WorldWideScience

Sample records for greenhouse aquaculture raceway

  1. 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.

  2. Development of Efficient Sludge Collection Cones for Concentration of Raceway-Derived Solids in Recirculating Aquaculture Systems

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Laursen, Jesper; McLean, E

    2004-01-01

    The efficiency of sludge cones in raceways was studied using both physical and computational fluid dynamics (CFD) models. A sludge cone installed at a commercial trout farm was used as a model for the experiments. A scale 1:4 model of the commercial cone was constructed. In order to describe flui...... removal but will also reduce water loss....

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

    Science.gov (United States)

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

    2014-02-01

    Aquaculture is one of the fastest-growing segments of the food economy in modern times. It is also being considered as an important source of greenhouse gas (GHG) emissions. To date, limited studies have been conducted on GHG emissions from aquaculture system. In this study, daily addition of fish feed and soluble starch at a carbon-to-nitrogen (C/N) ratio of 16:1 (w/w) was used to examine the effects of carbohydrate addition on nitrogen transformations and GHG emissions in a zero-water exchange intensive aquaculture system. The addition of soluble starch stimulated heterotrophic bacterial growth and denitrification, which led to lower total ammonia nitrogen, nitrite and nitrate concentrations in aqueous phase. About 76.2% of the nitrogen output was emitted in the form of gaseous nitrogen (i.e., N2 and N2O) in the treatment tank (i.e., aquaculture tank with soluble starch addition), while gaseous nitrogen accounted for 33.3% of the nitrogen output in the control tank (i.e., aquaculture tank without soluble starch addition). Although soluble starch addition reduced daily N2O emissions by 83.4%, it resulted in an increase of daily carbon dioxide (CO2) emissions by 91.1%. Overall, starch addition did not contribute to controlling the GHG emissions from the aquaculture system. © 2013.

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

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

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

  5. International blast furnace hearth and raceway symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Papers presented discussed some of the physical and chemical processes occuring in the raceway and hearths of blast furnaces. The injection of coal or fuel slurries to replace some of the coke was also covered. Fourteen papers are abstracted separately.

  6. Tool Indicates Contact Angles In Bearing Raceways

    Science.gov (United States)

    Akian, Richard A.; Butner, Myles F.

    1995-01-01

    Tool devised for use in measuring contact angles between balls and races in previously operated ball bearings. Used on both inner and outer raceways of bearings having cross-sectional widths between approximately 0.5 and 2.0 in. Consists of integral protractor mounted in vertical plane on bracket equipped with leveling screws and circular level indicator. Protractor includes rotatable indicator needle and set of disks of various sizes to fit various raceway curvatures.

  7. Greenhouse gas emissions associated with direct energy inputs for a warmwater low-salinity recirculating aquaculture systems

    Science.gov (United States)

    Greenhouse gases (GHGs) are gases that trap heat in the atmosphere. These gases include carbon dioxide (CO2), methane (CH3), nitrous oxide (N2O), and fluorinated gases. Some of these gases occur naturally and some are created by human activities which can increase their concentrations. The most comm...

  8. Greenhouse

    Data.gov (United States)

    Federal Laboratory Consortium — PurposeThe greenhouse at ERDC’s Cold Regions Research and Engineering Laboratory (CRREL) is used for germination and root-growth studies to support basic and field...

  9. 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].

  10. 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...

  11. 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.

  12. 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.

  13. Modelling of turbulent combustion in the blast furnace raceway

    Energy Technology Data Exchange (ETDEWEB)

    Karvinen, R; Maekiranta, R [Tampere Univ. (Finland). Energy and Process Engineering

    1997-12-31

    The phenomena concerning coke-gas -suspension and simultaneous combustion of solid coke particles and residual fuel oil in a blast furnace raceway are modelled. The flow field of suspension is predicted by using the two fluid model, which is based on the Eulerian method, in the Phoenics code. The standard k-e -model of turbulence is used. Pyrolysis of oil droplets is calculated with the own coded subroutine, which is based on the Lagrangian approach. Gas phase reaction rate is assumed to be controlled by chemical kinetics. Radiative heat transfer is calculated by using the six-flux method. Heterogenous surface reactions are used for the coke particles. Calculations without coke combustion show that due to a poor mixing in the hot blast, pyrolysis gases of residual fuel oil have not time enough to react with oxygen. It is obvious that if combustion of coke particles is taken into account, the oxygen content in the blast decreases to such a level, that unburnt pyrolysis gases can flow out of the raceway causing problems. The distribution of coke void fraction has been succeeded to predict in the raceway domain. Coke particles fall from the upper part of the raceway to the hot blast forming locally high concentrations, which affect very strongly the oxygen distribution of the hot blast. (orig.) SULA 2 Research Programme; 10 refs.

  14. Modelling of turbulent combustion in the blast furnace raceway

    Energy Technology Data Exchange (ETDEWEB)

    Karvinen, R.; Maekiranta, R. [Tampere Univ. (Finland). Energy and Process Engineering

    1996-12-31

    The phenomena concerning coke-gas -suspension and simultaneous combustion of solid coke particles and residual fuel oil in a blast furnace raceway are modelled. The flow field of suspension is predicted by using the two fluid model, which is based on the Eulerian method, in the Phoenics code. The standard k-e -model of turbulence is used. Pyrolysis of oil droplets is calculated with the own coded subroutine, which is based on the Lagrangian approach. Gas phase reaction rate is assumed to be controlled by chemical kinetics. Radiative heat transfer is calculated by using the six-flux method. Heterogenous surface reactions are used for the coke particles. Calculations without coke combustion show that due to a poor mixing in the hot blast, pyrolysis gases of residual fuel oil have not time enough to react with oxygen. It is obvious that if combustion of coke particles is taken into account, the oxygen content in the blast decreases to such a level, that unburnt pyrolysis gases can flow out of the raceway causing problems. The distribution of coke void fraction has been succeeded to predict in the raceway domain. Coke particles fall from the upper part of the raceway to the hot blast forming locally high concentrations, which affect very strongly the oxygen distribution of the hot blast. (orig.) SULA 2 Research Programme; 10 refs.

  15. Promoting helix pitch and trichome length to improve biomass harvesting efficiency and carbon dioxide fixation rate by Spirulina sp. in 660 m2 raceway ponds under purified carbon dioxide from a coal chemical flue gas.

    Science.gov (United States)

    Cheng, Jun; Guo, Wangbiao; Ameer Ali, Kubar; Ye, Qing; Jin, Guiyong; Qiao, Zhanshan

    2018-08-01

    The helix pitch and trichome length of Spirulina sp. were promoted to improve the biomass harvesting efficiency and CO 2 fixation rate in 660 m 2 raceway ponds aerated with food-grade CO 2 purified from a coal chemical flue gas. The CO 2 fixation rate was improved with increased trichome length of the Spirulina sp. in a raceway pond with double paddlewheels, baffles, and CO 2 aerators (DBA raceway pond). The trichome length has increased by 33.3 μm, and CO 2 fixation rate has increased by 42.3% and peaked to 51.3 g/m 2 /d in a DBA raceway pond. Biomass harvesting efficiency was increased with increased helix pitch. When the day-average greenhouse temperature was 33 °C and day-average sunlight intensity was 72,100 lu×, the helix pitch of Spirulina sp. was increased to 56.2 μm. Hence the biomass harvesting efficiency was maximized to 75.6% and biomass actual yield was increased to 35.9 kg in a DBA raceway pond. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. 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.

  17. 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.

  18. Energy Productivity of the High Velocity Algae Raceway Integrated Design (ARID-HV)

    Energy Technology Data Exchange (ETDEWEB)

    Attalah, Said; Waller, Peter M.; Khawam, George; Ryan, Randy D.; Huesemann, Michael H.

    2015-06-03

    The original Algae Raceway Integrated Design (ARID) raceway was an effective method to increase algae culture temperature in open raceways. However, the energy input was high and flow mixing was poor. Thus, the High Velocity Algae Raceway Integrated Design (ARID-HV) raceway was developed to reduce energy input requirements and improve flow mixing in a serpentine flow path. A prototype ARID-HV system was installed in Tucson, Arizona. Based on algae growth simulation and hydraulic analysis, an optimal ARID-HV raceway was designed, and the electrical energy input requirement (kWh ha-1 d-1) was calculated. An algae growth model was used to compare the productivity of ARIDHV and conventional raceways. The model uses a pond surface energy balance to calculate water temperature as a function of environmental parameters. Algae growth and biomass loss are calculated based on rate constants during day and night, respectively. A 10 year simulation of DOE strain 1412 (Chlorella sorokiniana) showed that the ARID-HV raceway had significantly higher production than a conventional raceway for all months of the year in Tucson, Arizona. It should be noted that this difference is species and climate specific and is not observed in other climates and with other algae species. The algae growth model results and electrical energy input evaluation were used to compare the energy productivity (algae production rate/energy input) of the ARID-HV and conventional raceways for Chlorella sorokiniana in Tucson, Arizona. The energy productivity of the ARID-HV raceway was significantly greater than the energy productivity of a conventional raceway for all months of the year.

  19. Experimental and modelling of Arthrospira platensis cultivation in open raceway ponds.

    Science.gov (United States)

    Ranganathan, Panneerselvam; Amal, J C; Savithri, S; Haridas, Ajith

    2017-10-01

    In this study, the growth of Arthrospira platensis was studied in an open raceway pond. Furthermore, dynamic model for algae growth and CFD modelling of hydrodynamics in open raceway pond were developed. The dynamic behaviour of the algal system was developed by solving mass balance equations of various components, considering light intensity and gas-liquid mass transfer. A CFD modelling of the hydrodynamics of open raceway pond was developed by solving mass and momentum balance equations of the liquid medium. The prediction of algae concentration from the dynamic model was compared with the experimental data. The hydrodynamic behaviour of the open raceway pond was compared with the literature data for model validation. The model predictions match the experimental findings. Furthermore, the hydrodynamic behaviour and residence time distribution in our small raceway pond were predicted. These models can serve as a tool to assess the pond performance criteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Seismic design criteria used for electrical raceway systems in commercial nuclear power plants

    International Nuclear Information System (INIS)

    Summers, P.B.; Manrique, M.A.; Nelson, T.A.

    1991-01-01

    This paper summarizes some of the seismic design approaches, relevant technical issues and criteria used over the years for design of electrical raceway systems at commercial nuclear power plant facilities. The approaches used for design and endorsed by the NRC can be seen to be quite varied. In recent years, considerably more rigor has been required for raceway design, as well as for the level of design basis documentation produced. However, there has also been a willingness by the NRC to accept rational approaches based on testing, analytical results or experience data, provided proper justification is given. Such rational approaches can simplify the significant task of analysis, design and construction of miles of raceways and thousands of raceway supports. Summarizing past practice and identifying relevant technical issues are an important first step in formalizing up-to-date criteria for new raceway designs

  1. Seawater State Variables in Hatchery and Raceway Tanks

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ambient seawater temperature and salinity was recorded on an intermittent basis for comparison with adjusted temperatures used in the aquaculture of bivalves

  2. 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

  3. 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...

  4. Two-Phase Flow Modeling of Solid Dissolution in Liquid for Nutrient Mixing Improvement in Algal Raceway Ponds

    Directory of Open Access Journals (Sweden)

    Haider Ali

    2018-04-01

    Full Text Available Achieving optimal nutrient concentrations is essential to increasing the biomass productivity of algal raceway ponds. Nutrient mixing or distribution in raceway ponds is significantly affected by hydrodynamic and geometric properties. The nutrient mixing in algal raceway ponds under the influence of hydrodynamic and geometric properties of ponds is yet to be explored. Such a study is required to ensure optimal nutrient concentrations in algal raceway ponds. A novel computational fluid dynamics (CFD model based on the Euler–Euler numerical scheme was developed to investigate nutrient mixing in raceway ponds under the effects of hydrodynamic and geometric properties. Nutrient mixing was investigated by estimating the dissolution of nutrients in raceway pond water. Experimental and CFD results were compared and verified using solid–liquid mass transfer coefficient and nutrient concentrations. Solid–liquid mass transfer coefficient, solid holdup, and nutrient concentrations in algal pond were estimated with the effects of pond aspect ratios, water depths, paddle wheel speeds, and particle sizes of nutrients. From the results, it was found that the proposed CFD model effectively simulated nutrient mixing in raceway ponds. Nutrient mixing increased in narrow and shallow raceway ponds due to effective solid–liquid mass transfer. High paddle wheel speeds increased the dissolution rate of nutrients in raceway ponds.

  5. Fluid-dynamic characterization of real-scale raceway reactors for microalgae production

    International Nuclear Information System (INIS)

    Mendoza, J.L.; Granados, M.R.; Godos, I. de; Acién, F.G.; Molina, E.; Banks, C.; Heaven, S.

    2013-01-01

    The fluid dynamic characterization of a 100 m length × 1 m wide channel raceway photobioreactor was carried out. The effects of water depth, liquid velocity and the presence, or absence, of sump baffles to improve the CO 2 supply transfer were considered in relation to on the power consumption, residence time and mixing in the reactor was studied. When operated at a depth of 20 cm, the power consumption was between 1.5 and 8.4 W m −3 depending on the forward velocity, with higher values occurring when the baffle was in place. Residence times and the degree of mixing at each section of the raceway (paddlewheel, bends, channels and sump) were measured experimentally. Mixing occurred mainly in the sump, paddlewheel and bends, with a maximum dispersion coefficient of 0.07 m 2 s −1 . These sections, however, only contributed a small fraction to the total volume of the raceway. Bodenstein numbers from 200 to 540 for the channel sections indicated plug-flow characteristics. Mixing times ranged from 1.4 to 6 h, with the presence of the baffle greatly increasing these times despite higher specific power consumption. A total of 15–20 circuits of the raceway were needed to achieve complete mixing without the baffle, compared to 30–40 cycles with the baffle. Vertical mixing was very poor whereas axial mixing was similar to that achieved in closed photobioreactors. The methodologies applied were shown to be useful in determining the fluid dynamics of a raceway photobioreactor. Equations useful in simulating the power consumption as a function of the design and operation parameters have been validated. -- Highlights: •Power consumption due to accessories can limit the use of raceway reactors for energy purposes. •Use of baffle to enhance mass transfer dramatically increases the power consumption in this type of photobioreactors. •High mixing time, in the order of hours, in raceway reactors limits the operation mode of these systems

  6. 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.

  7. Evaluation of Pacific white shrimp (Litopenaeus vannamei health during a superintensive aquaculture growout using NMR-based metabolomics.

    Directory of Open Access Journals (Sweden)

    Tracey B Schock

    Full Text Available Success of the shrimp aquaculture industry requires technological advances that increase production and environmental sustainability. Indoor, superintensive, aquaculture systems are being developed that permit year-round production of farmed shrimp at high densities. These systems are intended to overcome problems of disease susceptibility and of water quality issues from waste products, by operating as essentially closed systems that promote beneficial microbial communities (biofloc. The resulting biofloc can assimilate and detoxify wastes, may provide nutrition for the farmed organisms resulting in improved growth, and may aid in reducing disease initiated from external sources. Nuclear magnetic resonance (NMR-based metabolomic techniques were used to assess shrimp health during a full growout cycle from the nursery phase through harvest in a minimal-exchange, superintensive, biofloc system. Aberrant shrimp metabolomes were detected from a spike in total ammonia nitrogen in the nursery, from a reduced feeding period that was a consequence of surface scum build-up in the raceway, and from the stocking transition from the nursery to the growout raceway. The biochemical changes in the shrimp that were induced by the stressors were essential for survival and included nitrogen detoxification and energy conservation mechanisms. Inosine and trehalose may be general biomarkers of stress in Litopenaeus vannamei. This study demonstrates one aspect of the practicality of using NMR-based metabolomics to enhance the aquaculture industry by providing physiological insight into common environmental stresses that may limit growth or better explain reduced survival and production.

  8. Evaluation of Pacific White Shrimp (Litopenaeus vannamei) Health during a Superintensive Aquaculture Growout Using NMR-Based Metabolomics

    Science.gov (United States)

    Schock, Tracey B.; Duke, Jessica; Goodson, Abby; Weldon, Daryl; Brunson, Jeff; Leffler, John W.; Bearden, Daniel W.

    2013-01-01

    Success of the shrimp aquaculture industry requires technological advances that increase production and environmental sustainability. Indoor, superintensive, aquaculture systems are being developed that permit year-round production of farmed shrimp at high densities. These systems are intended to overcome problems of disease susceptibility and of water quality issues from waste products, by operating as essentially closed systems that promote beneficial microbial communities (biofloc). The resulting biofloc can assimilate and detoxify wastes, may provide nutrition for the farmed organisms resulting in improved growth, and may aid in reducing disease initiated from external sources. Nuclear magnetic resonance (NMR)-based metabolomic techniques were used to assess shrimp health during a full growout cycle from the nursery phase through harvest in a minimal-exchange, superintensive, biofloc system. Aberrant shrimp metabolomes were detected from a spike in total ammonia nitrogen in the nursery, from a reduced feeding period that was a consequence of surface scum build-up in the raceway, and from the stocking transition from the nursery to the growout raceway. The biochemical changes in the shrimp that were induced by the stressors were essential for survival and included nitrogen detoxification and energy conservation mechanisms. Inosine and trehalose may be general biomarkers of stress in Litopenaeus vannamei. This study demonstrates one aspect of the practicality of using NMR-based metabolomics to enhance the aquaculture industry by providing physiological insight into common environmental stresses that may limit growth or better explain reduced survival and production. PMID:23555690

  9. 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.

  10. Effects of rearing density and raceway conformation on growth, food conversion, and survival of juvenile spring chinook salmon

    Science.gov (United States)

    Ewing, R.D.; Sheahan, J.E.; Lewis, M.A.; Palmisano, Aldo N.

    2000-01-01

    Four brood years of juvenile spring chinook salmon Oncorhynchus tshawytscha were reared in conventional and baffled raceways at various rearing densities and loads at Willamette Hatchery, Oregon. A period of rapid linear growth occurred from August to November, but there was little or no growth from November to March when the fish were released. Both fall and winter growth rates were inversely related to rearing density. Final weight and length were also inversely related to rearing density. No significant relationship between load and any growth variable was observed. Fish reared at lower densities in conventional raceways tended to develop bimodal length distributions in winter and early spring. Fish reared in conventional raceways showed significantly larger growth rates and final lengths and weights than those reared in baffled raceways. Food conversions and average delivery times for feed were significantly greater in baffled than in conventional raceways. No significant relationships were observed between either rearing density or load and condition factor, food conversion, or mortality. Mortality was not significantly different between the two raceway types. When fish were transported to seawater for further rearing, there were no significant relationships between mortality in seawater and rearing density or load, but fish reared in baffled raceways had significantly higher mortality than those reared in conventional raceways.

  11. 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...

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

    Directory of Open Access Journals (Sweden)

    S. Sumoharjo

    2013-06-01

    Full Text Available Integrated multi-trophic aquaculture pays more attention as a bio-integrated food production system that serves as a model of sustainable aquaculture, minimizes waste discharge, increases diversity and yields multiple products. The objectives of this research were to analyze the efficiency of total ammonia nitrogen biofiltration and its effect on carrying capacity of fish rearing units. Pilot-scale bioreactor was designed with eight run-raceways (two meters of each that assembled in series. Race 1-3 were used to stock silky worm (Tubifex sp as detrivorous converter, then race 4-8 were used to plant three species of leaf-vegetable as photoautotrophic converters, i.e; spinach (Ipomoea reptana, green mustard (Brassica juncea and basil (Ocimum basilicum. The three plants were placed in randomized block design based on water flow direction. Mass balance of nutrient analysis, was applied to figure out the efficiency of bio-filtration and its effect on carrying capacity of rearing units. The result of the experiment showed that 86.5 % of total ammonia nitrogen removal was achieved in 32 days of culturing period. This efficiency able to support the carrying capacity of the fish tank up to 25.95 kg/lpm with maximum density was 62.69 kg/m3 of fish biomass productionDoi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85 [How to cite this article: Sumoharjo, S.  and Maidie, A. (2013. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture.  International Journal of  Science and Engineering, 4(2,80-85. Doi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85

  13. 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…

  14. 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...

  15. 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.

  16. 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....

  17. 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,…

  18. Investigation on novel raceway pond with inclined paddle wheels through simulation and microalgae culture experiments.

    Science.gov (United States)

    Zeng, Fanxue; Huang, Jianke; Meng, Chen; Zhu, Fachao; Chen, Jianpei; Li, Yuanguang

    2016-01-01

    The open raceway ponds are nowadays the most used large-scale reactors for microalgae culture. To avoid the stacking of microalgae, the paddle wheels are the most widely used to circulate and mix the culture medium. In this paper, a numerical simulation using computational fluid dynamics (CFD) was used to investigate the hydrodynamic characteristics of open raceway ponds with different types of paddle wheels (the traditional paddle wheels and the novel paddle wheels with specially inclined angle of the blades). The particle image velocimetry (PIV) was used to validate the reliability of the CFD model. The CFD simulation results showed that the novel raceway pond with 15° inclined angle of the blades had the best mixing efficiency under the same power consumption. Lastly, the results of microalgae culture experiments showed that the growth rates of Chlorella pyrenoidosa in the novel raceway pond with 15° inclined angle of the blades were higher than those in the traditional reactor. The results of the culture experiments and CFD simulations were identical with each other. Therefore, a novel paddle wheel with 15° inclined angle of the blades was obtained for better microalgae cultivation.

  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. 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 ...

  1. Greenhouse Gases

    Science.gov (United States)

    ... Production of Hydrogen Use of Hydrogen Greenhouse Gases Basics | | Did you know? Without naturally occurring greenhouse gases, the earth would be too cold to support life as we know it. Without the greenhouse effect, ...

  2. 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)

  3. 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…

  4. 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

  5. Extracorporeal tubing in the roller pump raceway: physical changes and particulate generation.

    Science.gov (United States)

    Spiwak, Allison J Bednarski; Horbal, Alexander; Leatherbury, Robert; Hansford, Derek J

    2008-09-01

    Plasticized polyvinyl chloride tubing is used as the blood conduit in the heart lung bypass circuit. The section in the roller pump undergoes rigorous compression. Fatigue leads to material changes in weight and length of the bulk material. Particles are released during normal pump operation. This study evaluates the time course of particle loss. Three segments of 1/2" ID tubing run in the raceway for 30-minute, 1-hour, or 2-hour. The fluid path of each segment includes an oxygenator; a castor oil blend was used for the prime. The 5 mL sample was acquired at 10 minute intervals. Raceway tubing segments were measured for a change in weight and length. The same procedure repeated with 1/4" ID and 3/8" ID tubing. All tubing increased at least 5 mm by the 2-hour trial. There were no remarkable changes in weight. Particles were measured for size and percent volume. Tubing with 1/2" ID performed most consistently for particle release during all trials. Particles were observed as small as 1 nm. Particles as large as 3 micron could be confirmed. For all tubing there was particle release by 30 minutes. Perfusionists must consider tubing inner diameter and wall thickness in choosing the pPVC for the raceway in order to minimize particulate emboli. This research suggests that 3/8" ID tubing produces spalls inconsistently compared to 2" ID tubing. Thinner wall thickness tubing also has the potential to limit spall formation.

  6. Comparison of Microalgae Cultivation in Photobioreactor, Open Raceway Pond, and a Two-Stage Hybrid System

    Energy Technology Data Exchange (ETDEWEB)

    Narala, Rakesh R.; Garg, Sourabh; Sharma, Kalpesh K.; Thomas-Hall, Skye R.; Deme, Miklos; Li, Yan; Schenk, Peer M., E-mail: p.schenk@uq.edu.au [Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, QLD (Australia)

    2016-08-02

    In the wake of intensive fossil fuel usage and CO{sub 2} accumulation in the environment, research is targeted toward sustainable alternate bioenergy that can suffice the growing need for fuel and also that leaves a minimal carbon footprint. Oil production from microalgae can potentially be carried out more efficiently, leaving a smaller footprint and without competing for arable land or biodiverse landscapes. However, current algae cultivation systems and lipid induction processes must be significantly improved and are threatened by contamination with other algae or algal grazers. To address this issue, we have developed an efficient two-stage cultivation system using the marine microalga Tetraselmis sp. M8. This hybrid system combines exponential biomass production in positive pressure air lift-driven bioreactors with a separate synchronized high-lipid induction phase in nutrient deplete open raceway ponds. A comparison to either bioreactor or open raceway pond cultivation system suggests that this process potentially leads to significantly higher productivity of algal lipids. Nutrients are only added to the closed bioreactors, while open raceway ponds have turnovers of only a few days, thus reducing the issue of microalgal grazers.

  7. Comparison of microalgae cultivation in photobioreactor, open raceway pond, and a two-stage hybrid system

    Directory of Open Access Journals (Sweden)

    Rakesh R Narala

    2016-08-01

    Full Text Available In the wake of intensive fossil fuel usage and CO2 accumulation in the environment, research is targeted towards sustainable alternate bioenergy that can suffice the growing need for fuel and also that leaves a minimal carbon footprint. Oil production from microalgae can potentially be carried out more efficiently, leaving a smaller footprint and without competing for arable land or biodiverse landscapes. However, current algae cultivation systems and lipid induction processes must be significantly improved and are threatened by contamination with other algae or algal grazers. To address this issue, we have developed an efficient two-stage cultivation system using the marine microalga Tetraselmis sp. M8. This hybrid system combines exponential biomass production in positive pressure air lift-driven bioreactors with a separate synchronized high-lipid induction phase in nutrient deplete open raceway ponds. A comparison to either bioreactor or open raceway pond cultivation system suggests that this process potentially leads to significantly higher productivity of algal lipids. Nutrients are only added to the closed bioreactors while open raceway ponds have turnovers of only a few days, thus reducing the issue of microalgal grazers.

