WorldWideScience

Sample records for aquaculture system biofilters

  1. Degradation and effect of hydrogen peroxide in small-scale recirculation aquaculture system biofilters

    DEFF Research Database (Denmark)

    Møller, Martin Sune; Arvin, Erik; Pedersen, Lars-Flemming

    2010-01-01

    From an environmental point of view, hydrogen peroxide (HP) has beneficial attributes compared with other disinfectants in terms of its ready degradation and neutral by-products. The rapid degradation of HP can, however, cause difficulties with regard to safe and efficient water treatment when...... applied in different systems. In this study, we investigated the degradation kinetics of HP in biofilters from water recirculating aquaculture systems (RAS). The potential effect of HP on the nitrification process in the biofilters was also examined. Biofilter elements from two different pilot-scale RAS......−1 maintained over 3 h had a moderate inhibitory effect on the biofilter elements from one of the RAS with relatively high organic loading, while the nitrification was severely inhibited in the pilot-scale biofilters from the other RAS with a relatively low organic loading. A pilot-scale RAS...

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

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    of these agents on biofilter nitrification performance. All experiments were conducted through addition of chemical additives to closed pilot scale recirculating aquaculture systems (RAS) with fixed media submerged biofilters under controlled operating conditions with rainbow trout (Oncorhynchus mykiss...... to positively correlate to temperature, available biofilter surface-area, and the frequency of FA-exposure. Prolonged biofilter exposure to FA did not negatively affect nitrification, and could therefore be a method to optimize FA treatment in RAS and reduce FA discharge. HP degradation was rapid and could...... prolonged multiple HP dosages at 10 mg/L were found to inhibit nitrite oxidation in systems with low organic loading. PAA decay was found to be concentration-dependent. It had a considerable negative effect on nitrite oxidation over a prolonged period of time when applied at a dosage ≥2 mg/L. PAA and HP...

  3. 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....

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

    DEFF Research Database (Denmark)

    Prehn, Jonas; Waul, Christopher Kevin; Pedersen, Lars-Flemming

    2012-01-01

    Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS’s. The aim of this study was to det...... biofilters. The results may thus have practical implications in relation to the design, operational strategy of RAS biofilters and how to optimize TAN removal in fixed film biofilter systems......Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS’s. The aim of this study...

  5. 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

  6. Influence of fixed and moving bed biofilters on micro particle dynamics in a recirculating aquaculture system

    DEFF Research Database (Denmark)

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

    2017-01-01

    (Oncorhynchus mykiss), and operatedunder constant feed loading conditions (1 kg feed/m3of make-up water) for more than three months.Production or removal of micro particles according to biofilter mode of operation (FBB vs. MBB) wasassessed by operating all biofilters simultaneously as well as separately...... due to disintegration of particles inMBB. In the RAS, ammonia and nitrite were observed at concentrations below 0.20 mg N/L throughoutthe majority of the experiment. However, during the phase where only MBB were in operation, TAN(Total Ammonia Nitrogen) and nitrite levels increased significantly...

  7. Influence of fixed and moving bed biofilters on micro particle dynamics in a recirculating aquaculture system

    DEFF Research Database (Denmark)

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

    2017-01-01

    (Oncorhynchus mykiss), and operatedunder constant feed loading conditions (1 kg feed/m3of make-up water) for more than three months.Production or removal of micro particles according to biofilter mode of operation (FBB vs. MBB) wasassessed by operating all biofilters simultaneously as well as separately...... particle concentration also represented a 10% reduction in total particle surface area and particlevolume. In MBB, a 10% increase in particle concentration also represented a 10% increase in total particlesurface area, but had no effect on total particle volume. A volumetric reduction of particles >100 m...... due to disintegration of particles inMBB. In the RAS, ammonia and nitrite were observed at concentrations below 0.20 mg N/L throughoutthe majority of the experiment. However, during the phase where only MBB were in operation, TAN(Total Ammonia Nitrogen) and nitrite levels increased significantly...

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

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    be described as a concentration-dependent exponential decay. HP was found to be enzymatically eliminated by microorganisms, with degradation rates correlated to organic matter content and microbial abundance. Nitrification performance was not affected by HP when applied in dosages less than 30 mg/L, whereas...... prolonged multiple HP dosages at 10 mg/L were found to inhibit nitrite oxidation in systems with low organic loading. PAA decay was found to be concentration-dependent. It had a considerable negative effect on nitrite oxidation over a prolonged period of time when applied at a dosage ≥2 mg/L. PAA and HP...... decay patterns were significantly affected by water quality parameters, i.e. at low organic matter content HP degradation was impeded due to microbial inhibition. FISH analysis on biofilm samples from two different types of RAS showed that Nitrosomonas oligotropha was the dominant ammonia oxidizing...

  9. 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

  10. Development and performance of an alternative biofilter system.

    Science.gov (United States)

    Lee, D H; Lau, A K; Pinder, K L

    2001-01-01

    Step tracer tests were carried out on lab-scale biofilters to determine the residence time distributions (RTDs) of gases passing through two types of biofilters: a standard biofilter with vertical gas flow and a modified biofilter with horizontal gas flow. Results were used to define the flow patterns in the reactors. "Non-ideal flow" indicates that the flow reactors did not behave like either type of ideal reactor: the perfectly stirred reactor [often called a "continuously stirred tank reactor" (CSTR)] or the plug-flow reactor. The horizontal biofilter with back-mixing was able to accommodate a shorter residence time without the usual requirement of greater biofilter surface area for increased biofiltration efficiency. Experimental results indicated that the first bed of the modified biofilter behaved like two CSTRs in series, while the second bed may be represented by two or three CSTRs in series. Because of the flow baffles used in the horizontal biofilter system, its performance was more similar to completely mixed systems, and hence, it could not be modeled as a plug-flow reactor. For the standard biofilter, the number of CSTRs was found to be between 2 and 9 depending on the airflow rate. In terms of NH3 removal efficiency and elimination capacity, the standard biofilter was not as good as the modified system; moreover, the second bed of the modified biofilter exhibited greater removal efficiency than the first bed. The elimination rate increased as biofilter load increased. An opposite trend was exhibited with respect to removal efficiency.

  11. Phaeobacter grown in biofilters: a new strategy for the control of Vibrionaceae in aquaculture

    DEFF Research Database (Denmark)

    Prol García, María Jesús; Gomez, Marina; Sanchez, Lorenzo

    2014-01-01

    materials, but a multilayer biofilm was only observed in the ceramic biofilters. In sterile seawater, plastic and ceramic biofilters reduced Vibrio anguillarum and V. splendidus concentration in one-two Log after 24-48h, showing 10(2)-10(3)CFUmL(-1). Sintered glass biofilters only inactivated V. anguillarum...... showed the lowest detachment and, after 11days, Phaeobacter (10(6) bacteria center dot cm(-3)) covered more than 80% of biofilters total culturable bacteria. DGGE profiles showed that Phaeobacter biofilters stabilizes the green seawater bacterial microbiota....

  12. Evaluation of a cost effective technique for treating aquaculture water discharge using Lolium perenne Lam as a biofilter.

    Science.gov (United States)

    Nduwimana, André; Yang, Xiang-Long; Wang, Li-Ren

    2007-01-01

    Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN (total ammonia nitrogen), 90% for NO2(-)-N, 64.8% for NO3(-)-N while for floating plant bed system 82.7% for TAN, 82% for NO2(-)-N and 60.5% for NO3(-)-N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN (total nitrogen) and TP (total phosphorus) load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.

  13. Geminicoccus roseus gen. nov., sp. nov., an aerobic phototrophic Alphaproteobacterium isolated from a marine aquaculture biofilter

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Gößner, Anita S.; Drake, Harold L.

    2007-01-01

    A Gram-negative, strictly aerobic, diplococcoid bacterium (strain D2-3T) was isolated from the biofilter of a recirculating marine aquaculture system. Phylogenetic analysis of the 16S rRNA gene sequence of D2-3T indicated that the new organism occupied a novel lineage within the α-1 subclass...... of the DNA was 60.3±0.1 mol%. Phylogenetic, morphological, physiological, and biochemical analyses demonstrated that D2-3T represented a new aerobic phototrophic genus, for which the name Geminicoccus roseus gen. nov., sp. nov. is proposed for the type species (D2-3T=DSM 18922T=ATCC BAA-1445T)....

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    The particle size distribution (PSD) in a recirculating aquaculture system (RAS) was investigated duringa 24-h cycle. PSD was analyzed in water sampled at several locations in a recirculation loop containing a60-m drum filter, a submerged fixed-bed biofilter and a trickling filter.In relation...

  15. 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...

  16. Do benthic biofilters contribute to sustainability and restoration of the benthic environment impacted by offshore cage finfish aquaculture?

    International Nuclear Information System (INIS)

    Aguado-Gimenez, F.; Piedecausa, M.A.; Carrasco, C.; Gutierrez, J.M.; Aliaga, V.; Garcia-Garcia, B.

    2011-01-01

    Highlights: → Benthic biofilters were deployed under an offshore fish farm and in control locations. → We checked the farm influence on fouling, wild fish and sediment near the biofilters. → Fouling under the cages used fish farm-derived wastes, but at low efficiency. → Wild fish were more abundant in the biofilters located below the cages. → Despite these clear benefits, sediment quality around the biofilters did not improve. - Abstract: Benthic biofilters were deployed under a cage fish farm and in two reference locations to assess the influence of the farm on the biofilters and the surroundings, as well as to verify the usefulness of this technology as a mitigation tool. The biofilters underneath the farm recruited a fouling community practically identical to that of the control biofilters, which included a variety of trophic strategies. The former showed a higher 15 N enrichment, indicating that fouling beneath the farm was benefiting from the farm waste. The waste retention efficiency was low (0.02 g N m -2 month -1 ) beneath the farm. Benthic biofilters aggregated demersal wild fish around and within them. Pelagic wild fish also frequently used the biofilters beneath the farm, forming compact shoals around them. The increased complexity of the habitat below the fish farm enhanced biodiversity, but this improvement did not lead to the recovery of the sediments around the biofilters.

  17. Defluviimonas denitrificans gen. nov., sp. nov., and Pararhodobacter aggregans gen. nov., sp. nov., non-phototrophic Rhodobacteraceae from the biofilter of a marine aquaculture

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Drake, Harold L.; Schramm, Andreas

    2011-01-01

    Three Gram-negative bacterial strains were isolated from the biofilter of a recirculating marine aquaculture. They were non-pigmented rods, mesophiles, moderately halophilic, and showed chemoorganoheterotrophic growth on various sugars, fatty acids, and amino acids, with oxygen as electron acceptor......, but clearly separate from, the genera Rhodobacter, Rhodovulum, and Rhodobaca. Based on morphological, physiological, and 16S rRNA-based phylogenetic characteristics, the isolated strains are proposed as new species of two novel genera, Defluviimonas denitrificans gen. nov., sp. nov. (type strain D9-3T = DSM...

  18. 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…

  19. Nitrosomonas Nm143-like ammonia oxidizers and Nitrospira marina -like nitrite oxidizers dominate the nitrifier community in a marine aquaculture biofilm

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Gieseke, Armin; Schwermer, Carsten

    2008-01-01

    Zero-discharge marine aquaculture systems are an environmentally friendly alternative to conventional aquaculture. In these systems, water is purified and recycled via microbial biofilters. Here, quantitative data on nitrifier community structure of a trickling filter biofilm associated with a re......Zero-discharge marine aquaculture systems are an environmentally friendly alternative to conventional aquaculture. In these systems, water is purified and recycled via microbial biofilters. Here, quantitative data on nitrifier community structure of a trickling filter biofilm associated...

  20. Synergistic Effects of Micro-electrolysis-Photocatalysis on Water Treatment and Fish Performance in Saline Recirculating Aquaculture System

    OpenAIRE

    Ye, Zhangying; Wang, Shuo; Gao, Weishan; Li, Haijun; Pei, Luowei; Shen, Mingwei; Zhu, Songming

    2017-01-01

    A new physico-chemical process for TAN (total ammonia nitrogen) removal and disinfection is introduced in saline recirculating aquaculture system (RAS), in which the biofilter is replaced with an integrated electrolysis cell and an activated carbon filter. The electrolysis cell which is based on micro current electrolysis combined with UV-light was self-designed. After the fundamental research, a small pilot scale RAS was operated for 30 days to verify the technical feasibility. The system wa...

  1. 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...

  2. 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.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    This study investigated the effects of applying four fixed feed loadings to three replicated recirculating aquaculture systems (RAS) on water quality changes, nitrogenous balances and growth performance of rainbow trout (Oncorhynchus mykiss).Feed loadings ranged from 1.6 to 6.3kgfeed/m3 make-up...... water, with a constant make-up water renewal of 4.7% of total water volume per day in all twelve RAS. Fish densities ranged from 14 to 92kg/m3 during the prolonged trial of 10weeks. Selected water quality parameters were measured during two intensive sampling campaigns, evaluating biofilter...

  4. 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 ...

  5. 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 ...

  6. 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.

  7. Air purification from TCE and PCE contamination in a hybrid bioreactors and biofilter integrated system.

    Science.gov (United States)

    Tabernacka, Agnieszka; Zborowska, Ewa; Lebkowska, Maria; Borawski, Maciej

    2014-01-15

    A two-stage waste air treatment system, consisting of hybrid bioreactors (modified bioscrubbers) and a biofilter, was used to treat waste air containing chlorinated ethenes - trichloroethylene (TCE) and tetrachloroethylene (PCE). The bioreactor was operated with loadings in the range 0.46-5.50gm(-3)h(-1) for TCE and 2.16-9.02gm(-3)h(-1) for PCE. The biofilter loadings were in the range 0.1-0.97gm(-3)h(-1) for TCE and 0.2-2.12gm(-3)h(-1) for PCE. Under low pollutant loadings, the efficiency of TCE elimination was 23-25% in the bioreactor and 54-70% in the biofilter. The efficiency of PCE elimination was 44-60% in the bioreactor and 50-75% in the biofilter. The best results for the bioreactor were observed one week after the pollutant loading was increased. However, the process did not stabilize. In the next seven days contaminant removal efficiency, enzymatic activity and biomass content were all diminished. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    biofilter nitrite oxidation in low-intensity RAS but not in high-intensity RAS. The impact of HP exposure time on biofilter nitrification capacity was then assessed in biofilter bench-scale experiments with nitrite spiking. Exposure time was found to significantly affect nitrite oxidation. Compared...... with unexposed biofilter elements, nitrite oxidation was reduced more than 90% following 3 h of exposure to 15 mg HP/L, whereas 30 min of exposure had only minor negative effects on nitrite oxidation. The findings of this study demonstrate the potential for developing HP water treatment practices for RAS...... and contradict prevailing notions that HP cannot be used safely in RAS that employ biofiltration. The development of effective new HP treatment protocols for recirculating aquaculture could reduce the current dependence on formalin to improve water quality and control parasitic loads...

  9. Temporal and Spatial Stability of Ammonia-Oxidizing Archaea and Bacteria in Aquarium Biofilters

    KAUST Repository

    Bagchi, Samik

    2014-12-05

    Nitrifying biofilters are used in aquaria and aquaculture systems to prevent accumulation of ammonia by promoting rapid conversion to nitrate via nitrite. Ammonia-oxidizing archaea (AOA), as opposed to ammonia-oxidizing bacteria (AOB), were recently identified as the dominant ammonia oxidizers in most freshwater aquaria. This study investigated biofilms from fixed-bed aquarium biofilters to assess the temporal and spatial dynamics of AOA and AOB abundance and diversity. Over a period of four months, ammonia-oxidizing microorganisms from six freshwater and one marine aquarium were investigated at 4–5 time points. Nitrogen balances for three freshwater aquaria showed that active nitrification by aquarium biofilters accounted for ≥81–86% of total nitrogen conversion in the aquaria. Quantitative PCR (qPCR) for bacterial and thaumarchaeal ammonia monooxygenase (amoA) genes demonstrated that AOA were numerically dominant over AOB in all six freshwater aquaria tested, and contributed all detectable amoA genes in three aquarium biofilters. In the marine aquarium, however, AOB outnumbered AOA by three to five orders of magnitude based on amoA gene abundances. A comparison of AOA abundance in three carrier materials (fine sponge, rough sponge and sintered glass or ceramic rings) of two three-media freshwater biofilters revealed preferential growth of AOA on fine sponge. Denaturing gel gradient electrophoresis (DGGE) of thaumarchaeal 16S rRNA genes indicated that community composition within a given biofilter was stable across media types. In addition, DGGE of all aquarium biofilters revealed low AOA diversity, with few bands, which were stable over time. Nonmetric multidimensional scaling (NMDS) based on denaturing gradient gel electrophoresis (DGGE) fingerprints of thaumarchaeal 16S rRNA genes placed freshwater and marine aquaria communities in separate clusters. These results indicate that AOA are the dominant ammonia-oxidizing microorganisms in freshwater aquarium

  10. Temporal and Spatial Stability of Ammonia-Oxidizing Archaea and Bacteria in Aquarium Biofilters

    KAUST Repository

    Bagchi, Samik; Vlaeminck, Siegfried E.; Sauder, Laura A.; Mosquera, Mariela; Neufeld, Josh D.; Boon, Nico; Poulain, Alexandre

    2014-01-01

    Nitrifying biofilters are used in aquaria and aquaculture systems to prevent accumulation of ammonia by promoting rapid conversion to nitrate via nitrite. Ammonia-oxidizing archaea (AOA), as opposed to ammonia-oxidizing bacteria (AOB), were recently identified as the dominant ammonia oxidizers in most freshwater aquaria. This study investigated biofilms from fixed-bed aquarium biofilters to assess the temporal and spatial dynamics of AOA and AOB abundance and diversity. Over a period of four months, ammonia-oxidizing microorganisms from six freshwater and one marine aquarium were investigated at 4–5 time points. Nitrogen balances for three freshwater aquaria showed that active nitrification by aquarium biofilters accounted for ≥81–86% of total nitrogen conversion in the aquaria. Quantitative PCR (qPCR) for bacterial and thaumarchaeal ammonia monooxygenase (amoA) genes demonstrated that AOA were numerically dominant over AOB in all six freshwater aquaria tested, and contributed all detectable amoA genes in three aquarium biofilters. In the marine aquarium, however, AOB outnumbered AOA by three to five orders of magnitude based on amoA gene abundances. A comparison of AOA abundance in three carrier materials (fine sponge, rough sponge and sintered glass or ceramic rings) of two three-media freshwater biofilters revealed preferential growth of AOA on fine sponge. Denaturing gel gradient electrophoresis (DGGE) of thaumarchaeal 16S rRNA genes indicated that community composition within a given biofilter was stable across media types. In addition, DGGE of all aquarium biofilters revealed low AOA diversity, with few bands, which were stable over time. Nonmetric multidimensional scaling (NMDS) based on denaturing gradient gel electrophoresis (DGGE) fingerprints of thaumarchaeal 16S rRNA genes placed freshwater and marine aquaria communities in separate clusters. These results indicate that AOA are the dominant ammonia-oxidizing microorganisms in freshwater aquarium

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

    Science.gov (United States)

    Schmidt, Victor; Amaral-Zettler, Linda; Davidson, John; Summerfelt, Steven; Good, Christopher

    2016-08-01

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

  12. Commercial production of tiger puffer ( Takifugu rubripes) in winter using a recirculating aquaculture system

    Science.gov (United States)

    Lin, Zhongling; Wang, Hua; Yu, Chunyan; Lv, Fenghe; Liu, Hengming; Zhang, Tao

    2017-02-01

    Tiger puffer ( Takifugu rubripes) is a promising species for aquaculture production because of its high value and limited supply. However, in the north of China, using sea cages to culture this species in winter is hampered by the fact that the seawater temperature is extremely low. Here, a large scale commercial production of tiger puffer has been successfully realized using a recirculating aquaculture system (RAS) from 3 October 2012 to 31 May 2013. The RAS was comprised of nine culture tanks (total water volume 200 m3) and stocked with approximately a total of 14400 fish (initial mean weight 160 g). The tiger puffer was hand-fed at a rate of 0.7% of total body weight per day, and the feed conversion rate was (1.21 ± 0.3) kg kg-1. The recycle water in RAS was treated by a sieve bend screen, a foam fractionator, a submerged biofilter, an UV sterilizer and a submersible aerator. During the whole culture period, an excellent water quality control was achieved in RAS. At the end of this experiment, the survival rate of tiger puffer was more than 98%. The final tank densities averaged 31.2 kg m-3, and the final individual mean weight was 440 g.

  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, 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.

  14. Application of two-stage biofilter system for the removal of odorous compounds.

    Science.gov (United States)

    Jeong, Gwi-Taek; Park, Don-Hee; Lee, Gwang-Yeon; Cha, Jin-Myeong

    2006-01-01

    Biofiltration is a biological process which is considered to be one of the more successful examples of biotechnological applications to environmental engineering, and is most commonly used in the removal of odoriferous compounds. In this study, we have attempted to assess the efficiency with which both single and complex odoriferous compounds could be removed, using one- or two-stage biofiltration systems. The tested single odor gases, limonene, alpha-pinene, and iso-butyl alcohol, were separately evaluated in the biofilters. Both limonene and alpha-pinene were removed by 90% or more EC (elimination capacity), 364 g/m3/h and 321 g/m3/h, respectively, at an input concentration of 50 ppm and a retention time of 30 s. The iso-butyl alcohol was maintained with an effective removal yield of more than 90% (EC 375 g/m3/h) at an input concentration of 100 ppm. The complex gas removal scheme was applied with a 200 ppm inlet concentration of ethanol, 70 ppm of acetaldehyde, and 70 ppm of toluene with residence time of 45 s in a one- or two-stage biofiltration system. The removal yield of toluene was determined to be lower than that of the other gases in the one-stage biofilter. Otherwise, the complex gases were sufficiently eliminated by the two-stage biofiltration system.

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

    Directory of Open Access Journals (Sweden)

    Luana Granada

    2014-05-01

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

  16. 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...

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

    Science.gov (United States)

    Troell, Max; Naylor, Rosamond L.; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H.; Folke, Carl; Arrow, Kenneth J.; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R.; Gren, 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

  18. 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...

  19. The abundance and diversity of heterotrophic bacteria as a function of harvesting frequency of duckweed (Lemna minor L.) in recirculating aquaculture systems.

    Science.gov (United States)

    Ardiansyah, A; Fotedar, R

    2016-07-01

    Duckweed (Lemna minor L.) is a potential biofilter for nutrient removal and acts as a substrate for heterotrophic bacteria in recirculating aquaculture systems (RAS). Here, we determined the effects of harvesting frequency of duckweed on heterotrophic bacteria in RAS. Twelve independent RAS consisting of fish-rearing tank, biofilter tank and waste-collection tank were used to study the interactions between duckweed harvest frequencies up to 6 days and the composition, abundance and diversity of heterotrophic bacteria. After 36 days, heterotrophic bacteria in the biofilter tank were primarily Gram-negative cocci or ovoid, coccobacilli, Gram-negative bacilli and Gram-positive bacilli. Most bacterial genera were Bacillus and Pseudomonas while the least common was Acinetobacter. Duckweed harvested after every 2 days produced the highest specific growth rates (SGR) and total harvested biomass of duckweed, but harboured less abundant bacteria, whereas 6-day harvests had a higher growth index (GI) of duckweed than 2-day harvests, but caused a poor relationship between SGR and biomass harvest with the abundance and diversity of heterotrophic bacteria. Stronger correlations (R(2)  > 0·65) between duckweed SGR and biomass harvest with the heterotrophic bacteria diversity were observed at 4-day harvest frequency and the control. This study provides significant information on the interaction between the harvest frequency of duckweed and the composition, abundance and diversity of heterotrophic bacteria in recirculating aquaculture systems (RAS). Different harvest frequencies significantly influence the abundance and diversity of heterotrophic bacteria, which in turn may influence the nitrogen uptake efficiency of the system. The research is useful in improving the efficiency of removing nitrogenous metabolites in RAS directly by the duckweed and associated heterotrophic bacteria. © 2016 The Society for Applied Microbiology.

  20. 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...

  1. Intestinal microbiota of healthy and unhealthy Atlantic salmon Salmo salar L. in a recirculating aquaculture system

    Science.gov (United States)

    Wang, Chun; Sun, Guoxiang; Li, Shuangshuang; Li, Xian; Liu, Ying

    2018-03-01

    The present study sampled the intestinal content of healthy and unhealthy Atlantic salmon ( Salmo salar L.), the ambient water of unhealthy fish, and the biofilter material in the recirculating aquaculture system (RAS) to understand differences in the intestinal microbiota. The V4-V5 regions of the prokaryotic 16S rRNA genes in the samples were analyzed by MiSeq high-throughput sequencing. The fish were adults with no differences in body length or weight. Representative members of the intestinal microbiota were identified. The intestinal microbiota of the healthy fish included Proteobacteria (44.33%), Actinobacteria (17.89%), Bacteroidetes (15.25%), and Firmicutes (9.11%), among which the families Micrococcaceae and Oxalobacteraceae and genera Sphingomonas, Streptomyces, Pedobacter, Janthinobacterium, Burkholderia, and Balneimonas were most abundant. Proteobacteria (70.46%), Bacteroidetes (7.59%), and Firmicutes (7.55%) dominated the microbiota of unhealthy fish, and Chloroflexi (2.71%), and Aliivibrio and Vibrio as well as genera in the family Aeromonadaceae were most strongly represented. Overall, the intestinal hindgut microbiota differed between healthy and unhealthy fish. This study offers a useful tool for monitoring the health status of fish and for screening the utility of probiotics by studying the intestinal microbiota.

  2. 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

  3. 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...

  4. 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.

  5. 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 ...

  6. 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

  7. Nitrogen removal capacity and bacterial community dynamics of a Canon biofilter system at different organic matter concentrations.

    Science.gov (United States)

    García-Ruiz, María J; Maza-Márquez, Paula; González-López, Jesús; Osorio, Francisco

    2018-02-01

    Three Canon bench-scale bioreactors with a volume of 2 L operating in parallel were configured as submerged biofilters. In the present study we investigated the effects of a high ammonium concentration (320 mgNH 4 + · L -1 ) and different concentrations of organic matter (0, 100 and 400 mgCOD·L -1 ) on the nitrogen removal capacity and the bacterial community structure. After 60 days, the Canon biofilters operated properly under concentrations of 0 and 100 mgCOD·L -1 of organic matter, with nitrogen removal efficiencies up to 85%. However, a higher concentration of organic matter (400 mgCOD·L -1 ) produced a partial inhibition of nitrogen removal (68.1% efficiency). The addition of higher concentrations of organic matter a modified the bacterial community structure in the Canon biofilter, increasing the proliferation of heterotrophic bacteria related to the genera of Thauera, Longilinea, Ornatilinea, Thermomarinilinea, unclassified Chlorobiales and Denitratisoma. However, heterotrophic bacteria co-exist with Nitrosomonas and Candidatus Scalindua. Thus, our study confirms the co-existence of different microbial activities (AOB, Anammox and denitrification) and the adaptation of a fixed-biofilm system to different concentrations of organic matter. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. INDUSTRIAL GAS PURIFICATION USE OF BIOFILTERS

    Directory of Open Access Journals (Sweden)

    Irina Ramona PECINGINĂ

    2012-05-01

    Full Text Available Biological filtration systems is one of the current alternatives to remove residual volatile components of the air through biological means, without affecting the natural environment. Biofilters have a technology that uses microorganisms (bacteria to treat emissions, in a secure economic and environmental quality. Biofilters consist of porous filters, which is distributed flue gas stream

  9. 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

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

    Science.gov (United States)

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

    2015-01-01

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

  11. New approaches to improve the removal of dissolved organic matter and nitrogen in aquaculture

    DEFF Research Database (Denmark)

    von Ahnen, Mathis

    further due to the lack of cost-effective and easy applicable treatment methods for removing dissolved N and OM. The purpose of this PhD thesis was to assess the problem of removing dissolved N and OM in the context of the large differences in system intensity between farms, and to devise new, simple...... at increasing long-term waste loadings. The second part examined the potential of using anoxic denitrifying woodchip bioreactors for removal of nitrate from aquaculture effluent (Paper III-V). Investigations within the first part showed that the effectiveness of biofilters, as determined by their areal removal......-term biofilter loading up to a certain threshold. The latter indicated that the removal capacity of biofilters operated at lower loadings is easily exceeded, and that they may not respond very well to sudden increases in total ammonia nitrogen (TAN) concentrations. In the second part of the thesis, a field study...

