WorldWideScience

Sample records for aquaculture enclosures relate

  1. Material containment enclosure

    International Nuclear Information System (INIS)

    Carlson, D.O.

    1993-01-01

    An isolation enclosure and a group of isolation enclosures are described which are useful when a relatively large containment area is required. The enclosure is in the form of a ring having a section removed so that a technician may enter the center area of the ring. In a preferred embodiment, an access zone is located in the transparent wall of the enclosure and extends around the inner perimeter of the ring so that a technician can insert his hands into the enclosure to reach any point within. The inventive enclosures provide more containment area per unit area of floor space than conventional material isolation enclosures. 3 figures

  2. 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...

  3. Large-scale climatic effects on traditional Hawaiian fishpond aquaculture.

    Directory of Open Access Journals (Sweden)

    Daniel McCoy

    Full Text Available Aquaculture accounts for almost one-half of global fish consumption. Understanding the regional impact of climate fluctuations on aquaculture production thus is critical for the sustainability of this crucial food resource. The objective of this work was to understand the role of climate fluctuations and climate change in subtropical coastal estuarine environments within the context of aquaculture practices in He'eia Fishpond, O'ahu Island, Hawai'i. To the best of our knowledge, this was the first study of climate effects on traditional aquaculture systems in the Hawaiian Islands. Data from adjacent weather stations were analyzed together with in situ water quality instrument deployments spanning a 12-year period (November 2004 -November 2016. We found correlations between two periods with extremely high fish mortality at He'eia Fishpond (May and October 2009 and slackening trade winds in the week preceding each mortality event, as well as surface water temperatures elevated 2-3°C higher than the background periods (March-December 2009. We posit that the lack of trade wind-driven surface water mixing enhanced surface heating and stratification of the water column, leading to hypoxic conditions and stress on fish populations, which had limited ability to move within net pen enclosures. Elevated water temperature and interruption of trade winds previously have been linked to the onset of El Niño in Hawai'i. Our results provide empirical evidence regarding El Niño effects on the coastal ocean, which can inform resource management efforts about potential impact of climate variation on aquaculture production. Finally, we provide recommendations for reducing the impact of warming events on fishponds, as these events are predicted to increase in magnitude and frequency as a consequence of global warming.

  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. PMID:22649291

  5. 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.

  6. Potential drivers of virulence evolution in aquaculture

    Science.gov (United States)

    Kennedy, David A.; Kurath, Gael; Brito, Ilana L.; Purcell, Maureen K.; Read, Andrew F.; Winton, James R.; Wargo, Andrew R.

    2016-01-01

    Infectious diseases are economically detrimental to aquaculture, and with continued expansion and intensification of aquaculture, the importance of managing infectious diseases will likely increase in the future. Here, we use evolution of virulence theory, along with examples, to identify aquaculture practices that might lead to the evolution of increased pathogen virulence. We identify eight practices common in aquaculture that theory predicts may favor evolution toward higher pathogen virulence. Four are related to intensive aquaculture operations, and four others are related specifically to infectious disease control. Our intention is to make aquaculture managers aware of these risks, such that with increased vigilance, they might be able to detect and prevent the emergence and spread of increasingly troublesome pathogen strains in the future.

  7. 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.

  8. 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.

  9. Environmental impact of aquaculture and countermeasures to aquaculture pollution in China.

    Science.gov (United States)

    Cao, Ling; Wang, Weimin; Yang, Yi; Yang, Chengtai; Yuan, Zonghui; Xiong, Shanbo; Diana, James

    2007-11-01

    Aquaculture activities are well known to be the major contributor to the increasing level of organic waste and toxic compound in the aquaculture industry. Along with the development of intensive aquaculture in China, concerns are evoked about the possible effects of ever-increasing aquaculture waste both on productivity inside the aquaculture system and on the ambient aquatic ecosystem. Therefore, it is apparent that appropriate waste treatment processes are needed for sustaining aquaculture development. This review aims at identifying the current status of aquaculture and aquaculture waste production in China. China is the world's largest fishery nation in terms of total seafood production volume, a position it has maintained continuously since 1990. Freshwater aquaculture is a major part of the Chinese fishery industry. Marine aquaculture in China consists of both land-based and offshore aquaculture, with the latter mostly operated in shallow seas, mud flats and protected bays. The environmental impacts of aquaculture are also striking. Case studies on pollution hot spots caused by aquaculture have been introduced. The quality and quantity of waste from aquaculture depends mainly on culture system characteristics and the choice of species, but also on feed quality and management. Wastewater without treatment, if continuously discharged into the aquatic environment, could result in remarkable elevation of the total organic matter contents and cause considerable economy lost. Waste treatments can be mainly classified into three categories: physical, chemical and biological methods. The environmental impacts of different aquaculture species are not the same. New waste treatments are introduced as references for the potential development of the waste treatment system in China. The most appropriate waste treatment system for each site should be selected according to the sites' conditions and financial status as well as by weighing the advantages and disadvantages of

  10. 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. © 2012 Blackwell Verlag GmbH.

  11. VIRUS instrument enclosures

    Science.gov (United States)

    Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

    2014-08-01

    The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

  12. PROTEOMICS in aquaculture

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...... 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...... questions and the role of proteomics in their investigation, outlining the advantages, disadvantages and future challenges. A brief description of the proteomics technical approaches will be presented. Special focus will be on the latest trends related to the aquaculture production of fish with defined...

  13. Modeling of humidity-related reliability in enclosures with electronics

    DEFF Research Database (Denmark)

    Hygum, Morten Arnfeldt; Popok, Vladimir

    2015-01-01

    Reliability of electronics that operate outdoor is strongly affected by environmental factors such as temperature and humidity. Fluctuations of these parameters can lead to water condensation inside enclosures. Therefore, modelling of humidity distribution in a container with air and freely exposed...

  14. VLT enclosures: design and construction

    Science.gov (United States)

    Schneermann, Michael W.; Marchiori, Gianpietro; Dimichino, Francesco

    1997-03-01

    The VLT enclosures main functions are to protect the telescopes during operational as well as non-operational phases from any adverse weather conditions and to provide optimal conditions for observation. An adequate design of a ventilation and wind protection system is important for the performance of the enclosures with respect to the minimization of the corresponding seeing effects. The VLT enclosures are equipped with ventilation doors on the azimuth platform level, with louvers on the rotating part and with a windscreen at the observing slit. Extensive qualification tests of the louvers and windscreen mechanical assemblies have been performed during the enclosures development phase. This paper gives an overview over the general layout of the enclosures and the major subsystems, summarizes the main functional specifications and gives the main results and conclusions of the functional performance tests. Presently the first enclosure erection is nearing its completion and pre- commissioning of all systems will commence. The status of the site erection of the enclosures is presented and the planning for the next phases of the erection is presented.

  15. 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......During the last three decades, aquaculture has been the fastest growing animal-food-producing sector in the world, accounting for half of the present seafood supply. However, there is a significant growth disparity among aquaculture-producing countries. The reasons why some countries have achieved...... 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...

  16. Effect of interior geometry on local climate inside an electronic device enclosure

    DEFF Research Database (Denmark)

    Joshy, Salil; Jellesen, Morten Stendahl; Ambat, Rajan

    2017-01-01

    Electronic enclosure design and the internal arrangement of PCBs and components influence microclimate inside the enclosure. This work features a general electronic unit with parallel PCBs. One of the PCB is considered to have heat generating components on it. The humidity and temperature profiles...... geometry of the device and related enclosure design parameters on the humidity and temperature profiles inside the electronic device enclosure....

  17. MROI Array telescopes: the relocatable enclosure domes

    Science.gov (United States)

    Marchiori, G.; Busatta, A.; Payne, I.

    2016-07-01

    The MROI - Magdalena Ridge Interferometer is a project which comprises an array of up to 10 1.4m diameter mirror telescopes arranged in a "Y" configuration. Each of these telescopes will be housed inside a Unit Telescope Enclosure (UTE) which are relocatable onto any of 28 stations. EIE GROUP Srl, Venice - Italy, was awarded the contract for the design, the construction and the erection on site of the MROI by the New Mexico Institute of Mining and Technology. The close-pack array of the MROI - including all 10 telescopes, several of which are at a relative distance of less than 8m center to center from each other - necessitated an original design for the Unit Telescope Enclosure (UTE). This innovative design enclosure incorporates a unique dome/observing aperture system to be able to operate in the harsh environmental conditions encountered at an altitude of 10,460ft (3,188m). The main characteristics of this Relocatable Enclosure Dome are: a Light insulated Steel Structure with a dome made of composites materials (e.g. glass/carbon fibers, sandwich panels etc.), an aperture motorized system for observation, a series of louvers for ventilation, a series of electrical and plants installations and relevant auxiliary equipment. The first Enclosure Dome is now under construction and the completion of the mounting on site id envisaged by the end of 2016. The relocation system utilizes a modified reachstacker (a transporter used to handle freight containers) capable of maneuvering between and around the enclosures, capable of lifting the combined weight of the enclosure with the telescope (30tons), with minimal impacts due to vibrations.

  18. 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.

  19. Process and device for material transfer from a contaminated enclosure into a second enclosure without contamination of this last one

    International Nuclear Information System (INIS)

    Glachet, C.; Ponchet, L.

    1992-01-01

    A shipping container containing a transfer vessel is contacted with the contaminated enclosure. The three coupled doors of the enclosure, of the container and of the vessel are removed together and products are transferred from the enclosure to the vessel, without communication of the atmosphere of the container outside the vessel and of the enclosure are in communication. The 3 doors are closed and the container is removed for transport toward a second enclosure. The three doors of this second enclosure and of the container are opened to introduce in the second enclosure the transfer vessel containing the products

  20. Selecting suitable enclosures for digitally printed materials

    International Nuclear Information System (INIS)

    Burge, D; Rima, L

    2010-01-01

    It cannot be assumed that storage enclosures considered safe for traditionally printed images and documents are suitable for modern, digitally printed materials. In this project, a large variety of digital print types were tested using a modified version of the ISO 18916 Imaging materials-Processed imaging materials-Photographic activity test for enclosure materials standard to assess the risk to digital prints by paper enclosures known to be inert or reactive with traditional photographic prints. The types of enclosures tested included buffered and non-buffered cotton papers, and groundwood paper. In addition, qualitative filter paper that had been wetted and dried with either an acidic or basic solution was also tested to determine the effects of enclosure pH on digitally printed materials. It was determined that, in general, digital prints tended to be less reactive with various enclosure types than traditional prints. Digital prints were most sensitive to paper that contained groundwood. The enclosure reactivity test results were then integrated with previous published work on the tendencies of various enclosure types to abrade, ferrotype, or block to digital prints in order to create a comprehensive set of recommendations for digital print storage enclosures.

  1. Offshore Aquaculture: I Know It When I See It

    Directory of Open Access Journals (Sweden)

    Halley E. Froehlich

    2017-05-01

    Full Text Available Offshore aquaculture is increasingly viewed as a mechanism to meet growing protein demand for seafood, while minimizing adverse consequences on the environment and other uses in the oceans. However, despite growing interest in offshore aquaculture, there appears to be no consensus as to what measures commonly define an offshore site or how effects of offshore aquaculture—relative to more nearshore practices—are assessed. This lack of agreement on what constitutes offshore aquaculture has the potential to convolute communication, create uncertainty in regulatory processes, and impede understanding of the ecological implications of offshore farming. To begin addressing these issues, we reviewed and analyzed biologically-focused primary and gray literature (Ntotal = 70 that categorize and quantify characteristics of offshore aquaculture from around the world. We found that many “offshore” descriptions are relatively close to shore (<3 nm and significantly shallower (minimum depth ≤30 m than may be assumed. We also uncovered an overall lack of consistent reporting of even the most common location-focused metrics (distance from shore, depth, current, a dearth of impact related studies (n = 17, and narrow scope of the studies themselves (i.e., 82% nutrient pollution. Of the finite subset of articles that investigated negative ecological impacts of offshore aquaculture, we found the probability of any measurable impact from an offshore farm appears to significantly decrease with distance from the farm (probability of measurable response at 90 m ± SE = 0.01 ± 0.03. Such general, but informative points of reference could be more robustly quantified with better systematic and standardized reporting of physical farm characteristics and a broader scope of ecological investigation into the effects of marine aquaculture. With offshore aquaculture still in its infancy, consistent metrics are needed for a comparable framework to guide sustainable

  2. 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…

  3. Public Health Perspectives on Aquaculture.

    Science.gov (United States)

    Gormaz, Juan G; Fry, Jillian P; Erazo, Marcia; Love, David C

    2014-01-01

    Nearly half of all seafood consumed globally comes from aquaculture, a method of food production that has expanded rapidly in recent years. Increasing seafood consumption has been proposed as part of a strategy to combat the current non-communicable disease (NCD) pandemic, but public health, environmental, social, and production challenges related to certain types of aquaculture production must be addressed. Resolving these complicated human health and ecologic trade-offs requires systems thinking and collaboration across many fields; the One Health concept is an integrative approach that brings veterinary and human health experts together to combat zoonotic disease. We propose applying and expanding the One Health approach to facilitate collaboration among stakeholders focused on increasing consumption of seafood and expanding aquaculture production, using methods that minimize risks to public health, animal health, and ecology. This expanded application of One Health may also have relevance to other complex systems with similar trade-offs.

  4. 30 CFR 56.12068 - Locking transformer enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Locking transformer enclosures. 56.12068 Section 56.12068 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... § 56.12068 Locking transformer enclosures. Transformer enclosures shall be kept locked against...

  5. 30 CFR 57.12068 - Locking transformer enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Locking transformer enclosures. 57.12068 Section 57.12068 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface Only § 57.12068 Locking transformer enclosures. Transformer enclosures shall be kept...

  6. Acoustic absorption of natural gas compression facility enclosures

    Energy Technology Data Exchange (ETDEWEB)

    Lassen, P.; Wong, G. [Noise Management Ltd., Calgary, AB (Canada)

    2009-07-01

    Noise sources at gas compressor facilities include the enclosure/building housing a gas engine and compressor, the ventilation openings, doors and windows for the enclosure, the engine air intake and exhaust, and a cooler. Accurate predictions of the noise levels inside the enclosure, the breakout noise from open windows and doors and ventilation, as well as the transmission through the walls, is necessary in order to determine cost effective noise mitigation for the facility. In order to accurately predict the sound breakout from these facilities it is necessary to know the acoustic absorption of the interior of these equipment enclosures. Although the acoustic absorption data of the wall systems may be available, the absorption attributable to the non-enclosure surfaces, the equipment and fittings, is not usually known and is difficult to predict. Since piping, instrumentation and mechanical equipment often take on a typical arrangement, shape, volumetric density and material composition, it is useful to know the typical acoustic absorption attributable to these items. In this study, reverberation time (RT) measurements were taken at 2 decommissioned gas compressor facilities in order to determine the absorption characteristics of the enclosure. The RT was measured according to ASTM C423-02a. The overall absorption coefficient of a compressor enclosure with a solid liner was found to be similar to that of steel decking. Fittings within the enclosure did not increase the high frequency absorption of the enclosure. It was concluded that room modes, structural vibrations, and fittings may serve to increase the effective absorption at frequencies below 630 Hz. Because of the small dimensions of the enclosure, low-frequency response of the room affected the reliability of the data below 160Hz. Structural vibration of the enclosure was investigated, and may considerably influence the noise breakout from the enclosure apart from the interior acoustical considerations. 4

  7. Acoustic absorption of natural gas compression facility enclosures

    International Nuclear Information System (INIS)

    Lassen, P.; Wong, G.

    2009-01-01

    Noise sources at gas compressor facilities include the enclosure/building housing a gas engine and compressor, the ventilation openings, doors and windows for the enclosure, the engine air intake and exhaust, and a cooler. Accurate predictions of the noise levels inside the enclosure, the breakout noise from open windows and doors and ventilation, as well as the transmission through the walls, is necessary in order to determine cost effective noise mitigation for the facility. In order to accurately predict the sound breakout from these facilities it is necessary to know the acoustic absorption of the interior of these equipment enclosures. Although the acoustic absorption data of the wall systems may be available, the absorption attributable to the non-enclosure surfaces, the equipment and fittings, is not usually known and is difficult to predict. Since piping, instrumentation and mechanical equipment often take on a typical arrangement, shape, volumetric density and material composition, it is useful to know the typical acoustic absorption attributable to these items. In this study, reverberation time (RT) measurements were taken at 2 decommissioned gas compressor facilities in order to determine the absorption characteristics of the enclosure. The RT was measured according to ASTM C423-02a. The overall absorption coefficient of a compressor enclosure with a solid liner was found to be similar to that of steel decking. Fittings within the enclosure did not increase the high frequency absorption of the enclosure. It was concluded that room modes, structural vibrations, and fittings may serve to increase the effective absorption at frequencies below 630 Hz. Because of the small dimensions of the enclosure, low-frequency response of the room affected the reliability of the data below 160Hz. Structural vibration of the enclosure was investigated, and may considerably influence the noise breakout from the enclosure apart from the interior acoustical considerations. 4

  8. Occupational Health and Safety in Aquaculture: Insights on Brazilian Public Policies.

    Science.gov (United States)

    de Oliveira, Pedro Keller; Cavalli, Richard Souto; Kunert Filho, Hiran Castagnino; Carvalho, Daiane; Benedetti, Nadine; Rotta, Marco Aurélio; Peixoto Ramos, Augusto Sávio; de Brito, Kelly Cristina Tagliari; de Brito, Benito Guimarães; da Rocha, Andréa Ferretto; Stech, Marcia Regina; Cavalli, Lissandra Souto

    2017-01-01

    Aquaculture has many occupational hazards, including those that are physical, chemical, biological, ergonomic, and mechanical. The risks in aquaculture are inherent, as this activity requires particular practices. The objective of the present study was to show the risks associated with the aquaculture sector and present a critical overview on the Brazilian public policies concerning aquaculture occupational health. Methods include online research involved web searches and electronic databases including Pubmed, Google Scholar, Scielo and government databases. We conducted a careful revision of Brazilian labor laws related to occupational health and safety, rural workers, and aquaculture. The results and conclusion support the idea that aquaculture requires specific and well-established industry programs and policies, especially in developing countries. Aquaculture still lacks scientific research, strategies, laws, and public policies to boost the sector with regard to occupational health and safety. The establishment of a safe workplace in aquaculture in developing countries remains a challenge for all involved in employer-employee relationships.

  9. Dependency on aquaculture in northern Vietnam

    DEFF Research Database (Denmark)

    Le Minh, Hanh; Phan, Van Thi; Nghia, Nguyen Huu

    2017-01-01

    a substantial reliance on aquaculture of farmers in the study area with at least half of their income generated by aquaculture. Our analyses highlight that the educational background of farmers explain their engagement in aquaculture better than how long they have worked as aquaculture farmers. Freshwater fish...... the dependence on aquaculture in these two provinces and amongst farmers specializing in shrimp and freshwater fish production, respectively. Further, we tested the ability of different socio-economic variables to explain the observed reliance on aquaculture using an ANCOVA model. The study identifies...

  10. Aquaculture intérieure et adaptation aux changements climatiques ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Risk Management Practices. Briefs. Aquaculture and Climate. Journal articles. River-based cage aquaculture of tilapia in Northern Thailand : sustainability of rearing and business practices. Journal articles. Learning about climate-related risks: decisions of Northern Thailand fish farmers in a role-playing simulation game ...

  11. Proteomics and its applications to aquaculture in China: infection, immunity, and interaction of aquaculture hosts with pathogens.

    Science.gov (United States)

    Peng, Xuan-Xian

    2013-01-01

    China is the largest fishery producer worldwide in term of its aquaculture output, and plays leading and decisive roles in international aquaculture development. To improve aquaculture output further and promote aquaculture business development, infectious diseases and immunity of fishes and other aquaculture species must be studied. In this regard, aquaculture proteomics has been widely carried out in China to get a better understanding of aquaculture host immunity and microbial pathogenesis as well as host-pathogen interactions, and to identify novel disease targets and vaccine candidates for therapeutic interventions. These proteomics studies include development of novel methods, assays, and advanced concepts in order to characterize proteomics mechanisms of host innate immune defense and microbial pathogenesis. This review article summarizes some recently published technical approaches and their applications to aquaculture proteomics with an emphasis on the responses of aquaculture animals to bacteria, viruses, and other aqua-environmental stresses, and development of broadly cross-protective vaccine candidates. The reviewed articles are those that have been published in international peer reviewed journals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. 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

  13. Feeding aquaculture in an era of finite resources

    Science.gov (United States)

    Naylor, Rosamond L.; Hardy, Ronald W.; Bureau, Dominique P.; Chiu, Alice; Elliott, Matthew; Farrell, Anthony P.; Forster, Ian; Gatlin, Delbert M.; Goldburg, Rebecca J.; Hua, Katheline; Nichols, Peter D.

    2009-01-01

    Aquaculture's pressure on forage fisheries remains hotly contested. This article reviews trends in fishmeal and fish oil use in industrial aquafeeds, showing reduced inclusion rates but greater total use associated with increased aquaculture production and demand for fish high in long-chain omega-3 oils. The ratio of wild fisheries inputs to farmed fish output has fallen to 0.63 for the aquaculture sector as a whole but remains as high as 5.0 for Atlantic salmon. Various plant- and animal-based alternatives are now used or available for industrial aquafeeds, depending on relative prices and consumer acceptance, and the outlook for single-cell organisms to replace fish oil is promising. With appropriate economic and regulatory incentives, the transition toward alternative feedstuffs could accelerate, paving the way for a consensus that aquaculture is aiding the ocean, not depleting it. PMID:19805247

  14. Aquaculture Simulator

    OpenAIRE

    Bøe, Trond Anders

    2015-01-01

    Salmon fish farming has evolved to become a multi-billion dollar industry for Norway, with a significant growth in the last 10 years. With the introduction of modern and advanced technical equipment and higher environmental demands, follows a need for further training of experienced fish farmers and aquaculture students. Spreading knowledge about aquaculture and get people interested in the industry is important in order to secure future growth. This project will continue the development o...

  15. Mechanisms of quorum sensing and strategies for quorum sensing disruption in aquaculture pathogens.

    Science.gov (United States)

    Zhao, J; Chen, M; Quan, C S; Fan, S D

    2015-09-01

    In many countries, infectious diseases are a considerable threat to aquaculture. The pathogenicity of micro-organisms that infect aquaculture systems is closely related to the release of virulence factors and the formation of biofilms, both of which are regulated by quorum sensing (QS). Thus, QS disruption is a potential strategy for preventing disease in aquaculture systems. QS inhibitors (QSIs) not only inhibit the expression of virulence-associated genes but also attenuate the virulence of aquaculture pathogens. In this review, we discuss QS systems in important aquaculture pathogens and focus on the relationship between QS mechanisms and bacterial virulence in aquaculture. We further elucidate QS disruption strategies for targeting aquaculture pathogens. Four main types of QSIs that target aquaculture pathogens are discussed based on their mechanisms of action. © 2014 John Wiley & Sons Ltd.

  16. Semi-empirical prediction of moisture build-up in an electronic enclosure using analysis of variance (ANOVA)

    DEFF Research Database (Denmark)

    Shojaee Nasirabadi, Parizad; Conseil, Helene; Mohanty, Sankhya

    2016-01-01

    Electronic systems are exposed to harsh environmental conditions such as high humidity in many applications. Moisture transfer into electronic enclosures and condensation can cause several problems as material degradation and corrosion. Therefore, it is important to control the moisture content...... and the relative humidity inside electronic enclosures. In this work, moisture transfer into a typical polycarbonate electronic enclosure with a cylindrical shape opening is studied. The effects of four influential parameters namely, initial relative humidity inside the enclosure, radius and length of the opening...... and temperature are studied. A set of experiments are done based on a fractional factorial design in order to estimate the time constant for moisture transfer into the enclosure by fitting the experimental data to an analytical quasi-steady-state model. According to the statistical analysis, temperature...

  17. Nuclear power plant with a safety enclosure

    International Nuclear Information System (INIS)

    Keller, W.; Krueger, J.; Ropers, J.; Schabert, H.P.

    1976-01-01

    A nuclear power plant has a safety enclosure for a nuclear reactor. A fuel element storage basin is also located in this safety enclosure and a fuel element lock extends through the enclosure, with a cross-sectional size proportioned for the endwise passage of fuel elements, the lock including internal and external valves so that a fuel element may be locked endwise safely through the lock. The lock, including its valves, being of small size, does not materially affect the pressure resistance of the safety enclosure, and it is more easily operated than a lock large enough to pass people and fuel element transport vessels

  18. 50 CFR 14.142 - Primary enclosures.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Primary enclosures. 14.142 Section 14.142 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR TAKING... outside the enclosure. Specifications for Sloths, Bats, and Flying Lemurs (Cynocephalidae) ...

  19. 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.

  20. Public Perceptions of Aquaculture: Evaluating Spatiotemporal Patterns of Sentiment around the World.

    Directory of Open Access Journals (Sweden)

    Halley E Froehlich

    Full Text Available Aquaculture is developing rapidly at a global scale and sustainable practices are an essential part of meeting the protein requirements of the ballooning human population. Locating aquaculture offshore is one strategy that may help address some issues related to nearshore development. However, offshore production is nascent and distinctions between the types of aquatic farming may not be fully understood by the public-important for collaboration, research, and development. Here we evaluate and report, to our knowledge, the first multinational quantification of the relative sentiments and opinions of the public around distinct forms of aquaculture. Using thousands of newspaper headlines (Ntotal = 1,596 from developed (no. countries = 26 and developing (42 nations, ranging over periods of 1984 to 2015, we found an expanding positive trend of general 'aquaculture' coverage, while 'marine' and 'offshore' appeared more negative. Overall, developing regions published proportionally more positive than negative headlines than developed countries. As case studies, government collected public comments (Ntotal = 1,585 from the United States of America (USA and New Zealand mirrored the media sentiments; offshore perception being particularly negative in the USA. We also found public sentiment may be influenced by local environmental disasters not directly related to aquaculture (e.g., oil spills. Both countries voiced concern over environmental impacts, but the concerns tended to be more generalized, rather than targeted issues. Two factors that could be inhibiting informed discussion and decisions about offshore aquaculture are lack of applicable knowledge and actual local development issues. Better communication and investigation of the real versus perceived impacts of aquaculture could aid in clarifying the debate about aquaculture, and help support future sustainable growth.

  1. PROTEOMICS in aquaculture: applications and trends.

    Science.gov (United States)

    Rodrigues, Pedro M; Silva, Tomé S; Dias, Jorge; Jessen, Flemming

    2012-07-19

    Over the last forty years global aquaculture presented a growth rate of 6.9% per annum with an amazing production of 52.5 million 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 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 of proteomics in seafood biology research. Proteomics, as a powerful comparative tool, has therefore been increasingly used over the last decade to address different questions in aquaculture, regarding welfare, nutrition, health, quality, and safety. In this paper we will give an overview of these biological questions and the role of proteomics in their investigation, outlining the advantages, disadvantages and future challenges. A brief description of the proteomics technical approaches will be presented. Special focus will be on the latest trends related to the aquaculture production of fish with defined nutritional, health or quality properties for functional foods and the integration of proteomics techniques in addressing this challenging issue. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Epigenetic considerations in aquaculture

    Directory of Open Access Journals (Sweden)

    Mackenzie R. Gavery

    2017-12-01

    Full Text Available Epigenetics has attracted considerable attention with respect to its potential value in many areas of agricultural production, particularly under conditions where the environment can be manipulated or natural variation exists. Here we introduce key concepts and definitions of epigenetic mechanisms, including DNA methylation, histone modifications and non-coding RNA, review the current understanding of epigenetics in both fish and shellfish, and propose key areas of aquaculture where epigenetics could be applied. The first key area is environmental manipulation, where the intention is to induce an ‘epigenetic memory’ either within or between generations to produce a desired phenotype. The second key area is epigenetic selection, which, alone or combined with genetic selection, may increase the reliability of producing animals with desired phenotypes. Based on aspects of life history and husbandry practices in aquaculture species, the application of epigenetic knowledge could significantly affect the productivity and sustainability of aquaculture practices. Conversely, clarifying the role of epigenetic mechanisms in aquaculture species may upend traditional assumptions about selection practices. Ultimately, there are still many unanswered questions regarding how epigenetic mechanisms might be leveraged in aquaculture.

  3. Offshore Aquaculture Development in Ecuador

    Directory of Open Access Journals (Sweden)

    Julio López Alvarado

    2016-03-01

    Full Text Available Ecuador has a long tradition in aquaculture, mainly related to the cultivation of shrimp and tilapia in earthen ponds. Land-based production methods have a large environmental, economic and social impact due to the extensive use of land and its effects on the ecosystems. In order to increase the production of fish without further land use and with a lower environmental impact, a good alternative is the culture of fish in floating cages, adopting technologies used successfully in many other countries. This article analyses the current situation of offshore aquaculture (the production of fish and other aquatic organisms in the open sea in Ecuador, and the prospects for the future of this sector in the country.

  4. The 3.5-Meter Telescope Enclosure

    Science.gov (United States)

    1994-04-01

    and acoustic vibrations, and the enclosure cannot be stopped quickly in an emergency. Also, the work of Zago indicates that open-air operation of the...enclosure. This capability is useful during operational testing and maintenance of the telescope. ’ Zago , L., "Design and Performance of Large

  5. Humidity evolution (breathing effect) in enclosures with electronics

    DEFF Research Database (Denmark)

    Hygum, Morten Arnfeldt; Popok, Vladimir

    2015-01-01

    Packaging and enclosures used for protecting power electronics operating outdoors are designed to withstand the local climatic and environmental changes. Hermetic enclosures are expensive and therefore other solutions for protecting the electronics from a harsh environment are required. One...... of the dangerous parameters is high humidity of air. Moisture can inevitable reach the electronics either due to diffusion through the wall of an enclosure or small holes, which are designed for electrical or other connections. A driving force for humid air movement is the temperature difference between...... the operating electronics and the surrounding environment. This temperature, thus, gives rise to a natural convection, which we also refer to as breathing. Robust and intelligent enclosure designs must account for this breathing as it can significantly change the humidity distribution in the enclosure...

  6. A sealed enclosure of the glove box type

    International Nuclear Information System (INIS)

    Moreels, Pierre.

    1974-01-01

    The invention relates to a sealed enclosure of the glove-box type. According to the invention, the box-frame comprises: angle-bars having a right-angled cross-section, sealing joints, tightening bars and fastening means [fr

  7. Microbial populations causing off-flavour in recirculated aquaculture systems

    DEFF Research Database (Denmark)

    Lukassen, Mie Bech; Schramm, Edward; Nielsen, Jeppe Lund

    the distribution of geoA in more than 50 European and Brazilian aquaculture systems has allowed us to identify the diversity among geosmin-producing bacteria. The different populations of geosmin-producers were evaluated relative to plant design, environmental and operational parameters in full-scale aquaculture...... systems using multivariate statistics. The influencing parameters identified were subsequently validated by testing their gene expressions in well-controlled pilot scale aquaculture systems. The results show that the geoA gene is a relative well-conserved gene with limited horizontal gene transfer events...... phase. Furthermore, the gene expressions of the individual groups show positive correlations to the organic loading and presence of oxygen. The current study reveals the presence of important populations involved in geosmin production and which parameters are of importance for their presence...

  8. Chinese aquaculture in light of green growth

    OpenAIRE

    Leilei Zou; Shuolin Huang

    2015-01-01

    Over China’s long history of aquaculture development, great achievements have been made by enhancing aquaculture as the major contributor to aquatic products supply, while lessons have also been learnt that aquaculture has been developing at the cost of environment. Priority is now given to the aquaculture development in the light of green growth, which attaches importance to both environment protection and high productivity. To sustain Chinese aquaculture in a green-growth manner, polices ch...

  9. Limiting enclosures - Filtering fittings for air or gas

    International Nuclear Information System (INIS)

    1981-05-01

    The aim of this experimental standard is the determination of the general characteristics of air or gas filtration equipment for limiting enclosures in application of the standard M 62-202. Application are made on enclosures or enclosure lines used for works on radioactive materials, toxic or dangerous chemicals, materials sensitive to atmospheric components or requiring a steril atmosphere [fr

  10. Antimicrobial resistance and antimicrobial resistance genes in marine bacteria from salmon aquaculture and non-aquaculture sites.

    Science.gov (United States)

    Shah, Syed Q A; Cabello, Felipe C; L'abée-Lund, Trine M; Tomova, Alexandra; Godfrey, Henry P; Buschmann, Alejandro H; Sørum, Henning

    2014-05-01

    Antimicrobial resistance (AR) detected by disc diffusion and antimicrobial resistance genes detected by DNA hybridization and polymerase chain reaction with amplicon sequencing were studied in 124 marine bacterial isolates from a Chilean salmon aquaculture site and 76 from a site without aquaculture 8 km distant. Resistance to one or more antimicrobials was present in 81% of the isolates regardless of site. Resistance to tetracycline was most commonly encoded by tetA and tetG; to trimethoprim, by dfrA1, dfrA5 and dfrA12; to sulfamethizole, by sul1 and sul2; to amoxicillin, by blaTEM ; and to streptomycin, by strA-strB. Integron integrase intl1 was detected in 14 sul1-positive isolates, associated with aad9 gene cassettes in two from the aquaculture site. intl2 Integrase was only detected in three dfrA1-positive isolates from the aquaculture site and was not associated with gene cassettes in any. Of nine isolates tested for conjugation, two from the aquaculture site transferred AR determinants to Escherichia coli. High levels of AR in marine sediments from aquaculture and non-aquaculture sites suggest that dispersion of the large amounts of antimicrobials used in Chilean salmon aquaculture has created selective pressure in areas of the marine environment far removed from the initial site of use of these agents. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. Preconceptual design for the electrostatic enclosure

    International Nuclear Information System (INIS)

    Meyer, L.C.

    1992-09-01

    This report presents a preconceptual design (design criteria and assumptions) for electrostatic enclosures to be used during buried transuranic waste recovery operations. These electrostatic enclosures (along with the application of dust control products) will provide an in-depth contamination control strategy. As part of this preconceptual design, options for electrostatic curtain design are given including both hardwall and fabric enclosures. Ventilation systems, doors, air locks, electrostatic curtains, and supporting systems also are discussed. In addition to the conceptual design, engineering scale tests are proposed to be run at the Test Reactor Area. The planned engineering scale tests will give final material specifications for full-scale retrieval demonstrations

  12. Fire Research Enclosure

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Simulates submarine fires, enclosed aircraft fires, and fires in enclosures at shore facilities .DESCRIPTION: FIRE I is a pressurizable, 324 cu m(11,400 cu...

  13. Hydrogen peroxide decomposition kinetics in aquaculture water

    DEFF Research Database (Denmark)

    Arvin, Erik; Pedersen, Lars-Flemming

    2015-01-01

    during the HP decomposition. The model assumes that the enzyme decay is controlled by an inactivation stoichiometry related to the HP decomposition. In order to make the model easily applicable, it is furthermore assumed that the COD is a proxy of the active biomass concentration of the water and thereby......Hydrogen peroxide (HP) is used in aquaculture systems where preventive or curative water treatments occasionally are required. Use of chemical agents can be challenging in recirculating aquaculture systems (RAS) due to extended water retention time and because the agents must not damage the fish...... reared or the nitrifying bacteria in the biofilters at concentrations required to eliminating pathogens. This calls for quantitative insight into the fate of the disinfectant residuals during water treatment. This paper presents a kinetic model that describes the HP decomposition in aquaculture water...

  14. Public attitudes towards marine aquaculture: A comparative analysis of Germany and Israel

    International Nuclear Information System (INIS)

    Freeman, Shirra; Vigoda-Gadot, Eran; Sterr, Horst; Schultz, Michael; Korchenkov, Irina; Krost, Peter; Angel, Dror

    2012-01-01

    We report on bi-national (Germany–Israel) research on relationships between public attitudes, behaviours and preferences related to marine aquaculture. Aquaculture's world-wide market share accounts for over half of all aquatic products. In many places, the sector's explosive growth has outstripped scientific knowledge and governance provisions. Small producers such as Israel and Germany seeking to expand domestic production must address environmental challenges posed by fish farming, stakeholder competition in crowded coastal zones and public/consumer receptiveness. Based on survey data obtained from both the countries, correlation analysis (Pearson's r-statistic) was used to test four hypotheses. Of these, one (positive relationship between coastal tourism and aquaculture attitudes) was supported in both countries. The hypothesis of positive relationships between lifestyle (environment/health) behaviours and aquaculture attitudes was supported only in Germany and the hypothesis of negative relationships between concern for the environment and aquaculture attitudes was supported only in Israel. These results are significant for policy, business, NGO and other stakeholders. Moreover, they point to the importance of this type of comparative research in improving our understanding of local factors influencing attitude-formation and inter-relationships. First, the tourism–aquaculture relationship found indicates potential synergies between two sectors reliant on the coastal zone that should be taken into account by planning authorities. The divergent environment–aquaculture results were especially interesting since in both countries, the primary concern regarding aquaculture expansion was environmental impacts. Closer inspection of the survey results revealed that this relationship may have been influenced by the orientation of environmental concerns in each population. Germans focus on depletion of wildstocks and Israelis on cage effluent and marine pollution

  15. 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 ...

  16. Isotopes in aquaculture research

    International Nuclear Information System (INIS)

    Ayyappan, S.; Dash, B.; Ghosh, A.S.

    1996-01-01

    The applications of isotopes in aquaculture research include areas like aquatic production process, nutrient cycles and food chain dynamics, fish nutrition, fish physiology, genetics and immunology. The radioisotopes commonly used are beta emitters. The use of different radioisotopes in aquaculture research are presented. 2 tabs

  17. Cumulative effects, creeping enclosure, and the marine commons of New Jersey

    Directory of Open Access Journals (Sweden)

    Grant Murray

    2010-02-01

    Full Text Available In response to declining fish stocks and increased societal concern, the marine ‘commons’ of New Jersey is no longer freely available to commercial and recreational fisheries. We discuss the concept of ‘creeping’ enclosure in relation to New Jersey’s marine fisheries and suggest that reduced access can be a cumulative process and function of multiple events and processes and need not be the result of a single regulatory moment. We begin with a short review of the ‘expected’ effects of enclosure, including loss of flexibility, erosion of community, proletarianization of fishermen, and corporatization of the fishery. We then present some findings of our research and discuss how the signs of enclosure are visible in fisheries that do not feature explicitly privatized property or access rights. We rely on an oral history approach and the rich detail that emerges from attention to the lived experiences of fish harvesters to provide a framework for understanding the range of cumulative effects that have resulted from this process of creeping enclosure. We conclude with a discussion of how the gradual process of enclosure has affected the flows of information between the bio-physical environment and fish harvesters, managers and scientists by reducing both participation in fisheries and the accumulation of knowledge itself.

  18. Alien species in aquaculture and biodiversity: a paradox in food production.

    Science.gov (United States)

    De Silva, Sena S; Nguyen, Thuy T T; Turchini, Giovanni M; Amarasinghe, Upali S; Abery, Nigel W

    2009-02-01

    Aquaculture is seen as an alternative to meeting the widening gap in global rising demand and decreasing supply for aquatic food products. Asia, the epicenter of the global aquaculture industry, accounts for over 90% of the global aquaculture production quantity and about 80% of the value. Asian aquaculture, as with global aquaculture, is dependent to a significant extent on alien species, as is the case for all the major food crops and husbanded terrestrial animals. However, voluntary and or accidental introduction of exotic aquatic species (alien species) is known to negatively impact local biodiversity. In this relatively young food production industry, mitigating the dependence on alien species, and thereby minimizing potential negative impacts on biodiversity, is an imperative for a sustainable future. In this context an attempt is made in this synthesis to understand such phenomena, especially with reference to Asian inland finfish, the mainstay of global aquaculture production. It is pointed out that there is potential for aquaculture, which is becoming an increasingly important food production process, not to follow the past path of terrestrial food crops and husbanded animals in regard to their negative influences on biodiversity.

  19. 40 CFR 86.117-96 - Evaporative emission enclosure calibrations.

    Science.gov (United States)

    2010-07-01

    ... periodic determination of enclosure background emissions. Prior to its introduction into service, annually... procedure: (1) Carefully measure the internal length, width and height of the enclosure, accounting for... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Evaporative emission enclosure...

  20. Shielded enclosure for handling radioactive material

    International Nuclear Information System (INIS)

    Laurent, H.; Courouble, J.M.

    1959-01-01

    Two enclosures linked by an air-lock are described: they are designed for the safe handling of 5 curies 0.3 to 0.5 MeV γ emitters, and each is composed of a semi-tight case, ventilated, clad in 80 mm steel plate, and suited for a wide variety of physics and chemistry operations. The equipment required for any given operation can be installed in the shortest possible time, access to the enclosure being via a removable front. Visual control is assured through a lead-glass screen. Each enclosure is fitted with a master-slave manipulator, Argon model 7, and plugs and air-locks are provided for the introduction of liquids and solids. (author) [fr

  1. Track plate enclosures: Box designs affecting attractiveness to riparian mammals

    Science.gov (United States)

    Loukmas, J.J.; Mayack, D.T.; Richmond, M.E.

    2003-01-01

    We examined the efficacy of four track plate enclosure designs for monitoring the abundance of small and medium-sized mammals along 10 streams in New York State. Box size and clarity of view through the box were evaluated as factors affecting visitation. We checked track plate stations weekly from September 1999 to March 2000. Eleven mammalian species or species groups visited the track plate stations. Raccoons (Procyon lotor) (P = 0.020) and feral cats (Felis catus) (P = 0.008) visited large enclosures significantly more than small enclosures. Feral cats visited clear-view enclosures significantly more than obstructed-view enclosures (P = 0.025). Enclosure size and view did not significantly affect visitation by other species; however, a large box with a clear view was the most effective design.

  2. 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....

  3. Effects of nanoparticles in species of aquaculture interest.

    Science.gov (United States)

    Khosravi-Katuli, Kheyrollah; Prato, Ermelinda; Lofrano, Giusy; Guida, Marco; Vale, Gonçalo; Libralato, Giovanni

    2017-07-01

    Recently, it was observed that there is an increasing application of nanoparticles (NPs) in aquaculture. Manufacturers are trying to use nano-based tools to remove the barriers about waterborne food, growth, reproduction, and culturing of species, their health, and water treatment in order to increase aquaculture production rates, being the safe-by-design approach still unapplied. We reviewed the applications of NPs in aquaculture evidencing that the way NPs are applied can be very different: some are direclty added to feed, other to water media or in aquaculture facilities. Traditional toxicity data cannot be easily used to infer on aquaculture mainly considering short-term exposure scenarios, underestimating the potential exposure of aquacultured species. The main outputs are (i) biological models are not recurrent, and in the case, testing protocols are frequently different; (ii) most data derived from toxicity studies are not specifically designed on aquaculture needs, thus contact time, exposure concentrations, and other ancillary conditions do not meet the required standard for aquaculture; (iii) short-term exposure periods are investigated mainly on species of indirect aquaculture interest, while shrimp and fish as final consumers in aquaculture plants are underinvestigated (scarce or unknown data on trophic chain transfer of NPs): little information is available about the amount of NPs accumulated within marketed organisms; (iv) how NPs present in the packaging of aquacultured products can affect their quality remained substantially unexplored. NPs in aquaculture are a challenging topic that must be developed in the near future to assure human health and environmental safety. Graphical abstract ᅟ.

  4. Biotechnological Innovations in Aquaculture

    Directory of Open Access Journals (Sweden)

    Mangesh M. Bhosale

    2016-04-01

    Full Text Available Aquaculture is gaining commendable importance to meet the required protein source for ever increasing human population. The aquaculture industry is currently facing problems on developing economically viable production systems by reducing the impact on environment. Sustainable and enhanced fish production from aquaculture may be better achieved through application of recent biotechnological innovations. Utilisation of transgenic technology has led to production of fishes with faster growth rate with disease resistance. The full advantage of this technology could not be achieved due to concern of acceptance for Genetically Modified Organisms (GMOs. The biotechnological intervention in developing plant based feed ingredient in place of fish meal which contain high phosphorus is of prime area of attention for fish feed industry. The replacement of fish meal will also reduce fish feed cost to a greater extent. Year round fish seed production of carps through various biotechnological interventions is also need of the hour. This paper discusses technical, environmental and managerial considerations regarding the use of these biotechnological tools in aquaculture along with the advantages of research application and its commercialization.

  5. Enclosure enhancement of flight performance

    KAUST Repository

    Ghommem, Mehdi; Garcia, Daniel; Calo, Victor M.

    2014-01-01

    We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

  6. Enclosure enhancement of flight performance

    KAUST Repository

    Ghommem, Mehdi

    2014-08-19

    We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

  7. Rose Canyon Sustainable Aquaculture Project, San Diego, CA

    Science.gov (United States)

    Documents related to EPA's preparation of an Environmental Assessment (EA) to analyze the potential impacts related to the issuance of a National Pollutant Discharge Elimination System (NPDES) permit for the Rose Canyon Sustainable Aquaculture Project.

  8. Attitudinal Factors and Personal Characteristics Influence Support for Shellfish Aquaculture in Rhode Island (US) Coastal Waters.

    Science.gov (United States)

    Dalton, Tracey M; Jin, Di

    2018-05-01

    This study explores public interests associated with shellfish aquaculture development in coastal waters of Rhode Island (US). Specifically, we examine (1) the levels of public support for (or opposition to) shellfish aquaculture development and (2) factors driving the levels of support, using survey data and ordinal logistic regressions. Results of the analysis identify several key attitudinal factors affecting individual's support for shellfish aquaculture in Rhode Island (RI). The level of support is positively associated with attitudes related to shellfish aquaculture's benefits to the local economy and its role as a nutritional food option, and negatively influenced by attitudes related to aquaculture farms' effects on aesthetic quality and their interference with other uses. Findings highlight that support for (or opposition to) aquaculture in RI is driven more by attitudes associated with social impacts than by those associated with environmental impacts. The level of support is also affected by personal characteristics related to an individual's participation in recreational activities. For instance, bicycle riders tend to be supportive of shellfish aquaculture while respondents who participate in sailing and birding are less supportive. By identifying the broader public's interests in shellfish aquaculture, findings from this study and others like it can be used to address public concerns, incorporate public perceptions and attitudes into permitting decisions, and develop outreach targeted at specific stakeholder groups.

  9. Enclosure enhancement of flight performance

    Directory of Open Access Journals (Sweden)

    Mehdi Ghommem

    2014-01-01

    Full Text Available We use a potential flow solver to investigate the aerodynamic aspects of flapping flights in enclosed spaces. The enclosure effects are simulated by the method of images. Our study complements previous aerodynamic analyses which considered only the near-ground flight. The present results show that flying in the proximity of an enclosure affects the aerodynamic performance of flapping wings in terms of lift and thrust generation and power consumption. It leads to higher flight efficiency and more than 5% increase of the generation of lift and thrust.

  10. 30 CFR 75.819 - Motor-starter enclosures; barriers and interlocks.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Motor-starter enclosures; barriers and...-Voltage Distribution High-Voltage Longwalls § 75.819 Motor-starter enclosures; barriers and interlocks. Compartment separation and cover interlock switches for motor-starter enclosures must be maintained in...

  11. Meeting the Needs for More Fish Through Aquaculture

    Science.gov (United States)

    Giap, D. H.; Lam, T. J.

    2015-10-01

    Fish is one of the major sources of animal protein. Due to rising world populations, increasing income and urbanization, demand for fish has been increasing. In order to meet the need for more fish, aquaculture has become increasingly important as wild populations and production from capture fisheries have declined due to overfishing and poor management. In recent years, production from aquaculture has increased rapidly to address the shortfalls in capture fisheries, especially in Asia where aquaculture production accounts for about 90% of world aquaculture production by volume. This paper reviews the status of the world’s fish production, provides an update on Asian aquaculture, and highlights developments that are contributing to sustainable fish production, particularly integrated multi-trophic aquaculture and aquaponics.

  12. Captive chimpanzee (Pan troglodytes) behavior as a function of space per animal and enclosure type.

    Science.gov (United States)

    Neal Webb, Sarah J; Hau, Jann; Schapiro, Steven J

    2018-03-01

    Space per animal, or animal density, and enclosure type are important elements of functionally appropriate captive environments (FACEs) for chimpanzees. The National Institutes of Health (NIH) recommends that captive chimpanzees be maintained in areas of >250 ft 2 /animal. Several studies have investigated chimpanzee behavior in relation to space per animal, but only two studies have examined these variables while attempting to hold environmental complexity constant. Both have found few, if any, significant differences in behavior associated with increased space per animal. The NIH does not provide recommendations pertaining to enclosure type. Although Primadomes™ and corrals are considered acceptable FACE housing, no studies have investigated chimpanzee behavior in relation to these two common types of enclosures. We examined the NIH space per animal recommendation, and the effects of enclosure type, while maintaining similar levels of environmental complexity. We used focal animal observations to record the behavior of 22 chimpanzees in three social groups following within-facility housing transfers. Chimpanzees that were moved from an area with space below the NIH recommendation to the same type of enclosure with space above the recommendation (dome to double dome) exhibited significantly more locomotion and behavioral diversity post-transfer. Chimpanzees that were moved from an area with space below the recommendation to a different type of enclosure with space above the recommendation (dome to corral) exhibited significant increases in foraging and behavioral diversity, and a decrease in rough scratching. Lastly, chimpanzees that were moved from an area above the recommendation to a different enclosure type with space equal to the recommendation (corral to double dome) exhibited an increase in behavioral diversity. These results add to the body of literature that addresses the concept of specific minimum space requirements per chimpanzee, and highlight the

  13. Status analysis of Chinese standards on enclosure equipment and proposed countermeasures

    International Nuclear Information System (INIS)

    Wu Luping

    1998-12-01

    Enclosure equipment, such as glove box, tong box etc., is an important kind of equipment for nuclear industry and nuclear scientific research. The status of the establishment and implementation of Chinese standards on enclosure equipment is briefly described. Some problems and deficiency existing in these standards are pointed out. The ISO standard projects on containment enclosures as well as their present progress situations are introduced. The measure for updating Chinese standards on enclosure equipment in accordance with the principle of adopting international standards are recommended. Some issues which should be taken into account in adopting ISO standards on containment enclosures are also discussed

  14. Aquaculture. Second Edition. Teacher Edition.

    Science.gov (United States)

    Walker, Susan S.; Crummett, Dan

    This teacher and student guide for aquaculture contains 15 units of instruction that cover the following topics: (1) introduction to aquaculture; (2) the aquatic environment; (3) fundamental fish biology; (4) marketing; (5) site selection; (6) facility design and layout; (7) water quality management; (8) fish health management; (9) commercial…

  15. THE DEVELOPMENT OF THE ORGANIC AQUACULTURE. CASE STUDY: ROMANIA

    Directory of Open Access Journals (Sweden)

    Silvius STANCIU

    2015-12-01

    Full Text Available Aquaculture contribute ever more to the production of aquatic food worldwide, even if the sustainable limits for majority of wild fish stocks, are now almost reached or even exceeded. In the EU, aquaculture is an important economic activity in many coastal and continental regions. Aquaculture plays an important role in terms of access to food resources and it is necessary to use its potential to contribute to sustainable development, food security, economic growth and employment. In this regard, starting from EU aquaculture objectives, the paper intend to make an analysis of the national situation of aquaculture and its current potential. The paper presented the progress of Romanian investments in aquaculture, identifying needs and opportunities for the Romanian aquaculture development. Taking into consideration the natural resources available and the growth of global request of organic product, the development of ecologic aquaculture might represent o niche market for local producers.