  8. Comparison of Microalgae Cultivation in Photobioreactor, Open Raceway Pond, and a Two-Stage Hybrid System

    International Nuclear Information System (INIS)

    Narala, Rakesh R.; Garg, Sourabh; Sharma, Kalpesh K.; Thomas-Hall, Skye R.; Deme, Miklos; Li, Yan; Schenk, Peer M.

    2016-01-01

    In the wake of intensive fossil fuel usage and CO 2 accumulation in the environment, research is targeted toward sustainable alternate bioenergy that can suffice the growing need for fuel and also that leaves a minimal carbon footprint. Oil production from microalgae can potentially be carried out more efficiently, leaving a smaller footprint and without competing for arable land or biodiverse landscapes. However, current algae cultivation systems and lipid induction processes must be significantly improved and are threatened by contamination with other algae or algal grazers. To address this issue, we have developed an efficient two-stage cultivation system using the marine microalga Tetraselmis sp. M8. This hybrid system combines exponential biomass production in positive pressure air lift-driven bioreactors with a separate synchronized high-lipid induction phase in nutrient deplete open raceway ponds. A comparison to either bioreactor or open raceway pond cultivation system suggests that this process potentially leads to significantly higher productivity of algal lipids. Nutrients are only added to the closed bioreactors, while open raceway ponds have turnovers of only a few days, thus reducing the issue of microalgal grazers.

  9. Feasibility analysis of the utilization of moderator heat for agricultural and aquacultural purposes, Bruce nuclear power development

    International Nuclear Information System (INIS)

    1977-12-01

    A study is presented of the feasibility of using moderator reject heat from the Bruce nuclear power development either to heat greenhouses or to aid in a warm water hatchery or aquaculture operation. The study examines heat extraction and delivery plans, reliability of supply, pricing schedules, the Ontario greenhouse industry, site selection criteria, water transmission and distribution, costs, approvals required, and a construction timetable. Total system analysis shows that a greenhouse facility would be viable but the aquaculture/hatchery scheme is more cost-effective. (E.C.B.)

  10. 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...

  11. 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...

  12. 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...

  13. 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.

  14. 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 ...

  15. Greener greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Paksoy, Halime; Turgut, Bekir; Beyhan, Beyza; Dasgan, H. Yildiz; Evliya, Hunay; Abak, Kazim; Bozdag, Saziye

    2010-09-15

    Agricultural greenhouses are solution to the increased demand for higher production yields, facilitating off season cultivation and allowing the growth of certain varieties in areas where it was not possible earlier. Heating and/or cooling system, required to maintain the inside micro-climate in greenhouses mostly rely on fossil fuels and/or electricity. This paper aims to discuss the 'greener' solutions for heating and cooling systems of greenhouses based on different thermal energy storage concepts. Results from a greenhouse Aquifer Thermal Energy Storage (ATES) application in Turkey producing tomatoes with zero fossil fuels and up to 40% higher yield are presented.

  16. 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…

  17. 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....

  18. Residential greenhouse

    Energy Technology Data Exchange (ETDEWEB)

    1985-02-01

    The following report examines the technical and economic viability of residential greenhouse additions in Whitehorse, Yukon. The greenhouse was constructed using the south facing wall of an existing residence as a common wall. Total construction costs were $18,000, including labour. Annual fuel demand for the residence has been reduced by about 10 per cent for an annual saving of $425. In addition, produce to the value of $1,000 is grown annually in the greenhouse for domestic consumption and commercial resale. Typically the greenhouse operates for nine months each year. There is a net thermal loss during the months of November, December and January as a result of the large area of glazing. As well as supplementing the heating supply solar greenhouses can provide additional cash crops which can be used to offset the cost of construction. Humidity problems are minimal and can be dealt with by exhausting high humidity air. One system which has been considered for the greenhouse is to use a standard residential heat pump to remove excess moisture and to pump heat into the house. This would have a secondary benefit of excluding the need to circulate greenhouse air through the house. Thus any allergenic reactions to the greenhouse air would be prevented. 8 refs., 3 figs, 2 tabs.

  19. 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.

  20. Integration of Tuyere, Raceway and Shaft Models for Predicting Blast Furnace Process

    Science.gov (United States)

    Fu, Dong; Tang, Guangwu; Zhao, Yongfu; D'Alessio, John; Zhou, Chenn Q.

    2018-06-01

    A novel modeling strategy is presented for simulating the blast furnace iron making process. Such physical and chemical phenomena are taking place across a wide range of length and time scales, and three models are developed to simulate different regions of the blast furnace, i.e., the tuyere model, the raceway model and the shaft model. This paper focuses on the integration of the three models to predict the entire blast furnace process. Mapping output and input between models and an iterative scheme are developed to establish communications between models. The effects of tuyere operation and burden distribution on blast furnace fuel efficiency are investigated numerically. The integration of different models provides a way to realistically simulate the blast furnace by improving the modeling resolution on local phenomena and minimizing the model assumptions.

  1. Greenhouse effect

    International Nuclear Information System (INIS)

    1992-01-01

    This special issue is devoted to the greenhouse effect and reviews the possible climate change by mankind, paleoclimates, climate models, measurement of terrestrial temperature, CO 2 concentration and energy policy

  2. 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.

  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. 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), ...

  5. 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.

  6. 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.

  7. 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.

  8. Greenhouse effect

    International Nuclear Information System (INIS)

    Lepetit, J.P.

    1992-01-01

    This book speaks about the growth of greenhouse gases content in the atmosphere and try to forecast the different scenarios which may happen. But, in spite of international cooperation and coordinated research programs, nobody owns the answer. So possible future climatic changes depend on the behavior of the concerned actors. A review of energy policy driven by USA, Japan, Sweden, United Kingdom and Federal Republic of Germany is given. Political management of this file and public opinion in front of greenhouse effect are also described. 7 refs., 3 figs., 6 tabs

  9. A cost analysis of microalgal biomass and biodiesel production in open raceways treating municipal wastewater and under optimum light wavelength.

    Science.gov (United States)

    Kang, Zion; Kim, Byung-Hyuk; Ramanan, Rishiram; Choi, Jong-Eun; Yang, Ji-Won; Oh, Hee-Mock; Kim, Hee-Sik

    2015-01-01

    Open raceway ponds are cost-efficient for mass cultivation of microalgae compared with photobioreactors. Although low-cost options like wastewater as nutrient source is studied to overcome the commercialization threshold for biodiesel production from microalgae, a cost analysis on the use of wastewater and other incremental increases in productivity has not been elucidated. We determined the effect of using wastewater and wavelength filters on microalgal productivity. Experimental results were then fitted into a model, and cost analysis was performed in comparison with control raceways. Three different microalgal strains, Chlorella vulgaris AG10032, Chlorella sp. JK2, and Scenedesmus sp. JK10, were tested for nutrient removal under different light wavelengths (blue, green, red, and white) using filters in batch cultivation. Blue wavelength showed an average of 27% higher nutrient removal and at least 42% higher chemical oxygen demand removal compared with white light. Naturally, the specific growth rate of microalgae cultivated under blue wavelength was on average 10.8% higher than white wavelength. Similarly, lipid productivity was highest in blue wavelength, at least 46.8% higher than white wavelength, whereas FAME composition revealed a mild increase in oleic and palmitic acid levels. Cost analysis reveals that raceways treating wastewater and using monochromatic wavelength would decrease costs from 2.71 to 0.73 $/kg biomass. We prove that increasing both biomass and lipid productivity is possible through cost-effective approaches, thereby accelerating the commercialization of low-value products from microalgae, like biodiesel.

  10. Pilot Greenhouse

    CERN Multimedia

    1983-01-01

    This pilot greenhouse was built in collaboration with the "Association des Maraichers" of Geneva in the frame of the study for making use of the heat rejected as warm water by CERN accelerators and experiments. Among other improvements, more automated and precise regulation systems for heating and ventilation were developed. See also 8305598X.

  11. 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

  12. 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.

  13. 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

  14. 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…

  15. 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.

  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. 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...

  18. 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.

  19. INNOVATION IN THE AQUACULTURE SECTOR

    Directory of Open Access Journals (Sweden)

    María Candelaria Beltrán Meza

    2017-07-01

    Full Text Available Currently the globalized business environment prompts companiesto develop strategies to stay within international competition, which has generated in organizations the need to offer new products and services that boost their competitiveness. In this context, innovation is a process that requires vision and creative ideas, guided by a leader and developed by an interdisciplinary team, become an added value for consumers. Nowadays, it is common to collaborate with competitors to share risks, complementing one's strengths with the other's weaknesses, in a new way of doing business, this strategic alliance can be strengthened by linking research centers integrated in the business innovation projects. The purpose of the study is to describe the innovation agenda that an aquaculture company plans to carry out in the short, medium and long term, in order to maintain its competitiveness in the international market.

  20. DNA vaccines for aquacultured fish

    DEFF Research Database (Denmark)

    Lorenzen, Niels; LaPatra, S.E.

    2005-01-01

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

  1. Biogeochemical ecology of aquaculture ponds

    International Nuclear Information System (INIS)

    Weisburd, R.S.J.

    1988-01-01

    Two methods to determine rates of organic matter production and consumption were applied in shrimp aquaculture ponds. Several questions were posed: can net rates of organic matter production and consumption be determined accurately through application of dissolved inorganic carbon (DIC) mass balance in a pond with high advective through-put? Are organically loaded aquaculture ponds autotrophic? How do rates of organic production vary temporally? Are there diurnal changes in respiration rates? Four marine ponds in Hawaii have been evaluated for a 53 day period through the use of geochemical mass balances. All fluxes of DIC into and out of the ponds were considered. DIC was calculated from hourly pH measurements and weekly alkalinity measurements. Average uptake of DIC from the pond water, equivalent to net community production, revealed net autotrophy in all cases. Hourly and longer period variations in organic matter production rates were examined. The daily cycle dominated the variation in rates of net community production. Maximal rates of net community production were maintained for four to six hours starting in mid-morning. Respiration rates decreased rapidly during the night in two of the ponds and remained essentially constant in the others. A similar pattern of decreasing respiration at night was seen in freshwater shrimp ponds which were studied with incubations. A new method involving isotope dilution of 14 C-labeled DIC was used to measure respiration rates in light and dark bottles. This method is an inexpensive and convenient procedure which should also be useful in other environments. The incubations demonstrated that plankton respiration rates peak at or soon after solar noon and vary over the course of the day by about a factor of two

  2. Aquaculture: global status and trends

    Science.gov (United States)

    Bostock, John; McAndrew, Brendan; Richards, Randolph; Jauncey, Kim; Telfer, Trevor; Lorenzen, Kai; Little, David; Ross, Lindsay; Handisyde, Neil; Gatward, Iain; Corner, Richard

    2010-01-01

    Aquaculture contributed 43 per cent of aquatic animal food for human consumption in 2007 (e.g. fish, crustaceans and molluscs, but excluding mammals, reptiles and aquatic plants) and is expected to grow further to meet the future demand. It is very diverse and, contrary to many perceptions, dominated by shellfish and herbivorous and omnivorous pond fish either entirely or partly utilizing natural productivity. The rapid growth in the production of carnivorous species such as salmon, shrimp and catfish has been driven by globalizing trade and favourable economics of larger scale intensive farming. Most aquaculture systems rely on low/uncosted environmental goods and services, so a critical issue for the future is whether these are brought into company accounts and the consequent effects this would have on production economics. Failing that, increased competition for natural resources will force governments to allocate strategically or leave the market to determine their use depending on activities that can extract the highest value. Further uncertainties include the impact of climate change, future fisheries supplies (for competition and feed supply), practical limits in terms of scale and in the economics of integration and the development and acceptability of new bio-engineering technologies. In the medium term, increased output is likely to require expansion in new environments, further intensification and efficiency gains for more sustainable and cost-effective production. The trend towards enhanced intensive systems with key monocultures remains strong and, at least for the foreseeable future, will be a significant contributor to future supplies. Dependence on external feeds (including fish), water and energy are key issues. Some new species will enter production and policies that support the reduction of resource footprints and improve integration could lead to new developments as well as reversing decline in some more traditional systems. PMID:20713392

  3. Aquaculture: global status and trends.

    Science.gov (United States)

    Bostock, John; McAndrew, Brendan; Richards, Randolph; Jauncey, Kim; Telfer, Trevor; Lorenzen, Kai; Little, David; Ross, Lindsay; Handisyde, Neil; Gatward, Iain; Corner, Richard

    2010-09-27

    Aquaculture contributed 43 per cent of aquatic animal food for human consumption in 2007 (e.g. fish, crustaceans and molluscs, but excluding mammals, reptiles and aquatic plants) and is expected to grow further to meet the future demand. It is very diverse and, contrary to many perceptions, dominated by shellfish and herbivorous and omnivorous pond fish either entirely or partly utilizing natural productivity. The rapid growth in the production of carnivorous species such as salmon, shrimp and catfish has been driven by globalizing trade and favourable economics of larger scale intensive farming. Most aquaculture systems rely on low/uncosted environmental goods and services, so a critical issue for the future is whether these are brought into company accounts and the consequent effects this would have on production economics. Failing that, increased competition for natural resources will force governments to allocate strategically or leave the market to determine their use depending on activities that can extract the highest value. Further uncertainties include the impact of climate change, future fisheries supplies (for competition and feed supply), practical limits in terms of scale and in the economics of integration and the development and acceptability of new bio-engineering technologies. In the medium term, increased output is likely to require expansion in new environments, further intensification and efficiency gains for more sustainable and cost-effective production. The trend towards enhanced intensive systems with key monocultures remains strong and, at least for the foreseeable future, will be a significant contributor to future supplies. Dependence on external feeds (including fish), water and energy are key issues. Some new species will enter production and policies that support the reduction of resource footprints and improve integration could lead to new developments as well as reversing decline in some more traditional systems.

  4. Temporal Eukarya, Bacteria, and Archaea biodiversity during cultivation of an alkaliphilic algae, Chlorella vulgaris, in an outdoor raceway pond

    Directory of Open Access Journals (Sweden)

    Tisza Ann Szeremy Bell

    2016-01-01

    Full Text Available Algal biofuels and valuable co-products are being produced in both open and closed cultivation systems. Growing algae in open pond systems may be a more economical alternative, but this approach allows environmental microorganisms to colonize the pond and potentially infect or outcompete the algal crop. In this study, we monitored the microbial community of an outdoor, open raceway pond inoculated with a high lipid-producing alkaliphilic alga, Chlorella vulgaris BA050. The strain C. vulgaris BA050 was previously isolated from Soap Lake, Washington, a system characterized by a high pH (approximately 9.8. An outdoor raceway pond (200L was inoculated with C. vulgaris and monitored for ten days and then the culture was transferred to a 2,000L raceway pond and cultivated for an additional six days. Community DNA samples were collected over the 16-day period in conjunction with water chemistry analyses and cell counts. Universal primers for the SSU rRNA gene sequences for Eukarya, Bacteria, and Archaea were used for barcoded pyrosequence determination. The environmental parameters that most closely correlated with C. vulgaris abundance were pH and phosphate. Community analyses indicated that the pond system remained dominated by the Chlorella population (93% of eukaryotic sequences, but was also colonized by other microorganisms. Bacterial sequence diversity increased over time while archaeal sequence diversity declined over the same time period. Using SparCC co-occurrence network analysis, a positive correlation was observed between C. vulgaris and Pseudomonas sp. throughout the experiment, which may suggest a symbiotic relationship between the two organisms. The putative relationship coupled with high pH may have contributed to the success of C. vulgaris. The characterization of the microbial community dynamics of an alkaliphilic open pond system provides significant insight into open pond systems that could be used to control photoautotrophic

  5. Analysis of bearing stiffness variations, contact forces and vibrations in radially loaded double row rolling element bearings with raceway defects

    Science.gov (United States)

    Petersen, Dick; Howard, Carl; Sawalhi, Nader; Moazen Ahmadi, Alireza; Singh, Sarabjeet

    2015-01-01

    A method is presented for calculating and analyzing the quasi-static load distribution and varying stiffness of a radially loaded double row bearing with a raceway defect of varying depth, length, and surface roughness. The method is applied to ball bearings on gearbox and fan test rigs seeded with line or extended outer raceway defects. When balls pass through the defect and lose all or part of their load carrying capacity, the load is redistributed between the loaded balls. This includes balls positioned outside the defect such that good raceway sections are subjected to increased loading when a defect is present. The defective bearing stiffness varies periodically at the ball spacing, and only differs from the good bearing case when balls are positioned in the defect. In this instance, the stiffness decreases in the loaded direction and increases in the unloaded direction. For an extended spall, which always has one or more balls positioned in the defect, this results in an average stiffness over the ball spacing period that is lower in the loaded direction in comparison to both the line spall and good bearing cases. The variation in bearing stiffness due to the defect produces parametric excitations of the bearing assembly. The qualitative character of the vibration response correlates to the character of the stiffness variations. Rapid stiffness changes at a defect exit produce impulses. Slower stiffness variations due to large wavelength waviness features in an extended spall produce low frequency excitation which results in defect components in the velocity spectra. The contact forces fluctuate around the quasi-static loads on the balls, with rapid stiffness changes producing high magnitude impulsive force fluctuations. Furthermore, it is shown that analyzing the properties of the dynamic model linearized at the quasi-static solutions provides greater insight into the time-frequency characteristics of the vibration response. This is demonstrated by relating

  6. 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

  7. 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...

  8. 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 ...

  9. 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...

  10. 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.

  11. 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; ...

  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. Dynamic Modeling of the Microalgae Cultivation Phase for Energy Production in Open Raceway Ponds and Flat Panel Photobioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Marsullo, Matteo [Department of Industrial Engineering, University of Padova, Padova (Italy); Mian, Alberto [Industrial Process and Energy System Engineering Group (IPESE), École Polytechnique Fédérale de Lausanne, Lausanne (Switzerland); Ensinas, Adriano Viana [Industrial Process and Energy System Engineering Group (IPESE), École Polytechnique Fédérale de Lausanne, Lausanne (Switzerland); Universidade Federal do ABC, Santo Andre (Brazil); Manente, Giovanni; Lazzaretto, Andrea, E-mail: andrea.lazzaretto@unipd.it [Department of Industrial Engineering, University of Padova, Padova (Italy); Marechal, François [Industrial Process and Energy System Engineering Group (IPESE), École Polytechnique Fédérale de Lausanne, Lausanne (Switzerland)

    2015-09-15

    A dynamic model of microalgae cultivation phase is presented in this work. Two cultivation technologies are taken into account: the open raceway pond and the flat panel photobioreactor. For each technology, the model is able to evaluate the microalgae areal and volumetric productivity and the energy production and consumption. Differently from the most common existing models in literature, which deal with a specific part of the overall cultivation process, the model presented here includes all physical and chemical quantities that mostly affect microalgae growth: the equation of the specific growth rate for the microalgae is influenced by CO{sub 2} and nutrients concentration in the water, light intensity, temperature of the water in the reactor, and by the microalgae species being considered. All these input parameters can be tuned to obtain reliable predictions. A comparison with experimental data taken from the literature shows that the predictions are consistent and slightly overestimating the productivity in the case of closed photobioreactor. The results obtained by the simulation runs are consistent with those found in literature, being the areal productivity for the open raceway pond between 50 and 70 t/(ha × year) in Southern Spain (Sevilla) and Brazil (Petrolina) and between 250 and 350 t/(ha × year) for the flat panel photobioreactor in the same locations.

  14. Dynamic modeling of the microalgae cultivation phase for energy production in open raceway ponds and flat panel photobioreactors

    Directory of Open Access Journals (Sweden)

    Matteo eMarsullo

    2015-09-01

    Full Text Available A dynamic model of microalgae cultivation phase is presented in this work. Two cultivation technologies are taken into account: the open raceway pond and the flat panel photobioreactor. For each technology, the model is able to evaluate the microalgae areal and volumetric productivity and the energy production and consumption. Differently from the most common existing models in literature, which deal with a specific part of the overall cultivation process, the model presented here includes all physical and chemical quantities that mostly affect microalgae growth: the equation of the specific growth rate for the microalgae is influenced by CO2 and nutrients concentration in the water, light intensity, temperature of the water in the reactor and by the microalgae species being considered. All these input parameters can be tuned to obtain reliable predictions. A comparison with experimental data taken from the literature shows that the predictions are consistent, slightly overestimating the productivity in case of closed photobioreactor. The results obtained by the simulation runs are consistent with those found in literature, being the areal productivity for the open raceway pond between 50 and 70 t/(ha*year in Southern Spain (Sevilla and Brazil (Petrolina and between 250 and 350 t/(ha*year for the flat panel photobioreactor in the same locations.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-04

    Aquaculture, the farming and husbandry of freshwater and marine organisms, is the newest and fastest growing US agricultural sector. In New Mexico, low winter temperatures and limited freshwater sources narrow culture production possibilities; however, it has long been recognized that the state has abundant supplies of both saline and geothermal ground waters. The purpose of this project was to demonstrate the achievable energy savings and value enhancement of the byproduct geothermal energy by cascading fluids for the production of commercial aquaculture species. Specifically the project involved evaluating the heating systems performance in terms of heating budget for the geothermal assist, determine the total quantity of water used for culture and heating, amount of geothermal byproduct heat extracted, and ability of the system to maintain culture water temperatures during critical heating periods of the year. In addition, an analysis was conducted to determine the compatibility of this new system with existing greenhouse heating requirements.

  16. COMPARISON OF POND AND RACEWAY PRODUCTION METHODS ON TEXTURE OF CHANNEL CATFISH (Ictalurus punctatus) FILLETS, SHOWING A DEPENDENCY ON SIZE AND FILLET POSITION

    Science.gov (United States)

    The objective of this study was to compare the effect of the production environment (pond vs in-pond raceway) on the chemical composition, color, and textural properties of channel catfish fillets. Compositional analysis consisted of percent moisture, lipid, protein, and ash content. Additional sa...

  17. Limiting Size of Fish Fillets at the Center of the Plate Improves the Sustainability of Aquaculture Production

    Directory of Open Access Journals (Sweden)

    Stephen F. Cross

    2011-07-01

    Full Text Available North American dining customers like to have a singular large piece of protein in the center of the plate. When fish is the protein of choice, the portion size from many species is limited by the overall size of the fish. Therefore, for these species, the means to achieve a singular larger portion of “center of the plate” protein is to grow a larger animal. However, fish become less efficient in converting feed to protein as they age. A second option would be to provide two smaller fillets originating from younger, more efficient fish. Here, the sustainability ramifications of these two protein provisioning strategies (single large or two small fillets are considered for three species of fish produced in aquaculture. Growth data for channel catfish (Ictalurus punctatus produced in ponds, rainbow trout (Oncorhynchus mykiss in raceways, and sablefish (Anoplopoma fimbria in marine net pens, were modeled to assess the total biomass and overall food conversion ratio for the production of small, medium or large fish. The production of small fish added an additional 50% or more biomass per year for trout, catfish, and sablefish compared to the production of large fish. Feed conversion ratios were also improved by nearly 10% for the smaller compared to larger fish of each species. Thus, even though all of these species tend to be considered aquaculture species of low environmental impact (and hence “green” or sustainable options, the product form requested by retailers and served by chefs can further increase the sustainability of these species.

  18. 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.

  19. 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...

  20. 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 ...

  1. 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.

  2. 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....

  3. 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, ...

  4. Gardening with Greenhouses

    Science.gov (United States)

    Keeler, Rusty

    2010-01-01

    Greenhouses come in all shapes, sizes, and price ranges: from simple hand-built plastic-covered frames to dazzling geodesic domes. Some child care centers install greenhouses as a part of their outdoor garden space. Other centers have incorporated a greenhouse into the building itself. Greenhouses provide a great opportunity for children to grow…

  5. 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.

  6. GREENHOUSE BRITAIN

    Directory of Open Access Journals (Sweden)

    David Haley

    2008-10-01

    Full Text Available We believe that the cultural landscape is largely formed by the dominant cultures of a place. “It is formed by a sometimes conflicted, sometimes consensual discourse or narrative from an array of stories, observations and intentions, first spoken by people of these dominant cultures and thereafter enacted on the ground. To our view, such a story has certain fluidity about it, and may change directions for any number of reasons. This work, Greenhouse Britain, is designed literally to express what the risingof waters would mean to the landscape of the island. It takes the 3 positions of defense, withdrawal and then defense, withdrawal to the high grounds. We suggest that the existing plans for greenhouse emissions control will be insufficient to keep temperature rise at 2° or less. In fact, we believe that the tipping point is past. In this context, the rising ocean becomes a form determinant. By “form determinant”, we mean, the rising ocean will determine many of the new forms that culture, industry and many other elements of civilization will have to take. There is another piece of this picture that we wish to give Voice to. That is up until this present rising of the world oceans, the creators of Western civilization have held and enacted the belief that all limitations in the physical world, particularly in the ecological world are there to be used and overcome. We think that the rising ocean is an opportunity for transformation, but it is exactly the reverse of a new frontier to overcome from civilization’s perspective. Now, from the ocean’s perspective, its boundary is perhaps a continuing, evolving transforming new frontier. Therefore, assuming a rapid rise of waters, even for a modest 5 meters in 100 years, there are apparently no models of precedence, no information, design, nor planning on the table, with the exception of ocean defenses and typical development models, albeit more energy efficient ones. It is the intention of

  7. Seasonal growth and mortality of juveniles of Lampsilis fasciola (Bivalvia: Unionidae) released to a fish hatchery raceway

    Science.gov (United States)

    Hanlon, Shane D.; Neves, Richard J.

