luridiscabiei produced significantly (P geosmin and MIB in the RAS.

  8. 构建设施型精准化循环水养殖系统的技术研究%Study on the construction of the facility type precision recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    牛化欣; 常杰; 雷霁霖; 贾玉东

    2014-01-01

    鉴于当前水资源短缺、环境恶化、水产养殖业高速发展,以及保障食品安全等问题的不断呈现,促使资源型工厂化流水养殖模式急需向高效型循环水养殖方向转变,这是产业发展提升的必然趋势。本文以工业化养殖理念为指导、节能减排为目标,以鲆鲽类产业技术体系构建的循环水养殖模式为样板,按循环水养殖系统(RAS)的设计原理,优化养殖工艺流程,构建一种设施型精准化的RAS,并初步分析探讨了海水鱼类在此集成系统中的应用效果。该系统将为广大水产养殖企业提供一种建设成本低廉、系统运行稳定可控、容易管理的实用新型养殖模式,也可为下一步发展现代水产精准养殖工程体系提供理论和实践依据。%With the hot problem of the deepening of water shortage,environmental degrada-tion,efficient development of aquaculture,food safety and security,etc,which makes that the resource-based factory farming water is gradually an urgent need to efficient type recirculating aquaculture change. In this paper,industrialized farming concept as a guide,energy saving and emission reduction targets to agro-industrial technology research of flatfish system has been based on the model-based recirculating aquaculture systems(RAS)design principles to build accurate“conserving facility type”RAS,optimize their breeding process,and preliminary ex-ploration of marine fish in this integrated system. Low build the system for the majority of aqua-culture enterprises to provide a construction cost,the system is stable,practical farming model is easy to manage,but also for the further development of aquaculture in the establishment of modern precision engineering system to provide basic theory.

  9. Background paper on aquaculture research

    DEFF Research Database (Denmark)

    Wenblad, Axel; Jokumsen, Alfred; Eskelinen, Unto;

    80 million tonnes accounting for close to 50 % of all aquatic food destined for the global human consumption. The Swedish aquaculture production currently includes about 11,000 tonnes rainbow trout in FW and SW, 1,100 tonnes arctic char (FW), 90 tonnes eel (FW), 1,500 tonnes mussels (SW) and a few...... platform for cooperation on research and education, exchange and transfer of knowledge from research to aquaculture practice. Further, integration of biological and technological research combined with education and training of skilled professionals as well as authority staff dealing with aquaculture...... due to the availability of vast water resources of good quality (both marine and fresh water), a high veterinary status and generally well developed public infrastructure. Swedish aquaculture has the potential to develop into a green business producing environmentally sustainable healthy food with low...

  10. Applications of probiotic in aquaculture

    OpenAIRE

    Seval Bahadır Koca; Behire Işıl Didinen; Seçil Ekici; Arife Dulluç

    2011-01-01

    Ecological impacts including emergence of a large variety of pathogens and bacterial resistance is caused in increase of productivity in aquaculture. This negatively effects are seen as a results of made applications in production cycles (such as randomly use kemoteropatik). Using probi¬otic in aquaculture is a new approach to reduce these negatively effects. In this study is submi¬ted, definition of the concept probiotic, effect mechanisms of probiotics, colonization to host, selection of pr...

  11. Using an unbaited stationary video system to investigate the behaviour and interactions of bull sharks Carcharhinus leucas under an aquaculture farm

    OpenAIRE

    Loiseau, N.; Kiszka, J. J.; Bouveroux, T.; Heithaus, M. R.; Soria, Marc; Chabanet, Pascale

    2016-01-01

    Bull sharks Carcharhinus leucas are common along the coast of Reunion Island (South-West Indian Ocean) and were suspected to aggregate in the vicinity of an aquaculture farm in Saint-Paul Bay on the west coast. In order to understand the behaviour and interaction of bull sharks near aquaculture cages at Saint-Paul Bay, we deployed an experimental unbaited stationary video camera. From 175 hours of recording during daylight hours from March to April 2012, eight individual female bull sharks (s...

  12. Aquaponics and its potential aquaculture wastewater treatment and human urine treatment

    OpenAIRE

    Sánchez, Henrique Junior Aiveca

    2014-01-01

    The main objective of this thesis is to study the developing fields of aquaponics and its potential for aquaculture wastewater treatment and human urine treatment. Aquaponics is a food production system which combines fish farming (aquaculture) with soilless crop farming (hydroponics). In this thesis the concept of aquaponics and the underlying processes are explained. Research on aquaculture wastewater and human urine wastewater is reviewed and its potential application with aquaponic sys...

  13. A Comparative Economic Evaluation of Farming of three Important Aquaculture Species in Kenya.

    OpenAIRE

    Mbugua, Henry Mwangi

    2007-01-01

    Information on the economic viability of aquaculture is crucial for investors when assessing the feasibility of an aquaculture investment. Unfortunately, such information has been scarce in Kenya. This paper evaluates the viability of commercial culture of three aquaculture species in Kenya under four culture practices. These are: Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus), mainly produced using mono- or polyculture under semi intensive systems; and rainbow ...

  14. Making social sense of aquaculture transitions

    Directory of Open Access Journals (Sweden)

    Simon R. Bush

    2014-09-01

    Full Text Available Resilience deals explicitly with change and provides a middle ground between the social and the environmental sciences. However, a growing critique by social scientists questions the ability of resilience thinking to adequately examine the social dimensions of change. The question that emerges is how social scientists should engage with resilience. We addressed this question by comparing resilience with agrarian change and transitions theory, through the backdrop of the fastest growing global food sector, aquaculture. Our analysis showed that each theoretical perspective provides fundamentally different insights into social and environmental transition inherent in the aquaculture sector. Although resilience thinking is best suited to assessing the ecological aspects of production, its systems ontology limits the inclusion of dynamic social relations or innovation. In contrast, agrarian transition enables a more meaningful understanding of how social relations are reconfigured as agrarian society shifts toward more capitalist modes of production, and transitions theory provides insights into social process of innovation. Given the epistemological differences between these theoretical approaches, we argue against attempts that reify systemic thinking by naturalizing social theories and concepts into resilience thinking. Instead, we argue that social theories such as agrarian change and transition theory should be seen as complimentary and that integration should focus on bridging results and insights. Doing so enables a more robust assessment of the social aspects of social-ecological transitions in the aquaculture sector and beyond.

  15. Kinetics of electro-oxidation of ammonia-N, nitrites and COD from a recirculating aquaculture saline water system using BDD anodes.

    Science.gov (United States)

    Díaz, V; Ibáñez, R; Gómez, P; Urtiaga, A M; Ortiz, I

    2011-01-01

    The viability of the electro-oxidation technology provided with boron doped diamond (BDD) electrodes for the treatment and reuse of the seawater used in a Recirculating Aquaculture System (RAS) was evaluated in this work. The influence of the applied current density (5-50 A m(-2)) in the removal of Total Ammonia Nitrogen (TAN), nitrite and chemical oxygen demand (COD) was analyzed observing that complete TAN removal together with important reductions of the other considered contaminants could be achieved, thus meeting the requirements for reuse of seawater in RAS systems. TAN removal, mainly due to an indirect oxidation mechanism was described by a second order kinetics while COD and nitrite removal followed zero-th order kinetics. The values of the kinetic constants for the anodic oxidation of each compound were obtained as a function of the applied current density (k(TAN) = 7.86 × 10(-5) · exp(6.30 × 10(-2) J); kNO2 = 3.43 × 10(-2) J; k(COD) = 1.35 × 10(-2) J). The formation of free chlorine and oxidation by-products, i.e., trihalomethanes (THMs) was followed along the electro-oxidation process. Although a maximum concentration of 1.7 mg l(-1) of total trihalomethanes was detected an integrated process combining electrochemical oxidation in order to eliminate TAN, nitrite and COD and adsorption onto activated carbon to remove the residual chlorine and THMs is proposed, as an efficient alternative to treat and reuse the seawater in fish culture systems. Finally, the energy consumption of the treatment has been evaluated. PMID:20832837

  16. 鳗鲡循环水养殖系统构建与养殖效果%Constrution and cultured effect of a recirculating aquaculture system for Anguilla

    Institute of Scientific and Technical Information of China (English)

    陈熙春

    2013-01-01

    构建了鳗鲡( Anguilla)循环水养殖系统,该系统由玻璃钢养殖池、生物滤池等关键设施与设备组成。试验分设个体规格为19.60,8.20,2.99 g/尾等3个组,各组放养密度分别为14.92,11.33,9.25 kg/m3。养殖品种为太平洋双色鳗(Anguilla bicolor pacifica),养殖周期为113 d。试验结果显示:各组个体规格达74.99,25.95,7.74 g/尾,各组养殖密度分别达56.89,35.63,23.68 kg/m3,特定生长率分别为1.18,1.02,0.84%/d,饵料系数分别为1.28,1.25,1.42,存活率在98.9%以上。实现水循环利用率84.5%,生产1 kg鳗耗水量约为0.65 m3,单位净产量的电耗与能耗分别为4.69 kW· h/kg和2.01元/kg。结果表明,系统具有节能减排、养殖效果好等优点。%The recirculating aquaculture system for Anguilla constructed of the breeding pool of fiber reinforced plastics and biological aerated filters .The grouper Anguilla bicolor pacifica with an initial boby weight of 19 .6 (A),8.2(B),2.99(C)g were reared in this system at stocking density of 14.92(A),11.33(B),9.25(C) kg/m3 for 113 days.The results showed that the final body weight of 74.99(A),25.95(B) and 7.74(C)g, which the stocking density of 23.68 kg/m3,35.63 kg/m3,56.89 kg/m3, which the specific growth rate(SGR) of 1.18%/d,1.02%/d,0.84%/d, and food conversion rate ( FCR) of 1.28,1.25,1.42 were reached for grouper , and the survival rates were above 98 .9%.The water recycling rate was 84.5% in re-circulating aquaculture system .The water consumption was about 0.65 m3/kg fish in this system .The power consumption and energy consumption of unit net yield was 4.69 kW· h/kg, 2.01 yuan/kg.The results showed that the system has a good property with energy-saving and emission-reductions and better effect of culture .

  17. Wireless Sensor Network Collaborative Monitoring System for Aquaculture Based on Multi-agent System%基于多智能体协同的无线传感网络水产养殖监控系统

    Institute of Scientific and Technical Information of China (English)

    赵明光; 张贤

    2014-01-01

    基于现有监控系统在自学习能力和监控范围方面的局限,将多智能体技术引入到规模化水产养殖监控系统中,提出了一种基于多智能体协同的无线传感网络水产养殖监控系统。系统由信息采集智能体、信息汇聚智能体、环境调节智能体、现场监控智能体和远程监控智能体组成。通过多智能体间的协作,使系统的监控能力得以增强,便于适应多变的养殖环境。试验结果表明,系统能够根据养殖环境因子的变化对养殖环境进行调节,精度满足要求,能够适应规模化水产养殖环境监控的需要。%The existing monitoring system has limitations in self-learning ability and monitoring range.In this paper,the multi-agent technology is introduced into the monitoring and control system for large-scale aquaculture,and a wireless sensor network collaborative monitoring system for aquaculture based on Multi-agent System is proposed.The proposed system consists of infor-mation gathering intelligence agent, information convergence intelligence anent, environment control intelligence agent,field monitoring intelligence agent and remote monitoring intelligence agent.By collaborating among the multi-agents,the monitoring capability of the system is en-hanced and it is easy for the system to get adapted to various breeding environments.The envi-ronment control intelligence agent combines the fuzzy logic and neural network expert system to analyze the data,and realizes the closed loop control process.Test results show that the system can adj ust the breeding environment based on the breeding environment factors,and the adj ust-ment precision can meet the requirements.It can satisfy the needs of large-scale aquaculture envi-ronment monitoring.

  18. 工厂化水产养殖 LED 灯具选择的分析与建议%The Analysis and Suggestion of LED Lamp Selection in Industial Aquaculture Systems

    Institute of Scientific and Technical Information of China (English)

    宋昌斌; 高霄龙; 仇登高; 刘鹰; 王朝夕; 谢海忠; 杨华; 姚然; 王军喜

    2015-01-01

    This paper illustrates the importance of the LED light source in the recirculating aquaculture systems, introducing the current status of lighting in aquaculture workshop, and providing some useful analysis and suggestions in accordance with the required principle of three light environment parameters in fish and the requirements of lamps in specific contexts, which would be instructive and meaningful to how to choose the suitable LED lamps in aquaculture workshop.%阐述了LED光源对循环水养殖系统的重要性,介绍了养殖车间光照的现状,并根据鱼类对光环境三要素一般的适应需求规律、针对灯具在特定使用环境下的要求进行了分析与建议,对水产养殖车间如何正确选择LED灯具具有指导意义。

  19. Survey of Electronic Payment Methods and Systems

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Smit, Gerard J.M.; Helme, Arne

    1996-01-01

    In this paper an overview of electronic payment methods and systems is given. This survey is done as part of the Moby Dick project. Electronic payment systems can be grouped into three broad classes: traditional money transactions, digital currency and creditdebit payments. Such payment systems have

  20. Potential use of power plant reject heat in commercial aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.

    1977-01-01

    Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10/sup 5/ kg/year of fish, 1.5 x 10/sup 6/ kg/year of clam meat, and 1.5 x 10/sup 4/ kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated.

  1. Issues, impacts, and implications of shrimp aquaculture in Thailand

    Science.gov (United States)

    Dierberg, Forrest E.; Kiattisimkul, Woraphan

    1996-09-01

    Water quality impacts to and from intensive shrimp aquaculture in Thailand are substantial. Besides the surface and subsurface salinization of freshwaters, loadings of solids, oxygen-consuming organic matter, and nutrients to receiving waters are considerable when the cumulative impacts from water exchange during the growout cycle, pond drainage during harvesting, and illegal pond sediment disposal are taken into account. Although just beginning to be considered in Thailand, partial recirculating and integrated intensive farming systems are producing promising, if somewhat limited, results. By providing on-site treatment of the effluent from the shrimp growout ponds, there is less reliance on using outside water supplies, believed to be the source of the contamination. The explosion in the number of intensively operated shrimp farms has not only impacted the coastal zone of Thailand, but has also resulted in an unsustainable aquaculture industry. Abandonment of shrimp ponds due to either drastic, disease-caused collapses or more grandual, year-to-year reductions in the productivity of the pond is common. To move Thailand towards a more sustainable aquaculture industry and coastal zone environment, integrated aquaculture management is needed. Components of integrated aquaculture management are technical and institutional. The technical components involve deployment of wastewater treatment and minimal water-use systems aimed at making aquaculture operations more hydraulically closed. Before this is possible, technical and economic feasibility studies on enhanced nitrification systems and organic solids removal by oxidation between production cycles and/or the utilization of plastic pond liners need to be conducted. The integration of semi-intensive aquaculture within mangrove areas also should be investigated since mangrove losses attributable to shrimp aquaculture are estimated to be between 16 and 32% of the total mangrove area destroyed betweeen 1979 and 1993

  2. Ecosystem-based approach to aquaculture management

    Directory of Open Access Journals (Sweden)

    Patrick White

    2008-12-01

    Full Text Available Ecosystems have real thresholds and limits which, when exceeded, can affect major system restructuring. Once thresholds and limits have been exceeded, changes can be irreversible. Diversity is important to ecosystem functioning. The ecosystem approach is a strategy for the integrated management of land, water, and living resources that promotes conservation and sustainable use in an equitable way. The application of the ecosystem approach will help to reach a balance of the three main objectives: conservation, sustainable use, and a fair and equitable sharing of the benefits and use of the natural resources. Aquaculture development needs to be within the carrying capacity of the water resource so that it is sustainable and does not greatly impact the environment. The determination of the carrying capacity needs to be science-based. The planning of development in ecosystems has been done for freshwater ecosystems within the PAMB (Protected Area Management Board framework, but in many cases this does not give the correct significance to the impact of aquaculture on the water resources in the ecosystem. It also needs to be extended to river basins and estuaries, brackishwater areas, and inland bays, and seas. The planning and management of aquaculture needs to be undertaken at the local government unit (LGU level in a coordinated manner by all the LGUs that have a part of the water resource. The co-management of aquaculture, in terms of monitoring of the environment, monitoring of production, and monitoring of licenses, needs to be funded out of license fees and non-compliance fines collected by the LGUs. A number of these management activities need to be undertaken jointly (monitoring the environment and others separately but in a coordinated manner (e.g., checking licenses and checking compliance.

  3. Multipurpose Platform for Electronic Currency System

    Directory of Open Access Journals (Sweden)

    Andreea Magdalena Dae

    2014-12-01

    Full Text Available Nowadays, there are multiple solutions for exchanging electronic currencies which will most probably replace physical money. This paper presents a platform for electronic currency system implemented within a Java smart card for accessing different types of products or services. The user interacts with an “electronic currency bank” and with a merchant through a secure protocol.

  4. Electronic Official Personnel Folder System

    Data.gov (United States)

    US Agency for International Development — The eOPF is a digital recreation of paper personnel folder that stores electronic personnel data spanning an individual's Federal career. eOPF allows employees to...

  5. Understanding electronic systems in semiconductor quantum dots

    Science.gov (United States)

    Ciftja, Orion

    2013-11-01

    Systems of confined electrons are found everywhere in nature in the form of atoms where the orbiting electrons are confined by the Coulomb attraction of the nucleus. Advancement of nanotechnology has, however, provided us with an alternative way to confine electrons by using artificial confining potentials. A typical structure of this nature is the quantum dot, a nanoscale system which consists of few confined electrons. There are many types of quantum dots ranging from self-assembled to miniaturized semiconductor quantum dots. In this work we are interested in electrostatically confined semiconductor quantum dot systems where the electrostatic confining potential that traps the electrons is generated by external electrodes, doping, strain or other factors. A large number of semiconductor quantum dots of this type are fabricated by applying lithographically patterned gate electrodes or by etching on two-dimensional electron gases in semiconductor heterostructures. Because of this, the whole structure can be treated as a confined two-dimensional electron system. Quantum confinement profoundly affects the way in which electrons interact with each other, and external parameters such as a magnetic field. Since a magnetic field affects both the orbital and the spin motion of the electrons, the interplay between quantum confinement, electron-electron correlation effects and the magnetic field gives rise to very interesting physical phenomena. Thus, confined systems of electrons in a semiconductor quantum dot represent a unique opportunity to study fundamental quantum theories in a controllable atomic-like setup. In this work, we describe some common theoretical models which are used to study confined systems of electrons in a two-dimensional semiconductor quantum dot. The main emphasis of the work is to draw attention to important physical phenomena that arise in confined two-dimensional electron systems under various quantum regimes.

  6. Nutrition of aquaculture species.

    Science.gov (United States)

    Lovell, R T

    1991-10-01

    Dietary requirements for amino acids and fatty acids have been reported for channel catfish (Ictalurus punctatus), salmonids (Oncorhynchus spp.), common carp (Cyprinus carpio), tilapias (Oreochromis spp.), and eel (Anguilla japonicus). Most of the vitamin and mineral requirements are available for channel catfish and salmonids, and some are available for common carp, tilapia, eel, and other finfish and crustaceans. From this available information, cost-effective feeds can be formulated for the major commercial aquaculture species. Major differences in nutrient requirements between fish and mammals or birds are as follows: fish have a lower digestible energy:protein ratio (8 to 10 kcal of DE/g of CP for fish vs 15 to 20 kcal of DE/g of CP for livestock); fish require n-3 fatty acids and land animals require n-6; fish can absorb minerals from the water, which negates the need for some minerals in the diet; and fish have limited ability to synthesize vitamin C and must depend on a dietary source. Areas for further research include 1) refinement of nutrient requirements of the major culture species considering effects of fish size, temperature, and management; 2) nutrient requirements of crustaceans; 3) effects of nutrition on fish health and product quality; and 4) feeding technology. PMID:1778835

  7. Thalassotalea marina sp. nov., isolated from a marine recirculating aquaculture system, reclassification of Thalassomonas eurytherma as Thalassotalea eurytherma comb. nov. and emended description of the genus Thalassotalea.