  16. 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

  17. Interaction Between Flow Elements in Large Enclosures

    DEFF Research Database (Denmark)

    Heiselberg, Per

    and if this influences the overall air flow pattern in the enclosure. The main emphasis has been put on the pathways of chilled free air jets and whether the convective flows from both distributed and concentrated heat sources affect the pathway of the jet and the air flow pattern in the enclosure as a function......In this paper experiments in a scale model are used as a first attempt to investigate how different flow elements such as supply air jets, thermal plumes and free convection flows interact with each other in a large enclosure, if the path of each individual flow element changes...... of the location of the heat source and as a function of the heat supplied by the source....

  18. Enclosure for handling high activity materials

    International Nuclear Information System (INIS)

    Jimeno de Osso, F.

    1977-01-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With this purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. In this report a description is given of those aspects that may be of interest to people working in this field. (Author)

  19. Enclosure for handling high activity materials

    Energy Technology Data Exchange (ETDEWEB)

    Jimeno de Osso, F

    1977-07-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With this purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. In this report a description is given of those aspects that may be of interest to people working in this field. (Author)

  20. Natural convection in asymmetric triangular enclosures heated from below

    Science.gov (United States)

    Kamiyo, O. M.; Angeli, D.; Barozzi, G. S.; Collins, M. W.

    2014-11-01

    Triangular enclosures are typical configurations of attic spaces found in residential as well as industrial pitched-roof buildings. Natural convection in triangular rooftops has received considerable attention over the years, mainly on right-angled and isosceles enclosures. In this paper, a finite volume CFD package is employed to study the laminar air flow and temperature distribution in asymmetric rooftop-shaped triangular enclosures when heated isothermally from the base wall, for aspect ratios (AR) 0.2 <= AR <= 1.0, and Rayleigh number (Ra) values 8 × 105 <= Ra <= 5 × 107. The effects of Rayleigh number and pitch angle on the flow structure and temperature distributions within the enclosure are analysed. Results indicate that, at low pitch angle, the heat transfer between the cold inclined and the hot base walls is very high, resulting in a multi-cellular flow structure. As the pitch angle increases, however, the number of cells reduces, and the total heat transfer rate progressively reduces, even if the Rayleigh number, being based on the enclosure height, rapidly increases. Physical reasons for the above effect are inspected.

  1. The influence of enclosure design on diurnal activity and stereotypic behaviour in captive Malayan Sun bears (Helarctos malayanus).

    Science.gov (United States)

    Tan, H M; Ong, S M; Langat, G; Bahaman, A R; Sharma, R S K; Sumita, S

    2013-04-01

    The effect of enclosure design on diurnal activity and stereotypic behaviour was assessed in 17 adult Malayan Sun bears (Helarctos malayanus), kept either in barren indoor enclosures or relatively enriched outdoor enclosures. Locomotion was the most frequent activity observed in the indoor bears, followed by resting. In contrast, conspecifics housed outdoors spent most of the time resting. Eleven forms of stereotypic behaviours were recorded in the bears, with pacing being the most common. The frequency and repertoire of stereotypies were significantly higher in the indoor bears irrespective of enclosure size. Novel forms of locomotor (forward-reverse pacing) and oral (allo-sucking) stereotypies were recorded. Oral stereotypies were predominant in the bears housed indoors, while patrolling was confined to the outdoor bears. Enclosure complexity significantly influences activity budget and occurrence of stereotypic behaviours, highlighting the importance of appropriate enclosure design and enrichment for the welfare of captive bears. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. The use of Probiotics in Aquaculture

    African Journals Online (AJOL)

    JOSEPH

    Addressing health questions with both pro-active and reactive programmes has thus .... Rationale for selecting and developing probiotics in aquaculture: The ... of probiotics in aquaculture could be regarded as a kind of insurance since it may ...

  3. 46 CFR 169.677 - Equipment protection and enclosure.

    Science.gov (United States)

    2010-10-01

    ... Vessels of Less Than 100 Gross Tons § 169.677 Equipment protection and enclosure. (a) Except as provided... 46 Shipping 7 2010-10-01 2010-10-01 false Equipment protection and enclosure. 169.677 Section 169.677 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL...

  4. Application of Machine Learning Techniques in Aquaculture

    OpenAIRE

    Rahman, Akhlaqur; Tasnim, Sumaira

    2014-01-01

    In this paper we present applications of different machine learning algorithms in aquaculture. Machine learning algorithms learn models from historical data. In aquaculture historical data are obtained from farm practices, yields, and environmental data sources. Associations between these different variables can be obtained by applying machine learning algorithms to historical data. In this paper we present applications of different machine learning algorithms in aquaculture applications.

  5. Does Aquaculture Support the Needs of Nutritionally Vulnerable Nations?

    Directory of Open Access Journals (Sweden)

    Christopher D. Golden

    2017-05-01

    Full Text Available Aquaculture now supplies half of the fish consumed directly by humans. We evaluate whether aquaculture, given current patterns of production and distribution, supports the needs of poor and food-insecure populations throughout the world. We begin by identifying 41 seafood-reliant nutritionally vulnerable nations (NVNs, and ask whether aquaculture meets human nutritional demand directly via domestic production or trade, or indirectly via purchase of nutritionally rich dietary substitutes. We find that a limited number of NVNs have domestically farmed seafood, and of those, only specific aquaculture approaches (e.g., freshwater in some locations have the potential to benefit nutritionally vulnerable populations. While assessment of aquaculture's direct contribution via trade is constrained by data limitations, we find that it is unlikely to contribute substantially to human nutrition in vulnerable groups, as most exported aquaculture consists of high-value species for international markets. We also determine that subpopulations who benefit from aquaculture profits are likely not the same subpopulations who are nutritionally vulnerable, and more research is needed to understand the impacts of aquaculture income gains. Finally, we discuss the relationship of aquaculture to existing trends in capture fisheries in NVNs, and suggest strategies to create lasting solutions to nutritional security, without exacerbating existing challenges in access to food and land resources.

  6. 76 FR 9210 - Draft DOC National Aquaculture Policy

    Science.gov (United States)

    2011-02-16

    ... DEPARTMENT OF COMMERCE Draft DOC National Aquaculture Policy AGENCY: Commerce. ACTION: Notice of availability of draft aquaculture policy; request for comments. SUMMARY: The Department of Commerce (DOC) is... United States. The intent of the policy is to guide DOC's actions and decisions on aquaculture and to...

  7. Preliminary investigation on the conversion of aquaculture solid ...

    African Journals Online (AJOL)

    Conversion of aquaculture solid wastes into single cell protein (SCP) for fish feed through solid state fermentation using three fungi species, Aspergilus niger, Trichodema viride and Rhizopus species were investigated. Solid aquaculture waste was collected from the sedimentation unit of a re-circulating aquaculture farm in ...

  8. Digital enclosure and the communication commons revival

    OpenAIRE

    Anderson, Stephen Edward

    2008-01-01

    This thesis considers the political and economic forces shaping the Internet as a medium of increasing importance in everyday life. The digital communications infrastructure is currently facing commercial enclosure on three layers: physical (regulation and ownership of the wires), content (copyright policies, media technology, ownership), and space (ownership and orientation of online tools, spaces, and services). This thesis explores and analyzes the power dynamics driving enclosure on each ...

  9. Marine Spatial Planning Makes Room for Offshore Aquaculture in a Crowded Coastal Zone

    Science.gov (United States)

    Stevens, J.

    2016-12-01

    Offshore aquaculture is an emerging industry predicted to contribute significantly to global seafood production and food security. However, aquaculture farms can generate conflicts by displacing existing ocean user groups and impacting ecosystems. Further, there are multiple farm types with different seafood species, productivity levels and impacts. Thus, it is important to strategically and simultaneously plan farm type and location in relation to the seascape in order to most effectively maximize aquaculture value while also minimizing conflicts and environmental impacts. We address this problem and demonstrate the value of multi-objective planning with a case study that integrates bioeconomic modeling with ecosystem service tradeoff analysis to inform the marine spatial planning (MSP) of mussel, finfish and kelp aquaculture farms in the already-crowded Southern California Bight (SCB) ecosystem. We considered four user groups predicted to conflict with or be impacted by the three types of aquaculture: wild-capture fisheries, ocean viewshed from coastal properties, marine benthic habitat protection, and risk of disease outbreak between farms. Results indicate that significant conflicts and impacts, expected under conventional planning, can be reduced by strategic planning. For example, 28% of potential mussel farm sites overlap with wild-capture halibut fishery grounds, yet MSP can enable mussel aquaculture to generate up to a third of its total potential industry value without impacting halibut fishery yield. Results also highlight hotspot areas in the SCB most appropriate for each type of aquaculture under MSP, as well as particular mussel, finfish and kelp aquaculture spatial plans that align with legislative regulations on allowable impacts from future aquaculture farms in California. This study comprehensively informs aquaculture farm design in the SCB, and demonstrates the value of multi-objective simultaneous planning as a key component in MSP.

  10. Aquaculture Production

    African Journals Online (AJOL)

    Peninah

    strategies for ensuring that Kenya becomes one of the leading producers of fish from aquaculture in ... been only marginally included in the international debate on food security and nutrition. [13]. ... stocked trout into rivers for sport fishing [15].

  11. 30 CFR 56.12026 - Grounding transformer and switchgear enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding transformer and switchgear enclosures... MINES Electricity § 56.12026 Grounding transformer and switchgear enclosures. Metal fencing and metal buildings enclosing transformers and switchgear shall be grounded. ...

  12. Natural convection in asymmetric triangular enclosures heated from below

    International Nuclear Information System (INIS)

    Kamiyo, O M; Angeli, D; Enzo Ferrari, Universita di Modena e Reggio Emilia, via Vignolese 905, I-41125 Modena (Italy))" data-affiliation=" (DIEF – Dipartimento di Ingegneria Enzo Ferrari, Universita di Modena e Reggio Emilia, via Vignolese 905, I-41125 Modena (Italy))" >Barozzi, G S; Collins, M W

    2014-01-01

    Triangular enclosures are typical configurations of attic spaces found in residential as well as industrial pitched-roof buildings. Natural convection in triangular rooftops has received considerable attention over the years, mainly on right-angled and isosceles enclosures. In this paper, a finite volume CFD package is employed to study the laminar air flow and temperature distribution in asymmetric rooftop-shaped triangular enclosures when heated isothermally from the base wall, for aspect ratios (AR) 0.2 ≤ AR ≤ 1.0, and Rayleigh number (Ra) values 8 × 10 5 ≤ Ra ≤ 5 × 10 7 . The effects of Rayleigh number and pitch angle on the flow structure and temperature distributions within the enclosure are analysed. Results indicate that, at low pitch angle, the heat transfer between the cold inclined and the hot base walls is very high, resulting in a multi-cellular flow structure. As the pitch angle increases, however, the number of cells reduces, and the total heat transfer rate progressively reduces, even if the Rayleigh number, being based on the enclosure height, rapidly increases. Physical reasons for the above effect are inspected

  13. From aquaculture goals to real social and ecological impacts: carp introduction in rural Central Mexico.

    Science.gov (United States)

    Tapia, Mónica; Zambrano, Luis

    2003-06-01

    Aquaculture has been seen as a solution to food/protein availability in rural populations of poor countries. It is mainly based on exotic species, that produce changes in host system dynamics once introduced. Aquaculture not only changes the ecology of freshwater systems, but can also lead to modification of social relations. Until now, aquaculture programs have not been adequately analyzed no questioned enough. We evaluate both ecological effects and local social benefits of common carp aquaculture programs in shallow ponds of rural areas, using a municipality in Central Mexico as a case study. Using an "environmental entitlements" approach, our findings suggest that: i) carp aquaculture increases water turbidity and depletes native species reducing the poor people's access to them; ii) aquaculture mainly benefits pond owners rather than poor peasants. This mainly results from changes in fishing rights. We conclude that aquaculture policy goals and assumptions of benefits should be reviewed, if the negative ecological effects are to be decreased and conditions for people in rural areas are to be improved.

  14. Background paper on aquaculture research

    DEFF Research Database (Denmark)

    Wenblad, Axel; Jokumsen, Alfred; Eskelinen, Unto

    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...... vattenbruket and the strategy Svenskt vattenbruk – en grön näring på blå åkrar, Strategi 2012–2020. Implementing the strategy will require a real management of aquaculture that secures the balance between responsibility for the environment and development of aquaculture production. For a significant......, products, etc. 2. Environmental efficient production with trapping of solid waste and balanced nutrient management (recirculation technology, waste heat/green energy/integrated production systems). 3. Policy instruments: legislation, economic incentives, socioeconomic...

  15. Inverness College: Innovations in Aquaculture Training.

    Science.gov (United States)

    Regional Technology Strategies, Inc., Carrboro, NC.

    This paper describes the aquaculture program developed at Inverness College in Scotland. Inverness is located in the Scottish Highlands and serves an area roughly the size of Belgium, but with a population of only 300,000. The regional infrastructure and human capital resources in the Highlands are relatively weak due to inadequate transportation,…

  16. Explosion hazards of LPG-air mixtures in vented enclosure with obstacles.

    Science.gov (United States)

    Zhang, Qi; Wang, Yaxing; Lian, Zhen

    2017-07-15

    Numerical simulations were performed to study explosion characteristics of liquefied petroleum gas (LPG) explosion in enclosure with a vent. Unlike explosion overpressure and dynamic pressure, explosion temperature of the LPG-air mixture at a given concentration in a vented enclosure has very little variation with obstacle numbers for a given blockage ratio. For an enclosure without obstacle, explosion overpressures for the stoichiometric mixtures and the fuel-lean mixtures reach their maximum within the vent and that for fuel-rich mixture reaches its maximum beyond and near the vent. Dynamic pressures produced by an indoor LPG explosion reach their maximum always beyond the vent no matter obstacles are present or not in the enclosure. A LPG explosion in a vented enclosure with built-in obstacles is strong enough to make the brick and mortar wall with a thickness of 370mm damaged. If there is no obstacle in the enclosure, the lower explosion pressure of several kPa can not break the brick and mortar wall with a thickness of 370mm. For a LPG explosion produced in an enclosure with a vent, main hazards, within the vent, are overpressure and high temperature. However main hazards are dynamic pressure, blast wind, and high temperature beyond the vent. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Large fully retractable telescope enclosures still closable in strong wind

    Science.gov (United States)

    Bettonvil, Felix C. M.; Hammerschlag, Robert H.; Jägers, Aswin P. L.; Sliepen, Guus

    2008-07-01

    Two prototypes of fully retractable enclosures with diameters of 7 and 9 m have been built for the high-resolution solar telescopes DOT (Dutch Open Telescope) and GREGOR, both located at the Canary Islands. These enclosures protect the instruments for bad weather and are fully open when the telescopes are in operation. The telescopes and enclosures also operate in hard wind. The prototypes are based on tensioned membrane between movable but stiff bows, which fold together to a ring when opened. The height of the ring is small. The prototypes already survived several storms, with often snow and ice, without any damage, including hurricane Delta with wind speeds up to 68 m/s. The enclosures can still be closed and opened with wind speeds of 20 m/s without any problems or restrictions. The DOT successfully demonstrated the open, wind-flushing concept for astronomical telescopes. It is now widely recognized that also large future telescopes benefit from wind-flushing and retractable enclosures. These telescopes require enclosures with diameters of 30 m until roughly 100 m, the largest sizes for the ELTs (Extreme Large Telescopes), which will be built in the near future. We discuss developments and required technology for the realization of these large sizes.

  18. ZONING OF COASTAL AREA FOR MARINE AQUACULTURE Š PRESENT SITUATIONS AND PROBLEMS

    Directory of Open Access Journals (Sweden)

    Lav Bavčević

    2001-12-01

    Full Text Available We already acepted that Croatian economical and geopolitical possition can bee improved only with better utilization of coastal area. Under these conditions mariculture also makes a part od sea master plan because demands for mariculture are focused on clean environmental conditions to obtain economic benefits. Increased pressure to the coastal area is global trend and if not planed and organized can provoke conflicts and can affect further development. Under these condition, marine aquaculture is frequent subject of many discussion focused on the environmental impact. Conflict of different interest in coastal area with no argumentation is putting marine aquaculture in worst position related with tourism and industry. Hard argumentations is laying in noneadequate frame of work in some facilities and to take advantake competitors are preasenting marine aquaculture in worst picture. Marine aquaculture product has to be health product, which can be completely damaged because of non-responsible approach of other activity. Mariculture also can suffer from self-pollution as for example tourism and must be well planed and managed. Fecal pollution from towns, pollution from bad controlled tourists activity, industry, influence of intensive and non controlled agriculture in coast line, are also potential danger for quality of all sea products and also cultured products from marine aquaculture. High quality of marine products can be obtained by zoning of coastal area, and in concept of these zoning it is necessary to define the zones for marine aquaculture. Procedure of zoning has to be divided in three steps: deetrmination of present status of area, definition of shore land for making mariculture related shore infrastructure and definitions of areas suitable for mariculture with limits of production. These can make positive situations with avoiding conflicts in exploitation of common resources in future. Zone for marine aquaculture has to be controlled

  19. 30 CFR 57.12026 - Grounding transformer and switchgear enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding transformer and switchgear enclosures... NONMETAL MINES Electricity Surface and Underground § 57.12026 Grounding transformer and switchgear enclosures. Metal fencing and metal buildings enclosing transformers and switchgear shall be grounded. ...

  20. Enclosure for handling high activity materials abstract

    International Nuclear Information System (INIS)

    Jimeno de Osso, F.; Dominguez Rodriguez, G.; Cruz Castillo, F. de la; Rodriguez Esteban, A.

    1977-01-01

    One of the most important problems that are met at the laboratories producing and handling radioisotopes is that of designing, building and operating enclosures suitable for the safe handling of active substances. With that purpose in mind, an enclosure has been designed and built for handling moderately high activities under a shielding made of 150 mm thick lead. A description is given of those aspects that may be of interest to people working in this field. (author) [es

  1. Aquaculture disturbance impacts the diet but not ecological linkages of a ubiquitous predatory fish

    Science.gov (United States)

    McPeek, Kathleen C.; McDonald, P. Sean; VanBlaricom, Glenn

    2015-01-01

    Aquaculture operations are a frequent and prominent cause of anthropogenic disturbance to marine and estuarine communities and may alter species composition and abundance. However, little is known about how such disturbances affect trophic linkages or ecosystem functions. In Puget Sound, Washington, aquaculture of the Pacific geoduck clam (Panopea generosa) is increasing and involves placing nets and polyvinyl chloride (PVC) tubes in intertidal areas to protect juvenile geoducks from predators. Initial studies of the structured phase of the farming cycle have documented limited impacts on the abundance of some species. To examine the effect of geoduck aquaculture on ecological linkages, the trophic relationships of a local ubiquitous consumer, Pacific staghorn sculpin (Leptocottus armatus), to its invertebrate prey were compared between geoduck aquaculture sites and nearby reference areas with no aquaculture. Mark-recapture data indicated that sculpin exhibit local site fidelity to cultured and reference areas. The stomach contents of sculpin and stable isotope signatures of sculpin and their prey were examined to study the trophic ecology of cultured and reference areas. Results showed that the structured phase of geoduck aquaculture initiated some changes to staghorn sculpin ecology, as reflected in sculpin diet through stomach content analysis. However, carbon and nitrogen stable isotopes revealed that the general food web function of sculpin remained unchanged. The source of carbon at the base of the food web and the trophic position of sculpin were not impacted by geoduck aquaculture. The study has important implications for geoduck aquaculture management and will inform regulatory decisions related to shellfish aquaculture policy.

  2. Knowledge Enclosures, Forced Specializations and Investment Crisis

    Directory of Open Access Journals (Sweden)

    Filippo Belloc

    2012-12-01

    Full Text Available Like land before the industrial revolution, in the present global economy much knowledge is being enclosed in private hands. In this paper we argue that these enclosures have become a major factor in specialization among firms and among countries: both are forced to specialize in the fields that are not restricted by the enclosures of the others. We use data on 26 OECD countries over the 1978-2006 period. We estimate the effect of patents endowments of countries on their investment specialization across sectors and show that knowledge enclosures involve self-reinforcing innovation patterns. Moreover, we perform a structural change analysis and find that the TRIPs agreement has significantly strengthened the relationship between countries' patents specialization and investment specialization. We conclude by suggesting that stronger international patent protection may restrict global investment opportunities, and this may be one of the factors contributing to the present crisis.

  3. Synthesis of the IRSN report related to the containment of double walled enclosures of the operated fleet

    International Nuclear Information System (INIS)

    2013-01-01

    This report presents the IRSN's analysis on studies and modifications planned by EDF within the frame of the VD3-1300 safety re-examination which more particularly concern the third containment barrier of a reactor and of its extensions, as well as the containment of some surrounding buildings. The addressed topics are: the approach associated with the 'containment' safety function, the condition, behaviour and control of the double walled enclosure, the system of suction and filtration of the space between enclosures, the extension of the third containment barrier, the containment of building surrounding the reactor building, the risk of bypass containment, the EDF organisation with respect to the containment safety function

  4. Theoretical Characterization of Enclosures

    Czech Academy of Sciences Publication Activity Database

    Rohn, Jiří

    2016-01-01

    Roč. 21, October (2016), s. 140-145 ISSN 1573-1340 Institutional support: RVO:67985807 Keywords : interval linear equations * solution set * enclosure * component * characterization Subject RIV: BA - General Mathematics http://interval.louisiana.edu/reliable-computing-journal/volume-21/reliable-computing-21-pp-140-145.pdf

  5. 40 CFR 86.1217-96 - Evaporative emission enclosure calibrations.

    Science.gov (United States)

    2010-07-01

    ... procedure: (1) Carefully measure the internal length, width and height of the enclosure, accounting for... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Evaporative emission enclosure calibrations. 86.1217-96 Section 86.1217-96 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  6. Economic impact studies on development project of New Yogyakarta International Airport to aquaculture in Kulonprogo Coastal

    Science.gov (United States)

    Rachman, F.; Satriagasa, M. C.; Riasasi, W.

    2018-03-01

    New Yogyakarta International Airport (NYIA) is being constructed in Temon Sub District, Kulonprogo District. It lies on 587.2 ha area in the southern part of Java Island coastal area. Many areas of Kulonprogro coastal area are used for aquaculture of vanname shrimp. In that case, the aquaculture land needs to be cleared for the airport construction necessity and requires compensation. The value of the compensation needs to be right calculated by both sides, regarding the aquaculture land are local community assets. This study uses spatial analysis and visual interpretation. Whereas, the calculation of the acquisition value and income capital value uses Discounted Cash Flow (DCF) method. The result shows the area of aquaculture land which impacted to be cleared is 83 ha, means decreasing of shrimp ponds area in Temon Sub District, Kulonprogo District. The calculation of acquisition value for airport development indicates higher value than the income from the aquaculture activity. The results mean the aquaculture landlords do not incur losses due to the airport development project. These findings can be used for local government and related stakeholders to formulate a policy of aquaculture relocation and to estimate projection for aquaculture land suitability in Yogyakarta coastal area.

  7. Recent Major Advances of Biotechnology and Sustainable Aquaculture in China

    Science.gov (United States)

    Xiang, Jianhai

    2015-01-01

    Background: Global aquaculture production has increased continuously over the last five decades, and particularly in China. Its aquaculture has become the fastest growing and most efficient agri-sector, with production accounting for more than 70% of the world’s aquaculture output. In the new century, with serious challenges regarding population, resources and the environment, China has been working to develop high-quality, effective, healthy, and sustainable blue agriculture through the application of modern biotechnology. Sound knowledge related to the biology and ecology of aquatic organisms has laid a solid foundation and provided the innovation and technology for rapid development of the aquaculture industry. Marine biotechnology, which is enabling solutions for ocean productivity and sustainability, has been promoted since the last decades of the 20th Century in China. Objective: In this article, priority areas of research, mainly genetic breeding, omics studies, novel production systems, biosecurity, bioprocesses and biorefinery, as well as the major progress of marine biotechnology R&D in China are reviewed. Conclusion: Current innovative achievements in China are not enough and the level and frequency of academic advancements must be improved. International cooperation and assistance remain crucial for the success of marine biotechnology. PMID:28553577

  8. Aquaculture intérieure et adaptation aux changements climatiques ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gender and the management of climate-related risks in northern Thailand. Papers. Risk aversion and emotions in the management of climate-related risks by fish farmers. Papers. Mainstreaming climate change into inland aquaculture policies in Thailand. Papers. Improving climate risk management as an adaptation ...

  9. Measurements of density profile evolution during the stably-stratified filling of an open enclosure

    International Nuclear Information System (INIS)

    Tarawneh, Constantine M.; Homan, K.O.

    2008-01-01

    The stably-stratified filling of an open enclosure produces an interfacial gradient layer which is transported through the enclosure with the bulk flow. The evolution of this interfacial layer is strongly time-dependent and is driven by the nature of the interaction between the internal gravity waves and the inlet-driven interfacial shear. Measurements of density profile evolution have been completed for a rectangular enclosure with a single corner inlet and density variation produced by saline concentration. This system serves as a mass transfer analog to large-scale, thermally-stratified energy storage devices, preserving dynamic similitude in a laboratory-scale system. The experiments covered jet Reynolds numbers of 200-2200 and Froude numbers of 0.06-0.6 in an enclosure with a width 23 times the jet inlet height. The density profiles are seen to be strongly asymmetric and exhibit growth rates significantly different than due to simple one-dimensional molecular diffusion. In addition, shadowgraph and hydrogen bubble visualizations of the density and velocity fields in the gradient layer show the persistence of complex multi-dimensional flow structure even at relatively late stages of the filling process when the gradient layer has been transported well away from the enclosure inlet. The evolution of the vertical density profile has been compared quantitatively to a quasi one-dimensional model based upon empirical diffusivity coefficients

  10. Sound reduction by metamaterial-based acoustic enclosure

    Directory of Open Access Journals (Sweden)

    Shanshan Yao

    2014-12-01

    Full Text Available In many practical systems, acoustic radiation control on noise sources contained within a finite volume by an acoustic enclosure is of great importance, but difficult to be accomplished at low frequencies due to the enhanced acoustic-structure interaction. In this work, we propose to use acoustic metamaterials as the enclosure to efficiently reduce sound radiation at their negative-mass frequencies. Based on a circularly-shaped metamaterial model, sound radiation properties by either central or eccentric sources are analyzed by numerical simulations for structured metamaterials. The parametric analyses demonstrate that the barrier thickness, the cavity size, the source type, and the eccentricity of the source have a profound effect on the sound reduction. It is found that increasing the thickness of the metamaterial barrier is an efficient approach to achieve large sound reduction over the negative-mass frequencies. These results are helpful in designing highly efficient acoustic enclosures for blockage of sound in low frequencies.

  11. Sound reduction by metamaterial-based acoustic enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Shanshan; Li, Pei; Zhou, Xiaoming; Hu, Gengkai, E-mail: hugeng@bit.edu.cn [Key Laboratory of Dynamics and Control of Flight Vehicle, Ministry of Education and School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081 (China)

    2014-12-15

    In many practical systems, acoustic radiation control on noise sources contained within a finite volume by an acoustic enclosure is of great importance, but difficult to be accomplished at low frequencies due to the enhanced acoustic-structure interaction. In this work, we propose to use acoustic metamaterials as the enclosure to efficiently reduce sound radiation at their negative-mass frequencies. Based on a circularly-shaped metamaterial model, sound radiation properties by either central or eccentric sources are analyzed by numerical simulations for structured metamaterials. The parametric analyses demonstrate that the barrier thickness, the cavity size, the source type, and the eccentricity of the source have a profound effect on the sound reduction. It is found that increasing the thickness of the metamaterial barrier is an efficient approach to achieve large sound reduction over the negative-mass frequencies. These results are helpful in designing highly efficient acoustic enclosures for blockage of sound in low frequencies.

  12. A Numerical Study of Fluid Flow and Heat Transfer in Carbon Dioxide Enclosures on Mars

    Directory of Open Access Journals (Sweden)

    Yue Sun

    2018-03-01

    Full Text Available In order to support the future thermal control and energy conservation design for the Mars rover, numerical studies on natural convection in CO2 enclosures on Mars’ surface were conducted for both horizontal and vertical enclosures. The parameters are as follows: the atmospheric pressure was 1000 Pa, the gravitational acceleration was 3.62 m/s2, and the Prandtl number was 0.77. The heat flux, temperature, and velocity fields of the CO2 enclosures were obtained with the aspect ratio ranging from 5.56 to 200 and the Grashof number ranging from 430 to 2.6 × 104. It was found that natural convection formed more easily in the horizontal enclosures than that in the vertical enclosures when the enclosures had same thickness. With the increasing thickness of the enclosures, Rayleigh–Bénard convections formed in the horizontal enclosures, while only single-cell convections formed in the vertical enclosures. The heat flux through the horizontal enclosures was greater than that through the vertical enclosures with the same thickness when natural convection formed. The maximum difference between them reached 35.26%, which was illustrated by the field synergy principle. A hysteresis phenomenon of the natural convection dominating the heat transfer was found in the vertical enclosure on Mars’ surface. New values for the critical Grashof number and correlations for the average Nusselt number for both the horizontal and vertical CO2 enclosures on Mars’ surface were also developed.

  13. Antibacterial Resistance in African Catfish Aquaculture: a Review

    Directory of Open Access Journals (Sweden)

    Madubuike U. ANYANWU

    2016-03-01

    Full Text Available Antibacterial resistance (AR is currently one of the greatest threats to mankind as it constitutes health crisis. Extensive use of antibacterial agents in human and veterinary medicine, and farm crops have resulted in emergence of antibacterial-resistant organisms in different environmental settings including aquaculture. Antibacterial resistance in aquaculture is a serious global concern because antibacterial resistance genes (ARGs can be transferred easily from aquaculture setting to other ecosystems and the food chain. African catfish (ACF aquaculture has increased at a phenomenal rate through a continuous process of intensification, expansion and diversification. Risk of bacterial diseases has also increased and consequently there is increased use of antibacterial agents for treatment. Antibacterial resistance in ACF aquaculture has huge impact on the food chain and thus represents risk to public and animal health. In “one health” approach of curbing AR, knowledge of the sources, mechanisms and magnitude of AR in ACF aquaculture and its potential impact on the food chain is important in designing and prioritizing monitoring programs that may generate data that would be relevant for performing quantitative risk assessments, implementation of antibacterial stewardship plans, and developing effective treatment strategies for the control of ACF disease and reducing risk to public health. This review provides insight on the sources, mechanisms, prevalence and impact of antibacterial resistance in ACF aquaculture environment, a setting where the impact of AR is neglected or underestimated.

  14. Aquaculture intérieure et adaptation aux changements climatiques ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Risk aversion and emotions in the management of climate-related risks by fish farmers. IDL-56181.pdf. Papers. Climate-related risks to cage aquaculture in the reservoirs of Northern Thailand. IDL-56141.pdf. Papers. Weighing Costs, Weathering Risks: Adaptive Strategies of Fish Farmers Facing Multiple Risks in Northern ...

  15. 46 CFR 154.195 - Aluminum cargo tank: Steel enclosure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Aluminum cargo tank: Steel enclosure. 154.195 Section... Equipment Hull Structure § 154.195 Aluminum cargo tank: Steel enclosure. (a) An aluminum cargo tank and its... the aluminum cargo tank must meet the steel structural standards of the American Bureau of Shipping...

  16. Use of antimicrobial agents in aquaculture.

    Science.gov (United States)

    Park, Y H; Hwang, S Y; Hong, M K; Kwon, K H

    2012-04-01

    The aquaculture industry has grown dramatically, and plays an important role in the world's food supply chain. Antimicrobial resistance in bacteria associated with food animals receives much attention, and drug use in aquaculture is also an important issue. There are many differences between aquatic and terrestrial management systems, such as the methods used for administration of drugs. Unique problems are related to the application of drugs in aquatic environments. Residual drugs in fish products can affect people who consume them, and antimicrobials released into aquatic environments can select for resistant bacteria. Moreover, these antimicrobial-resistant bacteria, or their resistance genes, can be transferred to humans. To decrease the risks associated with the use of antimicrobials, various regulations have been developed. In addition, it is necessary to prevent bacterial diseases in aquatic animals by vaccination, to improve culture systems, and to monitor the amount of antimicrobial drugs used and the prevalence of antimicrobial-resistant bacteria.

  17. Numerical Simulation of Transient Moisture Transfer into an Electronic Enclosure

    DEFF Research Database (Denmark)

    Shojaee Nasirabadi, Parizad; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisturetransfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermalstresses. It is therefore essential to study the local climate...... inside the enclosures to be able to protect the electronic systems.In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce theCPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which...

  18. The aquaculture potential of Tilapia rendalli in relation to its feeding habits and digestive capabilities

    Science.gov (United States)

    Hlophe, S. N.; Moyo, N. A. G.

    Tilapia rendalli is a predominately macrophagous fish. However, it was able to colonise an oligotrophic dam (Flag Boshielo) with limited macrophytes. Therefore, the diet of T. rendalli in this dam was investigated; its stomach contents were examined over 12 months. A size related dietary shift was evident. Juveniles fed mainly on zooplankton while sub-adult and adult fish grazed on both macrophytes and marginal vegetation. T. rendalli’s ability to strive in an environment with limited food resources led to a subsequent study to determine its aquaculture potential. Its growth performance was compared to that of the commonly cultured Oreochromis mossambicus. Juveniles of both species were fed a commercial tilapia diet for 60 days. Specific growth rate and protein efficiency ratio was comparable to that of O. mossambicus (P > 0.05, ANOVA). Feed conversion ratio was significantly higher (P 0.05). Amylase activities were significantly higher (P < 0.05) in T. rendalli than in O. mossambicus. The highest amylase activities were recorded in the proximal intestines as 26.34 and 22.00 μmol/min/mg protein in T. rendalli and O. mossambicus respectively. This may be an indicator that T. rendalli is better equipped to digest plant diets. T. rendalli may be the aquaculture species of choice for emerging fish farmers who cannot afford the highly priced fishmeal as a protein source in fish diets.

  19. 49 CFR 193.2905 - Protective enclosures.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS FACILITIES... surrounded by a protective enclosure: (1) Storage tanks; (2) Impounding systems; (3) Vapor barriers; (4...

  20. Test plan for engineering scale electrostatic enclosure demonstration

    International Nuclear Information System (INIS)

    Meyer, L.C.

    1993-02-01

    This test plan describes experimental details of an engineering-scale electrostatic enclosure demonstration to be performed at the Idaho National Engineering Laboratory in fiscal year (FY)-93. This demonstration will investigate, in the engineering scale, the feasibility of using electrostatic enclosures and devices to control the spread of contaminants during transuranic waste handling operations. Test objectives, detailed experimental procedures, and data quality objectives necessary to perform the FY-93 experiments are included in this plan

  1. Effects of Power Lines on Area Use and Behaviour of Semi-Domestic Reindeer in Enclosures

    International Nuclear Information System (INIS)

    Flydal, K.; Reimers, E.; Johansen, F.; Colman, J.E.; Korslund, L.; Colman, J.E.

    2009-01-01

    We conducted large-scale, replicated experiments to test the effects of two parallel power lines on area use, behaviour, and activity of semidomestic reindeer in enclosures. Yearling female reindeer were released into four 50 x 400 m enclosures; two treatment enclosures with power lines and two control enclosures. Reindeer from two herds, one from Kautokeino (domestic tame) and one from Vaga, (domestic wild) were tested separately and compared. Individual location within the enclosures was not affected by the power lines. Effects on restless behaviour were ambiguous, with slightly more restless behaviour in the treatment enclosures for the domestic tame reindeer, while the domestic wild reindeer maintained a stable level in the treatment enclosures, increasing with time in the control enclosures. Activity changes were slightly more common among animals within treatment enclosures for both herds, with no indication of habituation during the experiment. The domestic wild reindeer had more than three times the amount of restless behaviour than the domestic tame reindeer. Our study indicates that for reindeer in enclosures, the disturbance from a power line construction is negligible. This suggests that power lines are a minor disturbing factor compared to human handling when using fenced in areas like grazing gardens in reindeer husbandry.

  2. Impacts, Perceptions and Management of Climate-Related Risks to Cage Aquaculture in the Reservoirs of Northern Thailand.

    Science.gov (United States)

    Lebel, Louis; Lebel, Phimphakan; Lebel, Boripat

    2016-12-01

    Weather is suspected to influence fish growth and survival, and be a factor in mass mortality events in cage aquaculture in reservoirs. The purpose of this study was to identify the important climate-related risks faced by cage aquaculture farms; evaluate how these risks were currently being managed; and explore how farmers might adapt to the effects of climate change. Fish farmers were interviewed across the northern region of Thailand to get information on impacts, perceptions and practices. Drought or low water levels, heat waves, cold spells and periods with dense cloud cover, each caused significant financial losses. Perceptions of climate-related risks were consistent with experienced impacts. Risks are primarily managed in the short-term with techniques like aeration and reducing feed. In the mid-term farmers adjust stocking calendars, take financial measures and seek new information. Farmers also emphasize the importance of maintaining good relations with other stakeholders and reservoir management. Larger farms placed greater importance on risk management than small farms, even though types and levels of risk perceived were very similar. Most fish farms were managed by men alone, or men and women working together. Gender differences in risk perception were not detected, but women judged a few risk management practices as more important than men. Fish farmers perceived that climate is changing, but their perceptions were not strongly associated with recently having suffered impacts from extreme weather. The findings of this study provide important inputs to improving risk management under current and future climate.

  3. Salmon Aquaculture and Antimicrobial Resistance in the Marine Environment

    Science.gov (United States)

    Buschmann, Alejandro H.; Tomova, Alexandra; López, Alejandra; Maldonado, Miguel A.; Henríquez, Luis A.; Ivanova, Larisa; Moy, Fred; Godfrey, Henry P.; Cabello, Felipe C.

    2012-01-01

    Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a salmon farm and at a control site 8 km distant without observable aquaculture activities. Three antimicrobials extensively used in Chilean salmon aquaculture (oxytetracycline, oxolinic acid, and florfenicol) were studied. Although none of these antimicrobials was detected in sediments from either site, traces of flumequine, a fluoroquinolone antimicrobial also widely used in Chile, were present in sediments from both sites during this period. There were significant increases in bacterial numbers and antimicrobial-resistant fractions to oxytetracycline, oxolinic acid, and florfenicol in sediments from the aquaculture site compared to those from the control site. Interestingly, there were similar numbers of presumably plasmid-mediated resistance genes for oxytetracycline, oxolinic acid and florfenicol in unselected marine bacteria isolated from both aquaculture and control sites. These preliminary findings in one location may suggest that the current use of large amounts of antimicrobials in Chilean aquaculture has the potential to select for antimicrobial-resistant bacteria in marine sediments. PMID:22905164

  4. Salmon aquaculture and antimicrobial resistance in the marine environment.

    Directory of Open Access Journals (Sweden)

    Alejandro H Buschmann

    Full Text Available Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a salmon farm and at a control site 8 km distant without observable aquaculture activities. Three antimicrobials extensively used in Chilean salmon aquaculture (oxytetracycline, oxolinic acid, and florfenicol were studied. Although none of these antimicrobials was detected in sediments from either site, traces of flumequine, a fluoroquinolone antimicrobial also widely used in Chile, were present in sediments from both sites during this period. There were significant increases in bacterial numbers and antimicrobial-resistant fractions to oxytetracycline, oxolinic acid, and florfenicol in sediments from the aquaculture site compared to those from the control site. Interestingly, there were similar numbers of presumably plasmid-mediated resistance genes for oxytetracycline, oxolinic acid and florfenicol in unselected marine bacteria isolated from both aquaculture and control sites. These preliminary findings in one location may suggest that the current use of large amounts of antimicrobials in Chilean aquaculture has the potential to select for antimicrobial-resistant bacteria in marine sediments.

  5. Radiation exchange factors between specular inner surfaces of a rectangular enclosure such as transplant production unit

    International Nuclear Information System (INIS)

    Abdel-Ghany, Ahmed M.; Kozai, Toyoki

    2006-01-01

    General mathematical relations are presented for the specular exchange factors, F S , of diffuse radiation exchange between the inner surfaces of a rectangular enclosure. Three of these surfaces are specular reflectors, diffuse emitters and the fourth surface is a diffuse reflector, diffuse emitter. This enclosure can be used as a transplant production unit with artificial lighting for electric energy saving purposes. An image system and the crossed string method are used to derive these relations. The resulting expressions are conceptually simple and similar to the commonly known expressions of the exchange factors between diffuse surfaces, F. The accuracy of the presented F S relations was examined for different numbers of multiple reflections, N, on the specular surfaces and for different aspect ratios (ratio of the width, w to the height, h). The results proved that the relations are accurate and strongly satisfy the well-known relation of the radiation exchange between enclosure surfaces and satisfy the reciprocity relation. For any aspect ratio, considering N of 150 between highly reflective surfaces (ρ = 0.99) is sufficient to estimate the F S factors without any possible error. Using specular reflecting surfaces in such cases significantly reduces the electric energy consumption used for lighting

  6. Exploring Aquaculture. Curriculum Guide for Agriscience 282.

    Science.gov (United States)

    Texas A and M Univ., College Station. Dept. of Agricultural Education.

    This curriculum guide provides materials for teachers to use in developing a course in "Exploring Aquaculture, Agriscience 282," one of 28 semester courses in agricultural science and technology for Texas high schools. This introductory course is designed to acquaint students with the growing industry of aquaculture; it includes…

  7. Thermal Transmission through Existing Building Enclosures: Destructive Monitoring in Intermediate Layers versus Non-Destructive Monitoring with Sensors on Surfaces.

    Science.gov (United States)

    Echarri, Víctor; Espinosa, Almudena; Rizo, Carlos

    2017-12-08

    Opaque enclosures of buildings play an essential role in the level of comfort experienced indoors and annual energy demand. The impact of solar radiation and thermal inertia of the materials that make up the multi-layer enclosures substantially modify thermal transmittance behaviour of the enclosures. This dynamic form of heat transfer, additionally affected by indoor HVAC systems, has a substantial effect on the parameters that define comfort. It also has an impact on energy demand within a daily cycle as well as throughout a one-year use cycle. This study describes the destructive monitoring of an existing block of flats located in Alicante. Once the enclosure was opened, sensors of temperature (PT100), air velocity, and relative humidity were located in the different layers of the enclosure, as well as in the interior and exterior surfaces. A pyranometer was also installed to measure solar radiation levels. A temperature data correction algorithm was drawn up to address irregularities produced in the enclosure. The algorithm was applied using a Raspberry Pi processor in the data collection system. The comparative results of temperature gradients versus non-destructive monitoring systems are presented, providing measures of the transmittance value, surface temperatures and indoor and outdoor air temperatures. This remote sensing system can be used in future studies to quantify and compare the energy savings of different enclosure construction solutions.

  8. Thermal Transmission through Existing Building Enclosures: Destructive Monitoring in Intermediate Layers versus Non-Destructive Monitoring with Sensors on Surfaces

    Directory of Open Access Journals (Sweden)

    Víctor Echarri

    2017-12-01

    Full Text Available Opaque enclosures of buildings play an essential role in the level of comfort experienced indoors and annual energy demand. The impact of solar radiation and thermal inertia of the materials that make up the multi-layer enclosures substantially modify thermal transmittance behaviour of the enclosures. This dynamic form of heat transfer, additionally affected by indoor HVAC systems, has a substantial effect on the parameters that define comfort. It also has an impact on energy demand within a daily cycle as well as throughout a one-year use cycle. This study describes the destructive monitoring of an existing block of flats located in Alicante. Once the enclosure was opened, sensors of temperature (PT100, air velocity, and relative humidity were located in the different layers of the enclosure, as well as in the interior and exterior surfaces. A pyranometer was also installed to measure solar radiation levels. A temperature data correction algorithm was drawn up to address irregularities produced in the enclosure. The algorithm was applied using a Raspberry Pi processor in the data collection system. The comparative results of temperature gradients versus non-destructive monitoring systems are presented, providing measures of the transmittance value, surface temperatures and indoor and outdoor air temperatures. This remote sensing system can be used in future studies to quantify and compare the energy savings of different enclosure construction solutions.

  9. Thermal Transmission through Existing Building Enclosures: Destructive Monitoring in Intermediate Layers versus Non-Destructive Monitoring with Sensors on Surfaces

    Science.gov (United States)

    Echarri, Víctor; Espinosa, Almudena; Rizo, Carlos

    2017-01-01

    Opaque enclosures of buildings play an essential role in the level of comfort experienced indoors and annual energy demand. The impact of solar radiation and thermal inertia of the materials that make up the multi-layer enclosures substantially modify thermal transmittance behaviour of the enclosures. This dynamic form of heat transfer, additionally affected by indoor HVAC systems, has a substantial effect on the parameters that define comfort. It also has an impact on energy demand within a daily cycle as well as throughout a one-year use cycle. This study describes the destructive monitoring of an existing block of flats located in Alicante. Once the enclosure was opened, sensors of temperature (PT100), air velocity, and relative humidity were located in the different layers of the enclosure, as well as in the interior and exterior surfaces. A pyranometer was also installed to measure solar radiation levels. A temperature data correction algorithm was drawn up to address irregularities produced in the enclosure. The algorithm was applied using a Raspberry Pi processor in the data collection system. The comparative results of temperature gradients versus non-destructive monitoring systems are presented, providing measures of the transmittance value, surface temperatures and indoor and outdoor air temperatures. This remote sensing system can be used in future studies to quantify and compare the energy savings of different enclosure construction solutions. PMID:29292781

  10. A comprehensive survey on selective breeding programs and seed market in the European aquaculture fish industry

    NARCIS (Netherlands)

    Chavanne, Hervé; Janssen, K.P.E.; Hofherr, Johann; Contini, Franca; Haffray, P.; Komen, J.; Nielsen, E.E.; Bargelloni, L.

    2016-01-01

    The use of selective breeding is still relatively limited in aquaculture species. Information on such activities is sparse, hindering an overall evaluation of their success. Here, we report on the results of an online survey of the major aqua-culture breeding companies operating in Europe. Six main

  11. 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.

  12. A research update for the Stuttgart National Aquaculture Research Center

    Science.gov (United States)

    Aquaculture (fish farming) has played an ever-increasing role in providing people with fish, shrimp, and shellfish. Aquaculture is currently the fastest growing sector of global food production and in 2016 totaled 90 million tons valued at $180 billion. The production of food-fish from aquaculture...

  13. Methane and Nitrous Oxide Emissions Reduced Following Conversion of Rice Paddies to Inland Crab-Fish Aquaculture in Southeast China.

    Science.gov (United States)

    Liu, Shuwei; Hu, Zhiqiang; Wu, Shuang; Li, Shuqing; Li, Zhaofu; Zou, Jianwen

    2016-01-19

    Aquaculture is an important source of atmospheric methane (CH4) and nitrous oxide (N2O), while few direct flux measurements are available for their regional and global source strength estimates. A parallel field experiment was performed to measure annual CH4 and N2O fluxes from rice paddies and rice paddy-converted inland crab-fish aquaculture wetlands in southeast China. Besides N2O fluxes dependent on water/sediment mineral N and CH4 fluxes related to water chemical oxygen demand, both CH4 and N2O fluxes from aquaculture were related to water/sediment temperature, sediment dissolved organic carbon, and water dissolved oxygen concentration. Annual CH4 and N2O fluxes from inland aquaculture averaged 0.37 mg m(-2) h(-1) and 48.1 μg m(-2) h(-1), yielding 32.57 kg ha(-1) and 2.69 kg N2O-N ha(-1), respectively. The conversion of rice paddies to aquaculture significantly reduced CH4 and N2O emissions by 48% and 56%, respectively. The emission factor for N2O was estimated to be 0.66% of total N input in the feed or 1.64 g N2O-N kg(-1) aquaculture production in aquaculture. The conversion of rice paddies to inland aquaculture would benefit for reconciling greenhouse gas mitigation and agricultural income increase as far as global warming potentials and net ecosystem economic profits are of concomitant concern. Some agricultural practices such as better aeration and feeding, and fallow season dredging would help to lower CH4 and N2O emissions from inland aquaculture. More field measurements from inland aquaculture are highly needed to gain an insight into national and global accounting of CH4 and N2O emissions.

  14. Aquaculture Asia, Vol. 8, No. 1, pp.1-58, January-March 2003

    OpenAIRE

    2003-01-01

    *Table of Contents* Sustainable Aquaculture Fertilization, soil and water quality management in small-scale ponds part II:Soil and water quality management S. Adhikari Fisheries and aquaculture activities in Nepal Tek Gurung Peter Edwards writes on rural aquaculture: A knowledge-base for rural aquaculture Farmers as Scientists: Commercialization of giant freshwater prawn culture in India M.C. Nandeesha Aquaculture in reservoir fed canal based irrigation systems of I...

  15. Construction of Lightweight Loudspeaker Enclosures

    DEFF Research Database (Denmark)

    Juul-Nyholm, Herle Bagh; Severinsen, Jonas Corfitz; Schneider, Henrik

    2017-01-01

    On the basis of bass cabinets, this paper deals with the problem of reducing loudspeaker enclosure weight. An introductory market analysis emphasizes that lighter cabinets are sought, but maintenance of sound quality is vital. The problem is challenged through experiments and simulations in COMSO...

  16. Reactor enclosure. BRC meeting presentation

    International Nuclear Information System (INIS)

    Fisch, J.W.

    1975-01-01

    The latest status of key components of the Reactor Enclosure System of the Clinch River Breeder Reactor Plant is described. Areas where there have been notable design changes or significant design detail maturity in the six months since the last BRC presentation are highlighted. (auth)

  17. 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.