    2006-01-01

    Recent efforts to restore remnant or extirpated populations of freshwater mussels have focused on artificial propagation as an effective and practical conservation strategy. Although artificially cultured juveniles have been produced and released to the wild at various times of the year, no study has investigated the best time of year to release these juveniles. Newly metamorphosed juveniles of the wavyrayed lampmussel (Lampsilis fasciola) were released into a stream-fed fish hatchery raceway during March, June, and September. Growth and survival rates were measured 32, 52, 72, and 92 days post-metamorphosis. Juveniles released in June experienced the greatest growth and survival rates. Juveniles released in September and March experienced high mortality within the first month of release and exhibited poor growth in the cool water conditions typical of those seasons. Overwinter survival exhibited a size-dependent relationship.

  8. 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...

  9. 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...

  10. 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 ...

  11. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    Science.gov (United States)

    Moffitt, Christine M.

    2016-01-01

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal efficiency, and measures of velocity using several tools. Computational fluid dynamics was used first to characterize hydraulics in the proposed retrofit that included removal of the traditional Burrows pond dividing wall and establishment of four counter rotating cells with appropriate drains and inlet water jets. Hydraulic residence time was subsequently established in the four full scale test tanks using measures of conductivity of a salt tracer introduced into the systems both with and without fish present. Vertical and horizontal velocities were also measured with acoustic Doppler velocimetry in transects across each of the rearing systems. Finally, we introduced ABS sinking beads that simulated fish solids then followed the kinetics of their removal via the drains to establish relative purge rates. The mixed cell raceway provided higher mean velocities and a more uniform velocity distribution than did the Burrows pond. Vectors revealed well-defined, counter-rotating cells in the mixed cell raceway, and were likely contributing factors in achieving a relatively high particle removal efficiency-88.6% versus 8.0% during the test period. We speculate retrofits of rearing ponds to mixed cell systems will improve both the rearing environments for the fish and solids removal, improving the efficiency and bio-security of fish culture. We recommend further testing in hatchery production trials to evaluate fish physiology and growth.

  12. 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.

  13. 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 ...

  14. 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

  15. 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.

  16. 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,…

  17. 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 ...

  18. 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.

  19. 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.

  20. 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...

  1. 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

  2. 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.

  3. 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.

  4. 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...

  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. 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 ...

  7. 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

  8. Measuring the potential for sustainable intensification of aquaculture in Bangladesh using life cycle assessment.

    Science.gov (United States)

    Henriksson, Patrik John Gustav; Belton, Ben; Jahan, Khondker Murshed-E-; Rico, Andreu

    2018-03-20

    Food production is a major driver of global environmental change and the overshoot of planetary sustainability boundaries. Greater affluence in developing nations and human population growth are also increasing demand for all foods, and for animal proteins in particular. Consequently, a growing body of literature calls for the sustainable intensification of food production, broadly defined as "producing more using less". Most assessments of the potential for sustainable intensification rely on only one or two indicators, meaning that ecological trade-offs among impact categories that occur as production intensifies may remain unaccounted for. The present study addresses this limitation using life cycle assessment (LCA) to quantify six local and global environmental consequences of intensifying aquaculture production in Bangladesh. Production data are from a unique survey of 2,678 farms, and results show multidirectional associations between the intensification of aquaculture production and its environmental impacts. Intensification (measured in material and economic output per unit primary area farmed) is positively correlated with acidification, eutrophication, and ecotoxicological impacts in aquatic ecosystems; negatively correlated with freshwater consumption; and indifferent with regard to global warming and land occupation. As production intensifies, the geographical locations of greenhouse gas (GHG) emissions, acidifying emissions, freshwater consumption, and land occupation shift from the immediate vicinity of the farm to more geographically dispersed telecoupled locations across the globe. Simple changes in fish farming technology and management practices that could help make the global transition to more intensive forms of aquaculture be more sustainable are identified. Copyright © 2018 the Author(s). Published by PNAS.

  9. Agriculture: Nurseries and Greenhouses

    Science.gov (United States)

    Nurseries and Greenhouses. Information about environmental requirements specifically relating to the production of many types of agricultural crops grown in nurseries and greenhouses, such as ornamental plants and specialty fruits and vegetables.

  10. Algae culture on drainwater from greenhouse horticulture. Towards an algae culture pilot for greenhouse horticulture; Algencultuur op drainwater uit de glastuinbouw. Naar een pilot algenteelt voor de glastuinbouw

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-09-15

    The agriculture sector is rapidly warming to the idea of algae culture. Arable farmers, livestock farmers and greenhouse growers are all interested. This report contains an elaborated plan for a pilot-scale practical test and three appendices. The two-year pilot is going to cost about EUR 1 million and will yield practical knowledge about using algae to purify drainwater from greenhouse horticulture. A partnership between numerous small algae growers in a sales cooperative should lead to a better market position. Appendix 1 gives a description of various algae systems and the different types of algae that can currently be cultivated. Chlorella and Arthrospira are the most suitable types for cultivation on greenhouse drainwater. The most economically viable choice appears to be a hybrid nursery with a photobioreactor for starter material and covered raceways for mass production. Appendix 2 gives specific options for combining greenhouse horticulture and algae culture, including the surface allocated to, respectively, algae culture and greenhouse horticulture. Appendix 3 gives the detailed findings of research conducted by Imares into algae on drainwater specifically for the oyster growing sector [Dutch] De belangstelling van het agrarisch bedrijfsleven voor de algenteelt groeit snel. Akkerbouwers, veehouders en glastuinders tonen interesse. Dit rapport bevat een uitwerking voor een praktijkproef op pilotschaal, en drie bijlagen. De praktijkproef van twee jaar gaat circa 1 miljoen euro kosten en levert kennis uit de praktijk op om afvalwater uit de glastuinbouw te zuiveren middels algen. Een samenwerkingsverband tussen tal van kleine algentelers in een afzetcoöperatie moet tot een betere marktpositie kunnen leiden. Bijlage 1 geeft een beschrijving van verschillende algensystemen en de verschillende types algen die op dit moment te kweken zijn. Chlorella en Arthrospira zijn de meest in aanmerking komende soorten om op drainwater uit de glastuinbouw te kweken. De

  11. The Dynamic Greenhouse Challenge

    Science.gov (United States)

    Roman, Harry T.

    2010-01-01

    Greenhouses are marvelous devices, allowing one to enjoy the flower spectacle of summer all year round. At night, greenhouses use supplemental heat to keep the fragile plants warm. Over the last 30 years, greenhouse technology has undergone many changes, with the structures being automated and monitored and low-cost plastic structures emerging as…

  12. 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.

  13. 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.

  14. Vertical Integration in the Taiwan Aquaculture Industry

    OpenAIRE

    Tzong-Ru Lee (Jiun-Shen); Yi-Hsu; Cheng-Jen Lin; Kongkiti Phusavat; Nirote Sinnarong

    2011-01-01

    The study aims to improve the distribution channels in the Taiwan aquaculture industry through a better vertical integration. This study is derived from a need to improve the distribution performance of agricultural-based industries in response to increasing food demands in Asia and elsewhere. Based on a four-by-eight matrix derived from both a value chain and a service profit chain, thirty different strategies are developed. This development is based on key success factors and strategies for...

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. Culture modes and financial evaluation of two oleaginous microalgae for biodiesel production in desert area with open raceway pond.

    Science.gov (United States)

    He, Qiaoning; Yang, Haijian; Hu, Chunxiang

    2016-10-01

    Cultivation modes of autotrophic microalgae for biodiesel production utilizing open raceway pond were analyzed in this study. Five before screened good microalgae were tested their lipid productivity and biodiesel quality again in outdoor 1000L ORP. Then, Chlorella sp. L1 and Monoraphidium dybowskii Y2 were selected due to their stronger environmental adaptability, higher lipid productivity and better biodiesel properties. Further scale up cultivation for two species with batch and semi-continuous culture was conducted. In 40,000L ORP, higher lipid productivity (5.15 versus 4.06gm(-2)d(-1) for Chlorella sp. L1, 5.35 versus 3.00gm(-2)d(-1) for M. dybowskii Y2) was achieved in semi-continuous mode. Moreover, the financial costs of 14.18$gal(-1) and 13.31$gal(-1) for crude biodiesel in two microalgae with semi-continuous mode were more economically feasible for commercial production on large scale outdoors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 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.

  1. 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...

  2. 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.

  3. 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...

  4. Chapter 14. Greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    Greenhouse heating is one of the most common uses of geothermal resources. Because of the significant heating requirements of greenhouses and their ability to use very low- temperature fluids, they are a natural application. The evaluation of a particular greenhouse project involves consideration of the structure heating requirements, and the system to meet those requirements. This chapter is intended to provide information on each of these areas.

  5. Direct Nitrous Oxide Emission from the Aquacultured Pacific White Shrimp (Litopenaeus vannamei).

    Science.gov (United States)

    Heisterkamp, Ines M; Schramm, Andreas; de Beer, Dirk; Stief, Peter

    2016-07-01

    The Pacific white shrimp (Litopenaeus vannamei) is widely used in aquaculture, where it is reared at high stocking densities, temperatures, and nutrient concentrations. Here we report that adult L. vannamei shrimp emit the greenhouse gas nitrous oxide (N2O) at an average rate of 4.3 nmol N2O/individual × h, which is 1 to 2 orders of magnitude higher than previously measured N2O emission rates for free-living aquatic invertebrates. Dissection, incubation, and inhibitor experiments with specimens from a shrimp farm in Germany indicated that N2O is mainly produced in the animal's gut by microbial denitrification. Microsensor measurements demonstrated that the gut interior is anoxic and nearly neutral and thus is favorable for denitrification by ingested bacteria. Dinitrogen (N2) and N2O accounted for 64% and 36%, respectively, of the nitrogen gas flux from the gut, suggesting that the gut passage is too fast for complete denitrification to be fully established. Indeed, shifting the rearing water bacterial community, a diet component of shrimp, from oxic to anoxic conditions induced N2O accumulation that outlasted the gut passage time. Shrimp-associated N2O production was estimated to account for 6.5% of total N2O production in the shrimp farm studied here and to contribute to the very high N2O supersaturation measured in the rearing tanks (2,099%). Microbial N2O production directly associated with aquacultured animals should be implemented into life cycle assessments of seafood production. The most widely used shrimp species in global aquaculture, Litopenaeus vannamei, is shown to emit the potent greenhouse gas nitrous oxide (N2O) at a particularly high rate. Detailed experiments reveal that N2O is produced in the oxygen-depleted gut of the animal by bacteria that are part of the shrimp diet. Upon ingestion, these bacteria experience a shift from oxic to anoxic conditions and therefore switch their metabolism to the anaerobic denitrification process, which produces N

  6. 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.

  7. Greening the greenhouse grower

    DEFF Research Database (Denmark)

    Staats, Henk; Jansen, Lilian; Thøgersen, John

    2011-01-01

    Growing plants and flowers in greenhouses is a commercial activity that imposes a burden on the environment. Recently a system of registration, control, and licensing has been developed by the sector of greenhouse growers in the Netherlands, acknowledged by the state. The current study was executed...... to understand the achievements of the greenhouse growers within this system. We applied a social-cognitive model to understand intentions to reduce emissions and predict actual pesticide use. The social-cognitive concepts from the model were measured in a questionnaire that was completed by 743 greenhouse...

  8. 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…

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Patrícia Martins

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

  11. 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 ...

  12. 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…

  13. 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 ...

  14. 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...

  15. 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...

  16. 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 ...

  17. 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.

  18. 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....

  19. 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

  20. 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.

  1. 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 ...

  2. 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

  3. Nutrient fate in aquacultural systems for waste treatment

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-08-01

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

  4. Plant Physiology in Greenhouses

    NARCIS (Netherlands)

    Heuvelink, E.; Kierkels, T.

    2015-01-01

    Since 2004 Ep Heuvelink and Tijs Kierkels have been writing a continuing series of plant physiology articles for the Dutch horticultural journal Onder Glas and the international edition In Greenhouses. The book Plant Physiology in Greenhouses consists of 50 of their plant physiology articles. The

  5. Geothermal Greenhouse Information Package

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, K. [P.E.; Boyd, T. [ed.

    1997-01-01

    This package of information is intended to provide a foundation of background information for developers of geothermal greenhouses. The material is divided into seven sections covering such issues as crop culture and prices, operating costs for greenhouses, heating system design, vendors and a list of other sources of information.

  6. The greenhouse effect gases

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the greenhouse effect gases. It presents the greenhouses effect as a key component of the climate system, the impacts of the human activity, the foreseeable consequences of global warming, the Kyoto protocol and Total commitment in the domain. (A.L.B.)

  7. Grappling with greenhouse

    International Nuclear Information System (INIS)

    Mitchell, C.D.

    1992-01-01

    A natural greenhouse effect keeps the Earth at a temperature suitable for life. Some of the gases responsible for the greenhouse effect are increasing at an unprecedented rate because of human activity. These increased levels of greenhouse gases in the atmosphere will strengthen the natural greenhouse effect, leading to an overall warming of the Earth's surface. Global warming resulting from the enhanced greenhouse effect is likely to be obscured by normal climatic fluctuations for another ten years or more. The extent of human-caused climate change will depend largely on future concentrations of greenhouse gases in the atmosphere. In turn, the composition of the atmosphere depends on the release of greenhouse gases. Releases are hard to predict, because they require an understanding of future human activity. The composition of the atmosphere also depends on the processes which remove greenhouse gases from it. This booklet is summarizing the latest research results in the form of climate change scenarios. The present scenarios of change are based on climate models, together with an understanding of how present-day climate, with its inherent natural variability, affects human activities. These scenarios present a coherent range of future possibilities for climate; they are not predictions but they serve as a useful starting point. It is estimated that human-caused climate change will affect all aspects of life in Australia, including our cities, agriculture, pests and diseases, fisheries and natural ecosystems. 15 figs., ills

  8. The greenhouse effect

    International Nuclear Information System (INIS)

    2004-01-01

    In the framework of the sustainable development, this paper presents the greenhouse effect and its impact on the climatic change, the world interest from Rio to Buenos Aires, the human activities producing the carbon dioxide and responsible of the greenhouse effect, the carbon dioxide emission decrease possibilities and shows the necessity of the electric power producers contribution. (A.L.B.)

  9. Towards the semiclosed greenhouse

    NARCIS (Netherlands)

    Hemming, S.

    2009-01-01

    What can we do right now to reduce the consumption of fossil fuels in the greenhouse sector? What technologies should we concentrate on in the future? Researchers, consultants and technology enterprises working with the greenhouse sector have tried to answer these questions in collaboration with the

  10. Risk-informed decision-making analysis for the electrical raceway fire barrier systems on a BWR-4 plant

    International Nuclear Information System (INIS)

    Wu, Ching-Hui; Lin, Tsu-Jen; Kao, Tsu-Mu; Chen, Chyn-Rong

    2003-01-01

    This paper describes a risk-informed decision-making approach used to resolve the fire barrier issue in a BWR-4 nuclear plant where Appendix R separation requirements cannot be met without installing additional fire protection features such as electrical raceway fire barrier system. The related risk measures in CDF (core damage frequency) and LERF (large early release frequency) of the fire barrier issue can be determined by calculating the difference in plant risks between various alternative cases and that met the requirement of the Appendix R. In some alternative cases, additional early-detection and fast-response fire suppression systems are suggested. In some other cases, cable re-routing of some improper layout of non-safety related cables are required. Sets of fire scenarios are re-evaluated more detailed by reviewing the cable damage impact for the BWR-4 plant. The fire hazard model, COMPBRM III-e, is used in this study and the dominant results in risk measures are benchmarked with the CFD code, FDS 2.0, to ensure that the risk impact of fire barrier is estimated accurately in the risk-informed decision making. The traditional deterministic qualitative methods, such as defense-in-depth, safety margin and post-fire safety shutdown capability are also proceeded. The value-impact analysis for proposed alternatives of fire wrapping required by Appendix R has been completed for technical basis of the exemption on Appendix R application. The outcome of the above analysis should be in compliance with the regulatory guidelines (RG) 1.174 and 1.189 for the applications in the risk-informed decision-making of the fire wrapping issues. (author)

  11. Degradation of carbendazim in water via photo-Fenton in Raceway Pond Reactor: assessment of acute toxicity and transformation products.

    Science.gov (United States)

    da Costa, Elizângela Pinheiro; Bottrel, Sue Ellen C; Starling, Maria Clara V M; Leão, Mônica M D; Amorim, Camila Costa

    2018-05-08

    This study aimed at investigating the degradation of fungicide carbendazim (CBZ) via photo-Fenton reactions in artificially and solar irradiated photoreactors at laboratory scale and in a semi-pilot scale Raceway Pond Reactor (RPR), respectively. Acute toxicity was monitored by assessing the sensibility of bioluminescent bacteria (Aliivibrio fischeri) to samples taken during reactions. In addition, by-products formed during solar photo-Fenton were identified by liquid chromatography coupled to mass spectrometry (UFLC-MS). For tests performed in lab-scale, two artificial irradiation sources were compared (UV λ > 254nm and UV-Vis λ > 320nm ). A complete design of experiments was performed in the semi-pilot scale RPR in order to optimize reaction conditions (Fe 2+ and H 2 O 2 concentrations, and water depth). Efficient degradation of carbendazim (> 96%) and toxicity removal were achieved via artificially irradiated photo-Fenton under both irradiation sources. Control experiments (UV photolysis and UV-Vis peroxidation) were also efficient but led to increased acute toxicity. In addition, H 2 O 2 /UV λ > 254nm required longer reaction time (60 minutes) when compared to the photo-Fenton process (less than 1 min). While Fenton's reagent achieved high CBZ and acute toxicity removal, its efficiency demands higher concentration of reagents in comparison to irradiated processes. Solar photo-Fenton removed carbendazim within 15 min of reaction (96%, 0.75 kJ L -1 ), and monocarbomethoxyguanidine, benzimidazole isocyanate, and 2-aminobenzimidazole were identified as transformation products. Results suggest that both solar photo-Fenton and artificially irradiated systems are promising routes for carbendazim degradation.

  12. 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.

  13. Genomic Approaches in Marine Biodiversity and Aquaculture

    Directory of Open Access Journals (Sweden)

    Jorge A Huete-Pérez

    2013-01-01

    Full Text Available Recent advances in genomic and post-genomic technologies have now established the new standard in medical and biotechnological research. The introduction of next-generation sequencing, NGS,has resulted in the generation of thousands of genomes from all domains of life, including the genomes of complex uncultured microbial communities revealed through metagenomics. Although the application of genomics to marine biodiversity remains poorly developed overall, some noteworthy progress has been made in recent years. The genomes of various model marine organisms have been published and a few more are underway. In addition, the recent large-scale analysis of marine microbes, along with transcriptomic and proteomic approaches to the study of teleost fishes, mollusks and crustaceans, to mention a few, has provided a better understanding of phenotypic variability and functional genomics. The past few years have also seen advances in applications relevant to marine aquaculture and fisheries. In this review we introduce several examples of recent discoveries and progress made towards engendering genomic resources aimed at enhancing our understanding of marine biodiversity and promoting the development of aquaculture. Finally, we discuss the need for auspicious science policies to address challenges confronting smaller nations in the appropriate oversight of this growing domain as they strive to guarantee food security and conservation of their natural resources.

  14. 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.

  15. National Greenhouse Gas Emission Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Greenhouse Gas Emission Inventory contains information on direct emissions of greenhouse gases as well as indirect or potential emissions of greenhouse...

  16. The greenhouse effect

    International Nuclear Information System (INIS)

    Berger, A.

    1991-01-01

    The greenhouse effect on earth can be defined as the long wave energy trapped in the atmosphere. Climate forcing and climate system response within which climate feedback mechanisms are contained are determined. Quantitative examples illustrate what could happen if the greenhouse effect is perturbed by human activities, in particular if CO2 atmospheric concentration would double in the future. Recent satellite measurements of the greenhouse effect are given. The net cooling effect of clouds and whether or not there will be less cooling by clouds as the planet warms are also discussed

  17. Through the greenhouse window

    International Nuclear Information System (INIS)

    Townsley, M.

    1989-01-01

    Nuclear power is being promoted as the only answer to the greenhouse effect. However, power station emissions (from fossil-fuel powered stations) account for only a fraction of the total carbon dioxide emissions. And carbon dioxide accounts for only about a half of the global warming effect -the other gases which create the greenhouse effect must also be limited. Nuclear energy is neither a practical nor economic alternative. Energy efficiency and conservation is a far better answer to the greenhouse effect. (U.K.)

  18. Climate, greenhouse effect, energy

    International Nuclear Information System (INIS)

    Henriksen, Thormod; Kanestroem, Ingolf

    2001-01-01

    The book has sections on the sun as energy source, the earth climate and it's changes and factors influencing this, the greenhouse effect on earth and other planets, greenhouse gases and aerosols and their properties and importance, historic climate and paleoclimate, climatic models and their uses and limitations, future climate, consequences of climatic changes, uncertainties regarding the climate and measures for reducing the greenhouse effect. Finally there are sections on energy and energy resources, the use, sources such as fossil fuels, nuclear power, renewable resources, heat pumps, energy storage and environmental aspects and the earth magnetic field is briefly surveyed

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Effects of coastal marsh conversion to shrimp aquaculture ponds on CH4 and N2O emissions

    Science.gov (United States)

    Yang, P.; Bastviken, D.; Lai, D. Y. F.; Jin, B. S.; Mou, X. J.; Tong, C.; Yao, Y. C.

    2017-12-01

    In this study, we compared the CH4 and N2O fluxes from a tidal brackish Cyperus malaccensis marsh ecosystem and nearby shrimp ponds, converted from C. malaccensis marsh in the last 3-4 years, in the Min River estuary of southeast China over the aquaculture period of the year. Significant differences in CH4 and N2O fluxes were observed in space (between brackish marsh and shrimp ponds) and in time (between sampling occasions that were distributed over the aquaculture period). CH4 fluxes from the shrimp ponds were on an average 10-fold higher than from the brackish marsh. N2O emissions, on the other hand, were lower from the shrimp pond (25% of the emissions from the brackish marsh). Accessory data indicates that these patterns were primarily linked to water level variability and temperature (all fluxes), sediment porewater sulfate concentrations (CH4 flux) and total nitrogen concentrations (N2O flux). Our research demonstrates that the coastal marsh ecosystem converted to aquaculture ponds considerably alter emissions of CH4 and N2O and provides input to the global discussion on how to account for emissions from various types of flooded land in greenhouse gas inventories.

  5. Technology Model of Aquaculture Production System

    Science.gov (United States)

    Hor, K. W.; Salleh, S. M.; Abdullah; Ezree, Mohd; Zaman, I.; Hatta, M. H.; Ahmad, S.; Ismail, A. E.; Mahmud, W. A. W.

    2017-10-01

    The high market demand has led to the rapid growth in fish farming. The young generation are inexperienced in determining the estimated results of fish farming and the preparation of fish pond during the period of fish farming. These need a complete guide as their reference which includes the knowledge of fish farming. The main objective of this project is to develop a practical design of real pond appropriate with aquaculture technology and fish farming production. There are three parts of study in this project which include fish farming cage, growth of fish and water quality of fish farming pond. Few of experiments were carried out involved the collection data in terms of growth of fish and parameters of water quality.

  6. Utilisation des "algues-fourrage" en aquaculture

    OpenAIRE

    Chretiennot-dinet, Marie-josèphe; Robert, Rene; His, Edouard

    1986-01-01

    Les travaux concernant l'utilisation d'algues unicellulaires pour la nutrtion de larves et de juvéniles de bivalves d'intérêt commercial sont analysés. Sur une cinquantaine d'espèces d'algues testées, un dizaine seulement sont produites en grande quantité dans des écloseries commerciales sous le non "d'algues fourrage". Les principales espèces employées sont décrites et leurs caractéristiques majeures illustrées. Les critères permettant de retenir une espèce pour son utilisation en aquacultur...

  7. Reproduction of European Eel in Aquaculture (REEL)

    DEFF Research Database (Denmark)

    Tomkiewicz, Jonna; Tybjerg, Lars; Støttrup, Josianne

    for the development of methods to reproduce European eel in aquaculture. Two major projects: Artificial Reproduction of Eels II and III (ROE II and III) succeeded during 2005-2008 to produce viable eggs and larvae that lived up to 12 days. The larvae thereby accomplished the yolk-sac stage and became ready to start...... feeding. The results were in particular promising because they evidenced that methods successfully applied to Japanese eel has a potential for application also to the European eel. ROE II and III were supported by the Ministry of Food, Agriculture and Fisheries and the European Commission through...... the Financial Instrument for Fisheries Guidance (FIFG) and the Danish Food Research Program 2006, respectively. Results: The REEL project accomplished through three series of experiments to consolidate previous results. The longevity of larvae was extended from 12 to 20 days after hatch in first feeding...

  8. Response surface methodology modeling to improve degradation of Chlorpyrifos in agriculture runoff using TiO2 solar photocatalytic in a raceway pond reactor.

    Science.gov (United States)

    Amiri, Hoda; Nabizadeh, Ramin; Silva Martinez, Susana; Jamaleddin Shahtaheri, Seyed; Yaghmaeian, Kamyar; Badiei, Alireza; Nazmara, Shahrokh; Naddafi, Kazem

    2018-01-01

    This paper deals with the use of a raceway pond reactor (RPR) as an alternative photoreactor for solar photocatalytic applications. Raceway pond reactors are common low-cost reactors which can treat large volumes of water. The experiments were carried out with TiO 2 in the agriculture effluent spiked with Chlorpyrifos (CPF) at circumneutral pH. The Response Surface Methodology (RSM) was used to find the optimum process parameters to maximize CPF oxidation from the mathematical model equations developed in this study using R software. By ANOVA, p-value of lack of fit > 0.05 indicated that, the equation was well-fitted. The theoretical efficiency of CPF removal, under the optimum oxidation conditions with UV solar energy of around 697 ± 5.33 lux, was 84.01%, which is in close agreement with the mean experimental value (80 ± 1.42%) confirming that the response model was suitable for the optimization. As far as the authors know, this is the first study of CPF removal using RPR in agriculture runoff at circumneutral pH. Copyright © 2017. Published by Elsevier Inc.