  12. 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...

  13. 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

  14. Synergistic Effects of Micro-electrolysis-Photocatalysis on Water Treatment and Fish Performance in Saline Recirculating Aquaculture System

    Science.gov (United States)

    Ye, Zhangying; Wang, Shuo; Gao, Weishan; Li, Haijun; Pei, Luowei; Shen, Mingwei; Zhu, Songming

    2017-03-01

    A new physico-chemical process for TAN (total ammonia nitrogen) removal and disinfection is introduced in saline recirculating aquaculture system (RAS), in which the biofilter is replaced with an integrated electrolysis cell and an activated carbon filter. The electrolysis cell which is based on micro current electrolysis combined with UV-light was self-designed. After the fundamental research, a small pilot scale RAS was operated for 30 days to verify the technical feasibility. The system was stocked by 42 GIFT tilapia (Oreochromis niloticus) fish with the rearing density of 13 kg/m3. During the experiments, the TAN concentration remained below 1.0 mg/L. The nitrite concentration was lower than 0.2 mg/L and the nitrate concentration had increased continuously to 12.79 mg/L at the end. Furthermore, the concentration of residual chlorine in culture ponds remained below 0.3 mg/L, ORP maintained slight fluctuations in the range of 190~240 mV, and pH of the water showed the downtrend. Tilapia weight increased constantly to 339.3 ± 10 g. For disinfection, the active chlorine generated by electrochemical treatment caused Escherichia coli inactivation. Enzyme activity assay indicated that the activity of glutamate dehydrogenase, carbonic anhydrase and glutamic pyruvic transaminase increased within the normal range. The preliminary feasibility was verified by using this physico-chemical technology in the RAS.

  15. Synergistic Effects of Micro-electrolysis-Photocatalysis on Water Treatment and Fish Performance in Saline Recirculating Aquaculture System.

    Science.gov (United States)

    Ye, Zhangying; Wang, Shuo; Gao, Weishan; Li, Haijun; Pei, Luowei; Shen, Mingwei; Zhu, Songming

    2017-03-27

    A new physico-chemical process for TAN (total ammonia nitrogen) removal and disinfection is introduced in saline recirculating aquaculture system (RAS), in which the biofilter is replaced with an integrated electrolysis cell and an activated carbon filter. The electrolysis cell which is based on micro current electrolysis combined with UV-light was self-designed. After the fundamental research, a small pilot scale RAS was operated for 30 days to verify the technical feasibility. The system was stocked by 42 GIFT tilapia (Oreochromis niloticus) fish with the rearing density of 13 kg/m 3 . During the experiments, the TAN concentration remained below 1.0 mg/L. The nitrite concentration was lower than 0.2 mg/L and the nitrate concentration had increased continuously to 12.79 mg/L at the end. Furthermore, the concentration of residual chlorine in culture ponds remained below 0.3 mg/L, ORP maintained slight fluctuations in the range of 190~240 mV, and pH of the water showed the downtrend. Tilapia weight increased constantly to 339.3 ± 10 g. For disinfection, the active chlorine generated by electrochemical treatment caused Escherichia coli inactivation. Enzyme activity assay indicated that the activity of glutamate dehydrogenase, carbonic anhydrase and glutamic pyruvic transaminase increased within the normal range. The preliminary feasibility was verified by using this physico-chemical technology in the RAS.

  16. 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.

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

    Science.gov (United States)

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

    2011-12-15

    Geosmin and 2-methylisoborneol (MIB) have been associated with off-flavour problems in fish and seafood products, generating a strong negative impact for aquaculture industries. Although most of the producers of geosmin and MIB have been identified as Streptomyces species or cyanobacteria, Streptomyces spp. are thought to be responsible for the synthesis of these compounds in indoor recirculating aquaculture systems (RAS). The detection of genes involved in the synthesis of geosmin and MIB can be a relevant indicator of the beginning of off-flavour events in RAS. Here, we report a real-time polymerase chain reaction (qPCR) protocol targeting geoA sequences that encode a germacradienol synthase involved in geosmin synthesis. New geoA-related sequences were retrieved from eleven geosmin-producing Actinomycete strains, among them two Streptomyces strains isolated from two RAS. Combined with geoA-related sequences available in gene databases, we designed primers and standards suitable for qPCR assays targeting mainly Streptomyces geoA. Using our qPCR protocol, we succeeded in measuring the level of geoA copies in sand filter and biofilters in two RAS. This study is the first to apply qPCR assays to detect and quantify the geosmin synthesis gene (geoA) in RAS. Quantification of geoA in RAS could permit the monitoring of the level of geosmin producers prior to the occurrence of geosmin production. This information will be most valuable for fish producers to manage further development of off-flavour events. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Modeling of TAN in recirculating aquaculture systems by AQUASIM

    DEFF Research Database (Denmark)

    Arvin, Erik; Pedersen, Lars-Flemming

    2011-01-01

    in Hirtshals, Denmark (Pedersen et al., 2009). Water from the fish rearing tank is treated in a sedimentation tank and subsequently by biological treatment in a submerged biofilter and in a trickling filter. Generally, the performance of the biological treatment was very well and average TAN concentrations...

  19. 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

  20. 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

  1. 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...

  2. 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

  3. 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

  4. Development of an integrated multi-trophic aquaculture (IMTA system for tropical marine species in southern cebu, Central Philippines

    Directory of Open Access Journals (Sweden)

    Danilo B. Largo

    2016-05-01

    Full Text Available This study presents the establishment of an integrated multi-trophic aquaculture (IMTA system in the tropical open waters of southern Cebu, Philippines using a combination of locally available species, namely donkey’s ear abalone (Haliotis asinina as fed species and seaweeds (Gracilaria heteroclada and Eucheuma denticulatum as inorganic extractive species. The culture of Caulerpa lentillifera as a biofilter did not work in the open sea cultivation system using baskets. Monthly measurements of shell length, width and body weight of the cultured abalones, together with in situ measurements of physicochemical parameters to assess any changes in water quality, mainly nitrate, nitrite, ammonia and phosphate, were conducted over a year period from February 2013 to January 2014 in three designated stations (Abalone, Seaweed and Control Stations at three different depths (surface, middle and bottom.Cage culture of abalone side by side with seaweeds in the open sea did not result in any significant water quality disturbance in the area—at least not in the current volume of caged abalones being used. Of the four inorganic compounds monitored in the field, nitrate and ammonia in the Seaweed Station were shown to have relatively lower year-round average values when compared with the Abalone Station, although in the case of nitrate, it was higher in the Control Station compared with the abalone and Seaweed Stations. Although this difference was not significant, it shows the red seaweeds, G. heteroclada and E. denticulatum, to be functioning as a natural filter for these two nutrients. In contrast, nitrite, and phosphate concentrations were not reduced indicating that the seaweeds were not effective biofilter for these two nutrients.The two-month old hatchery-bred donkey’s ear abalones can grow to a size of 53.8 × 28.2 mm (L × W and body weight of 37.8 g after a period of 12 months. Any expansion of the farm into a much larger commercial

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

    Directory of Open Access Journals (Sweden)

    M Gullian-Klanian

    2013-03-01

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

  6. Relevance and diversity of Nitrospira populations in biofilters of brackish RAS.

    Directory of Open Access Journals (Sweden)

    Myriam Kruse

    Full Text Available Lithoautotrophic nitrite-oxidizing bacterial populations from moving-bed biofilters of brackish recirculation aquaculture systems (RAS; shrimp and barramundi were tested for their metabolic activity and phylogenetic diversity. Samples from the biofilters were labeled with (13C-bicarbonate and supplemented with nitrite at concentrations of 0.3, 3 and 10 mM, and incubated at 17 and 28°C, respectively. The biofilm material was analyzed by fatty acid methyl ester - stable isotope probing (FAME-SIP. High portions of up to 45% of Nitrospira-related labeled lipid markers were found confirming that Nitrospira is the major autotrophic nitrite oxidizer in these brackish systems with high nitrogen loads. Other nitrite-oxidizing bacteria such as Nitrobacter or Nitrotoga were functionally not relevant in the investigated biofilters. Nitrospira-related 16S rRNA gene sequences were obtained from the samples with 10 mM nitrite and analyzed by a cloning approach. Sequence studies revealed four different phylogenetic clusters within the marine sublineage IV of Nitrospira, though most sequences clustered with the type strain of Nitrospira marina and with a strain isolated from a marine RAS. Three lipids dominated the whole fatty acid profiles of nitrite-oxidizing marine and brackish enrichments of Nitrospira sublineage IV organisms. The membranes included two marker lipids (16∶1 cis7 and 16∶1 cis11 combined with the non-specific acid 16∶0 as major compounds and confirmed these marker lipids as characteristic for sublineage IV species. The predominant labeling of these characteristic fatty acids and the phylogenetic sequence analyses of the marine Nitrospira sublineage IV identified organisms of this sublineage as main autotrophic nitrite-oxidizers in the investigated brackish biofilter systems.

  7. 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).

  8. 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...

  9. 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.

  10. Selection of commercial biofilters for rearing aquatic animals in closed system

    Directory of Open Access Journals (Sweden)

    Chuayrodmod, J.

    2007-07-01

    Full Text Available A comparative study was made to select the most suitable biofilter from 7 types of commercial water filters by rearing hybrid catfish (Clarias macrocephalus x C. gariepinus in aquaria for 64 days. It was found that diminishing concentrations of ammonia and nitrite were attributed mainly to nitrifying bacteria that convert ammonia into nitrite and nitrate which required a minimum period of 16-28 days for the process to function. Low absorption of ammonia was achieved through using activated carbon, coconut shell charcoal, zeolite and ceramic. Durability and filtering efficiency of the filters depended upon porosity and amount of biofilm on the filter surface. The filter using one coarse meshed plastic sheet and 37 bioballs was the most suitable, though it caused a problem with low total alkalinity resulting in mortality of the biofilm which peeled off, thus increasing the concentrations of ammonia, nitrite and suspended solids toward the end of the experimental period. The catfish growth rate, survival and FCR in all treatments were in the ranges of 7.39-8.91 g/d, 84.44-95.56% and 0.21-0.25, respectively.

  11. 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).

  12. 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.

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

    Science.gov (United States)

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

    2014-02-01

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

  14. 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.

  15. 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.

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

    Science.gov (United States)

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

    2013-01-01

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

  17. 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.

  18. 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...

  19. 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.

  20. Efficiency of Different Integrated Agriculture Aquaculture Systems in the Red River Delta of Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen Van Huong

    2018-02-01

    Full Text Available Integrated Agriculture Aquaculture (IAA is characteristic with diversity of small-scale production systems in the Red River Delta, Vietnam where most integrated aquaculture systems are closely associated to the VAC model, an ecosystem production that three components: garden (V, pond (A and livestock pen (C are integrated. These VAC systems effectively use all the available land, air, water and solar energy resources, and also effectively recycle by-products and waste for providing diversified agricultural products to meet the complex nutritional demands of rural communities. The IAA systems are dynamic, diverse and subject to economic and environmental changes. By investigating 167 aquaculture households, the traditional VAC, New VAC, Animal Fish (AF and Commercial Fish (FS systems are identified as four existing IAA systems. This paper presents the main characteristics and economic efficiency of these IAA systems. The study’s results indicate clear evidence that the traditional VAC system and New VAC system are the most efficient and effective models. The findings of this study have shed light on the important role of integrated aquaculture systems to food security and economic development of households and local communities. The VAC systems are likely to propose for improving household food security and developing the local economy.

  1. Design and Development of Smart Aquaculture System Based on IFTTT Model and Cloud Integration

    Directory of Open Access Journals (Sweden)

    Dzulqornain Muhammad Iskandar

    2018-01-01

    Full Text Available The internet of things technology (IoT is growing very rapidly. IoT implementation has been conducted in several sectors. One of them is for aquaculture. For the traditional farmers, they face problems for monitoring water quality and the way to increase the quality of the water quickly and efficiently. This paper presents a real-time monitoring and controlling system for aquaculture based on If This Then That (IFTTT model and cloud integration. This system was composed of smart sensor module which supports modularity, smart aeration system for controlling system, local network system, cloud computing system and client visualization data. In order to monitor the water condition, we collect the data from smart sensor module. Smart sensor module consists of sensor dissolved oxygen, potential of hydrogen, water temperature and water level. The components of smart aeration system are microcontroller NodeMCU v3, relay, power supply, and propeller that can produce oxygen. The system could set the IFTTT rules for the ideal water condition for the pond in any kinds of aquaculture based on its needs through the web and android application. The experimental result shows that use IFTTT model makes the aquaculture monitoring system more customizable, expandable and dynamic.

  2. 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.

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  4. Earthy and musty off-flavor episodes in catfish split-pond aquaculture systems

    Science.gov (United States)

    The interest and use of variations of partitioned aquaculture systems (PAS) by the southeastern U.S. catfish farming industry continues to grow. Split-pond systems, one type of PAS, are designed to improve management of dissolved oxygen levels and fish waste products (e.g., ammonia) compared to conv...

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

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

    Science.gov (United States)

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

  7. Integrated agriculture-aquaculture systems in the Mekong Delta, Vietnam: an analysis of recent trends

    NARCIS (Netherlands)

    Thanh Phong, Le; Udo, H.M.J.; Mensvoort, van M.E.F.; Bosma, R.H.; Quang Tri, Le; Nhan, D.K.; Zijpp, van der A.J.

    2008-01-01

    In order to explain the trends in the development and farm attributes of Integrated Agriculture-Aquaculture (IAA) systems in the Mekong Delta of Vietnam, a participatory community appraisal and two surveys are carried out in three districts with contrasting fish culture input systems. The first

  8. A Monitoring and Control System for Aquaculture via Wireless Network and Android Platform

    Directory of Open Access Journals (Sweden)

    Juan Huan

    2014-04-01

    Full Text Available Web applications, databases and advanced mobile platform can facilitate real-time data acquisition for effective monitoring on intelligent agriculture. To improve facilities for aquaculture production automation and efficient, this paper presents an application for wireless network and Android platform that interacts with an advanced control system based on Apache, SQL Server, Java, to collect and monitor variables applied in aquaculture. The test and application shows that is stable, high price-performance ratio, good mobility and easy to operate, It has a strong practicality and application prospects.

  9. Bacterial activity dynamics in the water phase during start-up of recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Rojas-Tirado, Paula Andrea; Pedersen, Per Bovbjerg; Pedersen, Lars-Flemming

    2017-01-01

    tMicrobial water quality in recirculating aquaculture systems (RAS) is important for successful RAS opera-tion but difficult to assess and control. There is a need to identify factors affecting changes in the bacterialdynamics – in terms of abundance and activity – to get the information needed...

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

    Science.gov (United States)

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

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

    Science.gov (United States)

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

  12. Biodiesel Production by the Green Microalga Scenedesmus obliquus in a Recirculatory Aquaculture System

    Science.gov (United States)

    Mandal, Shovon

    2012-01-01

    Biodiesel production was examined with Scenedesmus obliquus in a recirculatory aquaculture system with fish pond discharge and poultry litter to couple with waste treatment. Lipid productivity of 14,400 liter ha−1 year−1 was projected with 11 cultivation cycles per year. The fuel properties of the biodiesel produced adhered to Indian and international standards. PMID:22660702

  13. Adoption of Recirculating Aquaculture Systems in Pangasius Farms: A Choice Experiment

    NARCIS (Netherlands)

    Pham, T.A.N.; Gielen-Meuwissen, M.P.M.; Le, T.T.; Bosma, R.H.; Oude Lansink, A.G.J.M.

    2015-01-01

    A growing number of European customers’ demands certified pangasius such as ASC in order to ensure sustainable production. Implementing Recirculating Aquaculture Systems (RAS) contributes to an improved water quality, a key issue in achieving ASC certification. This study uses a choice experiment to

  14. Adoption of Recirculating Aquaculture Systems in Large Pangasius Farms: A Choice Experiment

    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

    A growing number of European customers’ demands certified pangasius such as ASC in order to ensure sustainable production. Implementing Recirculating Aquaculture Systems (RAS) contributes to an improved water quality, a key issue in achieving ASC certification. This study uses a choice experiment to

  15. Evaluation of commercial marine fish feeds for production of juvenile cobia in recirculating aquaculture systems

    Science.gov (United States)

    The effect of feeding three commercially available diets manufactured by three U.S. feed companies on production characteristics and body composition of juvenile cobia Rachycentron canadum reared in recirculating aquaculture systems (RAS) was evaluated in a 57 d growth trial. Juvenile cobia (26.7 +...

  16. Water cortisol and testosterone in Nile tilapia (Oreochromis niloticus) recirculating aquaculture systems

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    The accumulation of steroids released by fish in recirculating aquaculture systems (RAS) may potentially influence their physiology and behavior. The present study examined the release rate of cortisol and testosterone by Nile tilapia, Oreochromis niloticus, and their accumulation in six identical

  17. 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.

  18. FluoRAS Sensor - Online organic matter for optimising recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Hambly, Adam; Stedmon, Colin

    2018-01-01

    FluorRAS will develop a sensor that can save recycled fish farms 30% per year in water and energy consumption for water treatment, as well as optimize nitrogen removal. The sensor will be developed in a partnership between engineers (Krüger A / S) and researchers (DTU), and the product will be made...... both the maintenance of necessary water quality and water treatment costs. Loss of production due to poor water quality is expensive and can be avoided with correct sensor systems. Accumulation of dissolved organic matter and nutrients in the water reduce the effectiveness of UV treatment, is a source...... of nutrition for opportunistic pathogens, and reduces the effectiveness of the biofilter's removing ammonia. Modern recycling systems are therefore dependent on a network of online sensors that monitor and respond to changes in water quality, but currently there is a need for a sensor to monitor...

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

    Science.gov (United States)

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

    2017-06-01

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

  20. TREATMENT OF VOLATILE ORGANIC COMPOUNDS IN WASTE GASES USING A TRICKLING BIOFILTER SYSTEM: A MODELING APPROACH

    Science.gov (United States)

    Biofiltration represents a novel strategy for controlling VOC emissions from a variety of industrial processes. As commercial applications of these systems increase, sophisticated theoretical models will be useful in establishing design criteria for providing insights into impor...

  1. Integrated nitrogen removal biofilter system with ceramic membrane for advanced post-treatment of municipal wastewater.

    Science.gov (United States)

    Son, Dong-Jin; Yun, Chan-Young; Kim, Woo-Yeol; Zhang, Xing-Ya; Kim, Dae-Gun; Chang, Duk; Sunwoo, Young; Hong, Ki-Ho

    2016-12-01

    The pre-denitrification biofilm process for nitrogen removal was combined with ceramic membrane with pore sizes of 0.05-0.1 µm as a system for advanced post-treatment of municipal wastewater. The system was operated under an empty bed hydraulic retention time of 7.8 h, recirculation ratio of 3, and transmembrane pressure of 0.47 bar. The system showed average removals of organics, total nitrogen, and solids as high as 93%, 80%, and 100%, respectively. Rapid nitrification could be achieved and denitrification was performed in the anoxic filter without external carbon supplements. The residual particulate organics and nitrogen in effluent from biofilm process could be also removed successfully through membrane filtration and the removal of total coliform was noticeably improved after membrane filtration. Thus, a system composed of the pre-denitrification biofilm process with ceramic membrane would be a compact and flexible option for advanced post-treatment of municipal wastewater.

  2. Treatment of turtle aquaculture effluent by an improved multi-soil-layer system.

    Science.gov (United States)

    Song, Ying; Huang, Yu-ting; Ji, Hong-fang; Nie, Xin-jun; Zhang, Zhi-yuan; Ge, Chuan; Luo, An-cheng; Chen, Xin

    2015-02-01

    Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer (MSL) systems treating turtle aquaculture effluent with adding different amounts of sludge. Four MSL systems were constructed with dry weight ratios of sludge with 0%, 5%, 10%, and 20% (MSL 1, MSL 2, MSL 3, and MSL 4, respectively). The turtle aquaculture effluent had an average chemical oxygen demand (COD), ammonia nitrogen (NH4(+)-N) and total nitrogen (TN) concentration of 288.4, 213.4, and 252.0 mg/L, respectively. The COD/TN (C/N) ratio was 1.2. The results showed that the four MSL systems could effectively treat the COD, NH4(+)-N, and TN, and MSL 4 showed significantly improved NH4(+)-N removal efficiency, suggesting the potential of sludge addition to improve the turtle aquaculture effluent treatment. The average COD, TN, and NH4(+)-N removal efficiencies of MSL 4 were 70.3%, 66.5%, and 72.7%, respectively. To further interpret the contribution of microorganisms to the removal, the microbial community compositions and diversities of the four MSL systems were measured. Comparisons of the denaturing gradient gel electrophoresis (DGGE) profiles revealed that the amount of nitrifying bacteria and diversity in MSL 4 were higher than those in the other three systems. We concluded that adding 20% of sludge improved the NH4(+)-N removal and stability of the system for nitrification, due to the enrichment of the nitrifying bacteria in MSL 4.

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

    DEFF Research Database (Denmark)

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

    2018-01-01

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

  4. Systemic granuloma observed in Atlantic salmon Salmo salar raised to market size in a freshwater recirculation aquaculture system

    Science.gov (United States)

    Systemic granuloma was observed in sampled adult Atlantic salmon Salmo salar raised to harvest size in a freshwater recirculation aquaculture system. The prevalence of this condition was estimated at 10-20% of the population, with affected individuals grossly demonstrating pathology in varying degre...

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

    Science.gov (United States)

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

    2012-01-01

    The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified and antimicrobial and toxic metal susceptibility patterns were determined. Overall, 407 representative strains were recovered. In general, bacteria isolated from fish ponds showed higher multiple antibiotic resistance indices when compared to those isolated from a water-fed canal. Resistance to penicillin and azithromycin was observed more frequently in the GPC group, whereas resistance to ampicillin and ampicillin/sulbactam or gentamicin was observed more frequently in the ENT and NFR groups, respectively. All the isolated bacteria were tolerant to nickel, zinc, chromium and copper at high levels (≥1,024 μg mL−1), whereas tolerance to cadmium and mercury varied among the isolated bacteria (2–1,024 μg mL−1). Multidrug-resistant bacteria were more frequent and diverse in fish ponds than in the water-fed canal. A positive correlation was observed between antimicrobial resistance and metal tolerance. The data point out the need for water treatment associated with the aquaculture system. PMID:22972388

  6. Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor(R)-medicated feed therapy (20 mg/kg BW/d for 10 days)

    Science.gov (United States)

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

    2013-01-01

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

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    on a daily basis as compared to untreated systems. In systems intermittently treated with formalin, increased variation and minor reductions of ammonium and nitrite oxidation rates were observed. Nitrifying bacteria were screened by specific gene probes using fluorescence in situ hybridization and quantified...... Nitrobacter sp. was not detected. The relative abundances of AOB and NOB in the untreated system were generally higher compared to the system exposed to formalin. Low dose formalin in recirculated aquaculture systems proved to be a possible treatment strategy, as the effect on nitrification was minimal. Since...

  8. Biofilter odour reduction level, measurements; Luktreduceringsgrad hos biofilter, faeltmaetningar

    Energy Technology Data Exchange (ETDEWEB)

    Arrhenius, Karine; Rosell, Lars; Tsetsilas, Sakis (SP, Boraas (Sweden)); Loevenklev, Maria; Blomqvist, Marie; Hall, Gunnar; Sverken, Anna; Widen, Helene (SIK, Goeteborg (Sweden)); Holmgren, Magnus Andreas (Vattenfall Power Consultants (Sweden))

    2010-07-01

    Biofilter is today the most common odour reduction method for biological treatment. A biofilter consists of a bed of organic material often made of compost together with another material which increases the porosity of the bed. Microorganisms in the compost use odorous compounds as nutrient by decomposing them. Resulting products are mainly carbon dioxide and water, mineral salts, other organic compounds and more microorganisms. In this project, seven biofilters implemented in Sweden have been tested in order to describe their status and function. A number of physical, chemical, microbiological and odour related parameters have be measured in the pipe which leads to the biofilter as well as on the surface of the biofilter in order to determine biofilters status and their effectiveness. Values from plants have been compared to published optimal values for each parameter. The goal of the project is to optimize biofilters function och prevent risks for performance disturbances. Results from the project can also be used as reference for plants which are planning process modifications as an increase of waste to be treated, substrate/material changes etc. Each plant has been visited during two days in August/September 2009. The following parameters have been measured: 1) physical parameters such as relative humidity, temperature, and pH, 2) chemical parameters such as incoming and out coming gas composition, gas composition variation with time, access to nutriments, 3) microbiological parameters such as the total number of microorganisms and the dominating microflora i respective biofilter and 4) odour related parameters through an evaluation of the contribution of individual compounds to the total out coming odour and in some cases, through a evaluation by olfactometry. All these parameters have been subsequently interpreted and treated in order to evaluate the status of the biofilter: description of the biofilter, its environment, the microbiological status, which flow

  9. Effects of temperature on nitrous oxide (N2O) emission from intensive aquaculture system.

    Science.gov (United States)

    Paudel, Shukra Raj; Choi, Ohkyung; Khanal, Samir Kumar; Chandran, Kartik; Kim, Sungpyo; Lee, Jae Woo

    2015-06-15

    This study examines the effects of temperature on nitrous oxide (N2O) emissions in a bench-scale intensive aquaculture system rearing Koi fish. The water temperature varied from 15 to 24 °C at interval of 3 °C. Both volumetric and specific rate for nitrification and denitrification declined as the temperature decreased. The concentrations of ammonia and nitrite, however, were lower than the inhibitory level for Koi fish regardless of temperature. The effects of temperature on N2O emissions were significant, with the emission rate and emission factor increasing from 1.11 to 1.82 mg N2O-N/d and 0.49 to 0.94 mg N2O-N/kg fish as the temperature decreased from 24 to 15 °C. A global map of N2O emission from aquaculture was established by using the N2O emission factor depending on temperature. This study demonstrates that N2O emission from aquaculture is strongly dependent on regional water temperatures as well as on fish production. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Sulfide oxidation in a biofilter

    DEFF Research Database (Denmark)

    Pedersen, Claus Lunde; Dezhao, Liu; Hansen, Michael Jørgen

    Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

  11. Sulfide oxidation in a biofilter

    DEFF Research Database (Denmark)

    Pedersen, Claus Lunde; Liu, Dezhao; Hansen, Michael Jørgen

    2012-01-01

    Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

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

    Science.gov (United States)

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

    2014-12-01

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

  13. Salmonella Weltevreden in integrated and non-integrated tilapia aquaculture systems in Guangdong, China

    DEFF Research Database (Denmark)

    Li, Kang; Petersen, Gitte; Barco, Lisa

    2017-01-01

    including transmission of faecal zoonotic pathogens and accumulation of antimicrobial and other chemical residues. This study aimed to determine differences in occurrence and characteristics of Salmonella spp. isolated from tilapia-pig and non-integrated aquaculture systems in Guangdong province, China...... method showed a clonal relationship of S. Weltevreden which was supported by similar antimicrobial resistance patterns (sulfamethoxazole and trimethoprim resistance) as well as most isolates harbouring a 147-kb sized plasmid. The common finding of S. Weltevreden in both tilapia production systems...