  18. Rigorous high-precision enclosures of fixed points and their invariant manifolds

    Science.gov (United States)

    Wittig, Alexander N.

    The well established concept of Taylor Models is introduced, which offer highly accurate C0 enclosures of functional dependencies, combining high-order polynomial approximation of functions and rigorous estimates of the truncation error, performed using verified arithmetic. The focus of this work is on the application of Taylor Models in algorithms for strongly non-linear dynamical systems. A method is proposed to extend the existing implementation of Taylor Models in COSY INFINITY from double precision coefficients to arbitrary precision coefficients. Great care is taken to maintain the highest efficiency possible by adaptively adjusting the precision of higher order coefficients in the polynomial expansion. High precision operations are based on clever combinations of elementary floating point operations yielding exact values for round-off errors. An experimental high precision interval data type is developed and implemented. Algorithms for the verified computation of intrinsic functions based on the High Precision Interval datatype are developed and described in detail. The application of these operations in the implementation of High Precision Taylor Models is discussed. An application of Taylor Model methods to the verification of fixed points is presented by verifying the existence of a period 15 fixed point in a near standard Henon map. Verification is performed using different verified methods such as double precision Taylor Models, High Precision intervals and High Precision Taylor Models. Results and performance of each method are compared. An automated rigorous fixed point finder is implemented, allowing the fully automated search for all fixed points of a function within a given domain. It returns a list of verified enclosures of each fixed point, optionally verifying uniqueness within these enclosures. An application of the fixed point finder to the rigorous analysis of beam transfer maps in accelerator physics is presented. Previous work done by

  19. The use of probiotics in aquaculture.

    Science.gov (United States)

    Hai, N V

    2015-10-01

    This study aims to present comprehensive notes for the use of probiotics in aquaculture. Probiotics have been proven to be positive promoters of aquatic animal growth, survival and health. In aquaculture, intestines, gills, the skin mucus of aquatic animals, and habitats or even culture collections and commercial products, can be sources for acquiring appropriate probiotics, which have been identified as bacteria (Gram-positive and Gram-negative) and nonbacteria (bacteriophages, microalgae and yeasts). While a bacterium is a pathogen to one aquatic animal, it can bring benefits to another fish species; a screening process plays a significant role in making a probiotic species specific. The administration of probiotics varies from oral/water routine to feed additives, of which the latter is commonly used in aquaculture. Probiotic applications can be either mono or multiple strains, or even in combination with prebiotic, immunostimulants such as synbiotics and synbiotism, and in live or dead forms. Encapsulating probiotics with live feed is a suitable approach to convey probiotics to aquatic animals. Dosage and duration of time are significant factors in providing desired results. Several modes of actions of probiotics are presented, while some others are not fully understood. Suggestions for further studies on the effects of probiotics in aquaculture are proposed. © 2015 The Society for Applied Microbiology.

  20. The Effects of Spatial Enclosure on Social Interaction Between Older Adults With Dementia and Young Children.

    Science.gov (United States)

    Cerruti, Minyoung S; Shepley, Mardelle M

    2016-04-01

    To examine the impact of spatial enclosures on social interaction between older adults with early stage dementia and young children. Intergenerational interaction through meaningful activities can promote positive affects and behaviors of children and older adults. The development of social interaction is closely related to the physical environment in association with personal competence of older adults with dementia and young children. However, minimal attention has been given to the role of physical environment in influencing intergenerational interaction. A quasi-experiment examined the functional relationship between the amount of spatial enclosure and the types of social behaviors of older adults with dementia and young children. Semi-structured interviews, aided by a photographic simulation, were developed to explore the participants' perceptions of and experiences with the different degrees of spatial enclosure. Findings showed that the semienclosed spatial plan impacted both prosocial and antisocial behaviors of older adults with dementia in their interactions with young children. This apparent discrepancy was associated with two conflicting perceptions: a sense of openness and the lack of control due to distraction created by the loose visual boundary. There was no correlation between the elder-child neutral behaviors and the degrees of spatial enclosure. This study suggests that spaces with moderate openness without visual and acoustic distraction are the most desirable to promote prosocial behaviors of older adults with dementia and young children. Additionally, elder-child prosocial behaviors were likely facilitated by specific design features such as adequate personal space, the perception of openness, and possible spaces that provide both prospect and refuge in relation to spatial enclosure. © The Author(s) 2016.

  1. Aquaculture in South Africa: A cooperative research programme

    CSIR Research Space (South Africa)

    Safriel, O

    1984-06-01

    Full Text Available the industry on a sound footing. An Aquaculture Working Group was appointed by the CSIR in 1981, which developed a research strategy, identified needs and suggested priorities for research on major problem areas in aquaculture....

  2. Certify Sustainable Aquaculture?

    DEFF Research Database (Denmark)

    Bush, Simon; Belton, Ben; Hall, Derek

    2013-01-01

    ) 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....

  3. An Overview of Aquaculture in the Nordic Countries

    DEFF Research Database (Denmark)

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

    2010-01-01

    in the Nordic countries has a long history; beginning in the 1850s when hatcheries for restocking of salmon and trout were established in Norway. Nowadays, Atlantic salmon is the dominant cultured species in Norway and the Faroe Islands, whereas rainbow trout dominate in Denmark, Finland, and Sweden. Arctic......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...

  4. THE FISHERIES AND AQUACULTURE COMPONENT OF RURAL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Adrian ZUGRAVU

    2006-01-01

    Full Text Available Fisheries and aquaculture can provide a key contribution to food security and poverty alleviation. Fisheries and aquaculture policy is an instrument for the conservation and management of fisheries and aquaculture. It was created with the aims of managing a common resource. Fisheries policies and management strategies the world over is in a state of flux, continued attempts to use fisheriesas the key to solving a complex web of social and economic issues threaten to overwhelm the basic fact that, if this resources are overfished, they will not sustain either social or development.

  5. Hybrid governance of aquaculture: Opportunities and challenges.

    Science.gov (United States)

    Vince, Joanna; Haward, Marcus

    2017-10-01

    The development of third party assessment and certification of fisheries and aquaculture has provided new forms of governance in sectors that were traditionally dominated by state based regulation. Emerging market based approaches are driven by shareholder expectations as well as commitment to corporate social responsibility, whereas community engagement is increasingly centered on the questions of social license to operate. Third party assessment and certification links state, market and community into an interesting and challenging hybrid form of governance. While civil society organizations have long been active in pursuing sustainable and safe seafood production, the development of formal non-state based certification provides both opportunities and challenges, and opens up interesting debates over hybrid forms of governance. This paper explores these developments in coastal marine resources management, focusing on aquaculture and the development and operation of the Aquaculture Stewardship Council. It examines the case of salmonid aquaculture in Tasmania, Australia, now Australia's most valuable seafood industry, which remains the focus of considerable community debate over its siting, operation and environmental impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Problems of large-scale vertically-integrated aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Webber, H H; Riordan, P F

    1976-01-01

    The problems of vertically-integrated aquaculture are outlined; they are concerned with: species limitations (in the market, biological and technological); site selection, feed, manpower needs, and legal, institutional and financial requirements. The gaps in understanding of, and the constraints limiting, large-scale aquaculture are listed. Future action is recommended with respect to: types and diversity of species to be cultivated, marketing, biotechnology (seed supply, disease control, water quality and concerted effort), siting, feed, manpower, legal and institutional aids (granting of water rights, grants, tax breaks, duty-free imports, etc.), and adequate financing. The last of hard data based on experience suggests that large-scale vertically-integrated aquaculture is a high risk enterprise, and with the high capital investment required, banks and funding institutions are wary of supporting it. Investment in pilot projects is suggested to demonstrate that large-scale aquaculture can be a fully functional and successful business. Construction and operation of such pilot farms is judged to be in the interests of both the public and private sector.

  7. Annual methane and nitrous oxide emissions from rice paddies and inland fish aquaculture wetlands in southeast China

    Science.gov (United States)

    Wu, Shuang; Hu, Zhiqiang; Hu, Tao; Chen, Jie; Yu, Kai; Zou, Jianwen; Liu, Shuwei

    2018-02-01

    Inland aquaculture ponds have been documented as important sources of atmospheric methane (CH4) and nitrous oxide (N2O), while their regional or global source strength remains unclear due to lack of direct flux measurements by covering more typical habitat-specific aquaculture environments. In this study, we compared the CH4 and N2O fluxes from rice paddies and nearby inland fish aquaculture wetlands that were converted from rice paddies in southeast China. Both CH4 and N2O fluxes were positively related to water temperature and sediment dissolved organic carbon, but negatively related to water dissolved oxygen concentration. More robust response of N2O fluxes to water mineral N was observed than to sediment mineral N. Annual CH4 and N2O fluxes from inland fish aquaculture averaged 0.51 mg m-2 h-1 and 54.78 μg m-2 h-1, amounting to 42.31 kg CH4 ha-1 and 2.99 kg N2O-N ha-1, respectively. The conversion of rice paddies to conventional fish aquaculture significantly reduced CH4 and N2O emissions by 23% and 66%, respectively. The emission factor for N2O was estimated to be 0.46% of total N input in the feed or 1.23 g N2O-N kg-1 aquaculture production. The estimate of sustained-flux global warming potential of annual CH4 and N2O emissions and the net economic profit suggested that such conversion of rice paddies to inland fish aquaculture would help to reconcile the dilemma for simultaneously achieving both low climatic impacts and high economic benefits in China. More solid direct field measurements from inland aquaculture are in urgent need to direct the overall budget of national or global CH4 and N2O fluxes.

  8. Integrated thermal control and system assessment in plug-chip spray cooling enclosure

    International Nuclear Information System (INIS)

    Zhang, Wei-Wei; Cheng, Wen-Long; Shao, Shi-Dong; Jiang, Li-Jia; Hong, Da-Liang

    2016-01-01

    Highlights: • A novel multi-heat source plug-chip spray cooling enclosure was designed. • Enhanced surfaces with different geometric were analyzed in integrated enclosure. • Overall thermal control with adjustable parameters in enclosure was studied. • Temperature disequilibrium of multi-heat source in enclosure was tested. • A comprehensive assessment system used to evaluate the practicality was proposed. - Abstract: Practical and integrated spray cooling system is urgently needed for the cooling of high-performance electronic chips due to the growth requirements of thermal management in workstation. The integration of multi heat sources and the management of integral system are particularly lacking. In order to fill the vacancies in the study of plug-chip spray cooling, an integrated cooling enclosure was designed in this paper. Multi heat sources were placed in sealed space and the heat was removed by spray. The printed circuit board plug-ins and radio frequency resistors were used as analog motherboards and chips, respectively. The enhanced surfaces with four different geometries and the plain surface were studied under the conditions of different inclination angles. The results were compared and the maximum critical heat flux (CHF) was obtained. Moreover, with the intention of the overall management of multi-heat source in integrated enclosure, the effect of the flow rate and the temperature disequilibrium, and the pulse heating in the process of transient cooling were also analyzed. In addition, a comprehensive assessment system, used to evaluate the practicality of spray cooling experimental devices, was proposed and the performance of enclosure was evaluated.

  9. The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study

    Directory of Open Access Journals (Sweden)

    Serbulov Alexey

    2012-03-01

    Full Text Available 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 Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

  10. 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.

  11. Manual on shielded enclosures. Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1992-01-01

    This booklet contains a basic guide to the principles of the production of ionizing radiation and to methods of radiation protection and dosimetry, and a discussion of the need for shielded enclosures. Shielding materials and the design of the enclosures are described

  12. [Microbial community in nitrogen cycle of aquaculture water of the Pearl River Delta].

    Science.gov (United States)

    Cai, Xiaolong; Luo, Jianfei; Lin, Weitie; Tian, Guoliang

    2012-05-04

    In order to study the characteristic of nitrogen transport, the community structure and diversity of related microorganisms in aquaculture water of the Pearl River Delta. We established an artificial aquaculture ecosystem to study the microbial community of 15N-stable isotope probing (15N-SIP) labeled nitrogen transport microorganisms. The 15N-labeled DNA was separated by CsCl-ethidium bromide density gradient centrifugation, and was used to construct 16S rRNA gene clone libraries of bacteria and archaea. Phylogenetic analysis shows that 19 Operational Taxonomic Units (OTUs) from bacterial library were clustered in Proteobacteria and Planctomycetes. Proteobacteria (99.2%) was the dominant group, mainly consisted of Comamonas (15.7%), Nitrosomonas (12.4%), Enterobacteriaceae (11.5%) and Nitrobacter (11.5%). From archaeal library 9 OTUs were divided into 3 phyla: Thaumarchaeota, Crenarchaeota and Euryarchaeota. We successfully elucidated the microbial community of nitrogen transport microorganisms in aquaculture water of Pearl River Delta by using 15N-SIP. The data of the community will provide essential information for isolating nitrogen degrading microorganism, and provide scientific basis for creating a healthy aquaculture environment.

  13. Lessons from two high CO2 worlds - future oceans and intensive aquaculture.

    Science.gov (United States)

    Ellis, Robert P; Urbina, Mauricio A; Wilson, Rod W

    2017-06-01

    Exponentially rising CO 2 (currently ~400 μatm) is driving climate change and causing acidification of both marine and freshwater environments. Physiologists have long known that CO 2 directly affects acid-base and ion regulation, respiratory function and aerobic performance in aquatic animals. More recently, many studies have demonstrated that elevated CO 2 projected for end of this century (e.g. 800-1000 μatm) can also impact physiology, and have substantial effects on behaviours linked to sensory stimuli (smell, hearing and vision) both having negative implications for fitness and survival. In contrast, the aquaculture industry was farming aquatic animals at CO 2 levels that far exceed end-of-century climate change projections (sometimes >10 000 μatm) long before the term 'ocean acidification' was coined, with limited detrimental effects reported. It is therefore vital to understand the reasons behind this apparent discrepancy. Potential explanations include 1) the use of 'control' CO 2 levels in aquaculture studies that go beyond 2100 projections in an ocean acidification context; 2) the relatively benign environment in aquaculture (abundant food, disease protection, absence of predators) compared to the wild; 3) aquaculture species having been chosen due to their natural tolerance to the intensive conditions, including CO 2 levels; or 4) the breeding of species within intensive aquaculture having further selected traits that confer tolerance to elevated CO 2 . We highlight this issue and outline the insights that climate change and aquaculture science can offer for both marine and freshwater settings. Integrating these two fields will stimulate discussion on the direction of future cross-disciplinary research. In doing so, this article aimed to optimize future research efforts and elucidate effective mitigation strategies for managing the negative impacts of elevated CO 2 on future aquatic ecosystems and the sustainability of fish and shellfish

  14. Aquaculture Thesaurus: Descriptors Used in the National Aquaculture Information System.

    Science.gov (United States)

    Lanier, James A.; And Others

    This document provides a listing of descriptors used in the National Aquaculture Information System (NAIS), a computer information storage and retrieval system on marine, brackish, and freshwater organisms. Included are an explanation of how to use the document, subject index terms, and a brief bibliography of the literature used in developing the…

  15. Humidity Buildup in Electronic Enclosures Exposed to Constant Conditions

    DEFF Research Database (Denmark)

    Conseil, Helene; Staliulionis, Zygimantas; Jellesen, Morten Stendahl

    2017-01-01

    Electronic components and devices are exposed to a wide variety of climatic conditions, therefore the protection of electronic devices from humidity is becoming a critical factor in the system design. The ingress of moisture into typical electronic enclosures has been studied with defined paramet....... The moisture buildup inside the enclosure has been simulated using an equivalent RC circuit consisting of variables like controlled resistors and capacitors to describe the diffusivity, permeability, and storage in polymers....

  16. 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.

  17. Aquaculture in mangrove environment

    Digital Repository Service at National Institute of Oceanography (India)

    Parulekar, A.H.

    vegetation forms an integral part of most productive and presently underutilised coastal ecosystem. It needs to be used in controlled manner. This would offer immense opportunities for generating food resources through aquaculture...

  18. Possibilities for marker-assisted selection in aquaculture breeding schemes

    International Nuclear Information System (INIS)

    Sonesson, A.K.

    2007-01-01

    FAO estimates that there are around 200 species in aquaculture. However, only a few species have ongoing selective breeding programmes. Marker-assisted selection (MAS) is not used in any aquaculture breeding scheme today. The aim of this chapter, therefore, is to review briefly the current status of aquaculture breeding schemes and to evaluate the possibilities for MAS of aquaculture species. Genetic marker maps have been published for some species in culture. The marker density of these maps is, in general, rather low and the maps are composed of many amplified fragment length polymorphism (AFLP) markers anchored to few microsatellites. Some quantitative trait loci (QTL) have been identified for economically important traits, but they are not yet mapped at a high density. Computer simulations of within-family MAS schemes show a very high increase in genetic gain compared with conventional family-based breeding schemes, mainly due to the large family sizes that are typical for aquaculture breeding schemes. The use of genetic markers to identify individuals and their implications for breeding schemes with control of inbreeding are discussed. (author)

  19. Towards sustainable coexistence of aquaculture and fisheries in the coastal zone

    DEFF Research Database (Denmark)

    Bergh, Øjvind; Gomez, Emma Bello; Børsheim, Knut Yngve

    2012-01-01

    Globally, coastal areas are subject to an increase in competing activities. Coastal fisheries and aquaculture are highly dependent on availability and accessibility of appropriate sites. Aquaculture production is increasing, whereas fisheries are at best stagnant. Coastal activities also include ......, both industries represent human activities strongly influencing, and influenced by, the environment. Management of aquaculture and fisheries, as well as other uses of the coastal zone, should be considered integral parts with local variations in their respective importance.......Globally, coastal areas are subject to an increase in competing activities. Coastal fisheries and aquaculture are highly dependent on availability and accessibility of appropriate sites. Aquaculture production is increasing, whereas fisheries are at best stagnant. Coastal activities also include...

  20. Antibiotic Resistance of Diverse Bacteria from Aquaculture in Borneo

    Directory of Open Access Journals (Sweden)

    M. M. Kathleen

    2016-01-01

    Full Text Available The administration of antimicrobials in aquaculture provides a selective pressure creating a reservoir of multiple resistant bacteria in the cultured fish and shrimps as well as the aquaculture environment. The objective of this study was to determine the extent of antibiotic resistance in aquaculture products and aquaculture’s surrounding environment in Sarawak, Malaysian Borneo. Ninety-four identified bacterial isolates constituted of 17 genera were isolated from sediment, water, and cultured organisms (fish and shrimp in selected aquaculture farms. These isolates were tested for their antibiotic resistance against 22 antibiotics from several groups using the disk diffusion method. The results show that the highest resistance was observed towards streptomycin (85%, n=20, while the lowest resistance was towards gentamicin (1.1%, n=90. The multiple antibiotic resistant (MAR index of the isolates tested ranged between 0 and 0.63. It was suggested that isolates with MAR index > 0.2 were recovered from sources with high risk of antibiotic resistant contamination. This study revealed low level of antibiotic resistance in the aquaculture bacterial isolates except for streptomycin and ampicillin (>50% resistance, n=94 which have been used in the aquaculture industry for several decades. Antibiotic resistant patterns should be continuously monitored to predict the emergence and widespread of MAR. Effective action is needed to keep the new resistance from further developing and spreading.

  1. Japanese aquaculture with thermal water from power plants

    International Nuclear Information System (INIS)

    Kuroda, T.

    1977-01-01

    The present level of thermal aquaculture, utilizing thermal water which is waste cooling water from nuclear power plant, in Japan is reported. There are 13 major potential areas for thermal aquaculture in cooperation with conventional type thermal power plants, seven of which are actually operating. Aquaculture facilities of all these are on land, none in the sea. Of these seven centers, those that have already commercialized their nursery methods or are approaching that stage of research and development, are Tohoku Hatsuden Kogyo Ltd., Tsuruga Hama Land Ltd. and Kyushu Rinsan Ltd. Major problems faced specialists in Japanese thermal aquaculture are water temperature, water quality, radioactivity and costs. For keeping the water temperature constant all seasons, cooling or heating by natural sea water may be used. Even negligible amounts of radioactivity that nuclear power plants release into the sea will concentrate in the systems of marine life. A strict precautionary checking routine is used to detect radioactivity in marine life. (Kobatake, H.)

  2. Can greening of aquaculture sequester blue carbon?

    Science.gov (United States)

    Ahmed, Nesar; Bunting, Stuart W; Glaser, Marion; Flaherty, Mark S; Diana, James S

    2017-05-01

    Globally, blue carbon (i.e., carbon in coastal and marine ecosystems) emissions have been seriously augmented due to the devastating effects of anthropogenic pressures on coastal ecosystems including mangrove swamps, salt marshes, and seagrass meadows. The greening of aquaculture, however, including an ecosystem approach to Integrated Aquaculture-Agriculture (IAA) and Integrated Multi-Trophic Aquaculture (IMTA) could play a significant role in reversing this trend, enhancing coastal ecosystems, and sequestering blue carbon. Ponds within IAA farming systems sequester more carbon per unit area than conventional fish ponds, natural lakes, and inland seas. The translocation of shrimp culture from mangrove swamps to offshore IMTA could reduce mangrove loss, reverse blue carbon emissions, and in turn increase storage of blue carbon through restoration of mangroves. Moreover, offshore IMTA may create a barrier to trawl fishing which in turn could help restore seagrasses and further enhance blue carbon sequestration. Seaweed and shellfish culture within IMTA could also help to sequester more blue carbon. The greening of aquaculture could face several challenges that need to be addressed in order to realize substantial benefits from enhanced blue carbon sequestration and eventually contribute to global climate change mitigation.

  3. Oxygen ingress study of 3D printed gaseous radiation detector enclosures

    Energy Technology Data Exchange (ETDEWEB)

    Steer, Christopher A.; Durose, Aaron [AWE, Alderrnaston, Reading, Berkshire, RG7 4PR (United Kingdom)

    2015-07-01

    As part of our ongoing studies into the potential application of 3D printing techniques to gaseous radiation detectors, we have studied the ability of 3D printed enclosures to resist environmental oxygen ingress. A set of cuboid and hexagonal prism shaped enclosures with wall thicknesses of 4 mm, 6 mm, 8 mm and 10 mm were designed and printed in nylon using a EOSINT P 730 Selective Laser Sintering 3D printer system These test enclosures provide a comparison of different environmental gas ingress for different 3D printing techniques. The rate of change of oxygen concentration was found to be linear, decreasing as the wall thickness increases. It was also found that the hexagonal prism geometry produced a lower rate of change of oxygen concentration compared with the cuboid shaped enclosures. Possible reasons as to why these results were obtained are discussed The implications for the this study for deployable systems are also discussed (authors)

  4. Oxygen ingress study of 3D printed gaseous radiation detector enclosures

    International Nuclear Information System (INIS)

    Steer, Christopher A.; Durose, Aaron

    2015-01-01

    As part of our ongoing studies into the potential application of 3D printing techniques to gaseous radiation detectors, we have studied the ability of 3D printed enclosures to resist environmental oxygen ingress. A set of cuboid and hexagonal prism shaped enclosures with wall thicknesses of 4 mm, 6 mm, 8 mm and 10 mm were designed and printed in nylon using a EOSINT P 730 Selective Laser Sintering 3D printer system These test enclosures provide a comparison of different environmental gas ingress for different 3D printing techniques. The rate of change of oxygen concentration was found to be linear, decreasing as the wall thickness increases. It was also found that the hexagonal prism geometry produced a lower rate of change of oxygen concentration compared with the cuboid shaped enclosures. Possible reasons as to why these results were obtained are discussed The implications for the this study for deployable systems are also discussed (authors)

  5. Numerical analysis of a heat-generating, truncated conical porous bed in a fluid-filled enclosure

    International Nuclear Information System (INIS)

    Chakravarty, Aranyak; Datta, Priyankan; Ghosh, Koushik; Sen, Swarnendu; Mukhopadhyay, Achintya

    2016-01-01

    Analysis of natural convection in enclosures containing heat generating porous medium has important applications related to geothermal, chemical, thermal and nuclear energy such as in-vessel cooling of debris beds in nuclear reactors, cooling of coal stockpiles etc. The objective of the present numerical study is to characterise the pattern of fluid flow and energy transfer during steady laminar natural convective flow in a cylindrical enclosure with a centrally placed heat generating porous bed. Flow through porous region is modelled using Darcy–Brinkmann–Forchheimer model and local thermal equilibrium is assumed for the porous region. Analysis is carried out for a wide range of Rayleigh number (Ra), Darcy number (Da) and thermal conductivity ratio, as well as for different bed geometries. It is observed that in addition to Ra and Da, the bed geometry also plays a very important role in determining flow field and temperature distribution within the enclosure. Interestingly, a significant change is observed in energy transfer mode from the porous bed corresponding to specific values of bed permeability and bed heat generation rate. This is characterised in terms of Ra and Da. Further, it is observed that this change in energy transfer mode is highly dependent on Ra. - Highlights: • Natural convection is analysed in an enclosure with a heat generating porous bed. • Effect of dimensionless parameters as well as bed geometry has been investigated. • Energy transfer mechanism from porous bed changes with dimensionless parameters. • Bed geometry significantly affects fluid flow and energy transfer in the enclosure.

  6. 55-68 Impact of Area Enclosures on Density and Diversity of Large ...

    African Journals Online (AJOL)

    1Department of Land Resources Management and Environmental Protection, Mekelle University, ... The enclosures have higher density and diversity of large wild mammals ..... in it. Figure 4 Human interference in enclosures of the study area ...

  7. Design, construction and testing of a DC bioeffects test enclosure for small animals. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, M J; Preache, M M

    1980-11-01

    This final report describes both the engineering development of a DC bioeffects test enclosure for small laboratory animals, and the biological protocol for the use of such enclosures in the testing of animals to determine possible biological effects of the environment associated with HVDC transmission lines. The test enclosure which has been designed is a modular unit, which will house up to eight rat-sized animals in individual compartments. Multiple test enclosures can be used to test larger numbers of animals. A prototype test enclosure has been fabricated and tested to characterize its electrical performance characteristics. The test enclosure provides a simulation of the dominant environment associated with HVDC transmission lines; namely, a static electric field and an ion current density. A biological experimental design has been developed for assessing the effects of the dominant components of the HVDC transmission line environment.

  8. Nutrient removal from Chinese coastal waters by large-scale seaweed aquaculture

    KAUST Repository

    Xiao, Xi

    2017-04-21

    China is facing intense coastal eutrophication. Large-scale seaweed aquaculture in China is popular, now accounting for over 2/3\\'s of global production. Here, we estimate the nutrient removal capability of large-scale Chinese seaweed farms to determine its significance in mitigating eutrophication. We combined estimates of yield and nutrient concentration of Chinese seaweed aquaculture to quantify that one hectare of seaweed aquaculture removes the equivalent nutrient inputs entering 17.8 ha for nitrogen and 126.7 ha for phosphorus of Chinese coastal waters, respectively. Chinese seaweed aquaculture annually removes approximately 75,000 t nitrogen and 9,500 t phosphorus. Whereas removal of the total N inputs to Chinese coastal waters requires a seaweed farming area 17 times larger than the extant area, one and a half times more of the seaweed area would be able to remove close to 100% of the P inputs. With the current growth rate of seaweed aquaculture, we project this industry will remove 100% of the current phosphorus inputs to Chinese coastal waters by 2026. Hence, seaweed aquaculture already plays a hitherto unrealized role in mitigating coastal eutrophication, a role that may be greatly expanded with future growth of seaweed aquaculture.

  9. Nutrient removal from Chinese coastal waters by large-scale seaweed aquaculture

    KAUST Repository

    Xiao, Xi; Agusti, Susana; Lin, Fang; Li, Ke; Pan, Yaoru; Yu, Yan; Zheng, Yuhan; Wu, Jiaping; Duarte, Carlos M.

    2017-01-01

    China is facing intense coastal eutrophication. Large-scale seaweed aquaculture in China is popular, now accounting for over 2/3's of global production. Here, we estimate the nutrient removal capability of large-scale Chinese seaweed farms to determine its significance in mitigating eutrophication. We combined estimates of yield and nutrient concentration of Chinese seaweed aquaculture to quantify that one hectare of seaweed aquaculture removes the equivalent nutrient inputs entering 17.8 ha for nitrogen and 126.7 ha for phosphorus of Chinese coastal waters, respectively. Chinese seaweed aquaculture annually removes approximately 75,000 t nitrogen and 9,500 t phosphorus. Whereas removal of the total N inputs to Chinese coastal waters requires a seaweed farming area 17 times larger than the extant area, one and a half times more of the seaweed area would be able to remove close to 100% of the P inputs. With the current growth rate of seaweed aquaculture, we project this industry will remove 100% of the current phosphorus inputs to Chinese coastal waters by 2026. Hence, seaweed aquaculture already plays a hitherto unrealized role in mitigating coastal eutrophication, a role that may be greatly expanded with future growth of seaweed aquaculture.

  10. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed by...

  11. 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

  12. Aquaculture. Teacher Edition.

    Science.gov (United States)

    Walker, Susan S.

    This color-coded guide was developed to assist teachers in helping interested students plan, build, stock, and run aquaculture facilities of varied sizes. The guide contains 15 instructional units, each of which includes some or all of the following basic components: objective sheet, suggested activities for the teacher, instructor supplements,…

  13. Aquaculture Asia, Vol. 7, No. 3, pp.1-60, July - September 2002

    OpenAIRE

    2002-01-01

    CONTENTS: Sustainable Aquaculture - Peter Edwards writes on rural aquaculture: Aquaculture for Poverty Alleviation and Food Security - Part II. Shrimp pond waste management by U Win Latt. The role of rural extension in the sustainable development of Chinese aquaculture by Min Kuanhong. Farmers as Scientists: Diversity enhances profitability and sustainability by M.C. Nandeesha. Properties of Liming Materials by Claude E. Boyd, Mali Boonyaratpalin & Taworn Thunjai. Seed Produc...

  14. Major constraints affecting aquaculture development in Akwa Ibom ...

    African Journals Online (AJOL)

    The study contributes to nationwide attempts to enhance the contributions of aquaculture to the fishery subsector, and consequent overall gross domestic product of Nigeria, as well as to the protein intake of her citizenry. The focus is on the determination of the magnitude of constraints affecting aquaculture development in ...

  15. Key Performance Characteristics of Organic Shrimp Aquaculture in Southwest Bangladesh

    Directory of Open Access Journals (Sweden)

    Christian Reinhard Vogl

    2012-05-01

    Full Text Available In Bangladesh, black tiger shrimp (Penaeus monodon; Fabricius, 1798 aquaculture has come to be one of the most important sectors in both the rural and national economies. Likewise, organic shrimp aquaculture has emerged as an alternative farming enterprise for farmers especially in the southwestern districts of Bangladesh. The present study aims to show key performance characteristics of organic shrimp farmers and farming in a prototypical shrimp farming area in Bangladesh. Data was collected in 2009 from organic shrimp farmers in the Kaligonj and Shyamnagar sub-districts through questionnaire interviews, transect walks and focus group discussions. The mean productivity of organic shrimp farming in the area is 320 kg ha−1 yr−1 (ranging from 120 to 711 kg ha−1year−1. Organic farmers are more likely to have a higher monthly income and less aquaculture experience. Moreover, suitable landholdings and classified labor distribution have been found to play an important role in the development of organic shrimp aquaculture. The most common assets of organic shrimp aquaculture are high yield, low production cost, available post larvae and high market prices. Small business farmers are likely to earn more income benefits from organic shrimp aquaculture than their larger-scale counterparts. Finally, the paper suggests that more research is needed to stimulate the success of organic shrimp aquaculture.

  16. Investigations into the dynamics of aerosols in enclosures as used for air pollution studies

    International Nuclear Information System (INIS)

    Vate, J.F. van de.

    1980-07-01

    The author treats aerosol behaviour under various conditions in enclosed spaces. A model is given describing aerosol removal from enclosed spaces; boundary conditions are given for non-stirred deposition of aerosols by sedimentation and diffusion. Experimental results are presented for unheated dry enclosures, heated dry enclosures, enclosures with a heated pool of liquid, and smog chambers. (G.T.H.)

  17. Sécurité alimentaire, pêches et aquaculture en Amazonie bolivienne ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-03-01

    Food security, fisheries and aquaculture in the Bolivian Amazon : final technical report (March 1, 2011 to February 28, 2014). Download PDF. Briefs. Pêches, aquaculture et bien vivre en Bolivie : contributions à la sécurité alimentaire. Download PDF. Briefs. Fisheries, aquaculture and living well in Bolivia : contributions to ...

  18. Nest establishment, pollination efficiency, and reproductive success of Megachile rotundata (Hymenoptera: Megachilidae) in relation to resource availability in field enclosures.

    Science.gov (United States)

    Pitts-Singer, Theresa L; Bosch, Jordi

    2010-02-01

    The alfalfa leafcutting bee, Megachile rotundata (Fabricius), is used to pollinate alfalfa, Medicago sativa L., for seed production in the United States and Canada. It is difficult to reliably sustain commercial M. rotundata populations in the United States because of problems with disease, parasites, predators, and unexplained mortality. One possible explanation for early immature mortality is that, relative to floral availability, superfluous numbers of bees are released in alfalfa fields where resources quickly become limited. Our objective was to determine how M. rotundata density affects bee nesting, pollination efficiency, and reproductive success. Various numbers of bees were released into enclosures on an alfalfa field, but only 10-90% of released female bees established nests. Therefore, a "bee density index" was derived for each enclosure from the number of established females and number of open flowers over time. As the density index increased, significant reductions occurred in the number of pollinated flowers, number of nests, and number of cells produced per bee, as well as the percentage of cells that produced viable prepupae by summer's end and the percentage that produced adult bees. The percentage of cells resulting in early brood mortality (i.e., pollen balls) significantly increased as the density index increased. We conclude that bee nest establishment, pollination efficiency, and reproductive success are compromised when bee densities are high relative to floral resource availability. Open field studies are needed to determine commercial bee densities that result in sustainable bee populations and adequate pollination for profitable alfalfa seed production.

  19. Aqua-Topics. Aquaculture for Youth and Youth Educators.

    Science.gov (United States)

    McVey, Eileen

    This booklet contains information on aquaculture and ideas for aquaculture projects. The information provided is for students at upper elementary through high school learning levels. Recommended activities at the end of the text are organized by level of difficulty. The activities can be modified depending on area and availability of resources. A…

  20. Enclosure design for flock-level, chronic exposure of birds to air contaminant mixtures.

    Science.gov (United States)

    North, Michelle A; Kinniburgh, David W; Smits, Judit E G

    2018-05-01

    The objective of this study was to design an enclosure suitable for studying the ecotoxicological effects of vehicle emissions on groups of wild birds without compromising welfare. Two, adjacent enclosures sheltered from sunlight, wind and rain, were bird-proofed and wrapped with thick polyethylene sheeting. Emissions were directed into the treatment enclosure from the exhaust of a light-duty gasoline truck, using flexible, heat-proof pipe, with joins sealed to prevent leakage. During active exposure, the engine was idled for 5 h/day, 6 days/week for 4 weeks. Fans maintained positive pressure (controls) and negative pressure (treatment), preventing cross-contamination of enclosures and protecting investigators. Four sets of passive, badge-type samplers were distributed across each enclosure, measuring nitrogen dioxide, sulfur dioxide and volatile organic compounds (NO 2 , SO 2 and VOCs, respectively), and were complemented by active monitors measuring VOCs and particulate matter (2.5 µm diameter, PM 2.5 ). We found that the concentrations of NO 2 , SO 2 and PM 2.5 were not different between treatment and control enclosures. Volatile organic compounds (e.g. benzene, toluene, ethylbenzene and xylenes) were approximately six times higher in the treatment enclosure than control (13.23 and 2.13 µg m -1 , respectively). In conclusion, this represents a successful, practical design for studying the effects of sub-chronic to chronic exposure to realistic mixtures of vehicle exhaust contaminants, in groups of birds. Recommended modifications for future research include a chassis dynamometer (vehicle treadmill), to better replicate driving conditions including acceleration and deceleration.

  1. 50 CFR 14.161 - Primary enclosures.

    Science.gov (United States)

    2010-10-01

    ... Wild Mammals and Birds to the United States Specifications for Other Terrestrial Mammals § 14.161... primary enclosure shall provide adequate space for the animal to stand upright in a normal posture with... lie in a full prone position. Specifications for Birds ...

  2. Aerothermodynamic properties of stretched flames in enclosures

    Science.gov (United States)

    Rotman, D. A.; Oppenheim, A. K.

    Flames are stretched by being pulled along their frontal surface by the flow field in which they reside. Their trajectories tend to approach particle paths, acquiring eventually the role of contact boundaries, -interfaces between the burnt and unburnt medium that may broaden solely as a consequence of diffusion. Fundamental properties of flow fields governing such flames are determined here on the basis of the zero Mach number model, providng a rational method of approach to the computational analysis of combustion fields in enclosures where, besides the aerodynamic properties flow, the thermodynamic process of compression must be taken into account. To illustrate its application, the method is used to reveal the mechanism of formation of a tulip-shape flame in a rectangular enclosure under nonturbulent flow conditions.

  3. Freshwater Institute: Focused on improving recirculating aquaculture system technology

    Science.gov (United States)

    Recirculating aquaculture system (RAS) technologies help to overcome barriers to domestic aquaculture expansion and enhance the sustainability of the modern fish farming industry through reduction in environmental impacts. With RAS, fish farm expansion is no longer highly constrained by competition ...

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

    NARCIS (Netherlands)

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

    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

  5. Nutrient discharge from China’s aquaculture industry and associated environmental impacts

    Science.gov (United States)

    Zhang, Ying; Bleeker, Albert; Liu, Junguo

    2015-04-01

    China’s aquaculture industry accounts for the largest share of the world’s fishery production, and provides a principal source of protein for the nation’s booming population. However, the environmental effects of the nutrient loadings produced by this industry have not been systematically studied or reviewed. Few quantitative estimates exist for nutrient discharge from aquaculture and the resultant nutrient enrichment in waters and sediments. In this paper, we evaluate nutrient discharge from aquacultural systems into aquatic ecosystems and the resulting nutrient enrichment of water and sediments, based on data from 330 cases in 51 peer-reviewed publications. Nitrogen use efficiency ranged from 11.7% to 27.7%, whereas phosphorus use efficiency ranged from 8.7% to 21.2%. In 2010, aquacultural nutrient discharges into Chinese aquatic ecosystems included 1044 Gg total nitrogen (184 Gg N from mariculture; 860 Gg N freshwater culture) and 173 Gg total phosphorus (22 Gg P from mariculture; 151 Gg P from freshwater culture). Water bodies and sediments showed high levels of nutrient enrichment, especially in closed pond systems. However, this does not mean that open aquacultural systems have smaller nutrient losses. Improvement of feed efficiency in cage systems and retention of nutrients in closed systems will therefore be necessary. Strategies to increase nutrient recycling, such as integrated multi-trophic aquaculture, and social measures, such as subsidies, should be increased in the future. We recommend the recycling of nutrients in water and sediments by hybrid agricultural-aquacultural systems and the adoption of nutrient use efficiency as an indicator at farm or regional level for the sustainable development of aquaculture; such indicators; together with water quality indicators, can be used to guide evaluations of technological, policy, and economic approaches to improve the sustainability of Chinese aquaculture.

  6. Potential Impact of Mediterranean Aquaculture on the Wild Predatory Bluefish

    OpenAIRE

    Miralles, Laura; Mrugala, Agata; Sanchez-Jerez, Pablo; Juanes, Francis; Garcia-Vazquez, Eva

    2016-01-01

    Aquaculture impacts on wild populations of fish have been considered principally due to farm escapes. The Bluefish Pomatomus saltatrix, which exhibits two distinct genetic units in the Mediterranean Sea, is a voracious predator and is attracted to aquaculture cages to prey on farmed fish, particularly Gilthead Seabream Sparus aurata and European Sea Bass Dicentrarchus labrax. We compared the genetic diversity of adult Bluefish caught inside one aquaculture farm located in Spanish waters of th...

  7. Sécurité alimentaire, pêches et aquaculture en Amazonie bolivienne ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-03-01

    Food security, fisheries and aquaculture in the Bolivian Amazon : final technical report (March 1, 2011 to February 28, 2014). Téléchargez le PDF. Dossiers. Pêches, aquaculture et bien vivre en Bolivie : contributions à la sécurité alimentaire. Téléchargez le PDF. Dossiers. Fisheries, aquaculture and living well in Bolivia ...

  8. Constructal design of phase change material enclosures used for cooling electronic devices

    International Nuclear Information System (INIS)

    Kalbasi, Rasool; Salimpour, Mohammad Reza

    2015-01-01

    Recent developments in cooling methods for portable electronic devices have heightened the need for using the large latent heat capacity of phase change materials (PCM). The aim of the present study is to evaluate the thermal characteristics of a PCM-based heat sink with high conductive materials. The solution is acquired as a procession of optimization stages which starts with the elemental area and proceeds toward the first assembly. Every optimization stage is the result of maximizing the safe operation time without allowing the electronics to reach the critical temperature. Primarily, the degrees of freedom and constrains were defined and then by changing the geometrical parameters, the target function which is the maximization of operation time, was optimized. Results show that the melting process in rectangular enclosures with vertical fins attached to the heated bottom surface can be affected by the contact surface between the fin and PCM and the convection of the melted PCM. For a rectangular enclosure with a constant area, it is better to use wider enclosure than the square and thin one. Also results indicate that the ratio of the vertical fin thickness to the horizontal one does not have a considerable effect on performance. By increasing the number of enclosures, the contact surface is raised, but the performance is not necessarily improved. - Highlights: • Thermal characteristics of a finned PCM-based heat sink are studied. • Constructal theory was used to optimize the PCM enclosures. • By increasing the number of enclosures, the performance is not necessarily improved

  9. 9 CFR 3.6 - Primary enclosures.

    Science.gov (United States)

    2010-01-01

    ... coated with a material such as plastic or fiberglass. The suspended floor of any primary enclosure must... and behavioral characteristics, and in accordance with generally accepted husbandry practices. If the... characteristics, and in accordance with generally accepted husbandry practices as determined by the attending...

  10. 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.

  11. Counter-insurgents of the blue revolution? Parasites and diseases affecting aquaculture and science.

    Science.gov (United States)

    Blaylock, Reginald B; Bullard, Stephen A

    2014-12-01

    Aquaculture is the fastest-growing segment of food production and is expected to supply a growing portion of animal protein for consumption by humans. Because industrial aquaculture developed only recently compared to industrial agriculture, its development occurred within the context of a growing environmental awareness and acknowledgment of environmental issues associated with industrial farming. As such, parasites and diseases have become central criticisms of commercial aquaculture. This focus on parasites and diseases, however, has created a nexus of opportunities for research that has facilitated considerable scientific advances in the fields of parasitology and aquaculture. This paper reviews Myxobolus cerebralis , Lepeophtheirus salmonis , white spot syndrome virus, and assorted flatworms as select marquee aquaculture pathogens, summarizes the status of the diseases caused by each and their impacts on aquaculture, and highlights some of the significant contributions these pathogens have made to the science of parasitology and aquaculture.

  12. Optimizing Ocean Space: Co-siting Open Ocean Aquaculture

    Science.gov (United States)

    Cobb, B. L.; Wickliffe, L. C.; Morris, J. A., Jr.

    2016-12-01

    In January of 2016, NOAA's National Marine Fisheries Service released the Gulf Aquaculture Plan (GAP) to manage the development of environmentally sound and economically sustainable open ocean finfish aquaculture in the Gulf of Mexico (inside the U.S. Exclusive Economic Zone [EEZ]). The GAP provides the first regulatory framework for aquaculture in federal waters with estimated production of 64 million pounds of finfish, and an estimated economic impact of $264 million annually. The Gulf of Mexico is one of the most industrialized ocean basins in the world, with many existing ocean uses including oil and natural gas production, shipping and commerce, commercial fishing operations, and many protected areas to ensure conservation of valuable ecosystem resources and services. NOAA utilized spatial planning procedures and tools identifying suitable sites for establishing aquaculture through exclusion analyses using authoritative federal and state data housed in a centralized geodatabase. Through a highly collaborative, multi-agency effort a mock permitting exercise was conducted to illustrate the regulatory decision-making process for the Gulf. Further decision-making occurred through exploring co-siting opportunities with oil and natural gas platforms. Logistical co-siting was conducted to reduce overall operational costs by looking at distance to major port and commodity tonnage at each port. Importantly, the process of co-siting allows aquaculture to be coupled with other benefits, including the availability of previously established infrastructure and the reduction of environmental impacts.

  13. Numerical simulation of transient moisture transfer into an electronic enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Nasirabadi, P. Shojaee; Jabbari, M.; Hattel, J. H. [Process Modelling Group, Department of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, 2800 Kgs. Lyngby (Denmark)

    2016-06-08

    Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisture transfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermal stresses. It is therefore essential to study the local climate inside the enclosures to be able to protect the electronic systems. In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce the CPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which the real 3D geometry is approximated by a 2D axial symmetry one. The results for 2D and 3D models were compared in order to calibrate the 2D representation. Furthermore, simulation results were compared with experimental data and good agreement was found.

  14. Numerical simulation of transient moisture transfer into an electronic enclosure

    International Nuclear Information System (INIS)

    Nasirabadi, P. Shojaee; Jabbari, M.; Hattel, J. H.

    2016-01-01

    Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisture transfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermal stresses. It is therefore essential to study the local climate inside the enclosures to be able to protect the electronic systems. In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce the CPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which the real 3D geometry is approximated by a 2D axial symmetry one. The results for 2D and 3D models were compared in order to calibrate the 2D representation. Furthermore, simulation results were compared with experimental data and good agreement was found.

  15. 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, Åsa; Kautsky, Nils; Levin, Simon A.; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H.; Xepapadeas, Tasos; de Zeeuw, Aart

    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 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

  16. Laying hen movement in a commercial aviary: Enclosure to floor and back again.

    Science.gov (United States)

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    Many producers in the laying hen industry, including in North America, are phasing out conventional cages in response to consumer demands and sometimes subsequent legislation. Alternative housing systems such as aviaries are being implemented in an attempt to improve hen welfare. Aviaries provide additional space and resources to groups of hens, including a litter area on the floor. However, little is known about hen movement between tiered enclosures and floor litter areas in aviary systems. Diurnal rhythms and social attraction may result in peak times of movement that could lead to overcrowding of areas, or alternatively hen preferences may lead to some areas not being fully utilized. We monitored hen movement between tiered enclosures and litter areas, including movement on and off the outer perch, across the day at peak, mid and end of lay in a commercial aviary. Hens moved onto and off of the open litter area across the day, transitioning between tiered enclosures, outer perches, open litter areas, and litter areas under tiered enclosures. At certain times of day, there were periods of greater hen movement down to the open litter area and between litter areas. For example, more hens were typically observed exiting enclosures, jumping from perches to open litter, and traveling between open litter and litter under tiered enclosures in the morning (all P ≤ 0.001). In all but one instance, more hens were observed on open litter areas in the afternoon than at other times of day (all P ≤ 0.029). However, hen re-entry to tiered enclosures showed less circadian patterning. Hen movement was observed between areas of interest at all sampled time periods, indicating hens use all areas of the system. Further research should examine whether all individual hens do move between areas equally, including within levels of the tiered enclosure, or if crowding occurs on the outer perches or in the litter during times of peak movement. © 2015 Poultry Science Association Inc.

  17. Feed conversion efficiency in aquaculture: do we measure it correctly?

    Science.gov (United States)

    Fry, Jillian P.; Mailloux, Nicholas A.; Love, David C.; Milli, Michael C.; Cao, Ling

    2018-02-01

    Globally, demand for food animal products is rising. At the same time, we face mounting, related pressures including limited natural resources, negative environmental externalities, climate disruption, and population growth. Governments and other stakeholders are seeking strategies to boost food production efficiency and food system resiliency, and aquaculture (farmed seafood) is commonly viewed as having a major role in improving global food security based on longstanding measures of animal production efficiency. The most widely used measurement is called the ‘feed conversion ratio’ (FCR), which is the weight of feed administered over the lifetime of an animal divided by weight gained. By this measure, fed aquaculture and chickens are similarly efficient at converting feed into animal biomass, and both are more efficient compared to pigs and cattle. FCR does not account for differences in feed content, edible portion of an animal, or nutritional quality of the final product. Given these limitations, we searched the literature for alternative efficiency measures and identified ‘nutrient retention’, which can be used to compare protein and calories in feed (inputs) and edible portions of animals (outputs). Protein and calorie retention have not been calculated for most aquaculture species. Focusing on commercial production, we collected data on feed composition, feed conversion ratios, edible portions (i.e. yield), and nutritional content of edible flesh for nine aquatic and three terrestrial farmed animal species. We estimate that 19% of protein and 10% of calories in feed for aquatic species are ultimately made available in the human food supply, with significant variation between species. Comparing all terrestrial and aquatic animals in the study, chickens are most efficient using these measures, followed by Atlantic salmon. Despite lower FCRs in aquaculture, protein and calorie retention for aquaculture production is comparable to livestock production

  18. Potential hazards and risks associated with the aquaculture industry ...

    African Journals Online (AJOL)

    Aquaculture, the farming of aquatic organisms, is fraught with potential hazards and risks which are categorized into occupational, environmental, food safety and public health. This paper reviewed major hazards and risks associated with the aquaculture industry and proffered strategies for their management and control.

  19. The growth of finfish in global open-ocean aquaculture under climate change.

    Science.gov (United States)

    Klinger, Dane H; Levin, Simon A; Watson, James R

    2017-10-11

    Aquaculture production is projected to expand from land-based operations to the open ocean as demand for seafood grows and competition increases for inputs to land-based aquaculture, such as freshwater and suitable land. In contrast to land-based production, open-ocean aquaculture is constrained by oceanographic factors, such as current speeds and seawater temperature, which are dynamic in time and space, and cannot easily be controlled. As such, the potential for offshore aquaculture to increase seafood production is tied to the physical state of the oceans. We employ a novel spatial model to estimate the potential of open-ocean finfish aquaculture globally, given physical, biological and technological constraints. Finfish growth potential for three common aquaculture species representing different thermal guilds-Atlantic salmon ( Salmo salar ), gilthead seabream ( Sparus aurata ) and cobia ( Rachycentron canadum )-is compared across species and regions and with climate change, based on outputs of a high-resolution global climate model. Globally, there are ample areas that are physically suitable for fish growth and potential expansion of the nascent aquaculture industry. The effects of climate change are heterogeneous across species and regions, but areas with existing aquaculture industries are likely to see increases in growth rates. In areas where climate change results in reduced growth rates, adaptation measures, such as selective breeding, can probably offset potential production losses. © 2017 The Author(s).