    Science.gov (United States)

    Hou, Ting-Ting; Liu, Ying; Zhong, Zhi-Ping; Liu, Hong-Can; Liu, Zhi-Pei

    2015-12-01

    A Gram-stain-negative, facultatively anaerobic bacterium, strain QBLM2T, was isolated from rearing water of a marine recirculating aquaculture system in Tianjin, China. Its taxonomic position was investigated through a polyphasic approach. Cells of strain QBLM2T were non-spore-forming rods, motile by means of a single polar flagellum. Positive for oxidase and catalase. Growth occurred at 15-40 °C (optimum 30 °C), at pH 6.5-10.5 (optimum pH 7.5-8.5) and in the presence of 0-5.0 % (w/v) NaCl (optimum 3 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QBLM2T formed a distinct lineage within the genus Thalassotalea and exhibited sequence similarities of 94.5-96.3 % to members of the genus Thalassotalea. The predominant fatty acids (>10 %) were C17 : 1ω8c and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The major polar lipids were phosphatidylglycerol and phosphatidylethanolamine. Ubiquinone 8 (Q-8) was the major ubiquinone. The DNA G+C content was 37.1 mol%. Based on the data above, strain QBLM2T is considered to represent a novel species of the genus Thalassotalea, for which the name Thalassotalea marina sp. nov. is proposed. The type strain is QBLM2T ( = CGMCC 1.12814T = KCTC 42731T). Phylogenetic analyses indicated that Thalassomonas eurytherma Za6a-12T fell within the genus Thalassotalea, so it is reclassified as Thalassotalea eurytherma comb. nov. and the description of the genus Thalassotalea is emended. PMID:26400666

  8. 循环水养殖系统中的固体悬浮物去除技术%Suspended solids removal technology in recirculating aquaculture systems

    Institute of Scientific and Technical Information of China (English)

    倪琦; 张宇雷

    2007-01-01

    循环水养殖系统(Recirculating aquaculture systems,RAS)中固体悬浮物(Suspended solids,SS)的去除效果直接影响到鱼类生长、生物净化效果、系统配置和运行成本等诸多重要因子.根据固体悬浮物产生、物理特性和分布规律,结合颗粒悬浮物去除工艺特点,对去除技术进行系统研究分析.固体悬浮物源自饲料,密度一般为1.05~1.19 g/cm3,运用重力分离、过滤和泡沫分离等工艺通过预处理、粗过滤和精处理三道工艺步骤,可分别去除不同直径的颗粒物质,在达到合理含量的前提下,获得低能耗、低成本和系统稳定运行的综合效果.固体悬浮物的去除符合目标明确、排出及时和区别对待三原则,去除工艺注重相关技术的优化集成.

  9. Performance of shrimp recirculating aquaculture system with copper polluted water%Cu污染条件下封闭循环水养虾系统的效能

    Institute of Scientific and Technical Information of China (English)

    程波; 刘鹰; 杨红生; 高喜燕

    2011-01-01

    The disease outbreaks, environmental degradation and poor management practice are the major problems to the shrimp aquaculture industry in recent years.With the developing of engineering, aeration and the high quality of artificial feeds, shrimp culture in a recirculating aquaculture system (RA.S) becomes an environmentally and economically sustainable method to solve those problems.But the copper pollution has been a big problem in the coasts of China as a result of the developing of industry, and the shrimp cultures also use copper sulfate frequently to eradicate algae during Litopenaeus vannamei culturing.An experiment was conducted for intensive culture of shrimp (L.vannamei) in RAS for a period of three months to concentrate on the performance of the biofilter and the food safety under the copper polluted water (0.3 mg/L).The results indicated that there was no significant difference in the removal rate on COD, NH4-N and NO2-N and the number of heterotrophic bacteria, ammonium-oxidizing bacteria and nitrite-oxidizing bacteria in the biofilm as the Cu2+ concentration decreased to (0.089±0.012) mg/L at the harvest.No significant difference was found between treatments concerning the feed conversion ratio (FCR), the mortality rate and the yield.The accumulated concentration of Cu2+ in the shrimp at last was (29.36±4.06) mg/kg and (42.91±6.10) mg/kg in the control and treated RAS respectively, but it was in the range of national security standards of the green food and pollution-free agriculture products.The study suggests that the RAS can work well and supply safety food shrimp under 0.3 mg/L copper pollution in three month culturing period.%为获得Cu2+污染对封闭循环水养虾系统的影响,选用0.3 mg/L Cu2+浓度,研究其对系统中水质、对虾生长、存活及生物滤器水处理效能的影响.结果表明,经过84 d的试验,养殖水体中Cu2+质量浓度在系统水处理单元作用下降为(0.089±0.012)mg/L,

  10. RESEARCHES REGARDING THE TECHNOLOGICAL PERFORMANCES OF CARP REARING DURING WINTER PERIOD IN THE CONDITIONS OF A RECIRCULATING AQUACULTURE SYSTEM

    OpenAIRE

    G. STEFAN; Cristea, V.; A. MIHALACHE; Grecu, I.; I. VASILEAN; L. SFETCU; Gheorghe, D.; A. DOCAN

    2013-01-01

    The techniques of carp culture are highly diversified, ranging from the extensive production in pond or open water with no fertilization or supplemental feeding to highly intensive systems in concrete tanks or cages. Among the different carp species, common carp is the best species reared in intensive monoculture, the others (Chinese and Indian carps) being usually cultivated in polyculture (P. Kestemont, 1995). An experiment was conducted in inside recirculation system conditions to identify...

  11. 环境因子对循环水养殖系统中生物膜净化效率影响综述%Progress of research on environmental factors affecting biofilter efficiency in recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    杨志强; 朱建新; 刘慧; 程海华; 曲克明; 刘寿堂

    2014-01-01

    循环水养殖系统的关键技术是养殖废水的处理和再利用。作为循环水养殖系统水处理的核心单元,生物膜对于养殖水体中污染物的去除起着至关重要的作用。水温、盐度、pH和溶氧等环境因子都会影响生物膜的功能,环境因子的突然变化会引起生物膜脱落、影响循环水养殖系统生物膜的形成过程及运行效果。控制好水温、盐度、pH和溶氧,生物膜净化效率就能达到较为理想的状态,养殖废水的处理效果就会更好。因此,有必要研究各个环境因子变量条件下的养殖废水去除动力学特征,以期为循环水养殖系统优化设计与运行管理提供理论依据。%Treatment and reuse of aquaculture wastewater is the key technology in recirculating aquaculture systems (RAS). Biofilter, a core unit in RAS, plays a vital role in removal of pollutants in aquaculture water. Water temperature, salinity, pH, dissolved oxygen ( DO ) and other environmental factors can affect the function of biofilter. Sudden changes of environmental factors can cause biofilm degradation or dropping off, which may seriously affect biofilter growth and water treatment effects. Biofilter efficiency can achieve the ideal state and aquaculture wastewater treatment effect be improved when the water temperature, salinity, pH and DO are well under control. It is necessary to study biofilter’ s kinetics of aquaculture wastes removal under each environmental factor, so as to provide a theoretical basis for optimizing design and operation management of RAS.

  12. Reliability of power electronic converter systems

    CERN Document Server

    Chung, Henry Shu-hung; Blaabjerg, Frede; Pecht, Michael

    2016-01-01

    This book outlines current research into the scientific modeling, experimentation, and remedial measures for advancing the reliability, availability, system robustness, and maintainability of Power Electronic Converter Systems (PECS) at different levels of complexity.

  13. Electronic Resource Management Systems in Practice

    Science.gov (United States)

    Grogg, Jill E.

    2008-01-01

    Electronic resource management (ERM) systems have inundated the library marketplace. Both integrated library systems (ILS) vendors and subscription agents are now offering products and service enhancements that claim to help libraries efficiently manage their electronic resources. Additionally, some homegrown and open-source solutions have emerged…

  14. Electronic Money: A Viable Payment System?

    OpenAIRE

    Guadamuz, Andres

    2003-01-01

    This paper explores some of the legal and practical issues related to the implementation of electronic money placed in smart cards as a viable online payment system. This is a subject of particular importance as many there are many hopes from the financial industry about the implementation of an electronic currency system will create a great method for small transactions, both online and offline.

  15. High perveance electron gun for the electron cooling system

    International Nuclear Information System (INIS)

    The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 μA/V3/2, Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual)

  16. High perveance electron gun for the electron cooling system

    Science.gov (United States)

    Korotaev, Yu; Meshkov, I.; Petrov, A.; Sidorin, A.; Smirnov, A.; Syresin, E.; Titkova, I.

    2000-02-01

    The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 μA/ V3/2, Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual).

  17. High perveance electron gun for the electron cooling system

    CERN Document Server

    Korotaev, Yu V; Petrov, A; Sidorin, A; Smirnov, A; Syresin, E M; Titkova, I

    2000-01-01

    The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 mu A/V sup 3 sup / sup 2 , Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual).

  18. Anonymity control in electronic check systems

    Institute of Scientific and Technical Information of China (English)

    Ma Chunguang; Yang Yixian; Hu Zhengming

    2005-01-01

    Electronic check systems, as one of electronic payment systems, are more desirable than other electronic cash systems. In the system, only a single check is used to pay any price that is not more than the face value. The main problem in check systems is to design an efficient refund mechanism that makes refund checks undistinguished from initial checks during payment and deposit. The problem of anonymity control also called fairness is also an important issue in check systems. All check systems yet are unconditional anonymity that opens the door to misuse for crime such as laundering and blackmailing. In this paper, the notion of anonymity revocation is introduced to electronic check system for the first time, and a model of fair electronic check system is proposed. An efficient fair online electronic check system with reusable refund is presented. In the system, a passive trustee is employed to revoke the anonymity of un-honest users. Moreover, the system solves the reusability problem of refunds thanks to the RSA-based partially signature. The system is efficient and meets all basic security requirements.

  19. 水产养殖过程水质模糊综合评价系统的设计%The Fuzzy Comprehensive Evaluation System Design of Aquaculture Process Water Quality

    Institute of Scientific and Technical Information of China (English)

    马从国; 赵德安

    2011-01-01

    Taking water quality of aquaculture pond as study object, the evaluation system and evaluation criteria of pond water quality were proposed and the fuzzy comprehensive evaluation model was set up and the fuzzy comprehensive evaluation system of pond water were designed and implemented based on the comprehensive analysis of the impact factors. The system was applied into the enterprise evaluation of aquaculture pond water quality, and good results were achieved. Many experimental results showed that the fuzzy comprehensive evaluation system can gain the reasonable and objective evaluation results of fishery water quality. It was easy to use the system and it can improve the economic and social benefits of the aquaculture industry.%以池塘水产养殖水质为研究对象,在综合分析池塘水质各影响因子的基础上,提出了水质评价指标体系和评价标准,建立了渔业水质模糊综合评价模型,设计和实现了池塘养殖水质模糊综合评价系统.将该系统应用于某企业养殖池塘水质的评价,取得了较好效果.大量试验结果表明,该模糊综合评价系统对渔业水质的综合评价结果客观、合理,使用简便,提高了水产养殖业的经济和社会效益.

  20. 基于STELLA的循环水养殖系统池塘总氨氮动态模拟%Dynamic Simulation of Total Ammonia in Culture Ponds of Recirculating Aquaculture System Based on STELLA Model

    Institute of Scientific and Technical Information of China (English)

    于涛; 钟非; 贺锋; 梁威; 吴振斌

    2013-01-01

    A theoretical model to evaluate total ammonia concentration in recirculating aquaculture system was established by investigating the relationship between impact factors of total ammonia.Subsequently,a system dynamics model for total ammonia in the recirculating aquaculture system was developed based on the theoretical model.The dynamics of total ammonia concentration in a culture pond during the breeding process was simulated by using STELLA simulation software.The simulation results were consistent with the measured values approximately,indicating that this model could simulate the experimental system to a certain extent and could provide suggestions on design and operation of the recirculating aquaculture system.%通过对影响循环水养殖系统养殖池塘中总氨氮动态的各种因素及其因果关系的分析,得出了养殖池塘中总氨氮的理论模型.在理论模型基础上,使用STELLA系统动力学模拟软件建立了循环水养殖实验系统中池塘水体总氨氮的系统动力学模型.通过将系统设计和运行的相关参数代人到该模型中,对养殖过程中池塘中总氨氮的动态变化进行了模拟运算,模拟结果与实测值基本吻合,说明该模型对实验系统的模拟具有一定的可信度,可为循环水养殖系统的设计和运行优化提供依据.

  1. Improving productivity, efficiency, product quality and environmental sustainability of aquaculture operations through systemic integration of information and knowledge

    Science.gov (United States)

    Experts on selective breeding, physiology, genomics and bioinformatics will present and discuss state of the art information and relevant examples from fish and other animal systems. Identify strategies that will foster continuous improvements in experimental design and data gathering, analysis, be...

  2. Use of recirculating aquaculture systems to increase production and quality of hatchery reared juvenile red drum for marine stock enhancement

    Science.gov (United States)

    The abundance of economically important marine sportfish has declined in Florida’s waters due to factors such as over-fishing and critical habitat disturbance. Hatchery production and enhancement stocking has traditionally been used in freshwater systems as a means of mitigating for effects such as ...

  3. Performance evaluation of four different methods for circulating water in commercial-scale, split-pond aquaculture systems

    Science.gov (United States)

    The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two conveyance structures. Water is circulated between the two basins with high-volume pumps and many different pumping systems are being used on commercial farms. Pump performance was evaluated with fou...

  4. World aquaculture: environmental impacts and troubleshooting alternatives.

    Science.gov (United States)

    Martinez-Porchas, Marcel; Martinez-Cordova, Luis R

    2012-01-01

    Aquaculture has been considered as an option to cope with the world food demand. However, criticisms have arisen around aquaculture, most of them related to the destruction of ecosystems such as mangrove forest to construct aquaculture farms, as well as the environmental impacts of the effluents on the receiving ecosystems. The inherent benefits of aquaculture such as massive food production and economical profits have led the scientific community to seek for diverse strategies to minimize the negative impacts, rather than just prohibiting the activity. Aquaculture is a possible panacea, but at present is also responsible for diverse problems related with the environmental health; however the new strategies proposed during the last decade have proven that it is possible to achieve a sustainable aquaculture, but such strategies should be supported and proclaimed by the different federal environmental agencies from all countries. Additionally there is an urgent need to improve legislation and regulation for aquaculture. Only under such scenario, aquaculture will be a sustainable practice.

  5. Improvement of Aquaculture Water Quality Monitoring System by Information Fusion Technology%用信息融合技术改进水产养殖水质监控系统

    Institute of Scientific and Technical Information of China (English)

    毛力; 肖炜; 杨弘

    2015-01-01

    水质监控是实现水产养殖现代化的关键因素之一。本文设计并实现了一种基于物联网技术的水产养殖水质监控系统。该系统将传感及传感网技术、ZigBee/GPRS/3G 技术和信息融合与数据挖掘等物联网技术引入到水产养殖水质监控系统。目前该系统在国家罗非鱼产业技术研发中心无锡育种和保种基地平稳地运行,节能降耗、绿色环保,预测预警准确性较高,减少了各类灾害事故的发生,提高了水产品的品质,可在水产养殖水质监控中推广应用。%Water quality monitoring is one of the key factors to realize the modernization of aquaculture. An aquaculture water quality monitoring system was designed and implemented based on internet of things technology system sensor and sensor network technolo-gy, which ZigBee/GPRS/3G technology, information fusion and data mining technology were taken into the aquaculture water quality monitoring system. The system was applied to a tilapia breeding base on the modern agriculture industrial technology system in Wuxi, with smooth working and relatively high forecasting accuracy. The findings indicated that the system led to great improvement of prod-uct and water quality and energy utilization, to reduction in occurrence of various types of disasters and accidents, and to environmen-tal protection, which can be widely applied in the field of aquaculture water quality monitoring.

  6. Grid type culture of Portunus trituberculatus in a recirculating aquaculture system%梭子蟹格栅式循环水养殖技术

    Institute of Scientific and Technical Information of China (English)

    许程林; 赵永超; 陈玉生; 吉红九; 贲成恺; 钟非

    2015-01-01

    Traditional Portunus trituberculatusculture in pond , isolated net, cage and basket are subject to the natural environment and are characterized by poor controllability, great labor intensity, low yield.In this study, a grid type culture of P.trituberculatus in a recirculating aquaculture system was explored, which have advantages of avoiding cannibolism, sunshade and heat preservation, aeration and decontamination.Crabs at stage of C8-C9 were moved into the grid type recirculating culture system and cultured for 113 days to commercial crab at stage of C11-C12 , the carapace breadth and body weight reached to 168 mm and 253 g respectively.And the average yield reached to 3.054 kg/m2 with survival rate of 75.4%.Compared to the traditional culture model, the average yield of grid type recirculating culture system has significantly increased.%传统的梭子蟹池塘养殖、围网养殖以及后来发展的笼养、筐养等对自然环境依赖性强、可控性差、劳动强度大、养殖产量低。本研究针对传统养殖方式的不足,采用格栅式单体养殖方法,有机组合生物净化水处理单元,构建了温室大棚梭子蟹格栅式循环水养殖系统,研发了具有“防止互残、遮阳保温、增氧去污”等性能的梭子蟹养殖新模式。结果表明,格栅式养殖池放养梭子蟹C8~C9期大规格苗种,经113 d养成至C11~C12期商品蟹,平均甲宽168 mm、平均体重253 g,存活率75.4%,养殖平均产量3.054 kg/m2。与传统养殖方式相比,采用温室大棚格栅式循环水养殖技术能有效延长梭子蟹的生长期,单位面积养殖产量和存活率均有显著提高。

  7. World Aquaculture: Environmental Impacts and Troubleshooting Alternatives

    OpenAIRE

    Marcel Martinez-Porchas; Martinez-Cordova, Luis R.

    2012-01-01

    Aquaculture has been considered as an option to cope with the world food demand. However, criticisms have arisen around aquaculture, most of them related to the destruction of ecosystems such as mangrove forest to construct aquaculture farms, as well as the environmental impacts of the effluents on the receiving ecosystems. The inherent benefits of aquaculture such as massive food production and economical profits have led the scientific community to seek for diverse strategies to minimize th...

  8. Mediterranean Aquaculture: Marine Fish Farming Development

    OpenAIRE

    Basurco, B.

    2001-01-01

    in many parts of the world, aquaculture production in the Mediterranean has been expanding rapidly over recent years. Total aquaculture production in the region reached 1,266,959 t in 1999, which represents approximately 6% of the world aquaculture production (3% in 1995). Although Mediterranean aquaculture still focuses more on mollusc production (53.9%), the share of fish production is progressing constantly (46% in 1999, and 35% in 1995), parallel to global trends of world a...

  9. Knowing Asian aquaculture and fisheries. Part 1

    OpenAIRE

    Surtida, M.B.

    1998-01-01

    An outline is given of aquaculture and fisheries in Asia, providing information of use to students whose work can influence laws, rules, policy and regulations on aquaculture and fisheries, with the view in mind to sustainable aquaculture. In this issue, the following countries are examined: China, Indonesia, and Bangladesh.

  10. Increased competition for aquaculture from fisheries

    DEFF Research Database (Denmark)

    Jensen, Frank; Nielsen, Max; Nielsen, Rasmus

    2014-01-01

    ; and supplies from aquaculture have grown continuously. In this paper, the impact of improved fisheries management on aquaculture growth is studied assuming perfect substitution between farmed and wild fish. We find that improved fisheries management, ceteris paribus, reduces the growth potential of global...... aquaculture in markets where wild fisheries constitute a large share of total supply....