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

    Science.gov (United States)

    Trent, J. D.

    2013-12-01

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

  15. Salmonella Weltevreden in integrated and non-integrated tilapia aquaculture systems in Guangdong, China.

    Science.gov (United States)

    Li, Kang; Petersen, Gitte; Barco, Lisa; Hvidtfeldt, Kristian; Liu, Liping; Dalsgaard, Anders

    2017-08-01

    Integrated tilapia-pig farming, which uses manure from pigs as fertilizers in fish pond, is a traditional and common production system practised by small-scale farmers in South-east Asia. Although such systems may be environmentally sustainable, they also pose potential food safety hazards including transmission of faecal zoonotic pathogens and accumulation of antimicrobial and other chemical residues. This study aimed to determine differences in occurrence and characteristics of Salmonella spp. isolated from tilapia-pig and non-integrated aquaculture systems in Guangdong province, China. A total of 77 samples (9 pig feed, 19 fish feed, 9 pig faeces, 20 fish mucus and 20 fish intestine) from 10 tilapia-pig ponds and 10 non-integrated ponds were analysed. Salmonella spp. was found in fish mucus (20.0%), fish intestine (40.0%) and pig faeces (11.1%) from integrated ponds, and from fish mucus (40.0%) and fish intestine (40.0%) from non-integrated ponds. S. Weltevreden (76.5%) was by far the most common serovar showing limited antimicrobial resistance. One pig faeces sample contained S. Typhimurium whereas feed samples were found free of Salmonella spp.. DNA fingerprinting by the PFGE method showed a clonal relationship of S. Weltevreden which was supported by similar antimicrobial resistance patterns (sulfamethoxazole and trimethoprim resistance) as well as most isolates harbouring a 147-kb sized plasmid. The common finding of S. Weltevreden in both tilapia production systems indicates that this serovar may have a different ecology and increased survival in aquaculture environments in comparison with other Salmonella serovars. Further in vivo studies of the ecology of S. Weltevreden in aquaculture environments are needed. Copyright © 2017. Published by Elsevier Ltd.

  16. Nitrite oxidizing bacteria for water treatment in coastal aquaculture system

    Science.gov (United States)

    Noorak, S.; Rakkhiaw, S.; Limjirakhajornt, K.; Uppabullung, A.; Keawtawee, T.; Sangnoi, Y.

    2018-04-01

    This research aimed to isolate and characterize nitrite oxidizing bacteria and to study their capability for water quality improvement. Fourteen strains of bacteria with nitrite-oxidizing character were isolated after 21 days of enrichment in Pep-Beef-NOB medium contained NaNO2. Two strains, SF-1 and SF-5, showed highest nitrite removal rate for 42.42% and 37.2%, respectively. These strains were determined an efficiency of open-system wastewater treatment for 14 days. The results showed that control, SF-1 and SF-5 had remove ammonia from day 1 to day 6. At the end of the study, ammonia was removed by the control, SF-1 and SF-5 for 81.27%, 70.1% and 69.82%, respectively. Nitrite concentration was lowest at day 8 with removal rate of 98.73%, 98.3% and 97.24% from control, SF-1 and SF-5, respectively. However, nitrite concentration in control experiment was increased again at day 11 whereas in SF-1 and SF-5 were increased at day 13. Chemical Oxygen Demand (COD) was decreased by 77.78%, 73.50% and 78.63% in the control, SF-1 and SF-5, respectively. Biological Oxygen Demand (BOD) in the control, SF-1 and SF-5 were reduced by 85.92%, 79.53% and 82.09%, respectively. Based on 16S rRNA gene, SF-1 and SF-5 were identified as Bacillus vietnamensis and B. firmus, respectively.

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

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming

    2011-01-01

    of water sanitation with PAA application were used to analytically verify actual PAA concentration under real conditions at different kinds of aquaculture systems. A characteristic instant disinfection demand was found to be significantly positively related to water COD content, and PAA half-lives were...... found to be in the order of a few minutes. The study revealed that PAA degrades so rapidly that insufficient disinfection is a likely outcome. The observations have applications for optimizing water treatment strategies with PAA. The investigations also indicated that the rapid degradation and hence...

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    Allan T Souza

    2015-12-01

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

  20. Prediction of required ozone dosage for pilot recirculating aquaculture systems based on laboratory studies

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Rojas-Tirado, Paula Andrea; Kaarsholm, Kamilla Marie Speht

    2017-01-01

    In recirculating aquaculture systems (RAS), the water quality changes continuously. Organic and inorganic compounds accumulates creating toxic conditions for the farmed organisms. Ozone improves water quality diminishing significantly both bacteria load and dissolved organic matter. However......, in a non-meticulously designed system, residual ozone might reach the culture tanks causing significant harm to cultured species or excess costs. The aim of the study was to predict the suitable ozone dosage in pilot RAS, for water treatment purposes, based on laboratory studies. The ozone effect on water...... quality of freshwater RAS and system’s ozone demand was investigated. Bench-scale ozonation experiments revealed the ozone demand of the system to be 180 mg O3/h. Three different ozone dosages were applied to four replicated systems with fixed feed loading (1.56 kg feed/m3 make up water). Results...

  1. Oxygen Consumption of Tilapia and Preliminary Mass Flows through a Prototype Closed Aquaculture System

    Science.gov (United States)

    Muller, Matthew S.; Bauer, Clarence F.

    1994-01-01

    Performance of NASA's prototype CELSS Breadboard Project Closed Aquaculture System was evaluated by estimating gas exchange quantification and preliminary carbon and nitrogen balances. The total system oxygen consumption rate was 535 mg/hr kg/fish (cv = 30%) when stocked with Tilapia aurea populations (fresh weights of 97 +/- 19 to 147 +/- 36 g/fish for various trials). Oxygen consumption by T. aurea (260 mg/hr kg/fish) contributed to approximately one-half of total system demand. Continuous carbon dioxide quantification methods were analyzed using the,relation of carbon dioxide to oxygen consumption. Overall food conversion rates averaged 18.2 +/- 3.2%. Major pathways for nitrogen and carbon in the system were described with preliminary mass closure of 60-80% and 60% for nitrogen and carbon.

  2. 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].

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

    Science.gov (United States)

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

    2012-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Serbulov Alexey

    2012-03-01

    Full Text Available This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

  5. 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...

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

    Directory of Open Access Journals (Sweden)

    M. Angélica Garrido-Pereira

    2014-11-01

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

  7. 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.

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

    International Nuclear Information System (INIS)

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

    2003-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-05-01

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

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

    Science.gov (United States)

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

    2016-08-24

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

  11. 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...

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

    Science.gov (United States)

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

  13. The effects of ozonation on select waterborne steroid hormones in recirculation aquaculture systems containing sexually mature Atlantic salmon Salmo salar

    Science.gov (United States)

    A controlled 3-month study was conducted in 6 replicated water recirculation aquaculture systems (RAS) containing a mixture of sexually mature and immature Atlantic salmon Salmo salar to determine whether water ozonation is associated with a reduction in waterborne hormones. Post-smolt Atlantic salm...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    Single-sludge denitrification (DN) reactors in aquaculture utilize the solid fish waste produced in the system to reduce the nitrate load discharged. The solid waste is available for denitrifiers when present in soluble readily biodegradable form. A transformation accomplished by bacterial hydrol...

  16. Evaluation of a low-head recirculating aquaculture system used for rearing Florida pompano to market size

    Science.gov (United States)

    A low-head recirculating aquaculture system (RAS) was evaluated for the production Florida pompano Trachinotus carolinus from juvenile to market size. The RAS consisted of three dual-drain, 3-m diameter culture tanks of 7.8 m3 volume each, two 0.7-m3 moving bed bioreactors filled 67% with K1 kaldnes...

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

    NARCIS (Netherlands)

    Nhan, D.K.

    2007-01-01

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

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

    Science.gov (United States)

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

  19. The impact of water exchange rate on the health and performance of rainbow trout Oncorhynchus mykiss in recirculation aquaculture systems

    Science.gov (United States)

    Fish mortality in recirculating aquaculture systems (RAS) has been observed by the authors to increase when RAS are managed at low makeup water exchange rates with relatively high feed loading. The precise etiology of this elevated mortality was unknown, all typical water quality parameters were wit...

  20. Cortisol and testosterone accumulation in a low pH recirculating aquaculture system for rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    Steroids accumulate in recirculating aquaculture system (RAS), although explanatory factors for such accumulation are still poorly explored. This study investigated the effect of water exchange rate and pH in six replicated RAS on the concentration of the stress hormone cortisol in rainbow trout

  1. Peracetic acid degradation in freshwater aquaculture systems and possible practical implications

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Meinelt, Thomas; Straus, David L.

    2013-01-01

    , and it decays rapidly when applied to freshwater in aquaculture systems. The rapid decay is beneficial in an environmental context but a challenge to aquaculturists. To assess the impact of organic matter content and temperature on PAA decay, twenty-four batch experiments were set up using PAA doses ranging...... from 0 to 2.0 mg/l. The results revealed that increasing organic matter content significantly facilitated PAA decay, and positive temperature-decay correlations were found. Instantaneous PAA consumption above 0.2 mg/l was observed, and PAA half-lives were found to be in the order of a few minutes....... The relative PAA recovery, calculated as measured PAA concentration over time compared to the PAA concentration applied, decreased with declining dose. Measurements of PAA residuals during water treatment scenarios at three different freshwater fish farms revealed moderate to substantial PAA consumption...

  2. Hematologic and plasma chemistry RIs for cultured Striped catfish (Pangasius hypophthalmus) in recirculating aquaculture systems.

    Science.gov (United States)

    Galagarza, Oscar A; Kuhn, David D; Smith, Stephen A; Hrubec, Terry C

    2017-09-01

    Striped catfish (Pangasius hypophthalmus) is a valuable aquaculture fish species produced primarily in Southeast Asia. In the United States, it is bred as an ornamental species. Striped catfish has high productivity and great demand in numerous countries around the world, yet little is known about its normal physiology. The objective of this study was to establish hematologic and blood chemistry RIs for healthy juvenile Striped catfish. Blood samples were collected from 70 Striped catfish raised in recirculating aquaculture systems. Whole blood and plasma samples were analyzed for multiple hematologic and chemistry variables using standard techniques. The RIs for hematology were as follows: PCV 23.5-35.9%, MCV 106.3-156.6 fL, RBC count 1.79-2.75 × 10 6 cells/μL, thrombocytes 26,318-73,333 cells/μL, total WBC count 36,294-94,286 cells/μL, total lymphocytes 18,997-59,998 cells/μL, small lymphocytes 13,763-51,490 cells/μL, large lymphocytes 715-21,200 cells/μL, granulocytes 4504-18,291 cells/μL, and monocytes 0-7549 cells/μL. Plasma chemistry RIs were the following: ALP 32.7-74.6 U/L, AST 20.3-1235.8 U/L, sodium 135.2-147.7 mmol/L, potassium 3.3-5.0 mmol/L, chloride 120.1-133.6 mmol/L, calcium 2.7-3.6 mmol/L, magnesium 0.9-1.3 mmol/L, phosphorous 1.4-2.7 mmol/L, glucose 4.6-7.6 mmol/L, cholesterol 2.8-5.3 mmol/L, total protein 30-42 g/L, albumin 7-11 g/L, globulin 22-32 g/L, albumin:globulin ratio 0.27-0.37, creatinine 0-8 μmol/L, and osmolality 251.8-327.9 mOsm/kg. Reference intervals reported here can help veterinarians and fish health specialists monitor the health status of Striped catfish under recirculating aquaculture conditions for research, exhibition, and production purposes. © 2017 American Society for Veterinary Clinical Pathology.

  3. Dracaena marginata biofilter: design of growth substrate and treatment of stormwater runoff.

    Science.gov (United States)

    Vijayaraghavan, K; Praveen, R S

    2016-01-01

    The purpose of this research was to investigate the efficiency of Dracaena marginata planted biofilters to decontaminate urban runoff. A new biofilter growth substrate was prepared using low-cost and locally available materials such as red soil, fine sand, perlite, vermiculite, coco-peat and Sargassum biomass. The performance of biofilter substrate was compared with local garden soil based on physical and water quality parameters. Preliminary analyses indicated that biofilter substrate exhibited desirable characteristics such as low bulk density (1140 kg/m(3)), high water holding capacity (59.6%), air-filled porosity (7.82%) and hydraulic conductivity (965 mm/h). Four different biofilter assemblies, with vegetated and non-vegetated systems, were examined for several artificial rain events (un-spiked and metal-spiked). Results from un-spiked artificial rain events suggested that concentrations of most of the chemical components in effluent were highest at the beginning of rain events and thereafter subsided during the subsequent rain events. Biofilter growth substrate showed superior potential over garden soil to retain metal ions such as Al, Fe, Cu, Cr, Ni, Zn, Cd and Pb during metal-spiked rain events. Significant differences were also observed between non-vegetated and vegetated biofilter assemblies in runoff quality, with the latter producing better results.

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

    Science.gov (United States)

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

    2017-07-01

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

  5. An efficient water conditioning system for land-based abalone aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Davis, C.P. [University of Edinburgh (United Kingdom). School of GeoSciences; Carrington, C.G. [University of Otago, Dunedin (New Zealand). Dept. of Physics

    2005-07-01

    Data collected from a single grow-out tank in an abalone farm in southern New Zealand has highlighted hygiene maintenance problems in the use of semi-closed water conditioning systems for the aquaculture of New Zealand black foot abalone Haliotis iris. The data shows that semi-closed systems can have high concentrations of un-ionized ammonia, which is harmful to the animals. In this paper an alternative open flow-through system is suggested where energy demand is limited by heat recovery at the grow-out tank outlet. Using temperature data collected over 1 year, and a previously obtained expression for standing losses, a simple energy model is presented for an open system with heat recovery. To compliment the energy model, a function has been established for abalone production with respect to the concentration of un-ionized ammonia and water temperature. The energy model and production function are combined to determine the impact of plant design and tank conditions on the economics of the operation for the southern New Zealand climate. It is demonstrated that temperature control is financially preferable to an open system with no temperature control, and estimates of optimum operating conditions are given. (author)

  6. 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...

  7. Biomass production and nitrogen dynamics in an integrated aquaculture/agriculture system

    Science.gov (United States)

    Owens, L. P.; Hall, C. R.

    1990-01-01

    A combined aquaculture/agriculture system that brings together the three major components of a Controlled Ecological Life Support System (CELSS) - biomass production, biomass processing, and waste recycling - was developed to evaluate ecological processes and hardware requirements necessary to assess the feasibility of and define design criteria for integration into the Kennedy Space Center (KSC) Breadboard Project. The system consists of a 1 square meter plant growth area, a 500 liter fish culture tank, and computerized monitoring and control hardware. Nutrients in the hydrophonic solution were derived from fish metabolites and fish food leachate. In five months of continuous operation, 27.0 kg of lettuce tops, 39.9 kg of roots and biofilm, and 6.6 kg of fish (wet weights) were produced with 12.7 kg of fish food input. Based on dry weights, a biomass conversion index of 0.52 was achieved. A nitrogen budget was derived to determine partitioning of nitrogen within various compartments of the system. Accumulating nitrogen in the hypoponic solution indicated a need to enlarge the plant growth area, potentially increasing the biomass production and improving the biomass conversion index.

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

    OpenAIRE

    Nhan, D.K.

    2007-01-01

    In the Mekong delta, the Vietnamese government promoted integrated agriculture-aquaculture (IAA) farming systems as an example of sustainable agriculture. An important advantage of IAA-farming is the nutrient linkage between the pond and terrestrial components within a farm, which allows to improve resource use efficiency and income while reducing environmental impacts. This study monitored and analyzed water use in and nutrient flows through ponds that are part of an IAA-farming system. Th...

  9. Profiling bacterial communities associated with sediment-based aquaculture bioremediation systems under contrasting redox regimes

    Science.gov (United States)

    Robinson, Georgina; Caldwell, Gary S.; Wade, Matthew J.; Free, Andrew; Jones, Clifford L. W.; Stead, Selina M.

    2016-12-01

    Deposit-feeding invertebrates are proposed bioremediators in microbial-driven sediment-based aquaculture effluent treatment systems. We elucidate the role of the sediment reduction-oxidation (redox) regime in structuring benthic bacterial communities, having direct implications for bioremediation potential and deposit-feeder nutrition. The sea cucumber Holothuria scabra was cultured on sediments under contrasting redox regimes; fully oxygenated (oxic) and redox stratified (oxic-anoxic). Taxonomically, metabolically and functionally distinct bacterial communities developed between the redox treatments with the oxic treatment supporting the greater diversity; redox regime and dissolved oxygen levels were the main environmental drivers. Oxic sediments were colonised by nitrifying bacteria with the potential to remediate nitrogenous wastes. Percolation of oxygenated water prevented the proliferation of anaerobic sulphate-reducing bacteria, which were prevalent in the oxic-anoxic sediments. At the predictive functional level, bacteria within the oxic treatment were enriched with genes associated with xenobiotics metabolism. Oxic sediments showed the greater bioremediation potential; however, the oxic-anoxic sediments supported a greater sea cucumber biomass. Overall, the results indicate that bacterial communities present in fully oxic sediments may enhance the metabolic capacity and bioremediation potential of deposit-feeder microbial systems. This study highlights the benefits of incorporating deposit-feeding invertebrates into effluent treatment systems, particularly when the sediment is oxygenated.

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

    Directory of Open Access Journals (Sweden)

    Puchong Sri-uam

    2016-06-01

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

  11. Aquaculture Information Package

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, T.; Rafferty, K. [editors

    1998-01-01

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

  12. Report of the FAO Asian Region Workshop on Geographical Information Systems Applications in Aquaculture: Bangkok, Thailand, 5-23 December 1988

    National Research Council Canada - National Science Library

    1989-01-01

    The objective of the Workshop was to train aquaculturists in the use of geographical information systems as a means to provide comprehensive information for policy and planning for aquaculture development...

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

    Directory of Open Access Journals (Sweden)

    Saleem Mustafa

    2015-11-01

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

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

    Directory of Open Access Journals (Sweden)

    Lili Carrera

    2013-03-01

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

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Sudeep Puthravilakom Sadasivan Nair

    2010-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Dibo Liu

    2016-11-01

    Full Text Available Integrated multi-trophic aquaculture (IMTA is a promising direction for the sustainable development of aquaculture. Microalgae have good potential to be integrated with recirculating aquaculture systems because they can use the nitrogen excreted from fish and share the same optimal pH value as in aquaculture. As a byproduct, the microalgae biomass can be used for fish feed or biofuel. However, the recirculating fish-microalgae IMTA system is under constant threat from fish pathogens and phytoplankton-lytic bacteria. Therefore, it is necessary to apply proper disinfectants as prophylaxis or treatment which are effective against these threats, but safe to fish and microalgae. For this purpose, peracetic acid (PAA is a valid option because it is highly effective against fish pathogens and bacteria at low concentrations and degrades spontaneously to harmless residues. In the present study, we exposed the culture of a marine microalgae Tetraselmis chuii once per day for four days to four PAA products with differing hydrogen peroxide (H2O2/PAA proportions at two concentrations (1 and 2 mg L−1 PAA. The H2O2 solutions at equivalent total peroxide (H2O2 + PAA concentrations were tested in parallel. The results show that the growth and photosynthesis of T. chuii were not affected by three of the PAA products (Wofasteril® E400, Wofasteril® E250 and Applichem® 150 and equivalent H2O2 solutions at both concentrations. In contrast, Wofasteril® Lspez and an equivalent H2O2 solution at both concentrations caused irreversible culture collapse, photosynthesis dysfunction and irreversible cell damage. In conclusion, PAA products with low proportions of H2O2 are optimal disinfectants for fish-microalgae IMTA systems.

  18. Exploration of indigenous bacteria in an intensive aquaculture system of African catfish (Clarias sp.) in Banyuwangi, Indonesia

    Science.gov (United States)

    Prayogo; Rahardja, B. S.; Asshanti, A. N.; Dewi, N. N.; Santanumurti, M. B.

    2018-04-01

    Intensive African catfish culture in tarpaulin pond was popular in Banyuwangi, Indonesia since the government supported the fisheries sector. Unfortunately, the failure of African catfish culture still occurred since the waste from fish metabolite process and feed residue decreased the water quality. Bacteria in the water could be the solution to increase the success rate of aquaculture by improving the water quality. This study purpose was to obtained indigenous bacteria in intensive aquaculture system of African catfish to improve water quality. This study successfully isolated bacteria contained with amylase, protease and lipase characteristic. Isolated bacteria in this study were identified as Pseudomonas pseudomallei (97.81%), Bacillus subtilis (95.81%) and Pseudomonas stutzeri (61.21%).

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

    Science.gov (United States)

    Carbone, Donatella; Faggio, Caterina

    2016-07-01

    Infectious diseases in fish represent a major problem for the aquaculture field as they produce extensive damages and loss. Over the last few years, with increased development of the aquaculture industry, different methods have been used to contrast these pathologies. Common interest has led to the use of components (as additives in diets) that could contrast diseases without causing any negative impact on the environment. These components are represented by prebiotics, probiotics, and plant extracts. In this review, the effects of prebiotics are described. Prebiotics are indigestible fibres fermented by gut enzymes and commensal bacteria, whose beneficial effects are due to the by-products generated from fermentation. The influence of pre-biotics on the immune system of fish is called immunosaccharides. Mannanoligosaccharides (MOS), Fructooligosaccharides (FOS) and Inulin act at different levels in the innate immune response. For example, through phagocytosis, lysozyme activity, and the complement system activity, an increase in fish growth and an amelioration of their health status is brought about. In this review, the use of prebiotics in aquaculture, such as immunostimulants, has been highlighted: particularly in two teleost fish species, Sparus aurata and Dicentrarchus labrax. The results demonstrate that the road is still long and further studies are required, but the use of prebiotics, individually or coupled together, can open the doors to pioneering a new model of alternative components to antimicrobial agents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 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.

  1. 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.

  2. A High Performance Biofilter for VOC Emission Control.

    Science.gov (United States)

    Wu, G; Conti, B; Leroux, A; Brzezinski, R; Viel, G; Heitz, M

    1999-02-01

    Biofiltration is a cleaning technique for waste air contaminated with some organic compounds. The advantages of the conventional biofilter over other biological systems are a high-superficial area best suited for the treatment of some compounds with poor water solubility, ease of operation, and low operating costs. It has crucial disadvantages, however; for example, it is not suitable to treat waste gases with high VOC concentrations and it has poor control of reaction conditions. To improve on these problems and to build a high-performance biofilter, three structured peat media and two trickling systems have been introduced in this study. The influences of media size and composition have been investigated experimentally. Peat bead blended with 30% (w/w) certain mineral material with a good binding capacity has advantages over other packing materials, for example, suitable size to prevent blockage due to microbial growth, strong buffering capacity to neutralize acidic substances in the system, and a pH range of 7.0-7.2 suitable for the growth of bacteria. Dropwise trickling system offers an effective measure to easily control the moisture content of the bed and the reaction conditions (pH, nutrient) and to partially remove excess biomass produced during the metabolic processes of microorganisms. The influence of nutrient supplementation has also been investigated in this study, which has revealed that the biological system was in a condition of nutrient limitation instead of carbon limitation. The biofilters built in our laboratory were used to treat waste gas contaminated with toluene in a concentration range of 1 to 3.2 g/m 3 and at the specific gas flow rate of 24 to120 m 3 /m 2 .hr. Under the conditions employed, a high elimination capacity (135 g/m 3 .hr) was obtained in the biofilter packed with peat beads (blended with 30% of the mineral material), and no blockage problem was observed in an experimental period of 2-3 months.

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

    NARCIS (Netherlands)

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

    2015-01-01

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

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

    NARCIS (Netherlands)

    Verdegem, M.C.J.

    2013-01-01

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

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    ) was constructed as a part of the IMPAQ project “IMProvement of AQuaculture high quality fish fry production”. We present recent advance within RAS culture for copepods, and lesson learned from rearing the specie. Further we present physical and biological culture restrictions in terms of water quality (NH3...

  6. ECONOMIC ANALYSIS OF FRESHWATER AQUACULTURE PRODUCTION: A COMPARATIVE ANALYSIS OF DIFFERENT PRODUCTION SYSTEMS

    Directory of Open Access Journals (Sweden)

    H. Kumar

    2013-01-01

    Full Text Available India produced 8.29 million tonnes of fish in 2010-2011. The industry contributes nearly INR 200 trillion to the national economy, forming 1.4 percent of national gross domestic product (GDP and 5.4 percent of Agricultural GDP. At present, almost 84 percent of the total inland fish production, in the country is contributed by freshwater aquaculture amounting to 3.9 million tonnes in 2008-09. Further, the potential of the vast freshwater resources covering 6.7 million hectare is yet to be fully realized. The freshwater aquaculture which began as small scale activity of stocking ponds with fish seed collected from riverine sources during early fifties in rural Bengal has now transformed into a major economic activity in almost all states. There is a further need to make the sector more vibrant so as to achieve the predicted target of 15 kg per capita fish availability in the country by 2030.

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

    International Nuclear Information System (INIS)

    Park, Hyun Je; Han, Eunah; Lee, Won Chan; Kwak, Jung Hyun; Kim, Hyung Chul; Park, Mi Seon; Kang, Chang-Keun

    2015-01-01

    Highlights: • A pilot system for the integrated multi-trophic aquaculture was installed. • The black rockfish, sea cucumber, oyster, and macroalgae were co-cultured. • Co-cultured sea cucumber at the IMTA site assimilated aquaculture wastes. • Fish cage-waste contribution to food web in/around the IMTA system was minor. • The sea cucumber was identified as an extractive species of fish cage wastes. - Abstract: To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ 13 C and δ 15 N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment

  8. ASSESSMENT OF ODOUR EMISSIONS FROM AN OPEN BIOFILTER

    Directory of Open Access Journals (Sweden)

    Marlon Brancher

    2014-12-01

    Full Text Available Odour annoyances are considered a major cause of public complaints to regulatory agencies regarding air quality and represent a growing social problem, especially in industrialized countries. In view of the need to diagnose odour sources for control and mitigation of possible impacts on communities, was assessed, through a case study, the odorous emissions from an open biofilter. The equipment was responsible for gas treatment generated in the wastewater plant treatment of a textile industry. Sampling was conducted in the inlet duct of the biofilter using direct sampling and on the emission surface (output using a hood (VDI 3477:2004. Samples were stored in plastic bags manufactured in polyvinyl fluoride (Tedlar® and transported to the laboratory, where the odour concentration (in UO m-3 was determined based on the dynamic olfactometry dilution procedure (EN 13725:2003. To calculate the odour emission rate (OER (in UO h-1, the volumetric flow rate (in m3 h-1 was measured in the inlet duct of the biofilter. The values obtained for the efficiency and the OER were 98.7 % and 0.34 x 106 UO h-1, respectively. Comparing the efficiency value with the criterion established by Article 12 of Resolution SEMA No 054:2006 (State of Paraná, Brazil, adopted as reference, the biofiltration system meets the minimum efficiency rating of 85 % required in removing odour.