  20. Turbulence modeling of natural convection in enclosures: A review

    International Nuclear Information System (INIS)

    Choi, Seok Ki; Kim, Seong O

    2012-01-01

    In this paper a review of recent developments of turbulence models for natural convection in enclosures is presented. The emphasis is placed on the effect of the treatments of Reynolds stress and turbulent heat flux on the stability and accuracy of the solution for natural convection in enclosures. The turbulence models considered in the preset study are the two-layer k -ε model, the shear stress transport (SST) model, the elliptic-relaxation (V2-f) model and the elliptic-blending second-moment closure (EBM). Three different treatments of the turbulent heat flux are the generalized gradient diffusion hypothesis (GGDH), the algebraic flux model (AFM) and the differential flux model (DFM). The mathematical formulation of the above turbulence models and their solution method are presented. Evaluation of turbulence models are performed for turbulent natural convection in a 1:5 rectangular cavity ( Ra = 4.3x10 10 ) and in a square cavity with conducting top and bottom walls ( Ra =1.58x10 9 ) and the Rayleigh-Benard convection ( Ra = 2x10 6 ∼ Ra =10 9 ). The relative performances of turbulence models are examined and their successes and shortcomings are addressed

  1. Apparatus for posting materials into and out of enclosures

    International Nuclear Information System (INIS)

    Sperinck, W.A.; Ashcroft, K.C.

    1986-01-01

    The patent concerns an apparatus for posting toxic or radioactive materials into and out of a high integrity enclosure, such as a glovebox, through a port in a wall of the enclosure. The apparatus comprises a container for the materials, with a lid which is engageable with a door for the port, and the container is supported in a cradle. The door cannot be opened in the absence of a container in the cradle, and the container cannot be removed when the door and lid unit is away from the port. (UK)

  2. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    DEFF Research Database (Denmark)

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche

    2012-01-01

    for bivalve aquaculture be based on a tiered indicator monitoring system that is structured on the principle that increased environmental risk requires increased monitoring effort. More than 1 threshold for each indicator would permit implementation of predetermined impact prevention and mitigation measures......An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social...... and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–environment interactions and policy-related developments and decisions. The Drivers-Pressures-State Change-Impact-Response...

  3. Streptomyces bacteria as potential probiotics in aquaculture

    Directory of Open Access Journals (Sweden)

    Tan Loh eTeng Hern

    2016-02-01

    Full Text Available In response to the increased seafood demand from the ever-going human population, aquaculture has become the fastest growing animal food-producing sector. However, the indiscriminate use of antibiotics as a biological control agents for fish pathogens has led to the emergence of antibiotic resistance bacteria. Probiotics are defined as living microbial supplement that exert beneficial effects on hosts as well as improvement of environmental parameters. Probiotics have been proven to be effective in improving the growth, survival and health status of the aquatic livestock. This review aims to highlight the genus Streptomyces can be a good candidate for probiotics in aquaculture. Studies showed that the feed supplemented with Streptomyces could protect fish and shrimp from pathogens as well as increase the growth of the aquatic organisms. Furthermore, the limitations of Streptomyces as probiotics in aquaculture is also highlighted and solutions are discussed to these limitations.

  4. Genetically modified organisms (GMOs) and aquaculture.

    Science.gov (United States)

    Beardmore, J A; Porter, Joanne S

    2003-01-01

    This paper reviews the nature of genetically modified organisms (GMOs), the range of aquatic species in which GMOs have been produced, the methods and target genes employed, the benefits to aquaculture, the problems attached to use of GMOs in aquatic species and the regulatory and other social frameworks surrounding them. A set of recommendations aimed at best practice is appended. This states the potential value of GMOs in aquaculture but also calls for improved knowledge particularly of sites of integration, risk analysis, progress in achieving sterility in fish for production and better dissemination of relevant information.

  5. A GIS-based tool for an integrated assessment of spatial planning trade-offs with aquaculture.

    Science.gov (United States)

    Gimpel, Antje; Stelzenmüller, Vanessa; Töpsch, Sandra; Galparsoro, Ibon; Gubbins, Matthew; Miller, David; Murillas, Arantza; Murray, Alexander G; Pınarbaşı, Kemal; Roca, Guillem; Watret, Robert

    2018-06-15

    The increasing demand for protein from aquaculture will trigger a global expansion of the sector in coastal and offshore waters. While contributing to food security, potential conflicts with other traditional activities such as fisheries or tourism are inevitable, thus calling for decision-support tools to assess aquaculture planning scenarios in a multi-use context. Here we introduce the AquaSpace tool, one of the first Geographic Information System (GIS)-based planning tools empowering an integrated assessment and mapping of 30 indicators reflecting economic, environmental, inter-sectorial and socio-cultural risks and opportunities for proposed aquaculture systems in a marine environment. A bottom-up process consulting more than 350 stakeholders from 10 countries across southern and northern Europe enabled the direct consideration of stakeholder needs when developing the GIS AddIn. The AquaSpace tool is an open source product and builds in the prospective use of open source datasets at a European scale, hence aiming to improve reproducibility and collaboration in aquaculture science and research. Tool outputs comprise detailed reports and graphics allowing key stakeholders such as planners or licensing authorities to evaluate and communicate alternative planning scenarios and to take more informed decisions. With the help of the German North Sea case study we demonstrate here the tool application at multiple spatial scales with different aquaculture systems and under a range of space-related development constraints. The computation of these aquaculture planning scenarios and the assessment of their trade-offs showed that it is entirely possible to identify aquaculture sites, that correspondent to multifarious potential challenges, for instance by a low conflict potential, a low risk of disease spread, a comparable high economic profit and a low impact on touristic attractions. We believe that a transparent visualisation of risks and opportunities of aquaculture

  6. Current status of viral diseases in Indian shrimp aquaculture.

    Science.gov (United States)

    Tandel, G M; John, K Riji; Rosalind George, M; Prince Jeyaseelan, M J

    The intensification of aquaculture has been unique in showing the overwhelming changes in global food production in the last 100 years. Presently, it is playing a vital role in the economies of several countries. Conversely, it is also to be noted that the progression of aquaculture has been the foundation of anthropogenic alteration of a gigantic hierarchy and hence not astonishingly, it resulted in spread and emergence of an increasing group of new unknown diseases. In India, Penaeus monodon, black tiger shrimp was previously the foremost-cultivated shrimp species. Subsequently in 2008, the American white leg shrimp Litopenaeus vannamei has effectively replaced it. The change in dominant species has affected disease concerns in India as well as in world shrimp aquaculture. White spot syndrome virus (WSSV) is the most deleterious for both species. Hepatopancreatic parvovirus (HPV), Monodon baculovirus (MBV) and Infectious hypodermal and hematopoietic necrosis virus (IHHNV) are the other significant infectious agents of P. monodon and L. vannamei. An emerging disease of loose shell syndrome (LSS) was already reported from India during late 1998. A more recent disease of L. vannamei in India is monodon slow growth syndrome (MSGS), a component of which seems to be Laem-Singh virus (LSNV). Thus, most of the information in this review relates to new emerging pathogens that threaten the cultivation shrimp industry in India.

  7. Human Health Consequences of Use of Antimicrobial Agents in Aquaculture

    DEFF Research Database (Denmark)

    Heuer, Ole Eske; Kruse, H.; Grave, K.

    2009-01-01

    industry in many regions of the world and the widespread, intensive, and often unregulated use of antimicrobial agents in this area of animal production, efforts are needed to prevent development and spread of antimicrobial resistance in aquaculture to reduce the risk to human health....... in aquaculture, several are classified by the World Health Organisation as critically important for use in humans. Occurrence of resistance to these antimicrobial agents in human pathogens severely limits the therapeutic options in human infections. Considering the rapid growth and importance of aquaculture...... gene transfer and reach human pathogens, or drug-resistant pathogens from the aquatic environment may reach humans directly. Horizontal gene transfer may occur in the aquaculture environment, in the food chain, or in the human intestinal tract. Among the antimicrobial agents commonly used...

  8. 50 CFR 14.151 - Primary enclosures.

    Science.gov (United States)

    2010-10-01

    ... Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR TAKING... Wild Mammals and Birds to the United States Specifications for Sloths, Bats, and Flying Lemurs... located on the upper one-half of the primary enclosure. (b) No more than one sloth, bat, or flying lemur...

  9. Radiant cooling of an enclosure

    International Nuclear Information System (INIS)

    Chebihi, Abdeslam; Byun, Ki-Hong; Wen Jin; Smith, Theodore F.

    2006-01-01

    The purpose of this study is to analyze the potential for radiant cooling using the atmospheric sky window and to evaluate the desired characteristics of a radiant cooling material (RCM) applied to the ceiling window of a three-dimensional enclosure. The thermal characteristics of the system are governed by the geometry, ambient temperature, sky radiative temperature, amount of solar energy and its direction, heat transfer modes, wall radiative properties, and radiative properties of the RCMs. A semi-gray band analysis is utilized for the solar and infrared bands. The radiosity/irradiation method is used in each band to evaluate the radiant exchanges in the enclosure. The radiative properties for the RCM are varied in a parametric study to identify the desired properties of RCMs. For performance simulation of real RCMs, the radiative properties are calculated from spectral data. The desired solar property is a high reflectance for both opaque and semi-transparent RCMs. For a semi-transparent RCM, a low value of the solar transmittance is preferred. The desired infrared property is a high emittance for an opaque RCM. For a semi-transparent RCM, a high infrared transmittance is desired, and the emittance should be greater than zero

  10. Inland Aquaculture and Adaptation to Climate Change in Northern ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Documents. Modeling the effects of weather and climate on thermal stratification and the risks of low dissolved oxygen episodes in aquaculture ponds. Documents. Impacts of climate change and water uses on availability of water for aquaculture in the Lower Nan Basin. Documents. The role of middlemen networks and ...

  11. Enhancing Profitability of Pond Aquaculture in Ghana through Resource Management and Environmental Best Management Practices

    OpenAIRE

    Ansah, Yaw Boamah

    2014-01-01

    The accelerating pace of growth of aquaculture in sub-Saharan Africa has received much positive appraisal because of the potential of the industry to contribute to economic development and food security by providing jobs and animal protein. Adoption of best management practices (BMPs) holds the potential to ameliorate the related environmental impacts of aquaculture, such as in the amounts of nutrients and sediment that will enter natural water bodies from earthen pond effluents. The goals of...

  12. ZFS on RBODs - Leveraging RAID Controllers for Metrics and Enclosure Management

    Energy Technology Data Exchange (ETDEWEB)

    Stearman, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-03-30

    Traditionally, the Lustre file system has relied on the ldiskfs file system with reliable RAID (Redundant Array of Independent Disks) storage underneath. As of Lustre 2.4, ZFS was added as a backend file system, with built-in software RAID, thereby removing the need of expensive RAID controllers. ZFS was designed to work with JBOD (Just a Bunch Of Disks) storage enclosures under the Solaris Operating System, which provided a rich device management system. Long time users of the Lustre file system have relied on the RAID controllers to provide metrics and enclosure monitoring and management services, with rich APIs and command line interfaces. This paper will study a hybrid approach using an advanced full featured RAID enclosure which is presented to the host as a JBOD, This RBOD (RAIDed Bunch Of Disks) allows ZFS to do the RAID protection and error correction, while the RAID controller handles management of the disks and monitors the enclosure. It was hoped that the value of the RAID controller features would offset the additional cost, and that performance would not suffer in this mode. The test results revealed that the hybrid RBOD approach did suffer reduced performance.

  13. ZFS on RBODs - Leveraging RAID Controllers for Metrics and Enclosure Management

    International Nuclear Information System (INIS)

    Stearman, D. M.

    2015-01-01

    Traditionally, the Lustre file system has relied on the ldiskfs file system with reliable RAID (Redundant Array of Independent Disks) storage underneath. As of Lustre 2.4, ZFS was added as a backend file system, with built-in software RAID, thereby removing the need of expensive RAID controllers. ZFS was designed to work with JBOD (Just a Bunch Of Disks) storage enclosures under the Solaris Operating System, which provided a rich device management system. Long time users of the Lustre file system have relied on the RAID controllers to provide metrics and enclosure monitoring and management services, with rich APIs and command line interfaces. This paper will study a hybrid approach using an advanced full featured RAID enclosure which is presented to the host as a JBOD, This RBOD (RAIDed Bunch Of Disks) allows ZFS to do the RAID protection and error correction, while the RAID controller handles management of the disks and monitors the enclosure. It was hoped that the value of the RAID controller features would offset the additional cost, and that performance would not suffer in this mode. The test results revealed that the hybrid RBOD approach did suffer reduced performance.

  14. Impact of pond aquaculture effluents on seagrass performance in NE Hainan, tropical China

    International Nuclear Information System (INIS)

    Herbeck, Lucia S.; Sollich, Miriam; Unger, Daniela; Holmer, Marianne; Jennerjahn, Tim C.

    2014-01-01

    Highlights: • Seagrass performance in relation to large-scale pond aquaculture was assessed. • Effluent-affected seagrass meadows have a low biodiversity, shoot density and biomass. • Shading by epiphytes and sulphide poisoning are major decline mechanisms of seagrasses. • Distance to effluent source and pond agglomeration size are major determinants of seagrass degradation. - Abstract: The impact of pond aquaculture effluents on the distribution and performance of seagrasses was examined in NE Hainan, tropical China. Samples were taken along transects in three back-reef areas with different extent of aquaculture production in their hinterland. High δ 15 N in seagrass leaves and epiphytes (6–9‰) similar to values in pond effluents documented aquaculture as dominant nitrogen source in the back-reefs with decreasing impact with distance from shore. Seagrass species abundance, shoot density and biomass were lower and concentrations of nutrients, chlorophyll and suspended matter were higher at nearshore sites with high and moderate pond abundance than at the control site. High epiphyte loads and low δ 34 S in seagrass leaves suggest temporal shading and sulphide poisoning of the nearshore seagrasses. Observed gradients in environmental parameters and seagrass performance indicate that the distance from the pond outlets and size of the adjacent pond agglomeration are major determinants of seagrass degradation

  15. Effects of a new molt-inducing insecticide, tebufenozide, on zooplankton communities in lake enclosures.

    Science.gov (United States)

    Kreutzweiser, D P; Thomas, D R

    1995-10-01

    : A potent ecdysone agonist, tebufenozide, has recently been developed as a molt-inducing insecticide to control defoliating lepidopterans. As part of continuing research efforts to assess the effectiveness and environmental safety of this material for insect pest management in Canadian forests, tebufenozide (RH-5992-2F) was applied to large lake enclosures and the effects on zooplankton communities were evaluated. There were significant treatment effects at all test concentrations (0.07-0.66 mg L(-1) tebufenozide). Concentration-dependent reductions in the abundance of cladocerans indicated that there were direct toxic effects of tebufenozide on this group of macrozooplankton. There were no indications of direct toxic effects on copepods. Significant increases in abundance of rotifers in treated enclosures at the three higher test concentrations were coincident with reductions in cladocerans and indicated secondary effects of the insecticide on the abundance of microzooplankton. There were no significant differences among treated and control enclosures in chlorophyll a concentrations, indicating that tebufenozide did not have direct effects on phytoplankton biomass, nor did the alterations in the zooplankton communities of treated enclosures have measurable secondary effects on phytoplankton biomass. Daytime dissolved oxygen concentrations were significantly higher in treated enclosures than in controls, indicating that the perturbation to biotic communities of some treated enclosures was sufficient to induce measurable changes in system-level functional attributes. Recovery of zooplankton communities in the enclosures occurred within 1-2 months at 0.07 and 0.13 mg l(-1) and by the following summer (12-13 months) at 0.33 and 0.66 mg l(-1).

  16. Use of sunlight to degrade oxytetracycline in marine aquaculture's waters

    International Nuclear Information System (INIS)

    Leal, J.F.; Esteves, V.I.; Santos, E.B.H.

    2016-01-01

    Oxytracycline (OTC) is a broad spectrum antibiotic authorized for use in European aquaculture. Its photo-degradation has been widely studied in synthetic aqueous solutions, sometimes resorting to expensive methods and without proven effectiveness in natural waters. Thus, this work studied the possibility to apply the solar photo-degradation for removal of OTC from marine aquaculture's waters. For that, water samples were collected at different locals of the water treatment circuit, from two different aquaculture companies. Water samples were firstly characterized regarding to pH, salinity, total suspended solids (TSS), organic carbon and UV–Vis spectroscopic characteristics. Then, the samples were spiked with OTC and irradiated using simulated sunlight in order to evaluate the matrix effects on OTC photo-degradation. From kinetic results, the apparent quantum yields and the outdoor half-life times, at 40°N for midsummer and midwinter days were estimated by the first time for these conditions. For a midsummer day, at sea level, the outdoor half-life time predicted for OTC in these aquaculture's waters ranged between 21 and 25 min. Additionally, the pH and salinity effects on the OTC photo-degradation were evaluated and it has been shown that high pH values and the presence of sea salt increase the OTC photo-degradation rate in aquaculture's waters, compared to results in deionised water. The results are very promising to apply this low-cost methodology using the natural sunlight in aquaculture's waters to remove OTC. - Highlights: • Oxytetracycline (OTC) is one of the most used antibiotics in aquaculture. • OTC photolysis in marine aquaculture's water is faster than in deionised water. • The sunlight radiation quickly remove the OTC from aquaculture's water. • Outdoor half-life for a midsummer day is 21–25 min in aquaculture's water. • High pH's and salinities increase the OTC photo-degradation. - This work

  17. Impact resistant battery enclosure systems

    Science.gov (United States)

    Tsutsui, Waterloo; Feng, Yuezhong; Chen, Weinong Wayne; Siegmund, Thomas Heinrich

    2017-10-31

    Battery enclosure arrangements for a vehicular battery system. The arrangements, capable of impact resistance include plurality of battery cells and a plurality of kinetic energy absorbing elements. The arrangements further include a frame configured to encase the plurality of the kinetic energy absorbing elements and the battery cells. In some arrangements the frame and/or the kinetic energy absorbing elements can be made of topologically interlocked materials.

  18. Success Stories in Asian Aquaculture | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    13 oct. 2009 ... Sena S. De Silva is Director General of the Network of Aquaculture Centres in Asia- Pacific and Honorary Professor of Aquaculture and Fisheries Biology at the School of Life and Environmental Sciences, Deakin University, Victoria, Australia. F. Brian Davy is Senior Fellow at the International Institute for ...

  19. Analysis of sound absorption performance of an electroacoustic absorber using a vented enclosure

    Science.gov (United States)

    Cho, Youngeun; Wang, Semyung; Hyun, Jaeyub; Oh, Seungjae; Goo, Seongyeol

    2018-03-01

    The sound absorption performance of an electroacoustic absorber (EA) is primarily influenced by the dynamic characteristics of the loudspeaker that acts as the actuator of the EA system. Therefore, the sound absorption performance of the EA is maximum at the resonance frequency of the loudspeaker and tends to degrade in the low-frequency and high-frequency bands based on this resonance frequency. In this study, to adjust the sound absorption performance of the EA system in the low-frequency band of approximately 20-80 Hz, an EA system using a vented enclosure that has previously been used to enhance the radiating sound pressure of a loudspeaker in the low-frequency band, is proposed. To verify the usefulness of the proposed system, two acoustic environments are considered. In the first acoustic environment, the vent of the vented enclosure is connected to an external sound field that is distinct from the sound field coupled to the EA. In this case, the acoustic effect of the vented enclosure on the performance of the EA is analyzed through an analytical approach using dynamic equations and an impedance-based equivalent circuit. Then, it is verified through numerical and experimental approaches. Next, in the second acoustic environment, the vent is connected to the same external sound field as the EA. In this case, the effect of the vented enclosure on the EA is investigated through an analytical approach and finally verified through a numerical approach. As a result, it is confirmed that the characteristics of the sound absorption performances of the proposed EA system using the vented enclosure in the two acoustic environments considered in this study are different from each other in the low-frequency band of approximately 20-80 Hz. Furthermore, several case studies on the change tendency of the performance of the EA using the vented enclosure according to the critical design factors or vent number for the vented enclosure are also investigated. In the future

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    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...

  1. Promoting Women Participation in Aquaculture as a Viable Tool for ...

    African Journals Online (AJOL)

    Promoting Women Participation in Aquaculture as a Viable Tool for Poverty Alleviation in the Rural Areas of Nigeria. ... Open Access DOWNLOAD FULL TEXT ... a source of income, also the paper focus on the roles of women in aquaculture, ...

  2. 9 CFR 3.53 - Primary enclosures.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Primary enclosures. 3.53 Section 3.53 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL... maintained in good repair to protect the rabbits from injury, to contain them, and to keep predators out. (2...

  3. Standard Guide for Testing Materials for Aerospace Plastic Transparent Enclosures

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This guide is intended to summarize the standard test methods available on individual and composite materials utilized in fabrication of aerospace plastic transparent enclosures. As such, it is intended to specifically include transparent thermoplastics, transparent elastomers, and reinforced plastics, whether thermoplastic or thermosetting. 1.2 This guide is intended as an aid in the search for test methods pertinent to Aerospace Plastic Transparent Enclosures. It should be understood that all methods listed may not apply to all enclosures. 1.3 The standards included refer to the properties or aspects listed in Table 1. The properties or aspects are listed in alphabetical order and the descriptions used are intended to facilitate the search. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limi...

  4. Characteristics of Bacterial Communities in Cyanobacteria-Blooming Aquaculture Wastewater Influenced by the Phytoremediation with Water Hyacinth

    Directory of Open Access Journals (Sweden)

    Qing Zhou

    2017-12-01

    Full Text Available Cyanobacterial blooms often occur in aquaculture wastewater in China. A floating plant, water hyacinth has been widely used to treat this wastewater. Little is known, however, about bacterial community characteristics and the risk of potential pathogens in cyanobacteria-blooming aquaculture wastewater remediated by water hyacinth. In wastewater treated with water hyacinth, we used culture enumeration and high-throughput sequencing to explore the characteristics of bacterial communities, the status of coliform bacteria, and pathogenic bacteria potentially conducive to human disease. Our results indicated that the relative abundance of Acidobacteria, Planctomycetes, Actinobacteria, Chlorobi, Cyanobacteria, Proteobacteria, and phylum OD1 in cyanobacteria-blooming aquaculture wastewater were significantly influenced by water hyacinth. After 30 days, the relative abundance of Proteobacteria and phylum OD1 in the water hyacinth treatments increased remarkably, while the relative abundance of the other 5 phyla in treatment was significantly reduced compared with the controls. In 21 major families, the relative abundance of Comamonadaceae, Oxalobacteraceae, Rhodocylclaceae, and an unnamed group from phylum OD1 increased significantly in the water hyacinth treatments compared with the controls. The number of total coliforms in wastewater treated by water hyacinth was significantly elevated and higher than controls during the first 6–18 days, with the maximum reaching 23,800 MPN/L. The level of potential pathogenic bacteria in wastewater treated by water hyacinth significantly reduced compared with the controls after 18 days, but it significantly increased from the initial level. It appears that water hyacinth by itself is not an effective treatment for reducing potential pathogens in aquaculture water.

  5. Enclosure environment characterization testing for the base line validation of computer fire simulation codes

    International Nuclear Information System (INIS)

    Nowlen, S.P.

    1987-03-01

    This report describes a series of fire tests conducted under the direction of Sandia National Laboratories for the US Nuclear Regulatory Commission. The primary purpose of these tests was to provide data against which to validate computer fire environment simulation models to be used in the analysis of nuclear power plant enclosure fire situations. Examples of the data gathered during three of the tests are presented, though the primary objective of this report is to provide a timely description of the test effort itself. These tests were conducted in an enclosure measuring 60x40x20 feet constructed at the Factory Mutual Research Corporation fires test facility in Rhode Island. All of the tests utilized forced ventilation conditions. The ventilation system was designed to simulate typical nuclear power plant installation practices and ventilation rates. A total of 22 tests using simple gas burner, heptane pool, methanol pool, and PMMA solid fires was conducted. Four of these tests were conducted with a full-scale control room mockup in place. Parameters varied during testing were fire intensity, enclosure ventilation rate, and fire location. Data gathered include air temperatures, air velocities, radiative and convective heat flux levels, optical smoke densities, inner and outer enclosure surface temperatures, enclosure surface heat flux levels, and gas concentrations within the enclosure in the exhaust stream

  6. Cold Climate Building Enclosure Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Kosny, Jan [Fraunhofer CSE, Cambridge, MA (United States); Fallahi, Ali [Fraunhofer CSE, Cambridge, MA (United States); Shukla, Nitin [Fraunhofer CSE, Cambridge, MA (United States)

    2013-01-01

    This project investigates the energy performance and cost effectiveness of several state-of-the-art retrofit strategies that could be used in triple-deckers and colonial houses, common house types in New England. Several emerging building enclosure technologies were integrated, including high R-value aerogel and vacuum insulations, in forms that would be energy efficient, flexible for different retrofit scenarios, durable, and potentially cost-competitive for deep energy retrofits.

  7. Electric devices used in radioactive handling enclosures of the high activity laboratory

    International Nuclear Information System (INIS)

    Gaigeot, F.; Laurent, H.

    1958-08-01

    This report describes several electric, electronic and electromechanical assemblies which are used in radioactive handling enclosures. The authors propose an overview of existing or foreseen devices: a device to lift covers, a brightness comparator, a high voltage device to perform electrophoresis, a level sensor or regulator device, a regulation device to control under-pressure in an enclosure [fr

  8. DIAGNOSIS OF AQUACULTURE IN THE MUNICIPALITY OF ALVARADO VERACRUZ, MEXICO

    Directory of Open Access Journals (Sweden)

    Lenin Rangel-López

    2014-07-01

    Full Text Available This research aims to analyze the current situation of aquaculture farms in the Municipality of Alvarado, Veracruz, Mexico. During this study, 29 interviews were conducted aimed to the units of aquaculture producers; 24 variables were analyzed within the aspects of the socio-economic, technical, marketing and legal framework. The most relevant results within the legal framework: 21% of units has “National Registration of Fisheries and Aquaculture” (RNPyA and 7% has “Federal Taxpayer Register” (RFC; in the socio-economic aspects: 187 jobs are generated; on technical aspects: the average area for cultivation is 410.11 ha, 79% of production is Tilapia (Oreochromis spp.. The aquaculture activity on Alvarado, Veracruz, it is in a learning process, therefore strategies are needed in order to the development of the activity and increasing production; improving cultivation methodologies and training producers on managing their aquaculture units.

  9. Future challanges for the maturing Norwegian salmon aquaculture industry

    DEFF Research Database (Denmark)

    Asche, Frank; Guttormsen, Atle G.; Nielsen, Rasmus

    2013-01-01

    In this paper, we analyze total factor productivity change in the Norwegian salmon aquaculture sector from 1996 to 2008. During this period, the production has on average been growing with 8% per year. At the same time, the price of salmon has stabilized indicating that an increase in demand...... factor to future production growth in the salmon aquaculture industry....

  10. An Educational Laboratory Experiment to Demonstrate the Development of Fires in a Long Enclosure

    Science.gov (United States)

    Moinuddin, Khalid

    2013-01-01

    This paper is aimed at describing an experiment involving flame-front movement across the fuel package located within long enclosures and associated heat transfer mechanism. There is a growing interest in incorporating safety education in the chemical engineering curriculum, especially in relation to "facility siting." This experiment is…

  11. Optimal External-Memory Planar Point Enclosure

    DEFF Research Database (Denmark)

    Arge, Lars; Samoladas, Vasilis; Yi, Ke

    2007-01-01

    .g. spatial and temporal databases, and is dual to the important and well-studied orthogonal range searching problem. Surprisingly, despite the fact that the problem can be solved optimally in internal memory with linear space and O(log N+K) query time, we show that one cannot construct a linear sized......In this paper we study the external memory planar point enclosure problem: Given N axis-parallel rectangles in the plane, construct a data structure on disk (an index) such that all K rectangles containing a query point can be reported I/O-efficiently. This problem has important applications in e...... external memory point enclosure data structure that can be used to answer a query in O(log  B N+K/B) I/Os, where B is the disk block size. To obtain this bound, Ω(N/B 1−ε ) disk blocks are needed for some constant ε>0. With linear space, the best obtainable query bound is O(log 2 N+K/B) if a linear output...

  12. Numerical modeling of buoyancy-driven turbulent flows in enclosures

    International Nuclear Information System (INIS)

    Hsieh, K.J.; Lien, F.S.

    2004-01-01

    Modeling turbulent natural convection in enclosures with differentially heated vertical walls is numerically challenging, in particular, when low-Reynolds-number (low-Re) models are adopted. When the turbulence level in the core region of cavity is low, most low-Re models, particular those showing good performance for bypass transitional flows, tend to relaminarize the flow and, as a consequence, significantly underpredict the near-wall turbulence intensities and boundary-layer thickness. Another challenge associated with low-turbulence buoyancy-driven flows in enclosures is its inherent unsteadiness, which can pose convergence problems when a steady Reynolds-averaged Navier-Stokes (RANS) equation is solved. In the present study, an unsteady RANS approach in conjunction with the low-Re k-ε model of Lien and Leschziner [Int. J. Comput. Fluid Dyn. 12 (1999) 1] is initially adopted and the predicted flow field is found effectively relaminarized. To overcome this difficulty, likely caused by the low-Re functions in the ε-equation, the two-layer approach is attempted, in which ε is prescribed algebraically using the one-equation k-l model of Wolfshtein [Int. J. Heat Mass Transfer 12 (1969) 301]. The two-layer approach combined with a quadratic stress-strain relation gives overall the best performance in terms of mean velocities, temperature and turbulence quantities

  13. A Study of the Aquaculture Industry in Texas to Assist in Establishing Aquaculture as a Course Offering in Agricultural Science and Technology. Final Report.

    Science.gov (United States)

    Dillingham, John; And Others

    A 1989-90 project determined the knowledge and skills necessary for employment in the aquaculture industry. The study identified technical materials and other resources available in private industry and higher education institutions. Two surveys determined the status of aquaculture in Texas school districts and identified tasks performed by…

  14. An Intelligent Four-Electrode Conductivity Sensor for Aquaculture

    OpenAIRE

    Zhang , Jiaran; Li , Daoliang; Wang , Cong; Ding , Qisheng

    2012-01-01

    International audience; Conductivity is regard as a key technical parameter in modern intensive fish farming management. The water conductivity sensors are sophisticated devices used in the aquaculture monitoring field to understand the effects of climate changes on fish ponds. In this paper a new four-electrode smart sensor is proposed for water conductivity measurements of aquaculture monitoring.The main advantages of these sensors include a high precision, a good stability and an intrinsic...

  15. Drama of the commons in small-scale shrimp aquaculture in northwestern, Sri Lanka

    Directory of Open Access Journals (Sweden)

    Eranga Kokila Galappaththi

    2015-03-01

    Full Text Available Aquaculture, and shrimp aquaculture in particular, can have major social and environmental impacts. However, aquaculture remains an understudied area in commons research. Can aspects of commons theory be applied to solve problems of aquaculture? We examined three coastal community-based shrimp aquaculture operations in northwestern Sri Lanka using a case study approach. These shrimp farms were individually owned by small producers and managed under local-level rules designed by cooperatives (samithis. The common-pool resource of major interest was water for aquaculture ponds, obtained from an interconnected common water body. We evaluated the shrimp farming social-ecological system by using Ostrom’s design principles for collective action. Key elements of the system were: clearly defined boundaries; collaboratively designed crop calendar, bottom-up approach involving community associations, multi-level governance, and farmers-and-government collaborative structures. Together, these elements resolved the excludability and subtractability problems of commons by establishing boundary and membership rules and collective choice rules.

  16. Remote Sensing Approach for Documenting the Conversion of Mangroves to Aquaculture

    Science.gov (United States)

    Peneva, E.

    2007-12-01

    The loss of mangrove forests to aquaculture, particularly shrimp farming, in coastal Thailand presents serious environmental and societal problems. Shrimp farming is one of the fastest growing aquaculture sectors in many parts of the world, as well as one of the most controversial. In spite of considerable work put into understanding the impacts of shrimp aquaculture, few studies provide detailed assessment of the issue through time. This research compares three change detection techniques (Object-based; Change Vector Analysis (CVA); and Integrated GIS and Remote Sensing) in order to assess the mangrove conversion caused by aquaculture development in Krabi Province, Thailand between 1989, 2001 and 2007 using Landsat TM data. All three methods provide valuable information though each has its own merits. Preliminary results show 40% loss of mangroves between 1989 and 2007, 25% of which is to aquaculture development, 10% to urban, and 5% to agricultural land. This study will help establish a methodology that will aid coastal communities in Southeast Asia in determining sustainable land use management approaches.

  17. Solar greenhouse aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Toever, W V

    1979-01-01

    Rainbow and Speckled Trout have been successfully hatched and reared in a recirculating aquaculture system. The system is integrated into the Ark greenhouse providing thermal mass for temperature regulation and supplying nutrient-rich water for plants. The system incorporates bacterial, algal and hydroponic water filtration. Various vegetable crops have been raised in the hydroponic troughs. A scaled-down system suitable for domestic solar greenhouse application is also under development.

  18. Probiotics as Antiviral Agents in Shrimp Aquaculture

    Directory of Open Access Journals (Sweden)

    Bestha Lakshmi

    2013-01-01

    Full Text Available Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

  19. Genetic manipulations in aquaculture: a review of stock improvement by classical and modern technologies.

    Science.gov (United States)

    Hulata, G

    2001-01-01

    The aim of this review was to highlight the extent to which the genetic technologies are implemented by the aquaculture industry. The review shows that some of the modern genetic technologies are already extensively applied by the diverse aquaculture industries, though not to the same extent for all important aquacultured species (according to FAO 1998 figures). Some species (common carp, Atlantic salmon, rainbow trout, channel catfish, Nile tilapia, and the Pacific oyster) received concentrated breeding efforts, while other major cultured species (Chinese and Indian carps and the giant tiger shrimp) received, so far, relatively limited attention, and a few species (Yesso scallop, blue mussel, white Amur bream, and milkfish) have, apparently, not been genetically improved at all. Most of the genetically improved strains reaching the aquaculture industry were developed through traditional selective breeding (selection, crossbreeding, and hybridization). Emerging, more modern technologies for genetic manipulation seem to take 10-20 years from being established experimentally until applications affect the industry. Thus, chromosome-set and sex manipulations started to affect the industry during the 1980's and 1990's. DNA marker technology and gene manipulations have yet hardly affected the industry. The former have not matured yet, but hold much promise. The latter could have affected the industry already had it not been restricted by public concern.

  20. Capacity building for sustainable aquaculture and fisheries development in Myanmar

    NARCIS (Netherlands)

    Steins, N.A.; Bosma, R.H.; Taal, K.; Bolman, B.C.; Bink, E.; Dop, van H.; Dekker, A.; Numan, J.; Spek, van der G.; Pijl, van der W.

    2015-01-01

    This report presents the results of a Dutch public-private capacity building (Knowledge to Knowledge or K2K) mission for fostering sustainable aquaculture and fisheries development in Myanmar. The objectives of the K2K mission were to: 1) analyse Myanmar’s aquaculture and fisheries knowledge

  1. Experimental Study on Natural Convection Heat Transfer From two Parallel Horizontal Cylinders in Horizontal Cylindrical Enclosure

    Directory of Open Access Journals (Sweden)

    Ahmed T. Ahmed

    2013-05-01

    Full Text Available  An experimental study on natural convection heat transfer from two parallel horizontal cylinders in horizontal cylindrical enclosure was carried out under condition of constant surfaces temperature for two cylinders and cylindrical enclosure. The study included the effect of Rayleigh number, rotation angle that represent the confined angle between the passing horizontal plane in cylindrical enclosure center and passing line in two cylinders centers, and the spaces between two cylinders on their heat loss ability.39An experimental set-up was used for this purpose which consist watercontainer, test section which is formed of plastic cylinder that represent the cylindrical enclosure, and two heating elements which are formed of two copper cylinders with (19 mm in diameters heated internally by electrical sources that represents transfer and heat loss elements through this set-up.      The experiments were done at the range of Rayleigh number between ( , cylinders rotation angle at ( , and spacing ratio at ( .     The study showed that the ability of heat loss from two cylinders is a function of Rayleigh number, cylinders rotation angle, and the spaces between them. This ability is increased by increasing of Rayleigh number and it was showed that this ability reaches maximum value at the first cylinder ( and minimum value at the second cylinder ( at spacing ratio (S/D=3 and rotation angle ( for the first and ( for the second cylinder respectively.      The effective variables on natural convection heat transfer from the above two cylinders are related by two correlating equations, each one explains dimensionless relation of heat transfer from each cylinder that represented by Nusselt number against Rayleigh number, rotation angle, and the spacing ratio between two cylinders. 

  2. Natural convection in enclosures. Proceedings of the nineteenth national heat transfer conference, Orlando, FL, July 27-30, 1980

    International Nuclear Information System (INIS)

    Torrance, K.E.; Catton, I.

    1980-01-01

    Natural convection in low aspect ratio rectangular enclosures is considered along with three-dimensional convection within rectangular boxes, natural convection flow visualization in irradiated water cooled by air flow over the surface, free convection in vertical slots, the stratification in natural convection in vertical enclosures, the flow structure with natural convection in inclined air-filled enclosures, and natural convection across tilted, rectangular enclosures of small aspect ratio. Attention is given to the effect of wall conduction and radiation on natural convection in a vertical slot with uniform heat generation of the heated wall, a numerical study of thermal insulation enclosure, free convection in a piston-cylinder enclosure with sinusoidal piston motion, natural convection heat transfer between bodies and their spherical enclosure, an experimental study of the steady natural convection in a horizontal annulus with irregular boundaries, three-dimensional natural convection in a porous medium between concentric inclined cylinders, a numerical solution for natural convection in concentric spherical annuli, and heat transfer by natural convection in porous media between two concentric spheres

  3. Aquaculture in the ecosystem

    National Research Council Canada - National Science Library

    Holmer, M; Black, K; Duarte, C.M; Marba, N; Kakakassis, I

    2008-01-01

    ... aquaculture is one of the fastest growing industries in the world, comparable to the computer technology industry (Chapters 9 and 10). The demand for marine products is controlled by a complexity of factors in our society, not least the increasing human population and the increasing global affluence that allows the consumer to buy higher price...

  4. Design and Application of a Solar Mobile Pond Aquaculture Water Quality-Regulation Machine Based in Bream Pond Aquaculture.

    Science.gov (United States)

    Liu, Xingguo; Xu, Hao; Ma, Zhuojun; Zhang, Yongjun; Tian, Changfeng; Cheng, Guofeng; Zou, Haisheng; Lu, Shimin; Liu, Shijing; Tang, Rong

    2016-01-01

    Bream pond aquaculture plays a very important role in China's aquaculture industry and is the main source of aquatic products. To regulate and control pond water quality and sediment, a movable solar pond aquaculture water quality regulation machine (SMWM) was designed and used. This machine is solar-powered and moves on water, and its primary components are a solar power supply device, a sediment lifting device, a mechanism for walking on the water's surface and a control system. The solar power supply device provides power for the machine, and the water walking mechanism drives the machine's motion on the water. The sediment lifting device orbits the main section of the machine and affects a large area of the pond. Tests of the machine's mechanical properties revealed that the minimum illumination necessary for the SMWM to function is 13,000 Lx and that its stable speed on the water is 0.02-0.03 m/s. For an illumination of 13,000-52,500 Lx, the sediment lifting device runs at 0.13-0.35 m/s, and its water delivery capacity is 110-208 m(3)/h. The sediment lifting device is able to fold away, and the angle of the suction chamber can be adjusted, making the machine work well in ponds at different water depths from 0.5 m to 2 m. The optimal distance from the sediment lifting device to the bottom of the pond is 10-15 cm. In addition, adjusting the length of the connecting rod and the direction of the traction rope allows the SMWM to work in a pond water area greater than 80%. The analysis of water quality in Wuchang bream (Parabramis pekinensis) and silver carp (Hypophthalmichthys molitrix) culture ponds using the SMWM resulted in decreased NH3(+)-N and available phosphorus concentrations and increased TP concentrations. The TN content and the amount of available phosphorus in the sediment were reduced. In addition, the fish production showed that the SMWM enhanced the yields of Wuchang bream and silver carp by more than 30% and 24%, respectively. These results

  5. Noise pollution of air compressor and its noise reduction procedures by using an enclosure

    Directory of Open Access Journals (Sweden)

    Farhad Forouharmajd

    2012-01-01

    Conclusions: An overall noise reduction by 25 dB with the use of mineral wool as an extra liner on the inside of the enclosure, suggests that the effectiveness of the enclosure can be increased by using such absorber materials.

  6. Land-based salmon aquacultures change the quality and bacterial degradation of riverine dissolved organic matter

    Science.gov (United States)

    Kamjunke, Norbert; Nimptsch, Jorge; Harir, Mourad; Herzsprung, Peter; Schmitt-Kopplin, Philippe; Neu, Thomas R.; Graeber, Daniel; Osorio, Sebastian; Valenzuela, Jose; Carlos Reyes, Juan; Woelfl, Stefan; Hertkorn, Norbert

    2017-03-01

    Aquacultures are of great economic importance worldwide but pollute pristine headwater streams, lakes, and estuaries. However, there are no in-depth studies of the consequences of aquacultures on dissolved organic matter (DOM) composition and structure. We performed a detailed molecular level characterization of aquaculture DOM quality and its bacterial degradation using four salmon aquacultures in Chile. Fluorescence measurements, ultrahigh-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy of the DOM revealed specific and extensive molecular alterations caused by aquacultures. Aquacultures released large quantities of readily bioavailable metabolites (primarily carbohydrates and peptides/proteins, and lipids), causing the organic matter downstream of all the investigated aquacultures to deviate strongly from the highly processed, polydisperse and molecularly heterogeneous DOM found in pristine rivers. However, the upstream individual catchment DOM signatures remained distinguishable at the downstream sites. The benthic algal biovolume decreased and the bacterial biovolume and production increased downstream of the aquacultures, shifting stream ecosystems to a more heterotrophic state and thus impairing the ecosystem health. The bacterial DOM degradation rates explain the attenuation of aquaculture DOM within the subsequent stream reaches. This knowledge may aid the development of improved waste processing facilities and may help to define emission thresholds to protect sensitive stream ecosystems.

  7. Evolution of Integrated Open Aquaculture Systems in Hungary: Results from a Case Study

    Directory of Open Access Journals (Sweden)

    József Popp

    2018-01-01

    Full Text Available This article presents the history of integrated farming in aquaculture through a Hungarian case study. The development of Hungarian integrated aquaculture is aligned with global trends. In the previous millennium, the utilization of the nutrients introduced into the system was the main aspect of the integration. In Hungary, technologies that integrated fish production with growing crops and animal husbandry appeared, including for example: large-scale fish-cum-rice production; fish-cum-duck production; and integrated pig-fish farming which were introduced in the second half of the 20th century. Today, the emphasis is on integrating the use of the kind of feed where the main goal is to minimize nutrient loads in the surrounding natural ecosystems and to maximize the utilization of the unit’s water resources. The various modern integrated freshwater aquaculture systems, such as intensive fish production combined with wetland, recirculation aquaculture system and multi-functional aquaculture, have proved their viability. However, the future opportunities for these systems have not always been properly recognized and acknowledged when the future of European aquaculture is discussed.

  8. Measure Guideline: Deep Energy Enclosure Retrofit for Double-Stud Walls

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, H. [Building Science Corporation, Westford, MA (United States); Pettit, B. [Building Science Corporation, Westford, MA (United States)

    2015-06-01

    This Measure Guideline describes a deep energy enclosure retrofit (DEER) solution that provides insulation to the interior of the wall assembly with the use of a double stud wall. The guide describes two approaches to retrofitting the existing the walls: one involving replacement of the existing cladding, and the other that leaves the existing cladding in place. It discusses the design principles related to the use of various insulation types, and provides strategies and procedures for implementing the double stud wall retrofit. It also evaluates important moisture-related and indoor air quality measures that need to be implemented to achieve a durable, high performance wall.

  9. Measure Guideline: Deep Energy Enclosure Retrofit for Double-Stud Walls

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, H. [Building Science Corporation, Westford, MA (United States); Pettit, B. [Building Science Corporation, Westford, MA (United States)

    2015-06-22

    This Measure Guideline describes a deep energy enclosure retrofit solution that provides insulation to the interior of the wall assembly with the use of a double-stud wall. The guide describes two approaches to retrofitting the existing walls—one that involves replacing the existing cladding and the other that leaves the cladding in place. This guideline also covers the design principles related to the use of various insulation types and provides strategies and procedures for implementing the double-stud wall retrofit. It also includes an evaluation of important moisture-related and indoor air quality measures that need to be implemented to achieve a durable high-performance wall.

  10. 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...

  11. The impact and control of biofouling in marine aquaculture: a review.

    Science.gov (United States)

    Fitridge, Isla; Dempster, Tim; Guenther, Jana; de Nys, Rocky

    2012-01-01

    Biofouling in marine aquaculture is a specific problem where both the target culture species and/or infrastructure are exposed to a diverse array of fouling organisms, with significant production impacts. In shellfish aquaculture the key impact is the direct fouling of stock causing physical damage, mechanical interference, biological competition and environmental modification, while infrastructure is also impacted. In contrast, the key impact in finfish aquaculture is the fouling of infrastructure which restricts water exchange, increases disease risk and causes deformation of cages and structures. Consequently, the economic costs associated with biofouling control are substantial. Conservative estimates are consistently between 5-10% of production costs (equivalent to US$ 1.5 to 3 billion yr(-1)), illustrating the need for effective mitigation methods and technologies. The control of biofouling in aquaculture is achieved through the avoidance of natural recruitment, physical removal and the use of antifoulants. However, the continued rise and expansion of the aquaculture industry and the increasingly stringent legislation for biocides in food production necessitates the development of innovative antifouling strategies. These must meet environmental, societal, and economic benchmarks while effectively preventing the settlement and growth of resilient multi-species consortia of biofouling organisms.

  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...... and/or economic reasons.A potential alternative technology for removing nitrate currently applied for treating surface and drainage water is based on using wood by-products as a carbon source for denitrification. Using lab-scale horizontal-flow woodchip filters, the current study investigated...... 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...

  13. Variation in some quality attributes of Atlantic salmon fillets from aquaculture related to geographic origin and water temperature

    DEFF Research Database (Denmark)

    Johansson, Gine Ørnholt; Frosch, Stina; Jørgensen, Bo Munk

    2017-01-01

    an efficient use of the information gathered in the different links of the value chain, a deeper knowledge of the correlations between the various quality attributes and factors like the geographical origin of the salmon, the company and the water temperature of the fish farm, is needed. In the present study......It is well know that factors like fat content and texture affect the yield when making products from Atlantic salmon (Salmo salar L.). The relation between these factors and other quality attributes like water holding capacity and protein content, however, has received limited attention. To enable...... a multivariate approach was taken to investigate the variation in some quality parameters (fat, protein, texture, water holding capacity, weight) amongst salmon samples (n = 136) from Norwegian aquaculture in order to establish which parameters were accounting for most of the variation seen in relation...

  14. Development of a seaweed species-selection index for successful culture in a seaweed-based integrated aquaculture system

    Science.gov (United States)

    Kang, Yun Hee; Hwang, Jae Ran; Chung, Ik Kyo; Park, Sang Rul

    2013-03-01

    Integrated multi-trophic aquaculture (IMTA) has been proposed as a concept that combines the cultivation of fed aquaculture species ( e.g., finfish/shrimp) with extractive aquaculture species ( e.g., shellfish/seaweed). In seaweed-based integrated aquaculture, seaweeds have the capacity to reduce the environmental impact of nitrogen-rich effluents on coastal ecosystems. Thus, selection of optimal species for such aquaculture is of great importance. The present study aimed to develop a seaweed species-selection index for selecting suitable species in seaweed-based integrated aquaculture system. The index was synthesized using available literature-based information, reference data, and physiological seaweed experiments to identify and prioritize the desired species. Undaria pinnatifida, Porphyra yezoensis and Ulva compressa scored the highest according to a seaweed-based integrated aquaculture suitability index (SASI). Seaweed species with the highest scores were adjudged to fit the integrated aquaculture systems. Despite the application of this model limited by local aquaculture environment, it is considered to be a useful tool for selecting seaweed species in IMTA.

  15. Innovative enclosure dome/observing aperture system design for the MROI Array Telescopes

    Science.gov (United States)

    Busatta, A.; Marchiori, G.; Mian, S.; Payne, I.; Pozzobon, M.

    2010-07-01

    The close-pack array of the MROI necessitated an original design for the Unit Telescope Enclosure (UTE) at Magdalena Ridge Observatory. The Magdalena Ridge Observatory Interferometer (MROI) is a project which comprises an array of up to ten (10) 1.4m diameter mirror telescopes arranged in a "Y" configuration. Each of these telescopes will be housed inside a Unit Telescope Enclosure (UTE) which are relocatable onto any of 28 stations. The most compact configuration includes all ten telescopes, several of which are at a relative distance of less than 8m center to center from each other. Since the minimum angle of the field of regard is 30° with respect to the horizon, it is difficult to prevent optical blockage caused by adjacent UTEs in this compact array. This paper presents the design constraints inherent in meeting the requirement for the close-pack array. An innovative design enclosure was created which incorporates an unique dome/observing aperture system. The description of this system focuses on how the field of regard requirement led to an unique and highly innovative concept that had to be able to operate in the harsh environmental conditions encountered at an altitude of 10,460ft (3,188m). Finally, we describe the wide use of composites materials and structures (e.g. glass/carbon fibres, sandwich panels etc.) on the aperture system which represents the only way to guarantee adequate thermal and environmental protection, compactness, structural stability and limited power consumption due to reduced mass.

  16. Enclosure for small animals during awake animal imaging

    Science.gov (United States)

    Goddard, Jr., James S

    2013-11-26

    An enclosure or burrow restrains an awake animal during an imaging procedure. A tubular body, made from a radiolucent material that does not attenuate x-rays or gamma rays, accepts an awake animal. A proximal end of the body includes an attachment surface that corresponds to an attachment surface of an optically transparent and optically uniform window. An anti-reflective coating may be applied to an inner surface, an outer surface, or both surfaces of the window. Since the window is a separate element of the enclosure and it is not integrally formed as part of the body, it can be made with optically uniform thickness properties for improved motion tracking of markers on the animal with a camera during the imaging procedure. The motion tracking information is then used to compensate for animal movement in the image.