  11. Design of Aquaculture Environment Monitoring System Based on ZigBee Technology%基于ZigBee技术的水产养殖环境监测系统设计

    Institute of Scientific and Technical Information of China (English)

    刘玉梅; 张长利; 王树文; 李正仁

    2011-01-01

    传统的水产养殖手段科技储备不足,浪费了人量的人力和物力.本文采用目前无线传感器网络界士流的ZigBee技术,结合GPRS通讯技术,以及网络数据库技术,设计完成了一套完整的水产养殖环境监测系统,对影响鱼类生长的温度,溶解氧含量、PH值等水环境因素进行实时数据采集监测.系统由无线传感器网络节点和网络管理平台两部分组成,设计了良好的人机交换界面.实验表明该系统能实现对水产养殖环境的实时监测,能满足目前水产养殖自动化和统一管理的需求.%The traditional aquiculture means is lack of technology of advantages, wasting a great deal of manpower and material.This paper adopts mainstream ZigBee technology in wireless sensor network field, combined with GPRS communication technology and network database technology, a set of aquaculture environment monitoring system is designed and completed, for the factors such as the growth of fish temperature, oxygen content, PH value of water environment, realtime data acquisition and monitoring are adopted. The system consists of wireless sensor network node and network management platform, designing a good man-computer exchange interface. Through commissioning in the test experiments,the system can realize real-time monitoring to the aquaculture environment, can satisfy the present requirements for aquaculture automation and unified management.

  12. Status of Irish Aquaculture 2004

    OpenAIRE

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2005-01-01

    This report is the second annual report on the status of Irish aquaculture (see Parsons et al., 2004). It has been produced in collaboration with the three main State agencies that provide support services in the areas of research and development to the industry – Bord Iascaigh Mhara (BIM), the Marine Institute and Taighde Mara. The aims of the report are to: (1) provide an objective and comprehensive source of information on the status of Irish aquaculture in 2004; (2) show the main trends i...

  13. Applications of probiotic in aquaculture

    Directory of Open Access Journals (Sweden)

    Seval Bahadır Koca

    2011-10-01

    Full Text Available Ecological impacts including emergence of a large variety of pathogens and bacterial resistance is caused in increase of productivity in aquaculture. This negatively effects are seen as a results of made applications in production cycles (such as randomly use kemoteropatik. Using probi¬otic in aquaculture is a new approach to reduce these negatively effects. In this study is submi¬ted, definition of the concept probiotic, effect mechanisms of probiotics, colonization to host, selection of probiotics, use probiotic in fish, crustacean, the mollusk and the live feed.

  14. A simple electron-beam lithography system

    DEFF Research Database (Denmark)

    Mølhave, Kristian; Madsen, Dorte Nørgaard; Bøggild, Peter

    2005-01-01

    of the column of a scanning electron microscope (SEM). The system can easily be mounted on most standard SEM systems. The tested setup allows an area of up to about 50 x 50 pm to be scanned, if the upper limit for acceptable reduction of the SEM resolution is set to 10 run. We demonstrate how the EBL system can...... be used to write three-dimensional nanostructures by electron-beam deposition. (C) 2004 Elsevier B.V. All rights reserved....

  15. An Electronic System for Home Care Protocols

    OpenAIRE

    Saba, Virginia K.; Irwin, Ruth Galten

    2001-01-01

    This is demonstration of an Electronic Tracking System being implemented in several Home Health Agencies in the US. It uses the Home Health Care Classification (HHCC) System, a standardized terminology designed and developed to document patient care. The goal it to take the coded data to design the Electronic Tracking System as a method for predicting resource requirements, tracking care needs, and measuring the outcomes of the care.

  16. The effect of density in larval rearing of the pullet carpet shell Venerupis corrugata (Gmelin, 1791) in a recirculating aquaculture system

    OpenAIRE

    Joaquim, S.; Matias, D.; A Matias; Leitão, A; Soares, F.; Cabral, M.; Chícharo, L.; Gaspar, M.B.

    2014-01-01

    The pullet carpet shell Venerupis corrugata is an economically valuable species in several European countries, however, nowadays stocks are under high fishing pressure. Hatchery production of juveniles for release is a major contributor to strengthen the stock and consequently improve the sustainability of the natural stocks. This study aimed to determine the feasibility of rearing V. corrugata larvae with different larval densities (10, 40 and 200 larvae per mL) in a recirculating aquacultur...

  17. Ecotoxicity assessment in aquaculture system using the test organism Pseudokirchneriella subcapitata (Chlorophyceae) - doi: 10.4025/actascibiolsci.v34i4.9391

    OpenAIRE

    Julio Vicente Lombardi; Luciana Miashiro; Cacilda Thais Janson Mercante

    2012-01-01

    The purpose of this study is to perform toxicity tests with microalgae Pseudokirchneriella subcapitata (Chlorophyceae) using inland water samples to evaluate the impact caused by aquaculture. Six field samples were collected ranged November 2006 to March 2007, at Experimental Station, Pindamonhangaba, State of São Paulo. Abiotic factors pointed out to the mesotrophic and eutrophic characteristics already observed at the fish pond and its effluent. The results of ecotoxicological tests carried...

  18. Corrosion Reliability of Electronic Systems

    DEFF Research Database (Denmark)

    Ambat, Rajan; Jensen, Stine G.; Møller, Per

    2008-01-01

    Inherently two factors namely multi-material usage and potential bias makes electronic devices susceptible to corrosion if exposed to humid conditions. The problem is compounded today due to miniaturization and contamination effects. The reduction in size of the components and close spacing...... on a Printed Circuit Board (PCB) for high density packing has greatly increased the risk of corrosion under humid conditions. An important issue is the failures due to electrolytic metal migration. This paper describes an investigation of the electrolytic migration of Sn-Pb solder lines on PCBs in humid...

  19. HIRFL-CSR electron cooling system

    International Nuclear Information System (INIS)

    Electron cooling technique will be applied to the proposed Lanzhou heavy ion cooler-storage ring (HIRFL-CSR). A electron cooling device with a maximum electron energy of 165 keV and maximum current density of 0.244 A/cm2 is planned to cool heavy ions up to energies of 300 MeV/u. The preliminary design for the cooling system is presented

  20. Pilot scale study on water quality variation characteristics of recirculating aquaculture system%循环水养殖系统水质变化特征的中试研究

    Institute of Scientific and Technical Information of China (English)

    郭浩; 马伟芳; 韩东梅; 陈国伟; 王筱雯

    2012-01-01

    A recirculating aquaculture system on rainbow trout,sturgeon and chub multistep aquaculture was used in the pilot scale study.Without changing fresh water,the system continuously run for 30 days,the variation characrastics of COD,NH+4-N and TP were analyzed.The results indicated that,with the same aquaculture density,COD,NH+4-N and TP increased by 26.6%,45.7% and 37.4%,respectively in rainbow trout aquaculture part.COD,NH+4-N and TP increased by 16.0%,21.6% and 14.4%,respectively in sturgeon aquaculture part.The removal rates of COD,NH+4-N and TP were 39.8%,50.0% and 1.9%,resprectively in biofilter.The chub aquaculture part and aquatic plant sedimentation basin were also added in the system,with the purpose of increasing the contaminant removal efficiency.In 21 days later,with adding chitosan in sedimentation basin,the turbidity and chroma reduced to 46.6% and 38.0%,respectively.With 30 days continuously running,both COD and NH+4-N achieved the Ⅲ level of GB 3838-2002,excepted TP.%采用循环水养殖系统进行虹鳟、鲟鱼和鲢鱼的阶梯养殖中试研究,在不更换新鲜水的情况下,系统连续运行30天,分析其中COD、NH4+-N和TP的变化特征。结果表明,在相同养殖密度情况下,养殖虹鳟鱼使循环水COD、NH4+-N和TP浓度分别增加26.6%、45.7%和37.4%,养殖鲟鱼使COD、NH4+-N和TP浓度分别增加16.0%、21.6%和14.4%,生化池对COD、NH4+-N和TP的去除率分别为39.8%、50.0%和1.9%。系统还加入了鲢鱼养殖单元和配置水生植物的沉淀池,增加了系统对污染物的去除效果。实验自第21天起向沉淀池投加壳聚糖,使循环水浊度降低了46.6%,色度降低了38.0%。经过30 d的连续运行,除TP指标外,COD和NH4+-N浓度仍满足《地表水环境质量标准》(GB3838-2002)中地表水Ⅲ类功能区用水标准。

  1. Water treatment processes in marine recirculating aquaculture systems: A review%海水循环养殖系统水处理工艺综述

    Institute of Scientific and Technical Information of China (English)

    姜妍君; 强志民; 董慧峪; 贲伟伟; 王磊

    2013-01-01

    This paper reviews the key water quality parameters and the related unit treatment processes in marine recirculating aquaculture systems ( RAS). Besides routinely monitoring and controlling salinity, pH, temperature, and dissolved oxygen, RAS usually adopts physical, chemical and biological combinational treatment processes to reduce the concentrations of solid particles, ammonia nitrogen, nitrite, nitrate, organic matter and pathogens. Solid particles can be removed by sedimentation, filtration, foam fractionation or biofiltration according to different particle sizes and settlabilities. Ammonia nitrogen, nitrite and nitrate are mainly removed by biological nitrification and denitrification. Organic matter can be decomposed by microorganisms. Chemical oxidants and ultraviolet radiation are commonly-used disinfection methods in RAS. Disinfectant residue and disinfection byproducts, two critical factors impacting water quality and animal health, should be primarily concerned when selecting appropriate disinfection method. Finally, several commonly-adopted combinational treatment processes for RAS are exemplified with suggestions for future improvement provided.%论述了海水循环养殖系统(RAS)需要控制的水质参数及相关单元水处理工艺.RAS需要对盐度、pH、温度、溶解氧等水质参数进行监测控制,并常采用物理、生物、化学处理的组合工艺,使固体物质、氨氮、亚硝酸盐、硝酸盐、有机物以及致病微生物等的浓度维持在安全范围内.固体物质根据粒径和可沉降性的不同,可采用沉降、过滤、泡沫分离或生物过滤法去除;氨氮、亚硝酸盐以及硝酸盐主要通过生物的硝化和反硝化作用去除;有机物主要通过生物降解去除;化学药剂消毒以及紫外辐照是RAS常用的消毒方法,消毒剂残余及消毒副产物对水质和动物健康的影响是选择合适消毒方法需要考虑的两个关键因素.最后,列举了几种海

  2. Electronic Dental Records System Adoption.

    Science.gov (United States)

    Abramovicz-Finkelsztain, Renata; Barsottini, Claudia G N; Marin, Heimar Fatima

    2015-01-01

    The use of Electronic Dental Records (EDRs) and management software has become more frequent, following the increase in prevelance of new technologies and computers in dental offices. The purpose of this study is to identify and evaluate the use of EDRs by the dental community in the São Paulo city area. A quantitative case study was performed using a survey on the phone. A total of 54 offices were contacted and only one declinedparticipation in this study. Only one office did not have a computer. EDRs were used in 28 offices and only four were paperless. The lack of studies in this area suggests the need for more usability and implementation studies on EDRs so that we can improve EDR adoption by the dental community.

  3. Electronic states in systems of reduced dimensionality

    International Nuclear Information System (INIS)

    This report briefly discusses the following research: magnetically modulated systems, inelastic magnetotunneling, ballistic transport review, screening in reduced dimensions, raman and electron energy loss spectroscopy; and ballistic quantum interference effects. (LSP)

  4. 高位池塘循环水养鱼系统生产性试验总结%Summary of productive experiment on recycling intensive pond aquaculture system with zero emission

    Institute of Scientific and Technical Information of China (English)

    郭益顿; 顾向军; 徐国昌; 王小冬

    2011-01-01

    In order to achieving the aim of zero emission, low pollution, high quality and no remaining medicine in aquaculture, an intensive aquaculture system of zero emission was developed through our own production of aquaculture machinery and operation experiences. The system included mainly the aeration machine, water treatment machine and dirt-gathering facility. And an integrated productive experiment was carried out during 16 July to 4 November, 2010. The initial input amount of snoek fry was 14 000, with the size of about 60-80 fry/500 g. During the experiment with the intensive pond of 870 m2, the dissolved oxygen was above 3.5 mg/L, and the ammonium nitrogen was lower than 0.3 mg/L, and the nitrite nitrogen was lower than 0.4 mg/L, showing the water quality was relatively good. The total finished product of snoek from the pond was 5 035 kg, and the pure profit was 40 700 yuan RMB. The experiment achieved the expected aim of high investment, high yield, zero emission and no remaining medicine, which can provide reference for construction of recycling intensive pond aquaculture of zero emission.%为了达到水产养殖零排放,低污染,高品质,无残药等目的,研制了一套高位池塘循环水养鱼系统.该系统主要包括增氧设备、循环水水处理系统及集污设备等.完整的生产性养殖试验时间为2010年7月16日至11月4日.试验初始投入的梭鱼(Chelon haematocheilus)苗共14000尾,规格为60~80尾/500 g.试验期间,在870 m的高位池中,溶氧维持在3.5 mg/L以上,氨氮低于0.3 mg/,L,亚硝酸盐低于0.4 mg/L,池塘水体的水质状况较好.该高位池共产出成品梭鱼5 035 kg,实现纯利润40 700元.试验达到了高投入、高产出、零排放、无药残等预期目标,可为高位池塘循环水养殖系统建设提供参考.

  5. Facilitating electron transfer in bioelectrocatalytic systems

    OpenAIRE

    Sekretaryova, Alina

    2016-01-01

    Bioelectrocatalytic systems are based on biological entities, such as enzymes, whole cells, parts of cells or tissues, which catalyse electrochemical processes that involve the interaction between chemical change and electrical energy. In all cases, biocatalysis is implemented by enzymes, isolated or residing inside cells or part of cells. Electron transfer (ET) phenomena, within the protein molecules and between biological redox systems and electronics, enable the development of various bioe...

  6. Design of monitoring system of aquaculture based on Android and GPRS%基于 Android和 GPRS的水产养殖监控系统设计

    Institute of Scientific and Technical Information of China (English)

    崇庆峰; 刘星桥; 宦娟; 徐晨虎; 李慧

    2013-01-01

    province, all the indexes could meet the requirements with the temperature measurement accuracy of ±0.5℃, pH measurement accuracyof ±0.3, water level control precision being controlled within ± 3 cm, dissolved oxygen control precision being controlled within ±0.3 mg/L, therefore this system is very suitable and applicable for aquaculture industry .

  7. Data base systems in electronic design engineering

    Science.gov (United States)

    Williams, D.

    1980-01-01

    The concepts of an integrated design data base system (DBMS) as it might apply to an electronic design company are discussed. Data elements of documentation, project specifications, project tracking, firmware, software, electronic and mechanical design can be integrated and managed through a single DBMS. Combining the attributes of a DBMS data handler with specialized systems and functional data can provide users with maximum flexibility, reduced redundancy, and increased overall systems performance. Although some system overhead is lost due to redundancy in transitory data, it is believed the combination of the two data types is advisable rather than trying to do all data handling through a single DBMS.

  8. An Internet Based Anonymous Electronic Cash System

    Directory of Open Access Journals (Sweden)

    Israt Jahan

    2015-04-01

    Full Text Available There is an increase activity in research to improve the current electronic payment system which is parallel with the progress of internet. Electronic cash system is a cryptographic payment system which offers anonymity during withdrawal and purchase. Electronic cash displays serial numbers which can be recorded to allow further tracing. Contrary to their physical counterparts, e-cash have an inherent limitation; they are easy to copy and reuse (double-spending. An observer is a tamper-resistant device, issued by the Internet bank, which is incorporated with the Internet user’s computer that prevents double-spending physically, i.e., the user has no access to her e-cash and therefore he cannot copy them. In this paper, we shall present an anonymous electronic cash scheme on the internet which incorporates tamper-resistant device with user-module.

  9. Security in Electronic Payment Systems

    Directory of Open Access Journals (Sweden)

    Roxana Turcu

    2014-12-01

    Full Text Available The payment security becomes fundamental in our days. Based on this statement I have decided to deepen this subject and to study the online payment systems and the connection between them. I have observed that this area becomes the hackers’ attraction and I have realized how important the security of the ecommerce is. Also I have done a research of the possible attacks and I have searched for the countermeasures of this attacks. The result of my research is my payment gateway solution presented in the following lines.

  10. Aquaculture Engineering: Status and Roles in the Growth of Aquaculture Industry in Nigeria

    Directory of Open Access Journals (Sweden)

    Mrs. Nene A. Jamabo

    2010-11-01

    Full Text Available This study reviews the role of aquaculture engineering in Nigeria’s aquaculture sub-sector. The focus was on solving site selection problems due to environmental, Climatic and hydrological factors, equipment selection and fabrication, and site specific engineering problems. The poor growth of the aquaculture industry in Nigeria in the past is attributed to the poor status of aquaculture engineering. Also emphasis was placed on the shortage of qualified manpower, aquaculture engineers, in Nigeria, and suggestions were made for the short, medium and long term solutions. It is hoped that this review article will elicit a positive shift in policy towards aquaculture engineering in Nigeria and beyond.

  11. Symmetry of many-electron systems

    CERN Document Server

    Kaplan, I G

    2013-01-01

    Symmetry of Many-Electron Systems discusses the group-theoretical methods applied to physical and chemical problems. Group theory allows an individual to analyze qualitatively the elements of a certain system in scope. The text evaluates the characteristics of the Schrodinger equations. It is proved that some groups of continuous transformation from the Lie groups are useful in identifying conditions and in developing wavefunctions. A section of the book is devoted to the utilization of group-theoretical methods in quantal calculations on many-electron systems. The focus is on the use of group

  12. Power Electronics in Wind Turbine Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Chen, Zhe; Teodorescu, Remus;

    2006-01-01

    the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power systems, power production and end-user application. This paper discuss the most emerging renewable energy source, wind energy, which by means of power...... electronics is changing from being a minor energy source to be acting as an important power source in the energy system. By that wind power is also getting an added value in the power system operation....

  13. Sensor Arrays and Electronic Tongue Systems

    Directory of Open Access Journals (Sweden)

    Manel del Valle

    2012-01-01

    Full Text Available This paper describes recent work performed with electronic tongue systems utilizing electrochemical sensors. The electronic tongues concept is a new trend in sensors that uses arrays of sensors together with chemometric tools to unravel the complex information generated. Initial contributions and also the most used variant employ conventional ion selective electrodes, in which it is named potentiometric electronic tongue. The second important variant is the one that employs voltammetry for its operation. As chemometric processing tool, the use of artificial neural networks as the preferred data processing variant will be described. The use of the sensor arrays inserted in flow injection or sequential injection systems will exemplify attempts made to automate the operation of electronic tongues. Significant use of biosensors, mainly enzyme-based, to form what is already named bioelectronic tongue will be also presented. Application examples will be illustrated with selected study cases from the Sensors and Biosensors Group at the Autonomous University of Barcelona.

  14. Identification of specific demands on Feed in Dutch Organic Aquaculture

    NARCIS (Netherlands)

    Poelman, M.

    2009-01-01

    The evaluation of specific demands for organic feed focussed on feed demands for four fish species which can be cultured in Recirculation Aquaculture Systems (RAS), tilapia, African Catfish, shrimp and turbot. The evaluation of the various feed formulations indicates that there are several ingredien

  15. VHDL Model of Electronic-Lock System

    Directory of Open Access Journals (Sweden)

    J. Noga

    2000-04-01

    Full Text Available The paper describes the design of an electronic-lock system which wascompleted as part of the Basic VHDL course in the Department of Controland Measurement Faculty of Electrical Engineering and Informatics,Technical University of Ostrava, Czech Republic in co-operation withthe Department if Electronic Engineering, University of Hull, GreatBritain in the frame of TEMPUS project no. S_JEP/09468-95.