  9. 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.

  10. The role of infectious disease impact in informing decision-making for animal health management in aquaculture systems in Bangladesh.

    Science.gov (United States)

    Garza, Maria; Mohan, Chadag Vishnumurthy; Rahman, Meezanur; Wieland, Barbara; Häsler, Barbara

    2018-03-20

    The aquaculture sector in Bangladesh is an important employer and a significant source of foreign exchange. In addition, it contributes significantly to food security due to the role of fish in peoples' diets, the most important source of protein and micronutrients. However, infectious diseases represent an important barrier to sector development due to economic losses and vulnerability of smallholders. The aim of this study was to gain an overview of the impact of infectious diseases in the aquaculture sector, and to assess the usefulness and use of impact studies in decision making for animal health management and biosecurity governance in Bangladesh. A review of scientific and grey literature on infectious disease impact in different aquaculture systems was conducted and their methodologies and findings summarised. Subsequently, interviews with 28 stakeholders from the private and public sector were conducted to enquire about decision-making structures in animal health management. The data were analysed using the framework method to allow the development of themes, by using the information, experiences and opinions inductively obtained from interviewees, deductively through the reviewed literature. Results showed a substantial socio-economic impact of infectious diseases. The numerous stakeholders involved in the decision-making process explained that key barriers to effective aquaculture health management were insufficient resources to investigate and tackle infectious aquatic animal diseases, a dearth of legislation and capacity for disease surveillance, a reliance on reactive response, and a lack of impact and evidence-based approaches for prioritising problem-solving, commonly based on anecdotal evidence. Furthermore, communication among the multiple stakeholders involved was reported to be weak. This complex situation requires a multi-level response, which should span from strengthening the knowledge of farmers and professionals in the field to the

  11. Water quality and emergy evaluation of two freshwater aquacultural systems for eutrophic water in the Controlling by Biological Chains

    Science.gov (United States)

    Xi, L. M.; Liu, C. Q.; Liu, D. F.; Huang, W. L.; Sun, Y.

    2017-08-01

    According to the ecological restoration theory, this experiment establishes aquaculture systems controlled by biological chains in both Xiaoxidian area and Dujiadian area of Baiyangdian Lake separately in order to improve the environment and bring economic benefits. The appearance of Emergy Theory provides a new method for the quantitative analysis of ecological economic system. Based on the analysis of Emergy Theory, this thesis compares the eco-economic systems under different polyculture models between Xiaoxidian area and Dujiadian area. The result demonstrates that Xiaoxidian ecological system is of high Emergy Transformity with higher emergy output and economic income per unit area compared with Dujiadian area. While Dujiadian area has higher Emergy Yield Rate and lower Environment Load Rate. So Dujiadian area is more sustainable due to the overload non-renewable energy of Xiaoxidian area devoted by human. Therefore, it will be better if we adjust and optimize the management of aquaculture system in Xiaoxidian area in order to find a stable equilibrium point between environmental sustainability and economic benefits.

  12. 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

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

    Science.gov (United States)

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

    2013-05-01

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

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

    Science.gov (United States)

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

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-02-15

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

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

    Directory of Open Access Journals (Sweden)

    Serbulov Alexey

    2012-01-01

    Full Text Available This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

  17. Integrated multi-trophic aquaculture (combined production of fish, mussels and seaweed)

    DEFF Research Database (Denmark)

    Holdt, Susan Løvstad; Silva Marinho, Goncalo; Angelidaki, Irini

    2014-01-01

    The Danish marine aquaculture has, despite the huge potential, only been slowly increasing the last 25 years because of the imposed limits to the nitrogen (N) released to the environment. Mussels, seaweed and other organisms have been successfully tested as biofilters in integrated multi-trophic ......The Danish marine aquaculture has, despite the huge potential, only been slowly increasing the last 25 years because of the imposed limits to the nitrogen (N) released to the environment. Mussels, seaweed and other organisms have been successfully tested as biofilters in integrated multi......, mineral and vitamin content and profiles were monitored to evaluate the nutritional value and harvest time of the seaweed biomass. Sugarkelp showed to be efficient for bioremediation of nitrogen, with environmental and potentially economic benefits (e.g. waste water management and for production...

  18. The effect of recirculating aquaculture systems on the concentrations of heavy metals in culture water and tissues of Nile tilapia Oreochromis niloticus

    NARCIS (Netherlands)

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

    2011-01-01

    To date, farming fish in recirculating aquaculture systems (RAS) is one of the most environmentally friendly ways of producing fish. However, with the trend towards intensification, and consequently decrease in water exchange rates, these systems may accumulate substances, such as heavy metals, in

  19. EFEKTIVITAS SISTEM BIOFILTER AEROB DALAM MENURUNKAN KADAR AMONIA PADA AIR LIMBAH

    Directory of Open Access Journals (Sweden)

    Ni Made Indra Wahyuni

    2015-06-01

    Full Text Available The increasingpopulationand activity of the Balinese people can increase the amount of waste as a byproduct of community activities. The presence of the metabolites in wastewater as ammonia is toxic to aquatic organisms. Application aerobic biofilter system can be used as an attempt to reduce levels of ammonia. In the aerobic biofilter, contact between the gravel media with microorganisms that form biofilmsare able to accelerate the degradation of organic matter and nitrification processes. The aims of this research are to determine the best consortium of activated sludge to reduce ammonia levels by aerobic biofilter system and to determine the effectivity of aerobic biofilter system. The first stage of this research were seeding of activated sludge from three sources are Wastewater Treatment Plan (WWTP of Suwung Denpasar, WWTP of Wangaya Hospital and WWTP of Bali Tourism Development Corporation (BTDC Nusa Dua Bali, for six days. This research was done by measuring Volatile Suspended Solid (VSS value that showed the growth rate of biomass in activated sludge. The second stage wereapplication of activated sludges and control in aerobic biofilter to reduce ammonia levels, for five days. This study used a Completely Randomized Design with four treatments and three repetitions. The results showed that the best activated sludge obtained from WWTP of Suwung Denpasar indicated by the highest biomass growth (VSS value of 2396.6 mg/L and was able to reduce ammonia up to 0.78 mg/ L. The effectivity of aerobic biofilter system with activated sludge from WWTP of Suwung Denpasar achieve effectivity of treatment process up to 92.20 % and have been able to pass the effectivity of quality standards (90% during five days of processing. The effectivity levels was the highest compared to control and activated sludgetreatments.

  20. Development of a novel biofilter for aerobic biodegradation of volatile organic compounds (VOCs)

    International Nuclear Information System (INIS)

    Govind, R.; Utgikar, V.; Shan, Y.; Zhao, Wang; Sayles, G.D.; Bishop, D.F.; Safferman, S.I.

    1992-01-01

    In recent years, the emission into the atmosphere of volatile organic compounds (VOCs) has undergone increased regulation by EPA, OSHA and other government agencies due to potential human health hazards. The sources of these VOCs include releases during industrial production and use, from contaminated wastewaters in collection systems and treatment plants, and from hazardous wastes in landfills and contaminated ground water. Conventional methods for treating VOC emissions include adsorption on solids, absorption in solvents, incineration and catalytic oxidation. One alternative to these conventional treatment methods is the biological destruction of the VOCs in gas phase biofilters. This method has the advantage of pollution destruction (as compared to transfer to another medium) at lower operation and maintenance costs. The biofilter method also can be combined with various stripping or vapor extraction separation processes which effectively transfer VOCs from liquid or solid matrices into the gas phase entering biofilters

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

    Directory of Open Access Journals (Sweden)

    Abdullahi Iliyasu

    2016-05-01

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

  2. 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.

  3. Wastewater utilization for poly-β-hydroxybutyrate production by the cyanobacterium Aulosira fertilissima in a recirculatory aquaculture system.

    Science.gov (United States)

    Samantaray, Shilalipi; Nayak, Jitendra Kumar; Mallick, Nirupama

    2011-12-01

    Intensive aquaculture releases large quantities of nutrients into aquatic bodies, which can lead to eutrophication. The objective of this study was the development of a biological recirculatory wastewater treatment system with a diazotrophic cyanobacterium, Aulosira fertilissima, and simultaneous production of valuable product in the form of poly-β-hydroxybutyrate (PHB). To investigate this possible synergy, batch scale tests were conducted under a recirculatory aquaculture system in fiber-reinforced plastic tanks enhanced by several manageable parameters (e.g., sedimentation, inoculum size, depth, turbulence, and light intensity), an adequate combination of which showed better productivity. The dissolved-oxygen level increased in the range of 3.2 to 6.9 mg liter⁻¹ during the culture period. Nutrients such as ammonia, nitrite, and phosphate decreased to as low as zero within 15 days of incubation, indicating the system's bioremediation capability while yielding valuable cyanobacterial biomass for PHB production. Maximum PHB accumulation in A. fertilissima was found in sedimented fish pond discharge at 20-cm culture depth with stirring and an initial inoculum size of 80 mg dry cell weight (dcw) liter⁻¹. Under optimized conditions, the PHB yield was boosted to 92, 89, and 80 g m⁻², respectively for the summer, rainy, and winter seasons. Extrapolation of the result showed that a hectare of A. fertilissima cultivation in fish pond discharge would give an annual harvest of ∼17 tons dry biomass, consisting of 14 tons of PHB with material properties comparable to those of the bacterial polymer, with simultaneous treatment of 32,640 m³ water discharge.

  4. Evaluating the chronic effects of nitrate on the health and performance of post-smolt Atlantic salmon Salmo salar in freshwater recirculation aquaculture systems

    Science.gov (United States)

    Commercial production of Atlantic salmon smolts, post-smolts, and market-size fish using land-based recirculation aquaculture systems (RAS) is expanding. RAS generally provide a nutrient-rich environment in which nitrate accumulates as an end-product of nitrification. An 8-month study was conducted ...

  5. Fillet quality and processing attributes of postsmolt Atlantic salmon, Salmo salar, fed a fishmeal-free diet and a fishmeal-based diet in recirculation aquaculture systems

    Science.gov (United States)

    Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS)....

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  7. Effects of semi-continous peracetic acid dosing on rainbow trout Oncorhynchus mykiss performance, water quality, and off-flavor compounds in recirculation aquaculture systems

    Science.gov (United States)

    Water clarifying and disinfection techniques such as ozonation and ultraviolet irradiation are commonly used in recirculation aquaculture systems (RAS); however, the capital and operating costs of these technologies are expensive. Cost-effective treatment options that maintain fish health and simult...

  8. Flavobacterium branchiophilum and F. succinicans associated with bacterial gill disease in rainbow trout Oncorhynchus mykiss (Walbaum) in water recirculation aquaculture systems

    Science.gov (United States)

    Raised rainbow trout Oncorhynchus mykiss in six replicated water recirculation aquaculture systems (WRAS), and manipulated environmental conditions to promote bacterial gill disease (BGD). For each episode of BGD, gill tissue was sampling from affected fish, unaffected fish within the same WRAS, and...

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

    Science.gov (United States)

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

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

    Science.gov (United States)

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

  11. 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...

  12. Antimicrobial resistance, heavy metal resistance and integron content in bacteria isolated from a South African tilapia aquaculture system.

    Science.gov (United States)

    Chenia, Hafizah Y; Jacobs, Anelet

    2017-11-21

    Antibacterial compounds and metals co-select for antimicrobial resistance when bacteria harbour resistance genes towards both types of compounds, facilitating the proliferation and evolution of antimicrobial and heavy metal resistance. Antimicrobial and heavy metal resistance indices of 42 Gram-negative bacteria from a tilapia aquaculture system were determined to identify possible correlations between these phenotypes. Agar dilution assays were carried out to determine susceptibility to cadmium, copper, lead, mercury, chromate and zinc, while susceptibility to 21 antimicrobial agents was investigated by disk diffusion assays. Presence of merA, the mercury resistance gene, was determined by dot-blot hybridizations and PCR. Association of mercury resistance with integrons and transposon Tn21 was also investigated by PCR. Isolates displayed a high frequency of antimicrobial (erythromycin: 100%; ampicillin: 85%; trimethoprim: 78%) and heavy metal (Zn2+: 95%; Cd2+: 91%) resistance. No correlation was established between heavy metal and multiple antibiotic resistance indices. Significant positive correlations were observed between heavy metal resistance profiles, indices, Cu2+ and Cr3+ resistance with erythromycin resistance. Significant positive correlations were observed between merA (24%)/Tn21 (24%) presence and heavy metal resistance profiles and indices; however, significant negative correlations were obtained between integron-associated qacE∆1 (43%) and sulI (26%) gene presence and heavy metal resistance indices. Heavy metal and antimicrobial agents co-select for resistance, with fish-associated, resistant bacteria demonstrating simultaneous heavy metal resistance. Thus, care should be taken when using anti-fouling heavy metals as feed additives in aquaculture facilities.

  13. Gas treatment in trickle-bed biofilters: biomass, how much is enough?

    Science.gov (United States)

    Alonso, C; Suidan, M T; Sorial, G A; Smith, F L; Biswas, P; Smith, P J; Brenner, R C

    1997-06-20

    The objective of this article is to define and validate a mathematical model that desribes the physical and biological processes occurring in a trickle-bed air biofilter for waste gas treatment. This model considers a two-phase system, quasi-steady-state processes, uniform bacterial population, and one limiting substrate. The variation of the specific surface area with bacterial growth is included in the model, and its effect on the biofilter performance is analyzed. This analysis leads to the conclusion that excessive accumulation of biomass in the reactor has a negative effect on contaminant removal efficiency. To solve this problem, excess biomass is removed via full media fluidization and backwashing of the biofilter. The backwashing technique is also incorporated in the model as a process variable. Experimental data from the biodegradation of toluene in a pilot system with four packed-bed reactors are used to validate the model. Once the model is calibrated with the estimation of the unknown parameters of the system, it is used to simulate the biofilter performance for different operating conditions. Model predictions are found to be in agreement with experimental data. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 54: 583-594, 1997.

  14. High performance of nitrogen and phosphorus removal in an electrolysis-integrated biofilter.

    Science.gov (United States)

    Gao, Y; Xie, Y W; Zhang, Q; Yu, Y X; Yang, L Y

    A novel electrolysis-integrated biofilter system was developed in this study to evaluate the intensified removal of nitrogen and phosphorus from contaminated water. Two laboratory-scale biofilter systems were established, one with electrolysis (E-BF) and one without electrolysis (BF) as control. The dynamics of intensified nitrogen and phosphorus removal and the changes of inflow and outflow water qualities were also evaluated. The total nitrogen (TN) removal rate was 94.4% in our newly developed E-BF, but only 74.7% in the control BF. Ammonium removal rate was up to 95% in biofilters with or without electrolysis integration with an influent ammonium concentration of 40 mg/L, and the accumulation of nitrate and nitrite was much lower in the effluent of E-BF than that of BF. Thus electrolysis plays an important role in TN removal especially the nitrate and nitrite removal. Phosphorus removal was significantly enhanced, exceeding 90% in E-BF by chemical precipitation, physical adsorption, and flocculation of phosphorus because of the in situ formation of ferric ions by the anodizing of sacrificial iron anodes. Results from this study indicate that the electrolysis integrated biofilter is a promising solution for intensified nitrogen and phosphorus removal.

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

    Institute of Scientific and Technical Information of China (English)

    Clark C K Liu

    2013-01-01

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

  16. Disease in marine aquaculture

    Science.gov (United States)

    Sindermann, C. J.

    1984-03-01

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

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

    Directory of Open Access Journals (Sweden)

    G. STEFAN

    2008-10-01

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

  18. 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...

  19. 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

  20. Anaerobe-Aerobe Submerged Biofilter Technology for Domestic Waste Water Treatment; Teknologi Biofilter Anaerob-Aerob Tercelup untuk Pengolahan Air Limbah Domestik

    Energy Technology Data Exchange (ETDEWEB)

    Nusa-Idaman-Said, [The Agency for the Assessment and Application of Technology, Jakarta (Indonesia)

    2000-02-15

    Water pollution in the big cities in Indonesia, especially in DKI Jakarta has shown serious problems. One of the potential sources of water pollution is domestic wastewater that is wastewater from kitchens, laundry, bathing and toilets. These problems have become more serious since the spreads of sewerage systems are still low, so that domestic, institutional and commercial wastewater cause severe water pollution in many rivers or shallow ground water. Bases on the fact that the progress of development of sewerage system is still low, it is important to develop low cost technology for individual house hold or semi communal wastewater treatment such as using anaerobic and aerobic submerged biofilter. This paper describes alternative technology for treatment of household wastewater or organic wastewater using anaerobic and aerobic submerged biofilter. Using this technology can decrease BOD, COD and Suspended Solids (SS) concentration more than 90 %. (author)

  1. GROWTH ENHANCEMENT, SURVIVAL AND DECREASE OF ECTOPARASITIC INFECTIONS IN MASCULINIZED NILE TILAPIA FRY IN A RECIRCULATING AQUACULTURE SYSTEM

    Directory of Open Access Journals (Sweden)

    Isabel Jiménez García

    2012-11-01

    Full Text Available Under lab conditions, tilapia fry at culture densities of 8 fish/L-1 can reach a body weight of 0.5 to 1.0 g after the masculinization phase. In commercial hatcheries, the stocking density is four to six times higher, and consequently the occurrence of ectoparasitic infections also rises. The aim of this study was to examine the growth and survival of masculinized Nile tilapia (Oreochromis niloticus fry in a recirculating aquaculture system (RAS. The fry, which were naturally parasitized by protozoan of the genera Trichodina, Ambiphrya and Chilodonella, weighed 0.013 ± 0.003 g and were reared in replicated tanks (N = 3 during 32 days at density of 18 fish/L-1 in the RAS to maintain good water quality, which was achieved especially during the first 22 days of fish rearing. The infection parameters and growth were monitored twice a week. The final fish weight was 1.17 ± 0. 6 g and survival 99.5%. The most frequent parasites were Trichodina and Gyrodactylus cichlidarum (Monogenea. Although nitrogen compounds increased significantly over the last 10 days of fry rearing, final growth and survival were higher than those reported, additionally, the ectoparasitic infections were relatively low.

  2. 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...

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  4. Inside Story of Gas Processes within Stormwater Biofilters: Does Greenhouse Gas Production Tarnish the Benefits of Nitrogen Removal?

    Science.gov (United States)

    Payne, Emily G I; Pham, Tracey; Cook, Perran L M; Deletic, Ana; Hatt, Belinda E; Fletcher, Tim D

    2017-04-04

    Stormwater biofilters are dynamic environments, supporting diverse processes that act to capture and transform incoming pollutants. However, beneficial water treatment processes can be accompanied by undesirable greenhouse gas production. This study investigated the potential for nitrous oxide (N 2 O) and methane (CH 4 ) generation in dissolved form at the base of laboratory-scale stormwater biofilter columns. The influence of plant presence, species, inflow frequency, and inclusion of a saturated zone and carbon source were studied. Free-draining biofilters remained aerobic with negligible greenhouse gas production during storm events. Designs with a saturated zone were oxygenated at their base by incoming stormwater before anaerobic conditions rapidly re-established, although extended dry periods allowed the reintroduction of oxygen by evapotranspiration. Production of CH 4 and N 2 O in the saturated zone varied significantly in response to plant presence, species, and wetting and drying. Concentrations of N 2 O typically peaked rapidly following stormwater inundation, associated with limited plant root systems and poorer nitrogen removal from biofilter effluent. Production of CH 4 also commenced quickly but continued throughout the anaerobic interevent period and lacked clear relationships with plant characteristics or nitrogen removal performance. Dissolved greenhouse gas concentrations were highly variable, but peak concentrations of N 2 O accounted for nitrogen load. While further work is required to measure surface emissions, the potential for substantial release of N 2 O or CH 4 in biofilter effluent appears relatively low.

  5. Modelling and simulation of a nitrification biofilter for drinking water ...

    African Journals Online (AJOL)

    For the purification of pure and microbiologically safe drinking water, different treatment steps are necessary. One of those steps is the removal of ammonium, which can, e.g. be accomplished through nitrification in a biofilter. In this study, a model for such a nitrifying biofilter was developed and the model was ...

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

    Science.gov (United States)

    Xu, Qiang; Gao, Fei; Yang, Hongsheng

    2016-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Aeknarin Thanakitpairin

    2014-01-01

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

  8. A simple biofilter for treatment of pig slurry in Malaysia.

    Science.gov (United States)

    Sommer, S G; Mathanpaal, G; Dass, G T

    2005-03-01

    On commercial pig production farms in South East (SE) Asia, the liquid effluent is often discharged into rivers. The discharge is a hazard to the environment and to the health of people using water from the river either for consumption or for irrigation. Therefore, a simple percolation biofilter for treatment of the liquid effluent was developed. Pig slurry was treated in test-biofilters packed with different biomass for the purpose of selecting the most efficient material, thereafter the efficiency of the biofilter was examined at farm scale with demo biofilters using the most efficient material. The effect of using "Effective Microorganisms" (EM) added to slurry that was treated with biofilter material mixed with Glenor KR+ was examined. Slurry treatment in the test-biofilters indicated that rice straw was better than coconut husks, wood shavings, rattan strips and oil palm fronds in reducing BOD. Addition of EM and Glenor KR+ to slurry and biofilter material, respectively, had no effect on the temperature of the biofilter material or on the concentrations of organic and inorganic components of the treated slurry. The BOD of slurry treated in test biofilters is reduced to between 80 and 637 mg O2 I(-1) and in the demo biofilter to between 3094 and 3376 mg O2 l(-1). The concentration of BOD in the effluent is related to the BOD in the slurry being treated and the BOD concentration in slurry treated in test biofilters was lower than BOD of slurry treated in demo biofilters. The demo biofilter can reduce BOD to between 52 an 56% of the original value, and TSS, COD (chemical oxygen demand) and ammonium (NH4+) to 41-55% of the original slurry. The treated effluent could not meet the standards for discharge to rivers. The composted biofilter material has a high content of nitrogen and phosphorus; consequently, the fertilizer value of the compost is high. The investments costs were 123 US dollar per SPP which has to be reduced if this method should be a treatment option

  9. Nitrogen Transformation and Microbial Spatial Distribution in Drinking Water Biofilter

    Science.gov (United States)

    Qian, Yongxing; Zhang, Huining; Jin, Huizheng; Wu, Chengxia

    2018-02-01

    Well understanding the rule of nitrogen mutual transformation in biofilters is important for controlling the DBPs formation in the subsequent disinfection process. Ammonia nitrogen removal effect and nitrogen transformation approach in biofilter of drinking water was researched in the study. The biofilter removed ammonia of 48.5% and total phosphorus of 72.3%. And the removal rate of TN, NO3 --N, DON were 37.1%, 33.1%, 46.9%, respectively. Biomass and bioactivity of different depth of the biofilter were determined, too. The overall distribution of biomass showed a decreasing trend from top to bottom. The bioactivity in lower layer gradually increased. Especially the bioactivity of heterotrophic microorganisms showed a gradual increase trend. The amount of the nitrogen loss was 3.06mg/L. Non-nitrification pathway of “nitrogen loss” phenomenon in biofilter might exist assimilation, nitrification and denitrification in autotrophic.

  10. Pengolahan Limbah Rumah Makan dengan Proses Biofilter Aerobik

    Directory of Open Access Journals (Sweden)

    Laily Zoraya Zahra

    2015-03-01

    Full Text Available Berkembangnya rumah makan/restoran yang semakin pesat dapat dipastikan akan turut menambah buangan air limbah domestik dengan kadar organik yang tinggi dalam jumlah yang tidak sedikit yang dibuang ke badan air.Tingginya kadar organik dalam limbah domestik rumah makan akan menyebabkan aroma yang tidak sedap jika tidak ada pengolahan terlebih dahulu, maka pengolahan yang dapat digunakan untuk mengolah air limbah rumah makan tersebut adalah proses biofilter aerobik. Penelitian dilakukan dengan proses biofilter aerobik dengan aliran downflow dan menggunakan sistem intermitten.Variabel dalam penelitian ini adalah media biofilter berupa kerikil dan batu alam serta Hydraulic Retention Time (HRT 8 jam. Parameter pencemar yang diukur efisiensinya adalah BOD, COD, dan TSS. Besarnya penyisihan parameter BOD, COD dan TSS dengan menggunakan biofilter aerob berturut-turut mencapai 94,83%, 92,95%, dan 95%. Reaktor paling baik dalam mengolah air limbah adalah reaktor biofilter dengan media kerikil pada HRT 8 jam.

  11. Soil-biofilters for elimination of xenobiotics from wastewaters

    DEFF Research Database (Denmark)

    Bester, Kai; Schäfer, D; Janzen, N.

    treatment plants are not designed to eliminate these compounds. Even more of these compounds are discharged by storm waters and combined sewer overflows. It is generally suggested that separating sewers into waste water and rainwater systems might help to improve the situation. However in the last few years...... it has been demonstrated, that storm waters can be heavily polluted with biocides, lubricants and PAHs. In this study we investigated the possibilities to eliminate lipophilic fragrances, bactericides, UV blockers, lubricants etc, as well as more hydrophilic organophosphate flame retardants, biocides...... and other components with low cost soil biofilter techniques suited for on-site decentralised treatment of storm waters and combined sewer overflows. On the other hand the same systems and compounds were tested in for polishing treated waste water in respect of further elimination of xenobiotic compounds....

  12. Preliminary acclimation strategies for successful startup in conventional biofilters.

    Science.gov (United States)

    Elías, Ana; Barona, Astrid; Gallastegi, Gorka; Rojo, Naiara; Gurtubay, Luis; Ibarra-Berastegi, Gabriel

    2010-08-01

    The question of how to obtain the best inocula for conventional biofilters arises when an acclimation/adaptation procedure is to be applied. Bearing in mind that no standardized procedure for acclimating inocula exists, certain preliminary strategies for obtaining an active inoculum from wastewater treatment sludge are proposed in this work. Toluene was the contaminant to be degraded. Concerning the prior separation of sludge phases, no obvious advantage was found in separating the supernatant phase of the sludge before acclimation. As far as a continuous or discontinuous acclimation mode is concerned, the latter is recommended for rapidly obtaining acclimated sludge samples by operating the system for no longer than 1 month. The continuous mode rendered similar degradation rates, although it required longer operating time. Nevertheless, the great advantage of the continuous system lay in the absence of daily maintenance and the ready availability of the activated sample.