  17. Steroids accumulate in the rearing water of commercial recirculating aquaculture systems

    NARCIS (Netherlands)

    Mota, V.C.; Martins, C.I.; Eding, E.H.; Canário, A.V.M.; Verreth, J.A.J.

    2014-01-01

    Little information is available on steroid concentrations in the rearing water of aquaculture systems and whether they accumulate in recirculating aquaculture systems (RAS). Therefore this study aimed at determining (1) the concentrations and variation of cortisol and sex steroids in RAS, (2) the

  18. Perception of Aquaculture Education to Support Further Growth of Aquaculture Industry in Victoria, Australia

    Science.gov (United States)

    Awal, Sadiqul; Christie, Andrew; Watson, Matthew; Hannadige, Asanka G. T.

    2012-01-01

    Purpose: The central aim of this study was to determine the perception of aquaculture educational provisions in the state of Victoria, and whether they are sufficient to ultimately support further growth of the industry. Design/methodology/approach: Questionnaires were formulated and distributed to participants in a variety of ways, including via…

  19. Disease in marine aquaculture

    Science.gov (United States)

    Sindermann, C. J.

    1984-03-01

    It has become almost a truism that success in intensive production of animals must be based in part on development of methods for disease diagnosis and control. Excellent progress has been made in methods of diagnosis for major pathogens of cultivated fish, crustacean and molluscan species. In many instances these have proved to be facultative pathogens, able to exert severe effects in populations of animals under other stresses (marginal physical or chemical conditions; overcrowding). The concept of stress management as a critical prophylactic measure is not new, but its significance is being demonstrated repeatedly. The particular relationship of water quality and facultative pathogens such as Vibrio, Pseudomonas and Aeromonas species has been especially apparent. Virus diseases of marine vertebrates and invertebrates — little known two decades ago — are now recognized to be of significance to aquaculture. Virus infections of oysters, clams, shrimps and crabs have been described, and mortalities have been attributed to them. Several virus diseases of fish have also been recognized as potential or actual problems in culture. In some instances, the pathogens seem to be latent in natural populations, and may be provoked into patency by stresses of artificial environments. One of the most promising approaches to disease prophylaxis is through immunization. Fish respond well to various vaccination procedures, and new non-stressing methods have been developed. Vibriosis — probably the most severe disease of ocean-reared salmon — has been controlled to a great extent through use of a polyvalent bacterin, which can be modified as new pathogenic strains are isolated. Prophylactic immunization for other bacterial diseases of cultivated fish has been attempted, especially in Japan, with some success. There is also some evidence that the larger crustaceans may be immunologically responsive, and that at least short-term protection may be afforded to cultured

  20. Abundance of plankton population densities in relation to bottom soil textural types in aquaculture ponds

    Directory of Open Access Journals (Sweden)

    F. Siddika

    2012-06-01

    Full Text Available Plankton is an important food item of fishes and indicator for the productivity of a water body. The present study was conducted to evaluate the effects of bottom soil textural conditions on abundance of plankton in aquaculture pond. The experiment was carried out using three treatments, i.e., ponds bottom with sandy loam (T1, with loam (T2 and with clay loam (T3. The ranges of water quality parameters analyzed were suitable for the growth of plankton during the experimental period. Similarly, chemical properties of soil were also within suitable ranges and every parameter showed higher ranges in T2. A total 20 genera of phytoplankton were recorded belonged to Chlorophyceae (7, Cyanophyceae (5, Bacillariophyceae (5, Euglenophyceae (2 and Dinophyceae (1. On the other hand, total 13 genera of zooplankton were recorded belonged to Crustacea (7 and Rotifera (6. The highest ranges of phytoplankton and zooplankton densities were found in T2 where low to medium-type bloom was observed during the study period. Consequently, the mean abundance of plankton (phytoplankton and zooplankton density was significantly highest in T2. The highest abundance of plankton in the T2 indicated that pond bottom with loamy soil is suitable for the growth and production of plankton in aquaculture ponds.

  1. Success Stories in Asian Aquaculture

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Asia, the epicenter of aquaculture production, the traditional practices tend to be ...... In addition to supporting the development of the International Principles for ...... Government also provided income tax exemption schemes to small scale ...... Forum held in 30th November 2004 in Hotel Equatorial, Penang, Malaysia, 12.

  2. Stensund wastewater aquaculture. Studies of key factors for its optimization

    Energy Technology Data Exchange (ETDEWEB)

    Guterstam, B.; Forsberg, L.E. [Stensund Ecological Center, Stensunds Fold Center, S-61991 Trosa (Sweden); Buczynska, A. [Faculty of Process and Environmental Engineering, Technical University of Lodz, 175 Wolczanska strasse, PL-90942 Lodz (Poland); Frelek, K. [Department of Analytical Chemistry, Medical University of Gdansk, Al. Gen. J. Hallera 107, PL-80416 Gdansk (Poland); Pilkaityte, R. [Natural Science Faculty, University of Klaipeda, LT-5813 Klaipeda (Lithuania); Reczek, L. [Department of Water Supply and Sewage Systems, Warsaw Agricultural University, 166 Nowoursynowska strasse, PL-02787 Warsaw (Poland); Rucevska, I. [Latvian Environmental Data Center, Straumes 2, Jurmala LV 2015 (Latvia)

    1998-10-21

    This paper is a summary of an in-depth study of key factors in the function of a 7-year-old aquaculture system designed for treatment and recycling of domestic wastewater at Stensund, Trosa, Sweden. The reported areas are: wastewater flows, reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), phosphorus, nitrogen, and fecal bacteria. Plant production is recorded as harvested biomass, and energy results are given as generated heat and electricity consumption. Special studies were conducted on the reduction of copper by anaerobic treatment. Nitrification was studied with different filter media. Microalgal autofocculation of phosphorus was studied in relation to pH and water hardness for the green algal genus Scenedesmus. Limiting factors for the growth of Daphnia magna in the zooplankton step of the constructed aquatic food-web was studied in a specially designed reproduction test. The results are analyzed in order to optimize the function of the wastewater aquaculture

  3. Electromagnetic coupling between transmitters and electro-explosive devices located within an enclosure.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Jorgenson, Roy Eberhardt; Coats, Rebecca Sue

    2010-04-01

    This report documents calculations conducted to determine if 42 low-power transmitters located within a metallic enclosure can initiate electro-explosive devices (EED) located within the same enclosure. This analysis was performed for a generic EED no-fire power level of 250 mW. The calculations show that if the transmitters are incoherent, the power available is 32 mW - approximately one-eighth of the assumed level even with several worst-case assumptions in place.

  4. Carp feeding activity and habitat utilisation in relation to supplementary feeding in a semi-intensive aquaculture pond

    Czech Academy of Sciences Publication Activity Database

    Jurajda, Pavel; Adámek, Zdeněk; Roche, Kevin Francis; Mrkvová, Markéta; Štarhová, Dagmar; Prášek, Václav; Zukal, Jan

    2016-01-01

    Roč. 24, č. 6 (2016), s. 1627-1640 ISSN 0967-6120 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Cyprinus carpio * telemetry * fish diet * fat content * pond aquaculture * water quality Subject RIV: EG - Zoology Impact factor: 1.095, year: 2016

  5. 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.

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

    International Nuclear Information System (INIS)

    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 5 kg/year of fish, 1.5 x 10 6 kg/year of clam meat, and 1.5 x 10 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

  7. Land-based salmon aquacultures change the quality and bacterial degradation of riverine dissolved organic matter

    DEFF Research Database (Denmark)

    Kamjunke, Norbert; Nimptsch, Jorge; Harir, Mourad

    2017-01-01

    characterization of aquaculture DOM quality and its bacterial degradation using four salmon aquacultures in Chile. Fluorescence measurements, ultrahigh-resolution mass spectrometry, and nuclear magnetic resonance spectroscopy of the DOM revealed specific and extensive molecular alterations caused by aquacultures...

  8. Optimizing the design and impact behavior of a polymeric enclosure

    International Nuclear Information System (INIS)

    Singh, R.; Mattoo, A.; Saigal, A.

    2006-01-01

    This paper focuses on the application of finite element analysis to design an electronic enclosure with improved impact resistance properties. With the growing push towards miniaturization there is a constant decrease in the wall thickness of the enclosure applications. This necessitates use of ribs to enhance the impact resistance. This study aims at investigating optimal design of ribs for improving impact resistance. The 'DSGZ' phenomenological constitutive model, which uniformly describes the entire range of stress-strain constitutive relationship of polymers under any monotonic loading mode is used to predict the plastic failure energies. Several simulation runs were performed based on the design parameters using a 2 3 factorial design of experiments. The results from these simulations were used to analyze and study the various design parameters and its influence on the impact energy. It was found that when designing enclosures with ribs with an objective to maximize the impact failure energy, stress should be laid on optimizing the ratio of wall thickness to rib height within permissible limits while center-to-center spacing between the ribs and rib thickness do not have a significant effect

  9. Optimizing the design and impact behavior of a polymeric enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Singh, R. [Department of Mechanical Engineering, Tufts University, Medford, MA 02155 (United States); Mattoo, A. [Department of Mechanical Engineering, Tufts University, Medford, MA 02155 (United States); Saigal, A. [Department of Mechanical Engineering, Tufts University, Medford, MA 02155 (United States)]. E-mail: anil.saigal@tufts.edu

    2006-07-01

    This paper focuses on the application of finite element analysis to design an electronic enclosure with improved impact resistance properties. With the growing push towards miniaturization there is a constant decrease in the wall thickness of the enclosure applications. This necessitates use of ribs to enhance the impact resistance. This study aims at investigating optimal design of ribs for improving impact resistance. The 'DSGZ' phenomenological constitutive model, which uniformly describes the entire range of stress-strain constitutive relationship of polymers under any monotonic loading mode is used to predict the plastic failure energies. Several simulation runs were performed based on the design parameters using a 2{sup 3} factorial design of experiments. The results from these simulations were used to analyze and study the various design parameters and its influence on the impact energy. It was found that when designing enclosures with ribs with an objective to maximize the impact failure energy, stress should be laid on optimizing the ratio of wall thickness to rib height within permissible limits while center-to-center spacing between the ribs and rib thickness do not have a significant effect.

  10. The Numerical Study on the Influence of Prandtl Number and Height of the Enclosure

    International Nuclear Information System (INIS)

    Moon, Je-Young; Chung, Bum-Jin

    2016-01-01

    This study investigated numerically the internal flow depending on Prandtl number of fluid and height of enclosure. The two-dimensional numerical simulations were performed for several heights of enclosure in the range between 0.01 m and 0.074 m. It corresponds to the aspect ratio (H/L) ranged from 0.07 to 0.5. Prandtl number was 0.2, 0.7 and 7. Rayleigh number based on the height of enclosure ranged between 8.49x10 3 and 1.20x10 8 . The numerical calculations were carried out using FLUENT 6.3. In order to confirm the influence of Prandtl number and height of side walls on the internal flow and heat transfer of the horizontal enclosure, the numerical study is carried out using the FLUENT 6.3. The numerical results for the condition of top cooling only agree well with Rayleigh-Benard natural convection. When the top and side walls were cooled, the internal flow of enclosure is more complex. The thickness of thermal and velocity boundary layer varies with Prandtl number. For Pr>1 the behavior of cells is unstable and irregular owing to the entrained plume, whereas the internal flow for Pr<1 is stable and regular. Also, the number of cells increases depending on decrease of height. As a result, the heat exchange increases

  11. Factors affecting wild rabbit production in extensive breeding enclosures: how can we optimise efforts?

    Directory of Open Access Journals (Sweden)

    José Guerrero-Casado

    2013-09-01

    Full Text Available The declining rabbit population in the Iberian Peninsula has led hunters and authorities to rear rabbits in captivity systems for their subsequent release. One alternative method to intensive rabbitry systems is the use of extensive breeding enclosures, since they produce animals of greater quality for hunting and conservation purposes. However, some of the factors that affect rabbit production in breeding enclosures are still unknown. The present study used partial least squares regression (PLSR to analyse the effects of plot size, scrub cover, slope, initial rabbit abundance, the resources needed to dig warrens, predation and proximity to other enclosures on rabbit abundance. The results of our study show a positive effect of the number of other fenced plots within a radius of 3 km, a positive relationship with the availability of optimal resources for building warrens and a positive influence of intermediate values of scrub cover. According to our results, to maximise rabbit production in the enclosures it would be advisable to concentrate the restocking effort by ensuring that the restocking plots are close to each other, thus avoiding isolated enclosures. Furthermore, the selection of plots with an appropriate scrub cover and high availability of elements that favour the construction of warrens, such as large stones, sloping land or tall shrubs, may optimise results.

  12. Survival and growth of fish (Lates calcarifer under integrated mangrove-aquaculture and open-aquaculture systems

    Directory of Open Access Journals (Sweden)

    Shanmugaarasu Venkatachalam

    2018-02-01

    Full Text Available The potential use of mangrove swamp for fish farming industry is not clearly known. Therefore, current study was conducted to assess the growth performance of the Asian Seabass, Lates calcarifer cultivated in integrated mangrove-aquaculture system (IMAS and open aquaculture system without mangroves (OAS. Fish survival and biomass production were higher by 11% and 12.5% respectively in the IMAS than those in the OAS. The fish growth performance was higher in monsoon than that in other seasons. It was in association with water quality parameters such as, high levels of DO, chlorophylls-a,b, nitrate-N, DOC, TOC; low levels of light intensity, temperature (air, water, SPM, chlorophyll-c, nitrite-N, ammonia, total phosphate, reactive silicate, and POC; as well with moderate salinity. The water quality seemed to be favourable for growth and survival of the fish. Therefore, integrating the mangroves with fish farming of the Asian seabass is beneficial for better fish survival and biomass production.

  13. Application of tuned sound enclosures to transformers

    International Nuclear Information System (INIS)

    Allan, K.N.; Ellingson, E.F.

    1992-09-01

    The objective of this program was to reduce the noise emitted from power transformers by using a close-fitting, integrally-mounted noise shell. The noise shell consists of a series of panels mounted to a framework, that is, in turn, supported by the tank by means of mounting brackets and neoprene isolators. The development work was directed specifically toward application to existing transformers, i.e. retrofit.This project is a follow-on to work done under project RP-579-1. That project developed the theory and applied it experimentally to an existing transformer. The results were somewhat disappointing, however, with an 8 dBA reduction achieved where 15 dBA was expected. This document reports the work performed covering the period from March 1, 1977, to December 31, 1978. A complete noise shell enclosure was installed on a transformer for Consumers Power Company (Jackson, Michigan). Costs projected on the basis of this installation and several business assumptions indicate an installed cost of 19.8% of a new, standard noise transformer. This is higher than originally expected, but lower than alternative noise control methods. It also has some features that should make it an even more attractive alternative. Material loss factor (generally termed damping) of the enclosure material was found to be a critical parameter. Addition of a damping treatment to the experimental shell increased the performance to the 15 dBA target reduction. Damping was also found to be critical on the demonstration unit. The plastic panels installed (loss factor 0.05) resulted in a noise reduction of 8.5 dBA, increasing to 11.6 dBA when acoustical foam was added inside the enclosure. Three panels were replaced with damped steel panels and an overall 16.5 dBA reduction is anticipated based on vibration measurements

  14. 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.

  15. A new neolithic circular enclosure in Central Germany

    Science.gov (United States)

    Kretzer, Olaf

    2015-08-01

    Today we know about 130 neolithic enclosures in Central Europe. About 20 of them are located in Germany. In the last years, there was a great discussion about the function of the openings: Are the openings aligned with points of the solstices? Or are the openings aligned with points of rising stars?Four years ago, a new neolithic circular enclosure was found in the northern part of Thuringia. With a diameter of about 50 meters it was not so large but it was the first evidence of a neolithic culture in Thuringia: the central part of Germany!7000 years ago, people with unknown identity built up three rings with three or four openings.With the help of various measurements we were able to determine in which directions the openings were aligned. We found a link between these directions and very interesting landmarks - an amazing connection between sky and landscape.

  16. Probabilistic risk assessment of veterinary medicines applied to four major aquaculture species produced in ASIA

    NARCIS (Netherlands)

    Rico, A.; Brink, van den P.J.

    2014-01-01

    Aquaculture production constitutes one of the main sources of pollution with veterinary medicines into the environment. About 90% of the global aquaculture production is produced in Asia and the potential environmental risks associated with the use of veterinary medicines in Asian aquaculture have

  17. Macroalgal biomonitors of trace metal contamination in acid sulfate soil aquaculture ponds.

    Science.gov (United States)

    Gosavi, K; Sammut, J; Gifford, S; Jankowski, J

    2004-05-25

    Earthen shrimp aquaculture ponds are often impacted by acid sulfate soils (ASS), typically resulting in increased disease and mortality of cultured organisms. Production losses have been attributed to either low pH or to elevated concentrations of toxic metals, both direct products of pyrite oxidation in ASS. The standard farm management practice to minimise effects of pyrite oxidation is to maintain pH of pond waters above 5, based on the assumption that dissolved metal bioavailability is negligible at this pH. This study aimed to test the validity of this assumption, and therefore elucidate a possible role of toxic heavy metals in observed decreases in farm productivity. Metal bioaccumulation in four genera of macroalgae, Ulva sp., Enteromorpha sp., Cladophora sp. and Chaetomorpha sp., sampled from ASS-affected shrimp aquaculture ponds were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) to assess the relative bioavailability of dissolved metals within the system. Results showed that all four genera of macroalgae accumulated appreciable quantities of Fe, Al, Zn, Cd, Cu, As and Pb. Iron and Al, the most common metals mobilised from ASS, were both accumulated in all algal genera to concentrations three orders of magnitude greater than all other metals analysed. These findings indicate that dissolved heavy metals are indeed bioavailable within the aquaculture pond system. A literature search of heavy metal bioaccumulation by these algal genera revealed concentrations recorded in this study are comparable to highly contaminated environments, such as those exposed to urban, industrial and mining pollution. The results of this study indicate that dissolved metal bioavailability in many earthen shrimp aquaculture ponds may be higher than previously thought.

  18. A review on the potential of aquaculture development in Kenya for ...

    African Journals Online (AJOL)

    A review on the potential of aquaculture development in Kenya for poverty alleviation and food security. ... It is estimated that another 40 million metric tonnes of aquatic food will be required by the year 2030. Today ... Key words: Fish production, capture fisheries, culture systems, Economic Stimulus Programme, aquaculture ...

  19. Economic valuation of a mangrove ecosystem threatened by shrimp aquaculture in Sri Lanka.

    Science.gov (United States)

    Gunawardena, M; Rowan, J S

    2005-10-01

    Mangrove ecosystems in Sri Lanka are increasingly under threat from development projects, especially aquaculture. An economic assessment is presented for a relatively large (42 ha) shrimp culture development proposed for the Rekawa Lagoon system in the south of Sri Lanka, which involved an extended cost-benefit analysis of the proposal and an estimate of the "total economic value" (TEV) of a mangrove ecosystem. The analysis revealed that the internal benefits of developing the shrimp farm are higher than the internal costs in the ratio of 1.5:1. However, when the wider environmental impacts are more comprehensively evaluated, the external benefits are much lower than the external costs in a ratio that ranges between 1:6 and 1:11. In areas like Rekawa, where agriculture and fisheries are widely practiced at subsistence levels, shrimp aquaculture developments have disproportionately large impacts on traditional livelihoods and social welfare. Thus, although the analysis retains considerable uncertainties, more explicit costing of the environmental services provided by mangrove ecosystems demonstrates that low intensity, but sustainable, harvesting has far greater long-term value to local stakeholders and the wider community than large shrimp aquaculture developments.

  20. Flows and Stratification of an Enclosure Containing Both Localised and Vertically Distributed Sources of Buoyancy

    Science.gov (United States)

    Partridge, Jamie; Linden, Paul

    2013-11-01

    We examine the flows and stratification established in a naturally ventilated enclosure containing both a localised and vertically distributed source of buoyancy. The enclosure is ventilated through upper and lower openings which connect the space to an external ambient. Small scale laboratory experiments were carried out with water as the working medium and buoyancy being driven directly by temperature differences. A point source plume gave localised heating while the distributed source was driven by a controllable heater mat located in the side wall of the enclosure. The transient temperatures, as well as steady state temperature profiles, were recorded and are reported here. The temperature profiles inside the enclosure were found to be dependent on the effective opening area A*, a combination of the upper and lower openings, and the ratio of buoyancy fluxes from the distributed and localised source Ψ =Bw/Bp . Industrial CASE award with ARUP.

  1. Review of the RNA Interference Pathway in Molluscs Including Some Possibilities for Use in Bivalves in Aquaculture

    Directory of Open Access Journals (Sweden)

    Leigh Owens

    2015-03-01

    Full Text Available Generalised reviews of RNA interference (RNAi in invertebrates, and for use in aquaculture, have taken for granted that RNAi pathways operate in molluscs, but inspection of such reviews show little specific evidence of such activity in molluscs. This review was to understand what specific research had been conducted on RNAi in molluscs, particularly with regard to aquaculture. There were questions of whether RNAi in molluscs functions similarly to the paradigm established for most eukaryotes or, alternatively, was it more similar to the ecdozoa and how RNAi may relate to disease control in aquaculture? RNAi in molluscs appears to have been only investigated in about 14 species, mostly as a gene silencing phenomenon. We can infer that microRNAs including let-7 are functional in molluscs. The genes/proteins involved in the actual RNAi pathways have only been rudimentarily investigated, so how homologous the genes and proteins are to other metazoa is unknown. Furthermore, how many different genes for each activity in the RNAi pathway are also unknown? The cephalopods have been greatly overlooked with only a single RNAi gene-silencing study found. The long dsRNA-linked interferon pathways seem to be present in molluscs, unlike some other invertebrates and could be used to reduce disease states in aquaculture. In particular, interferon regulatory factor genes have been found in molluscs of aquacultural importance such as Crassostrea, Mytilus, Pinctada and Haliotis. Two possible aquaculture scenarios are discussed, zoonotic norovirus and ostreid herpesvirus 1 to illustrate the possibilities. The entire field of RNAi in molluscs looks ripe for scientific exploitation and practical application.

  2. How is shrimp aquaculture transforming coastal livelihoods and lagoons in Estero Real, Nicaragua? The need to integrate social-ecological research and ecosystem-based approaches.

    Science.gov (United States)

    Benessaiah, Karina; Sengupta, Raja

    2014-08-01

    Ecosystem-based approaches to aquaculture integrate environmental concerns into planning. Social-ecological systems research can improve this approach by explicitly relating ecological and social dynamics of change at multiple scales. Doing so requires not only addressing direct effects of aquaculture but also considering indirect factors such as changes in livelihood strategies, governance dynamics, and power relations. We selected the community of Puerto Morazán, Nicaragua as a case study to demonstrate how the introduction of small-scale aquaculture radically transformed another key livelihood activity, lagoon shrimp fishing, and the effects that these changes have had on lagoons and the people that depend on them. We find that shrimp aquaculture played a key role in the collapse, in the 1990s, of an existing lagoon common-property management. Shrimp aquaculture-related capital enabled the adoption of a new fishing technique that not only degraded lagoons but also led to their gradual privatization. The existence of social ties between small-scale shrimp farmers and other community members mitigated the impacts of privatization, illustrating the importance of social capital. Since 2008, community members are seeking to communally manage the lagoons once again, in response to degraded environmental conditions and a consolidation of the shrimp industry at the expense of smaller actors. This research shows that shrimp aquaculture intersects with a complex set of drivers, affecting not only how ecosystems are managed but also how they are perceived and valued. Understanding these social-ecological dynamics is essential to implement realistic policies and management of mangrove ecosystems and address the needs of resource-dependent people.

  3. Productivity of a coral reef using boundary layer and enclosure methods

    Science.gov (United States)

    McGillis, W.R.; Langdon, C.; Loose, B.; Yates, K.K.; Corredor, Jorge

    2011-01-01

    The metabolism of Cayo Enrique Reef, Puerto Rico, was studied using in situ methods during March 2009. Benthic O2 fluxes were used to calculate net community production using both the boundary layer gradient and enclosure techniques. The boundary layer O2 gradient and the drag coefficients were used to calculate productivity ranging from -12.3 to 13.7 mmol O2 m-2 h-1. Productivity measurements from the enclosure method ranged from -11.0 to 12.9 mmol O2 m-2 h-1. During the study, the mean hourly difference between the methods was 0.65 mmol O2 m-2 h-1 (r2 = 0.92), resulting in well-reconciled estimates of net community production between the boundary layer (-33.1 mmol m-2 d-1) and enclosure (-46.3 mmol m-2 d-1) techniques. The results of these independent approaches corroborate quantified rates of metabolism at Cayo Enrique Reef. Close agreement between methods demonstrates that boundary layer measurements can provide near real-time assessments of coral reef health.

  4. REVIEW OF AQUACULTURAL PRODUCTION SYSTEM MODELS

    African Journals Online (AJOL)

    user

    models of aquacultural production systems with the aim of adopting a suitable one for ... of predicting the environmental condition, so as to determine point of diminishing returns and optimize yield in an ..... sale of fish are also tracked.

  5. 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.

  6. Coordinated effort to advance genomes-to-phenomes through the integration of bioinformatics with aquaculture research

    Science.gov (United States)

    Aquaculture is the fastest growing food production system in the world. The research program at the USDA-ARS-SNARC strives to improve the efficiency and sustainability of warmwater U.S. aquaculture. SNARC scientists have impacted the catfish (#1 U.S. aquaculture industry), tilapia (#3) and hybrid st...

  7. Effects of Dredging and Lanthanum-Modified Clay on Water Quality Variables in an Enclosure Study in a Hypertrophic Pond

    Directory of Open Access Journals (Sweden)

    Miquel Lürling Guido Waajen

    2017-05-01

    Full Text Available An enclosure experiment was conducted between July and September 2009 to compare the effectiveness of a phosphate fixative, the lanthanum-modified bentonite clay Phoslock® (LMB, dredging, and their combination in controlling eutrophication in a hypertrophic urban pond in Heesch, The Netherlands. In total, 25 water quality variables were monitored. Multivariate analysis revealed that the combination LMB-treated and dredged enclosures deviated most from the pond (reference and the controls, and showed the strongest eutrophication reduction. Overall, dredging significantly increased transparency, lowered turbidity, and improved the oxygen conditions in the enclosures compared to non-dredged ones. Nonetheless, one dredged enclosure deviated dramatically from the others, which might reflect methodological issues with dredging. The LMB treatment appeared to be less effective at mitigating eutrophication than dredging, and phosphate concentrations even increased during the experiment in the LMB-treated enclosures. Chemical equilibrium modeling suggested that humic substances could have formed complexes with lanthanum (La from the LMB, rendering it unavailable for intercepting P over the course of the enclosure experiment. Residual lanthanum concentrations in combination dredging and LMB treatments exceeded the Dutch standard 10-fold. Total zooplankton abundance, and particularly Cladocera, increased in all enclosures over the course of the experiment. The limited effect of LMB in the enclosure experiment and the violation of the Dutch La standard when combined with dredging disqualify LMB as an intervention agent in the restoration of the pond.

  8. The potential for eEngineering enhanced functional-feed soybeans for sustainable aquaculture feed

    Directory of Open Access Journals (Sweden)

    Eliot eHerman

    2016-04-01

    Full Text Available Aquaculture is the most rapidly growing segment of global animal production that now surpasses wild-capture fisheries production and is continuing to grow 10% annually. Sustainable aquaculture needs to diminish, and progressively eliminate, its dependence on fishmeal-sourced feed from over-harvestedallocated fisheries. Sustainable aquafeed sources will need to be primarily of plant-origin. Soybean is currently the primary global vegetable-origin protein source for aquaculture. Direct exchange of soybean meal for fishmeal in aquafeed has resulted in reduced growth rates due in part to soybean’s anti-nutritional proteins. To produce an aquaculture soybeans for use in aquaculture feeds a new conventional line has been bred termed Triple Null by stacking null alleles for the feed-relevant proteins Kunitz Trypsin Inhibitor, lectin, and P34 allergen. Triple Null is now being further enhanced as a platform to build additional transgene traits for production disease vaccines, altered protein composition, and to produce high levels of -carotene an intrinsic orange-colored aquafeed marker to distinguish the seeds from commodity beans and as the metabolic feedstock precursor of highly valued astaxanthin.

  9. Effect of flow rate on environmental variables and phytoplankton dynamics: results from field enclosures

    Science.gov (United States)

    Zhang, Haiping; Chen, Ruihong; Li, Feipeng; Chen, Ling

    2015-03-01

    To investigate the effects of flow rate on phytoplankton dynamics and related environment variables, a set of enclosure experiments with different flow rates were conducted in an artificial lake. We monitored nutrients, temperature, dissolved oxygen, pH, conductivity, turbidity, chlorophyll- a and phytoplankton levels. The lower biomass in all flowing enclosures showed that flow rate significantly inhibited the growth of phytoplankton. A critical flow rate occurred near 0.06 m/s, which was the lowest relative inhibitory rate. Changes in flow conditions affected algal competition for light, resulting in a dramatic shift in phytoplankton composition, from blue-green algae in still waters to green algae in flowing conditions. These findings indicate that critical flow rate can be useful in developing methods to reduce algal bloom occurrence. However, flow rate significantly enhanced the inter-relationships among environmental variables, in particular by inducing higher water turbidity and vegetative reproduction of periphyton ( Spirogyra). These changes were accompanied by a decrease in underwater light intensity, which consequently inhibited the photosynthetic intensity of phytoplankton. These results warn that a universal critical flow rate might not exist, because the effect of flow rate on phytoplankton is interlinked with many other environmental variables.

  10. DKIST enclosure modeling and verification during factory assembly and testing

    Science.gov (United States)

    Larrakoetxea, Ibon; McBride, William; Marshall, Heather K.; Murga, Gaizka

    2014-08-01

    The Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST) is unique as, apart from protecting the telescope and its instrumentation from the weather, it holds the entrance aperture stop and is required to position it with millimeter-level accuracy. The compliance of the Enclosure design with the requirements, as of Final Design Review in January 2012, was supported by mathematical models and other analyses which included structural and mechanical analyses (FEA), control models, ventilation analysis (CFD), thermal models, reliability analysis, etc. During the Enclosure Factory Assembly and Testing the compliance with the requirements has been verified using the real hardware and the models created during the design phase have been revisited. The tests performed during shutter mechanism subsystem (crawler test stand) functional and endurance testing (completed summer 2013) and two comprehensive system-level factory acceptance testing campaigns (FAT#1 in December 2013 and FAT#2 in March 2014) included functional and performance tests on all mechanisms, off-normal mode tests, mechanism wobble tests, creation of the Enclosure pointing map, control system tests, and vibration tests. The comparison of the assumptions used during the design phase with the properties measured during the test campaign provides an interesting reference for future projects.

  11. Offshore finfish aquaculture in the United States: An examination of federal laws that could be used to address environmental and occupational public health risks.

    Science.gov (United States)

    Fry, Jillian P; Love, David C; Shukla, Arunima; Lee, Ryan M

    2014-11-19

    Half of the world's edible seafood comes from aquaculture, and the United States (US) government is working to develop an offshore finfish aquaculture industry in federal waters. To date, US aquaculture has largely been regulated at the state level, and creating an offshore aquaculture industry will require the development of a new regulatory structure. Some aquaculture practices involve hazardous working conditions and the use of veterinary drugs, agrochemicals, and questionable farming methods, which could raise environmental and occupational public health concerns if these methods are employed in the offshore finfish industry in the US. This policy analysis aims to inform public health professionals and other stakeholders in the policy debate regarding how offshore finfish aquaculture should be regulated in the US to protect human health; previous policy analyses on this topic have focused on environmental impacts. We identified 20 federal laws related to offshore finfish aquaculture, including 11 that are relevant to preventing, controlling, or monitoring potential public health risks. Given the novelty of the industry in the US, myriad relevant laws, and jurisdictional issues in an offshore setting, federal agencies need to work collaboratively and transparently to ensure that a comprehensive and functional regulatory structure is established that addresses the potential public health risks associated with this type of food production.

  12. Aquaculture en milieu rural au Sri Lanka | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le Sri Lanka se tourne vers l'aquaculture pour diversifier son économie rurale et accroître sa production alimentaire, particulièrement dans les provinces du nord et de l'est du pays, qui se relèvent du conflit civil. Bien que l'aquaculture représente une stratégie de sécurité alimentaire prometteuse, elle doit être gérée de ...

  13. Consumer preferences for sustainable aquaculture products: Evidence from in-depth interviews, think aloud protocols and choice experiments.

    Science.gov (United States)

    Risius, Antje; Janssen, Meike; Hamm, Ulrich

    2017-06-01

    Fish from aquaculture is becoming more important for human consumption. Sustainable aquaculture procedures were developed as an alternative to overcome the negative environmental impacts of conventional aquaculture procedures and wild fisheries. The objective of this contribution is to determine what consumers expect from sustainable aquaculture and whether they prefer sustainable aquaculture products. A combination of qualitative research methods, with think aloud protocols and in-depth interviews, as well as quantitative methods, using choice experiments and face-to-face interviews, was applied. Data was collected in three different cities of Germany. Results revealed that sustainable aquaculture was associated with natural, traditional, local, and small scale production systems with high animal welfare standards. Overall, participants paid a lot of attention to the declaration of origin; in particular fish products from Germany and Denmark were preferred along with local products. Frequently used sustainability claims for aquaculture products were mostly criticized as being imprecise by the participants of the qualitative study; even though two claims tested in the choice experiments had a significant positive impact on the choice of purchase. Similarly, existing aquaculture-specific labels for certified sustainable aquaculture had an impact on the buying decision, but were not well recognized and even less trusted. Overall, consumers had a positive attitude towards sustainable aquaculture. However, communication measures and labelling schemes should be improved to increase consumer acceptance and make a decisive impact on consumers' buying behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Climate adaptation and innovation in Mekong aquaculture ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Climate adaptation and innovation in Mekong aquaculture – AQUADAPT Mekong ... severe weather events and rising sea levels that impact regional hydrology. ... Research and Development Institute, Cambodia; National University of Laos; ...

  15. Limiting enclosures. Method of control of the leak rate per hour. Enclosures of classes 1 and 2. Method of measurement of the increase of the oxygen titre in volume

    International Nuclear Information System (INIS)

    1984-07-01

    The present standard can be applied to limiting enclosures working under depression or overpressure. It can be applied to limiting enclosures used for works on radioactive or toxic materials. The leak rate per hour is -2 h -1 . The measuring method uses oxygen determination after the enclusore is filled with an inert gas. The influence of pressure and temperature are analysed. The measurement installation and its operating way are presented; the accuracy of the method given. This standard supersedes the experimental standard of December 1982 [fr

  16. Natural convection in wavy enclosures with volumetric heat sources

    International Nuclear Information System (INIS)

    Oztop, H.F.; Varol, Y.; Abu-Nada, E.; Chamkha, A.

    2011-01-01

    In this paper, the effects of volumetric heat sources on natural convection heat transfer and flow structures in a wavy-walled enclosure are studied numerically. The governing differential equations are solved by an accurate finite-volume method. The vertical walls of enclosure are assumed to be heated differentially whereas the two wavy walls (top and bottom) are kept adiabatic. The effective governing parameters for this problem are the internal and external Rayleigh numbers and the amplitude of wavy walls. It is found that both the function of wavy wall and the ratio of internal Rayleigh number (Ra I ) to external Rayleigh number (Ra E ) affect the heat transfer and fluid flow significantly. The heat transfer is predicted to be a decreasing function of waviness of the top and bottom walls in case of (IRa/ERa)>1 and (IRa/ERa)<1. (authors)

  17. Direct simulation of natural convection in square porous enclosure

    International Nuclear Information System (INIS)

    Pourshaghaghy, A.; Hakkaki-Fard, A.; Mahdavi-Nejad, A.

    2007-01-01

    In this article, natural convection in a square porous enclosure is simulated by a direct numerical method. The solution method is based on a random distribution of solid blocks, which resembles the porous media within the cavity. The Navier-Stokes equations are solved directly in the fluid region without the assumption of volume averaging. The no-slip condition is applied on the surface of any solid particle, and the energy transport equation is solved separately for the solid phase and fluid flow. The local and average Nusselt numbers are presented for steady state for two different cases of thermal boundary conditions of the cavity walls. An oscillatory solution is observed for the local Nu number on the surface of the enclosure, and the critical Ra numbers are found in which natural convection flow is started within the cavity

  18. Ozonation control and effects of ozone on water quality in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Rojas-Tirado, Paula Andrea; Chetri, Ravi K.

    2018-01-01

    To address the undesired effect of chemotherapeutants in aquaculture, ozone has been suggested as an alternative to improve water quality. To ensure safe and robust treatment, it is vital to define the ozone demand and ozone kinetics of the specific water matrix to avoid ozone overdose. Different...... ozone dosages were applied to water in freshwater recirculating aquaculture systems (RAS). Experiments were performed to investigate ozone kinetics and demand, and to evaluate the effects on the water quality, particularly in relation to fluorescent organic matter. This study aimed at predicting...... a suitable ozone dosage for water treatment based on daily ozone demand via laboratory studies. These ozone dosages will be eventually applied and maintained at these levels in pilot-scale RAS to verify predictions. Selected water quality parameters were measured, including natural fluorescence and organic...

  19. 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.

  20. What shapes food value chains? Lessons from aquaculture in Asia

    DEFF Research Database (Denmark)

    Jespersen, Karen Sau; Kelling, I; Ponte, Stefano

    2014-01-01

    In this article, we explain what shapes food value chains through the analysis of selected aquaculture industries in four key Asian producing countries. Worldwide production of aquatic resources has grown rapidly in the past few decades, and aquaculture production in Asia has played a decisive role...... in this growth. We examine the main forms of coordination found along these value chains and the role that institutional frameworks play in governing them. We observe that negative publicity, driven by NGO and media campaigns, has led to increased use of third-party certification and the adoption of public...... and private standards. We find that the most sophisticated aquaculture operations in Asia are found in value chains led by retailers and branded processors and where the quality of domestic institutional frameworks has facilitated compliance with increasing demands from buyers overseas. Finally, we reflect...

  1. A continuous exchange factor method for radiative exchange in enclosures with participating media

    International Nuclear Information System (INIS)

    Naraghi, M.H.N.; Chung, B.T.F.; Litkouhi, B.

    1987-01-01

    A continuous exchange factor method for analysis of radiative exchange in enclosures is developed. In this method two types of exchange functions are defined, direct exchange function and total exchange function. Certain integral equations relating total exchange functions to direct exchange functions are developed. These integral equations are solved using Gaussian quadrature integration method. The results obtained based on the present approach are found to be more accurate than those of the zonal method

  2. Atlantic salmon breeding program at the National Cold Water Marine Aquaculture Center

    Science.gov (United States)

    The USDA-ARS National Cold Water Marine Aquaculture Center (NCWMAC) in Franklin, ME has been supporting the U.S. coldwater marine aquaculture industry for the past thirteen years by developing a genetically improved North American Atlantic salmon. The St. John's River stock was chosen as the focal ...

  3. Acoustic Pressure Waves in Vibrating 3-D Laminated Beam-Plate Enclosures

    Directory of Open Access Journals (Sweden)

    Charles A. Osheku

    2009-01-01

    Full Text Available The effect of structural vibration on the propagation of acoustic pressure waves through a cantilevered 3-D laminated beam-plate enclosure is investigated analytically. For this problem, a set of well-posed partial differential equations governing the vibroacoustic wave interaction phenomenon are formulated and matched for the various vibrating boundary surfaces. By employing integral transforms, a closed form analytical expression is computed suitable for vibroacoustic modeling, design analysis, and general aerospace defensive applications. The closed-form expression takes the form of a kernel of polynomials for acoustic pressure waves showing the influence of linear interface pressure variation across the axes of vibrating boundary surfaces. Simulated results demonstrate how the mode shapes and the associated natural frequencies can be easily computed. It is shown in this paper that acoustic pressure waves propagation are dynamically stable through laminated enclosures with progressive decrement in interfacial pressure distribution under the influence of high excitation frequencies irrespective of whether the induced flow is subsonic, sonic , supersonic, or hypersonic. Hence, in practice, dynamic stability of hypersonic aircrafts or jet airplanes can be further enhanced by replacing their noise transmission systems with laminated enclosures.

  4. 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...

  5. Aquaculture: a rapidly growing and significant source of sustainable food? Status, transitions and potential.

    Science.gov (United States)

    Little, D C; Newton, R W; Beveridge, M C M

    2016-08-01

    The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand.

  6. Aquaculture research and management in the telecoupled Belt and Road Initiative countries and beyond

    Science.gov (United States)

    Yang, W.; Ying, Z.; Marín, T.

    2017-12-01

    Due to the continuous growth in aquatic product consumption, globally the total production of aquatic products has increased by 20% in the past two decades. In 2014, for the first time, the production of aquatic products for direct human consumption from aquaculture surpassed that of wild catch. In 2016, the total production of global aquatic products reached 170 million tons, of which 45% comes from the aquaculture sector. More importantly, over 80% of the global aquaculture production occurs in the Belt and Road Initiative countries. Particularly, China alone contributes to two third of the global share. The rapid expansion and intensification of aquaculture have many environmental and socioeconomic impacts both at the cultivation places and also in places where feed is produced; however, these telecoupled processes and effects are largely unknown in a quantitative manner. Here, we apply the telecoupling framework to analyze the aquaculture trade among China and other Belt and Road Initiative countries and beyond. The integrated telecoupling framework helps to demonstrate the environmental and socioeconomic interactions among the feed (and aquatic product) sending, receiving, and spillover systems. It also provides a platform to model the telecoupled processes and effects across multiple remotely connected systems. Moreover, the application of the framework reveals many research gaps and management needs on aquaculture research and management.

  7. Fishmeal Supplier Evaluation and Selection for Aquaculture Enterprise Sustainability with a Fuzzy MCDM Approach

    Directory of Open Access Journals (Sweden)

    Tsung-Hsien Wu

    2017-11-01

    Full Text Available In the aquaculture industry, feed that is of poor quality or nutritionally imbalanced can cause problems including low weight, poor growth, poor palatability, and increased mortality, all of which can induce a decrease in aquaculture production. Fishmeal is considered a better source of protein and its addition as an ingredient in the aquafeed makes aquatic animals grow fast and healthy. This means that fishmeal is the most important feed ingredient in aquafeed for the aquaculture industry. For the aquaculture industry in Taiwan, about 144,000 ton/USD $203,245,000 of fishmeal was imported, mostly from Peru, in 2016. Therefore, the evaluation and selection of fishmeal suppliers is a very important part of the decision-making process for a Taiwanese aquaculture enterprise. This study constructed a multiple criteria decision-making evaluation model for the selection of fishmeal suppliers using the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR approach based on the weights obtained with the entropy method in a fuzzy decision-making environment. This hybrid approach could effectively and conveniently measure the comprehensive performance of the main Peruvian fishmeal suppliers for practical applications. In addition, the results and processes described herein function as a good reference for an aquaculture enterprise in making decisions when purchasing fishmeal.

  8. Modelling receiving water quality responses to brackishwater shrimp aquaculture farm effluents

    International Nuclear Information System (INIS)

    Roy Chaudhury, R.K.; Ramana Murty, V.; Ravindran, M.

    1999-01-01

    The objective was to perform a waste load allocation and determine the extent of aquaculture that the creeks can sustain, by meeting the water quality criteria for both the creek ecosystem and pond culture. Based on these results, similar assessments may be performed for other sites supporting large scale aquaculture activities. This paper introduces the sampling program and modelling methodology of the study

  9. 77 FR 50082 - Notice of Opportunity To Submit Content Request for the 2013 Census of Aquaculture

    Science.gov (United States)

    2012-08-20

    ... Content Request for the 2013 Census of Aquaculture AGENCY: National Agricultural Statistics Service... requests for the 2013 Census of Aquaculture. This census is required by law under the ``Census of... results of the 2005 Census of Aquaculture were released in October 2006. For more information, visit...

  10. Economic Valuation of Mangroves for Comparison with Commercial Aquaculture in South Sulawesi, Indonesia

    Directory of Open Access Journals (Sweden)

    Abdul Malik

    2015-08-01

    Full Text Available Mangroves are recognized as a provider of a variety of products and essential ecosystem services that contribute significantly to the livelihood of local communities. However, over the past decades, mangroves in many tropical areas including the Takalar district, South Sulawesi have degraded and decreased mainly due to conversion to aquaculture. Currently, little is known about the economic benefits of commercialization of aquaculture as compared to those derived from mangroves in the form of products and services. Here, we estimate the Total Economic Value (TEV of mangrove benefits in order to compare it with the benefit value of commercial aquaculture. Market prices, replacement costs, benefit transfer value and Cost-Benefit Analyses (CBA have been used for value determination and comparison. The results show that the per year TEV of mangroves in the study area (Takalar district, South Sulawesi was in the range of 4370 thousands USD (kUSD to 10,597 kUSD or 4 kUSD to 8 kUSD per hectare (the highest value contribution derived from the indirect use value (94%, whereas commercial aquaculture had a net benefit value of 228 kUSD or 3 kUSD per hectare. In addition, the comparison of Net Present Value (NPV between the benefit value of mangroves and that of commercial aquaculture revealed that conversion of mangroves into commercial aquaculture was not economically beneficial when the analysis was expanded to cover the costs of environmental and forest rehabilitation.

  11. Fishery and Aquaculture Relationship in the Mediterranean: Present and Future

    Directory of Open Access Journals (Sweden)

    G. RELINI

    2003-12-01

    Full Text Available Although the Mediterranean represents only 0.8% of the world seas, it is the site of a very long-established fishing activity, characterized mainly by multispecific catch and by artisanal or coastal activity, resulting from a mosaic of very diversified structures and gears, along more than 45,000 km of coastline. Two main biological features of this sea are the occurrence of a large richness of species (it represents 5.5% - 7% of world marine fauna and 16.6% of macrophyta, which stands in contrast with its ‘trophic poverty’ and the absence of large monospecific fishery, except for some small and large pelagic fish. Another biological characteristic of Mare Nostrumis the high invasion of exotic species, some exploited by fishery and aquaculture, some others quite dangerous. For the entire Mediterranean and Black Sea, the production (catch + aquaculture had been steadily increasing over the period 1972-1988 from 1,140,000 t to 2,080,000 t . The period 1988-1991 has shown a drastic drop in catches (in 1991: 1,400,000 t. From 1990 to 1995 the total catch increased to 1,701,379 t then decreased and in 2000 reached 1,485,046 t . In 2000 Turkey had the first place with 496,174 t, 26.9% of the total value (1,846,026 t, including fishing and aquaculture, followed by Italy with 25%, Greece 9%, Spain 7.6% and Algeria 5.4%. As in many parts of the world, aquaculture production in the Mediterranean is rapidly expanding. In 1970 the total aquaculture production was about 18,297 t of which 74.3% produced in Italy. In 2000 a value of 358,614 t was reached, about 1/4 of the total fishery catch, while the world aquaculture production corresponds to half of the world total catch. Italy is still the main producer with 46.7% , followed by Greece with 21.5%, Turkey 9.9% and France 6.7%. A sharp drop in the production of the European eel ( Anguilla anguilla and of the European flat oyster ( Ostrea edulis is recorded. Positive and negative interactions between

  12. MANAGEMENT OF SUSTAINABLE SEAWEED (Kappaphycus alvarezii AQUACULTURE IN THE CONTEXT OF CLIMATE CHANGE MITIGATION

    Directory of Open Access Journals (Sweden)

    Erlania Erlania

    2014-06-01

    Full Text Available Seaweed is an important aquaculture commodity that could contribute on climate change mitigation, related to its ability on absorbing CO2, as one of the green house gases, through photosynthesis. This study aimed to analyze seaweed potencies on carbon sequestration in the context of climate change mitigation while still resulting optimum production as primary purpose and to analyze the carrying capacity of Gerupuk Bay in order to manage sustainability of seaweed aquaculture. Seaweed, (Kappaphycus alvarezii was cultivated with long-line system in Gerupuk Bay, West Nusa Tenggara, during five months for three cultivation cycles. Samplings were conducted at days-15, 30, and 45 with CO2 absorption rates as main parameters. Water carrying capacity was calculated to determine the ability of Gerupuk Bay waters for supporting development of sustainable seaweed aquaculture. The results showed that absorption rates of CO2 by seaweed (K. alvarezii were different at each sampling days of cultivation periods; the highest value was at 10-20 days of cultivation. CO2 absorption analysis resulted based on sampling days of cultivation period could be appl ied to formulate the strategies for management of sustainable seaweed aquaculture, with optimal production and positively contributed to the environment. However, waters carrying capacity should also be considered as major aspect in the application of seaweed cultivation management, thus it can run continuously without causing conflicts with other interests.

  13. The Importance of Supratidal Habitats for Wintering Shorebirds and the Potential Impacts of Shrimp Aquaculture

    Science.gov (United States)

    Yasué, M.; Dearden, P.

    2009-06-01

    Intensive black tiger shrimp ( Penaeus monodon) aquaculture ponds have replaced significant areas of coastal wetlands throughout tropical Asia. Few studies have assessed potential impacts on avian foraging habitats. At Khao Sam Roi Yod National Park, Thailand, seminatural wetlands have been converted to either shrimp ponds or to salinization ponds that provide saline water for shrimp aquaculture. Although shorebirds cannot feed in aquaculture ponds, hypersaline ponds can provide productive foraging areas. Thus, the overall impact of the shrimp industry on shorebirds depends partly on the relative quality of the salt ponds compared to seminatural wetlands. In this study, we examined wintering shorebird use of tidal ( N = 5 sites) and supratidal areas (four wetland sites, four salt pond sites) and compared the shorebird community (14 species), prey availability, profitability, and disturbance rates between wetlands and salt ponds. Two shorebird species fed in higher densities in wetlands, whereas seven species were more abundant in salt ponds. Large juvenile fish and dragonfly larvae were more abundant in wetlands, whereas there were more small Chironomid midge and fly larvae in salt ponds. We conclude that salt ponds might provide higher-quality foraging habitats compared to wetlands for small shorebirds species because of the abundance of small larvae. However, the shrimp aquaculture industry reduces habitat availability for shorebirds feeding on larger prey. This study demonstrates a comprehensive, multispecies approach to assess the impacts of a large-scale change in coastal habitats for wintering shorebirds.