  9. GEOTHERMAL GREENHOUSING IN TURKEY

    Directory of Open Access Journals (Sweden)

    Sedat Karaman

    2016-07-01

    Full Text Available Use of renewable energy resources should be brought forward to reduce heating costs of greenhouses and to minimize the use of ever-depleting fossil fuels. Geothermal energy not only provides the heat required throughout plant growth, but also allow a year-long production. Geothermal resources with several other benefits therefore play significant role in agricultural activities. With regard to geothermal potential and implementation, Turkey has the 7th place in the world and the 1st place in Europe. Majority of country geothermal resources is used in greenhouse heating. The size of geothermal greenhouses increased 5 folds during the last decade and reached to 2500 decare. In this study, current status of geothermal greenhousing of Turkey was presented; problems and possible solutions were discussed.

  10. Photoinactivation of major bacterial pathogens in aquaculture

    Directory of Open Access Journals (Sweden)

    Heyong Jin Roh

    2016-08-01

    Full Text Available Abstract Background Significant increases in the bacterial resistance to various antibiotics have been found in fish farms. Non-antibiotic therapies for infectious diseases in aquaculture are needed. In recent years, light-emitting diode technology has been applied to the inactivation of pathogens, especially those affecting humans. The purpose of this study was to assess the effect of blue light (wavelengths 405 and 465 nm on seven major bacterial pathogens that affect fish and shellfish important in aquaculture. Results We successfully demonstrate inactivation activity of a 405/465-nm LED on selected bacterial pathogens. Although some bacteria were not fully inactivated by the 465-nm light, the 405-nm light had a bactericidal effect against all seven pathogens, indicating that blue light can be effective without the addition of a photosensitizer. Photobacterium damselae, Vibrio anguillarum, and Edwardsiella tarda were the most susceptible to the 405-nm light (36.1, 41.2, and 68.4 J cm−2, respectively, produced one log reduction in the bacterial populations, whereas Streptococcus parauberis was the least susceptible (153.8 J cm−2 per one log reduction. In general, optical density (OD values indicated that higher bacterial densities were associated with lower inactivating efficacy, with the exception of P. damselae and Vibrio harveyi. In conclusion, growth of the bacterial fish and shellfish pathogens evaluated in this study was inactivated by exposure to either the 405- or 465-nm light. In addition, inactivation was dependent on exposure time. Conclusions This study presents that blue LED has potentially alternative therapy for treating fish and shellfish bacterial pathogens. It has great advantages in aspect of eco-friendly treating methods differed from antimicrobial methods.

  11. 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...

  12. 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.

  13. 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...

  14. Climate-simulated raceway pond culturing: quantifying the maximum achievable annual biomass productivity of Chlorella sorokiniana in the contiguous USA

    Energy Technology Data Exchange (ETDEWEB)

    Huesemann, M.; Chavis, A.; Edmundson, S.; Rye, D.; Hobbs, S.; Sun, N.; Wigmosta, M.

    2017-09-13

    Chlorella sorokiniana (DOE 1412) emerged as one of the most promising microalgae strains from the NAABB consortium project, with a remarkable doubling time under optimal conditions of 2.57 hr-1. However, its maximum achievable annual biomass productivity in outdoor ponds in the contiguous United States remained unknown. In order to address this knowledge gap, this alga was cultured in indoor LED-lighted and temperature-controlled raceways in nutrient replete freshwater (BG-11) medium at pH 7 under conditions simulating the daily sunlight intensity and water temperature fluctuations during three seasons in Southern Florida, an optimal outdoor pond culture location for this organism identified by biomass growth modeling. Prior strain characterization indicated that the average maximum specific growth rate (µmax) at 36 ºC declined continuously with pH, with µmax corresponding to 5.92, 5.83, 4.89, and 4.21 day-1 at pH 6, 7, 8, and 9, respectively. In addition, the maximum specific growth rate declined nearly linearly with increasing salinity until no growth was observed above 35 g/L NaCl. In the climate-simulated culturing studies, the volumetric ash-free dry weight-based biomass productivities during the linear growth phase were 57, 69, and 97 mg/L-day for 30-year average light and temperature simulations for January (winter), March (spring), and July (summer), respectively, which corresponds to average areal productivities of 11.6, 14.1, and 19.9 g/m2-day at a constant pond depth of 20.5 cm. The photosynthetic efficiencies (PAR) in the three climate-simulated pond culturing experiments ranged from 4.1 to 5.1%. The annual biomass productivity was estimated as ca. 15 g/m2-day, nearly double the U.S. Department of Energy (DOE) 2015 State of Technology annual cultivation productivity of 8.5 g/m2-day, but this is still significantly below the projected 2022 target of ca. 25 g/m2-day (U.S. DOE, 2016) for economic microalgal biofuel production, indicating the need for

  15. Regional greenhouse climate effects

    International Nuclear Information System (INIS)

    Hansen, J.; Rind, D.; Delgenio, A.; Lacis, A.; Lebedeff, S.; Prather, M.; Ruedy, R.; Karl, T.

    1990-01-01

    The authors discuss the impact of an increasing greenhouse effect on three aspects of regional climate: droughts, storms and temperature. A continuous of current growth rates of greenhouse gases causes an increase in the frequency and severity of droughts in their climate model simulations, with the greatest impacts in broad regions of the subtropics and middle latitudes. But the greenhouse effect enhances both ends of the hydrologic cycle in the model, that is, there is an increased frequency of extreme wet situations, as well as increased drought. Model results are shown to imply that increased greenhouse warming will lead to more intense thunderstorms, that is, deeper thunderstorms with greater rainfall. Emanual has shown that the model results also imply that the greenhouse warming leads to more destructive tropical cyclones. The authors present updated records of observed temperatures and show that the observations and model results, averaged over the globe and over the US, are generally consistent. The impacts of simulated climate changes on droughts, storms and temperature provide no evidence that there will be regional winners if greenhouse gases continue to increase rapidly

  16. 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...

  17. 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 ...

  18. 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

  19. 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.

  20. 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.)

  1. 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.

  2. 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 ...

  3. 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...

  4. 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...

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

    DEFF Research Database (Denmark)

    Nielsen, Rasmus

    2011-01-01

    growth can be achieved by introducing new environmentally friendly water purification systems in Danish fresh water aquaculture. Data Envelopment Analysis is used to investigate whether different water purification systems and farm size influence technical efficiency. The empirical results indicate...

  6. 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...

  7. 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 ...

  8. 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...

  9. 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...

  10. 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 ...

  11. 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

  12. 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...

  13. 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

  14. 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.

  15. Buying greenhouse insurance

    International Nuclear Information System (INIS)

    Manne, A.S.; Richels, R.G.

    1992-01-01

    A growing concern that the increasing accumulation of greenhouse gases will lead to undesirable changes in global climate has resulted in proposals, both in the United States and internationally, to set physical targets for reducing greenhouse gas emissions. But what will these proposals cost? This book outlines a way to think about greenhouse-effect decisions under uncertainty. It describes an insightful model for determining the economic costs of limiting CO 2 emissions produced by burning fossil fuels and provides a solid analytical base for rethinking public policy on the far-reaching issue of global warming. It presents region-by-region estimates of the costs that would underlie an international agreement. Using a computer model known as Global 2100, they analyze the economic impacts of limiting CO 2 emissions under alternative supply and conservation scenarios. The results clearly indicate that a reduction in emissions is not the sole policy response to potential climate change. Following a summary of the greenhouse effect, its likely causes, and possible consequences, this book takes up issues that concern the public at large. They provide an overview of Global 2100, look at how the U.S. energy sector is likely to evolve under business-as-usual conditions and under carbon constraints, and describe the concept of greenhouse insurance. They consider possible global agreements, including an estimate of benefits that might result from trading in an international market in emission rights. They conclude with a technical description directed toward modeling specialists

  16. Tocopherols in Seafood and Aquaculture Products.

    Science.gov (United States)

    Afonso, Cláudia; Bandarra, Narcisa M; Nunes, Leonor; Cardoso, Carlos

    2016-01-01

    Fish products contain various nutritionally beneficial components, namely, ω3-polyunsaturated fatty acids (ω3-PUFA), minerals, and vitamins. Particularly, tocopherols (α-, β-, γ-, and δ-tocopherol) can be provided by seafood and aquaculture products. Hence, this review shows the various aspects of tocopherols in seafood and aquaculture products. For tocopherol determination in these products, HPLC methods coupled with diode array detection in the UV area of the spectrum or fluorescence detection have been shown as sensitive and accurate. These newest methods have helped in understanding tocopherols fate upon ingestion by seafood organisms. Tocopherols pass through the intestinal mucosa mainly by the same passive diffusion mechanism as fats. After absorption, the transport mechanism is thought to consist of two loops. The first loop is dietary, including chylomicrons and fatty acids bound to carrier protein, transporting lipids mainly to the liver. The other is the transport from the liver to tissues and storage sites. Moreover, tocopherol levels in fish organisms correlate with diet levels, being adjusted in fish body depending on diet concentration. For farmed fish species, insufficient levels of tocopherols in the diet can lead to poor growth performance or to nutritional disease. The tocopherol quantity needed as a feed supplement depends on various factors, such as the vitamer mixture, the lipid level and source, the method of diet preparation, and the feed storage conditions. Other ingredients in diet may be of great importance, it has been proposed that α-tocopherol may behave as a prooxidant synergist at higher concentrations when prooxidants such as transition metals are present. However, the antioxidant action of tocopherols outweighs this prooxidant effect, provided that adequate conditions are used. In fact, muscle-based foods containing higher levels of tocopherol show, for instance, higher lipid stability. Besides, tocopherols are important not

  17. Greenhouse effects on Venus

    Science.gov (United States)

    Bell, Peter M.

    Calculations that used Pioneer-Venus measurements of atmosphere composition, temperature profiles, and radiative heating predicted Venus' surface temperature ‘very precisely,’ says the Ames Research Center. The calculations predict not only Venus' surface temperature but agree with temperatures measured at various altitudes above the surface by the four Pioneer Venus atmosphere probe craft.Using Pioneer-Venus spacecraft data, a research team has virtually proved that the searing 482° C surface temperature of Venus is due to an atmospheric greenhouse effect. Until now the Venus greenhouse effect has been largely a theory.

  18. Harnessing greenhouse effect

    International Nuclear Information System (INIS)

    Meunier, F.; Rivet, P.; Terrier, M.F.

    2005-01-01

    This book considers the energy and greenhouse effect questions in a global way. It presents the different methods of fight against the increase of the greenhouse effect (energy saving, carbon sinks, cogeneration,..), describes the main alternative energy sources to fossil fuels (biomass, wind power, solar, nuclear,..), and shows that, even worrying, the future is not so dark as it seems to be and that technical solutions exist which will allow to answer the worldwide growing up energy needs and to slow down the climatic drift. (J.S.)

  19. Greenhouse Warming Research

    DEFF Research Database (Denmark)

    Sørensen, Bent Erik

    2016-01-01

    The changing greenhouse effect caused by natural and anthropogenic causes is explained and efforts to model the behavior of the near-surface constituents of the Earth's land, ocean and atmosphere are discussed. Emissions of various substances and other aspects of human activity influence...... the greenhouse warming, and the impacts of the warming may again impact the wellbeing of human societies. Thus physical modeling of the near-surface ocean-soil-atmosphere system cannot be carried out without an idea of the development of human activities, which is done by scenario analysis. The interactive...

  20. Review of occupational hazards associated with aquaculture.

    Science.gov (United States)

    Myers, Melvin L

    2010-10-01

    Aquaculture is an emerging sector that is associated with most of the same hazards that are present in agriculture generally, but many fish farming tasks entail added danger, including working around water and working at night. Comprehensive studies of these hazards have not been conducted, and substantial uncertainty exists as to the extent of these hazards. The question addressed in this investigation was, "What is known about potential hazardous occupational exposures to aquatic plant and animal farmers?" In this review, causes of death included drowning, electrocution, crushing-related injury, hydrogen sulfide poisoning, and fatal head injury. Nonfatal injuries were associated with slips, trips, and falls; machines; strains and sprains; chemicals; and fires. Risk factors included cranes (tip over and power line contact), tractors and sprayer-equipped all-terrain vehicles (overturn), heavy loads (lifting), high-pressure sprayers, slippery surfaces, rotting waste (hydrogen sulfide production), eroding levees (overturn hazard), storm-related rushing water, diving conditions (bends and drowning), nighttime conditions, working alone, lack of training, lack of or failure to use personal flotation devices, and all-terrain vehicle speeding. Other hazards included punctures or cuts from fish teeth or spines, needlesticks, exposure to low temperatures, and bacterial and parasitic infections .

  1. Defeating diplostomoid dangers in USA catfish aquaculture.

    Science.gov (United States)

    Overstreet, Robin M; Curran, Stephen S

    2004-06-01

    Diplostomoid digenean metacercariae have caused widescale mortalities of channel catfish, Ictalurus punctatus (Rafinesque), at aquaculture farms in Louisiana, Mississippi and Arkansas, USA. Originally, based on a tentative diagnosis, the industry considered the primary harmful agent to be an introduced species from Europe, Bolbophorus confusus (Krause, 1914), frequently reported from the American white pelican, Pelecanus erythrorhynchos Gmelin. Our group has now shown, using ITS 1-2 plus three more-conservative gene fragments, that two sympatric species of Bolbophorus exist in the American white pelican. One, B. damnificus Overstreet et Curran, 2002, infects the musculature of catfish, and the other, probably not B. confusus, does not infect catfish. However, at least four other pathogenic diplostomoids and a clinostomoid infect the catfish, and they use at least four different snail hosts, including the planorbids Planorbella trivolvis (Say) and Gyraulus parvus (Say), the physid Physella gyrina (Say) and a lymnaeid. Two metacercariae, B. damnificus and Bursacetabulus pelecanus Dronen, Tehrany et Wardle, 1999, infect the catfish and mature in the pelican; two others, Austrodiplostomum compactum (Lutz, 1928) and Hysteromorpha cf. triloba (Rudolphi, 1819), mature in cormorants; one, Diplostomum sp., matures in seagulls and at least one, Clinostomum marginatum (Rudolphi, 1819), matures in herons, egrets and other wading birds. Consequently, management of catfish ponds relative to digenean infections requires considerable biological information on the fish, bird, and snail hosts as well as the parasites.

  2. A Layman's Guide to Geothermal Aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kenan C

    1981-01-01

    The following paper is designed as an aid to anyone contemplating a venture into commercially raising giant freshwater prawns, Macrobrachium rosenbergii. Oregon Institute of Technology has been actively involved in a research program to determine the feasibility of such a venture and results to date have been very encouraging. This aquaculture research was initiated in 1975 and was developed as an effort to utilize excess energy from the school’s geothermal heating system. Therefore, most of the information gathered here, will apply to flow-through systems which use geothermal water to maintain a suitable environment for the animals. A study of the market potential for freshwater prawns has been conducted and a favorable response received from wholesale distributors in the Pacific Northwest. Not only is a good market available, but distributors have suggested paying from $4.50 to $5.00 per pound for whole prawns in the size category of 16 to 20 tails to the pound, for a constant fresh supply. By maintaining constant temperatures of 27 degrees Celsius (80 degrees Fahrenheit) ± 1 degree Celsius in our research ponds, we have been able to produce this size prawn in 6 to 8 months.

  3. 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

  4. Smarter greenhouse climate control

    NARCIS (Netherlands)

    Nederhoff, E.M.; Houter, G.

    2011-01-01

    Greenhouse operators strive to be as economic as possible with energy. However, investing in fancy energy-saving equipment is often not cost-effective for smaller operations and in climate zones with mild winters. It is possible, though, for many growers to save energy without buying special

  5. Greenhouse cooling using a rainwater basin under the greenhouse

    NARCIS (Netherlands)

    Campen, J.B.

    2006-01-01

    The objective of the study was to determine the technical and economical aspects of additional applications for a rainwater basin installed under a greenhouse. The installation for cooling the greenhouse can be placed under the greenhouse. Part of the installation consists of a short-term heat store

  6. 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...

  7. Greenhouse production systems for people

    NARCIS (Netherlands)

    Giacomelli, G.A.; Sase, S.; Cramer, R.; Hoogeboom, J.; McKenzie, A.; Parbst, K.; Sacrascia-Mugnozza, G.; Selina, P.; Sharp, D.A.; Voogt, J.O.; Weel, van P.A.; Mears, D.

    2012-01-01

    Environmentally sound greenhouse production requires that: demand for market products is understood; greenhouse design addresses the climate circum-stances; input resources are available and consumed efficiently, and; there must be a reasonable balance of production products to the environmental

  8. Nuclear energy and greenhouse effect

    International Nuclear Information System (INIS)

    Strub, R.A.

    1991-01-01

    The contribution of nuclear power plants against the greenhouse effects is evaluated, not only nuclear energy is unable to fight greenhouse effect increase but long life wastes endanger environment. 8 refs

  9. Greenhouse Gas Data Publication Tool

    Data.gov (United States)

    U.S. Environmental Protection Agency — This tool to gives you access to greenhouse gas data reported to EPA by large facilities and suppliers in the United States through EPA's Greenhouse Gas Reporting...

  10. Aquaculture investigations with nuclear energy techniques

    International Nuclear Information System (INIS)

    Heredia Salazar, Brunilda

    1997-01-01

    The culture of aquatic organisms, especially that of fishes under controlled conditions, up to their harvesting, processing, commercialization and consumption, has been pointed out as an activity that produces a lot of benefits, among them: the obtention high proteic valued food, the incorporation to the economy of lands not usefull for agriculture activities, the increment of fishing resources, the recycling of organic matter produced in the units, the regional development, the generation of employment, technologies and foreign currencies. Several research areas are identified that can be developed, using the nuclear technologies, for example in the reproduction, nutrition, diagnose and control of illnesses, environmental monitoring and quality certification of products. In the concerning to the Venezuelan aquaculture, investigations are required that need to use those techniques. For example: 1) Production of autochthonous inductive agents, by means of radioinmunoenssay (RIA), to determine the gonadotropines coming from the hypophysis of fish cultivated with the purpose of gathering the glands in its best moment, to generate the final maturation and spawn in autochthonous species. 2) Genetic improvement of cultivated species through the knowledge of the genetic load of different lines and breeds found in the natural means, and to achieve its maintenance to solve inbreeding problems, in autochthonous species aswell in as in exotic ones, by the use of marking techniques (ADE, RFLA and microsatellite techniques). 3) Nutritional and feeding studies of species under commertial culture, especially on the effect of the aflatoxins in the inputs or the portions, substances that influence in a negative way the aquatic nutrition. In this case, competitive immunoassays of enzymes bounded (ELISA) and radioinmunoessays. 4) Illness diagnose, by means of the ELISA kit, specifically of the more common illness in fishes cultivated in the country [es

  11. 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.

  12. 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)

  13. 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.

  14. 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

  15. Localized climate control in greenhouses

    NARCIS (Netherlands)

    Booij, P.S.; Sijs, J.; Fransman, J.E.

    2012-01-01

    Strategies for controlling the indoor climate in greenhouses are based on a few sensors and actuators in combination with an assumption that climate variables, such as temperature, are uniform throughout the greenhouse. While this is already an improper assumption for conventional greenhouses, it

  16. 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...

  17. 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...

  18. 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...

  19. 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.

  20. 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...

  1. 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

  2. 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

  3. 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.

  4. The greenhouse challenge

    International Nuclear Information System (INIS)

    Harrington, Ph.

    1999-01-01

    At Kyoto, Australia was successful in gaining acceptance for a differentiated response to climate change which takes account of our special circumstances and allows for an 8% rise in emissions above 1990 levels by 2008 - 2012. This outcome is both environmentally effective but also responsible from the perspective of Australia's economic and trade interests. While our target is achievable it will require significant efforts on the part of industry, all levels of government and the wider community to move towards best practice in managing our greenhouse gas emissions. At the same time, it will provide an incentive for industry and businesses to further improve their efficiency and perhaps even to capture new opportunities that may present themselves. An outline of the National Greenhouse Strategy is given and some of the many implications for the minerals and energy sector are discussed

  5. Pragmatics in the greenhouse

    Energy Technology Data Exchange (ETDEWEB)

    Grubb, M.J.; Victor, D.G.; Hope, C.W. (Royal Institute of International Affairs, London (UK))

    1991-12-05

    Negotiations towards a global framework convention on climate change are hampered by the range of greenhouse gases, sources and sinks. The US government promotes a comprehensive approach to climate change which provides flexibility but faces obstacles arising from the different characteristics of the sources and sinks involved, and uncertainties in attempting to estimate and compare the radiative impacts of different gases. Relying on approximations to enable a comprehensive approach is unrealistic for two reasons: monitoring and revision. The comprehensive approach is a worthwhile goal but is not yet fully practicable. Two lists are suggested - a quantified list for CFCs and CO{sub 2} and a transition list. Frequent renegotiation would be necessary. With this approach an overall goal for controlling the magnitude and rate of change in greenhouse forcing is possible. 12 refs., 1 fig.

  6. Greenhouse and Energy

    International Nuclear Information System (INIS)

    Swaine, D.J.

    1990-01-01

    The book is based on papers at the conference held at Macquarie University, Australia, in December 1989. The topics include energy aspects of the greenhouse effect, effects of reduction of carbon dioxide, methane emissions, sources of energy production, various aspects of electricity, liquid building, new technology, energy management and environmental and sociological aspects. Whilist the emphasis is on Australian conditions, the approaches are of relevance to other countries. Contains lists of referees and participants. Twenty-three papers have been separately indexed

  7. Greenhouse gas strategy

    International Nuclear Information System (INIS)

    2001-03-01

    Because the overall effects of climate change will likely be more pronounced in the North than in other parts of the country, the Government of the Northwest Territories considers it imperative to support global and local actions to reduce greenhouse gas emissions. Government support is manifested through a coordinating role played by senior government representatives in the development of the NWT Greenhouse Gas Strategy, and by participation on a multi-party working committee to identify and coordinate northern actions and to contribute a northern perspective to Canada's National Climate Change Implementation Strategy. This document outlines the NWT Government's goals and objectives regarding greenhouse gas emission reduction actions. These will include efforts to enhance awareness and understanding; demonstrate leadership by putting the Government's own house in order; encouraging action across sectors; promote technology development and innovation; invest in knowledge and building the foundation for informed future decisions. The strategy also outlines the challenges peculiar to the NWT, such as the high per person carbon dioxide emissions compared to the national average (30 tonnes per person per year as opposed to the national average of 21 tonnes per person per year) and the increasing economic activity in the Territories, most of which are resource-based and therefore energy-intensive. Appendices which form part of the greenhouse gas strategy document, provide details of the potential climate change impact in the NWT, a detailed explanation of the proposed measures, an emission forecast to 2004 from industrial processes, fuel combustion and incineration, and a statement of the official position of the Government of the NWT on climate change

  8. Ozone: The secret greenhouse gas

    International Nuclear Information System (INIS)

    Berntsen, Terje; Tjernshaugen, Andreas

    2001-01-01

    The atmospheric ozone not only protects against harmful ultraviolet radiation; it also contributes to the greenhouse effect. Ozone is one of the jokers to make it difficult to calculate the climatic effect of anthropogenic emissions. The greenhouse effect and the ozone layer should not be confused. The greenhouse effect creates problems when it becomes enhanced, so that the earth becomes warmer. The problem with the ozone layer, on the contrary, is that it becomes thinner and so more of the harmful ultraviolet radiation gets through to the earth. However, ozone is also a greenhouse gas and so the greenhouse effect and the ozone layer are connected

  9. 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...

  10. 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...

  11. 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...

  12. 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 ...

  13. 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 ...

  14. 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

  15. 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 ...

  16. Support to the CGIAR Program on Aquaculture | CRDI - Centre de ...

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

    More than 700 million people depend on aquatic agricultural systems (AAS) for their livelihood. These are diverse farming systems that include a mix of cultivation, livestock-raising, aquaculture, fishing, and gathering natural resources such as fruits, seeds, timber and wildlife. However, there are many constraints that ...

  17. Boosting aquaculture production systems in Osun state: Role of ...

    African Journals Online (AJOL)

    This scenario leaves a high percentage of the population who depend on fish and fish products food insecure, and thus, the need to boost aquaculture production to argument the supply from the wild. The study therefore looks into the possibility of boosting the production systems through the use of micro-credit and ...

  18. Peace Corps Aquaculture Training Manual. Training Manual T0057.

    Science.gov (United States)

    Peace Corps, Washington, DC. Information Collection and Exchange Div.

    This Peace Corps training manual was developed from two existing manuals to provide a comprehensive training program in fish production for Peace Corps volunteers. The manual encompasses the essential elements of the University of Oklahoma program that has been training volunteers in aquaculture for 25 years. The 22 chapters of the manual are…

  19. 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

  20. 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 ...

  1. Aquaculture: A Course of Study for Sand Point Secondary School.

    Science.gov (United States)

    Alaska State Dept. of Education, Juneau. Office of Public Information and Publications.