  13. Resistance and resilience of small-scale recirculating aquaculture systems (RAS) with or without algae to pH perturbation

    Science.gov (United States)

    Giatsis, Christos; Md Yusoff, Fatimah; Verreth, Johan; Verdegem, Marc

    2018-01-01

    The experimental set-up of this study mimicked recirculating aquaculture systems (RAS) where water quality parameters such as dissolved oxygen, pH, temperature, and turbidity were controlled and wastes produced by fish and feeding were converted to inorganic forms. A key process in the RAS was the conversion of ammonia to nitrite and nitrite to nitrate through nitrification. It was hypothesized that algae inclusion in RAS would improve the ammonia removal from the water; thereby improving RAS water quality and stability. To test this hypothesis, the stability of the microbiota community composition in a freshwater RAS with (RAS+A) or without algae (RAS-A) was challenged by introducing an acute pH drop (from pH 7 to 4 during three hours) to the system. Stigeoclonium nanum, a periphytic freshwater microalga was used in this study. No significant effect of the algae presence was found on the resistance to the acute pH drop on ammonia conversion to nitrite and nitrite conversion to nitrate. Also the resilience of the ammonia conversion to the pH drop disruption was not affected by the addition of algae. This could be due to the low biomass of algae achieved in the RAS. However, with regard to the conversion step of nitrite to nitrate, RAS+A was significantly more resilient than RAS-A. In terms of overall bacterial communities, the composition and predictive function of the bacterial communities was significantly different between RAS+A and RAS-A. PMID:29659617

  14. Assessment of yeast as a dietary additive on haematology and water quality of common carp in a recirculating aquaculture system

    Science.gov (United States)

    Goran, Siraj Muhammed Abdulla; Omar, Samad Sofy; Anwer, Ayub Youns

    2017-09-01

    Feeding experiment was accomplished at the Aquaculture unit (Close system), Grdarasha station, Agriculture College, University of Salahaddin, Erbil, Kurdistan Region, to investigate different levels of Aquagrow E (AGEY) brewer's yeast cell Saccharomyces cerevisiae on the haematological and water quality of common carp fingerlings Cyprinus carpio. The basal diet was formulated to contain 34% protein and 10% lipid and the dietary treatments were supplemented with 0.5%, 1% and 1.5% of AGEY diet. A total of 180 Common carp (10.30 ± 0.27 g) fed on experimental diets for 10 weeks. Water quality assessment for well water and pond water for rearing Cyprinus carpio in cage system conducted weekly, while some parameters including pH, EC, water temperature and DO were monitored daily during the entire periods of study. Values of total hardness, alkalinity, ammonia and nitrate for studied water samples were within normal ranges for rearing Cyprinus carpio. Mean concentration of GPT, GOT and Glucose were 104 to 170 U/L, 1371 to 3308 U/L and 34 to 63mg/dl respectively, moreover, highest levels were observed in treatments with higher concentrations of yeast in its food except for blood sugar. Slight variation in lipase enzyme were found between control and treatment groups, while levels of amylase enzyme were increased toward cages with higher levels of yeast until T1 and then decreased toward T3. Total protein levels were increased to toward higher levels of yeast in food of Cyprinus carpio fish. Haematological results showed highest levels of WBC and platelets in treatments cages than control group. Levels of RBCs and hemoglobin were highest in treatment group 1 with 0.5%of yeast than treatments higher yeast concentrations. Significant correlation was found in haematological parameters between control and treatments.

  15. 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), ...

  16. Efficient and economical way of operating a recirculation aquaculture system in an aquaponics farm

    NARCIS (Netherlands)

    Karimanzira, Divas; Keesman, Karel; Kloas, Werner; Baganz, Daniela; Rauschenbach, Thomas

    2017-01-01

    In this article, optimal control methods based on a metabolite-constrained fish growth model are applied to the operation of fish production in an aquaponic system. The system is formulated for the twin objective of fish growth and plant fertilization to maximize the benefits by optimal and

  17. Aquaculture innovation system analysis of transition to sustainable intensification in shrimp farming

    NARCIS (Netherlands)

    Joffre, Olivier M.; Klerkx, Laurens; Khoa, Tran N.D.

    2018-01-01

    The shrimp sector has been one of the fastest growing agri-food systems in the last decades, but its growth has entailed negative social and environmental impacts. Sustainable intensification will require innovation in multiple elements of the shrimp production system and its value chain. We use

  18. 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...

  19. Biopiles and biofilters combined for soil cleanup

    International Nuclear Information System (INIS)

    Lei, J.; Sansregret, J.L.; Cyr, B.

    1994-01-01

    Bioremediation of hydrocarbon-contaminated soils can be completed using a combination of biopile and biofiltration technologies. Target contaminants, such as gasoline, jet fuel, diesel fuel and other petroleum-derived products are removed from the soil by biodegradation and volatilization in the biopile. Air emissions from the biopile containing volatile hydrocarbons are treated subsequently in a biofilter, where the pollutants are degraded and mineralized by heterotrophic aerobic microorganisms. In the biopile process, contaminated soil is excavated and stockpiled in a treatment area. Remediation of the soil relies on microbial degradation and volatilization of hydrocarbons under controlled treatment conditions

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  1. Shrimp-based livelihoods in mangrove silvo-aquaculture farming systems

    NARCIS (Netherlands)

    Bosma, R.H.; Nguyen, T.H.; Siahainenia, A.J.; Tran, H.T.P.; Tran, H.N.

    2016-01-01

    The paper reviews the following three types of mangrove-shrimp systems: (i) integrated with canals between platforms planted with mangrove; (ii) associated having larger areas of water and a large mangrove area; and (iii) separated, with a dyke separating ponds from forest. The variations in shrimp

  2. A hybridized membrane-botanical biofilter for improving air quality in occupied spaces

    Science.gov (United States)

    Llewellyn, David; Darlington, Alan; van Ras, Niels; Kraakman, Bart; Dixon, Mike

    Botanical biofilters have been shown to be effective in improving indoor air quality through the removal of complex mixtures of gaseous contaminants typically found in human-occupied environments. Traditional, botanical biofilters have been comprised of plants rooted into a thin and highly porous synthetic medium that is hung on vertical surfaces. Water flows from the top of the biofilter and air is drawn horizontally through the rooting medium. These botanical biofilters have been successfully marketed in office and institutional settings. They operate efficiently, with adequate contaminant removal and little maintenance for many years. Depending on climate and outdoor air quality, botanical biofiltration can substantially reduce costs associated with ventilation of stale indoor air. However, there are several limitations that continue to inhibit widespread acceptance: 1. Current designs are architecturally limiting and inefficient at capturing ambient light 2. These biofilters can add significant amounts of humidity to an indoor space. This water loss also leads to a rapid accumulation of dissolved salts; reducing biofilter health and performance 3. There is the perception of potentially actively introducing harmful bioaerosols into the air stream 4. Design and practical limitations inhibit the entrance of this technology into the lucrative residential marketplace This paper describes the hybridization of membrane and botanical biofiltration technologies by incorporating a membrane array into the rootzone of a conventional interior planting. This technology has the potential for addressing all of the above limitations, expanding the range of indoor settings where botanical biofiltration can be applied. This technology was developed as the CSA-funded Canadian component an ESA-MAP project entitled: "Biological airfilter for air quality control of life support systems in manned space craft and other closed environments", A0-99-LSS-019. While the project addressed a

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

    Directory of Open Access Journals (Sweden)

    Rana Dinesh Singh

    2015-01-01

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

  4. Anaerobe-Aerobe Submerged Biofilter Technology for Domestic Waste Water Treatment

    International Nuclear Information System (INIS)

    Nusa-Idaman-Said

    2000-01-01

    Water pollution in the big cities in Indonesia, especially in DKI Jakarta has shown serious problems. One of the potential sources of water pollution is domestic wastewater that is wastewater from kitchens, laundry, bathing and toilets. These problems have become more serious since the spreads of sewerage systems are still low, so that domestic, institutional and commercial wastewater cause severe water pollution in many rivers or shallow ground water. Bases on the fact that the progress of development of sewerage system is still low, it is important to develop low cost technology for individual house hold or semi communal wastewater treatment such as using anaerobic and aerobic submerged biofilter. This paper describes alternative technology for treatment of household wastewater or organic wastewater using anaerobic and aerobic submerged biofilter. Using this technology can decrease BOD, COD and Suspended Solids (SS) concentration more than 90 %. (author)

  5. A simple and low-cost recirculating aquaculture system for the production of arapaima juveniles

    OpenAIRE

    Burton, Andrew Mark; Moncayo Calderero, Edwin; Burgos Moran, Ricardo Ernesto; Anastacio Sánchez, Rogelio Lumbes; Avendaño Villamar, Ulises Tiberio; Ortega Torres, Nelson Guillermo

    2016-01-01

    A simple and low-cost recirculating system (RAS) for production of arapaima  (Arapaima gigas) juveniles is described. Twenty arapaima fry (mean 13.0 cm, 12.0 g) were housed in three production tanks and fed a high HUFA diet resulting in 90% of fry successfully progressing to juveniles (mean 17.4 cm long; 40.2 g). The fish were then reared for a further 72 days fed on commercial extruded pellet feed achieving a mean length of 42.6 cm and 656.6 g. The simple and low-cost RAS holds good potentia...

  6. Methanol removal efficiency and bacterial diversity of an activated carbon biofilter.

    Science.gov (United States)

    Babbitt, Callie W; Pacheco, Adriana; Lindner, Angela S

    2009-12-01

    Motivated by the need to establish an economical and environmentally friendly methanol control technology for the pulp and paper industry, a bench-scale activated carbon biofiltration system was developed. This system was evaluated for its performance in removing methanol from an artificially contaminated air stream and characterized for its bacterial diversity over time, under varied methanol loading rates, and in different spatial regions of the filter. The biofilter system, composed of a novel packing mixture, provided an excellent support for growth and activity of methanol-degrading bacteria, resulting in approximately 100% methanol removal efficiency for loading rates of 1-17 g/m(3) packing/h, when operated both with and without inoculum containing enriched methanol-degrading bacteria. Although bacterial diversity and abundance varied over the length of the biofilter, the populations present rapidly formed a stable community that was maintained over the entire 138-day operation of the system and through variable operating conditions, as observed by PCR-DGGE methods that targeted all bacteria as well as specific methanol-oxidizing microorganisms. Phylogenetic analysis of bands excised and sequenced from DGGE gels indicated that the biofilter system supported a diverse community of methanol-degrading bacteria, with high similarity to species in the genera Methylophilus (beta-proteobacteria), Hyphomicrobium and Methylocella (both alpha-proteobacteria).

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    The calanoid copepod Acartia tonsa (Dana) is one of the most promising copepod species for marine larviculture. This species has a wide tolerance to temperature and salinity, small size, can produce resting eggs. All their nauplii, copepodites and adults can be use as excellent feeds for marine...... capacity. A. tonsa fed the unicellular algae Rhodomonas baltica were registered for four weeks in triplicate 50 L tanks in each system. Water quality parameters were recorded daily for temperature, oxygen, pH, salinity, particles and every five days for nitrogenous waste and bacteria through...... the similar survival, growth, and reproduction, yet the nauplii developed into copepodites faster in RAS (110h) compared to FTAS (158h). This can be an indication for the potential for culturing or maintaining A. tonsa nauplii and early copepodite stages at higher densities before feeding larvae of marine...

  8. Structure of the bacterial community in a biofilter during dimethyl sulfide (DMS) removal processes.

    Science.gov (United States)

    Chung, Ying-Chien; Cheng, Chiu-Yu; Chen, Tzu-Yu; Hsu, Jo-Shan; Kui, Chun-Chi

    2010-09-01

    We report here both the successful treatment of DMS in a biofilter and the dynamic changes that occur in the composition of the bacterial community of the biofilter during this process. Denaturing gradient gel electrophoresis of eubacterial 16S rDNA samples taken from packing material at different DMS removal stages revealed 11 distinct bands. Phylogenetic analysis showed that the sequences of these bands were closest to sequences of species of the Proteobacteria, Firmicutes, and Actinobacteria. The specific occurrence of these bacterial species varied mainly with DMS load, but it was also affected by the addition of glucose and by ambient temperature. Based on the characteristics of the identified species, the system is conducive for such processes as sulfur oxidation, sulfate reduction, carbon oxidation, and fermentation. The strains identified in this study are potential candidates for purifying waste gas effluents containing DMS gas. Copyright 2010 Elsevier Ltd. All rights reserved.

  9. Evaluation of the Efficiency of a Biofilter System’s Phenol Removal From Wastewater

    Directory of Open Access Journals (Sweden)

    Reza Shokoohi

    2016-06-01

    Full Text Available Phenol is a toxic hydrocarbon that has been found in the wastewater of several industries, including the petroleum and petrochemical industries. The discharge of untreated wastewater from these industries causes environmental pollution, especially in water. The aim of this study was to evaluate the efficiency of phenol removal from wastewater using a biofiltration system. In this experimental study, a cylindrical plexiglass biofilter reactor with an effective volume of 12 liters was used. A total of 30 pcs of plastic grid discs were placed inside the reactor by plastic pipes to maintain the biofilm media in the reactor. The microorganisms used in this study were obtained from the biological sludge of a municipal wastewater treatment plant. The reproduction and adaptation of the microorganisms to 500 mg/L of phenol lasted three months. The effects of pH, phenol, nitrogen, phosphorus, glucose concentration, and hydraulic retention time on the biofilter system’s performance was evaluated. The results of this study showed that in optimal conditions, this system can reduce the phenol concentration from 500 mg/L to zero within about 4 hr. Maximum efficiency occurred in pH = 7, and the proper COD/N/P ratio was 100/10/2, respectively. In general, this biofilter system is capable of removing 500 mg/L of phenol concentrations and an organic load of 4 - 4.5 kg COD/m3.d within 4 - 5 hr. with high efficiency.

  10. 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.

  11. Microbial Biotreatment of Actual Textile Wastewater in a Continuous Sequential Rice Husk Biofilter and the Microbial Community Involved

    OpenAIRE

    Forss, J?rgen; Lindh, Markus V.; Pinhassi, Jarone; Welander, Ulrika

    2017-01-01

    Textile dying processes often pollute wastewater with recalcitrant azo and anthraquinone dyes. Yet, there is little development of effective and affordable degradation systems for textile wastewater applicable in countries where water technologies remain poor. We determined biodegradation of actual textile wastewater in biofilters containing rice husks by spectrophotometry and liquid chromatography mass spectrometry. The indigenous microflora from the rice husks consistently performed >90% de...

  12. Nitrification performance and robustness of fixed and moving bed biofilters having identical carrier elements

    DEFF Research Database (Denmark)

    Pedersen, Lars-Flemming; Oosterveld, Remko; Pedersen, Per Bovbjerg

    2015-01-01

    media with asurface specific area to volume ratio of 750 m2/m3. Total ammonia nitrogen (TAN) and apparent nitriteremoval rates were measured during identical steady-state conditions and during a water treatmentevent where 50 mg/l hydrogen peroxide was applied. FB biofilters were found to perform equal...... particularly in the MB biofilters. The findingsindicate FB biofilters to be more resistant against the sanitizer applied, due to increased organic matterin the biofilters compared to MB biofilters. Aspects of the experimental setup are discussed in relation toother studies and commercial biofilter operations....

  13. 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...

  14. 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

  15. Potential of Biofilters for Treatment of De-Icing Chemicals

    OpenAIRE

    Raspati, Gema Sakti; Lindseth, Hanna Kristine; Muthanna, Tone Merete; Azrague, Kamal

    2018-01-01

    Organic de-icing chemicals, such as propylene glycol and potassium formate, cause environmental degradation in receiving water if left untreated, due to the high organic load resulting in oxygen depletion. Biofilters are commonly used for the treatment of biodegradable organic carbon in water treatment. This study investigated the potential for using biofilters for treating organic de-icing compounds. Lab-scale adsorption tests using filter media made of crushed clay (Filtralite) and granular...

  16. Antimicrobial media for passive removal of pathogen by stormwater biofilters

    OpenAIRE

    Li, Yali

    2017-01-01

    Stormwater biofilters (designed primarily for nutrient and metal removal) are gaining popularity globally for the treatment of urban stormwater runoff. However, their reported faecal indicator removal efficiency varies from several log to net leaching, and the effluent concentrations rarely meet the requirements for stormwater harvesting. In order to improve the stormwater biofilter design for reliable pathogen treatment, research in three Stages is therefore conducted systematically: identif...

  17. 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.

  18. The Usage of Geographical Information System in the Selection of Floating Cages Location for Aquaculture at Prigi Bay, Trenggalek Regency, East Java

    Science.gov (United States)

    Armono, H. D.; Mahaputra, B. G.; Zikra, M.

    2018-03-01

    Floating cages is one of the methods of fish farming (aqua culture) that can be developed at rivers, lakes or seas. To determine a proper location for floating cages, there are some requirements that need to be fulfilled to maintain sustainibility of floating cages. Those requirements are the quality of the environment. This paper will discuss the selection of best location for aquaculture activities using Weighted Overlay method in the Geographical Information System, based on the the concentration of chlorophyll-a, sea surface temperature presented by Aqua MODIS Level 1b satellite images. The satellite data will be associated with the measured field data on March and October 2016. The study take place on Prigi Bay, at Trenggalek Regency, East Java. Based on spatial analysis in the Geographical Information System, the Prigi bay generally suitable for aquaculture activities using floating net cages. The result of Weighted Overlay combinations in both periods showed a mean score of 2.18 of 3 where 8.33 km2 (23.13% of the water area) considered as "very suitable" and 27.67 km2 (76.87% of water area) considered "suitable".

  19. A geographical information system for the management of the aquaculture data in the Adriatic Sea – the Strengthening of Centres for Aquaculture Production and Safety surveillance in the Adriatic countries experience: Present capabilities, tools and functions

    Directory of Open Access Journals (Sweden)

    Susanna Tora

    2017-11-01

    Full Text Available The European Commission (EC regulation no. 854/2004 requires a systematic monitoring of chemical and microbiological contaminants in live bivalve molluscs, live echinoderms, live tunicates and live marine gastropods for human consumption through surveillance plans to be implemented in all European Union (EU countries.A consortium of five Adriatic countries was set up in the framework of the Instrument of Pre-accession Assistance Adriatic Cross-border Cooperation Programme (IPA Adriatic CBC 2007- 2013 with the aim of collecting data and distribute information on harvesting and production in mollusc areas. A web-based geographical information system (GIS application was developed to support the partners to manage data and to make these data available to final users, policy makers and to risk assessors. The GIS for the Strengthening of Centres for Aquaculture Production and Safety surveillance in the Adriatic countries (CAPS2 is divided into two levels, the national and the supranational one, and it distributes spatial and epidemiological information coming from various data acquisition and management sites. The great innovation is the possibility for each country to use online drawing, modifying and change of the geographic areas according to national surveillance needs. Currently it hosts data coming from about 230 production and relay areas with more than 29,478 laboratory tests performed on collected samples since August 2014. Data collected are used by each national competent authority to classify production or relay areas according to the EC regulation mentioned and to conduct risk assessment studies to evaluate the level of consumers’ exposure to contaminants in the consumption of bivalve mollusc products.

  20. Deodorising biofilters: reliable systems for meeting the new odour prevention requirements; Biofiltros de desodorizacion: sistemas fiables para afrontar las nuevas exigencias en prevencion de olores

    Energy Technology Data Exchange (ETDEWEB)

    Echtner, E.; Bieger, K.

    2002-07-01

    Bad smell that inevitably are connected with waste water treatment are becoming first range problems in the frame of European legislation and jurisprudence. Efficient deodorization systems are necessary to prevent sanctions and quarrels with administration and neighbours. Biological deodorization filters are a viable, proved, efficient and economic alternative to classical wastes gas treatment systems. With and appropriate design retention yields of>99% can be achieved. International studies show an increasing acceptance of these filters in waste water treatment plants. Indications about the most important characteristics in the design of the equipment's are given. (Author) 12 refs.

  1. 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...

  2. 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.

  3. 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…

  4. 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...

  5. 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....

  6. 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,…

  7. Determination of the efficiency of sawdust and coco fiber used as Biofilter for pollutant removal for the treatment of wastewater

    Directory of Open Access Journals (Sweden)

    Jimmy Vicente Reyes

    2016-09-01

    Full Text Available Water is a resource used by mankind for industrial and domestic needs, which once used, is discharged into the public sewer system or septic tanks. This project proposes an ecological alternative for the treatment of wastewater from domestic use named Biofilter, which is built of living material (worms and inert material (chip and gravel, which filters the wastewater; the biological filter has shown high efficiency in the removal of organic matter and pathogens. The field work was carried out with experimental biological filters, to ascertain the best composition of inert material, different variants were used. Two experimental Biofilters, one using sawdust and the other coco fiber were used in the treatment of domestic wastewater; treated samples from each reactor were subjected to laboratory analysis. The analysis and interpretation of results showed that the Biofilter using sawdust removed 53.53 % of pollutants and is outside the required norm for wastewater treatment and the Biofilter using coco fiber removed 82.37 % of contaminants and is within the Environmental Quality Norm and Effluent Discharge: Water Resource.

  8. Removal of nutrients in denitrification system using coconut coir fibre for the biological treatment of aquaculture wastewater.

    Science.gov (United States)

    Manoj, Valsa Remony; Vasudevan, Namasivayam

    2012-03-01

    Ideal bacterial support medium for fixed film denitrification processes/bioreactors must be inexpensive, durable and possess large surface area with sufficient porosity. The present study has been focussed on removing nitrate nitrogen at two different nitrate nitrogen loading rates (60 (NLR I) and 120 (NLR II) mg l(-1)) from simulated aquaculture wastewater. Coconut coir fibre and a commercially available synthetic reticulated plastic media (Fujino Spirals) were used as packing medium in two independent upflow anaerobic packed bed column reactors. Removal of nitrate nitrogen was studied in correlation with other nutrients (COD, TKN, dissolved orthophosphate). Maximum removal of 97% at NLR-I and 99% at NLR - II of nitrate nitrogen was observed in with either media. Greater consistency in the case of COD removal of upto 81% was observed at NLR II where coconut coir was used as support medium compared to 72% COD removal by Fujino Spirals. The results observed indicate that the organic support medium is just as efficient in nitrate nitrogen removal as conventionally used synthetic support medium. The study is important as it specifically focuses on denitrification of aquaculture wastewater using cheaper organic support medium in anoxic bioreactors for the removal of nitrate nitrogen; which is seldom addressed as a significant problem.

  9. Effect of nitrate on sulfur transformations in sulfidogenic sludge of a marine aquaculture biofilter

    DEFF Research Database (Denmark)

    Schwermer, Carsten Ulrich; Ferdelman, Timothy G.; Stief, Peter

    2010-01-01

    to 35mmol L-1 day-1), indicating that the main source of sulfide in the sludge was not SO42- reduction, but desulfuration during the decomposition of organic matter. Although NO3- inhibited SO42- reduction, but not desulfuration, the primary NO3- mitigation effect was the onset of NO3--mediated sulfide...... oxidation (up to 75 mmolL-1 day-1), partially to elemental sulfur (S0). Above NO3- concentrations of 0.6mM in the bulk water, the net sulfide production and oxidation zones were moved deeper into flocs and sludge cores, which effectively prevented sulfide from entering the water column. However, the sulfide...

  10. The design of trickling biological periwinkle shells filter for closed ...

    African Journals Online (AJOL)

    ... and economics of biofilter in reirculating aquaculture systems using local material ... The system with the designed biofilter served as the treatment system, while the ... The selected system recirculation rate was 10 times per hour, while the ...

  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. Environmental comparison of intensive and integrated agriculture-aquaculture systems for striped catfish production in the Mekong Delta, Vietnam, based on two existing case studies using life cycle assessment

    NARCIS (Netherlands)

    Kluts, I.N.; Potting, J.M.B.; Bosma, R.H.; Phong, L.T.; Udo, H.M.J.

    2012-01-01

    Vietnam is the largest producer for the export of striped catfish. Traditionally striped catfish production in the Mekong Delta took place in integrated agriculture–aquaculture systems, but has shifted recently to intensive systems to meet increasing export demands. A recent study quantified the

  13. Evaluation of a rainbow trout (Oncorhynchus mikyss culture water recirculating system

    Directory of Open Access Journals (Sweden)

    Iván Sánchez O.

    2014-09-01

    Full Text Available Objective. To evaluate a water recirculation system for rainbow trout fish cultures at the recirculating laboratory of the Aquaculture Engineering Production Program of University of Nariño. Materials and Methods. 324 rainbow trout (Oncorhynchus mikyss fries were cultured in 12 plastic tanks with a capacity of 250 L in an aquaculture recirculating system the treatment system of which was made up by a conventional sedimentation tank, a fixed stand upflow biofilter with recycled PVC tube pieces and a natural degassing system; the sedimentation unit effluent was pumped up to a reservoir tank using a 2 HP centrifugal pump after being subject to gravity through the biofilter and to be then distributed to the 12 culture units to which a constant amount of air from a blower was injected. Results. The water treatment system removed 31% of total suspended solids, 9.5% of total ammonia nitrogen, and increased dissolved oxygen to the final effluent in 6.5%. An increase of 305% in biomass was calculated during 75 days, the mortality percentage registered throughout the study period was 4.9%. Conclusions. The water treatment system maintained the physicochemical water quality parameters within the values recommended for the species. The increase in weight and size, food conversion, mortality and biomass production reported normal values for rainbow trout fish culture in recirculating systems.

  14. Economical assessment of the design, construction and operation of open-bed biofilters for waste gas treatment.

    Science.gov (United States)

    Prado, O J; Gabriel, D; Lafuente, J

    2009-06-01

    A protocol was developed with the purpose of assessing the main costs implied in the set-up, operation and maintenance of a waste gas-treating conventional biofilter. The main operating parameters considered in the protocol were the empty bed residence time and the gas flow rate. A wide variety of investment and operating costs were considered. In order to check its reliability, the protocol was applied to a number of scenarios, with biofilter volumes ranging from 8.3 to 4000 m(3). Results show that total annualized costs were between 20,000 and 220,000 euro/year and directly dependent, among other factors, on the size of the system. Total investment and operating costs for average-size compost biofilters were around 60,000 euro and 20,000 euro/year, respectively, which are concordant with actual costs. Also, a sensitivity analysis was performed in order to assess the relative influence of a series of selected costs. Results prove that operating costs are those that influence the total annual costs to a higher extent. Also, packing material replacement costs contribute significantly to the total yearly costs in biofilters with a volume higher than 800 m(3). Among operating costs, the electricity consumption is the main influencing factor in biofilters with a gas flow rate above 50,000 m(3)/h, while labor costs are critical at lower gas flow rates. In addition, the use of a variety of packing materials commonly employed in biofiltration was assessed. According to the results obtained, special attention should be paid to the packing material selected, as it is the main parameter influencing the medium replacement costs, and one of the main factors affecting investment costs.

  15. Nitrogen utilization and biomass yield in trickle bed air biofilters.

    Science.gov (United States)

    Kim, Daekeun; Sorial, George A

    2010-10-15

    Nitrogen utilization and subsequent biomass yield were investigated in four independent lab-scale trickle bed air biofilters (TBABs) fed with different VOCs substrate. The VOCs considered were two aromatic (toluene, styrene) and two oxygenated (methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK)). Long-term observations of TBABs performances show that more nitrogen was required to sustain high VOC removal, but the one fed with a high loading of VOC utilized much more nitrogen for sustaining biomass yield. The ratio N(consumption)/N(growth) was an effective indicator in evaluating nitrogen utilization in the system. Substrate VOC availability in the system was significant in determining nitrogen utilization and biomass yield. VOC substrate availability in the TBAB system was effectively identified by using maximum practical concentrations in the biofilm. Biomass yield coefficient, which was driven from the regression analysis between CO(2) production rate and substrate consumption rate, was effective in evaluating the TBAB performance with respect to nitrogen utilization and VOC removal. Biomass yield coefficients (g biomass/g substrate, dry weight basis) were observed to be 0.668, 0.642, 0.737, and 0.939 for toluene, styrene, MEK, and MIBK, respectively. 2010 Elsevier B.V. All rights reserved.