  14. Microplastics in the context of regulation of commercial shellfish aquaculture operations.

    Science.gov (United States)

    Schoof, Rosalind A; DeNike, Jesse

    2017-05-01

    Shellfish aquaculture in the Salish Sea (encompassing the Strait of Juan de Fuca, Puget Sound, and the Georgia Strait) is a major source of clams, oysters, and mussels in the United States and Canada. Plastic gear is necessary for the viability of many of these operations. During the past few years, shellfish farm permits issued in Washington State have been challenged on various bases that have included allegations that the plastic gear is releasing microplastics, commonly defined as particles less than 5 mm in diameter. Published survey data on sources of marine plastic debris demonstrate the very limited contribution of aquaculture gear. Both permits and industry codes of practice provide procedures to minimize loss of gear to the marine environment. Plastic gear is also designed specifically to maintain its integrity and not degrade in the marine environment. Plastic degradation is greatest on beaches with high UV exposure, whereas aquaculture gear is mostly underwater and/or covered by biofoulants. Available data for microplastics in water, sediment, and biota of the Salish Sea do not suggest significant release of microplastics from shellfish aquaculture operations. Integr Environ Assess Manag 2017;13:522-527. © 2017 SETAC. © 2017 SETAC.

  15. 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...

  16. Offshore Finfish Aquaculture in the United States: An Examination of Federal Laws That Could be Used to Address Environmental and Occupational Public Health Risks

    Directory of Open Access Journals (Sweden)

    Jillian P. Fry

    2014-11-01

    Full Text Available Half of the world’s edible seafood comes from aquaculture, and the United States (US government is working to develop an offshore finfish aquaculture industry in federal waters. To date, US aquaculture has largely been regulated at the state level, and creating an offshore aquaculture industry will require the development of a new regulatory structure. Some aquaculture practices involve hazardous working conditions and the use of veterinary drugs, agrochemicals, and questionable farming methods, which could raise environmental and occupational public health concerns if these methods are employed in the offshore finfish industry in the US. This policy analysis aims to inform public health professionals and other stakeholders in the policy debate regarding how offshore finfish aquaculture should be regulated in the US to protect human health; previous policy analyses on this topic have focused on environmental impacts. We identified 20 federal laws related to offshore finfish aquaculture, including 11 that are relevant to preventing, controlling, or monitoring potential public health risks. Given the novelty of the industry in the US, myriad relevant laws, and jurisdictional issues in an offshore setting, federal agencies need to work collaboratively and transparently to ensure that a comprehensive and functional regulatory structure is established that addresses the potential public health risks associated with this type of food production.

  17. Promoting Rural Income from Sustainable Aquaculture through ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... from Sustainable Aquaculture through Social Learning in Sri Lanka (CIFSRF) ... And, they will explore the role of women as community conduits for applying and ... Organization for Women in Science for the Developing World (OWSD), IDRC ...

  18. Selected Technology Issues in U.S. Aquaculture

    National Research Council Canada - National Science Library

    1995-01-01

    ...; little reached commercial markets. Although trout had been produced for food since the turn of the century, only with the advent of the catfish culture industry did commercial aquaculture gain visibility as a market force...

  19. Modeling and Eigenfrequency Analysis of Sound-Structure Interaction in a Rectangular Enclosure with Finite Element Method

    Directory of Open Access Journals (Sweden)

    Samira Mohamady

    2009-01-01

    Full Text Available Vibration of structures due to external sound is one of the main causes of interior noise in cavities like automobile, aircraft, and rotorcraft, which disturb the comfort of passengers. Accurate modelling of such phenomena is required in eigenfrequency analysis and in designing an active noise control system to reduce the interior noise. In this paper, the effect of periodic noise travelling into a rectangular enclosure is investigated with finite element method (FEM using COMSOL Multiphysics software. The periodic acoustic wave is generated by a point source outside the enclosure and propagated through the enclosure wall and excites an aluminium flexible panel clamped onto the enclosure. The behaviour of the transmission of sound into the cavity is investigated by computing the modal characteristics and the natural frequencies of the cavity. The simulation results are compared with previous analytical and experimental works for validation and an acceptable match between them were obtained.

  20. Antimicrobial resistance genes in marine bacteria and human uropathogenic Escherichia coli from a region of intensive aquaculture.

    Science.gov (United States)

    Tomova, Alexandra; Ivanova, Larisa; Buschmann, Alejandro H; Rioseco, Maria Luisa; Kalsi, Rajinder K; Godfrey, Henry P; Cabello, Felipe C

    2015-10-01

    Antimicrobials are heavily used in Chilean salmon aquaculture. We previously found significant differences in antimicrobial-resistant bacteria between sediments from an aquaculture and a non-aquaculture site. We now show that levels of antimicrobial resistance genes (ARG) are significantly higher in antimicrobial-selected marine bacteria than in unselected bacteria from these sites. While ARG in tetracycline- and florfenicol-selected bacteria from aquaculture and non-aquaculture sites were equally frequent, there were significantly more plasmid-mediated quinolone resistance genes per bacterium and significantly higher numbers of qnrB genes in quinolone-selected bacteria from the aquaculture site. Quinolone-resistant urinary Escherichia coli from patients in the Chilean aquacultural region were significantly enriched for qnrB (including a novel qnrB gene), qnrS, qnrA and aac(6')-1b, compared with isolates from New York City. Sequences of qnrA1, qnrB1 and qnrS1 in quinolone-resistant Chilean E. coli and Chilean marine bacteria were identical, suggesting horizontal gene transfer between antimicrobial-resistant marine bacteria and human pathogens. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. Ventilation of radioactive enclosures

    International Nuclear Information System (INIS)

    Caminade, F.; Laurent, H.

    1957-01-01

    Mechanical, physical and chemical manipulations on radioactive products must be carried out in properly ventilated enclosed places. The air extracted can only be discharged into the atmosphere after a correct filtration. The power of the ventilation systems is a function of the dimensions and purpose of the enclosure? The choice of types of filter is determined by the physical state and chemical nature of the radioactive materials to be manipulated. This study deals with the individual equipment of small installations: glove boxes, manipulation boxes with outside control and, if necessary, production chambers (maximum useful volume: 5 m 3 ). The performances of three types of 'ventilators', and the modifications provided by the addition of filters, are measured and compared. (author) [fr

  2. Pathogenic potentials of Aeromonas species isolated from aquaculture and abattoir environments.

    Science.gov (United States)

    Igbinosa, Isoken H; Beshiru, Abeni; Odjadjare, Emmanuel E; Ateba, Collins N; Igbinosa, Etinosa O

    2017-06-01

    The present study elucidated the presence of antibiotics resistance, virulence genes and biofilm potentials among Aeromonas species isolated from abattoir and aquaculture environments in Benin City, Nigeria. A total of 144 wastewater samples were obtained from two independent aquaculture and abattoir environments between May and October 2016. Aeromonas species were isolated on Glutamate Starch Phenol Red (GSP) agar and confirmed using API 20NE kits. Antimicrobial susceptibility profile of the isolates was carried out using standard disc diffusion assay while biofilm potentials were detected by the microtitre plate method and PCR technique was used to detect antibiotics resistance and virulence gene markers. Overall, 32 and 26 Aeromonas species were isolated from the abattoir and aquaculture environments respectively. Isolates from both environments were completely resistant (100%) to penicillin G, ertapenem and tetracycline; whereas aquaculture isolates exhibited absolute sensitivity (100%) towards cefepime. All the virulence gene markers (aerA, hlyA, alt, ast, laf, ascF-G, fla, lip, stx1, and stx2) investigated in this study (except laf) were detected in isolates from both environments. The laf genes were only detected in isolates from abattoir environments. Antibiotics resistant genes including pse, bla TEM and class 1 integron were detected in isolates from both environments. Majority of the isolates (53/58 91.4%) from both environments; demonstrated capacity for biofilm potential. The detection of antibiotic resistance and virulence gene markers as well as biofilm forming ability in Aeromonas species isolated from aquaculture and abattoir environments raise serious public health concern worthy of further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Humidity Build-Up in a Typical Electronic Enclosure Exposed to Cycling Conditions and Effect on Corrosion Reliability

    DEFF Research Database (Denmark)

    Conseil, Helene; Gudla, Visweswara Chakravarthy; Jellesen, Morten Stendahl

    2016-01-01

    The design of electronic device enclosures plays a major role in determining the humidity build-up inside the device as a response to the varying external humidity. Therefore, the corrosion reliability of electronic devices has direct connection to the enclosure design. This paper describes......, thermal mass, and port/opening size. The effect of the internal humidity build-up on corrosion reliability has been evaluated by measuring the leakage current (LC) on interdigitated test comb patterns, which are precontaminated with sodium chloride and placed inside the enclosure. The results showed...... that the exposure to cycling temperature causes significant change of internal water vapor concentration. The maximum value of humidity reached was a function of the opening size and the presence of thermal mass inside the enclosure. A pumping effect was observed due to cycling temperature, and the increase...

  4. Aquaculture et environnement: aspects réglementaires : journées d'études, Nantes, 6-7 octobre 1993

    National Research Council Canada - National Science Library

    1994-01-01

    ...) L'aquaculture in Italie; 6) L'aquaculture au sein de la Communaute economique europeenne; 7) Freshwater aquaculture in the United States, complying with environmental protection law and policy; 8...

  5. Aquaculture genomics, genetics and breeding in the United States: Current status, challenges, and priorities for future research

    Science.gov (United States)

    Advancing the production efficiency and profitability of aquaculture is dependent upon the ability to utilize a diverse array of genetic resources. The ultimate goals of aquaculture genomics, genetics and breeding research are to enhance aquaculture production efficiency, sustainability, product qua...

  6. Genomic approaches in aquaculture and fisheries

    DEFF Research Database (Denmark)

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

    2010-01-01

    . 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...

  7. REVIEW OF AQUACULTURAL PRODUCTION SYSTEM MODELS ...

    African Journals Online (AJOL)

    However, the complexity of an aquaculture system which result from multiple interactions makes it difficult to predict how the aquatic community will respond to changes with simple methods of analysis, especially if the methods address a single stressor at a time. These necessitated the development of numerous aquatic ...

  8. Fisheries And Aquaculture Resources And Their Interactions With Environment in Turkey

    Science.gov (United States)

    Deniz, H.

    2003-04-01

    Turkey, with 8333 km of coast line, 151 080 sq. km economic sea area, many rivers with 177 714 total length, nearly, 1 million ha of natural lakes, 500 000 ha of dam reservoirs has rich marine and inland aquatic resource potential. Despite of these large resources, Turkish fisheries has the characteristics of small-scale fisheries and in general it can be considered as coastal fisheries. There is also great potential for inland fisheries and aquaculture. Being in half closed position, these seas have different characteristics in respect of biological, physical, chemical and ecological points. In addition; Turkey has favourable geographic position between the Black Sea and Mediterranean Sea. Nevertheless, this potential seems not to be fully utilised and therefore fisheries is not a major sector in the economy. According to the statistics of the fisheries for 2000 published by the Turkish government, Turkey's total fisheries production was 582.376 tons. Total catch consists sea fish (441 690 tons, crustaceans and molluscs (18 831 tons), freshwater fish (42.824 tons) and aquaculture (79. 031 tons). The Ministry of Agriculture and Rural Affairs (MARA) is the Ministry responsible for the overall fisheries and aquaculture development, administration, regulation, promotion and technical assistance. In the past two decades, marine fish farming using net cages has developed in the coastal waters throughout Turkey. Such fish farming has allowed the production of large amounts of valuable fish and their supply to the internal and external markets on a regular basis. However, fish farming is sometimes fallowed by organic pollution of the water and bottom sediment in the vicinity of the cages. A comprehensive land and coastal planning survey of almost the whole coast of Turkey is currently being conducted. This master plan designates areas to be developed for forestry, agriculture, industry, urbanisation, environmentally protected areas, etc. The plan was undertaken before the

  9. Quality of antimicrobial products used in white leg shrimp (Litopenaeus vannamei) aquaculture in Northern Vietnam

    DEFF Research Database (Denmark)

    Tran, Kim Chi; Tran, Minh Phu; Phan, Thi Van

    2018-01-01

    Antimicrobials are important to treat diseases in aquaculture and the objective of this study was to evaluate the quality of antimicrobial products commonly used in white leg shrimp (Litopenaeus vannamei) aquaculture in Northern Vietnam. A total of 25 antimicrobial products were obtained from 20...... to strengthen diagnostic services, legislation and control of antimicrobial products in shrimp aquaculture and educate farmers on prudent antimicrobial use practices....

  10. New developments in recirculating aquaculture systems in Europe: a perspective on environmental sustainability

    NARCIS (Netherlands)

    Martins, C.I.; Eding, E.H.; Verdegem, M.C.J.; Heinsbroek, L.T.N.; Schneider, O.; Blancheton, J.P.; Roque dÓrbcastel, E.; Verreth, J.A.J.

    2010-01-01

    The dual objective of sustainable aquaculture, i.e., to produce food while sustaining natural resources is achieved only when production systems with a minimum ecological impact are used. Recirculating aquaculture systems (RASs) provide opportunities to reduce water usage and to improve waste

  11. Use of aquaculture ponds and other habitats by autumn migrating shorebirds along the lower Mississippi river.

    Science.gov (United States)

    Lehnen, Sarah E; Krementz, David G

    2013-08-01

    Populations of many shorebird species are declining; habitat loss and degradation are among the leading causes for these declines. Shorebirds use a variety of habitats along interior migratory routes including managed moist soil units, natural wetlands, sandbars, and agricultural lands such as harvested rice fields. Less well known is shorebird use of freshwater aquaculture facilities, such as commercial cat- and crayfish ponds. We compared shorebird habitat use at drained aquaculture ponds, moist soil units, agricultural areas, sandbars and other natural habitat, and a sewage treatment facility in the in the lower Mississippi River Alluvial Valley (LMAV) during autumn 2009. Six species: Least Sandpiper (Calidris minutilla), Killdeer (Charadrius vociferous), Semipalmated Sandpiper (Calidris pusilla), Pectoral Sandpiper (C. melanotos), Black-necked Stilt (Himantopus himantopus), and Lesser Yellowlegs (Tringa flavipes), accounted for 92 % of the 31,165 individuals observed. Sewage settling lagoons (83.4, 95 % confidence interval [CI] 25.3-141.5 birds/ha), drained aquaculture ponds (33.5, 95 % CI 22.4-44.6 birds/ha), and managed moist soil units on public lands (15.7, CI 11.2-20.3 birds/ha) had the highest estimated densities of shorebirds. The estimated 1,100 ha of drained aquaculture ponds available during autumn 2009 provided over half of the estimated requirement of 2,000 ha by the LMAV Joint Venture working group. However, because of the decline in the aquaculture industry, autumn shorebird habitats in the LMAV may be limited in the near future. Recognition of the current aquaculture habitat trends will be important to the future management activities of federal and state agencies. Should these aquaculture habitat trends continue, there may be a need for wildlife biologists to investigate other habitats that can be managed to offset the current and expected loss of aquaculture acreages. This study illustrates the potential for freshwater aquaculture to

  12. A history of fish vaccination: science-based disease prevention in aquaculture.

    Science.gov (United States)

    Gudding, Roar; Van Muiswinkel, Willem B

    2013-12-01

    Disease prevention and control are crucial in order to maintain a sustainable aquaculture, both economically and environmentally. Prophylactic measures based on stimulation of the immune system of the fish have been an effective measure for achieving this goal. Immunoprophylaxis has become an important part in the successful development of the fish-farming industry. The first vaccine for aquaculture, a vaccine for prevention of yersiniosis in salmonid fish, was licensed in USA in 1976. Since then the use of vaccines has expanded to new countries and new species simultaneous with the growth of the aquaculture industry. This paper gives an overview of the achievements in fish vaccinology with particular emphasis on immunoprophylaxis as a practical tool for a successful development of bioproduction of aquatic animals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Characteristics and environmental carrying capacities of coastal area in Yogyakarta Special Region for aquaculture

    Science.gov (United States)

    Triyatmo, B.; Rustadi; Priyono, S. B.

    2018-03-01

    The purpose of this study were to determine characteristics and environmental carrying capacities of coastal area in Yogyakarta Special Region for aquaculture. This study was conducted in 2015 by characterizing land and water dynamics, land use, and the suitability of coastal environments for aquaculture. Evaluation on the coastal environments suitability for aquaculture ponds was based on the landforms, soil properties, water quality and land. Selection of coastal locations for aquaculture development was based on the level of suitability of coastal environment. The results showed that the coastal in Kulon Progo and Bantul Regencies were characterized by sand dune and beach ridge with sandy soil texture, while in Gunungkidul Regency was characterized by limestone hill with rocky texture. Water sources of the coastal area were the sea, river, and ground water with the salinity of 31–37, 7–11, 7–31 ppt and pH of 7.4–8.4 7.0–8.2 and 7.4–9.9, respectively. The coastal lands were used for seasonal/annual planting, ponds, fish landing sites, tourism areas and conservation areas. The coastal carrying capacity was rather suitable for aquaculture, especially in the sandy soil area. Aquaculture in that area can be done intensively for shrimp (Litopenaeus vannamei), using biocrete (biological material) or plastic sheet.

  14. Seawater circulating system in an aquaculture laboratory

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Ingole, B.S.; Parulekar, A.H.

    The note gives an account, for the first time in India, of an Aquaculture Laboratory with open type seawater circulating system developed at the National Institute of Oceanography, Goa, India. Besides describing the details of the system...

  15. Enhancing monochromatic multipole emission by a subwavelength enclosure of degenerate Mie resonances

    KAUST Repository

    Zhao, Jiajun

    2017-07-06

    Sound emission is inefficient at low frequencies as limited by source size. This letter presents enhancing emission of monochromatic monopole and multipole sources by enclosing the source with a subwavelength circular enclosure filled of an anisotropic material of a low radial sound speed. The anisotropy is associated with an infinite tangential density along the azimuth. Numerical simulations show that emission gain is produced at frequencies surrounding degenerate Mie resonant frequencies of the enclosure, and meanwhile the radiation directivity pattern is well preserved. The degeneracy is theoretically analyzed. A realization of the material is suggested by using a space-coiling structure.

  16. Analysis of moisture transport between connected enclosures under a forced thermal gradient

    DEFF Research Database (Denmark)

    Staliulionis, Zygimantas; Joshy, Salil; Ambat, Rajan

    2016-01-01

    and humidity control solutions. While high fidelity CFD codes are too time consuming due to computational effort/time, the well-known Resistor-Capacitor (RC) approach has much lower calculation time and is more efficient to use in enclosures without too complex geometry in their interior. Thus, the objective...... of this paper is to build an in-house code based on the RC approach for simulating coupled heat and mass transport. The developed code is used for simulating moisture transport between two boxes/enclosures having different temperatures, connected with a tube of known geometry. It has also the capability...

  17. The Potential for Engineering Enhanced Functional-Feed Soybeans for Sustainable Aquaculture Feed.

    Science.gov (United States)

    Herman, Eliot M; Schmidt, Monica A

    2016-01-01

    Aquaculture is the most rapidly growing segment of global animal production that now surpasses wild-capture fisheries production and is continuing to grow 10% annually. Sustainable aquaculture needs to diminish, and progressively eliminate, its dependence on fishmeal-sourced feed from over-harvested fisheries. Sustainable aquafeed sources will need to be primarily of plant-origin. Soybean is currently the primary global vegetable-origin protein source for aquaculture. Direct exchange of soybean meal for fishmeal in aquafeed has resulted in reduced growth rates due in part to soybean's anti-nutritional proteins. To produce soybeans for use in aquaculture feeds a new conventional line has been bred termed Triple Null by stacking null alleles for the feed-relevant proteins Kunitz Trypsin Inhibitor, lectin, and P34 allergen. Triple Null is now being further enhanced as a platform to build additional transgene traits for vaccines, altered protein composition, and to produce high levels of β-carotene an intrinsic orange-colored aquafeed marker to distinguish the seeds from commodity beans and as the metabolic feedstock precursor of highly valued astaxanthin.

  18. Risks of Using Antifouling Biocides in Aquaculture

    Science.gov (United States)

    Guardiola, Francisco Antonio; Cuesta, Alberto; Meseguer, José; Esteban, Maria Angeles

    2012-01-01

    Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT). The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®), Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine), zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i) predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii) the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF) biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms. PMID:22408407

  19. Risks of Using Antifouling Biocides in Aquaculture

    Directory of Open Access Journals (Sweden)

    José Meseguer

    2012-02-01

    Full Text Available Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT. The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®, Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine, zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms.

  20. Sustainable aquaculture of Asian arowana--a review.

    Science.gov (United States)

    Medipally, S R; Yusoff, F M; Sharifhuddin, N; Shariff, M

    2016-07-01

    Asian arowana, Scleropages formosus is a highly valued aquarium fish in the world, particularly in Asian countries, and has been listed as one of the most highly endangered species. This is a freshwater, carnivorous, fairly large mouth breeding fish belonging to the family Osteoglossidae. Arowana can be found in different colour varieties such as green, red, silver and golden. Among these varieties, Malaysian golden is the most valuable fish and is endemic to the Krian riverine system, Malaysia. However, overexploitation, habitat change and pollution have caused a serious decline of this arowana variety. Recently, arowana aquaculture industry is expanding rapidly in Southeast Asian countries. However, difficulties in an accurate differentiation of sex and strains, causing imbalanced stocking ratios for optimum spawning, remain major obstacles in maximizing arowana production. In addition, problems in sustainable water sources of suitable quality and prevention of diseases need to be addressed. Recirculating aquaculture system (RAS) and bioremediation are two possible technologies that could be used to minimize pollution and ensure adequate high-quality water for arowana culture. In addition, the application of appropriate molecular markers for sex and strain identification is also an important strategy required for the improvement of captive breeding. This review discusses several issues such as the importance of arowana as an aquarium fish, its market demand, current problems in the arowana aquaculture industry and the possible technologies to enhance reproductive capacity and increase culture production. ?

  1. Nutrients' removal from aquaculture wastewater using the macroalgae Gracilaria birdiae

    Energy Technology Data Exchange (ETDEWEB)

    Marinho-Soriano, E.; Nunes, S.O.; Carneiro, M.A.A.; Pereira, D.C. [Universidade Federal do Rio Grande do Norte, Depto. de Oceanografia e Limnologia, Via Costeira, Praia de Mae Luiza, s/n, Natal, RN 59014-100 (Brazil)

    2009-02-15

    Intensive aquaculture releases large amount of nutrients into aquatic ecosystems and can lead to eutrophication of coastal waters. Studies conducted in aquaculture systems have demonstrated that the seaweeds are efficient in reducing nutrients and at the same time provides extra income, when species of economic importance are used. This study was conducted to evaluate whether Gracilaria birdiae could be cultivated efficiently for the production of useful algal biomass and removal of nutrients from shrimp pond effluents. The results obtained showed a gradual increase in biomass and relative growth rate (RGR) over the experimental period. Mean RGR between the weeks varied significantly (p < 0.01), reaching a maximum of 3.6 {+-} 0.35% d{sup -1} and a minimum of 1.6 {+-} 0.52% d{sup -1}. The mean for the whole period was 2.6% d{sup -1}. The biofiltration capacity of G. birdiae was confirmed by the significantly reduced concentration of the three nutrients analyzed (PO{sub 4}{sup 3-}, NH{sub 4}{sup +} and NO{sub 3}{sup -}) over the study period. The concentration of PO{sub 4}{sup 3-} decreased by 93.5%, NH{sub 4}{sup +} by 34% and NO{sub 3}{sup -} by 100% after the 4-week experimental period. The results obtained in this study indicated that G. birdiae can be used in aquaculture systems as a biofilter. In addition, the macroalgae biomass produced offers alternative source of raw material for the extraction of the phycocolloid agar, human food and animal feed. (author)

  2. Mathematical modelling of moisture transport into an electronic enclosure under non-isothermal conditions

    DEFF Research Database (Denmark)

    Staliulionis, Ž.; Mohanty, S.; Jabbari, Mahmoud

    2017-01-01

    In contrast to high fidelity CFD codes which require higher computational effort/time, the well-known Resistor-Capacitor (RC) approach requires much lower calculation time, but has a lower resolution of the geometrical arrangement. Therefore, for enclosures without too complex geometry in their i......In contrast to high fidelity CFD codes which require higher computational effort/time, the well-known Resistor-Capacitor (RC) approach requires much lower calculation time, but has a lower resolution of the geometrical arrangement. Therefore, for enclosures without too complex geometry...

  3. Application of physics technology in aquaculture

    International Nuclear Information System (INIS)

    Bai Yaxiang; Hu Yucai; Yang Guijuan

    2002-01-01

    Experiments show that after hydrobiology stimulation by a certain dosage of a physical field such as electromagnetic, laser, or neutron irradiation, hydorbiological activity can be improved, and consequently yield and quality enhanced. Recent advances in the application of physical fields in aquaculture are summarized, and prospects for future developments presented

  4. biotechnology in aquaculture: prospects and challenges

    African Journals Online (AJOL)

    JOSEPH

    Fish farming is the world's fastest-growing sector of agricultural business. ... history of application: e.g. fertilization of ponds to increase feed availability. ... significant advances in the genetic improvement of Tilapia used in aquaculture in recent ... Vaccines: Modern technology is also of great value in the field of vaccines and.

  5. Social Dynamics Shaping the Diffusion of Sustainable Aquaculture Innovations in the Solomon Islands

    Directory of Open Access Journals (Sweden)

    Jessica Blythe

    2017-01-01

    Full Text Available Sustainably feeding the world’s growing population represents one of our most significant challenges. Aquaculture is well positioned to make contributions towards this challenge. Yet, the translation of aquaculture production innovations into benefits for rural communities is constrained by a limited understanding of the social dynamics that influence the adoption of new agricultural practices. In this paper, we investigate the factors that shape the spread of small-scale tilapia aquaculture through rural Solomon Islands. Based on diffusion of innovation theory, we focus on three potentially influential factors: (i socio-economic characteristics of adopters; (ii the role of opinion leaders; and (iii characteristics of the innovation. We find that farmers who were wealthier, older, and had more diverse livelihoods were most likely to be adopters. Opinion leaders facilitated the adoption of tilapia aquaculture, but lacked the capacity to provide fundamental knowledge necessary to realize its potential benefits to food security. The paper argues for more explicit attention to the poorest households and makes the case for a deeper engagement with the broader social and institutional contexts that shape the adoption process. Aquaculture interventions that account for these social dynamics are critical for translating production innovations into sustainable benefits to rural communities.

  6. Free convective condensation in a vertical enclosure

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R.J.; Peterson, P.F. [Univ. of California, Berkeley, CA (United States); Corradini, M.L.; Pernsteiner, A.P. [Univ. of Wisconsin, Madison, WI (United States)

    1995-09-01

    Free convective condensation in a vertical enclosure was studied numerically and the results were compared with experiments. In both the numerical and experimental investigations, mist formation was observed to occur near the cooling wall, with significant droplet concentrations in the bulk. Large recirculation cells near the end of the condensing section were generated as the heavy noncondensing gas collecting near the cooling wall was accelerated downward. Near the top of the enclosure the recirculation cells became weaker and smaller than those below, ultimately disappearing near the top of the condenser. In the experiment the mist density was seen to be highest near the wall and at the bottom of the condensing section, whereas the numerical model predicted a much more uniform distribution. The model used to describe the formation of mist was based on a Modified Critical Saturation Model (MCSM), which allows mist to be generated once the vapor pressure exceeds a critical value. Equilibrium, nonequilibrium, and MCSM calculations were preformed, showing the experimental results to lie somewhere in between the equilibrium and nonequilibrium predictions of the numerical model. A single adjustable constant (indicating the degree to which equilibrium is achieved) is used in the model in order to match the experimental results.

  7. Increasing pressure on freshwater resources due to terrestrial feed ingredients for aquaculture production

    NARCIS (Netherlands)

    Pahlow, G.; Oel, van P.R.; Mekonnen, M.M.; Hoekstra, A.Y.

    2015-01-01

    As aquaculture becomes more important for feeding the growing world population, so too do the required natural resources needed to produce aquaculture feed. While there is potential to replace fish meal and fish oil with terrestrial feed ingredients, it is important to understand both the positive

  8. Transient characteristics of thermal energy storage in an enclosure packed with MEPCM particles

    International Nuclear Information System (INIS)

    Siao, Yong-Hao; Yan, Wei-Mon; Lai, Chi-Ming

    2015-01-01

    The heat transfer characteristics of phase change materials have been of continuing interest of research due to various potential technical applications, such as the latent-heat thermal energy storage, thermal protection, as well as active/passive electronic cooling. In this work, the transient characteristics of thermal energy storage in a partitioned enclosure filled with microencapsulated phase change material (MEPCM) particles were investigated experimentally and numerically. To examine the different melting temperature effects, two different MEPCM particles are tested. The core phase change materials of the MEPCM are n-octadecane with melting temperature about T M  = 28 °C and 37 °C. The enclosure is partitioned and is differentially heated by the two horizontal isothermal surfaces, while the other vertical surfaces are considered thermally insulated. The studies have been undertaken for five sets of the hot and cold wall temperatures imposed across the enclosure. The consequents show that the numerical results are in agreement with the measured data. At the initial transient, the net energy storage in enclosure, Q net , increases with the time Fo. Finally, the Q net approaches quickly the steady state for the case with a higher temperature difference of T h  − T c . Additionally, higher dimensionless accumulated energy through the hot wall Q h and cold wall Q c is found for a case with higher hot wall temperature T h

  9. Performance Study of Ceramic Filter Module in Recirculated Aquaculture System (RAS)

    Science.gov (United States)

    Ng, L. Y.; Ng, C. Y.

    2017-06-01

    The growth of world population has led to significant increase in seafood demand over the world. Aquaculture has been widely accepted by many countries to increase the seafood production owing to the decline of natural seafood resources. The aquaculture productivity, however, is directly linked to the pond water quality. In this study, attempts were made to employ ceramic micro-filter to improve the pond water quality through filtration processes. There were two batches of filtration processes, short term (1 hour) and long term (48 hours). Significant improvements on real pond water quality were recorded through the short term microfiltration process, which reduced turbidity (96%), total suspended solids (TSS) (80%), biochemical oxygen demand (BOD) (72%), chemical oxygen demand (COD) (55%), ammonia (60%), nitrate (96%) and phosphorus (83%). The long term filtration process also showed high efficiency in the removal of solid particle and organic matters. The results showed that all of the parameters were successfully reduced to acceptable ranges (turbidityfiltered pond water. Current study showed that the microfiltration using ceramic micro-filter has high potential to be used in recirculating aquaculture system throughout the aquaculture activities in order to maintain the pond water quality, thus, increase the survival rate of cultured species.

  10. Predicting shifting sustainability tradeoffs in marine finfish aquaculture under climate change.

    Science.gov (United States)

    Sarà, Gianluca; Gouhier, Tarik C; Brigolin, Daniele; Porporato, Erika M D; Mangano, M Cristina; Mirto, Simone; Mazzola, Antonio; Pastres, Roberto

    2018-05-03

    Defining sustainability goals is a crucial but difficult task because it often involves the quantification of multiple interrelated and sometimes conflicting components. This complexity may be exacerbated by climate change, which will increase environmental vulnerability in aquaculture and potentially compromise the ability to meet the needs of a growing human population. Here, we developed an approach to inform sustainable aquaculture by quantifying spatio-temporal shifts in critical trade-offs between environmental costs and benefits using the time to reach the commercial size as a possible proxy of economic implications of aquaculture under climate change. Our results indicate that optimizing aquaculture practices by minimizing impact (this study considers as impact a benthic carbon deposition ≥ 1 gC m -2 d -1 ) will become increasingly difficult under climate change. Moreover, an increasing temperature will produce a poleward shift in sustainability trade-offs. These findings suggest that future sustainable management strategies and plans will need to account for the effects of climate change across scales. Overall, our results highlight the importance of integrating environmental factors in order to sustainably manage critical natural resources under shifting climatic conditions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Enhancement of existing geothermal resource utilization by cascading to intensive aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Zachritz, W.H., II; Polka, R.; Schoenmackers

    1996-04-01

    A demonstration high rate aquaculture production system utilizing a cascaded geothermal resource was designed, constructed and operated to fulfill the objectives of this project. Analysis of the energy and water balances for the system indicated that the addition of an Aquaculture Facility expanded the use of the existing resource. This expanded use in no way affected the up- stream processes. Analysis of the system`s energy and water requirements indicated that the present resource was under-utilized and could be expanded. Energy requirements appeared more limiting than water use, but the existing system could be expanded to a culture volume of 72,000 gal. This system would have a potential production capacity of 93,600 lb/yr with a potential market value of $280,00/yr. Based on the results of this study, the heat remaining in the geothermal fluid from one square foot of operating greenhouse is sufficient to support six gallons of culture water for a high density aquaculture facility. Thus, the over 1.5M ft{sup 2} of existing greenhouse space in New Mexico, has the potential to create an aquaculture industry of nearly 9M gal. This translates to an annual production potential of 11.7M lb with a market value of $35.lM.

  12. Aquaculture practices and the coastal marine environment

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Ansari, Z.A.; Sreepada, R.A.

    . The size of the industry which is now beginning to emerge, the scale of its individual production units, raise questions concerning the high input rate of feed and chemical and a correspondingly high production of wastes. In intensive aquaculture system...

  13. Furthering knowledge of seaweed growth and development to facilitate sustainable aquaculture.

    Science.gov (United States)

    Charrier, Bénédicte; Abreu, Maria Helena; Araujo, Rita; Bruhn, Annette; Coates, Juliet C; De Clerck, Olivier; Katsaros, Christos; Robaina, Rafael R; Wichard, Thomas

    2017-12-01

    Macroalgae (seaweeds) are the subject of increasing interest for their potential as a source of valuable, sustainable biomass in the food, feed, chemical and pharmaceutical industries. Compared with microalgae, the pace of knowledge acquisition in seaweeds is slower despite the availability of whole-genome sequences and model organisms for the major seaweed groups. This is partly a consequence of specific hurdles related to the large size of these organisms and their slow growth. As a result, this basic scientific field is falling behind, despite the societal and economic importance of these organisms. Here, we argue that sustainable management of seaweed aquaculture requires fundamental understanding of the underlying biological mechanisms controlling macroalgal life cycles - from the production of germ cells to the growth and fertility of the adult organisms - using diverse approaches requiring a broad range of technological tools. This Viewpoint highlights several examples of basic research on macroalgal developmental biology that could enable the step-changes which are required to adequately meet the demands of the aquaculture sector. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  14. Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures

    International Nuclear Information System (INIS)

    Gress, J.; Silva, E.B. da; Oliveira, L.M. de; Zhao, Di; Anderson, G.; Heard, D.; Stuchal, L.D.; Ma, L.Q.

    2016-01-01

    Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0–110 mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46 mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6–111 μg/100 cm 2 , typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22–7.8 μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37 mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. - Highlights: • Daily inorganic As dose from zoo animal foods was 0.22–7.8 μg/kg bw/day. • Total As concentrations in soils of zoo animal enclosures were 1.0–110 mg/kg. • Endangered zoo animals live in soils with As above USEPA Eco-SSLs for avian and mammal species. • Dislodgeable As on CCA-wood beams where primates sit was 4.6–111 μg/100 cm 2 . • Marmoset hair had 6.37 mg/kg As compared to a reference value of 0.21 mg/kg.

  15. Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures

    Energy Technology Data Exchange (ETDEWEB)

    Gress, J. [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 201146 (China); Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States); Silva, E.B. da; Oliveira, L.M. de [Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States); Zhao, Di [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 201146 (China); Anderson, G. [Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Heard, D. [Department of Small Animal Clinical Sciences, University of Florida, Gainesville, FL 32610 (United States); Stuchal, L.D. [Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611 (United States); Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32611 (United States); Ma, L.Q., E-mail: lqma@ufl.edu [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 201146 (China); Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States)

    2016-05-01

    Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0–110 mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46 mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6–111 μg/100 cm{sup 2}, typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22–7.8 μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37 mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. - Highlights: • Daily inorganic As dose from zoo animal foods was 0.22–7.8 μg/kg bw/day. • Total As concentrations in soils of zoo animal enclosures were 1.0–110 mg/kg. • Endangered zoo animals live in soils with As above USEPA Eco-SSLs for avian and mammal species. • Dislodgeable As on CCA-wood beams where primates sit was 4.6–111 μg/100 cm{sup 2}. • Marmoset hair had 6.37 mg/kg As compared to a reference value of 0.21 mg/kg.

  16. Behavioral observations of the endangered Rio Grande silvery minnow in a conservation aquaculture facility

    Directory of Open Access Journals (Sweden)

    Tave Douglas

    2018-03-01

    Full Text Available A major reason why conservation aquaculture is needed to improve the success of aquaculture-assisted fisheries is that traditional production aquaculture produces fish with mal-adaptive behaviors. These behaviors can be produced via domestication and culture techniques, and preventing these mal-adaptive behaviors requires integrating improvements in genetic management and culture protocols. The genetic protocols needed to minimize hatchery-induced genetic changes have received considerable attention, but changing the way fish are raised has received less effort. Conservation aquaculture cultures fish in environments that resemble their native habitats so that when stocked, they behave like wild fish rather than hatchery fish. A purpose built-conservation aquaculture facility can also be used to learn about a species’ behavior and how it reacts to changes in the environment, something which can be difficult or expensive to study in the wild. These observations can then be used to help direct both propagation and recovery management. This paper provides the rationale for why genetic management, culture systems, and management practices need to be altered to produce fish that are behaviorally similar to wild fish for aquaculture-assisted fisheries programs. It then provides a description of some of the behaviors of the endangered Rio Grande silvery minnow Hybognathus amarus that were observed at the Los Lunas Silvery Minnow Refugium, a purpose-built conservation aquaculture facility, and explains how some of these behaviors can be used in culture and recovery management. Behaviors described are: schooling; predator avoidance; feeding behavior; use of vegetation for cover and predator avoidance; habitat use by bottom substrate; location in the water column; upstream movement via a fish ladder; movement upstream in a high-velocity channel; response to changes in water level; spawning behavior; seine avoidance; and Kaah-chee-nyee Srkaash, a behavior

  17. Aquaculture and environmental protection

    Energy Technology Data Exchange (ETDEWEB)

    Leclerc, J

    1977-01-01

    Aquaculture may end malnutrition; its output will increase from several million tons to more than 60 million ton/yr by the end of the century. A project aimed at developing the culture of mussels and oysters at the Magdalen Islands in the St. Lawrence Gulf is described. Biological and institutional problems, and obstacles to development are discussed. The key idea is to propose forms of cultivation that can occur in complete submersion below the level of the ice. (5 diagrams, 2 maps, 2 photos)

  18. Natural convection of Al2O3-water nanofluid in a wavy enclosure

    Science.gov (United States)

    Leonard, Mitchell; Mozumder, Aloke K.; Mahmud, Shohel; Das, Prodip K.

    2017-06-01

    Natural convection heat transfer and fluid flow inside enclosures filled with fluids, such as air, water or oil, have been extensively analysed for thermal enhancement and optimisation due to their applications in many engineering problems, including solar collectors, electronic cooling, lubrication technologies, food processing and nuclear reactors. In comparison, little effort has been given to the problem of natural convection inside enclosures filled with nanofluids, while the addition of nanoparticles into a fluid base to alter thermal properties can be a feasible solution for many heat transfer problems. In this study, the problem of natural convection heat transfer and fluid flow inside a wavy enclosure filled with Al2O3-water nanofluid is investigated numerically using ANSYS-FLUENT. The effects of surface waviness and aspect ratio of the wavy enclosure on the heat transfer and fluid flow are analysed for various concentrations of Al2O3 nanoparticles in water. Flow fields and temperature fields are investigated and heat transfer rate is examined for different values of Rayleigh number. Results show that heat transfer within the enclosure can be enhanced by increasing surface waviness, aspect ratio or nanoparticles volume fraction. Changes in surface waviness have little effect on the heat transfer rate at low Rayleigh numbers, but when Ra ≥ 105 heat transfer increases with the increase of surface waviness from zero to higher values. Increasing the aspect ratio causes an increase in heat transfer rate, as the Rayleigh number increases the effect of changing aspect ratio is more apparent with the greatest heat transfer enhancement seen at higher Rayleigh numbers. Nanoparticles volume fraction has a little effect on the average Nusselt number at lower Rayleigh numbers when Ra ≥ 105 average Nusselt number increases with the increase of volume fraction. These findings provide insight into the heat transfer effects of using Al2O3-water nanofluid as a heat

  19. The disposal and reparation of radio-active enclosures

    International Nuclear Information System (INIS)

    Boutot, P.

    1964-01-01

    The dismantling of active installations with a view to repairing them or disposing of them is an exceptional operation which tends nevertheless to become more frequent as the materials age technically or mechanically. The author describes, after two years experience, the peculiarities of the method for dismantling which is carried out inside sealed enclosures after the contamination has been fixed. (author) [fr

  20. Development of a European resource on the origins of pathogens of aquaculture: The Europa Project

    DEFF Research Database (Denmark)

    Snow, M.; Barja, J.; Colquhoun, D.

    2004-01-01

    This workshop described the EUROPA project, an EU-funded program aimed at creating a web-based database of molecular sequence data-sets related to significant pathogens of aquaculture. The project aims to focus the efforts of fish health researchers into generating large, evolving and readily ava...

  1. Species selection for smallholder aquaculture

    OpenAIRE

    Brummett, R.E.

    1996-01-01

    Systems for selection of species for smallholder aquaculture are presented. These are: food fits; management decisions; and economic criteria. Food fits suggests categorizing pond food resources into a few categories based loosely on the instrinsic traits of food which effect their selectivity by predators. Using management decision techniques, potential polycultures might also be compared with each other and with monoculture. Under economic criteria (and for species known in local markets), ...

  2. A Needs Assessment of Aquaculture Extension Agents, Specialists, and Program Administrators in Extension Programming

    Science.gov (United States)

    Schwarz, Michael H.; Gibson, Jerry

    2010-01-01

    The study reported here identified continuing education and training needs of aquaculture Extension agents, specialists, and program administrators in 10 competency areas relating to the need for continuing education or training. Fourteen resources on the AquaNIC Web site were also evaluated, as was the efficacy of the AQUA-EXT listserv. Data were…

  3. Some comments on the hydrogen atom in a spherical enclosure

    International Nuclear Information System (INIS)

    Aguilera-Navarro, V.C.; Koo, E.L.; Zimerman, A.H.

    1980-01-01

    Some properties of the ground state energy solutions for the hydrogen atom in a spherical enclosure are discussed. The application of the many-point Pade approximants to this kind of systems inside a box is consider also. (Author) [pt

  4. Transfer of toxic and radioactive materials to and from a work enclosure

    International Nuclear Information System (INIS)

    Hackney, S.

    1980-01-01

    Apparatus for transfer of toxic and radioactive materials between a work enclosure, e.g. a glove box, and a container for storing and transporting the materials comprises a 'double-cover' through which materials are moved. A port in the enclosure is closed by a first cover and the container is closed by a second cover. During transfer, the covers are connected together and the space between the covers is swept by an air stream supplied by a pipe to prevent ingress and deposition of toxic or radioactive material on the facing surfaces of the cover which are subsequently exposed to the environment on separation of the covers. (author)

  5. Agonistic behaviour in juvenile southern rock lobster, Jasus edwardsii (Decapoda, Palinuridae: implications for developing aquaculture

    Directory of Open Access Journals (Sweden)

    Chris Carter

    2014-11-01

    Full Text Available The Southern rock lobster, Jasus edwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasus edwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11, avoidance (6 and others (12. Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture.

  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. 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...

  8. Bivalve aquaculture-environment interactions in the context of climate change.

    Science.gov (United States)

    Filgueira, Ramón; Guyondet, Thomas; Comeau, Luc A; Tremblay, Réjean

    2016-12-01

    Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom-up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve-phytoplankton trophic interaction, which can range from a bottom-up control triggered by ammonia excretion to a top-down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top-down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is

  9. High rabbit abundance proves detrimental to the population growth rate in European rabbit (Oryctolagus cuniculus L. extensive breeding enclosures

    Directory of Open Access Journals (Sweden)

    L. Ruiz-Aizpurua

    2014-09-01

    Full Text Available The European rabbit (Oryctolagus cuniculus L. is a key prey species in Mediterranean ecosystems that has declined in its natural ranges as a result of diseases and loss of habitat. This situation has led to the production of wild rabbits in enclosures in which they can acclimate and breed. The efficiency of these enclosures as extensive breeding systems is defined by their population growth rate (PGR. The aim of this study is to analyse the effect of rabbit abundance on the PGR. This has been done by creating general linear models to explain autumn and spring PGR with the use of rabbit abundance estimates, enclosure size, aerial predation and previous PGR as possible explanatory variables. Rabbit abundance and enclosure size negatively affected the autumn PGR, while only rabbit abundance affected the spring PGR in the best-fit models. It is suggested that maintaining rabbit densities at fewer than 30 rabbits per hectare might help to optimise the efficiency inside enclosures.

  10. 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....... Fish performed similarly in all treatments. Preliminary screening of trout gills did not reveal any pathological changes related to microscreen filtration and the resulting water quality. Biofilter performance was also unaffected, with 0′-order nitrification rates (k0a) being equivalent for all twelve...

  11. Using the H-index to assess disease priorities for salmon aquaculture.

    Science.gov (United States)

    Murray, Alexander G; Wardeh, Maya; McIntyre, K Marie

    2016-04-01

    Atlantic salmon's (Salmo salar) annual aquaculture production exceeds 2M tonnes globally, and for the UK forms the largest single food export. However, aquaculture production is negatively affected by a range of different diseases and parasites. Effort to control pathogens should be focused on those which are most "important" to aquaculture. It is difficult to specify what makes a pathogen important; this is particularly true in the aquatic sector where data capture systems are less developed than for human or terrestrial animal diseases. Mortality levels might be one indicator, but these can cause a range of different problems such as persistent endemic losses, occasional large epidemics or control/treatment costs. Economic and multi-criteria decision methods can incorporate this range of impacts, however these have not been consistently applied to aquaculture and the quantity and quality of data required is large, so their potential for comparing aquatic pathogens is currently limited. A method that has been developed and applied to both human and terrestrial animal diseases is the analysis of published scientific literature using the H-index method. We applied this method to salmon pathogens using Web of Science searches for 23 pathogens. The top 3 H-indices were obtained for: sea lice, furunculosis, and infectious salmon anaemia; post 2000, Amoebic Gill Disease (AGD) replaced furunculosis. The number of publications per year describing bacterial disease declined significantly, while those for viruses and sea lice increased significantly. This reflects effective bacterial control by vaccination, while problems related to viruses and sea lice have increased. H-indices by country reflected different national concerns (e.g. AGD ranked top for Australia). Averaged national H-indices for salmon diseases tend to increase with log of salmon production; countries with H-Indices significantly below the trend line have suffered particularly large disease losses. The H

  12. 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.

  13. 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. © 2013.

  14. 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...

  15. Energy and economic analysis of a building enclosure outfitted with a phase change material board (PCMB)

    International Nuclear Information System (INIS)

    Sun, Xiaoqin; Zhang, Quan; Medina, Mario A.; Lee, Kyoung Ok

    2014-01-01

    Highlights: • Phase change material boards (PCMBs) were simulated in building enclosures. • Energy and economic savings for these buildings were estimated. • The buildings were located in five cities with different climatic conditions. • The energy savings ratio was 100% when a cold energy source was used. • A mean electricity savings ratio of 13.1% was obtained. - Abstract: This paper presents energy and economic analyses related to the application of phase change materials boards (PCMBs) in building enclosures during the cooling season. A heat transfer model was developed, which was implemented via a computer program. Simulations were carried out using weather data files from five cities located in five different climate regions in China. Energy savings from using a natural cold source (e.g., outdoor air) and electricity savings from a reduction in electricity by air conditioning systems were evaluated. The energy savings ratio (ESR) and simple payback period (SPP) were used to assess the application of PCMBs in building enclosures. The selection of optimum phase transition temperatures for the PCMs for the various climates was made using indoor and outdoor air temperatures, as well as SPP. For space cooling purposes, it was suggested that phase transition temperatures should be at least 3 °C higher than the mean outdoor air temperature. Simple payback period suggested the possibility of the cost effective use of PCMBs in occupied buildings for moderate temperature climates

  16. Impact of selective breeding on European aquaculture

    NARCIS (Netherlands)

    Janssen, K.; Chavanne, H.; Berentsen, P.; Komen, H.

    2017-01-01

    Objectives of this study were to determine the combined market share of breeding companies in aquaculture production in Europe, to describe the main characteristics of breeding companies and their programs, and to provide per species estimates on cumulative genetic gain in growth performance.

  17. 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

    Directory of Open Access Journals (Sweden)

    Serbulov Alexey

    2012-01-01

    Full Text Available 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 Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

  18. Natural convection heat transfer from a horizontal wavy surface in a porous enclosure

    International Nuclear Information System (INIS)

    Murthy, P.V.S.N.; Kumar, B.V.R.; Singh, P.

    1997-01-01

    The effect of surface undulations on the natural convection heat transfer from an isothermal surface in a Darcian fluid-saturated porous enclosure has been numerically analyzed using the finite element method on a graded nonuniform mesh system. The flow-driving Rayleigh number Ra together with the geometrical parameters of wave amplitude a, wave phase φ, and the number of waves N considered in the horizontal dimension of the cavity are found to influence the flow and heat transfer process in the enclosure. For Ra around 50 and above, the phenomenon of flow separation and reattachment is noticed on the walls of the enclosure. A periodic shift in the reattachment point from the bottom wall to the adjacent walls in the clockwise direction, leading to the manifestation of cycles of unicellular and bicellular clockwise and counterclockwise flows, is observed, with the phase varying between 0 degree and 350 degree. The counterflow in the secondary circulation zone is intensified with the increase in the value of Ra. The counterflow on the wavy wall hinders the heat transfer into the system. An increase in either wave amplitude or the number of waves considered per unit length decreases the global heat flux into the system. Only marginal changes in global heat flux are noticed with increasing Ra. On the whole, the comparison of global heat flux results in the wavy wall case with those of the horizontal flat wall case shows that, in a porous enclosure, the wavy wall reduces the heat transfer into the system

  19. Interactions of aquaculture, marine coastal ecosystems, and near-shore waters: A bibliography. Bibliographies and literature of agriculture (Final)

    International Nuclear Information System (INIS)

    Hanfman, D.T.; Coleman, D.E.; Tibbitt, S.J.