    This program is designed to involve students in the economy of their community. It combines an interdisciplinary educational program with practical field and laboratory experience. This program provides opportunities in the area of aquaculture, controlled cultivation of marketable species and the total ecological corrections necessary to maintain…

  2. A comparison of Asian aquaculture products using statistically supported LCA

    NARCIS (Netherlands)

    Henriksson, P.J.G.; Rico, A.; Zhang, W.; Al-Nahid, A.; Newton, R.; Phan, L.T.; Zhang, Z.; Jaithiang, J.; Dao, H.M.; Phu, T.M.; Little, D.C.; Murray, F.J.; Satapornvanit, K.; Liu, L.; Liu, Q.; Haque, M.M.; Kruijssen, F.; de Snoo, G.R.; Heijungs, R.; van Bodegom, P.

    2015-01-01

    We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different

  3. Implications of water pollution for aquacultural development in Nigeria

    African Journals Online (AJOL)

    Pollution is an age – long problem which has become wide spread due to increase in human population, expanding human settlement and advances in production technologies. Similarly, aquaculture is also on the increase but as a result of increase in the demand of cheap, high quality protein necessitated by high ...

  4. 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

  5. Small-scale Aquaculture to Strengthen Food Security in Cambodia ...

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

    Small-scale Aquaculture to Strengthen Food Security in Cambodia (CIFSRF) ... for their families' consumption in the same ponds as large fish, which can be sold for income. ... The project also studies opportunities to scale up the model for broader use ... Assessing improvements in nutrition outcomes following agricultural ...

  6. 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.

  7. Exploring fish microbial communities to mitigate emerging diseases in aquaculture

    NARCIS (Netherlands)

    Bruijn, de Irene; Liu, Yiying; Wiegertjes, Geert F.; Raaijmakers, Jos M.

    2018-01-01

    Aquaculture is the fastest growing animal food sector worldwide and expected to further increase to feed the growing human population. However, existing and (re-)emerging diseases are hampering fish and shellfish cultivation and yield. For many diseases, vaccination protocols are not in place and

  8. 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...

  9. 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 ...

  10. 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 ...

  11. Environmental risk assessment of veterinary medicines used in Asian aquaculture

    NARCIS (Netherlands)

    Rico, A.

    2014-01-01

    One of the major constraints for the development and expansion of the Asian aquaculture industry has been the proliferation of disease outbreaks. To overcome this issue, a wide range of veterinary medicines including antibiotics, parasiticides and medical disinfectants have been

  12. 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

  13. The perception of aquaculture on the Swedish West Coast

    DEFF Research Database (Denmark)

    Thomas, Jean-Baptiste E.; Nordström, Leif Jonas; Risén, Emma

    2017-01-01

    neutral responses. On the whole, respondents were favourable to the depicted scenario. Finally, it was found that the high-awareness group tended to be more supportive than the low or medium-awareness groups, hinting at the benefits of increasing awareness to reduce public aversion and to support...... a sustainable development of aquaculture on the Swedish West Coast....

  14. Food Security, Fisheries and Aquaculture in the Bolivian Amazon ...

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

    Indigenous communities involved in fisheries and aquaculture are among the most food insecure in the Bolivian Amazon. Although fish could be the main source of protein, it is often not part of the local diet. This project - supported by the Canadian International Food Security Research Fund (CIFSRF), a joint program of ...

  15. Derivation of economic values for production traits in aquaculture species

    NARCIS (Netherlands)

    Janssen, K.P.E.; Berentsen, P.B.M.; Besson, M.B.; Komen, J.

    2017-01-01

    Background:
    In breeding programs for aquaculture species, breeding goal traits are often weighted based on the desired gains but economic gain would be higher if economic values were used instead. The objectives of this study were: (1) to develop a bio-economic model to derive economic values

  16. 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 ...

  17. 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

  18. 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.

  19. Rice field for the treatment of pond aquaculture effluents | Wang ...

    African Journals Online (AJOL)

    We conducted an experiment to evaluate the efficiency of rice fields in treating pond aquaculture effluent and its responses to different fertilizer treatments. Four treatments was considered in the experiment: no rice planted as the control (CT); rice planted and no fertilizer input (RE); rice planted and a rate of approximately ...

  20. 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

  1. 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.

  2. 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 ...

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. Greenhouse effect: Myth or reality

    International Nuclear Information System (INIS)

    Martin, J.L.

    1992-01-01

    This paper debates on greenhouse effect controversy. Natural greenhouse effect is beneficent but additional greenhouse effect, in relation with human activities, can present a major risk for humanity. However an international agreement is difficult owing to the enormous costs which could not be endured by South economies. A tax on carbon dioxide emissions would have for consequence a wave of industrial delocalizations without precedent with important unemployment in Europe and no impact on additional greenhouse effect because it is a radiative effect and it is not a classic local chemical pollution. 11 refs., 10 figs

  8. OPIC Greenhouse Gas Emissions Inventory

    Data.gov (United States)

    Overseas Private Investment Corporation — Independent analysis details quantifying the greenhouse gas ("GHG") emissions directly attributable to projects to which the Overseas Private Investment Corporation...

  9. 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.

  10. Test of a non-physical barrier consisting of light, sound, and bubble screen to block upstream movement of sea lamprey in an experimental raceway

    Science.gov (United States)

    Miehls, Scott M.; Johnson, Nicholas S.; Hrodey, Pete J.

    2017-01-01

    Control of the invasive Sea Lamprey Petromyzon marinus is critical for management of commercial and recreational fisheries in the Laurentian Great Lakes. Use of physical barriers to block Sea Lampreys from spawning habitat is a major component of the control program. However, the resulting interruption of natural streamflow and blockage of nontarget species present substantial challenges. Development of an effective nonphysical barrier would aid the control of Sea Lampreys by eliminating their access to spawning locations while maintaining natural streamflow. We tested the effect of a nonphysical barrier consisting of strobe lights, low-frequency sound, and a bubble screen on the movement of Sea Lampreys in an experimental raceway designed as a two-choice maze with a single main channel fed by two identical inflow channels (one control and one blocked). Sea Lampreys were more likely to move upstream during trials when the strobe light and low-frequency sound were active compared with control trials and trials using the bubble screen alone. For those Sea Lampreys that did move upstream to the confluence of inflow channels, no combination of stimuli or any individual stimulus significantly influenced the likelihood that Sea Lampreys would enter the blocked inflow channel, enter the control channel, or return downstream.

  11. Large-scale biodiesel production using flue gas from coal-fired power plants with Nannochloropsis microalgal biomass in open raceway ponds.

    Science.gov (United States)

    Zhu, Baohua; Sun, Faqiang; Yang, Miao; Lu, Lin; Yang, Guanpin; Pan, Kehou

    2014-12-01

    The potential use of microalgal biomass as a biofuel source has raised broad interest. Highly effective and economically feasible biomass generating techniques are essential to realize such potential. Flue gas from coal-fired power plants may serve as an inexpensive carbon source for microalgal culture, and it may also facilitate improvement of the environment once the gas is fixed in biomass. In this study, three strains of the genus Nannochloropsis (4-38, KA2 and 75B1) survived this type of culture and bloomed using flue gas from coal-fired power plants in 8000-L open raceway ponds. Lower temperatures and solar irradiation reduced the biomass yield and lipid productivities of these strains. Strain 4-38 performed better than the other two as it contained higher amounts of triacylglycerols and fatty acids, which are used for biodiesel production. Further optimization of the application of flue gas to microalgal culture should be undertaken. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. About greenhouse effect origins

    International Nuclear Information System (INIS)

    Arrhenius, S.; Chamberlin, Th.; Croll, J.; Fourier, J.; Pouillet, C.; Tyndall, J.

    2009-01-01

    In order to understand and decipher the ecological crisis in progress, an historical prospect of its origins and evolution at the worldwide scale is necessary. This book gathers seven founder articles (including 4 original translations), harbingers of the present day climate change. Written during the 19. century by famous scientists like Joseph Fourier, Claude Pouillet, James Croll, John Tyndall, Svante Arrhenius and Thomas Chamberlin, they relate a century of major progress in the domain of Earth's sciences in praise of these scientists. This book allows to (re)discover these texts: discovery of the greenhouse effect principle (Fourier), determination of solar radiation absorption by the atmosphere (Pouillet), rivalry between the astronomical theory of glacial cycles (Croll) and the carbon dioxide climatic theory (Tyndall), influence of the CO 2 concentration in the atmosphere on the global warming (Arrhenius), and confirmation of the major role of CO 2 in the Earth's temperature regulation (Chamberlin). (J.S.)

  13. Greenhouse effect and climate

    International Nuclear Information System (INIS)

    Flohn, H.

    1987-01-01

    Model calculations with different marginal conditions and different physical processes do, on the basis of realistic assumptions, result in a temperature rise of 3 ± 1.5degC at doubling carbon dioxide concentrations. Temperatures are increasing even more due to the presence of trace gases contributing to the greenhouse effect. They are assumed to be having a share of 100% in the carbon dioxide effect (additive) in 30-40 years from now. According to the model calculations the CO 2 increase from about 280 ppm around 1850 to 345 ppm (1985) is equal to a globally averaged temperature rise of 0.5-0.7degC. As the data obtained before 1900 were incomplete and little representative climatic analyses cannot be considered to have been effective but after that time. However, considering the additional influence of other climatic effects such as vulcanism the temperature rise satisfactorily corresponds to the values obtained since 1900. (orig./HP) [de

  14. Holistic greenhouse gas management

    Energy Technology Data Exchange (ETDEWEB)

    Read, P. [Dept. of Applied and International Economics, Massey Univ. (New Zealand); Parshotam, A. [Inst. of Fundamental Sciences, Massey Univ. (New Zealand)

    2005-07-01

    A holistic greenhouse gas management strategy is described. The first stage is the growth of a large-scale global bio-energy market with world trade in bio-fuels and with a strategic stock of biomass raw material in new plantation forests. Later stages, more costly - as needs may be in response to possible future precursors of abrupt climate change - would involve linking CO2 capture and sequestration to bio-energy, yielding a negative emissions energy system. Illustrative calculations point to the feasibility of a return to pre-industrial CO{sub 2} levels before mid-century. This result is subject to significant caveats, but, prima facie, the first stage can provide several environmental and socio-economic side-benefits while yielding a positive financial return if oil prices remain above 35$/bbl. The vision is that the polluter pays principle can be turned to a greening of the earth. (orig.)

  15. Greenhouse gas trading

    Energy Technology Data Exchange (ETDEWEB)

    Drazilov, P. [Natsource-Tullett Emissions Brokerage, Toronto, ON (Canada)

    2001-07-01

    Natsource-Tullett Emissions Brokerage is a market leader in natural gas, electricity, coal, and weather, emissions with a total of more than $2 billion by volume in emissions transactions in the United States, Canada, Australia, Japan, and Europe. This power point presentation addressed issues dealing with global warming, the Kyoto Protocol, and explained where we are in terms of reaching commitments for the first compliance period between 2008-2012. The paper focused on international emissions trading (IET), joint implementation (JI) and the clean development mechanism (CDM) and explained how greenhouse gases are traded. Emissions trading refers to the trade of carbon dioxide, methane, nitrous oxides, perfluoro-carbons, hydrofluorocarbons, and sulphur hexafluorides. The motivational drivers for trading were outlined in terms of liability for buyers and assets for sellers. To date, trading activity is nearly 120 transactions with nearly 70 million tons of carbon dioxide equivalent. tabs., figs.

  16. Energy conserving dehumidification of greenhouses

    NARCIS (Netherlands)

    Zwart, de H.F.

    2014-01-01

    As greenhouses become better insulated and increasingly airtight, the humidity of the inside air rises easily and may become unfavourably high. Therefore, most greenhouses frequently open their vents to remove the moisture excess. When heated, opening the vents will increase the energy consumption.

  17. Has your greenhouse gone virtual?

    Science.gov (United States)

    Virtual Grower is a free decision-support software program available from USDA-ARS that allows growers to build a virtual greenhouse. It was initially designed to help greenhouse growers estimate heating costs and conduct simple simulations to figure out where heat savings could be achieved. Featu...

  18. Greenhouse gases and global warming

    International Nuclear Information System (INIS)

    1995-01-01

    From previous articles we have learned about the complexities of our environment, its atmosphere and its climate system. we have also learned that climate change and, therefore global warm and cool periods are naturally occurring phenomena. Moreover, all scientific evidence suggests that global warming, are likely to occur again naturally in the future. However, we have not yet considered the role of the rates of climate change in affecting the biosphere. It appears that how quickly the climate changes may be more important than the change itself. In light of this concern, let us now consider the possibility that, is due to human activity. We may over the next century experience global warming at rates and magnitudes unparalleled in recent geologic history. The following questions are answered; What can we learn from past climates? What do we know about global climates over the past 100 years? What causes temperature change? What are the greenhouse gases? How much have concentration of greenhouse gases increased in recent years? Why are increases in concentrations of greenhouse of concern? What is the e nhanced greenhouse effect ? How can human activity impact the global climate? What are some reasons for increased concentrations of greenhouse gases? What are fossil fuel and how do they transform into greenhouse gases? Who are the biggest emitters of greenhouse gases? Why are canada per capita emissions of greenhouse gases relatively high? (Author)

  19. 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…

  20. 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.

  1. 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.

  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. 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.)

  4. 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...

  5. Turkish tomato greenhouse gets geothermal heating

    NARCIS (Netherlands)

    Sikkema, A.; Maaswinkel, R.H.M.

    2011-01-01

    Wageningen UR Greenhouse Horticulture will set up an ultramodern greenhouse in Turkey, together with Dutch greenhouse builders and contractors. Geothermal energy will be used there to provide heat and carbon dioxide for tomato cultivation.

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

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

    À l'heure actuelle, près de la moitié des animaux aquatiques que consomment les humains sont issus de l'aquaculture, une proportion qui est appelée à augmenter. Une grande partie de la production aquacole mondiale se trouve en Asie tropicale et subtropicale et constitue une importante source d'emploi et de sécurité ...

  7. Dietary carbohydrates and denitrification in recirculating aquaculture systems

    OpenAIRE

    Meriac, A.

    2014-01-01

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

  8. Permanent Advisory Network for Diseases in Aquaculture (PANDA)

    OpenAIRE

    Arzul, Isabelle; Ariel, E.; Hill, B.

    2005-01-01

    The PANDA project aims to establish a permanent network of aquatic animal health specialists (researchers and diagnosticians) to provide a forum for the debate of issues concerning diseases in European aquaculture, and to communicate the results of these discussions to the European Commission with provision of advice on EU policy and legislation for aquatic animal health. PANDA consists of five scientific work packages: risk analysis, epidemiology, diagnosis, environmentally safe strategies f...

  9. Industrial agglomeration and production costs in Norwegian salmon aquaculture

    OpenAIRE

    Tveterås, Ragnar

    2002-01-01

    During the last decade, empirical evidence of regional agglomeration economies has emerged for some industries. This paper argues that externalities from agglomeration are not only present in some manufacturing and service sectors, but can also occur in primary industries, such as aquaculture. Econometric analyses in this literature have primarily estimated rather restrictive production function specifications on aggregated industry data. Here, cost functions are estimated o...

  10. Effects of regional agglomeration of salmon : aquaculture on production costs

    OpenAIRE

    Tveterås, Ragnar

    2001-01-01

    During the last decade empirical evidence of regional agglomeration economies has emerged for some industries. This report argues that externalities from agglomeration are not only present in some manufacturing and service sectors, but can also occur in primary industries such as aquaculture. Econometric analyses in this literature have primarily estimated production functions on aggregated industry data. Here, cost functions are estimated on firm level observations of Norwegian salmon aquacu...

  11. Aquaculture as a part of a multi-use platform

    DEFF Research Database (Denmark)

    Christensen, Erik Damgaard; Svenstrup Petersen, Ole; Aarup Ahrensberg, Nick

    2014-01-01

    European oceans will be subject to massive development of marine infrastructure in the near future. The most obvious is the energy facilities e.g. offshore wind farms, exploitation of wave energy, expansion of electricity connections, and also further development and implementation of marine...... aquaculture. These developments urgently require effective marine technology and governance solutions to facilitate installation, operation and maintenance of these novel offshore activities. Simultaneously, both economic costs and environmental impact have to remain within acceptable limits, in order...

  12. Continuous host-macroparasite models with application to aquaculture

    Directory of Open Access Journals (Sweden)

    Catherine Bouloux Marquet

    2004-11-01

    Full Text Available We study a continuous deterministic host-macroparasite system which involves populations of hosts, parasites, and larvae. This system leads to a countable number of partial differential equations that under certain hypotheses, is reduced to finitely many equations. Also we assume hypotheses to close the system and to define the global dynamics for the hosts. Then, we analyze the spatially homogeneous model without demography (aquaculture hypothesis, and show some preliminary results for the spatially structured model.

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

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

    Ce projet porte sur l'élevage du tilapia dans de petits étangs fermiers ou des cages flottantes dans les rivières et les réservoirs du nord de la Thaïlande. Les chercheurs exploreront des façons d'adapter les pratiques aquacoles aux changements climatiques et analyseront la valeur de l'aquaculture comme stratégie ...

  14. Fish to 2030 : The Role and Opportunity for Aquaculture

    OpenAIRE

    Kobayashi, Mimako; Msangi, Siwa; Batka, Miroslav; Vannuccini, Stefania; Dey, Madan M.; Anderson, James L.

    2015-01-01

    Seafood sector can contribute to the global food supply in an important way, and provide an important source of animal protein. Based on observed regional trends in seafood production and consumption and using a global, partial-equilibrium, multi-market model, this study investigates what the global seafood market may look like in 2030. The model projects that the total fish supply will increase from 154 million tons in 2011 to 186 million tons in 2030, with aquaculture entirely responsible f...

  15. 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.

  16. 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. ?

  17. 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

  18. Politics in the greenhouse

    International Nuclear Information System (INIS)

    Oberthuer, S.

    1993-01-01

    Chapter 1 gives an introduction into the problems surrounding the man-made greenhouse effect, the emphasis being on those features that were significant for the course for the international talks. Chapter 2 describes the course of the talks, giving particular attention to the standpoints of the different protagonists. Further the outcome of the talks is presented. Factors that exerted on influence on the standpoints of the protagonists and on the course of the climate talks are examined in Chapter 3 with special consideration to the interests of the individual protagonists and the international constellation of interests, the values supported by the protagonists and the institutional conditions bearing on the course of the talks. Chapter 4 attempts to explain the process of coming to terms about the international climate convention and the results of this process. This is followed in Chapter 5 by a discussion of the room for manoeuvre and possible tendencies of development of the international alliance for climate protection created by the convention. (HSCH) [de

  19. Climate - Greenhouse effect - Energy

    International Nuclear Information System (INIS)

    Henriksen, Thormod; Kanestroem, Ingolf

    2001-01-01

    This book explains what is understood by climate systems and the concept of greenhouse effect. It also gives a survey of the world's energy consumption, energy reserves and renewable energy sources. Today, 75 - 80 per cent of the world's energy consumption involves fossil fuel. These are the sources that cause the CO 2 emissions. What are the possibilities of reducing the emissions? The world's population is increasing, and to provide food and a worthy life for everybody we have to use more energy. Where do we get this energy from without causing great climate changes and environmental changes? Should gas power plants be built in Norway? Should Swedish nuclear power plants be shut down, or is it advisable to concentrate on nuclear power, worldwide, this century, to reduce the CO 2 emissions until the renewable energy sources have been developed and can take over once the petroleum sources have been depleted? The book also discusses the global magnetic field, which protects against particle radiation from space and which gives rise to the aurora borealis. The book is aimed at students taking environmental courses in universities and colleges, but is also of interest for anybody concerned about climate questions, energy sources and living standard

  20. (Limiting the greenhouse effect)

    Energy Technology Data Exchange (ETDEWEB)

    Rayner, S.

    1991-01-07

    Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to the forefront of the scientific and policy communities than hitherto.

  1. Greenhouse gas trading starts up

    Science.gov (United States)

    Showstack, Randy

    While nations decide on whether to sign on to the Kyoto Protocol on climate change, some countries and private companies are moving forward with greenhouse gas emissions trading.A 19 March report, "The Emerging International Greenhouse Gas Market," by the Pew Center on Global Climate Change, reports that about 65 greenhouse gas emissions trades for quantities above 1,000 metric tons of carbon dioxideequivalent already have occurred worldwide since 1996. Many of these trades have taken place under a voluntary, ad hoc framework, though the United Kingdom and Denmark have established their own domestic emissions trading programs.

  2. 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....

  3. 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...

  4. 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.

  5. 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.

  6. GREENHOUSE-GROWN CAPE GOOSEBERRY

    African Journals Online (AJOL)

    /2006 S 4,00. Printed in Uganda. All rights reserved O2006, African Crop Science Society. SHORT COMMINICATION. EFFECT OF GIBBERRELLIC ACID ON GROWTH AND FRUIT YIELD OF. GREENHOUSE-GROWN CAPE GOOSEBERRY.

  7. Transit Greenhouse Gas Management Compendium

    Science.gov (United States)

    2011-01-12

    This Compendium provides a framework for identifying greenhouse gas (GHG) reduction opportunities while highlighting specific examples of effective GHG reduction practices. The GHG savings benefits of public transit are first described. GHG saving op...

  8. Quotation systems for greenhouse gases

    International Nuclear Information System (INIS)

    Trong, Maj Dang

    2000-01-01

    The article surveys recommendations from a Norwegian committee for implementing at a national level, the Kyoto protocol aims for reducing the total emissions of greenhouse gases from the industrial countries through quotation systems

  9. 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

  10. Greenhouses and their humanizing synergies

    Science.gov (United States)

    Haeuplik-Meusburger, Sandra; Paterson, Carrie; Schubert, Daniel; Zabel, Paul

    2014-03-01

    Greenhouses in space will require advanced technical systems of automatic watering, soil-less cultivation, artificial lighting, and computerized observation of plants. Functions discussed for plants in space habitats include physical/health requirements and human psychology, social cohesion, as well as the complex sensorial benefits of plants for humans. The authors consider the role of plants in long-term space missions historically since 1971 (Salyut 1) and propose a set of priorities to be considered within the design requirements for greenhouses and constructed environments given a range of benefits associated with plant-human relationships. They cite recent research into the use of greenhouses in extreme environments to reveal the relative importance of greenhouses for people living in isolated locations. Additionally, they put forward hypotheses about where greenhouses might factor into several strata of human health. In a recent design-in-use study of astronauts' experiences in space habitats discussed in Architecture for Astronauts (Springer Press 2011) it was found that besides the basic advantages for life support there are clearly additional "side benefits" for habitability and physical wellbeing, and thus long-term mission success. The authors have composed several key theses regarding the need to promote plant-human relationships in space, including areas where synergy and symbiosis occur. They cite new comprehensive research into the early US Space Program to reveal where programmatic requirements could be added to space architecture to increase the less quantifiable benefits to astronauts of art, recreation, and poetic engagement with their existential condition of estrangement from the planet. Specifically in terms of the technological requirements, the authors propose the integration of a new greenhouse subsystem component into space greenhouses—the Mobile Plant Cultivation Subsystem—a portable, personal greenhouse that can be integrated

  11. The Greenhouse Effect Does Exist!

    OpenAIRE

    Ebel, Jochen

    2009-01-01

    In particular, without the greenhouse effect, essential features of the atmospheric temperature profile as a function of height cannot be described, i.e., the existence of the tropopause above which we see an almost isothermal temperature curve, whereas beneath it the temperature curve is nearly adiabatic. The relationship between the greenhouse effect and observed temperature curve is explained and the paper by Gerlich and Tscheuschner [arXiv:0707.1161] critically analyzed. Gerlich and Tsche...

  12. Greenhouse Earth: A Traveling Exhibition

    International Nuclear Information System (INIS)

    Booth, W.H.; Caesar, S.

    1992-09-01

    The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a ''demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a ''satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change

  13. 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...

  14. Food intake rate and delivery strategy in aquaculture

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In aquaculture, it is important to estimate in advance how much food cultured animals would take. The rate of food consumption by cultured animals to available food amount is defined as the food intake rate (FIR) in this paper. To some extents, FIR reflects the quality of food, the health of cultured animals and the delivery efficiency. In practice, it is difficult to estimate in advance the accurate quantity of food that cultured animal needs. Usually, food is provided more than the need by animals, causing excess food that may pollute water and environment. Our experiments in past years show that FIR at 80% is recommended.

  15. Relance de l'aquaculture au Sri Lanka | IDRC - International ...

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

    29 avr. 2016 ... Aquaculture au Sri Lanka. L'adoption de l'ostréiculture dans deux collectivités côtières du Sri Lanka a donné lieu aux premières exportations d'huîtres du pays. Au Sri Lanka, le gouvernement a pour objectif de doubler la consommation de poisson par personne, de 11 kilos à 22 kilos par année, d'ici à la fin ...

  16. 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.

  17. 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...

  18. 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

    Mono-specific aquaculture effluents contain high concentrations of nutrients and organic matter, which affect negatively the water quality of the recipient ecosystems. A fundamental feature of water quality is its transparency. The fraction of dissolved organic matter that absorbs light is named chromophoric dissolved organic matter (CDOM). A sustainable alternative to mono-specific aquaculture is the multitrophic aquaculture that includes species trophically complementary named "extractive" species that uptake the waste byproducts. Sea cucumbers are recognized as efficient extractive species due to the consumption of particulate organic matter (POM). However, the effects of sea cucumbers on CDOM are still unknown. During more than one year, we monitored CDOM in two big-volume tanks with different trophic structure. One of the tanks (-holothurian) only contained around 810 individuals of Anemonia sulcata , whereas the other tank (+holothurian) also included 90 individuals of Holothuria tubulosa and Holothuria forskali . We routinely analyzed CDOM absorption spectra and determined quantitative (absorption coefficients at 325 nm) and qualitative (spectral slopes) optical parameters in the inlet waters, within the tanks, and in their corresponding effluents. To confirm the time-series results, we also performed three experiments. Each experiment consisted of two treatments: +holothurians (+H) and -holothurians (-H). We set up three +H tanks with 80 individuals of A. sulcata and 10 individuals of H. tubulosa in each tank and four -H tanks that contained only 80 individuals of A. sulcata . In the time-series, absorption coefficients at 325 nm ( a 325 ) and spectral slopes from 275 to 295 nm ( S 275-295 ) were significantly lower in the effluent of the +holothurian tank (average: 0.33 m -1 and 16 µm -1 , respectively) than in the effluent of the -holothurian tank (average: 0.69 m -1 and 34 µm -1 , respectively), the former being similar to those found in the inlet

  19. Predicting salt advection in groundwater from saline aquaculture ponds

    Science.gov (United States)

    Verrall, D. P.; Read, W. W.; Narayan, K. A.