  16. VHDL Model of Electronic-Lock System

    OpenAIRE

    J. Noga; E. Bartsch; I. M. Bell; Miklik, D.; Bannister, B. R.; K. Vlcek

    2000-01-01

    The paper describes the design of an electronic-lock system which was completed as part of the Basic VHDL course in the Department of Control and Measurement Faculty of Electrical Engineering and Informatics, Technical University of Ostrava, Czech Republic in co-operation with the Department if Electronic Engineering, University of Hull, Great Britain in the frame of TEMPUS project no. S_JEP/09468-95.

  17. 76 FR 9210 - Draft DOC National Aquaculture Policy

    Science.gov (United States)

    2011-02-16

    ... DOC National Aquaculture Policy AGENCY: Commerce. ACTION: Notice of availability of draft aquaculture... draft national aquaculture policy that supports sustainable aquaculture in the United States. The intent of the policy is to guide DOC's actions and decisions on aquaculture and to provide a...

  18. Oxygen absorption efficiency of gas/liquid mixing device in closed recirculating aquaculture systems%闭合循环水产养殖系统中气/液混合装置的增氧效果

    Institute of Scientific and Technical Information of China (English)

    谭洪新; 刘文畅; 孙大川; 罗国芝; 马念念

    2014-01-01

    为了研究纯氧气/液混合装置在循环水养殖系统中的实际使用效果,对闭合循环水产养殖系统中气/液混合装置的氧气吸收效率(absorption efficiency,AE)及运行效果进行了研究。结果表明,气/液混合比(gas to liquid ratio,G/L)变化在0.333%~3.333%(O2流量0.57~5.70 g/min)之间时,气/液混合装置的平均氧气吸收效率变化在94.001%~36.049%之间。当G/L=0.667%(O2流量1.141 g/min),在30.5℃、26.3℃、22.9℃和19.2℃水温条件下,气/液混合装置的氧气吸收效率别为87.833%、90.451%、93.606%和94.001%;其中,试验水温为19.2℃时, AE达到最大(94.001%),混合器出水溶解氧浓度达13.36 mg/L。当G/L大于或小于0.667%时,AE均随G/L的变化而降低;各温度组AE值的方差分析表明,温度对AE值有显著影响。%Control of dissolved gases, especially oxygen and carbon dioxide, is an essential component of closed recirculating aquaculture systems. The use of oxygenation in closed recirculating aquaculture systems increases the mass of fish that can be supported in a given water flow by removing oxygen as a limiting factor to a system’s carrying capacity. In general, oxygenation technique in aquaculture is relatively mature with well established operational principles, techniques, and equipment. Since the 1970s, pure oxygen gas has been used as an economical means of providing supersaturated dissolved oxygen and thereby intensifying fish production in recirculating systems. Use of pure oxygen can lower fish production costs by supporting high fish and feed loading rates and reducing water flow requirements, which in turn reduces the size and cost of pumping, culture tanks, and water reuse equipment. Transferring pure oxygen rather than air into water can increase the mol fraction of gaseous oxygen and solubility of dissolved oxygen in water. The maximal dissolved oxygen concentration can be influenced by the

  19. Power electronics system modeling and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jih-Sheng

    1994-12-31

    This paper introduces control system design based softwares, SIMNON and MATLAB/SIMULINK, for power electronics system simulation. A complete power electronics system typically consists of a rectifier bridge along with its smoothing capacitor, an inverter, and a motor. The system components, featuring discrete or continuous, linear or nonlinear, are modeled in mathematical equations. Inverter control methods,such as pulse-width-modulation and hysteresis current control, are expressed in either computer algorithms or digital circuits. After describing component models and control methods, computer programs are then developed for complete systems simulation. Simulation results are mainly used for studying system performances, such as input and output current harmonics, torque ripples, and speed responses. Key computer programs and simulation results are demonstrated for educational purposes.

  20. A Flexible Electronic Commerce Recommendation System

    Science.gov (United States)

    Gong, Songjie

    Recommendation systems have become very popular in E-commerce websites. Many of the largest commerce websites are already using recommender technologies to help their customers find products to purchase. An electronic commerce recommendation system learns from a customer and recommends products that the customer will find most valuable from among the available products. But most recommendation methods are hard-wired into the system and they support only fixed recommendations. This paper presented a framework of flexible electronic commerce recommendation system. The framework is composed by user model interface, recommendation engine, recommendation strategy model, recommendation technology group, user interest model and database interface. In the recommender strategy model, the method can be collaborative filtering, content-based filtering, mining associate rules method, knowledge-based filtering method or the mixed method. The system mapped the implementation and demand through strategy model, and the whole system would be design as standard parts to adapt to the change of the recommendation strategy.

  1. Status of Irish Aquaculture 2005

    OpenAIRE

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2006-01-01

    This is the third annual report on the status of Irish aquaculture (see Parsons et al., 2003, Parsons et al., 2004). As with the previous reports it has been produced in collaboration with the three main State agencies that provide support services in the areas of research and development to the industry – Bord Iascaigh Mhara (BIM), the Marine Institute (MI) and Taighde Mara Teo (TMT). The objectives of this report are: (1) To provide a useful, objective and comprehensive source of informatio...

  2. Aquaculture: global status and trends

    OpenAIRE

    Bostock, John; McAndrew, Brendan; Richards, Randolph; Jauncey, Kim; Telfer, Trevor; Lorenzen, Kai; Little, David; Ross, Lindsay; Handisyde, Neil; Gatward, Iain; Corner, Richard

    2010-01-01

    Aquaculture contributed 43 per cent of aquatic animal food for human consumption in 2007 (e.g. fish, crustaceans and molluscs, but excluding mammals, reptiles and aquatic plants) and is expected to grow further to meet the future demand. It is very diverse and, contrary to many perceptions, dominated by shellfish and herbivorous and omnivorous pond fish either entirely or partly utilizing natural productivity. The rapid growth in the production of carnivorous species such as salmon, shrimp an...

  3. Training in African aquaculture development

    OpenAIRE

    Brummett, R. E.

    1994-01-01

    The article focuses on the types of training needed in African aquaculture development. The author suggested that rather than needing less training, extension agents and others who operate in the idiosyncratic world of the poor African farmer, need a far deeper understanding of fish culture (particularly the basics of pond dynamics and ecology) than do those who can take advantage of industrialized-country infrastructure.

  4. Science, the Environment and Aquaculture

    Institute of Scientific and Technical Information of China (English)

    Liu Jian

    2002-01-01

    This paper first analyzes the problems of natural resources, the environment and agriculture in China. Secondly, it discusses the challenge of sustaining a healthy aquaculture. Thirdly, the role of science and technology in environmental management is described in detail, explaining the interaction between research and implication for govemment policymaking and local authority implementation. Finally, the institutes of the Chinese Academy of Sciences (CAS) concerned with studies of aquatic ecosystem management are introduced as examples.

  5. 工厂化循环水养殖系统中 pH 维持系统研究%Study on pH maintains system in the factory recirculating aquaculture

    Institute of Scientific and Technical Information of China (English)

    张业韡; 张海耿; 吴凡

    2013-01-01

    为精确调节循环水养殖系统中水体的pH,使鱼类生长在最适宜环境中,建立了一种新的pH维持系统。系统采用新型控制算法,通过向养殖水体持续加碱,将水体中的pH维持在一个稳定的数值。试验设定pH的目标值为74.,采用组态软件运行将PID、TCP、预判等多种计算相结合的算法来改变计量泵的输出流量,通过计量泵向调节池中持续注入碳酸氢钠( NaHCO3)溶液,以平衡水体中碱的消耗,最终将系统水体的pH长时间稳定在7.4±0.01的范围内。本pH维持系统能实现对循环水养殖系统中水体pH的精确调控,对维持水质的稳定及促进鱼类的健康生长具有重要意义。%In order to accurately regulate the pH of recirculating aquaculture systems , and build a suitable fish growth environment , we set up a new pH maintain system .The system adopts a new control algorithm , through using the method of continuous adding alkali into aquaculture ponds to maintain the pH of water at a stable value.This test set target the values of pH at 7.4, and combined PID, TCP, anticipation and various calculation algorithms to change metering pump output flow through using configuration software .Through injecting NaHCO 3 solution by metering pump continually , it could balance the consumption of alkali in water and make the pH stability for a long time in the range of 7.4 ±0.01.The pH maintain system could realize the pH of precise control in the recirculating aquaculture system , and keep the stability of water quality .It had important significance of promoting the healthy growth of fish .

  6. Criteria for candidate species for aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Webber, H.H.; Riordan, P.F.

    1976-01-01

    The nature of the animal taxa that are the most probable candidates for an intensive, commercial aquatic animal husbandry industry is considered. A characterization is presented of those biological criteria that lend the species the necessary physiological and genetic malleability to be adapted and molded into a domesticated race. The animal cultivated must be amenable to intensive management in high-density confinements such as those now being engineered for high-yield aquaculture. Attributes considered are discussed in the context of the various aquacultural ecosystems in which the specific biotype is expected to achieve satisfactory growth and survival. Correlative with bionomic criteria, economic requirements are posed and evaluated in an effort to define a socially and financially profitable agribusiness system. Investment requirements and operating costs are considered in terms of expected returns. However, since production alone is insufficient to sustain an enterprise - i.e., the product must be sold - production costs must be judged against market values. Therefore, ultimate use or consumer acceptance criteria are incorporated into the list of essential requirements for a candidate species for aquafarming.

  7. Power Electronics for Renewable Energy Systems

    DEFF Research Database (Denmark)

    Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

    2012-01-01

    The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds...... of renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...

  8. Electronic system of TBR tokamak device

    International Nuclear Information System (INIS)

    The electronics developed as a part of the TBR project, which involves the construction of a small tokamak at the Physics Institute of the University of Sao Paulo, is described. On the basis of tokamak parameter values, the electronics for the toroidal field, ohmic/heating and vertical field systems is presented, including capacitors bank, switches, triggering circuits and power supplies. A controlled power oscilator used in discharge cleaning and pre-ionization is also described. The performance of the system as a function of the desired plasma parameters is discussed. (Author)

  9. Prognostics for Electronics Components of Avionics Systems

    Science.gov (United States)

    Celaya, Jose R.; Saha, Bhaskar; Wysocki, Philip F.; Goebel, Kai F.

    2009-01-01

    Electronics components have and increasingly critical role in avionics systems and for the development of future aircraft systems. Prognostics of such components is becoming a very important research filed as a result of the need to provide aircraft systems with system level health management. This paper reports on a prognostics application for electronics components of avionics systems, in particular, its application to the Isolated Gate Bipolar Transistor (IGBT). The remaining useful life prediction for the IGBT is based on the particle filter framework, leveraging data from an accelerated aging tests on IGBTs. The accelerated aging test provided thermal-electrical overstress by applying thermal cycling to the device. In-situ state monitoring, including measurements of the steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  10. Electronic warfare receivers and receiving systems

    CERN Document Server

    Poisel, Richard A

    2014-01-01

    Receivers systems are considered the core of electronic warfare (EW) intercept systems. Without them, the fundamental purpose of such systems is null and void. This book considers the major elements that make up receiver systems and the receivers that go in them.This resource provides system design engineers with techniques for design and development of EW receivers for modern modulations (spread spectrum) in addition to receivers for older, common modulation formats. Each major module in these receivers is considered in detail. Design information is included as well as performance tradeoffs o

  11. Printed Carbon Nanotube Electronics and Sensor Systems.

    Science.gov (United States)

    Chen, Kevin; Gao, Wei; Emaminejad, Sam; Kiriya, Daisuke; Ota, Hiroki; Nyein, Hnin Yin Yin; Takei, Kuniharu; Javey, Ali

    2016-06-01

    Printing technologies offer large-area, high-throughput production capabilities for electronics and sensors on mechanically flexible substrates that can conformally cover different surfaces. These capabilities enable a wide range of new applications such as low-cost disposable electronics for health monitoring and wearables, extremely large format electronic displays, interactive wallpapers, and sensing arrays. Solution-processed carbon nanotubes have been shown to be a promising candidate for such printing processes, offering stable devices with high performance. Here, recent progress made in printed carbon nanotube electronics is discussed in terms of materials, processing, devices, and applications. Research challenges and opportunities moving forward from processing and system-level integration points of view are also discussed for enabling practical applications.

  12. Stringency of environmental regulation and aquaculture growth

    DEFF Research Database (Denmark)

    Gedefaw Abate, Tenaw; Nielsen, Rasmus; Tveterås, Ragnar

    2016-01-01

    remarkable growth in aquaculture while others have stagnated or even declined have not been determined. In this article, we investigate whether environmental regulations have an impact on aquaculture growth. Using a cross-country regression analysis, we show that stringent environmental regulations...... are negatively related to aquaculture growth, whereas GDP growth has a positive effect. Countries often face a difficult balancing act between growth and environmental considerations when devising regulations. Our empirical results suggest that stricter environmental regulations in developed countries have...

  13. 工厂化循环水养殖中臭氧/紫外线反应系统的水处理性能%Water treatment performance of O3/UV reaction system in recirculating aquaculture systems

    Institute of Scientific and Technical Information of China (English)

    管崇武; 杨菁; 单建军; 张海耿; 刘晃; 王欣

    2014-01-01

    为增强臭氧在水产应用的安全性,满足工厂化循环水养殖对有机物去除和水体消毒的需要,该文开发O3/UV反应系统。通过试验方法研究该系统臭氧投加溶解区适宜的臭氧投加流量和处理量的关系、紫外辐射剂量配比等工艺参数,及对水质净化效果和水体消毒灭菌效果的影响等。试验结果表明:1)在满足所需水中溶解臭氧浓度的条件下,采用较低臭氧进气流量和较高进水流量有利于提高系统的臭氧溶解率和利用率。该系统在水流量为5 m3/h,臭氧投加量为(8.78±0.60)g/h时可得到水中臭氧溶解质量浓度为1.53 mg/L的臭氧水,臭氧溶解率为82.7%,臭氧利用率为97.7%。2)增加紫外灯的功率和数量均可提高对臭氧的去除率,但增加紫外灯的数量对其性能提升效果更明显。该系统在紫外剂量为1996 MJ/cm2,对残留臭氧的去除率为83.82%。3)该系统对紫外消光度、总有机碳、水色等指标的去除率相比单独使用臭氧分别提升109.95%、89.77%和51.44%,杀菌率可达97%以上,实现工厂化循环水养殖低臭氧残留条件下的有机物有效去除和消毒杀菌。%In order to improve the water treatment performance of ozone in recirculating aquaculture systems, and enhance its application safety in the field of aquaculture, the O3/UV integration reaction system were designed. The reaction system was mainly composed of ozone addition dissolved area, ultraviolet catalytic reaction area, stay reaction area. The system was 1 250 mm of high, 750 mm in diameter, and the ultraviolet catalytic reaction was 400 mm in diameter. The working principle of system was that using static mixer way to add ozone, which could dissolve wastewater high efficiency and low energy consumption in ozone addition dissolved area. The wastewater with not completely dissolved ozone bottom up entered to ultraviolet catalytic reaction area, which could generate two

  14. Design for Reliability of Power Electronic Systems

    DEFF Research Database (Denmark)

    Wang, Huai; Ma, Ke; Blaabjerg, Frede

    2012-01-01

    Advances in power electronics enable efficient and flexible processing of electric power in the application of renewable energy sources, electric vehicles, adjustable-speed drives, etc. More and more efforts are devoted to better power electronic systems in terms of reliability to ensure high...... availability, long lifetime, sufficient robustness, low maintenance cost and low cost of energy. However, the reliability predictions are still dominantly according to outdated models and terms, such as MIL-HDBK-217F handbook models, Mean-Time-To-Failure (MTTF), and Mean-Time-Between-Failures (MTBF...... on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical components IGBTs. Different aspects of improving the reliability of the power converter are mapped. Finally, the challenges and opportunities to achieve more reliable power electronic systems are addressed....

  15. Current status of the research about the carbon source of the heterotrophic denitrification of recirculating aquaculture system%循环水养殖用水中反硝化碳源研究现状

    Institute of Scientific and Technical Information of China (English)

    罗国芝; 鲁璐; 杜军; 刘倩; 董明来

    2011-01-01

    通过硝化作用和反硝化作用可以有效控制循环水养殖系统水中的氧氮、亚硝酸盐和硝酸盐.进行水产养殖用水硝化作用的生物过滤器的研究已经系统而深入,而关于养殖用水反硝化作用的脱氮反应器的研究则并未引起相应的关注.水产养殖用水进行异养反硝化必需添加碳源.在已有的研究中,经常使用的甲醇等有机液体碳源存在添加量不易控制、出水有残留等弊端;可生物降解聚合物被证明是比较理想的水产养殖用水异养反硝化碳源的选择之一;近年来对以养殖活动中产生的残饵和粪便作为异养反硝化内供碳源的研究也引起了广泛的关注.总结了近年来循环水养殖系统异养反硝化不同种类碳源的效率、在实际生产中的可操作性的相关研究进展.%Aerobic biological filtration systems employing nitrifying bacteria to remediate excess ammonia and nitrite concentrations are common components of recirculating aquaculture systems (RAS).Nitrite is the end result of the nitrification and is removed either by a denitrification process that ideally converts nitrate-N to nitrogen gas or by water exchange.The disadvantage of denitrification treatment with liquid carbon source is the need of a close, rather sophisticated and costly process control, the risk of overdosing and a deepened knowledge about the operation of this biological system.The biodegradable polymers as substrate and biofilm carriers is better choice for the denitrification progress of the aquaculture water.The organic solid-wastes taken from the solids-filter of a RAS as carbon source which termed single-sludge denitrification is induced much interest today.This paper reviewed the organic carbon source used in the denitrification of the aquaculture water mainly about the production scale farm.

  16. Electronic Chart Display and Information System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper introduces the most advanced form of electronic chart display and information systems (ECDIS) which complies with the Performance Standards for ECDIS established by the International Maritime Organization (IMO) and the International Hydrographic Organization (IHO).It also describes the key features and the important functions of ECDIS.Then the future development of ECDIS in marine is discussed.

  17. Monitoring bacterial diversity of the marine sponge Ircinia strobilina upon transfer into aquaculture.

    Science.gov (United States)

    Mohamed, Naglaa M; Rao, Venkateswara; Hamann, Mark T; Kelly, Michelle; Hill, Russell T

    2008-07-01

    Marine sponges in the genus Ircinia are known to be good sources of secondary metabolites with biological activities. A major obstacle in the development of sponge-derived metabolites is the difficulty in ensuring an economic, sustainable supply of the metabolites. A promising strategy is the ex situ culture of sponges in closed or semiclosed aquaculture systems. In this study, the marine sponge Ircinia strobilina (order Dictyoceratida: family Irciniidae) was collected from the wild and maintained for a year in a recirculating aquaculture system. Microbiological and molecular community analyses were performed on freshly collected sponges and sponges maintained in aquaculture for 3 months and 9 months. Chemical analyses were performed on wild collected sponges and individuals maintained in aquaculture for 3 months and 1 year. Denaturing gradient gel electrophoresis was used to assess the complexity of and to monitor changes in the microbial communities associated with I. strobilina. Culture-based and molecular techniques showed an increase in the Bacteroidetes and Alpha- and Gammaproteobacteria components of the bacterial community in aquaculture. Populations affiliated with Beta- and Deltaproteobacteria, Clostridia, and Planctomycetes emerged in sponges maintained in aquaculture. The diversity of bacterial communities increased upon transfer into aquaculture. PMID:18469126

  18. Electronic system for optical shutter control

    Science.gov (United States)

    Viljoen, H. C.; Gaylord, T. K.

    1976-01-01

    The paper describes a precise and versatile electronic system for shutter control in light beam experiments. Digital and analog circuitry is used to provide automatic timing, exposure control, manual operation, and remote programmability. A block diagram of the system is presented and the individual circuits - the timer control circuit, the clock control circuit, the comparator circuit, the exposure (integrator) circuit, and the shutter drive circuit are discussed in detail and diagrams are provided.