    1991-01-01

    The bibliography contains selected literature citations on the interactions of aquaculture and marine coastal ecosystems. The focus is on aquaculture effluents and their impact on marine coastal ecosystems and waterways as well as the impact of pollutants on aquaculture development. Factors affecting these issues include domestic and industrial wastes, thermal discharges, acid rain, heavy metals, oil spills, and microbial contamination of marine waters and aquatic species. Coastal zone management, environmenal impact of aquaculture, and water quality issues are also included in the bibliography

  20. An agro-ecological evaluation of aquaculture integration into farming systems of the Mekong Delta

    NARCIS (Netherlands)

    Phong, L.T.; Dam, van A.A.; Udo, H.M.J.; Mensvoort, van M.E.F.; Tri, L.Q.; Steenstra, F.A.; Zijpp, van der A.J.

    2010-01-01

    This study compared ecological sustainability of Integrated Agriculture-Aquaculture (IAA) systems with different forms and intensity of aquaculture integration in the Mekong Delta of Vietnam: orchard-based and low-input fish (O-LF); rice-based and medium-input fish (R-MF); and rice-based and

  1. A location procedure for sound sources in reactor-technical enclosures

    International Nuclear Information System (INIS)

    Hamann, D.

    1982-07-01

    A passive method requiring one detector only has been developed for the location of sound emitting faults in nuclear power plant components. It is adapted for use in a frequency range the wavelength of which is of the same order of magnitude as characteristic dimensions of the considered enclosure. The location is performed in the following way: (1) For a fixed detector position the Auto Power Spectral Density (APSD) of the source to be located is measured. (2) For this detector position the APSD is calculated for the potential source locations. For this, the free-field APSD as well as the acoustic normal modes of the enclosure are necessary. (3) The measured APSD is compared with the theoretically obtained APSD's. (4) That APSD is determined which is most similar to the measured APSD, and consequently an information about the unknown source position is got. (author)

  2. The influence of socio cultural dynamics on convergence communication of aquaculture agribusiness actors

    Science.gov (United States)

    Oktavia, Y.

    2018-03-01

    This research aims to: (1) Analyze the level of socio-cultural dynamics of agibusiness aquaculture actors. (2) Analyze the influence of socio-cultural dynamics on convergence communication of capacity development of aquaculture agribusiness actors.Data was collected by questionnaire and interview of group members on agribusiness. Data analyze was done by descriptive and inferential statistics with using SEM method. The result of descriptive statistics on 284 agribusiness members showed that: Socio-cultural dynamics of agibusiness aquaculture actors was in low category, as shown by lack of the role of customary institutions and quality of local leadership.The communication convergence is significantly and positively influenced by the communication behavior of agribusiness actors in access information.

  3. GAM-HEAT -- a computer code to compute heat transfer in complex enclosures

    International Nuclear Information System (INIS)

    Cooper, R.E.; Taylor, J.R.; Kielpinski, A.L.; Steimke, J.L.

    1991-02-01

    The GAM-HEAT code was developed for heat transfer analyses associated with postulated Double Ended Guillotine Break Loss Of Coolant Accidents (DEGB LOCA) resulting in a drained reactor vessel. In these analyses the gamma radiation resulting from fission product decay constitutes the primary source of energy as a function of time. This energy is deposited into the various reactor components and is re- radiated as thermal energy. The code accounts for all radiant heat exchanges within and leaving the reactor enclosure. The SRS reactors constitute complex radiant exchange enclosures since there are many assemblies of various types within the primary enclosure and most of the assemblies themselves constitute enclosures. GAM-HEAT accounts for this complexity by processing externally generated view factors and connectivity matrices, and also accounts for convective, conductive, and advective heat exchanges. The code is applicable for many situations involving heat exchange between surfaces within a radiatively passive medium. The GAM-HEAT code has been exercised extensively for computing transient temperatures in SRS reactors with specific charges and control components. Results from these computations have been used to establish the need for and to evaluate hardware modifications designed to mitigate results of postulated accident scenarios, and to assist in the specification of safe reactor operating power limits. The code utilizes temperature dependence on material properties. The efficiency of the code has been enhanced by the use of an iterative equation solver. Verification of the code to date consists of comparisons with parallel efforts at Los Alamos National Laboratory and with similar efforts at Westinghouse Science and Technology Center in Pittsburgh, PA, and benchmarked using problems with known analytical or iterated solutions. All comparisons and tests yield results that indicate the GAM-HEAT code performs as intended

  4. A Review - Biology, Aquaculture and Medical Use of Seahorse, Hippocampus spp

    OpenAIRE

    Yuan Yuan Zhang; Bo-Mi Ryu; Zhong-Ji Qian

    2017-01-01

    Seahorse has been used as medicine in Asian countries such as China, Korea, Japan and Vietnam for thousands of years. However, in western countries, the ecology of seahorse has been a focus of attention of many researchers for years. The seahorse aquaculture is popular with aqua farm worldwide for the sake of the increased demand of seahorse. This review described the biology, aquaculture and medical use of seahorse. To present the ecology and highlight the role of seahorse in traditional med...

  5. Organic matter decomposition in simulated aquaculture ponds

    NARCIS (Netherlands)

    Torres Beristain, B.

    2005-01-01

    Different kinds of organic and inorganic compounds (e.g. formulated food, manures, fertilizers) are added to aquaculture ponds to increase fish production. However, a large part of these inputs are not utilized by the fish and are decomposed inside the pond. The microbiological decomposition of the

  6. Production of cobia in recirculating aquaculture systems

    Science.gov (United States)

    Interest in cobia Rachycentron canadum aquaculture in the US has increased greatly in the last decade due to their excellent consumer appeal, extremely rapid growth rates, and the observed success of rearing this species in Taiwan and other southeastern Asian countries. Because most cobia are grown...

  7. Numerical Study of Natural Convection within a Wavy Enclosure Using Meshfree Approach: Effect of Corner Heating

    Directory of Open Access Journals (Sweden)

    Sonam Singh

    2014-01-01

    Full Text Available This paper presents a numerical study of natural convection within a wavy enclosure heated via corner heating. The considered enclosure is a square enclosure with left wavy side wall. The vertical wavy wall of the enclosure and both of the corner heaters are maintained at constant temperature, Tc and Th, respectively, with Th>Tc while the remaining horizontal, bottom, top and side walls are insulated. A penalty element-free Galerkin approach with reduced gauss integration scheme for penalty terms is used to solve momentum and energy equations over the complex domain with wide range of parameters, namely, Rayleigh number (Ra, Prandtl number (Pr, and range of heaters in the x- and y-direction. Numerical results are represented in terms of isotherms, streamlines, and Nusselt number. It is observed that the rate of heat transfer depends to a great extent on the Rayleigh number, Prandtl number, length of the corner heaters and the shape of the heat transfer surface. The consistent performance of the adopted numerical procedure is verified by comparison of the results obtained through the present meshless technique with those existing in the literature.

  8. Exploring attitudes towards aquaculture development in the UK: A consultative stakeholder approach

    OpenAIRE

    Memery, Juliet; Birch, Dawn

    2016-01-01

    This study explores attitudes towards aquaculture development as a way of providing a sustainable source of seafood through a consultative stakeholder approach. Given aquaculture is a less familiar concept within South West England, gaining insight of the views and perspectives of such a development in the region is required to facilitate stakeholder engagement. In-depth qualitative interviews investigate attitudes across five stakeholder sectors: government, fishing/marine, business/catering...

  9. 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....

  10. Fish production practices and use of aquaculture technologies ...

    African Journals Online (AJOL)

    The study investigated types of improved aquaculture technologies used by the ... fish farmers culture fish in earthen ponds, for commercial and home consumption ... fishes/m2 (98.3%), water quality management (99.1%) and fish ...

  11. Approaches for quantifying reactive and low-volatility biogenic organic compound emissions by vegetation enclosure techniques - part A.

    Science.gov (United States)

    Ortega, John; Helmig, Detlev

    2008-06-01

    The high reactivity and low vapor pressure of many biogenic volatile organic compounds (BVOC) make it difficult to measure whole-canopy fluxes of BVOC species using common analytical techniques. The most appropriate approach for estimating these BVOC fluxes is to determine emission rates from dynamic vegetation enclosure measurements. After scaling leaf- and branch-level emission rates to the canopy level, these fluxes can then be used in models to determine BVOC influences on atmospheric chemistry and aerosol processes. Previously published reports from enclosure measurements show considerable variation among procedures with limited guidelines or standard protocols to follow. This article reviews this literature and describes the variety of enclosure types, materials, and analysis techniques that have been used to determine BVOC emission rates. The current review article is followed by a companion paper which details a comprehensive enclosure technique that incorporates both recommendations from the literature as well as insight gained from theoretical calculations and practical experiences. These methods have yielded new BVOC emission data for highly reactive monoterpenes (MT) and sesquiterpenes (SQT) from a variety of vegetation species.

  12. Mixed convection from a discrete heat source in enclosures with two adjacent moving walls and filled with micropolar nanofluids

    Directory of Open Access Journals (Sweden)

    Sameh E. Ahmed

    2016-03-01

    Full Text Available This paper examines numerically the thermal and flow field characteristics of the laminar steady mixed convection flow in a square lid-driven enclosure filled with water-based micropolar nanofluids by using the finite volume method. While a uniform heat source is located on a part of the bottom of the enclosure, both the right and left sidewalls are considered adiabatic together with the remaining parts of the bottom wall. The upper wall is maintained at a relatively low temperature. Both the upper and left sidewalls move at a uniform lid-driven velocity and four different cases of the moving lid ordinations are considered. The fluid inside the enclosure is a water based micropolar nanofluid containing different types of solid spherical nanoparticles: Cu, Ag, Al2O3, and TiO2. Based on the numerical results, the effects of the dominant parameters such as Richardson number, nanofluid type, length and location of the heat source, solid volume fractions, moving lid orientations and dimensionless viscosity are examined. Comparisons with previously numerical works are performed and good agreements between the results are observed. It is found that the average Nusselt number along the heat source decreases as the heat source length increases while it increases when the solid volume fraction increases. Also, the results of the present study indicate that both the local and the average Nusselt numbers along the heat source have the highest value for the fourth case (C4. Moreover, it is observed that both the Richardson number and moving lid ordinations have a significant effect on the flow and thermal fields in the enclosure.

  13. Resistor capacitor, primitive variable solution of buoyant fluid flow within an enclosure with highly temperature dependent viscosity

    Energy Technology Data Exchange (ETDEWEB)

    Burns, S.P. [Texas Univ., Austin, TX (United States); Gianoulakis, S.E. [Sandia National Labs., Albuquerque, NM (United States)

    1995-07-01

    A numerical solution for buoyant natural convection within a square enclosure containing a fluid with highly temperature dependent viscosity is presented. Although the fluid properties employed do not represent any real fluid, the large variation in the fluid viscosity with temperature is characteristic of turbulent flow modeling with eddy-viscosity concepts. Results are obtained using a primitive variable formulation and the resistor method. The results presented include velocity, temperature and pressure distributions within the enclosure as well as shear stress and heat flux distributions along the enclosure walls. Three mesh refinements were employed and uncertainty values are suggested for the final mesh refinement. These solutions are part of a contributed benchmark solution set for the subject problem.

  14. Scaling-up Sustainable Aquaculture Development in Sri Lanka ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... of Sri Lanka is increasingly emphasizing aquaculture development as a means to foster ... Pilot interventions tested the effectiveness of mobile short text messaging to ... Building on this project, researchers will test three ways of scaling-up ...

  15. 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

  16. Fish farmers' perceptions of constraints affecting aquaculture ...

    African Journals Online (AJOL)

    The study focused on fish farmers' perceptions of constraints affecting aquaculture development in Akwa-Ibom State of Nigeria. Random sampling procedure was used to select 120 respondents from whom primary data was collected. Data analysis was with the aid of descriptive statistics. Results show that fish farming ...

  17. Evaluation of climatic vibration testing on plastic waterproof enclosure for electronic equipment using ANSYS[reg] workbench

    International Nuclear Information System (INIS)

    Aw, K.C.; Huang, W.D.J.; De Silva, M.W.R.P.

    2007-01-01

    Designing and testing of waterproof enclosure for electronic equipment involves significant amount of time and resources. This paper concentrates on electronic equipment used for maritime application. Typical waterproof test perform is based on the IEC 60529 standards and is insufficient to determine its reliability. Since, these enclosures were subjected to environmental stress such as heat and vibration and there is a need to understand how these affect the waterproof performance. Simulation using ANSYS workbench software was performed to comprehend the effect of various parameters of accelerated testing performed on these waterproof enclosures. Experiments were performed to examine the correlation with simulation results. The results confirmed that accelerated testing with random vibration at cold temperature causes greatest stress and causes degradation to adhesive bonds and hence affect the waterproof performance

  18. Analytical Modeling of Natural Convection in a Tall Rectangular Enclosure with Multiple Disconnected Partitions

    Directory of Open Access Journals (Sweden)

    Youngmin Bae

    2016-08-01

    Full Text Available In this study, laminar natural circulation and heat transfer in a tall rectangular enclosure with disconnected vertical partitions inside were investigated. Analytical expressions were developed to predict the circulation flow rate and the average Nusselt number in a partially partitioned enclosure with isothermal side walls at different temperatures and insulated top and bottom walls. The proposed formulas are then validated against numerical results for modified Rayleigh numbers of up to 106. The impacts of the governing parameters are also examined along with a discussion of the heat transfer regimes.

  19. How can plant genetic engineering contribute to cost-effective fish vaccine development for promoting sustainable aquaculture?

    Science.gov (United States)

    Clarke, Jihong Liu; Waheed, Mohammad Tahir; Lössl, Andreas G; Martinussen, Inger; Daniell, Henry

    2013-09-01

    Aquaculture, the fastest growing food-producing sector, now accounts for nearly 50 % of the world's food fish (FAO in The state of world fisheries and aquaculture. FAO, Rome, 2010). The global aquaculture production of food fish reached 62.7 million tonnes in 2011 and is continuously increasing with an estimated production of food fish of 66.5 million tonnes in 2012 (a 9.4 % increase in 1 year, FAO, www.fao.org/fishery/topic/16140 ). Aquaculture is not only important for sustainable protein-based food fish production but also for the aquaculture industry and economy worldwide. Disease prevention is the key issue to maintain a sustainable development of aquaculture. Widespread use of antibiotics in aquaculture has led to the development of antibiotic-resistant bacteria and the accumulation of antibiotics in the environment, resulting in water and soil pollution. Thus, vaccination is the most effective and environmentally-friendly approach to combat diseases in aquaculture to manage fish health. Furthermore, when compared to >760 vaccines against human diseases, there are only about 30 fish vaccines commercially available, suggesting the urgent need for development and cost-effective production of fish vaccines for managing fish health, especially in the fast growing fish farming in Asia where profit is minimal and therefore given high priority. Plant genetic engineering has made significant contributions to production of biotech crops for food, feed, valuable recombinant proteins etc. in the past three decades. The use of plants for vaccine production offers several advantages such as low cost, safety and easy scaling up. To date a large number of plant-derived vaccines, antibodies and therapeutic proteins have been produced for human health, of which a few have been made commercially available. However, the development of animal vaccines in plants, especially fish vaccines by genetic engineering, has not yet been addressed. Therefore, there is a need to exploit

  20. Use of chemicals in aquaculture - issues of concern

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.

    Majority of aquaculture practices are still based on extensive and semi-intensive farming systems though a trend to intensify operations to enhance yields and improve the efficiency of the production process has emerged in recent years. Apart from...

  1. Process and device for leak rate measurement of an enclosure

    International Nuclear Information System (INIS)

    Giroux, J.

    1989-01-01

    The volume of a cavity, such as a cylinder and a piston, connected to the enclosure (glovebox or reactor containment shell) is varied to find back the previous pressure difference with the outside (positive or negative). Thermometers and a barometer are provided for eventual corrections [fr

  2. Major viral diseases affecting fish aquaculture in Spain.

    Science.gov (United States)

    Pérez, S I; Rodríguez, S

    1997-06-01

    The number of viruses isolated from fish has grown in the last few years as a reflection of the increasing interest in fish diseases, particularly those occurring in aquaculture facilities. Of all the described viruses, only a few are considered to be of serious concern and economic importance; they are described in this review, drawing special attention to the four families of viruses (Birnaviridae, Rhabdoviridae, Iridoviridae and Reoviridae) that have been reported in Spanish aquaculture. Infectious pancreatic necrosis virus, a member of the first family, is the most spread virus with a prevalence of 39%. Viral diseases are untreatable and because effective and safe vaccines for fish are not yet commercially available, a great care needs to be exercised when moving fish or eggs from one site or country to another. Some fish health control regulations have been legislated in Europe and USA.

  3. Bivalve aquaculture transfers in Atlantic Europe. Part A: Transfer activities and legal framework

    DEFF Research Database (Denmark)

    Muehlbauer, F.; Fraser, D.; Brenner, M.

    2014-01-01

    environment and address economic considerations remains unanswered. This study provides the first overview of bivalve transfer activities for aquaculture purposes along the European Atlantic coast. Existing international and EU legislation is described, and potential weaknesses in the existing legislative......Intentional transfers of numerous bivalve species have had a long tradition and are commonly conducted along the European Atlantic coast. However numerous studies have concluded that intentional transfer of species for aquaculture purposes is one of the most principal vectors for the introduction...... frameworks are discussed. Recommendations for the development of integrated risk assessment methods are given. These may help to minimize the intrinsic threats of transfer activities in marine environments. The resulting impacts and effects of transfer activities of bivalves for aquaculture purpose...

  4. Business opportunities for aquaculture in Kenya; With special reference to food security : Key findings & Recommendations

    NARCIS (Netherlands)

    Rothuis, A.J.; Duijn, van A.P.; Rijsingen, J.C.M.; Pijl, van der W.; Rurangwa, E.

    2011-01-01

    This study aims to assess the potential role of aquaculture in improving food security in Kenya. It addresses current bottlenecks that prevent aquaculture from achieving its food security objectives and identifies possible interventions. This study furthermore explores business opportunities for

  5. A techno-economic analysis of aquaculture business in Ogun State, Nigeria

    Science.gov (United States)

    Kareem, R. O.; Williams, S. B.

    2009-05-01

    Fish supplies 25% of the total protein source in developing countries. A techno-economic analysis was performed for developing a good business proposal for aquaculture loans to enhance aquaculture development in Nigeria. A case study of catfish Clarias gariepinus framing was conducted in Abeokuta North Local Government of Ogun State, Nigeria. The results show that the fixed cost is N18 338 per year, and the variable cost is N459 700 per year, accounting for the largest amount of the total; therefore, a profit of N43 289 per month can be made. Sensitivity analysis was performed to assess any risk(s) that associated with unfavorable changes in government policy with particular reference to monetary policy. Positive net present value shows that the investment in fish farm is economically feasible and the net investment ratio is 3.52. Also, the benefit-cost ratio is 2.17. The internal rate of return (IRR) is 21% showing that the enterprise is able to offset the interest being charged on the loan. It is therefore worthwhile to invest into fish farm business in the study area. The study suggests that to better sustain the local aquaculture business, the government should create a good conducive environment to foster development of the fish farming. Government intervention is urgently needed to solve problems such as in traditional land tenure, grant credit facilities and subsidies, to enhance the aquacultural development in the country.

  6. Shielded enclosure for handling radioactive material; Sorbonnes blindees pour manipulations radioactives

    Energy Technology Data Exchange (ETDEWEB)

    Laurent, H; Courouble, J M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-07-01

    Two enclosures linked by an air-lock are described: they are designed for the safe handling of 5 curies 0.3 to 0.5 MeV {gamma} emitters, and each is composed of a semi-tight case, ventilated, clad in 80 mm steel plate, and suited for a wide variety of physics and chemistry operations. The equipment required for any given operation can be installed in the shortest possible time, access to the enclosure being via a removable front. Visual control is assured through a lead-glass screen. Each enclosure is fitted with a master-slave manipulator, Argon model 7, and plugs and air-locks are provided for the introduction of liquids and solids. (author) [French] On decrit deux enceintes reliees par un sas pour manipulation sur 5 curies d'emetteurs {gamma} de 0,3 a 0,5 MeV. Chacune des enceintes est constituee d'une boite semi-etanche, ventilee, entouree de toles d'acier de 80 mm. L'ensemble est concu pour y effectuer les operations physiques ou chimiques les plus variees. L'equipement necessaire a une manipulation donnee peut y etre installe dans le minimum de temps, l'acces se faisant par la face avant qui peut se deplacer. Une dalle de verre au plomb assure la vision. Chacune des sorbonnes est equipee d'une paire de telemanipulateurs Argonne modele 7. Des sas et des bouchons assurent le passage des solides et des fluides. (auteur)

  7. Effectiveness of pads and enclosures as safety interventions on consumer trampolines

    Science.gov (United States)

    Eager, David; Scarrott, Carl; Sushinsky, George

    2010-01-01

    Background Trampolines continue to be a major source of childhood injury. Objective To examine available data on trampoline injuries in order to determine the effectiveness of padding and enclosures. Design Trampoline injuries from the NEISS database from 2002 to 2007 were reclassified into five cause-categories, to examine evidence for injury trends. Setting The ASTM trampoline standard recommendations for safety padding were upgraded in 1999 and enclosures were introduced in 1997. This is the first study to examine the impact of these changes. Patients The sampling frame comprises patients with NEISS product code ‘consumer trampolines’ (1233). A systematic sample of 360 patients each year is taken. Interventions The prominent interventions recommended by the ASTM are netting enclosures to prevent falling off and safety padding to cover frames and springs. Main outcome measures Proportion of injuries within each cause-category and trend estimates. Results There was no evidence for a decline within the injury cause-categories that should be prevented by these interventions from 2002 to 2007. Conclusions If these interventions were effective the associated injury causes would be in decline. Instead they remain close to half of all trampoline injuries with no significant change over the period of the study. Follow-up studies are proposed to determine the reasons. Given the number of injuries involved it is recommended that steps be taken to ensure these safety interventions or their equivalents are in place, work properly and remain effective for the life of consumer trampolines. PMID:20570986

  8. Enhancing monochromatic multipole emission by a subwavelength enclosure of degenerate Mie resonances

    KAUST Repository

    Zhao, Jiajun; Zhang, Likun; Wu, Ying

    2017-01-01

    of the enclosure, and meanwhile the radiation directivity pattern is well preserved. The degeneracy is theoretically analyzed. A realization of the material is suggested by using a space-coiling structure.

  9. Components for containment enclosures. Part 4: Ventilation and gas-cleaning systems such as filters, traps, safety and regulation valves, control and protection devices

    International Nuclear Information System (INIS)

    2001-01-01

    ISO 11933 consists of the following parts, under the general title Components for containment enclosures: Part 1: Glove/bag ports, bungs for glove/bag ports, enclosure rings and interchangeable units; Part 2: Gloves, welded bags, gaiters for remote-handling tongs and for manipulators; Part 3: Transfer systems such as plain doors, airlock chambers, double door transfer systems, leaktight connections for waste drums; Part 4: Ventilation and gas-cleaning systems such as filters, traps, safety and regulation valves, control and protection devices; Part 5: Penetrations for electrical and fluid circuits. This part of ISO 11933 specifies the design criteria and the characteristics of various components used for ventilation and gas-cleaning in containment enclosures. These components are either directly fixed to the containment enclosure wall, or used in the environment of a shielded or unshielded containment enclosure or line of such enclosures. They can be used alone or in conjunction with other mechanical components, including those specified in ISO 11933-1 and ISO 11933-3. This part of ISO 11933 is applicable to: filtering devices, including high-efficiency particulate air (HEPA) filters and iodine traps; safety valves and pressure regulators; systems ensuring the mechanical protection of containment enclosures; control and pressure-measurement devices

  10. AQUACULTURE AS A MEXICAN STRATEGY FOR ECONOMIC DEVELOPMENT OF COASTAL AND RURAL AREAS

    Directory of Open Access Journals (Sweden)

    Antonio Mártir Mendoza

    2006-09-01

    Full Text Available SUMMARYAquaculture is one of the worldwide economic activities which has grown in the last 30 years at an annual rate of 9-10.0 %. Poultry, pork, lamb and beef meat production have increased only at an annual rate of 3.0 % in the same period, and in the last five years has decreased due to aviar fever and other viral difficulties. While aquaculture growth takes place in far away countries as China near by countries as Costa Rica, Honduras, Brazil and Chile keeps the same tendency. As far as Mexico´s aquaculture is concerned, it has grown steadily, missing, even its way out. On the one hand fish catches do not grow since the middle of the 80´s when fish production reached 1.5 million tones. On the other hand aquaculture in fresh waters and in sea waters are almost staging due to the loss of authority and governmental management capacity to make decisions. The recently elected federal government which will take office next December 1st, has on its hands the opportunity to favor aquaculture production and doing so, to develop Mexican coastal and rural areas.

  11. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    NARCIS (Netherlands)

    Cranford, P.J.; Kamermans, P.; Krause, G.H.M.; Mazurie, J.

    2012-01-01

    An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and

  12. Design & Test of Radio Communication and Control System for Aquaculture

    Directory of Open Access Journals (Sweden)

    Fengrong Jia

    2013-05-01

    Full Text Available Aiming at low automation degree and backward aquatic product management of current aquaculture in China, this paper designed a set of radio communication and control system which consists of 3 parts of information collection module, control module and radio communication module. This system both realizes wireless monitoring of quality parameters of water for aquaculture and realizes wireless control of water level and dissolved oxygen value through radio communication. Test results show that data transfer is more accurate and reliable after adding customized protocol and answer signals in radio communication. The highest error and missing rate within 1000 m is 0.36, the lowest error and missing rate is 0.05 and the longest response time is 49 ms. The dissolved oxygen value detection system designed in this paper is close to the testing value of existing dissolved oxygen value transmitter DO6309. With wireless data transfer mode, it has higher practicality. The wireless control of dissolved oxygen value and water level can be controlled within the appropriate range with stable and precise control. The study results can provide intelligent aquaculture model with simple operation and precise control for enormous aquatic breeders

  13. Aquaculture-oriented genetic researches in abalone: Current status ...

    African Journals Online (AJOL)

    Hybridization, triploidization and genetic mapping were also briefly reviewed as aquaculture-oriented genetic techniques to improve growth and other commercially important traits. Cryopreservation and other biotechnologies potentially applicable on genetic improvement were also briefly mentioned as supporting tools for ...

  14. Development of enclosure technique of tag gas for in-pile creep test

    International Nuclear Information System (INIS)

    Izaki, Toru; Ichikawa, Shoichi; Soroi, Masatoshi; Ito, Chikara

    2004-01-01

    Outline of the enclosure technique of tag gas for in-pile creep test is stated. In order to carry out in-pile creep test, the sample can enclose tag gas before the test and then the sample is inserted into MARICO-2 (Material Testing Rig with Temperature Control) in FBR 'JOYO' MK-III for the irradiation test. Outline of in-pile creep test using tag gas, enclosure system of tag gas, detection of a part of broken sample and identification of sample are explained. 126-, 128-, 129-, 131-, 132-, and 134-Xe are used as tag gases. The samples are identified by RIMS (Laser Resonance Ionization Mass Spectroscopy) in ppt order. ODS ferritic steel will be tested by the method in the next step. (S.Y.)

  15. National Strategic Environmental Assessment for aquaculture development in South Africa: GIS analysis for identifying optimal areas for marine and freshwater aquaculture development

    CSIR Research Space (South Africa)

    Snyman-van der Walt, Luanita

    2017-06-01

    Full Text Available The Department of Environmental Affairs and the Department of Agriculture, Forestry and Fisheries commissioned the Council for Scientific and Industrial Research to conduct a Strategic Environmental Assessment (SEA) for Aquaculture Development...

  16. Tridentine enclosure gaps. Controversies and Limitations of Policies for Nuns…Still with Felipe IV

    Directory of Open Access Journals (Sweden)

    Ángela Atienza López

    2014-12-01

    Full Text Available The Council of Trent ordered that the strict enclosure for nuns should be carried out. The aim of this paper is to contribute to the analysis of those provisions, pointing out that such monastic discipline had a highly questionable success. The process was full of problems. Even one century after Trent, King Felipe IV still cried out to the situation and deployed a political offensive to reach its imposition. The study of these sources allows us to show the Trent enclosure gaps: how the lack of consent was spread even among the elites of secular and ecclesiastical power, and it hampered its implementation; also how the reality of monastic vows and convent life imposed limits hindering its success; how nuns refused and got support from different sectors; and, on the end, how daily practice of enclosure ran through other channels, where stringency rules could be reconsidered in time and place and could meet their arrangements, more or less lenient, and could be negotiated and renegotiated in everyday life, so that strains could be overcome.

  17. Measuring System for Growth Control of the Spirulina Aquaculture

    Science.gov (United States)

    Ponce S., Claudio; Ponce L., Ernesto; Bernardo S., Barraza

    2008-11-01

    It describes the workings of a data-logging instrument that measures growth levels of the Spirulina aquaculture. The Spirulina is a very delicate algae and its culture may be suddenly lost due to overgrowth. This kind of instrument is not at present available in the market. The transduction is a submergible laser device whose measuring margin of error is near to 0.28%. The advantage of this new instrument is the improvement in the measurement and the low cost. The future application of this work is related to the industrial production of food and fuel from micro algae culture, for the growing world population.

  18. The effects of varied densities on the growth and emigration of adult cutthroat trout and brook trout in fenced stream enclosures

    Science.gov (United States)

    Buys, D.J.; Hilderbrand, R.H.; Kershner, J.L.

    2009-01-01

    We evaluated the effects of various density treatments on adult fish growth and emigration rates between Bonneville cutthroat trout Oncorhynchus clarki utah and brook trout Salvelinus fontinalis in stream enclosures in Beaver Creek, Idaho, We used 3 density treatments (low, ambient, and high fish densities) to evaluate density-related effects and to ensure a response. Intraspecific ambient-density tests using cutthroat trout only were also performed. Results indicated an absence of cage effects in the stream enclosures and no differences in fish growth between ambient-density stream-enclosure fish and free-range fish. Brook trout outgrew and moved less than cutthroat trout in the stream enclosures, especially as density increased, In all 3 density treatments, brook trout gained more weight than cutthroat trout, with brook trout gaining weight in each density treatment and cutthroat trout losing weight at the highest density. At high densities, cutthroat trout attempted to emigrate more frequently than brook trout in sympatry and allopatry. We observed a negative correlation between growth and emigration for interspecific cutthroat trout, indicating a possible competitive response due to the presence of brook trout. We observed similar responses for weight and emigration in trials of allopatric cutthroat trout, indicating strong intraspecific effects as density increased. While cutthroat trout showed a response to experimental manipulation with brook trout at different densities, there has been long-term coexistence between these species in Beaver Creek, This system presents a unique opportunity to study the mechanisms that lead cutthroat trout to coexist with rather than be replaced by nonnative brook trout.

  19. Management of marine cage aquaculture. Environmental carrying capacity method based on dry feed conversion rate.

    Science.gov (United States)

    Cai, Huiwen; Sun, Yinglan

    2007-11-01

    Marine cage aquaculture produces a large amount of waste that is released directly into the environment. To effectively manage the mariculture environment, it is important to determine the carrying capacity of an aquaculture area. In many Asian countries trash fish is dominantly used in marine cage aquaculture, which contains more water than pellet feed. The traditional nutrient loading analysis is for pellet feed not for trash fish feed. So, a more critical analysis is necessary in trash fish feed culturing areas. Corresponding to FCR (feed conversion rate), dry feed conversion rate (DFCR) was used to analyze the nutrient loadings from marine cage aquaculture where trash fish is used. Based on the hydrodynamic model and the mass transport model in Xiangshan Harbor, the relationship between the water quality and the waste discharged from cage aquaculture has been determined. The environmental carrying capacity of the aquaculture sea area was calculated by applying the models noted above. Nitrogen and phosphorus are the water quality parameters considered in this study. The simulated results show that the maximum nitrogen and phosphorus concentrations were 0.216 mg/L and 0.039 mg/L, respectively. In most of the sea area, the nutrient concentrations were higher than the water quality standard. The calculated environmental carrying capacity of nitrogen and phosphorus in Xiangshan Harbor were 1,107.37 t/yr and 134.35 t/yr, respectively. The waste generated from cage culturing in 2000 has already exceeded the environmental carrying capacity. Unconsumed feed has been identified as the most important origin of all pollutants in cage culturing systems. It suggests the importance of increasing the feed utilization and improving the feed composition on the basis of nutrient requirement. For the sustainable development of the aquaculture industry, it is an effective management measure to keep the stocking density and pollution loadings below the environmental carrying

  20. The role of shellfish aquaculture in reduction of eutrophication in an urban estuary

    DEFF Research Database (Denmark)

    Bricker, Suzanne B.; Ferreira, Joao Gomes; Zhu, Changbo

    2018-01-01

    from the system-scale modeling, suggesting that this upscaling method could be useful in waterbodies without circulation models. The minimum value of the ecosystem service of nitrogen removed by oyster production was estimated by means of an avoided costs method, which uses the cost of alternative......, as an example of how aquaculture might complement land-based measures in urban estuaries. Eutrophication status, nutrient removal, and ecosystem service value were estimated through eutrophication assessment, application of hydrologic, circulation, and local- and ecosystem-scale models, and economic valuation....... System-scale modeling estimated that current oyster aquaculture, via sequestration into tissue and shell only, removes an equivalent of 1.31%, and expanded production could remove 2.68%, of total annual land-based nitrogen inputs by aquaculture alone. Up-scaled local-scale results were similar to results...

  1. Distribution of quantum states in enclosures of finite size I

    International Nuclear Information System (INIS)

    Souto, J.H.; Chaba, A.N.

    1989-01-01

    The expression for the density of states of a particle in a three-dimensional rectangular box of finite size can be obtained directly by Poissons's Summation formula. The expression for the case of an enclosure in the form of an infinite rectangular slab is derived. (A.C.A.S.) [pt

  2. Sea cucumbers reduce chromophoric dissolved organic matter in aquaculture tanks.

    Science.gov (United States)

    Sadeghi-Nassaj, Seyed Mohammad; Catalá, Teresa S; Álvarez, Pedro A; Reche, Isabel

    2018-01-01

    waters (average: 0.32 m -1 and 22 µm -1 , respectively). This reduction in the absorption of the dissolved organic matter appears to be mediated by the POM consumption by holothurians. The experiments confirmed the results observed in the time-series. The a 325 and S 275-295 values were significantly lower in the treatment with holothurians than in the treatment without holothurians indicating a reduction in the concentration of chromophoric organic compounds, particularly of low molecular weight. Consequently, sea cucumbers appear to improve water transparency in aquaculture tanks. The underlying mechanism of this improvement might be related to the POM consumption by holothurians, which reduces the concentration of CDOM derived from POM disaggregation or to the direct assimilation of dissolved compounds of low molecular weight as chromophoric amino acids.

  3. Biotechnology and species development in aquaculture | Ayoola ...

    African Journals Online (AJOL)

    The use of biotechnology in various aspects of human endeavour have obviously created a great impact but not without some risks. Not withstanding, there is still the need for its adoption as more of the already adopted biotechnologies are being improved upon with lesser demerits. Aquaculture is not also left out in the ...

  4. 1 Ammonia Concentrations in Different Aquaculture 2

    African Journals Online (AJOL)

    Administrator

    Introduction. Most studies have shown that the best feed for optimal fish production in aquaculture is one rich in high amount of protein. The amount of protein in the ..... Aquatic Science, Florida Coop, Ext. Serv. FA-16, 4 pp. Hargreaves J. A. and Tucker C. S. (2004). Managing. Ammonia in Fish Ponds. SRAC Publication Fact.

  5. Update to the Atlantic salmon breeding program at the National Cold Water Marine Aquaculture Center

    Science.gov (United States)

    The USDA-ARS National Cold Water Marine Aquaculture Center (NCWMAC) in Franklin, ME has been supporting the U.S. coldwater marine aquaculture industry for the past thirteen years by developing a genetically improved North American Atlantic salmon. The St. John's River stock was chosen as the focal ...

  6. 40 CFR 122.25 - Aquaculture projects (applicable to State NPDES programs, see § 123.25).

    Science.gov (United States)

    2010-07-01

    ... DISCHARGE ELIMINATION SYSTEM Permit Application and Special NPDES Program Requirements § 122.25 Aquaculture... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Aquaculture projects (applicable to State NPDES programs, see § 123.25). 122.25 Section 122.25 Protection of Environment ENVIRONMENTAL...

  7. Magnetometric prospection of various types of large ditched enclosures in Bohemia

    Czech Academy of Sciences Publication Activity Database

    Křivánek, Roman

    2006-01-01

    Roč. 13, č. 1 (2006), s. 25-43 ISSN 1075-2196 R&D Projects: GA ČR GV404/97/K024 Institutional research plan: CEZ:AV0Z80020508 Keywords : prospection * ditch enclosure * magnetometer Subject RIV: AC - Archeology, Anthropology, Ethnology

  8. Water quality, seasonality, and trajectory of an aquaculture-wastewater plume in the Red Sea

    KAUST Repository

    Hozumi, Aya; Hong, Pei-Ying; Kaartvedt, S; Rø stad, Anders; Jones, Burton

    2017-01-01

    As aquaculture activity increases globally, understanding water mass characteristics of the aquaculture-wastewater plume, its nutrients, and its organic matter load and spatial distribution in the coastal recipient, is critical to develop a more sustainable aquaculture operation and to improve coastal management. We examined wastewater (estimated 42-48 m3 s-1) discharged from the largest aquaculture facility in the Red Sea and surveyed the area around the aquaculture outfall to characterize the biogeochemical properties of the wastewater plume and its spatial distribution. In addition, we assessed its associated microbial community structure. The plume was characterized by elevated levels of salinity, density, and turbidity, and traveled along paths determined by the bathymetry to form a dense, 1-3 m thick layer above the seafloor. The effluent was observed at least 3.8 km from the outfall throughout the year, but up to 8 km in early autumn. The total nitrogen concentration in the plume was more than 4 times higher than in surface waters 1.4 km from the outfall. High-throughput sequencing data revealed that bacterial and cyanobacterial communities significantly differed, and flow cytometry results showed that total cell counts were significantly higher at the outfall. Arcobacter, a genus associated with opportunistic pathogenic species (e.g. A. butzleri), was more abundant, while Prochlorococcus sp. was significantly less abundant at the outfall. This dense, bottom-flowing plume may have a detrimental impact on benthic and demersal communities.

  9. Water quality, seasonality, and trajectory of an aquaculture-wastewater plume in the Red Sea

    KAUST Repository

    Hozumi, Aya

    2017-12-28

    As aquaculture activity increases globally, understanding water mass characteristics of the aquaculture-wastewater plume, its nutrients, and its organic matter load and spatial distribution in the coastal recipient, is critical to develop a more sustainable aquaculture operation and to improve coastal management. We examined wastewater (estimated 42-48 m3 s-1) discharged from the largest aquaculture facility in the Red Sea and surveyed the area around the aquaculture outfall to characterize the biogeochemical properties of the wastewater plume and its spatial distribution. In addition, we assessed its associated microbial community structure. The plume was characterized by elevated levels of salinity, density, and turbidity, and traveled along paths determined by the bathymetry to form a dense, 1-3 m thick layer above the seafloor. The effluent was observed at least 3.8 km from the outfall throughout the year, but up to 8 km in early autumn. The total nitrogen concentration in the plume was more than 4 times higher than in surface waters 1.4 km from the outfall. High-throughput sequencing data revealed that bacterial and cyanobacterial communities significantly differed, and flow cytometry results showed that total cell counts were significantly higher at the outfall. Arcobacter, a genus associated with opportunistic pathogenic species (e.g. A. butzleri), was more abundant, while Prochlorococcus sp. was significantly less abundant at the outfall. This dense, bottom-flowing plume may have a detrimental impact on benthic and demersal communities.

  10. Scaling-up Sustainable Aquaculture Development in Sri Lanka ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The project will also test the efficacy of different governance models for sustainable aquaculture management, to understand which institutional partnerships work best for knowledge mobilization. Third, the project will find ways to overcome factors currently limiting sustainable production, namely the supply of fingerlings for ...

  11. Safety of stationary grinding machines - impact resistance of work zone enclosures.

    Science.gov (United States)

    Mewes, Detlef; Adler, Christian

    2017-09-01

    Guards on machine tools are intended to protect persons from being injured by parts ejected with high kinetic energy from the work zone of the machine. Stationary grinding machines are a typical example. Generally such machines are provided with abrasive product guards closely enveloping the grinding wheel. However, many machining tasks do not allow the use of abrasive product guards. In such cases, the work zone enclosure has to be dimensioned so that, in case of failure, grinding wheel fragments remain inside the machine's working zone. To obtain data for the dimensioning of work zone enclosures on stationary grinding machines, which must be operated without an abrasive product guard, burst tests were conducted with vitrified grinding wheels. The studies show that, contrary to widely held opinion, narrower grinding wheels can be more critical concerning the impact resistance than wider wheels although their fragment energy is smaller.

  12. Japanese aquaculture: use of thermal water from power plant

    International Nuclear Information System (INIS)

    Kuroda, Takeya

    1983-01-01

    There is some merit of thermal water from power plants in the effect to marine life. Since 1963, the research and development on the aquaculture using this warm water have been carried out at some twenty power plants, seven nuclear and thirteen thermal, some of which are now in the commercial stage. These fish farming projects are operated variously from seed to adult fish production. They can also be classified as land and sea facilities, conforming to the characteristics of the respective sea areas. The current situation in this field and the future prospect are described: thermal aquaculture including seed production and adult fish farming; the projects in nuclear and thermal power plants, respectively; future problems in the facilities, breeding environment and marine life for cultivation. (Mori, K.)

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

    Directory of Open Access Journals (Sweden)

    H.M. Joesting

    2016-05-01

    Full Text Available 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 to investigate the use of marine aquaculture solid waste as a nutrient source for the nursery production of two salt tolerant plants commonly used in coastal salt marsh restoration, Spartina alterniflora (smooth cordgrass and Juncus roemerianus (black needlerush. Specifically, measurements of plant biomass and tissue nitrogen and phosphorus allocation were compared between plants fertilized with dried shrimp biofloc solids and unfertilized controls, as well as between plants fertilized with dried fish solids and unfertilized controls. In both experiments, S. alterniflora plants fertilized with marine aquaculture solids showed few significant differences from unfertilized controls, whereas fertilized J. roemerianus plants had significantly greater biomass and absorbed and incorporated more nutrients in plant tissue compared to unfertilized controls. These results suggest that J. roemerianus may be a suitable plant species for the remediation of marine aquaculture solid waste. Keywords: Marine aquaculture, Salt marsh plants, Solid waste, Phytoremediation

  14. Decay of reverberant sound in a spherical enclosure

    International Nuclear Information System (INIS)

    Carroll, M.M.; Chien, C.F.

    1977-01-01

    The assumption of diffuse reflection (Lambert's Law) leads to integral equations for the wall intensity in a reverberant sound field in the steady state and during decay. The latter equation, in the special case of a spherical enclosure with uniformly absorbent walls and uniform wall intensity, allows exponential decay with a decay time which agrees closely with the Norris--Eyring prediction. The sound-intensity and sound-energy density in the medium, during decay, are also calculated

  15. Antibacterial activity of oxytetracycline photoproducts in marine aquaculture's water.

    Science.gov (United States)

    Leal, J F; Henriques, I S; Correia, A; Santos, E B H; Esteves, V I

    2017-01-01

    Oxytetracycline (OTC) is one of the most used antibiotics in aquaculture. The main concern related to its use is the bacterial resistance, when ineffective treatments are applied for its removal or inactivation. OTC photo-degradation has been suggested as an efficient complementary process to conventional methods used in intensive fish production (e.g.: ozonation). Despite this, and knowing that the complete mineralization of OTC is difficult, few studies have examined the antibacterial activity of OTC photoproducts. Thus, the main aim of this work is to assess whether the OTC photoproducts retain the antibacterial activity of its parent compound (OTC) after its irradiation, using simulated sunlight. For that, three Gram-negative bacteria (Escherichia coli, Vibrio sp. and Aeromonas sp.) and different synthetic and natural aqueous matrices (phosphate buffered solutions at different salinities, 0 and 21‰, and three different samples from marine aquaculture industries) were tested. The microbiological assays were made using the well-diffusion method before and after OTC has been exposed to sunlight. The results revealed a clear effect of simulated sunlight, resulting on the decrease or elimination of the antibacterial activity for all strains and in all aqueous matrices due to OTC photo-degradation. For E. coli, it was also observed that the antibacterial activity of OTC is lower in the presence of sea-salts, as demonstrated by comparison of halos in aqueous matrices containing or not sea-salts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Current Status of Federal Involvement in U.S. Aquaculture

    National Research Council Canada - National Science Library

    1995-01-01

    ...; little reached commercial markets. Although trout had been produced for food since the turn of the century, only with the advent of the catfish culture industry did commercial aquaculture gain visibility as a market force...

  17. Managing socio-institutional enclosure: A grounded theory of caregivers' attentiveness in hospital care.

    Science.gov (United States)

    Klaver, Klaartje; Baart, Andries

    2016-06-01

    Caregivers' attentiveness is vital for healthcare quality, yet existing research lacks a specific definition and neglects its different forms and aspects. This paper presents a qualitative, grounded theory of attentiveness in hospital oncology care. Our data show nine types of attentiveness. We answer the question why a caregiver practices one type of attentiveness in a certain situation, and not another type. First, it appears to be of crucial importance whether attentiveness is essential for giving care in the opinion of the caregiver. Second, the focus of attention is essential. Care given by doctors and nurses is always ambivalent; on the one hand, it concerns the body, and on the other hand, it involves the person whom that body belongs to. What is the caregiver (mainly) focused on? The significance of socio-institutional enclosure emerged as a key theme within the findings. Socio-institutional enclosure concerns the space a caregiver may or may not experience to break free from the preponderant institutional orientation towards the physical body of the patient. At the intersection of the influence of socio-institutional enclosure and the substance of the caregivers' concepts of care, three cultures are found that comprise the different types of attentiveness. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds.

    Science.gov (United States)

    Anikuttan, K K; Adhikari, S; Kavitha, M; Jayasankar, P

    2016-07-01

    The contribution of aquaculture and allied activities to the emission of green house gases and consequently to global warming is an emerging concern among environmentalists in the recent past. However, there exists ample scope for aquaculture activities to sequester carbon and thus compensate for the carbon emissions linked to aquaculture. This article attempts to elucidate the carbon sequestration capacity of sediments, algae, and zooplankton from fresh water aquaculture ponds. The percent organic carbon in the pond sediments ranged from 0.39 to 1.31 with an average value of 0.912 ± 0.321 whereas the carbon sequestration capacity ranged from 0.442 to 1.882 MgC/ha (1 Mg = 10(6) g) with an average value of 1.018 ± 0.447 MgC/ha. In the case of zooplankton and algae from pond, the percent organic carbon was 7.688 ± 0.196 and 2.354 ± 0.047, respectively, whereas the total estimated carbon burial rate was 0.009 ± 0.005 and 0.150 ± 0.003 MgC/ha, respectively. These findings are discussed with the previous reports available at present and are found to be in comparable ranges.

  19. 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.

  20. Aquacultured Rainbow Trout (Oncorhynchus mykiss) Possess a Large Core Intestinal Microbiota That Is Resistant to Variation in Diet and Rearing Density

    Science.gov (United States)

    Wong, Sandi; Waldrop, Thomas; Summerfelt, Steven; Davidson, John; Barrows, Frederic; Kenney, P. Brett; Welch, Timothy; Wiens, Gregory D.; Snekvik, Kevin

    2013-01-01

    As global aquaculture fish production continues to expand, an improved understanding of how environmental factors interact in fish health and production is needed. Significant advances have been made toward economical alternatives to costly fishmeal-based diets, such as grain-based formulations, and toward defining the effect of rearing density on fish health and production. Little research, however, has examined the effects of fishmeal- and grain-based diets in combination with alterations in rearing density. Moreover, it is unknown whether interactions between rearing density and diet impact the composition of the fish intestinal microbiota, which might in turn impact fish health and production. We fed aquacultured adult rainbow trout (Oncorhynchus mykiss) fishmeal- or grain-based diets, reared them under high- or low-density conditions for 10 months in a single aquaculture facility, and evaluated individual fish growth, production, fin indices, and intestinal microbiota composition using 16S rRNA gene sequencing. We found that the intestinal microbiotas were dominated by a shared core microbiota consisting of 52 bacterial lineages observed across all individuals, diets, and rearing densities. Variations in diet and rearing density resulted in only minor changes in intestinal microbiota composition despite significant effects of these variables on fish growth, performance, fillet quality, and welfare. Significant interactions between diet and rearing density were observed only in evaluations of fin indices and the relative abundance of the bacterial genus Staphylococcus. These results demonstrate that aquacultured rainbow trout can achieve remarkable consistency in intestinal microbiota composition and suggest the possibility of developing novel aquaculture strategies without overtly altering intestinal microbiota composition. PMID:23770898

  1. Economic valuation of Mangroves for comparison with commercial aquaculture in south Sulawesi, Indonesia

    DEFF Research Database (Denmark)

    Malik, Abdul; Fensholt, Rasmus; Mertz, Ole

    2015-01-01

    Mangroves are recognized as a provider of a variety of products and essential ecosystem services that contribute significantly to the livelihood of local communities. However, over the past decades, mangroves in many tropical areas including the Takalar district, South Sulawesi have degraded...... and decreased mainly due to conversion to aquaculture. Currently, little is known about the economic benefits of commercialization of aquaculture as compared to those derived from mangroves in the form of products and services. Here, we estimate the Total Economic Value (TEV) of mangrove benefits in order...... to compare it with the benefit value of commercial aquaculture. Market prices, replacement costs, benefit transfer value and Cost-Benefit Analyses (CBA) have been used for value determination and comparison. The results show that the per year TEV of mangroves in the study area (Takalar district, South...

  2. Natural convection flow and heat transfer between a fluid layer and a porous layer inside a rectangular enclosure

    International Nuclear Information System (INIS)

    Beckermann, C.; Ramadhyani, S.; Viskanta, R.

    1986-01-01

    A numerical and experimental study is performed to analyze the steady-state natural convection fluid flow and heat transfer in a vertical rectangular enclosure that is partially filled with a vertical layer of a fluid-saturated porous medium. The flow in the porous layer is modeled utilizing the Brinkman-Forchheimer-extended Darcy equations. The numerical model is verified by conducting a number of experiments with spherical glass beads as the porous medium and water and glycerin as the fluids in rectangular test-cells. The agreement between the flow visualization results and temperature measurements and the numerical model is, in general, good. It is found that the amount of fluid penetrating from the fluid region into the porous layer depends strongly on the Darcy (Da) and Rayleigh (Ra) numbers. For a relatively low product of Ra x Da, the flow takes place primarily in the fluid layer, and heat transfer in the porous layer is by conduction only. On the other hand, fluid penetrating into a relatively highly permeable porous layer has a significant impact on the natural convection flow patterns in the entire enclosure

  3. Sustainable aquaculture in ponds: Principles, practices and limits

    NARCIS (Netherlands)

    Bosma, R.H.; Verdegem, M.C.J.