    2009-01-01

    SummaryThis paper predicts saltwater advection in groundwater from leaky aquaculture ponds. A closed form solution for the potential function, stream function and velocity field is derived via the series solutions method. Numerically integrating along different streamlines gives the location (or advection front) of saltwater throughout the domain for any predefined upper time limit. Extending this process produces a function which predicts advection front location against time. The models considered in this paper are easily modified given knowledge of the required physical parameters.

  20. Impact of an aquaculture extension project in Bangladesh

    DEFF Research Database (Denmark)

    Rand, John; Tarp, Finn

    2009-01-01

    productivity and the value of fish production per capita among participants. However, in the long run no similar well-determined effect emerges. Second, MAEP appears to have had no significant impact on socioeconomic status as measured by consumption expenditure of participating households. The authors argue......This paper is an impact study of key short- and long-run effects of the Danida supported Mymensingh Aquaculture Extension Project (MAEP) in Bangladesh, applying different matching and double difference estimators. Results are mixed. First, the paper finds a positive short-run impact on pond...

  1. The Greenhouse and Anti-Greenhouse Effects on Titan

    Science.gov (United States)

    McKay, C. P.; Cuzzi, Jeffrey N. (Technical Monitor)

    1994-01-01

    Titan is the largest moon of Saturn and is the only moon in the solar system with a substantial atmosphere. Its atmosphere is mostly made of nitrogen, with a few percent CH4, 0.1% H2 and an uncertain level of Ar (less than 10%). The surface pressure is 1.5 atms and the surface temperature is 95 K, decreasing to 71 at the tropopause before rising to stratospheric temperatures of 180 K. In pressure and composition Titan's atmosphere is the closest twin to Earth's. The surface of Titan remains unknown, hidden by the thick smog layer, but it may be an ocean of liquid methane and ethane. Titan's atmosphere has a greenhouse effect which is much stronger than the Earth's - 92% of the surface warming is due to greenhouse radiation. However an organic smog layer in the upper atmosphere produces an anti-greenhouse effect that cuts the greenhouse warming in half - removing 35% of the incoming solar radiation. Models suggest that during its formation Titan's atmosphere was heated to high temperatures due to accretional energy. This was followed by a cold Triton-like period which gradually warmed to the present conditions. The coupled greenhouse and haze anti-greenhouse may be relevant to recent suggestions for haze shielding of a CH4 - NH3 early atmosphere on Earth or Mars. When the NASA/ESA mission to the Saturn System, Cassini, launches in a few years it will carry a probe that will be sent to the surface of Titan and show us this world that is strange and yet in many ways similar to our own.

  2. 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...

  3. 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 ...

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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...

  9. 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

  10. 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

  11. 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

  12. 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

  13. Assessing stakeholder's experience and sensitivity on key issues for the economic growth of organic aquaculture production

    DEFF Research Database (Denmark)

    Lembo, Giuseppe; Jokumsen, Alfred; Spedicato, Maria Teresa

    2018-01-01

    expressed by the participants revealed both competence and awareness, despite the complexity of the subject. Several ideas and useful suggestions emerged regarding unresolved technical issues. In addition, the need for a targeted communication strategy on the quality of organic aquaculture products...... and the necessity of fostering European/national programs to support the production and marketing of organic aquaculture products were highlighted...

  14. 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 ...

  15. 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

  16. 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.

  17. 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 ...

  18. 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).

  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. Feasibility of biodiesel production and CO2 emission reduction by Monoraphidium dybowskii LB50 under semi-continuous culture with open raceway ponds in the desert area.

    Science.gov (United States)

    Yang, Haijian; He, Qiaoning; Hu, Chunxiang

    2018-01-01

    Compared with other general energy crops, microalgae are more compatible with desert conditions. In addition, microalgae cultivated in desert regions can be used to develop biodiesel. Therefore, screening oil-rich microalgae, and researching the algae growth, CO 2 fixation and oil yield in desert areas not only effectively utilize the idle desertification lands and other resources, but also reduce CO 2 emission. Monoraphidium dybowskii LB50 can be efficiently cultured in the desert area using light resources, and lipid yield can be effectively improved using two-stage induction and semi-continuous culture modes in open raceway ponds (ORPs). Lipid content (LC) and lipid productivity (LP) were increased by 20% under two-stage industrial salt induction, whereas biomass productivity (BP) increased by 80% to enhance LP under semi-continuous mode in 5 m 2 ORPs. After 3 years of operation, M. dybowskii LB50 was successfully and stably cultivated under semi-continuous mode for a month during five cycles of repeated culture in a 200 m 2 ORP in the desert area. This culture mode reduced the supply of the original species. The BP and CO 2 fixation rate were maintained at 18 and 33 g m -2  day -1 , respectively. Moreover, LC decreased only during the fifth cycle of repeated culture. Evaporation occurred at 0.9-1.8 L m -2  day -1 , which corresponded to 6.5-13% of evaporation loss rate. Semi-continuous and two-stage salt induction culture modes can reduce energy consumption and increase energy balance through the energy consumption analysis of life cycle. This study demonstrates the feasibility of combining biodiesel production and CO 2 fixation using microalgae grown as feedstock under culture modes with ORPs by using the resources in the desert area. The understanding of evaporation loss and the sustainability of semi-continuous culture render this approach practically viable. The novel strategy may be a promising alternative to existing technology for CO 2 emission

  1. 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...

  2. Control methodologies based on geothermal recirculating aquaculture system

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  3. Mooring Design Selection of Aquaculture Cage for Indonesian Ocean

    Science.gov (United States)

    Mulyadi, Y.; Syahroni, N.; Sambodho, K.; Zikra, M.; Wahyudi; Adia, H. B. P.

    2018-03-01

    Fish production is important for the economy in fishing community and for ensuring food security. Climate change will lead a threat to fish productivity. Therefore, a solution offered is to cultivate certain fish, especially those with high economic value by using offshore aquaculture technology. A Sea Station cage is one of the offshore aquaculture cage model that has been used in some locations. As a floating structure, the Sea Station cage need a mooring system to maintain its position. This paper presents the selection analysis of the mooring system designs of the Sea Station cage model that it is suitable with Indonesia Ocean. There are 3 mooring configurations that are linear array, rectangular array, and 4 points mooring type. The nylon mooring rope type has been selected to be used on the 3 mooring configurations and the rope has a diameter of 104 mm with a breaking force of 2.3 MN. Based on results from comparing the 3 mooring configurations, the best mooring configuration is linear array with the tension on the rope of 217 KN and has the safety factor of 0.2 based on DNVGL OS-E301

  4. Applications of Microalgal Biotechnology for Disease Control in Aquaculture

    Directory of Open Access Journals (Sweden)

    Patai Charoonnart

    2018-04-01

    Full Text Available Aquaculture industries, and in particular the farming of fish and crustaceans, are major contributors to the economy of many countries and an increasingly important component in global food supply. However, the severe impact of aquatic microbial diseases on production performance remains a challenge to these industries. This article considers the potential applications of microalgal technology in the control of such diseases. At the simplest level, microalgae offer health-promoting benefits as a nutritional supplement in feed meal because of their digestibility and high content of proteins, lipids and essential nutrients. Furthermore, some microalgal species possess natural anti-microbial compounds or contain biomolecules that can serve as immunostimulants. In addition, emerging genetic engineering technologies in microalgae offer the possibility of producing ‘functional feed additives’ in which novel and specific bioactives, such as fish growth hormones, anti-bacterials, subunit vaccines, and virus-targeted interfering RNAs, are components of the algal supplement. The evaluation of such technologies for farm applications is an important step in the future development of sustainable aquaculture.

  5. NALYSIS OF ROMANIAN FISHERIES AND AQUACULTURE IN REGIONAL CONTEXT

    Directory of Open Access Journals (Sweden)

    Mihaela\tNECULITA

    2015-06-01

    Full Text Available Integration in European Union assumes obtaining certain benefits. Fisheries and aquaculture can provide a key contribution to food security and poverty alleviation. Employment in the sector has grown faster than the world’s population, providing jobs and supports the livelihoods of hundreds of millions. Fish continues to be one of the most- traded food commodities worldwide being very important for developing countries. However, productivity gains in fisheries do not always imply long-term increases in supply. Developing countries are continuing their efforts to clarify the linkage between development activities and sustainable resource use. Both population and economic growth are putting enormous additional pressures on inland and marine fisheries resources as contributors to food security and providers of a social safety net. At the same time, the use of domestic fisheries to generate foreign exchange is exacerbating allocation issues between artisan and industrial fleets. The actual fisheries legislation was influence by social, economic and environmental considerations. The paper proposes an integrated analysis of Romanian situation by means of data and statistics provided by European and national statistics institutions. Fisheries in general and aquaculture sector in particular could be regarded as an advantage for Romania in the European competition. The main problem of the Romanian fisheries is its unsatisfactory competitiveness both regarding the domestic and European market.

  6. Exploring fish microbial communities to mitigate emerging diseases in aquaculture.

    Science.gov (United States)

    de Bruijn, Irene; Liu, Yiying; Wiegertjes, Geert F; Raaijmakers, Jos M

    2018-01-01

    Aquaculture is the fastest growing animal food sector worldwide and expected to further increase to feed the growing human population. However, existing and (re-)emerging diseases are hampering fish and shellfish cultivation and yield. For many diseases, vaccination protocols are not in place and the excessive use of antibiotics and other chemicals is of substantial concern. A more sustainable disease control strategy to protect fish and shellfish from (re-)emerging diseases could be achieved by introduction or augmentation of beneficial microbes. To establish and maintain a 'healthy' fish microbiome, a fundamental understanding of the diversity and temporal-spatial dynamics of fish-associated microbial communities and their impact on growth and health of their aquatic hosts is required. This review describes insights in the diversity and functions of the fish bacterial communities elucidated with next-generation sequencing and discusses the potential of the microbes to mitigate (re-)emerging diseases in aquaculture. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. PROBLEMS OF BIOFOULING ON FISH–CAGE NETS IN AQUACULTURE

    Directory of Open Access Journals (Sweden)

    Merica Slišković

    2002-09-01

    Full Text Available Biofouling on fish–cage netting is a serious technical and economical problem to aquaculture worldwide. Compensation for the effects of biofouling must be included in cage system design and planning, as fouling can dramatically increase both weight and drag. Settlements of sessile plants and animals, with accumulation of the detritus diminish the size of mesh and can rapidly occlude mesh. Negative effect of smaller mesh size is changing in water flow trough the cages. Biofouling problems necessitating purchase of a second sets of nets or more, and frequent cleaning and changing of biofouling. Changing and cleaning frequency depend on many factors such as: location of cages (near the coast or off shore, productivity of that location, time of the year, time period in which the cages are placed on that location (cause of loading of phosphorus and nitrogen from the unconsumed food in the sediment. Net changing and cleaning procedures are labor and capital intensive. Process of the cleaning of the nets is inadequate, especially when there isnžt adequate equipment available as it is case in smaller aquaculture industry. Chemical control of biofouling e. g. use of antifoulants is questioningly cause of their possible negative effects on breeding species and environment.

  8. 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.

  9. Sourcebook on the greenhouse effect

    International Nuclear Information System (INIS)

    Ellis, E.; Devine, J.

    1990-01-01

    The Greenhouse Effect Sourcebook contains information for anyone interested in the environment and the present changes which are taking place. It can be used to trace organisations, technical literature or reports. Much of the information relates to the environment in general. The sourcebook contains:- A list of Greenhouse Effect Information useful sources of information under a variety of headings:-Abstracts and indexes, books, conferences, directories, journals, official publications, online databases, (produces and hosts) and organisations, -The Greenhouse Effect References contains over 250 abstracts and details of recently published material, on a variety of environmental subjects from acid rain and aerosols to weather forecasting and wildlife. There is an author index for the references and a keyword index. (author)

  10. 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.

  11. Greenhouse effect: analysis, incertitudes, consequences

    International Nuclear Information System (INIS)

    Perrier, A.

    1991-01-01

    A general presentation of climatic changes due to greenhouse effect with their consequences is analysed. After a schematic description of this effect a simplified atmospheric model (box model) is proposed. This model integrates the main feedback effects and quantifies them. The effects of astronomic and atmospheric factors on climatic changes are analyzed and compared with classical paleoclimatic results. This study shows the need of good global modelization to evaluate long term quantification of climatic greenhouse effects according to the main time lag of the several biospheric boxes. An overview of biologic and agronomic consequences is given to promote new research subjects and to orientate protecting and conservative biospheric actions [fr

  12. Effect of drainage on CO2, CH4, and N2O fluxes from aquaculture ponds during winter in a subtropical estuary of China.

    Science.gov (United States)

    Yang, Ping; Lai, Derrick Y F; Huang, Jia F; Tong, Chuan

    2018-03-01

    Aquaculture ponds are dominant features of the landscape in the coastal zone of China. Generally, aquaculture ponds are drained during the non-culture period in winter. However, the effects of such drainage on the production and flux of greenhouse gases (GHGs) from aquaculture ponds are largely unknown. In the present study, field-based research was performed to compare the GHG fluxes between one drained pond (DP, with a water depth of 0.05m) and one undrained pond (UDP, with a water depth of 1.16m) during one winter in the Min River estuary of southeast China. Over the entire study period, the mean CO 2 flux in the DP was (0.75±0.12) mmol/(m 2 ·hr), which was significantly higher than that in the UDP of (-0.49±0.09) mmol/(m 2 ·hr) (paquaculture ponds from a net sink to a net source of CO 2 in winter. Mean CH 4 and N 2 O emissions were significantly higher in the DP compared to those in the UDP (CH 4 =(0.66±0.31) vs. (0.07±0.06) mmol/(m 2 ·hr) and N 2 O=(19.54±2.08) vs. (0.01±0.04) µmol/(m 2 ·hr)) (paquaculture ponds can increase the emissions of potent GHGs from the coastal zone of China to the atmosphere during winter, further aggravating the problem of global warming. Copyright © 2017. Published by Elsevier B.V.

  13. 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.

  14. Steps toward a cooler greenhouse

    International Nuclear Information System (INIS)

    Kerr, R.A.

    1991-01-01

    In April a committee of the National Academies of Science and Engineering and the Institute of Medicine urged the Bush Administration and Congress to begin cutting emissions of greenhouse gases immediately. The risk of delay is great, and the cost of insurance against disastrous climate warming is cheap. Now the committee's panel on mitigation has issued a 500-page report describing just how cheap that hedge against a climate calamity could be. The panel found that it would not be unreasonable to expect that a 25% reduction in US greenhouse gas emissions might be achieved at a cost of less than $10 per ton of carbon dioxide or its equivalent in other greenhouse gases. In more familiar terms, that considerable reduction in greenhouse emissions would cost about $4.75 for each barrel of oil burned or $0.11 per gallon of gasoline. The most cost-effective measures for reducing emissions, are increasing the energy efficiency of residential and commercial buildings and activities, vehicles, and industrial processes that use electricity

  15. Irrigation management in organic greenhouse

    NARCIS (Netherlands)

    Voogt, W.; Balendonck, J.; Berkelmans, R.; Enthoven, N.

    2017-01-01

    Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus

  16. The Living Rainforest Sustainable Greenhouses

    NARCIS (Netherlands)

    Bot, G.P.A.; Zwart, de H.F.; Hansen, K.; Logan, A.; Witte Groenholland, H.

    2008-01-01

    The Living Rainforest (www.livingrainforest.org) is an educational charity that uses rainforest ecology as a metaphor for communicating general sustainability issues to the public. Its greenhouses and office buildings are to be renovated using the most sustainable methods currently available. This

  17. A need for greenhouse geology

    Energy Technology Data Exchange (ETDEWEB)

    Vermaak, F

    1991-12-01

    As regards the greenhouse issue, research has reached the frontiers of present-day scientific knowledge and understanding. Earth scientists, especially geologists could provide extra input, for example from studies of the sun's energy activity; by providing data on CO{sub 2} storage in the oceans and coral reefs; and on the climatic effect of volcanic activity.

  18. The Peculiar Negative Greenhouse Effect Over Antarctica

    Science.gov (United States)

    Sejas, S.; Taylor, P. C.; Cai, M.

    2017-12-01

    Greenhouse gases warm the climate system by reducing the energy loss to space through the greenhouse effect. Thus, a common way to measure the strength of the greenhouse effect is by taking the difference between the surface longwave (LW) emission and the outgoing LW radiation. Based on this definition, a paradoxical negative greenhouse effect is found over the Antarctic Plateau, which suprisingly indicates that greenhouse gases enhance energy loss to space. Using 13 years of NASA satellite observations, we verify the existence of the negative greenhouse effect and find that the magnitude and sign of the greenhouse effect varies seasonally and spectrally. A previous explanation attributes the negative greenhouse effect solely to stratospheric CO2 and warmer than surface stratospheric temperatures. However, we surprisingly find that the negative greenhouse effect is predominantly caused by tropospheric water vapor. A novel principle-based explanation provides the first complete account of the Antarctic Plateau's negative greenhouse effect indicating that it is controlled by the vertical variation of temperature and greenhouse gas absorption strength. Our findings indicate that the strong surface-based temperature inversion and scarcity of free tropospheric water vapor over the Antarctic Plateau cause the negative greenhouse effect. These are climatological features uniquely found in the Antarctic Plateau region, explaining why the greenhouse effect is positive everywhere else.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Accounting for Greenhouse Gas Emissions from Reservoirs

    Science.gov (United States)

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes ...

  4. Building and using the solar greenhouse

    Energy Technology Data Exchange (ETDEWEB)

    None

    1983-01-01

    Thorough directions are given for planning, constructing and using a solar greenhouse attached to a house. Included is a method of calculating the savings accruing from the use of the greenhouse. (LEW)

  5. The Greenhouse Effect: Science and Policy.

    Science.gov (United States)

    Schneider, Stephen H.

    1989-01-01

    Discusses many of the scientific questions surrounding the greenhouse effect debate and the issue of plausible responses. Discussion includes topics concerning projecting emissions and greenhouse gas concentrations, estimating global climatic response, economic, social, and political impacts, and policy responses. (RT)

  6. 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.

  7. Exergetic performance analysis of a recirculating aquaculture system

    International Nuclear Information System (INIS)

    Kucuk, Haydar; Midilli, Adnan; Ozdemir, Atilla; Cakmak, Eyuep; Dincer, Ibrahim

    2010-01-01

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

  8. Particle surface area and bacterial activity in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Pedersen, Per Bovbjerg; von Ahnen, Mathis; Fernandes, Paulo

    2017-01-01

    Suspended particles in recirculating aquaculture systems (RAS) provide surface area that can be colonized by bacteria. More particles accumulate as the intensity of recirculation increases thus potentially increasing the bacterial carrying capacity of the systems. Applying a recent, rapid, culture...... but may provide significant surface area. Hence, the study substantiates that particles in RAS provide surface area supporting bacterial activity, and that particles play a key role in controlling the bacterial carrying capacity at least in less intensive RAS. Applying fast, culture-independent techniques......-independent fluorometric detection method (Bactiquant®) for measuring bacterial activity, the current study explored the relationship between total particle surface area (TSA, derived from the size distribution of particles >5 μm) and bacterial activity in freshwater RAS operated at increasing intensity of recirculation...

  9. Aquaculture and the utilisation of plant wastes in fish feeds

    CSIR Research Space (South Africa)

    Jacobs, A

    2010-08-31

    Full Text Available shape and size of pellets vary between species and age of the fish • Feed management needs on fish farms, must be convenient, thus feed must be stable, dry, easy to handle, cost-effective © CSIR 2010 Slide 5 Plant-based feedstuffs to replace... Acids 65.4 0.77 1.4 0.7 18.3 0.8 1.5 0.7 Fermented Soya 56.1 0.68 1.7 0.6 18.4 0.8 1.6 0.6 © CSIR 2010 Slide 16 The effect of aquaculture biological agents on water quality during feeding trials • Freshwater finfish Oreochromis...

  10. Role and functions of beneficial microorganisms in sustainable aquaculture.

    Science.gov (United States)

    Zhou, Qunlan; Li, Kangmin; Jun, Xie; Bo, Liu

    2009-08-01

    This paper aims to review the development of scientific concepts of microecology and ecology of microbes and the role and functions of beneficial microorganisms in aquaculture and mariculture. Beneficial microorganisms play a great role in natural and man-made aquatic ecosystems based on the co-evolution theory in living biosphere on earth. Their functions are to adjust algal population in water bodies so as to avoid unwanted algal bloom; to speed up decomposition of organic matter and to reduce CODmn, NH3-N and NO2-N in water and sediments so as to improve water quality; to suppress fish/shrimp diseases and water-borne pathogens; to enhance immune system of cultured aquatic animals and to produce bioactive compounds such as vitamins, hormones and enzymes that stimulate growth, thus to decrease the FCR of feed.

  11. Infectious diseases in oyster aquaculture require a new integrated approach.

    Science.gov (United States)

    Pernet, Fabrice; Lupo, Coralie; Bacher, Cédric; Whittington, Richard J

    2016-03-05

    Emerging diseases pose a recurrent threat to bivalve aquaculture. Recently, massive mortality events in the Pacific oyster Crassostrea gigas associated with the detection of a microvariant of the ostreid herpesvirus 1 (OsHV-1µVar) have been reported in Europe, Australia and New Zealand. Although the spread of disease is often viewed as a governance failure, we suggest that the development of protective measures for bivalve farming is presently held back by the lack of key scientific knowledge. In this paper, we explore the case for an integrated approach to study the management of bivalve disease, using OsHV-1 as a case study. Reconsidering the key issues by incorporating multidisciplinary science could provide a holistic understanding of OsHV-1 and increase the benefit of research to policymakers. © 2016 The Author(s).

  12. Biofloc technology application in aquaculture to support sustainable development goals.

    Science.gov (United States)

    Bossier, Peter; Ekasari, Julie

    2017-09-01

    Biofloc technology (BFT) application offers benefits in improving aquaculture production that could contribute to the achievement of sustainable development goals. This technology could result in higher productivity with less impact to the environment. Furthermore, biofloc systems may be developed and performed in integration with other food production, thus promoting productive integrated systems, aiming at producing more food and feed from the same area of land with fewer input. The biofloc technology is still in its infant stage. A lot more research is needed to optimise the system (in relation to operational parameters) e.g. in relation to nutrient recycling, MAMP production, immunological effects. In addition research findings will need to be communicated to farmers as the implementation of biofloc technology will require upgrading their skills. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  13. Sea cucumbers reduce chromophoric dissolved organic matter in aquaculture tanks

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Sadeghi-Nassaj

    2018-02-01

    Full Text Available Background Mono-specific aquaculture effluents contain high concentrations of nutrients and organic matter, which affect negatively the water quality of the recipient ecosystems. A fundamental feature of water quality is its transparency. The fraction of dissolved organic matter that absorbs light is named chromophoric dissolved organic matter (CDOM. A sustainable alternative to mono-specific aquaculture is the multitrophic aquaculture that includes species trophically complementary named “extractive” species that uptake the waste byproducts. Sea cucumbers are recognized as efficient extractive species due to the consumption of particulate organic matter (POM. However, the effects of sea cucumbers on CDOM are still unknown. Methods During more than one year, we monitored CDOM in two big-volume tanks with different trophic structure. One of the tanks (−holothurian only contained around 810 individuals of Anemonia sulcata, whereas the other tank (+holothurian also included 90 individuals of Holothuria tubulosa and Holothuria forskali. We routinely analyzed CDOM absorption spectra and determined quantitative (absorption coefficients at 325 nm and qualitative (spectral slopes optical parameters in the inlet waters, within the tanks, and in their corresponding effluents. To confirm the time-series results, we also performed three experiments. Each experiment consisted of two treatments: +holothurians (+H and –holothurians (−H. We set up three +H tanks with 80 individuals of A. sulcata and 10 individuals of H. tubulosa in each tank and four –H tanks that contained only 80 individuals of A. sulcata. Results In the time-series, absorption coefficients at 325 nm (a325 and spectral slopes from 275 to 295 nm (S275−295 were significantly lower in the effluent of the +holothurian tank (average: 0.33 m−1 and 16 µm−1, respectively than in the effluent of the −holothurian tank (average: 0.69 m−1 and 34 µm−1, respectively, the former

  14. Shrimp aquaculture in low salinity water feeded with worm flavor

    Directory of Open Access Journals (Sweden)

    Wenceslao Valenzuela Quiñónez

    2012-09-01

    Full Text Available Shrimp aquaculture in Sinaloa is one of the top economic enterprises, generating many jobs and earns significant incomes every year. Shrimp feed is an essential part of maintaining healthy production. In this initial approach of shrimp growth in low salinity water, were tested two formulas of animal protein composed of 40% (APL1 and 20% (APL2 worm protein, a commercial diet, and no supplementary feed. Physicochemical parameters did not have a direct influence in shrimpbehavior. After six weeks of experimentation, shrimp fed with commercial diet had a weight gain 20% higher than those feed with worm protein. There were no significantly differences between sizes with respect to 40% animal protein and 20% animal protein with the commercial diet (P  0.05. However, shrimp fed worm protein had lower mortality. The use of worm protein could be an option to maintain a high quantity of shrimp reared in low salinity waters.