  19. Soft errors in modern electronic systems

    CERN Document Server

    Nicolaidis, Michael

    2010-01-01

    This book provides a comprehensive presentation of the most advanced research results and technological developments enabling understanding, qualifying and mitigating the soft errors effect in advanced electronics, including the fundamental physical mechanisms of radiation induced soft errors, the various steps that lead to a system failure, the modelling and simulation of soft error at various levels (including physical, electrical, netlist, event driven, RTL, and system level modelling and simulation), hardware fault injection, accelerated radiation testing and natural environment testing, s

  20. 600-GHz Electronically Tunable Vector Measurement System

    Science.gov (United States)

    Dengler, Robert; Maiwald, Frank; Siegel, Peter

    2007-01-01

    A compact, high-dynamic-range, electronically tunable vector measurement system that operates in the frequency range from approximately 560 to approximately 635 GHz has been developed as a prototype of vector measurement systems that would be suitable for use in nearly-real-time active submillimeter-wave imaging. As used here, 'vector measurement system" signifies an instrumentation system that applies a radio-frequency (RF) excitation to an object of interest and measures the resulting amplitude and phase response, relative to either the applied excitatory signal or another reference signal related in a known way to applied excitatory signal.

  1. Electron gun system for NSC KIPT linac

    CERN Document Server

    Zhou, Zusheng; Chi, Yunlong

    2013-01-01

    In NSC KIPT linac, a neutron source based on a subcritical assembly driven by a 100MeV/100kW electron linear accelerator is under design and development. The linear accelerator needs a new high current electron gun. In this paper, the physical design, mechanical fabrication and beam test of this new electron gun are described. The emission current is designed to be higher than 2A for the pulse width of 3us with repetition rate of 50 Hz. The gun will operate with a DC high voltage power supply which can provide a high voltage up to 150 kV. . Computer simulations and optimizations have been carried out in the design stage, including the gun geometry and beam transport line. The test results of high voltage conditioning and beam test are presented. The operation status of the electron gun system is also included. The basic test results show that the design, manufacture and operation of the new electron system are basically successful.

  2. Cooperative phenomena in strongly correlated electron systems

    Science.gov (United States)

    Farkašovský, Pavol

    2010-10-01

    In this review we present results of our theoretical study of cooperative phenomena in strongly correlated electron systems obtained within various generalizations of the Falicov-Kimball model. The primary goal of this study was to identify crucial interactions that lead to the stabilization of the specific cooperative phenomenon, and then try to elaborate its comprehensive microscopic description. The main attention is devoted to a discussion of valence and metal-insulator transitions, formation of charge and spin ordering, electronic ferroelectricity, itinerant ferromagmetism and mechanisms leading to their stabilization. Among the major mechanisms we examine the effect of local and nonlocal Coulomb interaction between localized and itinerant electrons, local and nonlocal hybridization, long-range and correlated hopping of itinerant electrons and spin-dependent interaction between localized and itinerant electrons, both for zero and nonzero temperatures, as well as for doped and undoped systems. Finally, the relevance of resultant solutions for a description of rare-earth and transition-metal compounds is discussed.

  3. Cooperative phenomena in strongly correlated electron systems

    International Nuclear Information System (INIS)

    In this review we present results of our theoretical study of cooperative phenomena in strongly correlated electron systems obtained within various generalizations of the Falicov-Kimball model. The primary goal of this study was to identify crucial interactions that lead to the stabilization of the specific cooperative phenomenon, and then try to elaborate its comprehensive microscopic description. The main attention is devoted to a discussion of valence and metal-insulator transitions, formation of charge and spin ordering, electronic ferroelectricity, itinerant ferromagmetism and mechanisms leading to their stabilization. Among the major mechanisms we examine the effect of local and nonlocal Coulomb interaction between localized and itinerant electrons, local and nonlocal hybridization, long-range and correlated hopping of itinerant electrons and spin-dependent interaction between localized and itinerant electrons, both for zero and nonzero temperatures, as well as for doped and undoped systems. Finally, the relevance of resultant solutions for a description of rare-earth and transition-metal compounds is discussed (Author)

  4. Directly measured denitrification reveals oyster aquaculture and restored oyster reefs remove nitrogen at comparable high rates

    Science.gov (United States)

    Coastal systems are increasingly impacted by over-enrichment of nutrients, which has cascading effects for ecosystem functioning. Oyster restoration and aquaculture are both hypothesized to mitigate excessive nitrogen (N) loads via benthic denitrification (DNF). However, this has...

  5. The role of oyster restoration and aquaculture in nitrogen removal within a Rhode Island estuary

    Science.gov (United States)

    Coastal systems are increasingly impacted by over-enrichment of nutrients, which has cascading effects for ecosystem functioning. Oyster aquaculture and restoration are hypothesized to mitigate excessive nitrogen (N) loads via assimilation, burial, or benthic denitrification. Stu...

  6. Evaluation of geotextile filtration applying coagulant and flocculant amendments for aquaculture biosolids dewatering and phosphorus removal

    Science.gov (United States)

    Wastes contained in the microscreen backwash discharged from intensive recirculating aquaculture systems were removed and dewatered in simple geotextile bag filters. Three chemical coagulation aids, (aluminum sulfate (alum), ferric chloride, and calcium hydroxide (hydrated lime)), were tested in com...

  7. Zebrafish as Animal Model for Aquaculture Nutrition Research

    Directory of Open Access Journals (Sweden)

    Pilar Elizabeth Ulloa

    2014-09-01

    Full Text Available The aquaculture industry continues to promote the diversification of ingredients used in aquafeed in order to achieve a more sustainable aquaculture production system. The evaluation of large numbers of diets in aquaculture species is costly and requires time-consuming trials in some species. In contrast, zebrafish (Danio rerio can solve these drawbacks as an experimental model, and represents an ideal organism to carry out preliminary evaluation of diets. In addition, zebrafish has a sequenced genome allowing the efficient utilization of new technologies, such as RNA-sequencing and genotyping platforms to study the molecular mechanisms that underlie the organism’s response to nutrients. Also, biotechnological tools like transgenic lines with fluorescently labeled neutrophils that allow the evaluation of the immune response in vivo, are readily available in this species. Thus, zebrafish provides an attractive platform for testing many ingredients to select those with the highest potential of success in aquaculture. In this perspective aspects related to diet evaluation in which zebrafish can make important contributions to nutritional genomics and nutritional immunity are discussed.

  8. Ocean modelling for aquaculture and fisheries in Irish waters

    Science.gov (United States)

    Dabrowski, T.; Lyons, K.; Cusack, C.; Casal, G.; Berry, A.; Nolan, G. D.

    2016-01-01

    The Marine Institute, Ireland, runs a suite of operational regional and coastal ocean models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. The authors give an overview of a shellfish model developed in-house and that was designed to predict the growth, the physiological interactions with the ecosystem, and the level of coliform contamination of the blue mussel. As such, this model is applicable in studies on the carrying capacity of embayments, assessment of the impacts of pollution on aquaculture grounds, and the determination of shellfish water classes. Further services include the assimilation of the model-predicted shelf water movement into a new harmful algal bloom alert system used to inform end users of potential toxic shellfish events and high biomass blooms that include fish-killing species. Models are also used to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish, and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the resources of marine fisheries. This paper demonstrates that ocean models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.

  9. Ocean modelling for aquaculture and fisheries in Irish waters

    Directory of Open Access Journals (Sweden)

    T. Dabrowski

    2015-06-01

    Full Text Available The Marine Institute, Ireland, runs a suite of operational regional and coastal ocean models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. A shellfish model that includes growth and physiological interactions of mussels with the ecosystem and is fully embedded in the 3-D numerical modelling framework has been developed at the Marine Institute. This shellfish model has a microbial module designed to predict levels of coliform contamination in mussels. This model can also be used to estimate the carrying capacity of embayments, assess impacts of pollution on aquaculture grounds and help to classify shellfish waters. The physical coastal model of southwest Ireland provides a three day forecast of shelf water movement in the region. This is assimilated into a new harmful algal bloom alert system used to inform end-users of potential toxic shellfish events and high biomass blooms that include fish killing species. Further services include the use of models to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the marine fisheries resources. This paper demonstrates that ocean models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.

  10. Copper Ion Accumulation in Litopenaeus Vannamei and the Effect on Metallothionein in Different Aquaculture Systems%铜离子在养殖对虾组织中的积累及其对金属硫蛋白含量的影响

    Institute of Scientific and Technical Information of China (English)

    李湘萍; 程波; 程江峰; 刘鹰

    2011-01-01

    为考察铜在循环水与静水养殖系统的凡纳滨对虾组织中的积累,本实验在两种养殖系统中分别添加硫酸铜,并使其浓度保持一致,经过92 d的培养,对铜在虾组织中的积累量进行了测定.结果表明,在两种系统中养殖的对虾,其组织中铜浓度依次为:肝胰t>鳃丝>甲壳>肌肉,肝胰腺中金属硫蛋白(MT)与肝胰腺中铜的积累有相似变化趋势.循环水系统与静水系统中虾肝胰腺和甲壳中铜的积累量有显著差异,而两种系统中虾鳃丝中铜的积累量差异不明显.%In order to study the accumulation of copper ion in shrimp of different aqua-culture systems, we added a certain concentration of sulfate copper in aquaculture systems and kept in the same level during the experiment. After 92 d, the accumulation of copper ion in different tissues and systems were analyzed. The copper accumulation in different tissues both in recirculating aquaculture system (RAS) and static aquaculture system (SAS) had the same accumulation currence: hepatopancreas > lamella > cara-pace> muscle. The concentration of metallothionein(MT) in hepatopancreas had the same change with the copper accumulation. The accumulation of copper in hepatopancreas and carapace in different aquaculture systems had significant difference, while copper ion in lamella changed insignificantly.

  11. Effects of seawater ozonation on biofilm development in aquaculture tanks.

    Science.gov (United States)

    Wietz, Matthias; Hall, Michael R; Høj, Lone

    2009-07-01

    Microbial biofilms developing in aquaculture tanks represent a reservoir for opportunistic bacterial pathogens, and procedures to control formation and bacterial composition of biofilms are important for the development of commercially viable aquaculture industries. This study investigated the effects of seawater ozonation on biofilm development on microscope glass slides placed in small-scale aquaculture tanks containing the live feed organism Artemia. Fluorescence in situ hybridization (FISH) demonstrated that ozonation accelerated the biofilm formation cycle, while it delayed the establishment of filamentous bacteria. Gammaproteobacteria and Alphaproteobacteria were the most abundant bacterial groups in the biofilm for both water types, but ozonation influenced their dynamics. With ozonation, the bacterial community structure was relatively stable and dominated by Gammaproteobacteria throughout the experiment (21-66% of total bacteria). Without ozonation, the community showed larger fluctuations, and Alphaproteobacteria emerged as dominant after 18 days (up to 54% of total bacteria). Ozonation of seawater also affected the dynamics of less abundant populations in the biofilm such as Betaproteobacteria, Planctomycetales and the Cytophaga/Flavobacterium branch of phylum Bacteroidetes. The abundance of Thiothrix, a bacterial genus capable of filamentous growth and fouling of larvae, increased with time for both water types, while no temporal trend could be detected for the genus Vibrio. Denaturing gradient gel electrophoresis (DGGE) demonstrated temporal changes in the dominant bacterial populations for both water types. Sequencing of DGGE bands confirmed the FISH data, and sequences were related to bacterial groups commonly found in biofilms of aquaculture systems. Several populations were closely related to organisms involved in sulfur cycling. Improved Artemia survival rates in tanks receiving ozonated water suggested a positive effect of ozonation on animal

  12. 封闭循环水养殖系统中池塘覆膜对水质的影响%Effects of covering membrane etange on water quality in a recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    李建国; 赵冬艳; 孙成渤

    2012-01-01

    In 2005 -2010, the water quality in the recirculating aquaculture system of Tianxiang Aquatic Co. Ltd was determined. The results displayed that the membrane and the area size of the membrane could change TH, AT, NH3 - N and PO4 - P of the whole aquaculture system in time and space. In time, there was extremely significant differences among different years ( P < 0. 01) ; in space, all the sampling points had remarkable differences in AT and NH3 -N ( P < 0. 05 ). Covering membrane etange reduced the stability of TH and AT in the aquaculture system, CV increased by 166. 5% ~241. 7%. This circumstance was particularly prominent in the medium of the culture process, but there was no obvious influence on the stability of NH3-N and PO4-P. For the indices of TH, AT and NH3-N, a large fraction of membrane covering in the aquaculture system (43. 7% ) was more variable than the non-covered etange ( CV elevated by 75. 86% for TH, 135. 6% for AT and 21. 6% for NH3-N) ; While the covered etange with a small covered area (19. 2% ) , was more stable than the non-covered etange (CV decreased by 71.9% for TH, 41.5% for AT and 91.4% for NH3-N). The reason for the above-mentioned differences in stability was attributed to the influence of membrane covering on substance interchange between the water and soil, as well as the biological activities within it.%2005-2010年,对天津市天祥水产有限公司封闭循环水养殖系统水质进行了检测.结果显示:养殖池塘是否覆膜、覆膜面积大小,均会使整个养殖系统中的总硬度(TH)、总碱度(AT)、NH3 -N和PO4-P在时空上产生差异.时间上,它们年份间差异极显著(P<0.01);空间上,各采样点的AT和NH3-N差异显著(P<0.05).覆膜使系统的TH和AT稳定性减弱,CV上升了166.5% ~ 241.7%,这种情况在养殖中期尤为突出,但对NH3-N和PO4-P 稳定性的影响并不明显.养殖系统中较大面积的覆膜(43.65%)对养殖池塘TH、AT和NH3-N稳定性的影响比非

  13. 海水循环水养殖系统生物脱氮技术研究进展%Research Advance in Biological Denitrification Technology for Seawater Circulative Aquaculture System

    Institute of Scientific and Technical Information of China (English)

    徐升

    2012-01-01

    Along with the gradual increase of marine products demand, in order to realize the sustainable development of fishery production, achieving the economic and effective denitrification effect was the key to the seawater recirculation. The paper overviewed the biological denitrification technologies in the seawater circulative aquaculture system, and summarized the common problems and solutions in the process of the denitrification, and the application of biological denitrification new technologies.%综述了海水循环水养殖系统生物脱氮工艺,并对脱氮过程中常见的问题、解决途径及生物脱氮新工艺的应用进行了探讨.

  14. 活化炉渣作为生物滤料在循环式海水工厂化养殖中的应用%The application of modified cinder as biological substrate in marine recirculating aquaculture systems

    Institute of Scientific and Technical Information of China (English)

    王际英; 乔洪金; 李宝山; 张利民; 陈玮; 宋向军

    2014-01-01

    为筛选适合于海水循环水养殖系统的高效价廉的生物滤料,研究了炉渣的活化方法,比较了活化炉渣与其它生物滤料在氨氮和亚硝酸盐氮处理效率上的差异,测定了活化炉渣生物包处理氨氮的速率,并在循环式海水工厂化养殖系统中检测了以活化炉渣填充的生物滤池去除营养盐的效果。结果显示,活化炉渣与常见生物滤料相比,在氨氮和亚硝酸盐氮处理效率上差异不显著(P<0.05);熟化的炉渣生物包处理氨氮的速率为4.21μg/( h·m2);以活化炉渣填充循环水养殖系统的生物滤池,经50 d熟化和处理后,养殖池内的氨氮浓度符合渔业水质标准。研究表明,活化炉渣是一种高效价廉的生物滤料,适合在循环式海水工厂化养殖中应用,但其发挥作用至少需要50 d的熟化。%To screen efficient and cheap biological substrate for marine recirculating aquaculture systems, in this paper, the modified method of cinder was studied, the removing efficiency of the ammonia and nitrite with modified cinder and other biological substrates were compared, and the treatment rate of ammonia with the maturated cinder package was determined as well. The removing efficiency of nutrient salts with bio-filter ponds containing modified cinder in marine recirculating aquaculture systems was also evaluated. The results showed that there was no significant difference in the removing efficiency of ammonia and nitrite( P<0.05) for modified cinder and other substrates. The treatment rate of ammonia by the maturated cinder package was 4. 21 μg/( h·m2 ) . When filling the bio-filter ponds in recirculating aquaculture systems with modified cinder, the concentrations of ammonia in culture ponds were comformed to the water quality standard for fisheries after 50 days maturation. Therefore, the modified cinder is an efficient and cheap biological substrate, and suitable for application in the

  15. Recycling Aquacultural Waste through Horticultural Greenhouse Production as a Resource Recovery Approach

    OpenAIRE

    Nair, Divya Sreelatha

    2006-01-01

    For intensive production systems like the Blue Ridge Aquaculture (BRA), based in Martinsville, VA, there are significant economic incentives to reuse the waste by diverting it into a cropping system that would increase the total productivity and total resource-reuse efficiency, and decrease the environmental, ecological, and financial costs of aquacultural waste disposal. In order to facilitate the reuse of effluent from the tilapia production at the BRA, a green house was developed. On this ...

  16. Temperature measurement systems in wearable electronics

    Science.gov (United States)

    Walczak, S.; Gołebiowski, J.

    2014-08-01

    The aim of this paper is to present the concept of temperature measurement system, adapted to wearable electronics applications. Temperature is one of the most commonly monitored factor in smart textiles, especially in sportswear, medical and rescue products. Depending on the application, measured temperature could be used as an initial value of alert, heating, lifesaving or analysis system. The concept of the temperature measurement multi-point system, which consists of flexible screen-printed resistive sensors, placed on the T-shirt connected with the central unit and the power supply is elaborated in the paper.

  17. Antimicrobial use and resistance in aquaculture: findings of a globally administered survey of aquaculture-allied professionals.

    Science.gov (United States)

    Tuševljak, N; Dutil, L; Rajić, A; Uhland, F C; McClure, C; St-Hilaire, S; Reid-Smith, R J; McEwen, S A

    2013-09-01

    There is limited published information regarding antimicrobial use (AMU) and antimicrobial resistance (AMR) in aquaculture. Our objective was to determine the opinions of aquaculture-allied professionals around the world on the frequency of AMU and AMR in common aquatic species. The study questionnaire included five sections: respondent demographics, extent of AMU in aquaculture, frequency of observations of AMR in aquaculture, AMR monitoring and surveillance and antimicrobial susceptibility testing in various jurisdictions. It was administered in English and Spanish to 604 professionals in 25 countries and with varying expertise in aquaculture. The response rate was 33% (199/604). Over half of the participants had >10 years of experience in aquaculture: 70% (140/199) were involved in fish health/clinical work and their primary experience was with salmon, tilapia, trout, shrimp (including prawn) and/or catfish. Tetracycline use was reported by 28%, 46%, 18%, 37% and 9% of respondents working with catfish, salmon, tilapia, trout and shrimp, respectively. Resistance to tetracycline in one or more species of bacteria was reported as 'frequent-to-almost always' for the same aquaculture species by 39%, 28%, 17%, 52% and 36% of respondents, respectively. 'Frequent-to-almost always' use of quinolone was reported by 70% (32/46) and 67% (8/12) of respondents from the United States and Canada, respectively, where quinolone products are not approved for aquaculture, and extra-label fluoroquinolone use is either prohibited (United States) or discouraged (Canada). Similar frequencies of quinolone use were also reported by the majority of respondents from Europe [70% (7/10)] and Asia [90% (9/10)] where labelled indications exist. This baseline information can be used to prioritize research or surveillance for AMU and AMR in aquaculture.

  18. Status of Irish Aquaculture 2003

    OpenAIRE

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2004-01-01

    This is the first joint report on the status of Irish aquaculture, which has been produced in collaboration by the three main State agencies that provide support services in the areas of research and development to the industry – Bord Iascaigh Mhara, the Marine Institute and Taighde Mara. The value of industry output was over €1 billion in the period from 1990 to 2003 and this represents a significant socio economic impact in the coastal areas of the south and west coast. The aims of the repo...