  16. Research on the Aerodynamic Resistance of Trickle Biofilter

    Directory of Open Access Journals (Sweden)

    Alvydas Zagorskis

    2011-12-01

    Full Text Available A four – section trickle biofilter was constructed for experimental research. The filter was filled with the packing material of artificial origin. The material consists of plastic balls having a large surface area. The dependence of biofilter aerodynamic resistance on supply air flow rate and the number of filter sections was determined. The aerodynamic resistance of the biofilter was measured in two cases. In the first case, the packing material of the filter was dry, whereas in the second case it was wet. The experimental research determined that an increase in the air flow rate from 0.043 m/s to 0.076 m/s causes an increase in biofilter aerodynamic resistance from 30.5 to 62.5 Pa after measuring four layers of dry packing material. In case of wet packing material, biofilter aerodynamic resistance after measuring four layers of plastic balls increases from 42.1 to 90.4 Pa.Article in Lithuanian

  17. Balancing and dynamic behaviour of a biofilter plant for complete cleaning of municipal sewage; Bilanzierung und dynamisches Verhalten einer Biofilteranlage zur Vollreinigung von kommunalem Abwasser

    Energy Technology Data Exchange (ETDEWEB)

    Dickgreber, M.; Luebbecke, S. [Preussag Wassertechnik GmbH, Bremen (Germany)

    1999-07-01

    Where municipal sewage treatment plants need to be extended or enlarged, biofilter systems represent an economical alternative. They can be used both for supplementary residual elimination purposes and to treat complete sewage streams. For a biofilter system for complete cleaning of sewage employing the DENIPOR trademark -NCS process which has been in operation since 1996 (2*500 population value), studies in process dynamics are carried out and a complete balance is set up. (orig.) [German] Biofilter stellen bei notwendigen Erweiterungen und Ausbaumassnahmen von kommunalen Klaeranlagen eine wirtschaftliche Alternative dar. Sie koennen fuer weitergehende Restreinigungsaufgaben und zur Vollstrombehandlung eingesetzt werden. An einer seit 1996 in Betrieb befindlichen Biofilteranlage zur Vollreinigung von kommunalem Abwasser nach dem DENIPOR {sup trademark} -NCS Verfahren (2*500EW) werden Untersuchungen zur Prozessdynamik sowie eine vollstaendige Bilanzierung durchgefuehrt. (orig.)

  18. 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.

  19. 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...

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

    Science.gov (United States)

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

    2016-01-01

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

  1. The effects of long-term 20 mg/L carbon dioxide exposure on the health and performance of Atlantic salmon Salmo salar post-smolts in water recirculation aquaculture systems

    Science.gov (United States)

    Previous research and experience has linked elevated dissolved carbon dioxide (CO2) to reduced growth performance, poor feed conversion, and a variety of health issues in farm-raised fish, including Atlantic salmon Salmo salar. Supplemental control measures in water recirculation aquaculture systems...

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

    Science.gov (United States)

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

  3. 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...

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

    Science.gov (United States)

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

    2015-10-01

    The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences ( P important quality attributes of Atlantic salmon.

  5. THE USE OF BIOFILTERS FOR DEODORISATION OF THE NOXIOUS GASES

    Directory of Open Access Journals (Sweden)

    Monika Wierzbińska

    2015-01-01

    Full Text Available One of the methods of deodorization of noxious gases is biofiltration. This method consists of pollutants biodegradation by using micro-organisms, what leads to the formation of nontoxic and innoxious compounds. In comparison with conventional techniques, bio-filtration requires lower investments and exploitation costs, moreover it is nature friendly. This technique is still developing. Scientists have carried out research on the optimization of biofiltration process, biofilters and selecting parameters of purified gases or improving the method of efficiency. However, industrial application of biofilters is still difficult for many reasons. In this paper we present the mechanism of biofiltration process, the parameters and conditions which have to be fulfilled by purified gases, installation structure for gases biofiltration, application field of this method and specific example of exploited biofilters, including practical operational guidelines.

  6. 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 ...

  7. Biofiltration of Chloroform in a Trickle Bed Air Biofilter Under ...

    Science.gov (United States)

    In this paper, the application of biofiltration is investigated for controlled removal of gas phase chloroform through cometabolic degradation with ethanol. A trickle bed air biofilter (TBAB) operated under acidic pH 4 is subjected to aerobic biodegradation of chloroform and ethanol. The TBAB is composed of pelleted diatomaceous earth filter media inoculated with filamentous fungi species, which served as the principle biodegrading microorganism. The removal efficiencies of 5 ppmv of chloroform mixed with different ratios of ethanol as cometabolite (25, 50, 100, 150, and 200 ppmv) ranged between 69.9 and 80.9%. The removal efficiency, reaction rate kinetics, and the elimination capacity increased proportionately with an increase in the cometabolite concentration. The carbon recovery from the TBAB amounted to 69.6% of the total carbon input. It is postulated that the remaining carbon contributed to excess biomass yield within the system. Biomass control strategies such as starvation and stagnation were employed at different phases of the experiment. The chloroform removal kinetics provided a maximum reaction rate constant of 0.0018 s−1. The highest ratio of chemical oxygen demand (COD)removal/nitrogenutilization was observed at 14.5. This study provides significant evidence that the biodegradation of a highly chlorinated methane can be favored by cometabolism in a fungi-based TBAB. Chloroform is volatile hazardous chemical emitted from publicly owned treatment

  8. 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...

  9. Performance of a sand filter in removal of micro-algae from seawater in aquaculture production systems.

    Science.gov (United States)

    Sabiri, N E; Castaing, J B; Massé, A; Jaouen, P

    2012-01-01

    In this study, a sand filter was used to remove micro-algae from seawater feeding aquaculture ponds. A lab-scale sand filter was used to filter 30,000 cells/mL of Heterocapsa triquetra suspension, a non-toxic micro-alga that has morphological and dimensional (15-20 microm) similarities with Alexandrium sp., one of the smallest toxic micro-algae in seawater. Removal efficiency and capture mechanisms for a fixed superficial velocity (3.5 m/h) were evaluated in relation to size distribution and mean diameter of the sand. Various sands (average diameter ranging between 200 microm and 600 microm) were characterized and used as porous media. The structural parameters of the fixed beds were evaluated for each medium using experimental measurements of pressure drop as a function of superficial velocity over a range of Reynolds numbers covering Darcy's regime and the inertial regime. For a filtration cycle of six hours, the best efficiency (E = 90%) was obtained with the following sand characteristics: sieved sand with a range of grain diameter of 100 and 300 microm and a mean grain diameter equal to 256 microm. Results obtained show the influence of the size distribution of sand on the quality of retention of the micro-algae studied.

  10. 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.

  11. 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)

  12. 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.

  13. 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.

  14. 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...

  15. 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…

  16. 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

  17. 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.

  18. 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...

  19. 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...

  20. Elimination of butanal from odorous air by a labscale biofilter

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Vriens, L.; Verachtert, H.

    1991-01-01

    Butanal was chosen as a model compound for testing the performance of biofilters. It's a member of an important class of odour compounds released by waste water treatment plants of animal rendering and food processing industry. The influence of nutrient supplementation has been investigated using

  1. Combined denitrification and phosphorus removal in a biofilter

    DEFF Research Database (Denmark)

    Falkentoft, Christina Maria; Harremoes, Poul; Mosbæk, Hans

    2000-01-01

    A lab-scale biofilter was run continuously for 11/2 years for combined denitrification and phosphorus removal. Alternation between anaerobic and anoxic (nitrate) conditions was used to obtain an enriched culture of denitrifying, phosphate accumulating organisms. Batch experiments were performed...

  2. Start-up of a drinking water biofilter

    DEFF Research Database (Denmark)

    Ramsay, Loren; Søborg, Ditte; Breda, Inês Lousinha Ribeiro

    When virgin filter media is placed in drinking water biofilters, a start-up period of some months typically ensues. During this period, the necessary inorganic coating and bacterial community are established on the filter medium, after which the treated water complies with drinking water criteria...

  3. ERA-AQUA version 2.0, technical description and manual : a decision support system for the environmental risk assessment of veterinary medicines applied in pond AQUAculture

    NARCIS (Netherlands)

    Rico Artero, A.; Geng, Y.; Focks, A.; Brink, van den P.J.

    2012-01-01

    Veterinary medicinal products are applied in aquaculture production for treating and preventing diseases in the cultured species. Veterinary medicines may enter the environment by effluent discharges, posing a potential risk for surrounding aquatic ecosystems. Furthermore, human health and the trade

  4. 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

  5. Effects of periods of nonuse and fluctuating ammonia concentration on biofilter performance.

    Science.gov (United States)

    Chen, Ying-Xu; Yin, Jun; Wang, Kai-Xiong; Fang, Shi

    2004-01-01

    A systematic study on the transient behavior of odor treatment using biofilters is described. The biofilters were exposed to variations in contaminant loading and periods of nonuse. Two bench-scale biofilters with different filter media were used. Mixtures of compost/perlite (5:1) and dry sludge/granular active carbon (5:1) were used as filter media. Ammonia (NH3), one of the main malodorous gases, was used as the target compound. The response of each biofilter to variations in contaminant mass loading, periodic nonuse, water content, and inlet concentration pulse was studied. The nonuse period comprised of two stages: the "idle phase" when no air was passing through the biofilters, and the "no-contaminant-loading phase" when only humidified air was passing through the biofilters. Concentration spike was applied to study the effects of shock loading on the biofilter performance. Biofilters responded effectively to NH3 concentration variations and shock loading by rapidly recovering to the original removal rates within 6-12h. The results indicated re-acclimation times ranged from several hours to longer than a day. Longer idle phase produced longer re-acclimation periods than periods of no contaminant loading. When the media was dried during the biofiltration process, elimination capacity dropped accordingly for both biofilters. After 24 h of drying, the biofilter experiment could be restarted and run for a few days for recovering.

  6. Long-term operational studies of lab-scale pumice-woodchip packed stormwater biofilters.

    Science.gov (United States)

    Cheng, Jing; Yuan, Qingke; Kim, Youngchul

    2017-06-13

    The performance of three pumice-woodchip packed stormwater biofilter (PWSWBF) systems with three packing volume ratios of pumice to woodchip (1:2, 1:1 and 2:1) were compared. The results show that the PWSWBF system packed with a lower percentage of woodchip attained a higher removal efficiency of TCOD, TN, NH 4 -N and TP, whereas all three systems completely removed nitrate. The highest removal efficiencies for TCOD, TN, NH 4 -N, NO 3 -N and TP were 95%, 70%, 86%, 100% and 100%, respectively. In the biofilter with a lower percentage of woodchip, the pollutants that get removed through aerobic biological processes were removed more significantly, which is attributed to less oxygen depletion via woodchip decomposition, which is common under wet conditions. Nitrate was significantly removed via denitrification in all three systems, indicating that the woodchip that occupied one-third of the main media was sufficient for denitrification, and also that the oxygen condition inside the column was proper for denitrification to proceed. A smaller amount of woodchip as the packing material also mitigated the adverse effect of the release of organics from the media during the initial period. In addition, the system showed very good buffering capacity, in that the outflow pH was constant within the optimal range for microorganism growth.

  7. Chronic exposure to low environmental concentrations and legal aquaculture doses of antibiotics cause systemic adverse effects in Nile tilapia and provoke differential human health risk.

    Science.gov (United States)

    Limbu, Samwel M; Zhou, Li; Sun, Sheng-Xiang; Zhang, Mei-Ling; Du, Zhen-Yu

    2018-06-01

    Antibiotics used globally to treat human and animal diseases exist ubiquitously in the environment at low doses because of misuse, overdose and poor absorption after ingestion, coupled with their high-water solubility and degradation resistance. However, the systemic chronic effects of exposure to low environmental concentrations of antibiotics (LECAs) and legal aquaculture doses of antibiotics (LADAs) in fish and their human health risk are currently unknown. To investigate the in vivo chronic effects of exposure to LECAs and LADAs using oxytetracycline (OTC) and sulfamethoxazole (SMZ) in Nile tilapia (Oreochromis niloticus) and their human health risk. Twenty O. niloticus weighing 27.73 ± 0.81 g were exposed to water containing LECAs (OTC at 420 ng/L and SMZ at 260 ng/L) and diets supplemented with LADAs (OTC 80 mg/kg/day and SMZ 100 mg/kg/day) for twelve weeks. General physiological functions, metabolic activities, intestinal and hepatic health were systemically evaluated. The possible human health risks of the consumption of the experimental Nile tilapia fillets in adults and children were assessed by using risk quotient. After exposure, we observed retarded growth performance accompanied by reduced nutrients digestibility, feed efficiency, organ indices, and lipid body composition in treated fish. Antibiotics distorted intestinal morphological features subsequently induced microbiota dysbiosis and suppressed intestinal tight junction proteins. Exposure of fish to LECAs and LADAs induced oxidative stress, suppressed innate immunity, stimulated inflammatory and detoxification responses, concomitantly inhibited antioxidant capacity and caused lipid peroxidation in intestine and liver organs. Both LECAs and LADAs enhanced gluconeogenesis, inhibited lipogenesis and fatty acid beta oxidation in intestine and liver organs. The exposure of fish to LECAs and LADAs induced anaerobic glycolytic pathway and affected intestinal fat catabolism in intestine

  8. A two-stage combined trickle bed reactor/biofilter for treatment of styrene/acetone vapor mixtures.

    Science.gov (United States)

    Vanek, Tomas; Halecky, Martin; Paca, Jan; Zapotocky, Lubos; Gelbicova, Tereza; Vadkertiova, Renata; Kozliak, Evguenii; Jones, Kim

    2015-01-01

    Performance of a two-stage biofiltration system was investigated for removal of styrene-acetone mixtures. High steady-state acetone loadings (above C(in)(Ac) = 0.5 g.m(-3) corresponding to the loadings > 34.5 g.m(-3).h(-1)) resulted in a significant inhibition of the system's performance in both acetone and styrene removal. This inhibition was shown to result from the acetone accumulation within the upstream trickle-bed bioreactor (TBR) circulating mineral medium, which was observed by direct chromatographic measurements. Placing a biofilter (BF) downstream to this TBR overcomes the inhibition as long as the biofilter has a sufficient bed height. A different kind of inhibition of styrene biodegradation was observed within the biofilter at very high acetone loadings (above C(in)(Ac) = 1.1 g.m(-3) or 76 g.m(-3).h(-1) loading). In addition to steady-state measurements, dynamic tests confirmed that the reactor overloading can be readily overcome, once the accumulated acetone in the TBR fluids is degraded. No sizable metabolite accumulation in the medium was observed for either TBR or BF. Analyses of the biodegradation activities of microbial isolates from the biofilm corroborated the trends observed for the two-stage biofiltration system, particularly the occurrence of an inhibition threshold by excess acetone.

  9. Microbial Biotreatment of Actual Textile Wastewater in a Continuous Sequential Rice Husk Biofilter and the Microbial Community Involved

    Science.gov (United States)

    Lindh, Markus V.; Pinhassi, Jarone; Welander, Ulrika

    2017-01-01

    Textile dying processes often pollute wastewater with recalcitrant azo and anthraquinone dyes. Yet, there is little development of effective and affordable degradation systems for textile wastewater applicable in countries where water technologies remain poor. We determined biodegradation of actual textile wastewater in biofilters containing rice husks by spectrophotometry and liquid chromatography mass spectrometry. The indigenous microflora from the rice husks consistently performed >90% decolorization at a hydraulic retention time of 67 h. Analysis of microbial community composition of bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) gene fragments in the biofilters revealed a bacterial consortium known to carry azoreductase genes, such as Dysgonomonas, and Pseudomonas and the presence of fungal phylotypes such as Gibberella and Fusarium. Our findings emphasize that rice husk biofilters support a microbial community of both bacteria and fungi with key features for biodegradation of actual textile wastewater. These results suggest that microbial processes can substantially contribute to efficient and reliable degradation of actual textile wastewater. Thus, development of biodegradation systems holds promise for application of affordable wastewater treatment in polluted environments. PMID:28114377

  10. Microbial Biotreatment of Actual Textile Wastewater in a Continuous Sequential Rice Husk Biofilter and the Microbial Community Involved.

    Directory of Open Access Journals (Sweden)

    Jörgen Forss

    Full Text Available Textile dying processes often pollute wastewater with recalcitrant azo and anthraquinone dyes. Yet, there is little development of effective and affordable degradation systems for textile wastewater applicable in countries where water technologies remain poor. We determined biodegradation of actual textile wastewater in biofilters containing rice husks by spectrophotometry and liquid chromatography mass spectrometry. The indigenous microflora from the rice husks consistently performed >90% decolorization at a hydraulic retention time of 67 h. Analysis of microbial community composition of bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS gene fragments in the biofilters revealed a bacterial consortium known to carry azoreductase genes, such as Dysgonomonas, and Pseudomonas and the presence of fungal phylotypes such as Gibberella and Fusarium. Our findings emphasize that rice husk biofilters support a microbial community of both bacteria and fungi with key features for biodegradation of actual textile wastewater. These results suggest that microbial processes can substantially contribute to efficient and reliable degradation of actual textile wastewater. Thus, development of biodegradation systems holds promise for application of affordable wastewater treatment in polluted environments.

  11. 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.

  12. 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.)

  13. Which species? A decision-support tool to guide plant selection in stormwater biofilters

    Science.gov (United States)

    Payne, Emily G. I.; Pham, Tracey; Deletic, Ana; Hatt, Belinda E.; Cook, Perran L. M.; Fletcher, Tim D.

    2018-03-01

    Plant species are diverse in form, function and environmental response. This provides enormous potential for designing nature-based stormwater treatment technologies, such as biofiltration systems. However, species can vary dramatically in their pollutant-removal performance, particularly for nitrogen removal. Currently, there is a lack of information on how to efficiently select from the vast palette of species. This study aimed to identify plant traits beneficial to performance and create a decision-support tool to screen species for further testing. A laboratory experiment using 220 biofilter columns paired plant morphological characteristics with nitrogen removal and water loss for 20 Australian native species and two lawn grasses. Testing was undertaken during wet and dry conditions, for two biofilter designs (saturated zone and free-draining). An extensive root system and high total biomass were critical to the effective removal of total nitrogen (TN) and nitrate (NO3-), driven by high nitrogen assimilation. The same characteristics were key to performance under dry conditions, and were associated with high water use for Australian native plants; linking assimilation and transpiration. The decision-support tool uses these scientific relationships and readily-available information to identify the morphology, natural distribution and stress tolerances likely to be good predictors of plant nitrogen and water uptake.

  14. Biological elimination of volatile, organic compounds from waste gases in a biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G.; Chabot, J.C.; Caron, J.J.; Heitz, M. [Universite de Sherbrooke, Sherbrooke, PQ (Canada). Dept. de Genie Chimique

    1998-01-01

    A great deal of research has been directed towards the problem of reduction and control of volatile organic compounds (VOCs). The aim of this research is to find a process that is both efficient and inexpensive in comparison with traditional air treatment technologies. The biofilter used, a one stage system, 2 m in height, is an aerobic system for waste gases containing VOC`s using the degradation properties of microbial flora (assorted cultures of Bacillus, Micrococcus, Acinetobacter and yeast). In this process, polluted gas diffuses across a filter bed into which a microbial culture has previously been introduced. Peat is the medium of choice for inoculation with microorganisms because of its adsorption and absorption properties, ability to retain moisture, and buffering capacity. Furthermore, the peat utilized is spherical in shape; thus, it is possible to avoid problems related to compacting. The objective of this study was to eliminate VOCs emitted from a rotogravure process. The team was able to achieve promising results from biofiltration of two types of VOCs (a mixed solvent containing isopropyl acetate and 1-nitropropane, and the solvent: 1-nitropropane). The results obtained indicate that the elimination of nitropropane and the mixed solvent in the biofilter are considered to follow zero-order kinetics with reaction rate limitation and diffusion rate limitation, respectively. 8 refs., 5 figs.

  15. 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...

  16. Performance of low pH biofilters treating a paint solvent mixture: Continuous and intermittent loading

    International Nuclear Information System (INIS)

    Qi Bing; Moe, William M.

    2006-01-01

    Two biofilters packed with a reticulated polyurethane foam medium were inoculated with a compost-derived enrichment culture grown under acidic conditions (pH 3.0) and then operated over a period lasting 63 days. Both biofilters were supplied with a humidified gas stream containing a five-component mixture of acetone, methyl ethyl ketone, toluene, ethylbenzene, and p-xylene at a total VOC loading rate 80.3 g m -3 h -1 to simulate treatment of air emissions resulting from manufacture of reformulated paint. One biofilter was operated under continuous loading conditions and the other received intermittent loading with contaminants supplied only 8 h/day. Nutrient solution with pH 3.0 was supplied approximately once per week to provide nitrogen and other nutrients. Data are presented which demonstrate that undefined mixed cultures acclimated at low pH can successfully treat paint solvent mixtures in biofilters. The biofilter receiving continuous loading reached high overall removal efficiency (greater than 90% overall removal) 3 weeks after startup, and performance increased over time reaching overall removal in the range of 97-99% after 50 days. Performance of the intermittently loaded biofilter developed more slowly, requiring 6 weeks to stabilize at an overall removal efficiency in excess of 90%. In both biofilters, ketone components were more rapidly degraded than aromatic components, and removal of aromatic compounds was somewhat unstable even after 2 months of biofilter operation. Scanning electron microscopy (SEM) revealed that fungi dominated the microbial populations in both biofilters

  17. Production of Mycosporine-Like Amino Acids from Gracilaria vermiculophylla (Rhodophyta) Cultured Through One Year in an Integrated Multi-trophic Aquaculture (IMTA) System.

    Science.gov (United States)

    Barceló-Villalobos, Marta; Figueroa, Félix L; Korbee, Nathalie; Álvarez-Gómez, Félix; Abreu, Maria H

    2017-06-01

    This study evaluates the production of biomass and mycosporine-like amino acids (MAAs) throughout the year in Gracilaria vermiculophylla (Rhodophyta) collected in Ria de Aveiro (Portugal). The algae were grown in outdoor tanks in seawater with the addition of fishpond effluents under two different water flows (100 and 200 L h -1 ) in an integrated multi-trophic aquaculture (IMTA) system (tanks 1200 L; 1.5 m 2 ) and different algal densities (3, 5, and 7 kg m -2 ). MAA content in IMTA seaweeds was significantly affected by the interaction of time and stocking density, but not by the water flow. The highest MAA content was observed in April (about 3.13 mg g -1 DW) followed by May (1.79 mg g -1 DW). Seaweed biomass productivity was higher in May (372.06 g DW m -2  week -1 ) than in April (353.40 g DW m -2  week -1 ). Four MAAs were identified by HPLC and electrospray ionization mass spectrometry (ESI-MS) in G. vermiculophylla: Porphyra-334, Shinorine, Palythine and Asterina-330. The highest levels of Porphyra-334 and Shinorine were reached from November to January and the Palythine + Asterina-330 from April to August. Taking into account the average biomass and MAA production of G. vermiculophylla growing in this IMTA system (8.56 g of MAA in 18 m 2 culture along 8 months; 35.5% produced in April), a total amount of 71.33 g MAA year -1 could be produced in this system by scaling up to 100 m 2 . MAAs could be further used as photoprotector and antioxidant compounds in cosmetic products.

  18. Potential of Biofilters for Treatment of De-Icing Chemicals

    Directory of Open Access Journals (Sweden)

    Gema Sakti Raspati

    2018-05-01

    Full Text Available Organic de-icing chemicals, such as propylene glycol and potassium formate, cause environmental degradation in receiving water if left untreated, due to the high organic load resulting in oxygen depletion. Biofilters are commonly used for the treatment of biodegradable organic carbon in water treatment. This study investigated the potential for using biofilters for treating organic de-icing compounds. Lab-scale adsorption tests using filter media made of crushed clay (Filtralite and granular activated carbon were conducted. Further, a column filtration experiment testing two different crushed clay size ranges was carried out investigating the effect of filter media depth, nutrient addition, and filtration rate. The surrogate parameter used to monitor the removal of de-icing chemicals was dissolved organic carbon (DOC. The adsorption test showed no significant adsorption of DOC was observed. The column test showed that the most active separation occurred in the first ~20 cm of the filter depth. This was confirmed by results from (1 water quality analysis (i.e., DOC removal and adenosine tri-phosphate (ATP measurement; and (2 calculations based on a filtration performance analysis (Iwasaki model and filter hydraulic evaluation (Lindquist diagram. The results showed that, for the highest C:N:P ratio tested (molar ratio of 24:7:1, 50–60% DOC removal was achieved. The addition of nutrients was found to be important for determining the biofilter performance.

  19. 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...

  20. 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

  1. Commercial African Catfish (Clarias gariepinus Recirculating Aquaculture Systems: Assessment of Element and Energy Pathways with Special Focus on the Phosphorus Cycle

    Directory of Open Access Journals (Sweden)

    Sebastian Marcus Strauch

    2018-05-01

    Full Text Available The reuse of effluent waters and sediments from African catfish (Clarias gariepinus recirculation aquaculture systems requires a deeper understanding of the nutrient and energy flows and material pathways. Three semi-commercial systems, differing in stocking density, were sampled for nutritive and pollutant elements of the input- (tap water, feed and output pathways (fillet, carcass, process water, sediments by ICP-OES/MS and calorimetry. Highly water-soluble elements, e.g., potassium, accumulated in the water, whereas iron, copper, chromium and uranium where found in the solids. Feed derived phosphorous was accounted for, 58.3–64.2% inside the fish, 9.7–19.3% in sediments, and small amounts 9.6–15.5% in the process waters. A total of 7.1–9.9% of the feed accumulated as dry matter in the sediments, comprising 5.5–8.7% total organic carbon and 3.7–5.2% nitrogen. A total of 44.5–47.1% of the feed energy was found in the fish and 5.7–7.7% in the sediments. For reuse of water and nutrients in hydroponics, the macro-nutrients potassium, nitrate, phosphorus and the micro-nutrient iron were deficient when compared with generalized recommendations for plant nutrition. Low energy contents and C/N-ratio restrict the solely use of African catfish solids for biogas production or vermiculture. Using the outputs both for biogas supplement and general fertilizer in aquaponics farming (s.l. (combined with additional nutrients appears possible.

  2. 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.

  3. 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

  4. Impact of temperature on ammonium and nitrite removal rates in RAS moving bed biofilters

    DEFF Research Database (Denmark)

    Kinyage, John Peter Hewa; Pedersen, Lars-Flemming

    2016-01-01

    The impact of temperature on bacterial processes is well known; however temperature related data on nitrification rates in aquaculture systems are fragmented and compiled from different studies. We sought to determine ammonium and nitrite removal kinetics over a temperature range from 6 to 36 °C...

  5. Effect of culture density on production characteristics and body composition of market size cobia reared from juveniles in recirculating aquaculture systems

    Science.gov (United States)

    Interest regarding 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 the principal...

  6. Supplementation of lactobacilli improves growth, regulates microbiota composition and suppresses skeletal anomalies in juvenile pike-perch (Sander lucioperca) reared in recirculating aquaculture system (RAS): A pilot study.