  15. Greenhouse gas emissions increase global warming

    OpenAIRE

    Mohajan, Haradhan

    2011-01-01

    This paper discusses the greenhouse gas emissions which cause the global warming in the atmosphere. In the 20th century global climate change becomes more sever which is due to greenhouse gas emissions. According to International Energy Agency data, the USA and China are approximately tied and leading global emitters of greenhouse gas emissions. Together they emit approximately 40% of global CO2 emissions, and about 35% of total greenhouse gases. The developed and developing industrialized co...

  16. Prevention of zebra mussel infestation and dispersal during aquaculture operations

    Science.gov (United States)

    Waller, D.L.; Fisher, S.W.; Dabrowska, H.

    1996-01-01

    The zebra mussel Dreissena polymorpha, an exotic invasive species, poses a major threat to North American fish management programs and the aquaculture industry. Fish hatcheries may become infected with zebra mussels from a variety of sources, including the water supply, fish shipments, boats, and equipment. The hatcheries could then serve as agents for the overland dispersal of zebra mussels into stocked waters and to other fish hatcheries. We evaluated the effectiveness and safety of aquaculture chemicals for use in controlling zebra mussels in fish hatcheries and preventing dispersal of veligers during fish transport. Chemicals were evaluated for use in fish transport and as disinfectants for ponds and equipment. Standardized static toxicity tests were conducted with representative species of warmwater, coolwater, and coldwater fishes and with larval (3-d-old veligers), early juvenile (settling larvae), and adult zebra mussels. Chemical concentrations and exposure durations were based on recommended treatment levels for fish, eggs, and ponds. Recommended treatment levels were also exceeded, if necessary, to establish lethal levels for zebra mussels of different developmental stages. Our results indicate that some chemicals currently in use in hatcheries may be effective for controlling zebra mussels in various operations. Chloride salts were the safest and most effective therapeutants tested for use in fish transport. The toxicity of chloride salts to fish varied among species and with temperature; only one treatment regime (sodium chloride at 10,000 mg/L) was safe to all fish species that we tested, but it was only effective on veliger and settler stages of the zebra mussel. Effective disinfectants were benzalkonium chloride for use on equipment and rotenone for use in ponds after fish are harvested. The regulatory status of the identified chemicals is discussed as well as several nonchemical control alternatives.

  17. 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....

  18. Optimal Control Design for a Solar Greenhouse

    NARCIS (Netherlands)

    Ooteghem, van R.J.C.

    2010-01-01

    Abstract: An optimal climate control has been designed for a solar greenhouse to achieve optimal crop production with sustainable instead of fossil energy. The solar greenhouse extends a conventional greenhouse with an improved roof cover, ventilation with heat recovery, a heat pump, a heat

  19. Optimal control design for a solar greenhouse

    NARCIS (Netherlands)

    Ooteghem, van R.J.C.

    2007-01-01

    The research of this thesis was part of a larger project aiming at the design of a greenhouse and an associated climate control that achieves optimal crop production with sustainable instead of fossil energy. This so called solar greenhouse design extends a conventional greenhouse with an improved

  20. The Greenhouse Effect and Built Environment Education.

    Science.gov (United States)

    Greenall Gough, Annette; Gough, Noel

    The greenhouse effect has always existed. Without the greenhouse effect, Earth could well have the oven-like environment of Venus or the deep-freeze environment of Mars. There is some debate about how much the Earth's surface temperature will rise given a certain amount of increase in the amount of greenhouse gases such as carbon dioxide, nitrous…

  1. A validated physical model of greenhouse climate

    International Nuclear Information System (INIS)

    Bot, G.P.A.

    1989-01-01

    In the greenhouse model the momentaneous environmental crop growth factors are calculated as output, together with the physical behaviour of the crop. The boundary conditions for this model are the outside weather conditions; other inputs are the physical characteristics of the crop, of the greenhouse and of the control system. The greenhouse model is based on the energy, water vapour and CO 2 balances of the crop-greenhouse system. While the emphasis is on the dynamic behaviour of the greenhouse for implementation in continuous optimization, the state variables temperature, water vapour pressure and carbondioxide concentration in the relevant greenhouse parts crop, air, soil and cover are calculated from the balances over these parts. To do this in a proper way, the physical exchange processes between the system parts have to be quantified first. Therefore the greenhouse model is constructed from submodels describing these processes: a. Radiation transmission model for the modification of the outside to the inside global radiation. b. Ventilation model to describe the ventilation exchange between greenhouse and outside air. c. The description of the exchange of energy and mass between the crop and the greenhouse air. d. Calculation of the thermal radiation exchange between the various greenhouse parts. e. Quantification of the convective exchange processes between the greenhouse air and respectively the cover, the heating pipes and the soil surface and between the cover and the outside air. f. Determination of the heat conduction in the soil. The various submodels are validated first and then the complete greenhouse model is verified

  2. Crossing the chasm in Dutch greenhouse horticulture

    NARCIS (Netherlands)

    Buurma, J.S.; Smit, P.X.

    2016-01-01

    Dutch greenhouse horticulture has an innovation and development programme called 'Kas als Energiebron' (Greenhouse as Energy Producer). The objective of this programme is reducing the carbon footprint and improving the energy efficiency of greenhouse horticulture, and developing a climate neutral

  3. Using waste oil to heat a greenhouse

    Science.gov (United States)

    Marla Schwartz

    2009-01-01

    During the winter of 1990, Northwoods Nursery (Elk River, ID) purchased a wood-burning system to heat the current greenhouses. This system burned slabs of wood to heat water that was then pumped into the greenhouses. The winter of 1990 was extremely harsh, requiring non-stop operation of the heating system. In order to keep seedlings in the greenhouse from freezing,...

  4. 75 FR 57669 - Mandatory Reporting of Greenhouse Gases

    Science.gov (United States)

    2010-09-22

    ... Mandatory Reporting of Greenhouse Gases AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action amends the Final Mandatory Reporting of Greenhouse Gases Rule to require reporters... Numbers GHG greenhouse gas GHGRP Greenhouse Gas Reporting Program HCFC hydrochlorofluorocarbon HFC...

  5. Organic fertigation for greenhouse crops

    DEFF Research Database (Denmark)

    Pokhrel, Bhaniswor

    2017-01-01

    productivity is suboptimal nutrient management resulting from poor synchronization between crop nutrient demand and nutrient release from organic fertilizers, affecting the physical, chemical and biological characteristics of the root zone environment, and thus plant growth and productivity. Compared to solid...... organic fertilizers, the application of liquid organic fertilizers potentially more accurately addresses the nutrient demand, because nutrients are readily available and different fertilizers are easily mixed. This PhD work explores the possibilities and challenges related to the application of liquid...... organic fertilizers in organic greenhouse crop production. Four greenhouse experiments were designed where different liquid organic fertilizers were prepared: acidic extraction or anaerobic digestion of red clover and white mustard silage, water extraction of composted chicken manure and flushing...

  6. AVALIAÇÃO ECONÔMICA DA PRODUÇÃO DA TILÁPIA-DO-NILO EM TANQUES COM DIFERENTES ESQUEMAS DE TROCA DE ÁGUA NO SISTEMA RACEWAY

    Directory of Open Access Journals (Sweden)

    Raquel Priscila de Castro Oliveira

    2010-12-01

    Full Text Available This study was carried out to evaluate the production costs and gross revenue per Nile tilapia (Oreochromis niloticus productionarea unit, in raceway system, in tanks submitted to different water exchange projects, based on ration and fingerlings costs. Nile tilapia fingerlings, reverted to males, were used. They were fed three times a day, ad libitum, with extruded commercial ration. The following economic analyses were carried out: cost incidence, partial net revenue, gross revenue and partial operational cost. The best biomass result found induced the greatest partial net revenue, observed in the treatment in which the highest water exchange (30 minutes was used. In this treatment, the tanks with 500 L (0.5 m3 of water provided a partial net revenue average of R$ 50.77 equivalent to R$ 101.54/m3, in the period of 120 days.

  7. Greenhouse effects of aircraft emissions

    International Nuclear Information System (INIS)

    Fortuin, J.P.F.; Wauben, W.M.F.; Dorland, R. van; Kelder, H.

    1996-01-01

    Ranges for direct and indirect greenhouse effects due to present day aircraft emissions are quantified for northern midlatitudes, using the concept of fixed temperature (FT) radiative forcing as calculated with a radiative transfer model. The direct greenhouse effects considered here are from emissions of carbon dioxide, water vapor, and nitrogen dioxide. To calculate the concentration increases of carbon dioxide and stratospheric water vapor, an analytical expression is developed based on a linear approximation of global fuel burn versus time. Unlike the expressions currently used in the literature, the authors' expression does not account for emission rates only, but also for a loss term--hence making it more suitable for shorter lived emittants. For midlatitude summer conditions, a total radiative forcing ranging from 0.04 to 0.09 Wm -2 is calculated for the direct greenhouse effects, whereas for midlatitude winter the range is 0.07 to 0.26 Wm -2 . The indirect greenhouse effects considered here are sulfate aerosol formation from sulfur dioxide emissions, contrail formation from emitted water vapor and condensation nuclei, and ozone formation from NO x emissions. The total radiative forcing coming from these indirect effects range from -0.67 to 0.25 Wm -2 in summer a/nd from -0.36 to 0.21 Wm -2 in winter. Further, the global distribution of NO x and ozone increases from aircraft emissions world-wide are simulated with a three-dimensional chemistry transport model for January and July. The geographical distribution of the radiative forcing associated with the simulated ozone increases is also calculated for these months

  8. Greenhouse effect: doubts and unknowns

    International Nuclear Information System (INIS)

    Tabarelli, D.

    1992-01-01

    There are few doubts today in the scientific world that atmospheric carbon dioxide traps in heat and therefore contributes to global warming; however, it is yet uncertain as to whether the presence of this gas in the upper atmosphere is the only cause of the greenhouse effect, and the scientific theories defining the effect and its causes present a few obvious and significant gaps. This paper cites the fact that most greenhouse effect models only marginally, if at all, consider the mechanisms governing the formation and absorption of carbon dioxide by the earth's oceans; yet oceanic CO 2 concentration levels are about 60 times greater than those found in the atmosphere, and they depend on complex interactions, in seawater, among such factors as currents, carbon oxygenation, and vegetative activity. Another area of weakness in greenhouse effect modelling stems from the complexity and uncertainty introduced by the fact that, in addition to trapping heat, clouds reflect it, thus giving rise to an opposite cooling effect. In addition, it is pointed out that the current models are limited to predicting global and not regional or local effects

  9. A survey for the presence of microcystins in aquaculture ponds in ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-16

    Nov 16, 2009 ... form of blue green algae in an aquaculture pond, they. *Corresponding author. ... passing through the food chain. Fish and other ... Some of these aqua- culture ponds supply their products (harvested fish) directly to spe-.

  10. Recirculating aquaculture production systems : an overview of different components, management, economics and technology

    NARCIS (Netherlands)

    Kals, J.

    2004-01-01

    Report of a literature study on Recirculating aquaculture production systems executed within the MRG ercirculation program. The report gives an overview of different components, management, economics and technology and is made by the Netherlands Institute for Fisheries Research (RIVO).

  11. Evaluation of waste concrete road materials for use in oyster aquaculture.

    Science.gov (United States)

    2013-02-01

    The primary objective of this study was to determine the suitability of recycled concrete : aggregate (RCA) from road projects as bottom conditioning material for on-bottom oyster : aquaculture in the Chesapeake Bay. The testing was designed to (1) e...

  12. Phase II evaluation of waste concrete road materials for use in oyster aquaculture - field test.

    Science.gov (United States)

    2015-02-01

    The overall objective of this study was to determine the suitability of recycled concrete aggregate : (RCA) from road projects as bottom conditioning material for on-bottom oyster aquaculture in the : Chesapeake Bay. During this Phase of the study, t...

  13. Design and operation of nitrifying trickling filters in recirculating aquaculture: a review

    NARCIS (Netherlands)

    Eding, E.H.; Kamstra, A.; Verreth, J.A.J.; Huisman, E.A.; Klapwijk, A.

    2006-01-01

    This review deals with the main mechanisms and parameters affecting design and performance of trickling filters in aquaculture. Relationships between nitrification rates and easily accessible process parameters, like bulk phase concentration of TAN, O2, organic matter (COD), nitrite, temperature,

  14. Dynamic ecological-economic modeling approach for management of shellfish aquaculture

    CSIR Research Space (South Africa)

    Nobre, AM

    2008-02-01

    Full Text Available The objective of this report is to conceptualize ecological and economic interactions in mariculture; to implement a dynamic ecological-economic model in order to: simulate the socio-economics of aquaculture production, simulate its effects...

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  16. Role of Shellfish Aquaculture in the Reduction of Eutrophication in an Urban Estuary

    Science.gov (United States)

    Land-based management has reduced nutrient discharges; however, many coastal waterbodies remain impaired. Oyster “bioextraction” of nutrients and how oyster aquaculture might complement existing management measures in urban estuaries was examined in Long Island Sound, Connecticut...

  17. Use of ozone for sustainable brackishwater industrial aquaculture and management of environment

    Digital Repository Service at National Institute of Oceanography (India)

    Dwivedi, S.N.

    The use of ozones for sustainable brakish water industrial aquaculture and the management of the environment is discussed. In sample survey conducted in the farms, it was seen that oxygen level was not adequate for high production. Replacement...

  18. Water quality management in shrimp aquaculture ponds using remote water quality logging system

    Digital Repository Service at National Institute of Oceanography (India)

    Sreepada, R.A.; Kulkarni, S.; Suryavanshi, U.; Ingole, B.S.; Drensgstig, A.; Braaten, B.

    Currently an institutional co-operation project funded by NORAD is evaluating different environmental management strategies for sustainable aquaculture in India. A brief description of a remote water quality logging system installed in shrimp ponds...

  19. 78 FR 5403 - Fisheries of the Caribbean, Gulf, and South Atlantic; Aquaculture

    Science.gov (United States)

    2013-01-25

    ...'s Web site at http://gulfcouncil.org/fishery_management_plans/aquaculture_management.php . FOR.... The FMP was initiated to provide a comprehensive framework for authorizing and regulating offshore...

  20. 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...

  1. Phase II evaluation of waste concrete road materials for use in oyster aquaculture - field test.

    Science.gov (United States)

    2014-11-01

    The overall objective of this study was to determine the suitability of recycled concrete : aggregate (RCA) from road projects as bottom conditioning material for on-bottom oyster : aquaculture in the Chesapeake Bay. During this Phase of the study, t...

  2. Shellfish Culture at the Milford Laboratory: hatchery production, stock enhancement and aquaculture research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Provide shellfish in support of Milford Lab efforts, external research projects and regional shellfish restoration. Conduct aquaculture experiments aimed at...

  3. Sustainable brackishwater industrial aquaculture and management of environment- use of ozone

    Digital Repository Service at National Institute of Oceanography (India)

    Dwivedi, S.N.

    Surveys conducted in aquaculture farm showed that oxygen level varies between 3 to 5 ml. oxygen per litre. This is not adequate for high production and also cause pollution. However if aeration is replaced with positively charged ozone, oxygen...

  4. Misuse of multiple comparison tests and underuse of contrast procedures in aquaculture publications

    NARCIS (Netherlands)

    Yossa, R.; Verdegem, M.C.J.

    2015-01-01

    In aquaculture research, independent variables are qualitative (with or without a structure), quantitative, or factorial combinations. A qualitative independent variable is a variable that has unquantifiable, nominal variants (levels), which represent different categories such as the fish gender.

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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...

  10. 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...

  11. 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...

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

    OpenAIRE

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche; Mazurie, Joseph; Buck, Bela H.; Dolmer, Per; Fraser, David; Van Nieuwenhove, Kris; O'Beirn, Francis X.; Sanchez-mata, Adoracion; Thorarinsdottir, Gudrun G.; Strand, Oivind

    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 ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–en...

  13. 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...

  14. Greenhouse Module for Space System: A Lunar Greenhouse Design

    Directory of Open Access Journals (Sweden)

    Zeidler Conrad

    2017-02-01

    Full Text Available In the next 10 to 20 years humankind will return to the Moon and/or travel to Mars. It is likely that astronauts will eventually build permanent settlements there, as a base for long-term crew tended research tasks. It is obvious that the crew of such settlements will need food to survive. With current mission architectures the provision of food for longduration missions away from Earth requires a significant number of resupply flights. Furthermore, it would be infeasible to provide the crew with continuous access to fresh produce, specifically crops with high water content such as tomatoes and peppers, on account of their limited shelf life. A greenhouse as an integrated part of a planetary surface base would be one solution to solve this challenge for long-duration missions. Astronauts could grow their own fresh fruit and vegetables in-situ to be more independent from supply from Earth. This paper presents the results of the design project for such a greenhouse, which was carried out by DLR and its partners within the framework of the Micro-Ecological Life Support System Alternative (MELiSSA program. The consortium performed an extensive system analysis followed by a definition of system and subsystem requirements for greenhouse modules. Over 270 requirements were defined in this process. Afterwards the consortium performed an in-depth analysis of illumination strategies, potential growth accommodations and shapes for the external structure. Five different options for the outer shape were investigated, each of them with a set of possible internal configurations. Using the Analytical Hierarchy Process, the different concept options were evaluated and ranked against each other. The design option with the highest ranking was an inflatable outer structure with a rigid inner core, in which the subsystems are mounted. The inflatable shell is wrapped around the core during launch and transit to the lunar surface. The paper provides an overview of the

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Greenhouse Gases and Animal Agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, J. (ed.) [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido (Japan); Young, B.A. (ed.) [The University of Queensland, Gatton, Queensland 4343 (Australia)

    2002-07-01

    Reports from interdisciplinary areas including microbiology, biochemistry, animal nutrition, agricultural engineering and economics are integrated in this proceedings. The major theme of this book is environmental preservation by controlling release of undesirable greenhouse gases to realize the sustainable development of animal agriculture. Technology exists for the effective collection of methane generated from anaerobic fermentation of animal effluent and its use as a biomass energy source. Fossil fuel consumption can be reduced and there can be increased use of locally available energy sources. In addition, promoting environmentally-conscious agriculture which does not rely on the chemical fertilizer can be realized by effective use of animal manure and compost products.

  5. Greenhouse effect: there are solutions

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    A review of solutions that may be undertaken in order to reduce the greenhouse effect gas emissions is presented: clean energy generation through municipal, agricultural and industrial waste processing, reducing energy consumption through public transportation promotion, clean fuel buses and vehicles, or using energy efficient boilers, reduction of carbon dioxide emission from industry through process optimization, waste recycling, energy substitution and conservation, diminution of CO 2 emissions in commercial and residential sectors through space heating and air conditioning retrofitting, lighting substitution. Pollution abatement potentials are evaluated in each case, notably in France

  6. False advertising in the greenhouse?

    Science.gov (United States)

    Banse, K.

    1991-12-01

    Most scientists are convinced of the importance of their own research subjects. Broecker [1991] has deplored the temptation, if not the tendency, to go overboard and exaggerate this importance once funding enters the mind. In particular, he alleges inflated or even false claims by biological (and other) oceanographers regarding the relevance of their research to the "greenhouse effect," caused by the anthropogenic enhancement of the atmospheric CO2 content. He writes [Broecker, 1991, p. 191]: "In my estimation, on any list of subjects requiring intense study with regard to the prediction of the consequences of CO2 buildup in the atmosphere, I would place marine biological cycles near the bottom."

  7. Greenhouse effect: the right questions

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    This paper gives the point of view of the National Council of French engineers and scientists (CNSIF) after the recent publication of a report about the greenhouse effect by the French Academy of Sciences. The CNSIF agrees with the conclusions of this report and gives to non-specialists additional informations about the definition, causes, divergences of opinions about long-term consequences of this effect, and also about the remedial solutions proposed, their delay of efficiency and the socio-economical and political difficulties encountered for their application. (J.S.)

  8. Infectious diseases affect marine fisheries and aquaculture economics

    Science.gov (United States)

    Lafferty, Kevin D.; Harvell, C. Drew; Conrad, Jonathan M.; Friedman, Carolyn S.; Kent, Michael L.; Kuris, Armand M.; Powell, Eric N.; Rondeau, Daniel; Saksida, Sonja M.

    2015-01-01

    Seafood is a growing part of the economy, but its economic value is diminished by marine diseases. Infectious diseases are common in the ocean, and here we tabulate 67 examples that can reduce commercial species' growth and survivorship or decrease seafood quality. These impacts seem most problematic in the stressful and crowded conditions of aquaculture, which increasingly dominates seafood production as wild fishery production plateaus. For instance, marine diseases of farmed oysters, shrimp, abalone, and various fishes, particularly Atlantic salmon, cost billions of dollars each year. In comparison, it is often difficult to accurately estimate disease impacts on wild populations, especially those of pelagic and subtidal species. Farmed species often receive infectious diseases from wild species and can, in turn, export infectious agents to wild species. However, the impact of disease export on wild fisheries is controversial because there are few quantitative data demonstrating that wild species near farms suffer more from infectious diseases than those in other areas. The movement of exotic infectious agents to new areas continues to be the greatest concern.

  9. Use of Geothermal Energy for Aquaculture Purposes - Phase III

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, W C; Smith, K C

    1981-09-01

    This project, financed by the Pacific Northwest Regional Commission (PNRC), was designed to provide information to evaluate the best methods to use for intensive aquaculture of freshwater prawns, Macrobrachium rosenbergii, using geothermal energy. The freshwater prawn is a tropical organism and is native to southeast Asia. Earlier projects at Oregon Institute of Technology have shown the feasibility of culturing this aquatic animal in geothermal water. This phase of the project was designed to investigate intensive culture of this animal as well as the advantages of growing rainbow trout, ornamental tropical fin fish, and mosquito fish, Gambusia affnis, for vector control using geothermal energy. The research data collected on the prawns was obtained from the stocking and sampling of two 0.2- ha (half-acre) ponds constructed as a part of the project. The ponds are equipped with recording monitors for temperature and flow. The geothermal energy used is the geothermal effluent from the Oregon Institute of Technology heating system. This water is of potable quality and ranges in temperature from 50 to 70oC. The geothermal water used in the ponds is controlled at 27oC, ± 2oC, by using thermostats and solenoid valves. A small building next to the ponds contains facilities for hatching larvae prawns and tanks for growing post-larvae prawns. The hatchery facility makes the project self-sustaining. The hatchery was obtained as part of an earlier PNRC project.

  10. Salmon lice – impact on wild salmonids and salmon aquaculture

    Science.gov (United States)

    Torrissen, O; Jones, S; Asche, F; Guttormsen, A; Skilbrei, O T; Nilsen, F; Horsberg, T E; Jackson, D

    2013-01-01

    Salmon lice, Lepeophtheirus salmonis, are naturally occurring parasites of salmon in sea water. Intensive salmon farming provides better conditions for parasite growth and transmission compared with natural conditions, creating problems for both the salmon farming industry and, under certain conditions, wild salmonids. Salmon lice originating from farms negatively impact wild stocks of salmonids, although the extent of the impact is a matter of debate. Estimates from Ireland and Norway indicate an odds ratio of 1.1:1-1.2:1 for sea lice treated Atlantic salmon smolt to survive sea migration compared to untreated smolts. This is considered to have a moderate population regulatory effect. The development of resistance against drugs most commonly used to treat salmon lice is a serious concern for both wild and farmed fish. Several large initiatives have been taken to encourage the development of new strategies, such as vaccines and novel drugs, for the treatment or removal of salmon lice from farmed fish. The newly sequenced salmon louse genome will be an important tool in this work. The use of cleaner fish has emerged as a robust method for controlling salmon lice, and aquaculture production of wrasse is important towards this aim. Salmon lice have large economic consequences for the salmon industry, both as direct costs for the prevention and treatment, but also indirectly through negative public opinion. PMID:23311858

  11. A Layman's Guide to Geothermal Aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Kenan C.

    1981-01-01

    The following paper is designed as an aid to anyone contemplating a venture into commercially raising giant freshwater prawns, Macrobrachium rosenbergii. Oregon Institute of Technology has been actively involved in a research program to determine the feasibility of such a venture and results to date have been very encouraging. This aquaculture research was initiated in 1975 and was developed as an effort to utilize excess energy from the school’s geothermal heating system. Therefore, most of the information gathered here, will apply to flow-through systems which use geothermal water to maintain a suitable environment for the animals. A study of the market potential for freshwater prawns has been conducted and a favorable response received from wholesale distributors in the Pacific Northwest. Not only is a good market available, but distributors have suggested paying from $4.50 to $5.00 per pound for whole prawns in the size category of 16 to 20 tails to the pound, for a constant fresh supply. By maintaining constant temperatures of 27 degrees Celsius (80 degrees Fahrenheit) ± 1 degree Celsius in our research ponds, we have been able to produce this size prawn in 6 to 8 months.

  12. 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

  13. Economic approaches to greenhouse warming

    International Nuclear Information System (INIS)

    Nordhaus, W.D.