  19. Feed Additives for Aquaculture and Aquarium Culture

    OpenAIRE

    Barata, Eduardo N; Velez, Zélia

    2011-01-01

    The presente invention refers of feed additives for aquaculture and aquarium culture. These additives comprise the amino acid, 1-methyl-L-tryptophane, or its isomers with the objective of improving the attractiveness of feeds used in aquaculture and aquaria for fish, as well as other aquatic organisms, under culture conditions. Therefore, this invention has applications in the agriculture-food industry.

  20. World Aquaculture: Environmental Impacts and Troubleshooting Alternatives

    Directory of Open Access Journals (Sweden)

    Marcel Martinez-Porchas

    2012-01-01

    Full Text Available Aquaculture has been considered as an option to cope with the world food demand. However, criticisms have arisen around aquaculture, most of them related to the destruction of ecosystems such as mangrove forest to construct aquaculture farms, as well as the environmental impacts of the effluents on the receiving ecosystems. The inherent benefits of aquaculture such as massive food production and economical profits have led the scientific community to seek for diverse strategies to minimize the negative impacts, rather than just prohibiting the activity. Aquaculture is a possible panacea, but at present is also responsible for diverse problems related with the environmental health; however the new strategies proposed during the last decade have proven that it is possible to achieve a sustainable aquaculture, but such strategies should be supported and proclaimed by the different federal environmental agencies from all countries. Additionally there is an urgent need to improve legislation and regulation for aquaculture. Only under such scenario, aquaculture will be a sustainable practice.

  1. Microfluidic system for transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ring, Elisabeth A [ORNL; De Jonge, Niels [ORNL

    2010-01-01

    We present a microfluidic system that maintains liquid flow in a specimen chamber for (scanning) transmission electron microscope ((S)TEM) imaging. The specimen chamber consists of two ultra-thin silicon nitride windows supported by silicon microchips. They are placed in a specimen holder that seals the sample from the vacuum in the electron microscope, and incorporates tubing to and from the sample connected to a syringe pump outside the microscope. Using results obtained from fluorescence microscopy of microspheres flowing through the system, an equation to characterize the liquid flow through the system was calibrated. Gold nanoparticles of diameters of 30 and 100 nm moving in liquid were imaged with a 200 kV STEM. It was concluded that despite strong influences from Brownian motion, and sensitivity to small changes in the depth of the bypass channel, the electron microscopy flow data matched the calculated flow speed within an order of magnitude. The system allows for rapid (within a minute) liquid exchange, which can potentially be used, for example, to investigate the response of specimens, e.g., eukaryotic-, or bacterial cells, to certain stimuli.

  2. 40 CFR 122.25 - Aquaculture projects (applicable to State NPDES programs, see § 123.25).

    Science.gov (United States)

    2010-07-01

    ... of CWA, and in accordance with 40 CFR part 125, subpart B. (b) Definitions. (1) Aquaculture project... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Aquaculture projects (applicable to... DISCHARGE ELIMINATION SYSTEM Permit Application and Special NPDES Program Requirements § 122.25...

  3. Effects of Artificial Biological Purification System on Water Quality of Recirculating Aquaculture System%人工生物净化体系对循环水养殖系统水质的影响

    Institute of Scientific and Technical Information of China (English)

    李建国; 赵冬艳; 孙成渤

    2012-01-01

    In the recirculating aquaculture system, setting up the artificial purification system consisting of aquatic plants, cured indigenous microbial communities and filter-feeding fish and shellfish, can reduce the nutrients in the aquaculture water, lighten the eutrophication level and increase the stability of water quality effectively. Comparing the major water quality index before the system set up and those after that, the results show that in 2008 without the system, the average annual value of PO4-P, NH3-N, NO3-N, NO2-N and the phytoplankton gross in the purifying area were higher than that in the breeding area by 5.44 times, 1.35 times, 4.03 times, 2.55 times and 12.77 times, respectively. On the contrary, the data of the purifying area were lower than that of the breeding area by 122%, 146 %, 144%, 412% and 417%, respectively in 2009 with the system. In 2009, the economic aquatic plants absorbed the nutrient elements: N 0.208 8 kg, P 0.267 3 kg, K 0.022 5 kg in water and the filter-feeding fish and shellfish took 2 229.5 kg fish (shellfish) nutrients. The variation coefficient in the system of Alk, PO4-P, NH3-N, NO3-N, NO2-N and phytoplankton gross decreased by 8.43%, 26.98%, 62.33%, 17.01%, 0.01%, 35.55%, respectively compared with 2008.%循环水养殖系统中,建立以水生植物、固化了的土著微生物群落、滤食性鱼类及贝类等组成的人工净化体系可有效地降低养殖用水中的营养物质,减轻其富营养化程度,增加水质的稳定性。对比体系建立前后各主要水质指标的结果显示:未建立的2008年,净化区域的POrP、NH3-N、NO3-N、NO2-N、浮游植物总量的年均值分别比养殖区域高出5.44倍、1.35倍、4.03倍、2.55倍、12.77倍;而已建立该体系的2009年却相反,净化区域分别比养殖区域低了122%、146%、144%、412%、417%。2009年,水生经济植物吸收了水体中N0.2088kg、P0.2673kg、K0.0225妇的营养元素;

  4. Electronic Document Management Using Inverted Files System

    Science.gov (United States)

    Suhartono, Derwin; Setiawan, Erwin; Irwanto, Djon

    2014-03-01

    The amount of documents increases so fast. Those documents exist not only in a paper based but also in an electronic based. It can be seen from the data sample taken by the SpringerLink publisher in 2010, which showed an increase in the number of digital document collections from 2003 to mid of 2010. Then, how to manage them well becomes an important need. This paper describes a new method in managing documents called as inverted files system. Related with the electronic based document, the inverted files system will closely used in term of its usage to document so that it can be searched over the Internet using the Search Engine. It can improve document search mechanism and document save mechanism.

  5. Electronic Document Management Using Inverted Files System

    Directory of Open Access Journals (Sweden)

    Suhartono Derwin

    2014-03-01

    Full Text Available The amount of documents increases so fast. Those documents exist not only in a paper based but also in an electronic based. It can be seen from the data sample taken by the SpringerLink publisher in 2010, which showed an increase in the number of digital document collections from 2003 to mid of 2010. Then, how to manage them well becomes an important need. This paper describes a new method in managing documents called as inverted files system. Related with the electronic based document, the inverted files system will closely used in term of its usage to document so that it can be searched over the Internet using the Search Engine. It can improve document search mechanism and document save mechanism.

  6. Ferromagnetism in an Itinerant Electron System

    Institute of Scientific and Technical Information of China (English)

    D.F.WANG

    1996-01-01

    In this work.the ground states of the Hubbard model on complete graph are studied,for a finite lattice size L and arbitrary on-stie energy U.We construct explicitly the ground states of the system when the number of the electrons Ne≥L+1,In particular,for Ne=L+1,the ground state is ferromagnetic with total spin sg=(Ne-2)/2.

  7. Sustainable Treatment of Aquaculture Effluents—What Can We Learn from the Past for the Future?

    Directory of Open Access Journals (Sweden)

    Ariel E. Turcios

    2014-02-01

    Full Text Available Many aquaculture systems generate high amounts of wastewater containing compounds such as suspended solids, total nitrogen and total phosphorus. Today, aquaculture is imperative because fish demand is increasing. However, the load of waste is directly proportional to the fish production. Therefore, it is necessary to develop more intensive fish culture with efficient systems for wastewater treatment. A number of physical, chemical and biological methods used in conventional wastewater treatment have been applied in aquaculture systems. Constructed wetlands technology is becoming more and more important in recirculating aquaculture systems (RAS because wetlands have proven to be well-established and a cost-effective method for treating wastewater. This review gives an overview about possibilities to avoid the pollution of water resources; it focuses initially on the use of systems combining aquaculture and plants with a historical review of aquaculture and the treatment of its effluents. It discusses the present state, taking into account the load of pollutants in wastewater such as nitrates and phosphates, and finishes with recommendations to prevent or at least reduce the pollution of water resources in the future.

  8. BIOTECHNOLOGY OF THE FISH AQUACULTURE

    Directory of Open Access Journals (Sweden)

    L. P. Buchatsky

    2013-12-01

    Full Text Available The latest progress in biotechnology on fish aquaculture and different modern methods of investigations for increasing of fish productivity in aquaculture are analyzed. Except for the applied aspect, the use of modern biotechnological methods of investigations opens new possibilities for fundamental researches of sex-determining mechanisms, polyploidy, distant hybridization, and developmental biology of bony fishes. Review contains examples of utilizing modern biotechnology methods to obtain transgenic fishes with accelerated growth and for designing surrogate fishes. Methods for receiving unisexual shoals of salmon and sturgeon female fishes with the view of obtaining a large quantity of caviar, as well as receiving sterile (triploid fishes are analyzed. Great attention is given to androgenesis, particularly to disperm one, in connection with the problem of conserving rare and vanishing fish species using only sperm genetic material. Examples how distant hybrids may be obtained with the use of disperm androgenesis and alkylated DNA are given. Methods of obtaining fish primordium germ cells, recent developments in cultivation of fish stem cells and their use in biotechnology, as well as ones of transplantation of oogonium and spermatogonium to obtain surrogate fishes. The examples of successful experiments on spermatogonial xenotransplantation and characteristic of antifreezing fish proteins and also the prospect of their practical usage are given.

  9. Electronic document management systems: an overview.

    Science.gov (United States)

    Kohn, Deborah

    2002-08-01

    For over a decade, most health care information technology (IT) professionals erroneously learned that document imaging, which is one of the many component technologies of an electronic document management system (EDMS), is the only technology of an EDMS. In addition, many health care IT professionals erroneously believed that EDMSs have either a limited role or no place in IT environments. As a result, most health care IT professionals do not understand documents and unstructured data and their value as structured data partners in most aspects of transaction and information processing systems. PMID:12402630

  10. Gas supply system for the ''Electron'' installation

    International Nuclear Information System (INIS)

    The investigation results are described on a system for purifying and controlling the working gas of a helium streamer chamber operating on a bean of a electron linear accelerator. Maximum pressure in the system is 2 atm, and productivity at continuous helium circulation is 0.2 m2/hr. A chromatograph is used for determining the qualitative and quantitative composition of the gas. A gas-discharge cell is used for remote continuous control. Under operating conditions, the air impurity in the streamer chamber does not exceed 0.05%

  11. Novel phenomena in confined electronic systems

    Science.gov (United States)

    Roostaei, Bahman

    Modern experimental methods have made it possible for physicists to investigate matter in extreme conditions. Two of the most extreme conditions are low temperature and low dimensionality. Fabricated semiconductor or metal nano-ring arrays and narrow quantum wells in semiconductor heterostructures at low temperatures provide such an extreme environments for electrons. I will explain these systems in this dissertation. Quantum Wells. In a closely spaced double quantum well (DQW), electrons are thought to form an interlayer coherent state when a perpendicular magnetic field is applied such that the total Landau level filling factor one. The low energy topological excitations of the electron gas in these structures includes charged pseudo-spin vortices and anti-vortices. By calculating the energy per electron and the electron densities in the Hartree-Fock approximation, we show that there are new excited states with interwoven spin and pseudo-spin and that their presence in the system can explain new experimental results. The excitations of DQW's (called merons) also have important effects on transport in these systems. These objects carry charge, vorticity, and electric dipole moment. Disorder is likely to unbind them and allow them to diffuse through the system independently. Due to their different dipole moments, the various types of merons may then in principle be distinguished in transport activation energies by an interlayer bias potential. We explore the dynamics of merons using Chern-Simon theory for quantum Hall systems. We numerically estimate their energies in various circumstances and compare them to the recent experiments. Nano-rings. In this dissertation we also fully analyze the possible phases of a model of singly charged one and two dimensional arrays of rings each having a diameter " 100 nm. Using the Hartree approximation and Monte-Carlo simulations we demonstrate that the electrostatic polarization of these arrays undergoes a quantum phase

  12. The Application of Integrated Multi Trophic Aquaculture (IMTA Using Stratified Double Net Rounded Cage (SDFNC for Aquaculture Sustainability

    Directory of Open Access Journals (Sweden)

    Sapto P. Putro

    2015-12-01

    Full Text Available The increase of fishery production nationally and internationally may impact on the potential emergence of a variety of environmental problems. The application of sustainable aquaculture is urgently needed by breeding fish for commercial purposes in a manner such that it has a minimum impact on the environment, contributing to the development of local communities and generating economic benefits. The design of the cage and farming practice in aquaculture activities are the important steps to ensure that farming activity is still observed in order to anticipate the risk of organic enrichment caused by the activities. The application of Integrated Multi-Trophic Aquaculture  (IMTA on the Stratified Double Floating Net Cage  (SDFNC integrated with biomonitoring are an appropriate solution to the ongoing productive farming practices. IMTA is an aquaculture practice using more than one species of biotas which have ecologically mutual relationship as a part of the food chain in the area at the same time. The application of IMTA allows farmers to get several aquaculture products in the same area without increasing the horizontal area of the farms. At first, the SDFNC has been applied for farming Cyprinus carpio and Tilapia niloticus as polyculture system in freshwater ecosystem of Rawapening Lake, Central Java. Its operation has been able to increase the production capacity of at least 75% of conventional cages. The application of SDFNC-IMTA using milkfish (Chanos Chanos, seaweed (Kappaphycus alvarezii, and white shrimp (Litopenaeus vannamei has been able to minimize the impact and maintain the water ecosystem in the Gulf Awerange, South Sulawesi.

  13. Dynamically programmable electronic pill dispenser system.

    Science.gov (United States)

    Boquete, Luciano; Rodriguez-Ascariz, Jose Manuel; Artacho, Irene; Cantos-Frontela, Joaquin; Peixoto, Nathalia

    2010-06-01

    Compliance in medicine dispensation has proven critical for dosage control, diagnosis, and treatment. We have designed, manufactured, and characterized a novel dynamically programmable e-pill dispensing system. Our system is initially programmed remotely through a cell phone. After programming, the system may be reconfigured in order to adapt pill dispensation to new conditions. In this paper we describe the mechanics, electronics, control, and communication protocols implemented. Our dyn-e-pill devices can be actuated for over 350 h with two pill retrievals per hour. We challenged the charging circuit and demonstrated that the system has a lifetime longer than 6 h with a 30 min charging cycle, while it lasts for 14 h of uninterrupted use with a full charge. PMID:20503621

  14. Analysis of sedimentation and resuspension processes of aquaculture biosolids using an oscillating grid

    OpenAIRE

    Masaló Llorà, Ingrid; Guadayol, Oscar; Peters, Francesc; Oca Baradad, Joan

    2008-01-01

    Menció d'Honor 2010 que atorga l'Aquacultural Engineering Society Sedimentation and resuspension processes of aquaculture biosolids (non-ingested feed and faeces) are analysed using vertically oscillating grids as a source of turbulence in fluid tanks. An oscillating grid system consists of a container in which a grid is stirred vertically generating a well-known turbulent field that is function of amplitude and frequency of oscillation, distance between grid and measurement point, and mes...

  15. DIFFERENT PLANT DERIVED BY-PRODUCTS USE IN FRESHWATER AQUACULTURE IN INDIA

    OpenAIRE

    KAUSIK MONDAL

    2013-01-01

    As aquacultural practices increase in magnitude and hasten the flow ofmaterials and energy through the systems, compared to natural conditions, it stands toreason that many organic wastes can, save both monetary and caloric inputs into themodern aquaculture if these wastes are processed suitably and used as manure inincreasing productivity of the pond or as feed stuff to replace high cost ingredients in theformulation of diet for fish.

  16. Electronic integrated disease surveillance system and pathogen asset control system.

    Science.gov (United States)

    Wahl, Tom G; Burdakov, Aleksey V; Oukharov, Andrey O; Zhilokov, Azamat K

    2012-01-01

    Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS.Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA). PMID:23327375

  17. Electronic Integrated Disease Surveillance System and Pathogen Asset Control System

    Directory of Open Access Journals (Sweden)

    Tom G. Wahl

    2012-06-01

    Full Text Available Electronic Integrated Disease Surveillance System (EIDSS has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS.Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP sponsored by the US Defense Threat Reduction Agency (DTRA.

  18. Emergent behavior in strongly correlated electron systems

    Science.gov (United States)

    Pines, David

    2016-09-01

    I describe early work on strongly correlated electron systems (SCES) from the perspective of a theoretical physicist who, while a participant in their reductionist top-down beginnings, is now part of the paradigm change to a bottom-up ‘emergent’ approach with its focus on using phenomenology to find the organizing principles responsible for their emergent behavior disclosed by experiment—and only then constructing microscopic models that incorporate these. After considering the organizing principles responsible for the emergence of plasmons, quasiparticles, and conventional superconductivity in SCES, I consider their application to three of SCES’s sister systems, the helium liquids, nuclei, and the nuclear matter found in neutron stars. I note some recent applications of the random phase approximation and examine briefly the role that paradigm change is playing in two central problems in our field: understanding the emergence and subsequent behavior of heavy electrons in Kondo lattice materials; and finding the mechanism for the unconventional superconductivity found in heavy electron, organic, cuprate, and iron-based materials.

  19. Electronic key system using alpha detection

    International Nuclear Information System (INIS)

    We have developed the new electronic key system utilizes random pulse from alpha-particle detection with PIN photo diode. The random pulse by natural decay of alpha source is stable under the every outside environment like as temperature, pressure, an electromagnetic wave, and so on. The stable and un-predicted signals of the random pulses are the most suitable as a source of authentication signal for the electric key system. The program made of manufacture side forms the key code under current electronic key. Therefore, the manufacture must keep the code data secret for long time. The new electronic key always identify between key body and each key by the original pulse data from alpha particles. It is reduce the control cost of security remarkably. Moreover, back ground noise can be ignored in the circuit and it doesn't need to enlarge a total number of activity. The activity of the alpha source is about 10-100 Bq in one module. (author)

  20. Concepts of Highly Excited Electronic Systems

    Science.gov (United States)

    Berakdar, Jamal

    2003-05-01

    Knowledge of the excitation characteristics of matter is decisive for the descriptions of a variety of dynamical processes, which are of significant technological interest. E.g. transport properties and the optical response are controlled by the excitation spectrum. This self-contained work is a coherent presentation of the quantum theory of correlated few-particle excitations in electronic systems. It begins with a compact resume of the quantum mechanics of single particle excitations. Particular emphasis is put on Green function methods, which offer a natural tool to unravel the relations between the physics of small and large electronic systems. The book contains explicit expressions for the Coulomb Green function of two charge particles and a generalization to three-body systems. Techniques for the many-body Green function of finite systems are introduced and some explicit calculations of the Green functions are given. Concrete examples are provided and the theories are contrasted with experimental data, when available. The second volume presents an up-to-date selection of applications of the developed concepts and a comparison with available experiments is made

  1. 76 FR 9209 - Draft NOAA National Aquaculture Policy

    Science.gov (United States)

    2011-02-16

    ... National Aquaculture Policy and Draft DOC National Aquaculture Policy; Notices #0;#0;Federal Register / Vol... and Atmospheric Administration RIN 0648-XA214 Draft NOAA National Aquaculture Policy AGENCY: National...: Notice of availability of draft aquaculture policy; request for comments. SUMMARY: NOAA is seeking...

  2. Herion Servo techniques with electronic control systems in hydraulic systems

    Energy Technology Data Exchange (ETDEWEB)

    Ehrath, M.

    1981-01-01

    A description of an electro-hydraulic control circuit for the fuel pump and the injection valve of a large diesel engine is presented. Pressures of 500-1000 bar must be controlled in diesel engines. The newly-developed electronically controlled injection system uses quick-action control valves, a further developed version of the high-response valves. Electronically controlled ignition systems offer the following advantages: improved fuel-air ratio and better combustion; improved injection parameters within the total load range of the engine, better adaption to changing operational and environmental conditions and to changing fuel quality, fewer and less complicated components, and increased operational safety.