    2011-01-01

    The global aquaculture production of crustaceans, shellfish and fish has to increase to satisfy the growing demand and also to compensate for the reduced capture from overexploited fisheries. Extending the area of brackish and fresh water ponds is constrained by the limited availability of land and

  4. adoption of improved aquaculture practices by shrimp farmers

    African Journals Online (AJOL)

    Dr.Adesope

    use of check trays and adjustment of feed accordingly (95.0%), formation of ... Key words: adoption, improved aquaculture, shrimp farmers ... Brackish water shrimp farming is getting more attention because of high profitability ..... water and pond water whereas 52.5% of farmers did not observe the actual acclimatisation.

  5. Selection of sustainable seaweed and grouper aquaculture development strategy: a case of Pulau Panjang, Serang Regency Banten Province

    Science.gov (United States)

    Soejarwo, P. A.; Fitriyanny, W. P.; Heriati, A.; Hakim, A. R.

    2018-03-01

    Due to their high-income contribution, seaweed and grouper aquacultures are important activities in Pulau Panjang community. Determining alternative strategies in developing sustainable aquaculture for seaweed and grouper and their priority factors from theses aquaculture activities are done using TOPSIS and AHP analysis. It was found that the development strategy that must be taken is the option to maintain aquaculture activities, while, environment factor is the highest priority to maintain seaweed and grouper aquaculture in Pulau Panjang. Then three priorities are obtained from environment factor. The first is to maintain the water quality by the growth requirements of seaweed and grouper by encouraging the formation of “Environmental Community Awareness” that involved the active participation of the community to maintain quality and carrying capacity of the environment. Second is to use of natural or artificial coastal protectors (soft structure). The third priority strategy is integration and real implementation of heavy metal pollution control between government, industry sector and society.

  6. Compilation and analysis of national and international OPEX for Safe Enclosure prior to decommissioning

    International Nuclear Information System (INIS)

    Dinner, Paul J.C.; Heimlich, Karel

    2016-01-01

    Around the world, a large number of aging nuclear plants are approaching final shutdown. While this is largely driven by plants reaching the end of their design life, economic factors such as low gas prices (in North America) and the smaller unit size of early commercial reactors are important contributors to this trend. In several instances, economic pressures have resulted in a need for a more rapid transition to Safe Enclosure than originally anticipated. Thus plans for this transition taking into account experience with Safe Enclosure periods of varying lengths are being actively prepared in many jurisdictions. The IAEA as well as other national and international authorities have long recognized the importance of the topic of Safe Enclosure and provided guidance, and the IAEA has recently undertaken a study of 'Lessons Learned from Deferred Decommissioning of Nuclear Facilities'. Beginning with preliminary experience from Canadian CANDU reactors in extended shutdown or safe enclosure, this paper aims to compare this experience with the larger pool of experience from the international community to: - classify the main issues or themes, - examine means to mitigate these, and - formulate general measures of 'good practice'. Compilation of this experience represents the first steps towards a comprehensive, searchable database potentially of use to many in the decommissioning community. Tabulation and analysis of the complete list (comprising approximately 70 cases) has provided the 'short list' of issues presented in Table 1. Examples of the most important listed issues are discussed. The authors' objective is to stimulate interest in extending this compilation. In this way it will continue to grow and benefit all those preparing for transition to decommissioning. (authors)

  7. Compilation and analysis of national and international OPEX or safe enclosure prior to decommissioning

    International Nuclear Information System (INIS)

    Dinner, Paul J.C.; Heimlich, Karel

    2016-01-01

    Around the world, a large number of aging nuclear plants are approaching final shutdown. While this is largely driven by plants reaching the end of their design life, economic factors such as low gas prices (in North America) and the smaller unit size of early commercial reactors are important contributors to this trend. In several instances, economic pressures have resulted in a need for a more rapid transition to Safe Enclosure than originally anticipated. Thus plans for this transition taking into account experience with Safe Enclosure periods of varying lengths are being actively prepared in many jurisdictions. The IAEA as well as other national and international authorities have long recognized the importance of the topic of Safe Enclosure and provided guidance [1-7], and the IAEA has recently undertaken a study of 'Lessons Learned from Deferred Decommissioning of Nuclear Facilities' [8]. Beginning with preliminary experience from Canadian CANDU reactors in extended shutdown or safe enclosure, this paper aims to compare this experience with the larger pool of experience from the international community to: - classify the main issues or themes, - examine means to mitigate these, and - formulate general measures of 'good practice'. Compilation of this experience represents the first steps towards a comprehensive, searchable database potentially of use to many in the decommissioning community. Tabulation and analysis of the complete list (comprising approximately 70 cases) has provided the 'short list' of issues presented. Examples of the most important listed issues are discussed. The authors' objective is to stimulate interest in extending this compilation. In this way it will continue to grow and benefit all those preparing for transition to decommissioning. (authors)

  8. How to measure the economic impacts of changes in growth, feed efficiency and survival in aquaculture

    NARCIS (Netherlands)

    Kankainen, M.; Setala, J.; Berrill, I.K.; Ruohonen, K.; Noble, C.; Schneider, O.

    2012-01-01

    In this article we introduce a variety of bio-economic models that can be used to calculate the economic benefits associated with improved productivity in aquaculture. In the aquaculture industry, three important biological productivity factors are growth, survival and feed efficiency. The

  9. Design and construction of a 76m long-travel laser enclosure for a space occulter testbed

    Science.gov (United States)

    Galvin, Michael; Kim, Yunjong; Kasdin, N. Jeremy; Sirbu, Dan; Vanderbei, Robert; Echeverri, Dan; Sagolla, Giuseppe; Rousing, Andreas; Balasubramanian, Kunjithapatham; Ryan, Daniel; Shaklan, Stuart; Lisman, Doug

    2016-07-01

    Princeton University is upgrading our space occulter testbed. In particular, we are lengthening it to 76m to achieve flightlike Fresnel numbers. This much longer testbed required an all-new enclosure design. In this design, we prioritized modularity and the use of commercial off-the-shelf (COTS) and semi-COTS components. Several of the technical challenges encountered included an unexpected slow beam drift and black paint selection. Herein we describe the design and construction of this long-travel laser enclosure.

  10. Analyzing the environmental impacts of laptop enclosures ...

    Science.gov (United States)

    The market growth of consumer electronics makes it essential for industries and policy-makers to work together to develop sustainable products. The objective of this study is to better understand how to promote environmentally sustainable consumer electronics by examining the use of various materials in laptop enclosures (excluding mounting hardware, internal components, and insulation) using screening-level life cycle assessment. The baseline material, is a fossil plastic blend of polycarbonate-acrylonitrile butadiene styrene. Alternative materials include polylactic acid, bamboo, aluminum, and various combinations of these materials known to be currently used or being considered for use in laptops. The flame retardants considered in this study are bisphenol A bis(diphenyl phosphate), triphenyl phosphate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and borax-boric acid-phosphorous acid. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts v2.1 was used for the assessment of impacts related to climate change, human and ecological health, and resource use. The assessment demonstrates that plastics, relative to the other materials, are currently some of the better performing materials in terms of having the lowest potential environmental impact for a greater number of impact categories based on product life cycle models developed in this study. For fossil plastics, the material performance increases with increasing post-con

  11. Procedure for estimating permanent total enclosure costs

    Energy Technology Data Exchange (ETDEWEB)

    Lukey, M.E.; Prasad, C.; Toothman, D.A.; Kaplan, N.

    1999-07-01

    Industries that use add-on control devices must adequately capture emissions before delivering them to the control device. One way to capture emissions is to use permanent total enclosures (PTEs). By definition, an enclosure which meets the US Environmental Protection Agency's five-point criteria is a PTE and has a capture efficiency of 100%. Since costs play an important role in regulatory development, in selection of control equipment, and in control technology evaluations for permitting purposes, EPA has developed a Control Cost Manual for estimating costs of various items of control equipment. EPA's Manual does not contain any methodology for estimating PTE costs. In order to assist environmental regulators and potential users of PTEs, a methodology for estimating PTE costs was developed under contract with EPA, by Pacific Environmental Services, Inc. (PES) and is the subject of this paper. The methodology for estimating PTE costs follows the approach used for other control devices in the Manual. It includes procedures for sizing various components of a PTE and for estimating capital as well as annual costs. It contains verification procedures for demonstrating compliance with EPA's five-point criteria. In addition, procedures are included to determine compliance with Occupational Safety and Health Administration (OSHA) standards. Meeting these standards is an important factor in properly designing PTEs. The methodology is encoded in Microsoft Exel spreadsheets to facilitate cost estimation and PTE verification. Examples are given throughout the methodology development and in the spreadsheets to illustrate the PTE design, verification, and cost estimation procedures.

  12. Procedure for estimating permanent total enclosure costs

    Energy Technology Data Exchange (ETDEWEB)

    Lukey, M E; Prasad, C; Toothman, D A; Kaplan, N

    1999-07-01

    Industries that use add-on control devices must adequately capture emissions before delivering them to the control device. One way to capture emissions is to use permanent total enclosures (PTEs). By definition, an enclosure which meets the US Environmental Protection Agency's five-point criteria is a PTE and has a capture efficiency of 100%. Since costs play an important role in regulatory development, in selection of control equipment, and in control technology evaluations for permitting purposes, EPA has developed a Control Cost Manual for estimating costs of various items of control equipment. EPA's Manual does not contain any methodology for estimating PTE costs. In order to assist environmental regulators and potential users of PTEs, a methodology for estimating PTE costs was developed under contract with EPA, by Pacific Environmental Services, Inc. (PES) and is the subject of this paper. The methodology for estimating PTE costs follows the approach used for other control devices in the Manual. It includes procedures for sizing various components of a PTE and for estimating capital as well as annual costs. It contains verification procedures for demonstrating compliance with EPA's five-point criteria. In addition, procedures are included to determine compliance with Occupational Safety and Health Administration (OSHA) standards. Meeting these standards is an important factor in properly designing PTEs. The methodology is encoded in Microsoft Exel spreadsheets to facilitate cost estimation and PTE verification. Examples are given throughout the methodology development and in the spreadsheets to illustrate the PTE design, verification, and cost estimation procedures.

  13. High Concentration of Red Clay as an Alternative for Antibiotics in Aquaculture.

    Science.gov (United States)

    Jung, Jaejoon; Jee, Seung Cheol; Sung, Jung-Suk; Park, Woojun

    2016-01-01

    The use of antibiotics in aquaculture raises environmental and food safety concerns because chronic exposure of an aquatic ecosystem to antibiotics can result in the spread of antibiotic resistance, bioaccumulation of antibiotics in the organisms, and transfer of antibiotics to humans. In an attempt to overcome these problems, high-concentration red clay was applied as an alternative antibiotic against the following common fish pathogens: Aeromonas salmonicida, Vibrio alginolyticus, and Streptococcus equinus. The growth of A. salmonicida and V. alginolyticus was retarded by red clay, whereas that of S. equinus was promoted. Phase contrast and scanning electron microscopy analyses confirmed the attachment of red clay on cell surfaces, resulting in rapid gravitational removal and cell surface damage in both A. salmonicida and V. alginolyticus, but not in S. equinus. Different cell wall properties of grampositive species may explain the unharmed cell surface of S. equinus. Significant levels of oxidative stress were generated in only the former two species, whereas significant changes in membrane permeability were found only in S. equinus, probably because of its physiological adaptation. The bacterial communities in water samples from Oncorhynchus mykiss aquacultures supplemented with red clay showed similar structure and diversity as those from oxytetracycline-treated water. Taken together, the antibiotic effects of high concentrations of red clay in aquaculture can be attributed to gravitational removal, cell surface damage, and oxidative stress production, and suggest that red clay may be used as an alternative for antibiotics in aquaculture.

  14. 9 CFR 3.113 - Primary enclosures used to transport marine mammals.

    Science.gov (United States)

    2010-01-01

    ... marine mammals. 3.113 Section 3.113 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION... the animals, their handlers, or other persons. (d) Marine mammals transported in the same primary... used. Within the primary enclosures used to transport marine mammals, the animals will be maintained on...

  15. Measured surface magnetic field attenuation of shielded windows and wire mesh over an electrically small enclosure

    International Nuclear Information System (INIS)

    Hoeft, L.O.; Hofstra, J.S.; Karaskiewicz, R.J.; Wiser, G.

    1984-01-01

    The surface magnetic field attenuation of five types of shielded transparency (window) material was measured over the frequency range 10 kHz to 100 MHz by installing them on an .61 m x .61 m x .2 m enclosure, placing the enclosure on the wall of a TEM cell and measuring the surface and interior magnetic fields using a computer-controlled network analyzer system. The samples included two thicknesses of conductive grids on acrylic, hardware, cloth with 1/8 and 1/4-inch mesh, and a fine mesh laminated optical display window. These measurements are indicative of an enclosure with aperture coupling; namely, they become frequency-independent at high frequencies. Coarse mesh samples (1/8-1/4-inch mesh) were able to provide 50 to 60 dB of magnetic field reduction at tens of MHz, whereas the finer mesh did slightly better. This behavior is consistent with magnetic polarizability theory. Material thickness did not have an appreciable effect for frequencies above a MHz

  16. The influence of finfish aquaculture on benthic fish and crustacean assemblages in Fitzgerald Bay, South Australia

    Directory of Open Access Journals (Sweden)

    Jason E. Tanner

    2015-09-01

    Full Text Available The influence of sea-cage aquaculture on wildfish assemblages has received little attention outside of Europe. Sea-cage aquaculture of finfish is a major focus in South Australia, and while the main species farmed is southern bluefin tuna (Thunnus maccoyii, there is also an important yellowtail kingfish (Seriola lalandi industry. Yellowtail kingfish aquaculture did not appear to have any local or regional effects on demersal assemblages (primarily fish, but also some crustaceans surveyed by baited remote underwater video (BRUV in Fitzgerald Bay. We did, however, detect small scale spatial variations in assemblages within the bay. The type of bait used strongly influenced the assemblage recorded, with significantly greater numbers of fish attracted to deployments where sardines were used as the bait to compared to those with no bait. The pelleted feed used by the aquaculture industry was just as attractive as sardines at one site, and intermediate between sardines and no bait at the other. There was significant temporal variability in assemblages at both farm sites and one control site, while the second control site was temporally stable (over the 9 weeks of the study. Overall, the results suggested that aquaculture was having little if any impact on the abundance and assemblage structure of the demersal macrofauna in Fitzgerald Bay.

  17. Economic Analysis on Key Challenges for Sustainable Aquaculture Development

    DEFF Research Database (Denmark)

    Gedefaw Abate, Tenaw

    challenges that could obstruct its sustainable development, such as a lack of suitable feed, which includes fishmeal, fish oil and live feed, and negative environmental externalities. If the aquaculture industry is to reach its full potential, it must be both environmentally and economically sustainable...... environmental externalities. A sustainable supply of high-quality live feeds at reasonable prices is absolutely essential for aquaculture hatcheries because many commercially produced high-value marine fish larval species, such as flounder, grouper, halibut, tuna and turbot, require live feed for their early...... developmental stage. The key challenge in this regard is that the conventional used live feed items, Artemia and rotifers, are nutritionally deficient. Thus, the first main purpose of the thesis is carrying out an economic analysis of the feasibility of commercial production and the use of an alternative live...

  18. Sound absorption effects in a rectangular enclosure with the foamed aluminum sheet absorber

    International Nuclear Information System (INIS)

    Oh, Jae Eung; Chung, Jin Tai; Kim, Sang Hun; Chung, Kyung Ryul

    1998-01-01

    For the purpose of finding out the optimal thickness of sound absorber and the sound absorption effects due to the selected thickness at an interested frequency range, the analytical study identifies the interior and exterior sound field characteristics of a rectangular enclosure with foamed aluminum lining and the experimental verification is performed with random noise input. By using a two-microphone impedance tube, we measure experimentally the absorption coefficient and the impedance of simple sound absorbing materials. Measured acoustical parameters of the test samples are applied to the theoretical analysis to predict sound pressure field in the cavity. The sound absorption effects from measurements are compared to predicted ones in both cases with and without foamed aluminum lining in the cavity of the rectangular enclosure

  19. Evaluation of Internalisation Processes in Environmental Management Systems: Aquaculture and Offshore Mussel Farming

    OpenAIRE

    Malorgio, Giulio

    2005-01-01

    In recent years, particular attention has been paid to fishing activities, and more specifically to aquaculture, a production process whose environmental impact at present is not being adequately submitted to any sort of serious assessment and control. The impact of aquaculture on the environment has nonetheless become an important issue for both potential customers and public opinion. The purpose of this study is to appraise environmental protection costs if and when a certified program of e...

  20. Does the Recent Growth of Aquaculture Create Antibiotic Resistance Threats Different from those Associated with Land Animal Production in Agriculture?

    Science.gov (United States)

    Done, Hansa Y; Venkatesan, Arjun K; Halden, Rolf U

    2015-05-01

    Important antibiotics in human medicine have been used for many decades in animal agriculture for growth promotion and disease treatment. Several publications have linked antibiotic resistance development and spread with animal production. Aquaculture, the newest and fastest growing food production sector, may promote similar or new resistance mechanisms. This review of 650+ papers from diverse sources examines parallels and differences between land-based agriculture of swine, beef, and poultry and aquaculture. Among three key findings was, first, that of 51 antibiotics commonly used in aquaculture and agriculture, 39 (or 76%) are also of importance in human medicine; furthermore, six classes of antibiotics commonly used in both agriculture and aquaculture are also included on the World Health Organization's (WHO) list of critically important/highly important/important antimicrobials. Second, various zoonotic pathogens isolated from meat and seafood were observed to feature resistance to multiple antibiotics on the WHO list, irrespective of their origin in either agriculture or aquaculture. Third, the data show that resistant bacteria isolated from both aquaculture and agriculture share the same resistance mechanisms, indicating that aquaculture is contributing to the same resistance issues established by terrestrial agriculture. More transparency in data collection and reporting is needed so the risks and benefits of antibiotic usage can be adequately assessed.

  1. Chemical and Sensory Quantification of Geosmin and 2-Methylisoborneol in Rainbow Trout (Oncorhynchus mykiss) from Recirculated Aquacultures in Relation to Concentrations in Basin Water

    DEFF Research Database (Denmark)

    Petersen, Mikael A.; Hyldig, Grethe; Strobel, Bjarne W.

    2011-01-01

    Globally, aquaculture systems with water recirculation experience increasing problems with microbial taste and odor compounds (TOCs) such as geosmin and 2-methylisoborneol (MIB). This study investigated the content of geosmin and MIB in water and the flesh of 200 rainbow trouts from eight...... recirculated aquaculture systems in Denmark. TOC content in the fish flesh was measured by a dynamic headspace extraction method and was evaluated by a sensory panel. The results showed significant correlations between TOC content in water and fish and between chemical analysis and sensory perception. When...... geosmin exceeded 20 ng/L in the water, 96% of the fish had an intense muddy flavor, but below 10 ng geosmin/L, 18% of the fish (only 3% in special depuration ponds) had an intense muddy flavor. The results indicate that TOC levels...

  2. Bioethical Considerations of Advancing the Application of Marine Biotechnology and Aquaculture.

    Science.gov (United States)

    Harrell, Reginal M

    2017-06-24

    Normative ethical considerations of growth of the marine biotechnology and aquaculture disciplines in biopharming, food production, and marine products commercialization from a bioethical perspective have been limited. This paucity of information begs the question of what constitutes a bioethical approach (i.e., respect for individuals or autonomy; beneficence, nonmaleficence, and justice) to marine biotechnology and aquaculture, and whether it is one that is appropriate for consideration. Currently, thoughtful discussion on the bioethical implications of use, development, and commercialization of marine organisms or their products, as well as potential environmental effects, defaults to human biomedicine as a model. One must question the validity of using human bioethical principlism moral norms for appropriating a responsible marine biotechnology and aquaculture ethic. When considering potential impacts within these disciplines, deference must be given to differing value systems in order to find common ground to advance knowledge and avoid emotive impasses that can hinder the science and its application. The import of bioethical considerations when conducting research and/or production is discussed. This discussion is directed toward applying bioethical principles toward technology used for food, biomedical development (e.g., biopharming), or as model species for advancement of knowledge for human diseases.

  3. Linked sustainability challenges and trade-offs among fisheries, aquaculture and agriculture.

    Science.gov (United States)

    Blanchard, Julia L; Watson, Reg A; Fulton, Elizabeth A; Cottrell, Richard S; Nash, Kirsty L; Bryndum-Buchholz, Andrea; Büchner, Matthias; Carozza, David A; Cheung, William W L; Elliott, Joshua; Davidson, Lindsay N K; Dulvy, Nicholas K; Dunne, John P; Eddy, Tyler D; Galbraith, Eric; Lotze, Heike K; Maury, Olivier; Müller, Christoph; Tittensor, Derek P; Jennings, Simon

    2017-09-01

    Fisheries and aquaculture make a crucial contribution to global food security, nutrition and livelihoods. However, the UN Sustainable Development Goals separate marine and terrestrial food production sectors and ecosystems. To sustainably meet increasing global demands for fish, the interlinkages among goals within and across fisheries, aquaculture and agriculture sectors must be recognized and addressed along with their changing nature. Here, we assess and highlight development challenges for fisheries-dependent countries based on analyses of interactions and trade-offs between goals focusing on food, biodiversity and climate change. We demonstrate that some countries are likely to face double jeopardies in both fisheries and agriculture sectors under climate change. The strategies to mitigate these risks will be context-dependent, and will need to directly address the trade-offs among Sustainable Development Goals, such as halting biodiversity loss and reducing poverty. Countries with low adaptive capacity but increasing demand for food require greater support and capacity building to transition towards reconciling trade-offs. Necessary actions are context-dependent and include effective governance, improved management and conservation, maximizing societal and environmental benefits from trade, increased equitability of distribution and innovation in food production, including continued development of low input and low impact aquaculture.

  4. Bioethical Considerations of Advancing the Application of Marine Biotechnology and Aquaculture

    Directory of Open Access Journals (Sweden)

    Reginal M. Harrell

    2017-06-01

    Full Text Available Normative ethical considerations of growth of the marine biotechnology and aquaculture disciplines in biopharming, food production, and marine products commercialization from a bioethical perspective have been limited. This paucity of information begs the question of what constitutes a bioethical approach (i.e., respect for individuals or autonomy; beneficence, nonmaleficence, and justice to marine biotechnology and aquaculture, and whether it is one that is appropriate for consideration. Currently, thoughtful discussion on the bioethical implications of use, development, and commercialization of marine organisms or their products, as well as potential environmental effects, defaults to human biomedicine as a model. One must question the validity of using human bioethical principlism moral norms for appropriating a responsible marine biotechnology and aquaculture ethic. When considering potential impacts within these disciplines, deference must be given to differing value systems in order to find common ground to advance knowledge and avoid emotive impasses that can hinder the science and its application. The import of bioethical considerations when conducting research and/or production is discussed. This discussion is directed toward applying bioethical principles toward technology used for food, biomedical development (e.g., biopharming, or as model species for advancement of knowledge for human diseases.

  5. Occurrence of tetracycline resistance genes in aquaculture facilities with varying use of oxytetracycline

    Science.gov (United States)

    Seyfried, Erin E.; Newton, Ryan J.; Rubert, Kennedy F.; Pedersen, Joel A.; McMahon, Katherine D.

    2014-01-01

    The contribution of human activities to environmental reservoirs of antibiotic resistance is poorly understood. The purpose of this study was to determine if oxytetracycline (OTC) use in aquaculture facilities increased the detection frequency (i.e. prevalence) of tetracycline resistance genes relative to facilities with no recent OTC treatment. We used PCR to screen water and sediment from four non-commercial fish farms in northwestern Wisconsin for the presence of ten tetracycline resistance determinants (tetR): tet(A), tet(B), tet(D), tet(E), tet(G), tet(M), tet(O), tet(Q), tet(S) and tet(W). Water from farms with recent OTC use had significantly higher tetR detection frequencies than did water from farms without recent OTC use, with prevalence in raceways and rearing ponds of farms with recent OTC use exceeded by more than two-fold that of farms not using OTC. Effluent from all farms, regardless of treatment regime, had higher tetR detection frequencies than their corresponding influent for all genes, but the specific combinations of tetR genes detected in a sample were not different from their corresponding influent. Although OTC use was associated with the increased occurrence and diversity of tetR genes in water samples, it was not found to relate to tetR gene occurrence in sediment samples. Sediment samples from facilities with no recent OTC use had significantly higher frequencies of tetR gene detection than did samples from facilities with recent OTC use. All of the tetR genes were detected in both the medicated and non-medicated feed samples analyzed in this study. These findings suggest that both OTC treatment in aquaculture facilities, and the farms themselves, may be sources of tetR gene introduction to the environment. To our knowledge, this is the first study to use genotypic and cultivation-independent methods to examine tetR gene occurrence associated with OTC use in aquaculture. PMID:20217406

  6. Interactions between piscivores, zooplanktivores and zooplankton in submerged macrophytes : Preliminary observations from enclosure and pond experiments

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Perrow, M.R.; Landkildehus, F.

    1997-01-01

    behavioural changes of zooplanktivores has received little attention, even though this may be an important mechanism in enhancing the stability of submerged macrophytes in shallow lakes. Preliminary observations from an unreplicated large-scale field enclosure experiment and a replicated pond experiment...... and the presence of zooplanktivores typically changed the habitat selection of cladoceran zooplankton. In the case of piscivore/zooplanktivore interactions, the risk of predation was enough to generate clear responses even where the losses to predation were low. However, only in the enclosure experiment...

  7. New aquaculture drugs under FDA review

    Science.gov (United States)

    Bowker, James D.; Gaikowski, Mark P.

    2012-01-01

    Only eight active pharmaceutical ingredients available in 18 drug products have been approved by the U.S. Food and Drug Administration for use in aquaculture. The approval process can be lengthy and expensive, but several new drugs and label claims are under review. Progress has been made on approvals for Halamid (chloramine-T), Aquaflor (florfenicol) and 35% PeroxAid (hydrogen peroxide) as therapeutic drugs. Data are also being generated for AQUI-S 20E, a fish sedative.

  8. Analysis of nutrient flows in integrated intensive aquaculture systems

    NARCIS (Netherlands)

    Schneider, O.; Sereti, V.; Eding, E.H.; Verreth, J.A.J.

    2005-01-01

    This paper analyses nutrient conversions, which are taking place in integrated intensive aquaculture systems. In these systems fish is cultured next to other organisms, which are converting otherwise discharged nutrients into valuable products. These conversions are analyzed based on nitrogen and

  9. Toxicity of three antibiotics used in aquaculture on the marine microalgae Tetraselmis suecica (Kylin Butch.

    Directory of Open Access Journals (Sweden)

    Marta Seoane

    2014-06-01

    Full Text Available Aquaculture facilities are a potential source of antibiotics to the aquatic ecosystems. The presence of these compounds in the environment may have deleterious effects on non-target aquatic organisms such as microalgae, which are often used as biological indicators of pollution. Therefore, the aim of the present study was to evaluate the toxicity induced by chloramphenicol (CHL, florfenicol (FLO and oxytetracycline (OTC, three antibiotics widely used in aquaculture, on the marine microalgae Tetraselmis suecica, a species also used in aquacultural practices. Toxicity was evaluated taking into account alterations on growth and cellular viability and activity, being these parameters monitored using flow cytometry technique. Results showed that all three antibiotics assayed inhibit growth of T. suecica with 96 h IC50 values of 11.16, 9.03 and 17.25 mg l-1 for CHL, FLO and OTC, respectively. After 24 hours of exposure, the integrity of the cell membrane, related with cellular viability and assessed by propidium iodide staining (PI, was not altered; therefore cells remained viable. However, FLO and OTC were found to significant reduce the metabolic activity at higher concentrations assayed, as indicated the fluorescein diacetate assay (FDA. Since growth inhibition and significant physiological alterations were observed, it can be concluded that T. suecica was sensitive to the three antibiotics tested, thus the use of these antibiotics should be carefully monitored to reduce the potential risk of contamination of the marine environment.

  10. Moisture ingress into electronics enclosures under isothermal conditions

    DEFF Research Database (Denmark)

    Staliulionis, Zygimantas; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    loads are still not understood well by design engineers, therefore this field has become one of the bottlenecks in the electronics system design. The objective of this paper is to model moisture ingress into an electronics enclosure under isothermal conditions. The moisture diffusion model is based......The number of electronics used in outdoor environment is constantly growing. The humidity causes about 19 % of all electronics failures and, especially, moisture increases these problems due to the ongoing process of miniaturization and lower power consumption of electronic components. Moisture...

  11. A SWOT analysis of aquaculture development in rural areas of Iran, an application to Rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Roxana Moogouei

    2014-03-01

    Full Text Available In this study various important indices were selected to assess the sustainable aquaculture strategies in rural areas of Iran. In addition the government officials, consultants and managers were surveyed to assess the indices of aquaculture development. The strengths, weaknesses, opportunities and threats   analyses were used to make a comprehensive evaluation on internal and external factors, participating the development of aquaculture strategies. The sum of the attractiveness scores from the Internal Factor Evaluation Matrix was approximately 2.55, being larger than 2.5, indicating that the strengths exceed the weaknesses. The sum of the External Factor Evaluation Matrix scores was 3.49, indicating that opportunities were higher than threats. This analysis showed that the development of aquaculture, promotion of new cold-water species production, productivity enhancement, establishment of hatchery facilities and formation of an effective support organization are the most important strategies that should be considered in the studied area. Results obtained on this research help decision makers on work of the aquaculture sector in rural areas of Iran.

  12. 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.

  13. Sea cucumbers reduce chromophoric dissolved organic matter in aquaculture tanks

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Sadeghi-Nassaj

    2018-02-01

    being similar to those found in the inlet waters (average: 0.32 m−1 and 22 µm−1, respectively. This reduction in the absorption of the dissolved organic matter appears to be mediated by the POM consumption by holothurians. The experiments confirmed the results observed in the time-series. The a325 and S275−295 values were significantly lower in the treatment with holothurians than in the treatment without holothurians indicating a reduction in the concentration of chromophoric organic compounds, particularly of low molecular weight. Discussion Consequently, sea cucumbers appear to improve water transparency in aquaculture tanks. The underlying mechanism of this improvement might be related to the POM consumption by holothurians, which reduces the concentration of CDOM derived from POM disaggregation or to the direct assimilation of dissolved compounds of low molecular weight as chromophoric amino acids.

  14. 9 CFR 112.2 - Final container label, carton label, and enclosure.

    Science.gov (United States)

    2010-01-01

    ... carton; (10) In the case of a product which contains an antibiotic added during the production process... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Final container label, carton label, and enclosure. 112.2 Section 112.2 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION...

  15. 9 CFR 3.87 - Primary enclosures used to transport nonhuman primates.

    Science.gov (United States)

    2010-01-01

    ... nonhuman primates. 3.87 Section 3.87 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE..., and Transportation of Nonhuman Primates 2 Transportation Standards § 3.87 Primary enclosures used to transport nonhuman primates. Any person subject to the Animal Welfare regulations (9 CFR parts 1, 2, and 3...

  16. Dissolved oxygen and aeration in ictalurid catfish aquaculture

    Science.gov (United States)

    Feed-based production of ictalurid catfish in ponds is the largest aquaculture sector in the United States. The feed biochemical oxygen demand (FBOD) typically is 1.1-1.2 kg O2/kg feed. Feed also results in a substantial increase of carbon dioxide, ammonia nitrogen, and phosphate to ponds, and this ...

  17. Coral aquaculture: applying scientific knowledge to ex situ production

    NARCIS (Netherlands)

    Leal, M.C.; Ferrier-Pagès, C.; Petersen, D.; Osinga, R.

    2016-01-01

    Coral aquaculture is an activity of growing interest due to the degradation of coral reefs worldwide and concomitant growing demand for corals by three industries: marine ornamental trade, pharmaceutical industry and reef restoration. Although captive breeding and propagation of corals is a

  18. Numerical Investigation of the Effect of Magnetic Field on Natural Convection in a Curved-Shape Enclosure

    Directory of Open Access Journals (Sweden)

    M. Sheikholeslami

    2013-01-01

    Full Text Available This investigation reports the magnetic field effect on natural convection heat transfer in a curved-shape enclosure. The numerical investigation is carried out using the control volume-based-finite element method (CVFEM. The numerical investigations are performed for various values of Hartmann number and Rayleigh number. The obtained results are depicted in terms of streamlines and isotherms which show the significant effects of Hartmann number on the fluid flow and temperature distribution inside the enclosure. Also, it was found that the Nusselt number decreases with an increase in the Hartmann number.

  19. Treatment of turtle aquaculture effluent by an improved multi-soil-layer system.

    Science.gov (United States)

    Song, Ying; Huang, Yu-ting; Ji, Hong-fang; Nie, Xin-jun; Zhang, Zhi-yuan; Ge, Chuan; Luo, An-cheng; Chen, Xin

    2015-02-01

    Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer (MSL) systems treating turtle aquaculture effluent with adding different amounts of sludge. Four MSL systems were constructed with dry weight ratios of sludge with 0%, 5%, 10%, and 20% (MSL 1, MSL 2, MSL 3, and MSL 4, respectively). The turtle aquaculture effluent had an average chemical oxygen demand (COD), ammonia nitrogen (NH4(+)-N) and total nitrogen (TN) concentration of 288.4, 213.4, and 252.0 mg/L, respectively. The COD/TN (C/N) ratio was 1.2. The results showed that the four MSL systems could effectively treat the COD, NH4(+)-N, and TN, and MSL 4 showed significantly improved NH4(+)-N removal efficiency, suggesting the potential of sludge addition to improve the turtle aquaculture effluent treatment. The average COD, TN, and NH4(+)-N removal efficiencies of MSL 4 were 70.3%, 66.5%, and 72.7%, respectively. To further interpret the contribution of microorganisms to the removal, the microbial community compositions and diversities of the four MSL systems were measured. Comparisons of the denaturing gradient gel electrophoresis (DGGE) profiles revealed that the amount of nitrifying bacteria and diversity in MSL 4 were higher than those in the other three systems. We concluded that adding 20% of sludge improved the NH4(+)-N removal and stability of the system for nitrification, due to the enrichment of the nitrifying bacteria in MSL 4.

  20. Current status of parasitic ciliates Chilodonella spp. (Phyllopharyngea: Chilodonellidae) in freshwater fish aquaculture.

    Science.gov (United States)

    Bastos Gomes, G; Jerry, D R; Miller, T L; Hutson, K S

    2017-05-01

    Freshwater fish farming contributes to more than two-thirds of global aquaculture production. Parasitic ciliates are one of the largest causes of production loss in freshwater farmed fishes, with species from the genus Chilodonella being particularly problematic. While Chilodonella spp. include 'free-living' fauna, some species are involved in mortality events of fish, particularly in high-density aquaculture. Indeed, chilodonellosis causes major productivity losses in over 16 species of farmed freshwater fishes in more than 14 countries. Traditionally, Chilodonella species are identified based on morphological features; however, the genus comprises yet uncharacterized cryptic species, which indicates the necessity for molecular diagnostic methods. This review synthesizes current knowledge on the biology, ecology and geographic distribution of harmful Chilodonella spp. and examines pathological signs, diagnostic methods and treatments. Recent advances in molecular diagnostics and the ability to culture Chilodonella spp. in vitro will enable the development of preventative management practices and sustained freshwater fish aquaculture production. © 2016 John Wiley & Sons Ltd.

  1. Environmental impact analysis of aquaculture in net cages in a ...

    African Journals Online (AJOL)

    Environmental impact analysis of aquaculture in net cages in a Brazilian water reservoir, based in zooplankton communities. Maria Cristina Crispim, Karla Patrícia Ponte Araújo, Hênio do Nascimento Melo Júnior ...

  2. Efficiency of Different Integrated Agriculture Aquaculture Systems in the Red River Delta of Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen Van Huong

    2018-02-01

    Full Text Available Integrated Agriculture Aquaculture (IAA is characteristic with diversity of small-scale production systems in the Red River Delta, Vietnam where most integrated aquaculture systems are closely associated to the VAC model, an ecosystem production that three components: garden (V, pond (A and livestock pen (C are integrated. These VAC systems effectively use all the available land, air, water and solar energy resources, and also effectively recycle by-products and waste for providing diversified agricultural products to meet the complex nutritional demands of rural communities. The IAA systems are dynamic, diverse and subject to economic and environmental changes. By investigating 167 aquaculture households, the traditional VAC, New VAC, Animal Fish (AF and Commercial Fish (FS systems are identified as four existing IAA systems. This paper presents the main characteristics and economic efficiency of these IAA systems. The study’s results indicate clear evidence that the traditional VAC system and New VAC system are the most efficient and effective models. The findings of this study have shed light on the important role of integrated aquaculture systems to food security and economic development of households and local communities. The VAC systems are likely to propose for improving household food security and developing the local economy.

  3. Design and Development of Smart Aquaculture System Based on IFTTT Model and Cloud Integration

    Directory of Open Access Journals (Sweden)

    Dzulqornain Muhammad Iskandar

    2018-01-01

    Full Text Available The internet of things technology (IoT is growing very rapidly. IoT implementation has been conducted in several sectors. One of them is for aquaculture. For the traditional farmers, they face problems for monitoring water quality and the way to increase the quality of the water quickly and efficiently. This paper presents a real-time monitoring and controlling system for aquaculture based on If This Then That (IFTTT model and cloud integration. This system was composed of smart sensor module which supports modularity, smart aeration system for controlling system, local network system, cloud computing system and client visualization data. In order to monitor the water condition, we collect the data from smart sensor module. Smart sensor module consists of sensor dissolved oxygen, potential of hydrogen, water temperature and water level. The components of smart aeration system are microcontroller NodeMCU v3, relay, power supply, and propeller that can produce oxygen. The system could set the IFTTT rules for the ideal water condition for the pond in any kinds of aquaculture based on its needs through the web and android application. The experimental result shows that use IFTTT model makes the aquaculture monitoring system more customizable, expandable and dynamic.

  4. Mathematical modelling of coupled heat and mass transport into an electronic enclosure

    DEFF Research Database (Denmark)

    Staliulionis, Zygimantas; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    In contrast to high fidelity CFD codes which require higher computational effort/time, the well-known Resistor-Capacitor (RC) approach requires much lower calculation time, but also with a lower resolution of the geometrical arrangement. Therefore, for enclosures without too complex geometry...

  5. Surveillance and Maintenance Plan for the 105-C Reactor Safe Storage Enclosure

    International Nuclear Information System (INIS)

    Logan, T. E.

    1998-01-01

    This document provides a plan for implementing surveillance and maintenance activities to ensure that the 105-C Reactor Safe Storage Enclosure is maintained in a safe, environmentally secure, and cost-effective manner until subsequent closure during the final disposition phase of decommissioning

  6. Analysis of economic and energy utilization aspects for waste heat aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.; Wilson, J. V.

    1978-01-01

    A waste heat aquaculture system using extensive culture techniques to produce fin and shellfish is currently under investigation at the Oak Ridge National Laboratory. The system uses nutrients in waste water streams to grow algae and zooplankton which are fed to fish and clams. A tilapia polyculture association and the freshwater clam Corbicula are the animals cultured in the system. The investigations were performed to determine the economic feasibility of the system and examine energy utilization in the system. A net energy analysis was performed to identify the energy saving potential for the system. This analysis includes all energy costs (both direct and indirect) associated with building and operating the system. The results of the economic study indicated that fish production costs of $0.55/kg ($0.25/lb) were possible. This cost, however, depends upon the fish production rate and food conversion efficiency and could rise to as much as $1.65/kg ($0.75/lb). Clam production costs were found to be in the neighborhood of $0.37/kg of clam meat ($1.24/bushel). The energy utilization study results indicated that, when all energy costs are included, fish from the aquaculture system may require only 35% of the net energy now required for fish products from the ocean. However, the energy requirements also depend on system parameters and could be as large as the energy required for ocean caught products. Clams can be produced in the aquaculture system using only about 25% of the net energy required by traditional means. The results of the analysis indicate that the system appears to be economically feasible. They also indicate that significant energy savings are possible if waste heat aquaculture products replace ocean caught products.

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

    DEFF Research Database (Denmark)

    Prehn, Jonas; Waul, Christopher Kevin; Pedersen, Lars-Flemming

    2012-01-01

    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 det...... 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......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...

  8. 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

    on a daily basis as compared to untreated systems. In systems intermittently treated with formalin, increased variation and minor reductions of ammonium and nitrite oxidation rates were observed. Nitrifying bacteria were screened by specific gene probes using fluorescence in situ hybridization and quantified...... 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...

  9. MHD mixed convection flow and heat transfer in an open C-shaped enclosure using water-copper oxide nanofluid

    Science.gov (United States)

    Armaghani, T.; Esmaeili, H.; Mohammadpoor, Y. A.; Pop, I.

    2018-01-01

    In this paper, the steady mixed convection flow and heat transfer of water-copper oxide nanofluid in an open C-shaped enclosure is investigated numerically. The enclosure is under constant magnetic field. Effects of Richardson number, magnetic and nanofluid volume fraction parameters are studied and discussed. The nanofluid with a cold temperature of T C and a velocity of u c enters the enclosure from the top right corner and exits from the bottom right corner. The vertical wall of the left side is subjected to a hot and constant temperature T h . Also, other walls are insulated. It is found that the heat transfer is increased via increasing the Hartmann and Reynolds numbers. For low Reynolds numbers, the enhances of the Hartman number leads to a slightly increases of the average Nusselt number, but for high Reynolds numbers, the average Nusselt number gets an ascending trend and the increase in the Hartmann number shows its effect more pronounced. Also, with increase in Ri, the effect of nanofluid on the heat transfer increases. Due to practical impotence, the study of mixed convection heat transfer in enclosures and various shaped of cavities has attracted remarkable attentions in the past few decades. Significant applications of the mixed convection flow can be found in atmospheric flows, solar energy storage, heat exchangers, lubrication technology, drying technologies, cooling of the electronic devices, etc. The present results are original and new for the problem of MHD mixed convection flow and heat transfer in an open C-shaped enclosure using water-copper oxide nanofluid. Comparison of the obtained results with those from the open literature (Mahmoodi et al. [24]) is acceptable.

  10. Economic Feasibility of Recirculating Aquaculture Systems in Pangasius Farming

    NARCIS (Netherlands)

    Pham, T.A.N.; Gielen-Meuwissen, M.P.M.; Le, T.C.; Verreth, J.A.J.; Bosma, R.H.; Oude Lansink, A.G.J.M.

    2016-01-01

    This study aims to analyze the economic feasibility of recirculating aquaculture systems (RAS) in pangasius farming in Vietnam. The study uses a capital budgeting approach and accounts for uncertainty in key parameters. Stochastic simulation is used to simulate the economic performance of medium and

  11. A numerical study on buoyancy-driven flow in an inclined square enclosure heated and cooled on adjacent walls

    International Nuclear Information System (INIS)

    Aydin, O.; Uenal, A.; Ayhan, T.

    1999-01-01

    Buoyancy-driven flows in enclosures play a vital role in many engineering applications such as double glazing, ventilation of rooms, nuclear reactor insulation, solar energy collection, cooling of electronic components, and crystal growth in liquids. Here, numerical study on buoyancy-driven laminar flow in an inclined square enclosure heated from one side and cooled from the adjacent side is conducted using finite difference methods. The effect of inclination angle on fluid flow and heat transfer is investigated by varying the angle of inclination between 0 degree and 360degree, and the results are presented in the form of streamlines and isotherms for different inclination angles and Rayleigh numbers. On the basis of the numerical data, the authors determine the critical values of the inclination angle at which the rate of the transfer within the enclosure is either maximum or minimum

  12. Proximate analyses - Utilization of Marine Process Waste for Aquaculture Feeds

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Limited amounts of forage fish are available as an ingredient in feeds for the expanding aquaculture industry. Work is being conducted on a variety of underutilized...

  13. Merging remotely sensed data, models and indicators for a sustainable development of coastal aquaculture in Algeria

    Science.gov (United States)

    Brigolin, Daniele; Venier, Chiara; Amine Taji, Mohamed; Lourguioui, Hichem; Mangin, Antoine; Pastres, Roberto

    2014-05-01

    Finfish cage farming is an economically relevant activity, which exerts pressures on coastal systems and thus require a science-based management, based on the Ecosystem Approach, in order to be carry out in a sustainable way. Within MEDINA project (EU 282977), ocean color data and models were used for estimating indicators of pressures of aquaculture installations along the north African coast. These indicators can provide important support for decision makers in the allocation of new zones for aquaculture, by taking into account the suitability of an area for this activity and minimizing negative environmental effects, thus enhancing the social acceptability of aquaculture. The increase in the number of farms represents a strategic objective for the Algerian food production sector, which is currently being supported by different national initiatives. The case-study presented in this work was carried out in the Gulf of Bejaia. Water quality for aquaculture was first screened based on ocean color CDOM data (http://www.globcolour.info/). The SWAN model was subsequently used to propagate offshore wave data and to derive wave height statistics. On this basis, sub-areas of the Gulf were ranked, according their optimality in respect to cage resistance and fish welfare requirements. At the three best sites an integrated aquaculture impact assessment model was therefore applied: this tool allows one to obtain a detailed representation of fish growth and population dynamics inside the rearing cages, and to simulate the deposition of uneaten food and faeces on the sediment and the subsequent mineralization of organic matter. This integrated model was used to produce a set of indicators of the fish cages environmental interaction under different scenarios of forcings (water temperature, feeding, currents). These model-derived indicators could usefully contribute to the implementation of the ecosystem approach for the management of aquaculture activities, also required by the

  14. Antibiotic resistance profile of Pseudomonas aeruginosa isolated from aquaculture and abattoir environments in urban communities

    Directory of Open Access Journals (Sweden)

    Isoken Henrietta Igbinosa

    2017-01-01

    Full Text Available Objective: To characterize multiple antibiotic resistance profile of Pseudomonas aeruginosa from aquaculture and abattoir environments. Methods: Wastewater samples were obtained from the abattoir and aquaculture environments between May 2016 and July 2016 and analysed using standard phenotypic, biochemical and PCR-based methods. Results: The mean pseudomonads count ranged from (4 × 102 ± 1.01 to (2 × 104 ± 0.10 colony-forming unit/mL in the aquaculture environment and (3 × 103 ± 0.00 to (1 × 105 ± 1.00 colony-forming unit/mL in the abattoir environment. A total of 96 isolates of Pseudomonas aeruginosa confirmed by PCR were thereafter selected from both aquaculture and abattoir environments and further characterized for their antimicrobial susceptibility profile by adopting the disc diffusion method. High level of resistance was observed against the aminoglycosides [gentamycin 64/96 (66.67% and kanamycin 52/96 (54.17%], monobactams [aztreonam 76/96 (79.17%], carbapenems [meropenem 52/96 (54.17%], tetracyclines [tetracycline 72/96 (75.00%] and cephems [ceftazidime 72/96 (75.00% and cefuroxime 48/96 (50.00%]. Multiple antibiotic resistant index of the respective isolates ranged from 0.4 to 0.8 while multidrug resistant profile of the isolates revealed that 28 of the respective isolates were resistant to ceftazidime, cefuroxime, gentamycin, kanamycin, aztreonam which belongs to cephems, aminoglycosides and monobactam class of antimicrobials. Conclusions: Findings from the present study therefore underscores the need for effective monitoring of the abattoir and aquaculture environments as they could be the significant source for spreading antibiotic resistant bacteria within the environment.

  15. Investigating opportunities to support indigenous aquaculture in Australia : Visit to Kimberley, Western Australia, May 2003

    OpenAIRE

    Haylor, G.

    2003-01-01

    The STREAM Initiative has been working with issues relating to livelihoods, policy and institutional development and communications throughout Asia-Pacific. Recently this has included work in India with indigenous communities supporting people to have a voice in policy making processes. There appear to be some parallels between this work and the objectives of Kimberley Aquaculture Aboriginal Corporation (KAAC) and also the Agriculture Fisheries and Forestry Australia (AFFA) Indigenous Aqua...

  16. Manual on the production and use of live food for aquaculture

    National Research Council Canada - National Science Library

    Lavens, P; Sorgeloos, Patrick

    1996-01-01

    .... The manual is divided into different sections according to the major groups of live food organisms used in aquaculture, namely micro-algae, rotifers, Artemia, natural zooplankton, and copepods...

  17. Aquaculture and feeding ecology: Feeding behaviour in turbot larvae

    DEFF Research Database (Denmark)

    Bruno, Eleonora

    capture success. This thesis is part of a large international project aimed at improving the rearing techniques of high value fish species larvae fed with calanoid copepods, their natural prey, to achieve high levels of survival and quality. In fact, fish aquaculture is becoming increasingly important...

  18. Aquaculture: a promising solution for food insecurity, poverty and ...

    African Journals Online (AJOL)

    With increasing food production challenges such as dwindling capture fisheries and impacts of climate change becoming more eminent, solutions to food insecurity and malnutrition in Kenya must bring about quick results in food availability by stimulating more own-food production. Aquaculture has so far been recognized ...

  19. Comments on the current status of aquaculture in heated effluents in North America

    International Nuclear Information System (INIS)

    Ayles, G.B.

    1976-01-01

    At the current rate of increase the world demand for fish protein will soon far exceed the supply. The culture of aquatic organisms in low-grade waste heat could be a significant source of animal protein. There are at present thriving trout culture and catfish culture industries in North America. There are a number of small-scale research and commercial aquaculture projects currently in operation and numerous studies have been carried out. However, the knowledge gained has not had a significant impact on waste heat aquaculture development. (author)

  20. A Monitoring and Control System for Aquaculture via Wireless Network and Android Platform

    Directory of Open Access Journals (Sweden)

    Juan Huan

    2014-04-01

    Full Text Available Web applications, databases and advanced mobile platform can facilitate real-time data acquisition for effective monitoring on intelligent agriculture. To improve facilities for aquaculture production automation and efficient, this paper presents an application for wireless network and Android platform that interacts with an advanced control system based on Apache, SQL Server, Java, to collect and monitor variables applied in aquaculture. The test and application shows that is stable, high price-performance ratio, good mobility and easy to operate, It has a strong practicality and application prospects.