    1991-01-01

    Global environmental problems raise a host of major policy questions. They are all scientifically complex and controversial, and no scientific consensus is likely to emerge until irreversible decisions have been made. The costs and benefits of these changes transcend national boundaries, and nations, which cannot appropriate the global costs and benefits of such changes, are unlikely to be able or willing to make efficient decisions on how to combat these global externalities. In addition, these concerns sometimes have impacts over hundreds of years and thereby strain political decision making, which often functions effectively only when the crisis is at hand. This chapter considers some of the economic issues involved in deciding how to react to the threat of global warming. The author first reviews the theory and evidence on the greenhouse effect. He then presents evidence on the impacts of greenhouse warming, the costs of stabilizing climate, and the kinds of adaptations that might be available. In the final section, he reviews the policy initiatives that nations might follow in the near term

  14. Greenhouse Gas Emissions From Cattle

    Directory of Open Access Journals (Sweden)

    Podkówka Zbigniew

    2015-03-01

    Full Text Available Cattle produce greenhouse gases (GHG which lead to changes in the chemical composition of the atmosphere. These gases which cause greenhouse effect include: methane (CH4, nitrous oxide (N2O, nitrogen oxides (NOx, sulphur dioxide (SO2, ammonia (NH3, dust particles and non-methane volatile organic compounds, commonly described as other than methane hydrocarbons. Fermentation processes taking place in the digestive tract produce ‘digestive gases’, distinguished from gases which are emitted during the decomposition of manure. Among these digestive gases methane and non-methane volatile organic compounds are of particular relevance importance. The amount of gases produced by cows can be reduced by choosing to rear animals with an improved genetically based performance. A dairy cow with higher production efficiency, producing milk with higher protein content and at the same time reduced fat content emits less GHG into the environment. Increasing the ratio of feed mixtures in a feed ration also reduces GHG emissions, especially of methane. By selection of dairy cows with higher production efficiency and appropriate nutrition, the farm's expected milk production target can be achieved while at the same time, the size of the herd is reduced, leading to a reduction of GHG emissions.

  15. Greenhouse gases and emissions trading

    International Nuclear Information System (INIS)

    LeBlanc, A.; Dudek, D.J.

    1993-01-01

    Global cooperation is essential in cutting greenhouse-gas emissions, say Alice LeBlanc and Daniel J. Dudek of the Environmental Defense in New York City. The first step, they continue, is agreement among nations on an overall global limit for all greenhouse gases, followed by an allocation of the global limit among nations. The agreements must contain effective reporting and monitoring systems and enforcement provisions, they add. The Framework Convention on Climate Change, signed by most nations of the world in Brazil in 1992, provides the foundation for such an agreement, LeBlanc and Dudek note. open-quotes International emissions trading is a way to lower costs and expand reduction options for the benefit of all,close quotes they contend. Under such an arrangement, an international agency would assign allowances, stated in tons of carbon dioxide. Countries would be free to buy and sell allowances, but no country could exceed, in a given year, the total allowances it holds. By emitting less than its allowed amount, a country would accumulate more allowances, which it could sell. The authors claim such a system would offer benefits to the world economy by saving billions of dollars in pollution-reduction costs while still achieving emission limits established in an international agreement

  16. A Note on Fourier and the Greenhouse Effect

    OpenAIRE

    Postma, Joseph E.

    2015-01-01

    Joseph Fourier's discovery of the greenhouse effect is discussed and is compared to the modern conception of the greenhouse effect. It is confirmed that what Fourier discovered is analogous to the modern concept of the greenhouse effect. However, the modern concept of the greenhouse effect is found to be based on a paradoxical analogy to Fourier's greenhouse work and so either Fourier's greenhouse work, the modern conception of the greenhouse effect, or the modern definition of heat is incorr...

  17. 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

  18. 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

  19. 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.

  20. The coal industry and its greenhouse challenge

    International Nuclear Information System (INIS)

    Armstrong, A.

    1998-01-01

    The Australian coal industry is actively involved in greenhouse gas emission management and abatement issues. An Australian Coal Association (ACA) position paper on greenhouse in November 1989, recommended a number of strategies to minimise the greenhouse effect, including the enhancement of energy utilisation efficiency, improved energy conversion efficiency at coal-fired power stations, expanded use of solar heating, and improved recycling. All of the strategies have been implemented to various degrees. The management and abatement of greenhouse gas emissions within the coal industry has been approached from an individual operational level, and a 'higher' industry level

  1. Observational determination of the greenhouse effect

    Science.gov (United States)

    Raval, A.; Ramanathan, V.

    1989-01-01

    Satellite measurements are used to quantify the atmospheric greenhouse effect, defined here as the infrared radiation energy trapped by atmospheric gases and clouds. The greenhouse effect is found to increase significantly with sea surface temperature. The rate of increase gives compelling evidence for the positive feedback between surface temperature, water vapor and the greenhouse effect; the magnitude of the feedback is consistent with that predicted by climate models. This study demonstrates an effective method for directly monitoring, from space, future changes in the greenhouse effect.

  2. OPIC Greenhouse Gas Emissions Analysis Details

    Data.gov (United States)

    Overseas Private Investment Corporation — Summary project inventory with independent analysis to quantify the greenhouse gas ("GHG") emissions directly attributable to projects to which the Overseas Private...

  3. The greenhouse advantage of natural gas appliances

    International Nuclear Information System (INIS)

    Coombe, N.

    2000-01-01

    The life cycle report prepared recently by Energetics for the AGA, Assessment of Greenhouse Gas Emissions from Natural Gas, demonstrates clearly the greenhouse advantage natural gas has over coal in generating electricity. This study also goes one step further in applying this life cycle approach to the use of space and water heating within the home. The study shows the significant green-house advantage that natural gas appliances have over electric appliances. Findings from other studies also support this claim. The natural gas suppliers are encouraged to take advantage of the marketing opportunity that these studies provide, offering the householders the fuel that will significantly reduce their contribution to greenhouse emission

  4. 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

  5. Development of Antimicrobial Peptide Prediction Tool for Aquaculture Industries.

    Science.gov (United States)

    Gautam, Aditi; Sharma, Asuda; Jaiswal, Sarika; Fatma, Samar; Arora, Vasu; Iquebal, M A; Nandi, S; Sundaray, J K; Jayasankar, P; Rai, Anil; Kumar, Dinesh

    2016-09-01

    Microbial diseases in fish, plant, animal and human are rising constantly; thus, discovery of their antidote is imperative. The use of antibiotic in aquaculture further compounds the problem by development of resistance and consequent consumer health risk by bio-magnification. Antimicrobial peptides (AMPs) have been highly promising as natural alternative to chemical antibiotics. Though AMPs are molecules of innate immune defense of all advance eukaryotic organisms, fish being heavily dependent on their innate immune defense has been a good source of AMPs with much wider applicability. Machine learning-based prediction method using wet laboratory-validated fish AMP can accelerate the AMP discovery using available fish genomic and proteomic data. Earlier AMP prediction servers are based on multi-phyla/species data, and we report here the world's first AMP prediction server in fishes. It is freely accessible at http://webapp.cabgrid.res.in/fishamp/ . A total of 151 AMPs related to fish collected from various databases and published literature were taken for this study. For model development and prediction, N-terminus residues, C-terminus residues and full sequences were considered. Best models were with kernels polynomial-2, linear and radial basis function with accuracy of 97, 99 and 97 %, respectively. We found that performance of support vector machine-based models is superior to artificial neural network. This in silico approach can drastically reduce the time and cost of AMP discovery. This accelerated discovery of lead AMP molecules having potential wider applications in diverse area like fish and human health as substitute of antibiotics, immunomodulator, antitumor, vaccine adjuvant and inactivator, and also for packaged food can be of much importance for industries.

  6. An integrated fish-plankton aquaculture system in brackish water.

    Science.gov (United States)

    Gilles, S; Fargier, L; Lazzaro, X; Baras, E; De Wilde, N; Drakidès, C; Amiel, C; Rispal, B; Blancheton, J-P

    2013-02-01

    Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous fish and phytoplankton. The fish recycle nutrients by consuming live (and dead) algae and provide the inorganic carbon to fuel the growth of live algae. In the meanwhile, algae purify the water and generate the oxygen required by fishes. Such mechanism stabilizes the functioning of an artificially recycling ecosystem, as exemplified by combining the euryhaline tilapia Sarotherodon melanotheron heudelotii and the unicellular alga Chlorella sp. Feed addition in this ecosystem results in faster fish growth but also in an increase in phytoplankton biomass, which must be limited. In the prototype described here, the algal population control is exerted by herbivorous zooplankton growing in a separate pond connected in parallel to the fish-algae ecosystem. The zooplankton production is then consumed by tilapia, particularly by the fry and juveniles, when water is returned to the main circuit. Chlorella sp. and Brachionus plicatilis are two planktonic species that have spontaneously colonized the brackish water of the prototype, which was set-up in Senegal along the Atlantic Ocean shoreline. In our system, water was entirely recycled and only evaporation was compensated (1.5% volume/day). Sediment, which accumulated in the zooplankton pond, was the only trophic cul-de-sac. The system was temporarily destabilized following an accidental rotifer invasion in the main circuit. This caused Chlorella disappearance and replacement by opportunist algae, not consumed by Brachionus. Following the entire consumption of the Brachionus population by tilapias, Chlorella predominated again. Our artificial ecosystem combining S. m. heudelotii, Chlorella and B. plicatilis thus appeared to be resilient. This farming system was operated over one year with a fish productivity of 1.85 kg/m2 per year during the cold season (January to April).

  7. Phylogeny of the Viral Hemorrhagic Septicemia Virus in European Aquaculture.

    Directory of Open Access Journals (Sweden)

    Michael Cieslak

    Full Text Available One of the most valuable aquaculture fish in Europe is the rainbow trout, Oncorhynchus mykiss, but the profitability of trout production is threatened by a highly lethal infectious disease, viral hemorrhagic septicemia (VHS, caused by the VHS virus (VHSV. For the past few decades, the subgenogroup Ia of VHSV has been the main cause of VHS outbreaks in European freshwater-farmed rainbow trout. Little is currently known, however, about the phylogenetic radiation of this Ia lineage into subordinate Ia clades and their subsequent geographical spread routes. We investigated this topic using the largest Ia-isolate dataset ever compiled, comprising 651 complete G gene sequences: 209 GenBank Ia isolates and 442 Ia isolates from this study. The sequences come from 11 European countries and cover the period 1971-2015. Based on this dataset, we documented the extensive spread of the Ia population and the strong mixing of Ia isolates, assumed to be the result of the Europe-wide trout trade. For example, the Ia lineage underwent a radiation into nine Ia clades, most of which are difficult to allocate to a specific geographic distribution. Furthermore, we found indications for two rapid, large-scale population growth events, and identified three polytomies among the Ia clades, both of which possibly indicate a rapid radiation. However, only about 4% of Ia haplotypes (out of 398 occur in more than one European country. This apparently conflicting finding regarding the Europe-wide spread and mixing of Ia isolates can be explained by the high mutation rate of VHSV. Accordingly, the mean period of occurrence of a single Ia haplotype was less than a full year, and we found a substitution rate of up to 7.813 × 10-4 nucleotides per site per year. Finally, we documented significant differences between Germany and Denmark regarding their VHS epidemiology, apparently due to those countries' individual handling of VHS.

  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. 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.

  10. Probiotics as beneficial microbes in aquaculture: an update on their multiple modes of action: a review.

    Science.gov (United States)

    Zorriehzahra, Mohammad Jalil; Delshad, Somayeh Torabi; Adel, Milad; Tiwari, Ruchi; Karthik, K; Dhama, Kuldeep; Lazado, Carlo C

    2016-12-01

    Wide and discriminate use of antibiotics has resulted in serious biological and ecological concerns, especially the emergence of antibiotic resistance. Probiotics, known as beneficial microbes, are being proposed as an effective and eco-friendly alternative to antibiotics. They were first applied in aquaculture species more than three decades ago, but considerable attention had been given only in the early 2000s. Probiotics are defined as live or dead, or even a component of the microorganisms that act under different modes of action in conferring beneficial effects to the host or to its environment. Several probiotics have been characterized and applied in fish and a number of them are of host origin. Unlike some disease control alternatives being adapted and proposed in aquaculture where actions are unilateral, the immense potential of probiotics lies on their multiple mechanisms in conferring benefits to the host fish and the rearing environment. The staggering number of probiotics papers in aquaculture highlights the multitude of advantages from these microorganisms and conspicuously position them in the dynamic search for health-promoting alternatives for cultured fish. This paper provides an update on the use of probiotics in finfish aquaculture, particularly focusing on their modes of action. It explores the contemporary understanding of their spatial and nutritional competitiveness, inhibitory metabolites, environmental modification capability, immunomodulatory potential and stress-alleviating mechanism. This timely update affirms the importance of probiotics in fostering sustainable approaches in aquaculture and provides avenues in furthering its research and development.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Titan's greenhouse and antigreenhouse effects

    Science.gov (United States)

    Mckay, Christopher P.; Pollack, James B.; Courtin, Regis

    1992-01-01

    Thermal mechanisms active in Titan's atmosphere are discussed in a brief review of data obtained during the Voyager I flyby in 1980. Particular attention is given to the greenhouse effect (GHE) produced by atmospheric H2, N2, and CH4; this GHE is stronger than that on earth, with CH4 and H2 playing roles similar to those of H2O and CO2 on earth. Also active on Titan is an antigreenhouse effect, in which dark-brown and orange organic aerosols block incoming solar light while allowing IR radiation from the Titan surface to escape. The combination of GHE and anti-GHE leads to a surface temperature about 12 C higher than it would be if Titan had no atmosphere.

  17. Strategic planning and greenhouse effect

    International Nuclear Information System (INIS)

    Corderoy, B.C.

    1990-01-01

    During former years of high load growth in New South Wales and elsewhere, the challenge for generation planners was to develop power station sites and associated transmission infrasture at a rage rapid enough to meet escalating community requirements for electricity. This challenge was met. The planners of today face a situation of far less certainty - load growth is fragile and at a lower level while the community expects that measures adopted will maintain accepted standards of reliability, be at a minimum level of financial risk and increasingly be environmentally benign. One particular environmental challenge is that posed by the greenhouse effect for which there is a further need to develop a much wider range of strategies. This involves better performance for existing plant, looking at different types of generating systems but also looking to the other side of the energy equation, demand site energy efficiency programs. These issues are briefly discussed

  18. Synthetic greenhouse gases under control

    International Nuclear Information System (INIS)

    Horisberger, B.; Karlaganis, G.

    2003-01-01

    This article discusses new Swiss regulations on the use of synthetic materials that posses a considerable greenhouse-warming potential. Synthetic materials such as hydro-chlorofluorocarbons HCFCs, perfluoride-hydrocarbons and sulphur hexafluoride have, in recent years, replaced chlorofluorocarbons CFCs, which were banned on account of their ozone depletion characteristics. The use of these persistent substances is now being limited to applications where more environment-friendly alternatives are not available. The measures decreed in the legislation, which include a general ban on HCFCs as of 2004 and a ban on the export of installations and equipment that use ozone-depleting refrigerants are described. Details on the legislation's effects on the Swiss refrigeration industry are listed and discussed

  19. Energy efficiency and greenhouse gases

    International Nuclear Information System (INIS)

    Hamburg, A.; Martins, A.; Pesur, A.; Roos, I.

    1996-01-01

    Estonia's energy balance for 1990 - 1994 is characterized by the dramatic changes in the economy after regaining independence in 1991. In 1990 - 1993, primary energy supply decreased about 1.9 times. The reasons were a sharp decrease in exports of electric energy and industrial products, a steep increase in fuel prices and the transition from the planned to a market-oriented economy. Over the same period, the total amount of emitted greenhouse gases decreased about 45%. In 1993, the decrease in energy production and consumption stopped, and in 1994, a moderate increase occurred (about 6%), which is a proof stabilizing economy. Oil shale power engineering will remain the prevailing energy resource for the next 20 - 25 years. After stabilization, the use of oil shale will rise in Estonia's economy. Oil shale combustion in power plants will be the greatest source of greenhouse gases emissions in near future. The main problem is to decrease the share of CO 2 emissions from the decomposition of carbonate part of oil shale. This can be done by separating limestone particles from oil shale before its burning by use of circulating fluidized bed combustion technology. Higher efficiency of oil shale power plants facilitates the reduction of CO 2 emissions per generated MWh electricity considerably. The prognoses for the future development of power engineering depend essentially on the environmental requirements. Under the highly restricted development scenario, which includes strict limitations to emissions (CO 2 , SO 2 , thermal waste) and a severe penalty system, the competitiveness of nuclear power will increase. The conceptual steps taken by the Estonian energy management should be in compliance with those of neighboring countries, including the development programs of the other Baltic states

  20. Analysis of politics about greenhouse effect

    International Nuclear Information System (INIS)

    Chetouani, L.; Tournier, M.

    1992-01-01

    This report deals with the greenhouse effect which brings about increasing temperatures. It is based upon documents such as interviews, conferences, political speeches, newspaper articles and so on. After the problem of the greenhouse effect has been exposed, a lexicometric study is carried out. The analysis of all the texts that have been studied finally leads to semiologic interpretations. (TEC). 2 tabs

  1. A Hiatus of the Greenhouse Effect

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  2. Optimal control of a solar greenhouse

    NARCIS (Netherlands)

    Ooteghem, van R.J.C.; Stigter, J.D.; Willigenburg, van L.G.; Straten, van G.

    2003-01-01

    A solar greenhouse has been designed that maximizes solar energy use and minimizes fossil energy consumption. It is based on a conventional greenhouse extended with a heat pump, a heat exchanger, an aquifer and ventilation with heat recovery. The aim is to minimize fossil energy consumption, while

  3. Greenhouse engineering: New technologies and approaches

    NARCIS (Netherlands)

    Montero, J.I.; Henten, van E.J.; Son, J.E.; Castilla, N.

    2011-01-01

    Firstly, this article discusses the greenhouse engineering situation in three geographic areas which are relevant in the field of protected cultivation: Northern Asia, The Netherlands and the Mediterranean. For each area, the prevailing greenhouse type and equipment is briefly described. Secondly,

  4. Greenhouse Gases Concentrations in the Atmosphere Along ...

    African Journals Online (AJOL)

    This study investigated effect of vehicular emission on greenhouse gases concentrations along selected roads of different traffic densities in Abeokuta, Ogun State, Nigeria. Nine roads comprised highway, commercial and residential were selected. Greenhouse Gases (GHGs) were determined from both sides of the roads by ...

  5. Seasonal variation of heat consumption in greenhouses

    DEFF Research Database (Denmark)

    Nielsen, O.F.; Amsen, M.G.; Strøm, J.S.

    The concept of dynamic variation is introduced as a method to visualize the dynamic fluctuations of heat consumption and thermal climate in greenhouses. The feasibility of the concept is illustrated by describing effects of different greenhouse designs. Engineering data on design heat consumption...

  6. A Hiatus of the Greenhouse Effect.

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-09-12

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth's surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown.

  7. A Hiatus of the Greenhouse Effect

    Science.gov (United States)

    Song, Jinjie; Wang, Yuan; Tang, Jianping

    2016-01-01

    The rate at which the global average surface temperature is increasing has slowed down since the end of the last century. This study investigates whether this warming hiatus results from a change in the well-known greenhouse effect. Using long-term, reliable, and consistent observational data from the Earth’s surface and the top of the atmosphere (TOA), two monthly gridded atmospheric and surface greenhouse effect parameters (Ga and Gs) are estimated to represent the radiative warming effects of the atmosphere and the surface in the infrared range from 1979 to 2014. The atmospheric and surface greenhouse effect over the tropical monsoon-prone regions is found to contribute substantially to the global total. Furthermore, the downward tendency of cloud activity leads to a greenhouse effect hiatus after the early 1990 s, prior to the warming pause. Additionally, this pause in the greenhouse effect is mostly caused by the high number of La Niña events between 1991 and 2014. A strong La Niña indicates suppressed convection in the tropical central Pacific that reduces atmospheric water vapor content and cloud volume. This significantly weakened regional greenhouse effect offsets the enhanced warming influence in other places and decelerates the rising global greenhouse effect. This work suggests that the greenhouse effect hiatus can be served as an additional factor to cause the recent global warming slowdown. PMID:27616203

  8. Greenhouse effect economic simulation and public decision

    International Nuclear Information System (INIS)

    Giraud, P.N.

    2002-03-01

    As the other countries, engaged in the greenhouse effect fight, the France has to evaluate the greenhouse gases emissions and the corrective actions. Meanwhile the today models are not enough impressive. The economic tools authorize today a better evaluation. The technical working Group, presided by Pierre-Noel Giraud, proposes to use them largely and provides four main recommendations. (A.L.B.)

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

    Directory of Open Access Journals (Sweden)

    Manuel Sardinha

    2014-06-01

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

  10. Modeling of greenhouse with PCM energy storage

    International Nuclear Information System (INIS)

    Najjar, Atyah; Hasan, Afif

    2008-01-01

    Greenhouses provide a controlled environment that is suitable for plants growth and cultivation. In this paper the maximum temperature change inside the greenhouse is to be reduced by the use of energy storage in a phase change material PCM. A mathematical model is developed for the storage material and for the greenhouse. The coupled models are solved using numerical methods and Java code program. The effect of different parameters on the inside greenhouse temperature is investigated. The temperature swing between maximum and minimum values during 24 h can be reduced by 3-5 deg. C using the PCM storage. This can be improved further by enhancing the heat transfer between the PCM storage and the air inside the greenhouse

  11. Modeling of greenhouse with PCM energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, Atyah [Computation Science, Birzeit University, Birzeit (PS); Hasan, Afif [Mechanical Engineering Department, Birzeit University, Birzeit (PS)

    2008-11-15

    Greenhouses provide a controlled environment that is suitable for plants growth and cultivation. In this paper the maximum temperature change inside the greenhouse is to be reduced by the use of energy storage in a phase change material PCM. A mathematical model is developed for the storage material and for the greenhouse. The coupled models are solved using numerical methods and Java code program. The effect of different parameters on the inside greenhouse temperature is investigated. The temperature swing between maximum and minimum values during 24 h can be reduced by 3-5 C using the PCM storage. This can be improved further by enhancing the heat transfer between the PCM storage and the air inside the greenhouse. (author)

  12. Nuclear energy and the greenhouse effect

    International Nuclear Information System (INIS)

    Weinberg, A.M.

    1990-01-01

    The extent and nature of the greenhouse effect are examined and placed in an environmental and historical context. The effect of energy policies on the greenhouse effect are discussed and the offending countries are identified. What energy policies would mitigate the greenhouse effect, and yet make good sense whether or not the effect proves to be real? Conservation is a desirable though not completely understood strategy. Conservation may not be a better bet in every instance than is increase in supply. If the greenhouse effect turns out to be real, nuclear energy can be one of the supply options that we turn to. If the greenhouse effect turns out to be false, and acceptable, economic nuclear option is surely better than one that does nothing but create strife and dissension. Let us remember that nuclear energy is the only large-scale non-fossil source other than hydropower that has been demonstrated to be practical. (author)

  13. Scientific perspectives on greenhouse problem. Part 2

    International Nuclear Information System (INIS)

    Jastrow, R.; Nierenberg, W.; Seitz, F.

    1992-01-01

    The spectre of major climate change caused by the greenhouse effect has generated intensive research, heated scientific debate and a concerted international effort to draft agreements for the reduction of greenhouse gas emissions. This report of Scientific Perspectives on the greenhouse problem explains the technical issues in the debate in language readily understandable to the non-specialist. The inherent complexities of attempts to simulate the earth's climate are explained, particularly with regard to the effects of clouds and the circulation of the oceans, which together represent the largest factors of uncertainty in current global warming forecasts. Results of the search for the 'greenhouse signal' in existing climate records aredescribed in chapter 3 (part two). Chapter 5 (part two) develops a projection of 21st-century warming based on relatively firm evidence of the earth's actual response to known increases in greenhouse gas emissions during the last 100 years

  14. GREENHOUSE GASES AND MEANS OF PREVENTION

    Directory of Open Access Journals (Sweden)

    Dušica Stojanović

    2013-09-01

    Full Text Available The greenhouse effect can be defined as the consequence of increased heating of the Earth's surface, as well as the lower atmosphere by carbon dioxide, water vapor, and other trace amounts gases. It is well-known that human industrial activities have released large amounts of greenhouse gases in the atmosphere, about 900 billion tons of carbon dioxide, and it is estimated that up to 450 billion are still in the atmosphere. In comparison to greenhouse gases water vapor is one of the greatest contributors to the greenhouse effect on Earth. Many projects, as does the PURGE project, have tendences to build on the already conducted research and to quantify the positive and negative impacts on health and wellbeing of the population with greenhouse gas reduction strategies that are curently being implemented and should be increasingly applied in various sectors and urban areas, having offices in Europe, China and India.

  15. Dispersal and assimilation of an aquaculture waste subsidy in a low productivity coastal environment.

    Science.gov (United States)

    White, C A; Nichols, P D; Ross, D J; Dempster, T

    2017-07-15

    To understand dispersal and assimilation of aquaculture waste subsidies in a naturally low-productivity environment, we applied a novel, rapid transmethylation technique to analyse sediment and biota fatty acid composition. This technique was initially validated at Atlantic salmon farms in Macquarie Harbour, Australia, where sediments were collected at farm and control locations. Subsequently, sediment, benthic polychaete and zooplankton were sampled at sites 0, 50, 250, 500 and 1000m distant from multiple cages. Results demonstrated an acute deposition zone up to 50m from cages and a diffuse zone extending 500m from cages. Changes in sediment concentration of linoleic acid, oleic acid and total fatty acids were effective tracers of farm deposition. Bacterial biomarkers indicated that aquaculture waste stimulates bacterial productivity in sediments, with elevated biomarker concentrations also detected in benthic polychaetes. Overall, fatty acid analysis was a sensitive technique to characterize the benthic footprint of aquaculture influence. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. 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...

  17. 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...

  18. 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...

  19. 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.

  20. 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...