  3. Effects of alkalinity on ammonia removal, carbon dioxide stripping, and system pH in semi-commercial scale water recirculating aquaculture systems operated with moving bed bioreactors

    Science.gov (United States)

    When operating water recirculating systems (RAS) with high make-up water flushing rates in locations that have low alkalinity in the raw water, such as Norway, knowledge about the required RAS alkalinity concentration is important. Flushing RAS with make-up water containing low alkalinity washes out...

  4. REVIEW OF AQUACULTURE GENETIC RESEARCHES IN THAILAND

    Directory of Open Access Journals (Sweden)

    UTHAIRAT NA-NAKORN

    1992-01-01

    Full Text Available Aquaculture business has been well established in Thailand for more than 40 years. The most recent data indicated a total production of 260 380 tons. Sixty-five percent of the total production came from coastal aquaculture, mainly tiger prawn (Penaeus monodon culture. Other important species for coastal aquaculture are banana prawn (P. merguensis, cockle (Anadara granosa, green mussel (Perna viridis, oyster (Crassostrea belcheri, Saccostrea commercialis, sea bass (Lates calcarifer and grouper (Epinephelus tauvina. Freshwater aquaculture, although produced only 35% of the annual production, provides major protein source for people in rural areas. Important freshwater species are Nile tilapia (Oreochromis niloticus, tawes (Puntius gonionotus, sepat Siam (Trichogasterpectoralis, walking catfish (Glorias spp., stripped catfish (Pangasius sutchi and giant freshwater prawn (Macrobrachium rosenbergii. Optimum aquacultural practises, namely stocking density, nutrition requirement and water quality have been obtained in most cultured species. But genetic approach has not been considered, thus resulting in deterioration in economic traits which might be due to excessive inbreeding (reviewed by Uraiwan 1989 and/or negative selection (Wongsangchan 1985. The history of researches on genetics in aquaculture in Thailand started in 1982 when the aquaculture genetic programme in form of a network has been established at the National Inland Fisheries Institute, Department of Fisheries. This programme was supported by the International Development Research Centre (IDRC, Canada in cooperation with Dalhousie University, Canada (Uraiwan 1989. In the same year a genetic improvement programme aiming at improving economic characters of some economic fish species has been conducted at the Department of Aquaculture, Kasetsart University. Paralelly a course in Fish Genetics has been offered. Since then different approaches of genetics have been applied with final

  5. The EH101 Electronic Instrument Systems

    Directory of Open Access Journals (Sweden)

    Kieth N. Atkin

    1990-04-01

    Full Text Available This paper describes the background to the introduction of an electronic instrument system on the Anglo-Italian EH101 helicopter. The demanded flexibility to accommodate the display needs of several roles leading logically to the adoption of full colour multi-purpose display surfaces and the drive to achieve maximum commonality between military and civil variants is discussed. The configurations arrived at for both variants are described together with the operating philosophy and display formats developed during an ongoing simulator program. The paper also deals with a detailed description of the hardware implementation of the EIS including the fully integrated systems architecture and details of the symbol generators (SGs, display units (DUs and display mode selectors (DMSs. Emphasis is placed on the robust integrity characteristics and reversionary switching philosophy of the system."

  6. New Electron Gun System for BEPCII

    CERN Document Server

    Liu, Bo; Long Chi, Yun; Zhang, Chuang

    2005-01-01

    The new electron gun system for BEPCII has been put into operation since Nov. 2004. The article describes the design, experiment and operation of this new system. The design current of the gun is 10 A for the pulse lengths of 1 ns, 2.5 ns and 1 μs with repetition rate of 50 Hz. The gun is operated with a pulsed high voltage power supply which can provide up to 200 kV high voltage. Computer simulations have been carried out in the design stage, including simulation of the gun geometry and beam transportation. Some important relation curves are obtained during the experiment. Two-bunch operation is available and some elementary tests have been performed. New scheme of the gun control system based on EPICS is also presented. The real operation shows that the design and manufacturing is basically successful.

  7. Effect in water purification by airlift sand filter in aquaculture system%气提式砂滤器在水产养殖系统中的水质净化效果

    Institute of Scientific and Technical Information of China (English)

    于冬冬; 倪琦; 庄保陆; 张宇雷; 单建军; 管崇武; 张成林; 吴凡

    2014-01-01

    Traditional pressure sand filter after long time working intercepts large amounts of solid particles and leads to difficult backwash. In order to solve these problems, this study developed an airlift sand filter that can backwash itself while operating by optimizing a traditional filter. The airlift sand filter itself had filtration, separation, flotation, and self-cleaning functions, and could replace the traditional sand filters such as filter cell without valve, mechanical air flotation and other physical filtration device in aquaculture workshop. In the airlift sand filter, quartz sand (in diameter of 1-2 mm) was used as the filter medium, and the aquaculture sewage was flowed upward slowly from the bottom, thus quartz sand could intercept the suspended solids. Meanwhile, the fixed flow gas flowed from the bottom pushed dirt and quartz sand upwards simultaneously. During this process, sand and water were sufficiently contacted with each other. The interaction force between the sand and seawater resulted in production of a large number of bubbles. The suspended solids were then wrapped with the bubbles while quartz sand was cleaned by the sand washing device on the top of the system. The cleaned sand fallen back to the filter system by the gravity, and the suspended solids and waste water flowed out of the outfall. The airlift sand filter has the advantages of simple equipment, convenient operation, backwash without stopping the equipment, smooth and continuous system running, low energy consumption and easy to maintain and repair. The efficiency of the airlift sand filter used for marine recirculating aquaculture systems of the suspended solids (SS) and chemical oxygen demand (COD) was tested. Results showed that removal efficiency of SS and COD by this filter was 41.31%and 34.04%, respectively. Before the filtration, the number of large particles suspended solids (60 μm or higher) was 11.1%, its mass fraction was 71.77% and its mass concentration was 93.53 mg

  8. Study on estimation model of fish ammonia produce in recirculating aquaculture system%循环水养鱼系统中氨氮产生量估算模型的研究

    Institute of Scientific and Technical Information of China (English)

    刘晃; 顾川川

    2012-01-01

    循环水养鱼作为一种未来水产养殖的发展方向,其系统设计越来越受到关注,其中系统设计关键问题之一是快速去除水中的氨氮,因此准确得到氨氮产生量是系统设计中一个关键步骤.该研究基于物质平衡原理,同时假设每次投喂到鱼池中的饲料能及时地被养殖鱼摄食,并且养殖鱼排泄的粪便能在未被分解就快速排出系统,得到氨氮产生量的估算模型.该模型中氨氮产生量与循环水养殖系统的投喂量、饲料中蛋白质的含量和氮污染物的转化率成正比.在实际应用中该模型能较准确地估算出循环水养殖系统中的氨氮产生量,而且在考虑安全系数时,得到的估算值相比实际值大,符合工程设计中的系统安全需要.%Recirculating aquaculture is one of the development trends of the future aquaculture. And the system designs are being paid more and more attention. The key of system design is rapid removal of total ammonia-nitrogen. Therefore, the estimation model of fish total ammonia-nitrogen produce is important extremely to system design. Based on the material balance principle, the model to estimate the amount of total ammonia-nitrogen produced was established, assuming that feed have been eaten timely and faces have been removed from system before breaking. In this model, total ammonia-nitrogen produced increased with feeding rate, protein percentage of feed and nitrogen conversion rate. In practical application, the calculated values agree basically with those of actual operation. In consider with the safety factor, the results estimated were greater than actual values, which was accord with the system safety design needs.

  9. Electronic journal management systems experiences from the field

    CERN Document Server

    Ives, Gary W

    2013-01-01

    Discover how to manage your library's electronic journals?with tips from those who've already met the challenge!The explosive growth of electronic journals presents unique challenges for libraries. Electronic Journal Management Systems: Experiences from the Field comprehensively examines these complex topics, including explanations of the automated systems libraries have developed or adopted, licensing issues, and the provision of access to electronic journals. Respected library professionals discuss their own experiences in the implementation and use of electronic journal management systems,

  10. Electronic resource management systems a workflow approach

    CERN Document Server

    Anderson, Elsa K

    2014-01-01

    To get to the bottom of a successful approach to Electronic Resource Management (ERM), Anderson interviewed staff at 11 institutions about their ERM implementations. Among her conclusions, presented in this issue of Library Technology Reports, is that grasping the intricacies of your workflow-analyzing each step to reveal the gaps and problems-at the beginning is crucial to selecting and implementing an ERM. Whether the system will be used to fill a gap, aggregate critical data, or replace a tedious manual process, the best solution for your library depends on factors such as your current soft

  11. Structural dynamics of electronic and photonic systems

    CERN Document Server

    Suhir, Ephraim; Steinberg, David S

    2011-01-01

    The proposed book will offer comprehensive and versatile methodologies and recommendations on how to determine dynamic characteristics of typical micro- and opto-electronic structural elements (printed circuit boards, solder joints, heavy devices, etc.) and how to design a viable and reliable structure that would be able to withstand high-level dynamic loading. Particular attention will be given to portable devices and systems designed for operation in harsh environments (such as automotive, aerospace, military, etc.)  In-depth discussion from a mechanical engineer's viewpoint will be conducte

  12. 14 CFR 221.300 - Discontinuation of electronic tariff system.

    Science.gov (United States)

    2010-01-01

    ... of electronic tariff system. In the event that the electronic tariff system is discontinued, or the source of the data is changed, or a filer discontinues its business, all electronic data records prior to... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Discontinuation of electronic tariff...

  13. Controlling Underwater Robots with Electronic Nervous Systems

    Directory of Open Access Journals (Sweden)

    Joseph Ayers

    2010-01-01

    Full Text Available We are developing robot controllers based on biomimetic design principles. The goal is to realise the adaptive capabilities of the animal models in natural environments. We report feasibility studies of a hybrid architecture that instantiates a command and coordinating level with computed discrete-time map-based (DTM neuronal networks and the central pattern generators with analogue VLSI (Very Large Scale Integration electronic neuron (aVLSI networks. DTM networks are realised using neurons based on a 1-D or 2-D Map with two additional parameters that define silent, spiking and bursting regimes. Electronic neurons (ENs based on Hindmarsh–Rose (HR dynamics can be instantiated in analogue VLSI and exhibit similar behaviour to those based on discrete components. We have constructed locomotor central pattern generators (CPGs with aVLSI networks that can be modulated to select different behaviours on the basis of selective command input. The two technologies can be fused by interfacing the signals from the DTM circuits directly to the aVLSI CPGs. Using DTMs, we have been able to simulate complex sensory fusion for rheotaxic behaviour based on both hydrodynamic and optical flow senses. We will illustrate aspects of controllers for ambulatory biomimetic robots. These studies indicate that it is feasible to fabricate an electronic nervous system controller integrating both aVLSI CPGs and layered DTM exteroceptive reflexes.

  14. PROBLEMS OF BIOFOULING ON FISH–CAGE NETS IN AQUACULTURE

    OpenAIRE

    Merica Slišković; Gorana Jelić

    2002-01-01

    Biofouling on fish–cage netting is a serious technical and economical problem to aquaculture worldwide. Compensation for the effects of biofouling must be included in cage system design and planning, as fouling can dramatically increase both weight and drag. Settlements of sessile plants and animals, with accumulation of the detritus diminish the size of mesh and can rapidly occlude mesh. Negative effect of smaller mesh size is changing in water flow trough the cages. Biofouling problems nece...

  15. Identification of specific demands on Feed in Dutch Organic Aquaculture

    OpenAIRE

    Poelman, M.

    2009-01-01

    The evaluation of specific demands for organic feed focussed on feed demands for four fish species which can be cultured in Recirculation Aquaculture Systems (RAS), tilapia, African Catfish, shrimp and turbot. The evaluation of the various feed formulations indicates that there are several ingredients, which are common for the four species, and will therefore be used for further elaboration on the organic availability. These feed ingredients, are: fishmeal and oil, corn meal, wheat meal, bloo...

  16. Investigation and Study on the Alien Species in Aquaculture in the Lower Reaches of the Yangtze River

    Institute of Scientific and Technical Information of China (English)

    CHEN Jia-zhang; SHEN Gong-ming; MENG Shun-long; QU Jian-hong

    2011-01-01

    The lower reaches of the Yangze River is one of the central areas of freshwater shallow lakes in China and has the diverse climates with both warm temperate zone and sub-tropical zone,which makes it become one of the best areas for aquaculture,so nearly all of the aquaculture species from the world can live in the area.It is important for perfecting alien aquaculture species information data-base and environmental risk assessment system to investigate and study the aquaculture alien species in the lower reaches of the Yangze River.The results showed that the number of aquaculture alien species in the lower reaches of the Yangze River is 45 species,including 33 species of fishes,4 species of shellfish,7 species of crustaceans and 1 species of amphibian.Most of alien species are from America and the main transmitting way is intentional introducing.

  17. Radiation Risks and Mitigation in Electronic Systems

    CERN Document Server

    Todd, B

    2015-01-01

    Electrical and electronic systems can be disturbed by radiation-induced effects. In some cases, radiation-induced effects are of a low probability and can be ignored; however, radiation effects must be considered when designing systems that have a high mean time to failure requirement, an impact on protection, and/or higher exposure to radiat ion. High-energy physics power systems suffer from a combination of these effects: a high mean time to failure is required, failure can impact on protection, and the proximity of systems to accelerators increases the likelihood of radiation-induced events. This paper presents the principal radiation-induced effects, and radiation environments typical to high-energy physics. It outlines a procedure for designing and validating radiation-tolerant systems using commercial off-the-shelf components. The paper ends with a worked example of radiation-tolerant power converter controls that are being developed for the Large Hadron Collider and High Luminosity-Large Hadron Colli...

  18. Wigner-like crystallization of Anderson-localized electron systems with low electron densities

    CERN Document Server

    Slutskin, A A; Pepper, M

    2002-01-01

    We consider an electron system under conditions of strong Anderson localization, taking into account interelectron long-range Coulomb repulsion. We establish that at sufficiently low electron densities and sufficiently low temperatures the Coulomb electron interaction brings about ordering of the Anderson-localized electrons into a structure that is close to an ideal (Wigner) crystal lattice, provided the dimension of the system is > 1. This Anderson-Wigner glass (AWG) is a new macroscopic electron state that, on the one hand, is beyond the conventional Fermi glass concept, and on the other hand, qualitatively differs from the known 'plain' Wigner glass (inherent in self-localized electron systems) in that the random slight electron displacements from the ideal crystal sites essentially depend on the electron density. With increasing electron density the AWG is found to turn into the plain Wigner glass or Fermi glass, depending on the width of the random spread of the electron levels. It is shown that the res...

  19. Intelligent monitoring system for aquaculture dissolved oxygen in pond based on wireless sensor network%基于无线传感器网络的水产养殖池塘溶解氧智能监控系统

    Institute of Scientific and Technical Information of China (English)

    马从国; 赵德安; 王建国; 陈亚娟; 李亚洲

    2015-01-01

    In order to facilitate DO (dissolved oxygen) monitoring for a scaled aquaculture pond, a DO intelligent monitoring system was developed based on a wireless sensor network, which could realize distribution measurement, intelligent control, and centralized management. The system consists of a three-layer structure including data acquisition and control, water quality monitoring, and water management. The data acquisition and control layer was composed of data acquisition and control terminals, routing nodes, and a coordinator node based on ZigBee technology. They were deployed in the sensing area for an aquaculture pond’s waters, and they constituted a wireless monitoring network for water quality environmental parameters by self organization to collect water quality parameters and adjust control devices. The water quality monitoring layer included a water quality monitoring terminal and a communication computer, which realized water quality supervision and aquaculture equipment intelligent control. The water quality management layer contained mainly a water quality management terminal, a system database, and a Web server end. The water quality management end was responsible for analysis and processing for the water quality data. The monitoring system concentrated wireless data acquisition, intelligent control, and centralized management for water quality parameters to improve scale aquaculture benefit and information management level. Aiming at low adaptive ability for conventional fuzzy PID controller, a variable universe fuzzy PID controller was proposed, which comprises an adjustment unit for expansion factors, variable universe fuzzy control unit and PID controller, the extension factorα1,α2 andβfor input and output domain of fuzzy control unit were adjusted constantly by an expansion factor regulating unit according to DO error and DO error change rate. PID controller parameters were tuned online by a variable universe fuzzy control unit to realize the

  20. 抽屉式生物滤器在漠斑牙鲆循环水养殖中的效果研究%The purification effect of drawer biofilter in recirculating aquaculture system for southern flounder

    Institute of Scientific and Technical Information of China (English)

    秦继辉; 孙建明; 班同; 徐哲; 吴垠

    2012-01-01

    A self-designed drawer biofilter used in recirculating aquaculture system for Paralichthys lethostigma,the research is about the water treatment effect of drawer biofilter,weight gain and feed utilization rate.The results show that the P.lethostigma (225.4 ± 11.9) g during follow-up of 60 days culture in recirculating system gets a weight gain rate of 49.97% (337.5 ±10.3) g,the feed coefficient of 1.06,rearing density reaches 24.1 kg/ m3 and survival rate amounts to 100%.The removal efficiencies of drawer biofdter about NH4+ -N、NO2- -N and COD are (10.61 ±1.88)%,(14.90 ±3.06)% and (16.11 ±1.704)%,respectively.Therefore,using drawer biofilter to breed P.lethostigma in recirculating aquaculture system is feasible.%采用自行设计的抽屉式生物滤器应用于漠斑牙鲆(Paralichthys lethostigma)闭合循环水养殖系统,研究其对循环养殖水的处理效果及漠斑牙鲆的增重和饲料利用率的影响.结果表明:经过60 d的循环水养殖,漠斑牙鲆从初始时的(225.41±11.9)g增加到结束时的(337.5±10.3)g,增重率49.97%;试验饲料系数1.06,养殖密度24.1kg/m3,成活率100%;抽屉式生物滤器对于NH4+-N、NO2- -N和COD去除率分别为(10.61±1.88)%、(14.90±3.06)%和(16.11±1.70)%,可满足漠斑牙鲆养殖水体的水质要求.

  1. Reproduction of European Eel in Aquaculture (REEL)

    DEFF Research Database (Denmark)

    Tomkiewicz, Jonna; Tybjerg, Lars; Støttrup, Josianne;

    Project aim: Enhance methods and technology applied to produce and culture European eel larvae as basis for the development of a future self-sustained eel aquaculture. Background: The severe decline of the European eel stock calls for conservation measures including national eel management plans...... and establishment of a self-sustained eel aquaculture. In 2005, the National Institute of Aquatic Resources at the Technical University of Denmark (DTU Aqua), the Faculty of Life Sciences at Copenhagen University (KU-Life) and the eel aquaculture industry started to build up a research and technology platform...... for the development of methods to reproduce European eel in aquaculture. Two major projects: Artificial Reproduction of Eels II and III (ROE II and III) succeeded during 2005-2008 to produce viable eggs and larvae that lived up to 12 days. The larvae thereby accomplished the yolk-sac stage and became ready to start...

  2. Aquaculture in Coastal and Marine US Waters

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, mollusks, and aquatic plants. The presence and location of...

  3. Liposarcoma in clownfish, Amphiprion ocellaris Cuvier, produced in indoor aquaculture.

    Science.gov (United States)

    Sharon, G; Benharroch, D; Kachko, L; Reis-Hevlin, N; Zilberg, D

    2015-06-01

    Clownfish, Amphiprion ocellaris Cuvier, produced and grown in an experimental indoor aquaculture facility, presented with lipomatous tumours. A total of 14 affected fish were examined. Based on the total number of fish at the aquaculture facility at the time of outbreak of this pathology, the scope of the incident is estimated to be 1 of 300 fish. The tumours were characterized by the presence of mature adipocytes of variable sizes, lipoblasts and by an invasive behaviour, which affected internal organs, muscle, central nervous system and, in one case, an eye. Detailed macroscopic and histopathological features are presented. The suggested diagnosis is that of a well-differentiated liposarcoma, a diagnosis so far never applied to fish. The limited outbreak of the neoplasm lasted a few months in 2011 and did not recur. Possible factors leading to this phenomenon, notably the metastasis, are discussed.