    Science.gov (United States)

    Ljubobratovic, Uros; Kosanovic, Dejana; Vukotic, Goran; Molnar, Zsuzsanna; Stanisavljevic, Nemanja; Ristovic, Tijana; Peter, Geza; Lukic, Jovanka; Jeney, Galina

    2017-12-01

    This research aimed to test the effects of lactobacilli, applied to cultured pike-perch, either through hydrolyzed OTOHIME fish diet, or through Artemia nauplii, on fish growth, microbiota balance and skeletal development. On the 12th Day Post Hatching (DPH) fish were divided into following treatment groups: two groups received the combination of OTOHIME and nauplii enriched either with Lactobacillus paracasei BGHN14+Lactobacillus rhamnosus BGT10 or with Lactobacillus reuteri BGGO6-55+Lactobacillus salivarius BGHO1, and one group received OTOHIME hydrolyzed by BGHN14+BGT10 and non-enriched nauplii. Control group received non-enriched nauplii and non-hydrolyzed OTOHIME. The treatment lasted 14days and fish were sacrificed on the 26th DPH for the assessment of digestive enzyme activity and microbiota composition. Individual total lengths and individual body weights were recorded at the end of the treatments, on the 26th DPH, and also on the 45th DPH, in parallel with the evaluation of skeletal deformities and fish survival. Our results indicated positive effect of Artemia enriched with BGGO6-55+BGHO1 on fish growth, skeletal development and trypsin to chymotrypsin activity ratio (T/C), as an indicator of protein digestibility. Hydrolysis of OTOHIME was also associated with better skeletal development, higher T/C values and lower levels of Aeromonas and Mycobacterium spp., which are important fish pathogens. Though additional testing in larger cohort studies is needed, these observations are promising in terms of usage of probiotics for improved environmentally friendly production of pike-perch in Recirculating Aquaculture System (RAS). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Microbial Community in a Biofilter for Removal of Low Load Nitrobenzene Waste Gas.

    Directory of Open Access Journals (Sweden)

    Jian Zhai

    Full Text Available To improve biofilter performance, the microbial community of a biofilter must be clearly defined. In this study, the performance of a lab-scale polyurethane biofilter for treating waste gas with low loads of nitrobenzene (NB (< 20 g m-3 h-1 was investigated when using different empty bed residence times (EBRT (64, 55.4 and 34 s, respectively. In addition, the variations of the bacterial community in the biofilm on the longitudinal distribution of the biofilters were analysed by using Illumina MiSeq high-throughput sequencing. The results showed that NB waste gas was successfully degraded in the biofilter. High-throughput sequencing data suggested that the phylum Actinobacteria and genus Rhodococcus played important roles in the degradation of NB. The variations of the microbial community were attributed to the different intermediate degradation products of NB in each layer. The strains identified in this study were potential candidates for purifying waste gas effluents containing NB.

  8. 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 ...

  9. Methodologies for pre-validation of biofilters and wetlands for stormwater treatment.

    Directory of Open Access Journals (Sweden)

    Kefeng Zhang

    Full Text Available Water Sensitive Urban Design (WSUD systems are frequently used as part of a stormwater harvesting treatment trains (e.g. biofilters (bio-retentions and rain-gardens and wetlands. However, validation frameworks for such systems do not exist, limiting their adoption for end-uses such as drinking water. The first stage in the validation framework is pre-validation, which prepares information for further validation monitoring.A pre-validation roadmap, consisting of five steps, is suggested in this paper. Detailed methods for investigating target micropollutants in stormwater, and determining challenge conditions for biofilters and wetlands, are provided.A literature review was undertaken to identify and quantify micropollutants in stormwater. MUSIC V5.1 was utilized to simulate the behaviour of the systems based on 30-year rainfall data in three distinct climate zones; outputs were evaluated to identify the threshold of operational variables, including length of dry periods (LDPs and volume of water treated per event.The paper highlights that a number of micropollutants were found in stormwater at levels above various worldwide drinking water guidelines (eight pesticides, benzene, benzo(apyrene, pentachlorophenol, di-(2-ethylhexyl-phthalate and a total of polychlorinated biphenyls. The 95th percentile LDPs was exponentially related to system design area while the 5th percentile length of dry periods remained within short durations (i.e. 2-8 hours. 95th percentile volume of water treated per event was exponentially related to system design area as a percentage of an impervious catchment area.The out-comings of this study show that pre-validation could be completed through a roadmap consisting of a series of steps; this will help in the validation of stormwater treatment systems.

  10. Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

    Science.gov (United States)

    Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

    2012-06-01

    Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4

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

    Science.gov (United States)

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

  12. Microbial diversity in different compartments of an aquaponics system.

    Science.gov (United States)

    Schmautz, Zala; Graber, Andreas; Jaenicke, Sebastian; Goesmann, Alexander; Junge, Ranka; Smits, Theo H M

    2017-05-01

    Aquaponics is a solution for sustainable production of fish and plants in a single semi-closed system, where nutrient-rich water from the aquaculture provides nutrients for plant growth. We examined the microbial communities within an experimental aquaponics system. Whereas the fish feces contained a separate community dominated by bacteria of the genus Cetobacterium, the samples from plant roots, biofilter, and periphyton were more similar to each other, while the communities were more diverse. Detailed examination of the data gave the first indications to functional groups of organisms in the different compartments of the aquaponic system. As other nitrifiers other than members of the genus Nitrospira were only present at low numbers, it was anticipated that Nitrospirae may perform the nitrification process in the biofilm.

  13. 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....

  14. 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 ...

  15. 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.

  16. Liquid Film Diffusion on Reaction Rate in Submerged Biofilters

    DEFF Research Database (Denmark)

    Christiansen, Pia; Hollesen, Line; Harremoës, Poul

    1995-01-01

    Experiments were carried out in order to investigate the influence of liquid film diffusion on reaction rate in a submerged biofilter with denitrification and in order to compare with a theoretical study of the mass transfer coefficient. The experiments were carried out with varied flow, identified...... by the empty bed velocity of inflow and recirculation, respectively 1.3, 2.8, 5.6 and 10.9 m/h. The filter material consisted of 3 mm biostyren spheres. The results indicate that the influence of liquid film diffusion on reaction rate can be ignored....

  17. Biostimulation strategies to enhance manganese removal in drinking water biofilters

    DEFF Research Database (Denmark)

    Breda, Inês Lousinha Ribeiro; Ramsay, Loren; Søborg, Ditte

    to national drinking water criteria. The period during which virgin filter media matures into a fully functional biofilter is designated as the start-up period. The duration of a start-up for efficient manganese removal varies from weeks to more than a year. The aim of this study was to investigate...... growth and activity of specific bacteria. Biostimulation of virgin media to enhance initial manganese removal using different amendments strategies is possible especially in the early stages of filter development whereas autocatalytic processes appear to become dominant with time. The complex...

  18. The influence of temperature and salt on metal and sediment removal in stormwater biofilters.

    Science.gov (United States)

    Søberg, Laila C; Viklander, Maria; Blecken, Godecke-Tobias

    2014-01-01

    Stormwater biofilters are used to treat stormwater runoff. In countries with cold winter climates, biofilters are subject to low temperatures which, in some cases, are combined with potentially high salt concentrations from road de-icing, potentially affecting the biofilter's performance. Since stormwater biofilters have been developed without consideration of their critical winter use, a laboratory study was carried out to evaluate the performance of stormwater biofilters subjected to low and high temperatures, with and without salt. Both factors and their interaction had a significant effect on outflow concentrations and removal percentages. Salt had a negative impact on outflow concentrations, causing lower removal percentages for (especially dissolved) metals, this impact being most pronounced for Cu and Pb. The unrealistic combination of salt with high temperature seemed to further amplify the negative impacts of salt despite the fact that temperature alone did not cause significant differences in outflow concentrations and removal percentages. Still, biofilters showed the ability to treat stormwater efficiently under the simulated winter conditions; outflow concentrations for total metals as a minimum met the class 4 threshold value defined in the Swedish freshwater quality guidelines, while inflow concentrations clearly exceeded the threshold value for class 5. The relatively coarse filter material (which is recommended to facilitate infiltration during winter) did not seem to exacerbate biofilter performance.

  19. 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 ...

  20. 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...

  1. Biodegradation of mono-chlorobenzene by using a trickle bed air biofilter (TBAB).

    Science.gov (United States)

    Mathur, Anil K; Majumder, C B; Singh, Dhananjay; Bala, Shashi

    2010-07-01

    In the present study, performance of the trickle bed airbiofilter (TBAB) for treating mono-chlorobenzene (MCB) was evaluated for various influent volatile organic compound (VOC) loadings using coal and mixed consortium of activated sludge as the packing material. Microbial acclimation to MCB was achieved by exposing the system continuously for 31 d to an average inlet MCB concentration of 0.688 g m(-3) at an empty bed residence time (EBRT) of 188 s. The TBAB achieved maximum removal efficiency of 87% at an EBRT of 188 s for an inlet concentration of 0.681 g m(-3), which is quite significance than the values reported in the literature. Elimination capacities of MCB increased with an increase of the influent VOC loading, but an opposite trend was observed for the removal efficiency The maximum elimination capacity of the biofilter was 110.75 g m(-3) hr(-1) at an inlet MCB concentration of 1.47 g m(-3). The effect of starvation on the TBAB was also studied. After starvation, the TBAB lost its ability to degrade MCB initially However the biofilter recovered very quickly Evaluation of the concentration profile along the bed height indicated that the bottom section of TBAB has the best performance for all concentrations. By using Wani's method of macrokinetic determination based on simple Monod kinetics, the maximum removal rate of MCB, r(max) and saturation constant K(m) was to be found as 1.304 g m(-3)s(-1) and 113.446 g m(-3), respectively.

  2. Dimethylamine biodegradation by mixed culture enriched from drinking water biofilter.

    Science.gov (United States)

    Liao, Xiaobin; Chen, Chao; Zhang, Jingxu; Dai, Yu; Zhang, Xiaojian; Xie, Shuguang

    2015-01-01

    Dimethylamine (DMA) is one of the important precursors of drinking water disinfection by-product N-nitrosodimethylamine (NDMA). Reduction of DMA to minimize the formation of carcinogenic NDMA in drinking water is of practical importance. Biodegradation plays a major role in elimination of DMA pollution in the environment, yet information on DMA removal by drinking water biofilter is still lacking. In this study, microcosms with different treatments were constructed to investigate the potential of DMA removal by a mixed culture enriched from a drinking water biofilter and the effects of carbon and nitrogen sources. DMA could be quickly mineralized by the enrichment culture. Amendment of a carbon source, instead of a nitrogen source, had a profound impact on DMA removal. A shift in bacterial community structure was observed with DMA biodegradation, affected by carbon and nitrogen sources. Proteobacteria was the predominant phylum group in DMA-degrading microcosms. Microorganisms from a variety of bacterial genera might be responsible for the rapid DMA mineralization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  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. 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.

  5. Investigating the influence of nitrate nitrogen on post-smolt Atlantic salmon Salmo salar reproductive physiology in water recirculation aquaculture systems

    Science.gov (United States)

    Good, Christopher; Davidson, John; Iwanowicz, Luke R.; Meyer, Michael T.; Dietze, Julie E.; Kolpin, Dana W.; Marancik, David; Birkett, Jill; Williams, Christina; Summerfelt, Steven T.

    2017-01-01

    A major issue affecting land-based, closed containment Atlantic salmon Salmo salar growout production in water recirculation aquaculture systems (RAS) is precocious male maturation, which can negatively impact factors such as feed conversion, fillet yield, and product quality. Along with other water quality parameters, elevated nitrate nitrogen (NO3-N) has been shown to influence the reproductive development and endogenous sex steroid production in a number of aquatic animal species, including Atlantic salmon. We sought to determine whether elevated NO3-N in RAS can influence early maturation in post-smolt Atlantic salmon in an 8-month trial in replicated freshwater RAS. Post-smolt Atlantic salmon (102 ± 1 g) were stocked into six RAS, with three RAS randomly selected for dosing with high NO3-N (99 ± 1 mg/L) and three RAS set for low NO3-N (10 ± 0 mg/L). At 2-, 4-, 6-, and 8-months post-stocking, 5 fish were randomly sampled from each RAS, gonadosomatic index(GSI) data were collected, and plasma was sampled for 11-ketotestosterone(11-KT) quantification. At 4- and 8-months post-stocking, samples of culture tank and spring water (used as “makeup” or replacement water) were collected and tested for a suite of 42 hormonally active compounds using liquid chromatography/mass spectrometry, as well as for estrogenicity using the bioluminescent yeast estrogen screen (BLYES) reporter system. Finally, at 8-months post-stocking 8–9 salmon were sampled from each RAS for blood gas and chemistry analyses, and multiple organ tissues were sampled for histopathology evaluation. Overall, sexually mature males were highly prevalent in both NO3-N treatment groups by study’s end, and there did not appear to be an effect of NO3-N on male maturation prevalence based on grilse identification, GSI, and 11-KT results, indicating that other culture parameters likely instigated early maturation. No important differences were noted between treatment groups for

  6. Efficient Total Nitrogen Removal in an Ammonia Gas Biofilter through High-Rate OLAND

    DEFF Research Database (Denmark)

    De Clippeleir, Haydée; Courtens, Emilie; Mosquera, Mariela

    2012-01-01

    Ammonia gas is conventionally treated in nitrifying biofilters; however, addition of organic carbon to perform post-denitrification is required to obtain total nitrogen removal. Oxygen-limited autotrophic nitrification/denitrification (OLAND), applied in full-scale for wastewater treatment, can...... offer a cost-effective alternative for gas treatment. In this study, the OLAND application thus was broadened toward ammonia loaded gaseous streams. A down flow, oxygen-saturated biofilter (height of 1.5 m; diameter of 0.11 m) was fed with an ammonia gas stream (248 ± 10 ppmv) at a loading rate of 0...... at water flow rates of 1.3 ± 0.4 m3 m–2 biofilter section d–1. Profile measurements revealed that 91% of the total nitrogen activity was taking place in the top 36% of the filter. This study demonstrated for the first time highly effective and sustainable autotrophic ammonia removal in a gas biofilter...

  7. Styrene removal from wate gas by the fungus Exophiala Jeanselmei in a biofilter

    NARCIS (Netherlands)

    Cox, Hubertus Henricus Jacobus

    1995-01-01

    Styrene is an environmental pollutant, emitted in large quantities to the atmosphere by various industrial sectors. Legislation requires industry to reduce the emission of styrene. One option to purify industrial waste gases is biological treatment in biofilters. ... Zie: Summary

  8. 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.

  9. 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.

  10. Diversity of Nitrate-Reducing and Denitrifying Bacteria in a Marine Aquaculture Biofilter and their Response to Sulfide

    DEFF Research Database (Denmark)

    Krieger, Bärbel; Schwermer, Carsten U.; Rezakhani, Nastaran

    2006-01-01

    with Alphaproteobacteria but also including Beta- and Gammaproteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. The diversity of the isolates was compared to the cultivation-independent diversity of nitrate-reducing and denitrifying bacteria based on narG and nosZ as functional marker genes. Growth experiments...

  11. 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.

  12. 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.

  13. Microbiological and kinetic aspects of a biofilter for the removal of toluene from waste gases

    Science.gov (United States)

    Acuna; Perez; Auria; Revah

    1999-04-20

    Microbiological and kinetic aspects of a biofilter inoculated with a consortium of five bacteria and two yeast adapted to remove toluene vapors were investigated. Initially the toluene sorption isotherm on peat and the effect of different environmental conditions on the toluene consumption rates of this consortium were measured. The fast start-up of the biofilter and the decay in the elimination capacity (EC) were reproduced using microcosm assays with toluene successive additions. Nutrient limitation and a large degree of heterogeneity were also detected. EC values, extrapolated from microcosms, were higher than biofilter EC when it was operating close to 100% efficiency but tended to relate better as the biofilter EC diminished. In studies on the microbial evolution in the biofilter, an increase in the cell count and variation in the ecology of the consortium were noted. Bacterial counts up to 10 x 10(11) cfu/gdry peat were found in 88 days, which corresponds to about a 10(4) increase from inoculum. Observations with SEM showed a nonuniform biofilm development on the support and the presence of an extracellular material. The results obtained in this work demonstrated that activity measurement in microcosms concomitant to the biofilter operation could be an important tool for understanding, predicting and improving the biofiltration performance. Copyright 1999 John Wiley & Sons, Inc.

  14. Role of Thiobacillus thioparus in the biodegradation of carbon disulfide in a biofilter packed with a recycled organic pelletized material.

    Science.gov (United States)

    Prenafeta-Boldú, Francesc X; Rojo, Naiara; Gallastegui, Gorka; Guivernau, Miriam; Viñas, Marc; Elías, Ana

    2014-07-01

    This study reports the biodegradation of carbon disulfide (CS2) in air biofilters packed with a pelletized mixture of composted manure and sawdust. Experiments were carried out in two lab-scale (1.2 L) biofiltration units. Biofilter B was seeded with activated sludge enriched previously on CS2-degrading biomass under batch conditions, while biofilter A was left as a negative inoculation control. This inoculum was characterized by an acidic pH and sulfate accumulation, and contained Achromobacter xylosoxidans as the main putative CS2 biodegrading bacterium. Biofilter operation start-up was unsuccessfully attempted under xerophilic conditions and significant CS2 elimination was only achieved in biofilter A upon the implementation of an intermittent irrigation regime. Sustained removal efficiencies of 90-100 % at an inlet load of up to 12 g CS2 m(-3) h(-1) were reached. The CS2 removal in this biofilter was linked to the presence of the chemolithoautotrophic bacterium Thiobacillus thioparus, known among the relatively small number of species with a reported capacity of growing on CS2 as the sole energy source. DGGE molecular profiles confirmed that this microbe had become dominant in biofilter A while it was not detected in samples from biofilter B. Conventional biofilters packed with inexpensive organic materials are suited for the treatment of low-strength CS2 polluted gases (IL biofiltration of recalcitrant compounds has been highlighted.

  15. Evaluation of the bioremoval of Cr(VI) and TOC in biofilters under continuous operation using response surface methodology.

    Science.gov (United States)

    Leles, Daniela M A; Lemos, Diego A; Filho, Ubirajara C; Romanielo, Lucienne L; de Resende, Miriam M; Cardoso, Vicelma L

    2012-06-01

    In the present study, the bioremoval of Cr(VI) and the removal of total organic carbon (TOC) were achieved with a system composed by an anaerobic filter and a submerged biofilter with intermittent aeration using a mixed culture of microorganisms originating from contaminated sludge. In the aforementioned biofilters, the concentrations of chromium, carbon, and nitrogen were optimized according to response surface methodology. The initial concentration of Cr(VI) was 137.35 mg l(-1), and a bioremoval of 85.23% was attained. The optimal conditions for the removal of TOC were 4 to 8 g l(-1) of sodium acetate, >0.8 g l(-1) of ammonium chloride and 60 to 100 mg l(-1) of Cr(VI). The results revealed that ammonium chloride had the strongest effect on the TOC removal, and 120 mg l(-1) of Cr(VI) could be removed after 156 h of operation. Moreover, 100% of the Cr(VI) and the total chromium content of the aerobic reactor output were removed, and TOC removals of 80 and 87% were attained after operating the anaerobic and aerobic reactors for 130 and 142 h, respectively. The concentrations of cells in both reactors remained nearly constant over time. The residence time distribution was obtained to evaluate the flow through the bioreactors.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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…

  3. 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.

  4. 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.

  5. 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...

  6. 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.

  7. 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...

  8. Performance of a pilot-scale compost biofilter treating gasoline vapor

    International Nuclear Information System (INIS)

    Wright, W.F.; Schroeder, E.D.; Chang, D.P.Y.

    1997-01-01

    A pilot-scale compost biofiltration system was operated as gasoline soil vapor extraction site in Hayward, California for one year. The media was composed of equal volumes of compost and perlite, a bulking agent. Supplements added included nitrogen (as KNO 3 ), a gasoline degrading microbial inoculum, buffer (crushed oyster shell), and water. The biofiltration system was composed of four identical units with outside dimensions of 1.2 x 1.2 x 1.2 m (4 x 4 x 4 ft) operated in an up-flow mode. The units were configured in parallel during the first eight months and then reconfigured to two parallel systems of two units in series. Air flux values ranged from 0.29 to 1.0 m 3 /m 2 per min. Inlet total petroleum hydrogen hydrocarbon (TPH gas ) concentrations ranged from 310 to 2,700 mg/m 3 . The average empty bed contact time was 2.2 min. Following start-up, performance of the individual biofilters varied considerably for a seven-month period. The principal factor affecting performance appeared to be bed moisture content. Overall TPH gas removals reached 90% for short periods in one unit, and BTEX removals were typically above 90%. Drying resulted in channeling and loss of bed activity. Management of bed moisture content improved over the study period, and recovery of system performance was achieved without replacement of bed media. Overall TPH gas removals exceeded 90% during the final 50 days of the study

  9. 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.

  10. 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

  11. Long-term studies in COD elimination and nitrification in an overcongested packed-bed reactor (biofilter); Langzeituntersuchungen zur CSB-Elimination und Nitrifikation in einem ueberstauten Festbettreaktor (Biofilter)

    Energy Technology Data Exchange (ETDEWEB)

    Engelhart, M.; Dichtl, N. [Technische Univ. Braunschweig (Germany). Inst. fuer Siedlungswasserwirtschaft

    1999-07-01

    On a semi-technical scale, two process combinations were tested for their suitability for COD elimination and nitrification in combination with an overcongested packed-bed reactor (biofilter). (orig.) [German] Im halbtechnischen Massstab wurden zwei Verfahrenskombinationen unter Einbeziehung eines ueberstauten Festbettreaktors (Biofilter) auf ihre Tauglichkeit zur CSB-Elimination und Nitrifikation untersucht. (orig.)

  12. An investigation into the removal of Salmonella and enteric indicator bacteria from the separated liquid fraction of raw or anaerobically digested pig manure using novel on-farm woodchip biofilters.

    Science.gov (United States)

    McCarthy, G; Lawlor, P G; Carney, K N; Zhan, X; Gutierrez, M; Gardiner, G E

    2015-05-01

    The objective was to investigate the removal of Salmonella and enteric indicator bacteria from the liquid fraction of raw and anaerobically digested (AD) pig manure in woodchip biofilters over a 14 week (98 day) period. Antibiotic susceptible Salmonella Infantis was detected in one influent material (liquid fraction of raw manure) on two occasions but was not found in the effluent at any time point. Furthermore, mean coliform reductions of 56% were observed in the biofilters treating the liquid fraction of raw manure. However, a mean increase of 228% was found in those treating the liquid from AD manure, despite the fact that the microbial challenge to these biofilters was lower. In addition, relatively high coliform counts were still present in the effluent from both biofilter treatments, especially in the systems treating the liquid fraction of AD manure. However, findings for Escherichia coli and Enterococcus were more promising, with reductions observed for both treatments (10 and 18.5% for E. coli and 71 and 87% for Enterococcus). Moreover, E. coli and Enterococcus were at, or just above, the limit of detection in the final effluents. Overall, although, there are no microbial limits for discharge or washwaters, the woodchip filter effluent would appear safe for discharge to waterways or use on-farm as regards Salmonella, E. coli and Enterococcus but not coliform. In conclusion, woodchip biofilters offer potential as a low-cost sustainable novel treatment option for the removal of pathogens from the liquid fraction of pig manure. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. 40 CFR 122.25 - Aquaculture projects (applicable to State NPDES programs, see § 123.25).

    Science.gov (United States)

    2010-07-01

    ... DISCHARGE ELIMINATION SYSTEM Permit Application and Special NPDES Program Requirements § 122.25 Aquaculture... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Aquaculture projects (applicable to State NPDES programs, see § 123.25). 122.25 Section 122.25 Protection of Environment ENVIRONMENTAL...

  14. 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.

  15. 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.

  16. Investigation of efficiency of air cleaning from acetone using a segmental construction biofilter

    Directory of Open Access Journals (Sweden)

    Denas Bacevičius

    2015-10-01

    Full Text Available Volatile organic compounds, e. g. acetone, have a direct impact on climate change, decrease of ozone in the air, and on the growth of greenhouse effect. One of the most popular air purifying methods from VOC is a biological air cleaning. Experimental investigations were conducted to determine the efficiency of the new structure of biofilter with polypropylene plates segments. During the investigations the efficiency of segmental construction biofilter of air purification at different initial concentrations of pollutants was determined. Different concentrations of pollutants were estimated during the acetone dilution with water. During the tests the efficiency of biofilter air purification from acetone vapor and its change under different concentrations of vapors was set. Based on test results, the maximum efficiency of biofilter air purification was up to 93%. Studies have shown that increasing the allowable pollutant concentration, the efficiency of air purification unit decreases. Increasing the concentration of supplied acetone vapor into the biofilter from 232 to 701 mg/m3, cleaning efficiency decreased from 92.8 to 82.3%. Since microorganisms fail to oxidize organic compounds, the filter works better at lower initial concentrations of pollutants.

  17. Aerated biofilters with multiple-level air injection configurations to enhance biological treatment of methane emissions.

    Science.gov (United States)

    Farrokhzadeh, Hasti; Hettiaratchi, J Patrick A; Jayasinghe, Poornima; Kumar, Sunil

    2017-09-01

    Aiming to improve conventional methane biofilter performance, a multiple-level aeration biofilter design is proposed. Laboratory flow-through column experiments were conducted to evaluate three actively-aerated methane biofilter configurations. Columns were aerated at one, two, and three levels of the bed depth, with air introduced at flow rates calculated from methane oxidation reaction stoichiometry. Inlet methane loading rates were increased in five stages between 6 and 18mL/min. The effects of methane feeding rate, levels of aeration, and residence time on methane oxidation rates were determined. Samples collected after completion of flow-through experiments were used to determine methane oxidation kinetic parameters, V max , K m , and methanotrophic community distribution across biofilter columns. Results obtained from mixed variances analysis and response surfaces, as well as methanotrophic activity data, suggested that, biofilter column with two aeration levels has the most even performance over time, maintaining 85.1% average oxidation efficiency over 95days of experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Biofilm structure and mass transfer in a gas phase trickle-bed biofilter.

    Science.gov (United States)

    Zhu, X; Suidan, M T; Alonso, C; Yu, T; Kim, B J; Kim, B R

    2001-01-01

    Mass transport phenomena occurring in the biofilms of gas phase trickle-bed biofilters are investigated in this study. The effect of biofilm structure on mass transfer mechanisms is examined using experimental observation from the operating of biofilters, microelectrode techniques and microscopic examination. Since the biofilms of biofilters used for waste gas treatment are not completely saturated with water, there is not a distinguishable liquid layer outside the biofilm. Results suggest that due to this characteristic, gas phase substrates (such as oxygen or volatile organic compounds) may not be limited by the aqueous phase because transport of the compound into the biofilm can occur directly through non-wetted areas. On the other hand, for substrates that are present only in the liquid phase, such as nitrate, the mass transfer limitation is more serious because of the limited liquid supply. Microscopic observations show that a layered structure with void spaces exists within the biofilm. Oxygen concentration distributions along the depth of the biofilms are examined using an oxygen microelectrode. Results indicate that there are some high dissolved oxygen zones inside the biofilm, which suggests the existence of passages for oxygen transfer into the deeper sections of the biofilm in a gas phase trickle-bed biofilter. Both the low gas-liquid mass transfer resistance and the resulting internal structure contribute to the high oxygen penetration within the biofilms in gas phase trickle-bed biofilters.