  4. Carbon dioxide stripping in aquaculture. part 1: terminology and reporting

    Science.gov (United States)

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    The removal of carbon dioxide gas in aquacultural systems is much more complex than for oxygen or nitrogen gas because of liquid reactions of carbon dioxide and their kinetics. Almost all published carbon dioxide removal information for aquaculture is based on the apparent removal value after the CO2(aq) + HOH ⇔ H2CO3 reaction has reached equilibrium. The true carbon dioxide removal is larger than the apparent value, especially for high alkalinities and seawater. For low alkalinity freshwaters (<2000 μeq/kg), the difference between the true and apparent removal is small and can be ignored for many applications. Analytical and reporting standards are recommended to improve our understanding of carbon dioxide removal.

  5. 循环水养殖系统培育日本鳗鲡和美洲鳗鲡苗种的研究%Studies on fingerlings breeding of Anguilla japonica and Anguilla rastrata by recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    徐继松; 关瑞章; 陈学豪; 赖晓健

    2012-01-01

    采用具有气泡反冲洗型珠子过滤器的循环水养殖系统对日本鳗鲡和美洲鳗鲡进行了苗种培育的研究.2种鳗苗的放养密度约为传统模式的8~10倍,试验期间换水量约为20%~45%.结果显示:日本鳗苗和美洲鳗苗成活率均≥96.74%,高于传统模式.投喂水丝蚓阶段,日本鳗苗特定生长率和饲料系数分别为(7.08±0.08)%/d和4.92±0.03,美洲鳗苗分别为(4.83±0.06)%/d和4.74+0.19.投喂配合饲料阶段,日本鳗苗分别为(2.30±0.19)%/d和1.30±0.02,美洲鳗苗分别为(1.69±0.05)%/d和1.76±0.06.研究表明,该循环水养殖系统可适用于日本鳗苗和美洲鳗苗的培育,并具有节能、减排和无药残等优点,为开发资源节约型和环境友好型的鳗鲡育苗模式提供参考.%Anguilla japonica and A.rastrata fingerlings were bred by the recirculating aquaculture system which has the bubble bead filter.The stocking density of this experiment was 8-10 times more than the model of traditional culture.The quantity of the exchanged water was 20% 45% during the experimental period.The results showed that the survival rates of A.japonica and A.rastrata fingerlings were all above 96.74%,and higher than the model of traditional culture.The specific growth rates ( SGR) and feed conversion ratioes (FCR) of A.japonica and A.rastrata fingerlings were (7.08 ±0.08)%/d and (4.83 ±0.06)%/d,4.92± 0.03 and 4.74 ±0.19,respectively,during the period of feeding Limnodrilus hoffmeisteri.The SGR and FCR oiA.japonica and A.rastrata fingerlings were (2.30 ±0.19)%/d and (1.69 ±0.05)%/d,1.30±0.02 and 1.76 ±0.06,respectively,during the period of feeding compound diet.The results indicated that the recirculating aquaculture system was suitable for the fingerlings breeding of A.japonica and A.rastrata.The fingerlings breeding of eel were energy-saving,emission reduction and non-residue by the recirculating aquaculture system.These results will provide an important

  6. Educational Systems Design Implications of Electronic Publishing.

    Science.gov (United States)

    Romiszowski, Alexander J.

    1994-01-01

    Discussion of electronic publishing focuses on the four main purposes of media in general: communication, entertainment, motivation, and education. Highlights include electronic journals and books; hypertext; user control; computer graphics and animation; electronic games; virtual reality; multimedia; electronic performance support;…

  7. 复合人工湿地-池塘养殖生态系统细菌多样性研究%Bacterial Diversity Investigation on an Integrated System of Constructed Wetland and Pond Aquaculture

    Institute of Scientific and Technical Information of China (English)

    姚延丹; 李谷; 陶玲; 李晓莉; 张世羊; 赵巧玲; 林玉良

    2011-01-01

    The bacterial diversity investigation in the integrated system of constructed wetland and pond aquaculture was carried out during the period of Aug.-Oct. 2009, using analytic method of DGGE (denatured gradient gel electrophoresis). The findings presented that temperature and DO of the culture ponds changed over the investigation period, and both bacterial density and diversity in the culture pond varied with change of the season; in addition, the levels of NH4 and TP in the control pond were significantly higher (p<0.05) than those in the recirculation ponds. Correlation analysis pertaining to the investigation revealed that bacterial diversity was remarkably and positively correlated with DO, but negatively with NHJ and TP. It was concluded that the pond-recirculation aquaculture could enhance bacterial diversity in the ponds thus the pond system became more stable ecologically.%于2009年8至10月对比调查研究了由人工湿地-池塘养殖复合构成的池塘循环水养殖系统和传统池塘养殖系统中水体理化和生物特征,并利用变性梯度凝胶电泳技术(DGGE)分析了两系统中的细菌多样性。研究结果表明:试验期间各池塘水温和溶氧随月份呈下降趋势,对照塘NH4+-N和TP显著高于循环塘(P<0.05),而循环塘间无显著差异;各池塘细菌丰度和多样性指数均呈季节性变化,对照塘细菌丰度高于循环塘,且波动明显,而多样性指数却低于循环塘,细菌群落结构趋于简单;循环塘的细菌多样性指数逆水流方向呈增加趋势,P2塘较P4受循环水流的调控作用稍大。相关分析表明,细菌多样性指数与DO显著正相关,与NH4+-N、TP负相关。因此,池塘循环水养殖能够提高水体中细菌的生物多样性,相应池塘生态系统更具稳定性。

  8. Design and construction technology of water-purifying facilities in recirculating aquaculture system%循环水养殖系统水质净化设施设计与建造技术

    Institute of Scientific and Technical Information of China (English)

    赵景丽; 王际英; 张利民; 曹体宏; 李宝山; 乔洪金

    2013-01-01

      水质净化设施具有投资小、运行能耗低和单位处理量大等优点,适合国内现阶段循环水养殖的普及和推广。本文介绍了沉淀池、气浮池和生物滤池三种水质净化设施的设计及建造中的关键技术。在系统正常运行的条件下,养殖水体的pH值维持在7.5以下,非离子氨、亚硝氮和磷的含量分别维持在5.60~7.96μg/L、0.08~0.10 mg/L和2.12~2.52 mg/L范围内。结果表明,系统对水体pH控制合理,对氨氮处理效果较为理想。综合分析可知,该循环水养殖系统水处理工艺和水质净化设施设计合理,能够较好的满足使用需求。%  Water-purifying facilities are suitable for popularization and promotion at present stage in China with small investment, running low energy consumption and large unit processing advantages .In this paper, three kinds of water-purifying facilities were introduced:sedimentation tank, flotation tank and biofilter.The key technologies in design and construction process were summarized .Under the normal running condition , pH in aquaculture water was maintained below 7.5.Non-ionic ammonia, nitrite nitrogen and phosphorus were maintained at the range of 5.60-7.96 μg/L, 0.08-0.10 mg/L and 2.12-2.52 mg/L, respectively.The results showed that the control of pH and treatment effect of ammonia nitrogen in the system were good .It is proved that the design of the recirculating aquaculture system and water-purifying facilities are reasonable, which could better meet the use requirements .

  9. Bioactivity of phytochemicals in some lesser-known plants and their effects and potential applications in livestock and aquaculture production systems.

    Science.gov (United States)

    Makkar, H P S; Francis, G; Becker, K

    2007-10-01

    Livestock and aquaculture production is under political and social pressure, especially in the European Union (EU), to decrease pollution and environmental damage arising due to animal agriculture. The EU has banned the use of antibiotics and other chemicals, which have been shown to be effective in promoting growth and reducing environment pollutants because of the risk caused to humans by chemical residues in food and by antibiotic resistance being passed on to human pathogens. As a result of this, scientists have intensified efforts in exploiting plants, plant extracts or natural plant compounds as potential natural alternatives for enhancing the livestock productivity. This paper discusses work on the effects of various phytochemicals and plant secondary metabolites in ruminant and fish species. The focus is on (i) plants such as Ananas comosus (pine apple), Momordica charantia (bitter gourd) and Azadirachta indica (neem) containing anthelmintic compounds and for their use for controlling internal parasites; (ii) plants containing polyphenols and their applications for protecting proteins from degradation in the rumen, increasing efficiency of microbial protein synthesis in rumen and decreasing methane emission; for using as antioxidants, antibacterial and antihelmintic agents; and for changing meat colour and for increasing n-3 fatty acids and conjugated linoleic acid in meat; (iii) saponin-rich plants such as quillaja, yucca and Sapindus saponaria for increasing the efficiency of rumen fermentation, decreasing methane emission and enhancing growth; for producing desired nutritional attributes such as lowering of cholesterol in monogastric animals; for increasing growth of fish (common carp and Nile tilapia) and for changing male to female ratio in tilapia; and for use as molluscicidal agents; (iv) Moringa oleifera leaves as a source of plant growth factor(s), antioxidants, beta-carotene, vitamin C, and various glucosinolates and their degraded products for

  10. CERN Sells its Electronic Document Handling System

    CERN Document Server

    2001-01-01

    The EDH team. Left to right: Derek Mathieson, Rotislav Titov, Per Gunnar Jonsson, Ivica Dobrovicova, James Purvis. Missing from the photo is Jurgen De Jonghe. In a 1 MCHF deal announced this week, the British company Transacsys bought the rights to CERN's Electronic Document Handling (EDH) system, which has revolutionised the Laboratory's administrative procedures over the last decade. Under the deal, CERN and Transacsys will collaborate on developing EDH over the coming 12 months. CERN will provide manpower and expertise and will retain the rights to use EDH, which will also be available freely to other particle physics laboratories. This development is an excellent example of the active technology transfer policy CERN is currently pursuing. The negotiations were carried out through a fruitful collaboration between AS and ETT Divisions, following the recommendations of the Technology Advisory Board, and with the help of SPL Division. EDH was born in 1991 when John Ferguson and Achille Petrilli of AS Divisi...

  11. Application of Constructed Wetlands on Wastewater Treatment for Aquaculture Ponds

    Institute of Scientific and Technical Information of China (English)

    LI Gu; WU Zhenbin; CHENG Shuiping; LIANG Wei; HE Feng; FU Guiping; ZHONG Fei

    2007-01-01

    A group of constructed wetlands (CWs) were applied to the recirculating aquaculture system. This study assessed the performance of CWs in treating the aquaculture wastewater, examined the water quality condition of aquaculture ponds and the growth and the survival rate of "target" species(Ictalurus punctatus and Megalobrama amblycephala). The results showed that CWs were effective on reducing the concentrations of 5-day biochemical oxygen demand (BOD5, at 70.5%), total suspended solids (TSS, at 81.9%),chlorophyll a (Chl-a, at 91.9%), ammonium (NH4+, at 61.5%) and nitrate nitrogen (NO3--N, at 68.0%). Effect of CWs on phosphate (PO43- -P) removal was relatively lower (at 20.0%). The concentrations of BOD5, TSS, Chl-a, NH4+ and TN, TP in the recirculating culture pond were significantly lower than that in the control pond( p < 0.05 ). CWs could help to increase total yield, survival rate of the "target" species and significantly decrease feed conversion ratio ( p < 0.05 ).

  12. Ammonia Processing Technology in A Recirculating System in Industrial Aquaculture:A Review%工厂化水产养殖水中氨氮处理技术的研究

    Institute of Scientific and Technical Information of China (English)

    韩世成; 郭常有; 蒋树义; 曹广斌

    2014-01-01

    氨氮处理技术是工厂化水产养殖的关键技术之一。本文综述国内外工厂化养殖中常用的氨氮处理方法,如空气吹脱、离子交换吸附、微生物处理、臭氧氧化处理、沉水植物处理等,分析各种方法的优缺点,论证LED特定光照沉水植物处理氨氮方法的优势、可行性和发展方向,为实际应用和新技术开发提供参考。%Ammonia processing technology as a key in a recirculating aquaculture system is summarized including a bubble-washed bead filter, ion exchange and adsorption, microorganism treatment, and use of ozone and submerged plants. The advantages and disad-vantages of these methods are evaluated, and a new method, specific LED light irradiation submerged plants handling ammonia, is in-troduced. The future researches on those methods are discussed to provide a base for practice application.

  13. Real-Time Water Quality of Aquaculture Monitoring System Based on the Internet of Things%基于物联网的水产养殖水质实时监测系统①

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      为了实现水产养殖水质的实时监测和信息化管控,以 ZigBee、GPRS、智能水质监测传感器等物联网核心技术为手段,设计了一套水产养殖水质实时监测系统,能实时采集水产养殖用水的水位、溶解氧、PH 值、温度、视频等参数,并进行分析、展示和反馈控制,从而解决了水产养殖业水质实时监测和管理问题。%In order to realize the real time monitor and informatization management of the water quality of aquaculture industry, the water quality monitoring system was designed based on the core technology of the internet of things such as:ZigBee, GPRS and the sensor technology for real-time water quality monitoring. The water level, dissolved oxygen, the temperature and video parameters could be collected in real time, analyzed, displayed and managed.

  14. Development of the electron gun control system of SSRF

    International Nuclear Information System (INIS)

    An electron gun is the key part of a linac, the beam quality of which depends on beam quality of the electron gun, hence the need of a stable control system of the electron gun to ensure its safe operation.In this paper, we report our progresses in developing the linac's electron gun control system of Shanghai Synchrotron Radiation Facility (SSRF). It uses PLC as the device controllers, with the monitoring software developed on EPICS. The whole system is connected by Ethernet. The PLC and Ethernet technology ensures good reliability and easy maintenance of the electron gun control system. (authors)

  15. Aquaculture, husbandry, and shipping at the Zebrafish International Resource Center.

    Science.gov (United States)

    Varga, Z M

    2016-01-01

    This chapter provides an overview of the Zebrafish International Resource Center (ZIRC) aquaculture systems, husbandry, and live fish shipping methods. The ZIRC has a recirculating water system with mechanical and biological filtration in its main fish facility, and a flow-through water system for its quarantine room. I describe basic husbandry methods for breeding, rearing larvae, feeding and shipping of fish. Whereas the procedures presented here are merely an overview and only the most essential methods are included, they offer starting points to set up, develop, refine, or troubleshoot methods in other fish facilities. PMID:27443942

  16. Aquaculture and husbandry at the zebrafish international resource center.

    Science.gov (United States)

    Varga, Zoltán M

    2011-01-01

    This chapter provides an overview of the aquaculture system and the husbandry methods used at the Zebrafish International Resource Center (ZIRC). ZIRC employs a recirculating water system with mechanical and biological filtration for its main facility, and a flow-through water system for its quarantine room. I describe basic husbandry methods for breeding, rearing larvae, and feeding and the extensive in-house health surveillance for the biosafety of the fish population. Whereas the description of these procedures is merely an overview and only the most essential methods are included, it offers several starting points to set up, refine, or troubleshoot other fish facilities. PMID:21924177

  17. 复合池塘循环水养殖系统微生物群落结构分析%Analysis of microbial community structure in an integrated pond recirculating aquaculture system

    Institute of Scientific and Technical Information of China (English)

    姚延丹; 李谷; 陶玲; 李晓莉; 张世羊; 赵巧玲; 林玉良

    2011-01-01

    于2008年6至10月逐月调查研究了新型复合池塘循环水养殖系统各塘水体理化和微生物分子特征.通过提取水样中细菌总DNA,扩增其16S rDNA基因V3区,再经DGGE分析获得图谱,选择其中主要的13条特征条带进行克隆测序.研究结果表现为,随水流方向(Pl→P5),各循环塘溶氧(DO)和透明度(SD)依次呈明显下降趋势,而NH4~+-N,TP和COD_Mn水平呈明显上升趋势;与对照塘相比,循环塘DO和SD升高,COD_Mn和营养盐水平降低.DGGE图谱分析显示,各养殖塘微生物种类丰富,循环塘与对照塘的群落结构存在明显差异,且差异主要表现在较弱的条带上;13条特征条带的测序结果表明,池塘优势菌群分属4个门:放线菌门(Actinobacteria)、变形菌门(Proteobacteria)、蓝细菌门(Cyanobacteria)和拟杆菌门(Bacteroidetes),其中有2条属于蓝细菌门的条带特定分布于对照塘.典型对应分析(CCA)排序结果显示,DGGE图谱条带分布与理化因子密切相关.与传统池塘养殖相比,该养殖模式有助于改善养殖池塘微生态环境.本研究旨为池塘微生物群落结构及其功能关系研究提供借鉴.%Aquaculture has been one of the fastest growing segments of global food production sector in recent decades. With the rapid development, it also leads to many environmental problems. For example, both per unit area yield of aquatic products and their quality has declined continuously.It is important that well-balanced systems be developed that are sustainable. Constructed wetlands (CWs) are ecologically beneficial, low-cost treatment alternatives, proven capable of reducing suspended solids, 5-day biochemical oxygen demand (BOD5), nitrogen, phosphorus and heavy metals from wastewater of many sources. In the present paper, the physicochemical and microbial characteristics of culture ponds in an Integrated Pond Recirculating Aquaculture System (IPRAS)based on constructed wetland were investigated during the period

  18. Power electronic converters and systems frontiers and applications

    CERN Document Server

    Trzynadlowski, Andrzej M

    2016-01-01

    Power electronics is a branch of electrical engineering dealing with conversion and control of electric power using semiconductor power switches. This book provides an overview of modern power electronic converters and systems, and their applications.

  19. Magnetic ordering in strongly correlated-electron uranium systems: Consequences of two kinds of f-electron-band-electron states

    Science.gov (United States)

    Cooper, Bernard R.; Lin, Yeong-Lieh; Sheng, Qing-Guang

    1999-04-01

    Magnetic ordering involves the electronic behavior globally; and for uranium-based systems, the hybridization-induced effects dominate over the Coulomb exchange effects in determining the magnetic ordering. Therefore, as long as the hybridization is treated as acting between properly exchange-symmetrized two-electron wave functions, the effects of exchange can be incorporated in the one-electron exchange-correlation potential. As a consequence of the necessary exchange symmetrization, there are essentially two kinds of f electrons, localized magnetic and itinerant nonmagnetic. This has enabled us to make absolute material-specific predictions of alloying or high-pressure effects on magnetic ordering in uranium strongly correlated-electron (SCE) systems using local-density approximation input into many-electron dynamics. Experimentally, the alloying effects can be dramatic, e.g., in UxLa1-xS the magnetic ordering abruptly disappears at about 55% uranium. The theory is quite successful in its detailed absolute predictions, and this has important implications for the overall understanding of electronic behavior in SCE systems including heavy fermion systems. The key conclusion is that strengthening the hybridization, as kinematically restricted by exchange symmetry, leads to a chemical-environment-dependent sharp phase transition in SCE systems with dramatic observable consequences. This phase transition is associated with the elimination of the localized-magnetic transition-shell electrons (f electrons for light actinide and cerium-based SCE materials, d electrons for transition-metal-oxide-based SCE materials).

  20. Advanced Photonic and Electronic Systems WILGA 2010

    CERN Document Server

    Romaniuk, R S

    2010-01-01

    SPIE – PSP WILGA Symposium gathers two times a year in January and in May new adepts of advanced photonic and electronic systems. The event is oriented on components and applications. WILGA Symposium on Photonics and Web Engineering is well known on the web for its devotion to “young research” promotion under the eminent sponsorship of international engineering associations like SPIE and IEEE and their Poland Sections or Counterparts. WILGA is supported by the most important national professional organizations like KEiT PAN and PSP-Photonics Society of Poland. The Symposium is organized since 1998 twice a year. It has gathered over 4000 young researchers and published over 2000 papers mainly internationally, including more than 900 in 10 published so far volumes of Proc. SPIE. This paper is a digest of WILGA Symposium Series and WILGA 2010 summary. Introductory part treats WILGA Photonics Applications characteristics over the period 1998-2010. Following part presents a short report on the XXVth and XXVI...