  19. Investigation of Removal Capacities of Biofilters for Airborne Viable Micro-Organisms

    Science.gov (United States)

    Soret, Rémi; Fanlo, Jean-Louis; Malhautier, Luc; Geiger, Philippe; Bayle, Sandrine

    2018-01-01

    New emerging issues appears regarding the possible aerosolization of micro-organisms from biofilters to the ambient air. Traditional bioaerosol sampling and cultural methods used in literature offer relative efficiencies. In this study, a new method revolving around a particle counter capable of detecting total and viable particles in real time was used. This counter (BioTrak 9510-BD) uses laser-induced fluorescence (LIF) technology to determine the biological nature of the particle. The concentration of viable particles was measured on two semi-industrial pilot scale biofilters in order to estimate the Removal Efficiency in viable particles (REvp) in stable conditions and to examine the influence of pollutant feeding and relative humidification of the gaseous effluent on the REvp. The REvp of biofilters reached near 80% and highlighted both the stability of that removal and the statistical equivalence between two identical biofilters. Pollutant deprivation periods of 12 h, 48 h and 30 days were shown to have no influence on the biofilters’ removal capacity, demonstrating the robustness and adaptation capacities of the flora. In contrast, a 90-day famine period turned the biofilters into emitters of viable particles. Finally, the humidification of the effluent was shown to negatively influence the removal capacity for viable particles, as drying off the air was shown to increase the REvp from 60 to 85%. PMID:29562709

  20. Ammonia-nitrogen and Phosphate Reduction by Bio-Filter using Factorial Design

    Science.gov (United States)

    Kasmuri, Norhafezah; Ashikin Mat Damin, Nur; Omar, Megawati

    2018-02-01

    Untreated landfill leachate is known to have endangered the environment. As such new treatment must be sought to ensure its cost-effective and sustainable treatment. Thus this paper reports the effectiveness of bio-filter to remove pollutants. In this research, the reduction of nutrients concentration was evaluated in two conditions: using bio-filter and without bio-filter. Synthetic wastewater was used in the batch culture. It was conducted within 21 days in the initial mediums of 100 mg/L ammonia-nitrogen. The nitrification medium consisted of 100 mg/L of ammonia-nitrogen while the nitrite assay had none. The petri dish experiment was also conducted to observe the existence of any colony. The results showed 22% of ammonia- nitrogen reduction and 33% phosphate in the nitrification medium with the bio-filter. The outcome showed that the bio-filter was capable to reduce the concentration of pollutants by retaining the slow growing bacteria (AOB and NOB) on the plastic carrier surface. The factorial design was applied to study the effect of the initial ammonia-nitrogen concentration and duration on nitrite-nitrogen removal. Finally, a regression equation was produced to predict the rate of nitrite-nitrogen removal without conducting extended experiments and to reduce the number of trials experiment.

  1. Nitrification in moving bed and fixed bed biofilters treating effluent water from a large commercial outdoor rainbow trout RAS

    DEFF Research Database (Denmark)

    Suhr, Karin; Pedersen, Per Bovbjerg

    2010-01-01

    The nitrification performance of two fixed bed (FB) biofilters and two moving bed (MB) biofilters was evaluated. They received the same cold (8 degrees C) influent water from a commercial outdoor RAS facility producing rainbow trout (average density 32 kg m(-3)). The filters were constructed as f...

  2. 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.

  3. 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

  4. Study of performances, stability and microbial characterization of a Sequencing Batch Biofilter Granular Reactor working at low recirculation flow.

    Science.gov (United States)

    De Sanctis, Marco; Beccari, Mario; Di Iaconi, Claudio; Majone, Mauro; Rossetti, Simona; Tandoi, Valter

    2013-02-01

    The Sequencing Batch Biofilter Granular Reactor (SBBGR) is a promising wastewater treatment technology characterized by high biomass concentration in the system, good depuration performance and low sludge production. Its main drawback is the high energy consumption required for wastewater recirculation through the reactor bed to ensure both shear stress and oxygen supply. Therefore, the effect of low recirculation flow on the long-term (38 months) performance of a laboratory scale SBBGR was studied. Both the microbial components of the granules, and their main metabolic activities were evaluated (heterotrophic oxidation, nitrification, denitrification, fermentation, sulphate reduction and methanogenesis). The results indicate that despite reduced recirculation, the SBBGR system maintained many of its advantageous characteristics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Utilization of toxic and vapors as alternate electron acceptors in biofilters

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.D.; Apel, W.A.; Walton, M.R.

    1997-08-01

    Conceptually, biofilters are vapor phase bioreactors that rely on microorganisms in the bed medium to oxidize contaminants in off-gases flowing through the bed to less hazardous compounds. In the most studied and utilized systems reduced compounds such as fuel hydrocarbons are enzymatically oxidized to compounds such as carbon dioxide and water. In these types of reactions the microorganisms in the bed oxidize the contaminant and transfer the electrons to oxygen which is the terminal electron acceptor in the process. In essence the contaminant is the carbon and energy source for the microorganisms in the bed medium and through this catabolic process oxygen is reduced to water. An example of this oxidation process can be seen during the degradation of benzene and similar aromatic compounds. Aromatics are initially attacked by a dioxygenase enzyme which oxidizes the compounds to a labile dihydrodiole which is spontaneously converted to a catechol. The dihydroxylated aromatic rings is then opened by oxidative {open_quotes}ortho{close_quotes} or {open_quotes}meta{close_quotes} cleavage yielding cis, cis-muconic acid or 2-hydroxy-cis, cis-muconic semialdehyde, respectively. These organic compounds are further oxidized to carbon dioxide or are assimilated for cellular material. This paper describes the conversion of carbon tetrachloride using methanol as the primary carbon and energy source.

  6. 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 ...

  7. 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...

  8. 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; ...

  9. Removal of hydrogen sulphide from pig house using biofilter with fungi

    DEFF Research Database (Denmark)

    Hansen, Michael J.; Pedersen, Claus L.; Søgaard Jensen, Louise H.

    2018-01-01

    was to investigate if this high removal could be due to the presence of fungi. The removal of reduced sulphur compounds in a 600-mm wide cellulose biofilter was measured at depths of 0, 200, 400 and 600 mm and the results compared with estimated fungal hyphae surface area per biofilm area. Over 19 months, removal...... of hydrogen sulphide was measured during periods with and without fungi. The results demonstrate a correlation between the fungal hyphae surface area and the removal of hydrogen sulphide with the highest removal in the first 200 mm of the biofilter and decreasing removal with depth. During periods...... area caused by the hyphae....

  10. 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.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    H.M. Joesting

    2016-05-01

    Full Text Available Recent technological advances in marine shrimp and finfish aquaculture alleviate many of the environmental risks associated with traditional aquaculture, but challenges remain in cost-effective waste management. Liquid effluent from freshwater aquaculture systems has been shown to be effective in agricultural crop production (i.e., aquaponics, but few studies have explored the potential for reuse of marine aquaculture effluent, particularly the solid fraction. The purpose of this study was to investigate the use of marine aquaculture solid waste as a nutrient source for the nursery production of two salt tolerant plants commonly used in coastal salt marsh restoration, Spartina alterniflora (smooth cordgrass and Juncus roemerianus (black needlerush. Specifically, measurements of plant biomass and tissue nitrogen and phosphorus allocation were compared between plants fertilized with dried shrimp biofloc solids and unfertilized controls, as well as between plants fertilized with dried fish solids and unfertilized controls. In both experiments, S. alterniflora plants fertilized with marine aquaculture solids showed few significant differences from unfertilized controls, whereas fertilized J. roemerianus plants had significantly greater biomass and absorbed and incorporated more nutrients in plant tissue compared to unfertilized controls. These results suggest that J. roemerianus may be a suitable plant species for the remediation of marine aquaculture solid waste. Keywords: Marine aquaculture, Salt marsh plants, Solid waste, Phytoremediation

  13. 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.

  14. 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

  15. 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. ?

  16. Macrokinetic determination of isopropanol removal using a downward flow biofilter

    Directory of Open Access Journals (Sweden)

    Vissanu Meeyoo

    2004-02-01

    Full Text Available Biofiltration is a process for eliminating contaminants in air using microorganisms immobilized on a surface of solid support media. This technique has been used successfully to control a number of air contaminants such as odors, Volatile Organic Compounds (VOCs, and Hazardous Air Pollutants (HAPs due to its economic attraction.Microorganisms obtained from local activated sludge (Huay-Kwang wastewater treatment plant (Bangkok, Thailand were selectively enriched and inoculated to the biofilter. The downward flow biofilterwas chosen, due to the ease of water compensation at the dry zone, to operate continuously for more than 3 months under various concentrations of isopropanol alcohol (IPA input at a constant filtered air flow rate of 3 L/min. The maximum IPA elimination capacity of 276 g/m3-h was achieved at the IPA inlet of 342 g/m3-h with acetone production rate of 56 g/m3-h as the intermediate. It was also found that the acetone vapour was partly degraded by the acetone-utilizing microorganisms before leaving the bed. In order to understand the transport phenomena of biofiltration, it is necessary to consider the kinetic behavior of the bioreaction. Therefore, this paper introduces Wani’s method of macrokinetic determination based on the simple Monod kinetic (Wani, Lau and Branion, 1999. In this study, the maximum reaction rate per unit volume (Rm and the Monod constant (KM were found to be 0.12 g/m3 -s and 2.72 g/m3 respectively.

  17. PERANAN MANGROVE SEBAGAI BIOFILTER PENCEMARAN AIR WILAYAH TAMBAK BANDENG TAPAK, SEMARANG (Role of Mangrove as Water Pollution Biofilter in Milkfish Pond, Tapak, Semarang

    Directory of Open Access Journals (Sweden)

    Nana T.M. Kariada

    2014-10-01

    Full Text Available ABSTRAK Mangrove yang tumbuh di ujung sungai besar berperan sebagai penampung terakhir bagi limbah dari industri di perkotaan dan perkampungan hulu yang terbawa aliran sungai. Area hutan mangrove mempunyai kemampuan mengakumulasi logam berat yang terdapat dalam ekosistem tempat tumbuhnya. Tujuan yang hendak dicapai dari  penelitian ini adalah mengkaji peranan mangrove sebagai biofilter pencemaran air dan  mengetahui jenis mangrove yang terbaik berperan sebagai biofilter pencemaran air di di lingkungan tambak bandeng Tapak Kota Semarang. Desain yang digunakan dalam penelitian ini adalah deskriptif eksploratif. Berdasarkan hasil penelitian tentang akumulasi logam berat Cu antara air dan sedimen tambak, diperoleh hasil telah terjadi akumulasi Cu dengan Faktor Konsentrasi antara 43-400.  Pada stasiun 3 dan 4 terdapat akumulasi Cu dengan nilai Faktor Konsentrasi 3 dan 0,3. Hal ini menunjukkan akumulasi Cu dari sedimen ke akar mangrove relatif masih kecil. Perbedaan akumulasi dari tiap stasiun penelitian yang diamati menunjukkan adanya perbedaan jenis mangrove yang tumbuh pada masing-masing stasiun penelitian. Mangrove yang berada di lingkungan tambak bandeng wilayah Tapak Kota Semarang disimpulkan dapat berperan sebagai biofilter pencemaran air yang ada di perairan tersebut. Mangrove dari jenis Avicennia marina mempunyai peranan yang lebih baik dari jenis Rhizophora sp sebagai biofilter pencemaran air di lingkungan tambak bandeng Tapak Kota Semarang.   ABSTRACT Mangroves,  that is growing at the end of a great river, has a role as the last place for the waste water from urban and domestic industry at the upstream that were carried by the flow of river. Mangrove area  has  ability to accumulate a heavy metals  which is contained in it. The  goals  from this research is to assess role of mangrove as biofilter of water pollution and to find out the best species of mangrove as biofilter of water pollution in milkifish pond in Tapak, Semarang

  18. 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.

  19. Ethylbenzene removal under mesophilic conditions in a multiple-stage biofilter with macadamia nutshells as carrier material

    OpenAIRE

    Volckaert, Diego; Alvarez Hornos, Francisco Javier; Heynderickx, Philippe; Van Langenhove, Herman

    2011-01-01

    A biofilter was used to treat air polluted with ethylbenzene. Macadamia nutshells, which are a cheap waste product in Thailand, were chosen as the packing material for the biofilter. The moisture content (6.6 w%), water holding capacity (16.8 w%), nutshell density (1.3 g ml-1) and organic content (78.0 w%) of the macadamia nutshell were measured. The biofilter was operated during 5 months, in which several inlet loads (IL), empty bed residence times (EBRT) and temperatures (T) were applied. A...

  20. Treatment of waste gas containing low concentration of dimethyl sulphide (DMS) in a bench-scale biofilter.

    Science.gov (United States)

    Giri, B S; Mudliar, S N; Deshmukh, S C; Banerjee, S; Pandey, R A

    2010-04-01

    Biological treatment of dimethyl sulphide (DMS) was investigated in a bench-scale biofilter, packed with compost along with wood chips, and enriched with DMS degrading microorganism Bacillus sphaericus. The biofilter could remove 62-74% of the inlet DMS, at an optimum loading of 0.484 g/m(3)/h with optimum empty bed contact time (EBCT) of 384 s and an average moisture range of 65-70%. The biodegradative products of DMS were sulphide, thiosulphate and sulphate. Evaluation of microbiological status of the biofilter indicated the presence of other bacterial cultures viz. Paenibacillus polymyxa, and Bacillus megaterium, besides B. sphaericus. Copyright 2009 Elsevier Ltd. All rights reserved.

  1. Biofiltration of Chloroform in a Trickle Bed Air Biofilter Under Acidic Conditions

    Science.gov (United States)

    In this paper, the application of biofiltration is investigated for controlled removal of gas phase chloroform through cometabolic degradation with ethanol. A trickle bed air biofilter (TBAB) operated under acidic pH 4 is subjected to aerobic biodegradation of chloroform and etha...

  2. EVALUATION OF TRICKLE-BED AIR BIOFILTER PERFORMANCE FOR STYRENE REMOVAL

    Science.gov (United States)

    A pilot-scale trickle-bed air biofilter (TBAB) was evaluated for the removal of styrene from a waste gas stream. Six-millimeter (6 mm) Celite pellets (R-635) were used as the biological attachment medium. The operating parameters considered in the study included the styrene vol...

  3. Influence of synthetic packing materials on the gas dispersion and biodegradation kinetics in fungal air biofilters

    NARCIS (Netherlands)

    Prenafeta-Boldú, F.X.; Illa, J.; Groenestijn, J.W. van; Flotats, X.

    2008-01-01

    The biodegradation of toluene was studied in two lab-scale air biofilters operated in parallel, packed respectively with perlite granules (PEG) and polyurethane foam cubes (PUC) and inoculated with the same toluene-degrading fungus. Differences on the material pore size, from micrometres in PEG to

  4. Respirometric oxygen demand determinations of laboratory- and field-scale biofilters

    International Nuclear Information System (INIS)

    Rho, D.; Mercier, P.; Jette, J.F.

    1995-01-01

    A biofiltration experiment operated at three inlet concentrations (425, 830, and 1,450 mg m -3 ), showed that the specific oxygen consumption rate was highly correlated (R = 0.938, n = 23) with the toluene elimination capacity. A radiorespirometric test was found to be more sensitive and appropriate for the field-scale biofilter treating gasoline vapors

  5. Biofilter media gas pressure loss as related to media particle size and particle shape

    DEFF Research Database (Denmark)

    Pugliese, Lorenzo; Poulsen, Tjalfe G.; Røjgaard Andreasen, Rune

    2013-01-01

    Pressure loss (ΔP) is a key parameter for estimating biofilter energy consumption. Accurate predictions of ΔP as a function of air velocity (V) are therefore essential, to assess energy consumption and minimize operation costs. This paper investigates the combined impact of medium particle size...

  6. Hexane abatement and spore emission control in a fungal biofilter-photoreactor hybrid unit

    Energy Technology Data Exchange (ETDEWEB)

    Saucedo-Lucero, J.O. [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain); IPICyT, Instituto Potosino de Investigación Científica y Tecnológica, División de Ciencias Ambientales, Camino a la Presa San José No. 2055, C.P., 78216 San Luis Potosí (Mexico); Quijano, G. [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain); Arriaga, S. [IPICyT, Instituto Potosino de Investigación Científica y Tecnológica, División de Ciencias Ambientales, Camino a la Presa San José No. 2055, C.P., 78216 San Luis Potosí (Mexico); Muñoz, R., E-mail: mutora@iq.uva.es [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid (Spain)

    2014-07-15

    Highlights: • A fungal biofilter/photoreactor was evaluated in terms of hexane and spore removal. • Biofilter supported elimination capacities of ≈35 g m{sup −3} h{sup −1} and CO{sub 2} yields of ≈75%. • The photocatalytic process slightly boosted the hexane abatement performance. • Biofilter emitted fungal spores at concentrations of 2.4 × 10{sup 3}–9.0 × 10{sup 4} CFU m{sup −3}. • Photo-assisted post-treatments resulted in spore deactivation efficiencies of 98%. - Abstract: The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14 min, respectively, and a hexane loading rate of 115 ± 5 g m{sup −3} h{sup −1}. Steady n-hexane elimination capacities of 30–40 g m{sup −3} h{sup −1} were achieved, concomitantly with pollutant mineralization efficiencies of 60–90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48 h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4 × 10{sup 3} to 9.0 × 10{sup 4} CFU m{sup −3}. Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of

  7. Removal of alpha-pinene from gases using biofilters containing fungi

    Science.gov (United States)

    van Groenestijn, J. W.; Liu, J. X.

    Biofiltration is cost-effective for the treatment of gases containing low concentrations of volatile organic compounds (elimination of hydrophobic compounds. Besides that, biofilter operational stability is often hampered by acidification and drying out of the filter bed. To overcome these problems, biofilters with fungi on inert packing material have been developed. Fungi are more resistant to acid and dry conditions than bacteria, and it is hypothesised that the aerial mycelia of fungi, which are in direct contact with the gas, can take up hydrophobic compounds faster than flat aqueous bacterial biofilm surfaces. Alpha-pinene was chosen as a model compound. It is an odorous compound emitted by the wood processing industry. In 2 l biofilter columns four different packing materials were tested: perlite, expanded clay granules, polyurethane foam cubes and compost. The filters were inoculated with forest soil and ventilated with gas containing alpha-pinene. Start up took 1-2 months and removal efficiencies of more than 90% were observed, but mostly ranged from 50% to 90% due to overloading. In the filters containing perlite, clay, polyurethane and compost volumetric removal capacities of, respectively, 24, 33, 38 and 24 g alpha- pinene m -3 filter bed h -1 were attained and the gas pressure drops in the 60 cm high filter beds measured at a superficial gas velocity of 35 m h -1 were 70, 550, 180 and 250 Pa. The results indicate that it is possible to develop biofilters based on the action of fungi with higher elimination capacities for alpha-pinene as reported in literature for bacterial biofilters. The use of polyurethane foam cubes is preferred because of the low gas pressure drop in combination with a high volumetric elimination capacity.

  8. Investigating bacterial populations in styrene-degrading biofilters by 16S rDNA tag pyrosequencing.

    Science.gov (United States)

    Portune, Kevin J; Pérez, M Carmen; Álvarez-Hornos, F Javier; Gabaldón, Carmen

    2015-01-01

    Microbial biofilms are essential components in the elimination of pollutants within biofilters, yet still little is known regarding the complex relationships between microbial community structure and biodegradation function within these engineered ecosystems. To further explore this relationship, 16S rDNA tag pyrosequencing was applied to samples taken at four time points from a styrene-degrading biofilter undergoing variable operating conditions. Changes in microbial structure were observed between different stages of biofilter operation, and the level of styrene concentration was revealed to be a critical factor affecting these changes. Bacterial genera Azoarcus and Pseudomonas were among the dominant classified genera in the biofilter. Canonical correspondence analysis (CCA) and correlation analysis revealed that the genera Brevundimonas, Hydrogenophaga, and Achromobacter may play important roles in styrene degradation under increasing styrene concentrations. No significant correlations (P > 0.05) could be detected between biofilter operational/functional parameters and biodiversity measurements, although biological heterogeneity within biofilms and/or technical variability within pyrosequencing may have considerably affected these results. Percentages of selected bacterial taxonomic groups detected by fluorescence in situ hybridization (FISH) were compared to results from pyrosequencing in order to assess the effectiveness and limitations of each method for identifying each microbial taxon. Comparison of results revealed discrepancies between the two methods in the detected percentages of numerous taxonomic groups. Biases and technical limitations of both FISH and pyrosequencing, such as the binding of FISH probes to non-target microbial groups and lack of classification of sequences for defined taxonomic groups from pyrosequencing, may partially explain some differences between the two methods.

  9. Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

    Energy Technology Data Exchange (ETDEWEB)

    Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

    2004-09-11

    This report summarizes work performed on this project from April 2004 through September 2004. Our previous work demonstrated that a polyurethane foam biofilter could successfully biodegrade the BTEX contaminants found in the SMZ regeneration waste gas stream. However, establishing the biomass on the polyurethane foam packing was relatively time consuming and daily recirculation of a concentrated nutrient solution was required for efficient operation of the foam biofilter. To simplify the start up and operating requirements of the biofilter system, a simple, compost-based biofilter was investigated for its ability to treat the BTEX contaminants generated during the SMZ regeneration process. The investigation of the compost biofilter was divided into three experimental phases that spanned 180 days of biofilter operation. During Phase 1, the biofilter was continuously supplied a BTEX-contaminated waste gas stream. During Phase 2, a series of periodic shutdown tests were conducted to assess how the biofilter responded when the BTEX feed was discontinued for periods ranging from 1 day to 2.8 days. The Phase 3 experiments focused on determining how the biofilter would handle periodic spikes in inlet BTEX concentration as would be expected when it is coupled with an SMZ column. Results from the continuous feed (Phase 1) experiments demonstrated that the compost biofilter could maintain BTEX removals of greater than 98% within two weeks of startup. Results of the shutdown experiments indicated that benzene removal was the most sensitive to interruptions in the BTEX feed. Nevertheless, the BTEX removal efficiency exceeded 95% within 6 hours of reestablishing the BTEX feed to the biofilter. When the biofilter was subjected to periodic spikes in BTEX concentration (Phase 3), it was found that the total BTEX removal efficiency stabilized at approximately 75% despite the fact that the biofilter was only fed BTEX contaminants 8 hours per day. Finally, the effects of nutrient

  10. 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.

  11. 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.

  12. 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....

  13. 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, ...

  14. 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.

  15. 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...

  16. 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...

  17. 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 ...

  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. 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...

  20. 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

  1. Evaluation of dispersion methods for enumeration of microorganisms from peat and activated carbon biofilters treating volatile organic compounds.

    Science.gov (United States)

    Khammar, Nadia; Malhautier, Luc; Degrange, Valérie; Lensi, Robert; Fanlo, Jean-Louis

    2004-01-01

    To enumerate microorganisms having colonized biofilters treating volatile organic compounds, it is necessary firstly to evaluate dispersion methods. Crushing, shaking and sonication were then tested for the removal of microflora from biofilters packing materials (peat and activated carbon). Continuous or discontinuous procedures, and addition of glass beads had no effect on the number of microorganisms removed from peat particles. The duration of treatment also had no effect for shaking and crushing, but the number of microorganisms after 60 min of treatment with ultrasound was significantly higher than that obtained after 0.5 min. The comparison between these methods showed that crushing was the most efficient for the removal of microorganisms from both peat and activated carbon. The comparison between three chemical dispersion agents showed that 1% Na-pyrophosphate was less efficient, compared with 200 mM phosphate buffer or 1% Na-hexametaphosphate. To optimize the cultivation of microorganisms, three different agar media were compared. Tryptic soy agar tenfold diluted (TSA 1/10) was the most suitable medium for the culture of microflora from a peat biofilter. For the activated carbon biofilter, there was no significant difference between Luria Bertoni, TSA 1/10, and plate count agar. The optimized extraction and enumeration protocols were used to perform a quantitative characterization of microbial populations in an operating laboratory activated carbon biofilter and in two parallel peat biofilters.

  2. 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.

  3. 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 ...

  4. 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

  5. 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,…

  6. 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 ...

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. Biofiltration of methanol in an organic biofilter using peanut shells as medium.

    Science.gov (United States)

    Ramirez-Lopez, E M; Corona-Hernandez, J; Avelar-Gonzalez, F J; Omil, F; Thalasso, F

    2010-01-01

    Biofiltration consists of a filter-bed of organic matter serving both as carrier for the active biomass and as nutrient supply, through which the polluted gas passes. The selection of a suitable medium material is of major importance to ensure optimum biofilter efficiency. Peanut shells are an agricultural byproduct locally available in large quantities at a low price in most tropical and sub-tropical countries. A previous study showed that peanut shells are physically and chemically suitable for biofiltration. This paper presents the results obtained during a six month biofiltration experiment using peanut shells as medium and methanol as air pollutant. It is shown that peanut shells are potentially suitable as biofiltration medium, since degradation rates of up to 30 kg MeOH/m(3)d with an empty bed residence time of 19s was obtained. The biofilter showed a good resistance to shock load and no operational problems were observed.

  15. PENGOLAHAN AIR LINDI DENGAN PROSES KOMBINASI BIOFILTER ANAEROB-AEROB DAN WETLAND

    Directory of Open Access Journals (Sweden)

    Mochtar Hadiwidodo

    2012-09-01

    Full Text Available In Indonesia leachate is still an issue yet to be addressed. With a high content of pollutant parameters and lack of government support resulting landfill must think about the appropriate treatment to be safe for treating waste when discarded into the environment. Biofilter methods and wetland is the one of alternatives leachate treatment that can be used. This method does not require a large operating costs and does not require skilled professionals to operate it. With a combination of wetland and biofilter, it is expected to reduce the content of pollutants in the leachate, so it can be meet the wastewater quality standards which set by the government. The levels of pollutants were tested in this study is the BOD5, COD, TSS, ammonia, nitrite and nitrate

  16. Exploring the potential of fungi for methane abatement: Performance evaluation of a fungal-bacterial biofilter.

    Science.gov (United States)

    Lebrero, Raquel; López, Juan Carlos; Lehtinen, Iiro; Pérez, Rebeca; Quijano, Guillermo; Muñoz, Raúl

    2016-02-01

    Despite several fungal strains have been retrieved from methane-containing environments, the actual capacity and role of fungi on methane abatement is still unclear. The batch biodegradation tests here performed demonstrated the capacity of Graphium sp. to co-metabolically biodegrade methane and methanol. Moreover, the performance and microbiology of a fungal-bacterial compost biofilter treating methane at concentrations of ∼2% was evaluated at empty bed residence times of 40 and 20 min under different irrigation rates. The daily addition of 200 mL of mineral medium resulted in elimination capacities of 36.6 ± 0.7 g m(-3) h(-1) and removal efficiencies of ≈90% at the lowest residence time. The indigenous fungal community of the compost was predominant in the final microbial population and outcompeted the inoculated Graphium sp. during biofilter operation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. 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

  18. Treatment of micropollutants in municipal wastewater: study of a sequential batch biofilter

    OpenAIRE

    Contijoch Culleré, Andreu

    2014-01-01

    All the experimental part of this final project was done at Laboratoire de Biotechnologie Environnementale (LBE) from the École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, during 6 months (November 2013- May 2014). A fungal biofilter composed of woodchips was designed in order to remove micropollutants from the effluents of waste water treatment plants. Two fungi were tested: Pleurotus ostreatus and Trametes versicolor in order to evaluate their efficiency for the r...

  19. Dynamic olfactometry and GC–TOFMS to monitor the efficiency of an industrial biofilter

    Energy Technology Data Exchange (ETDEWEB)

    Gutiérrez, M.C.; Martín, M.A. [University of Cordoba, Department of Inorganic Chemical and Chemical Engineering, Campus Universitario de Rabanales, Carretera N-IV, km 396, Edificio Marie Curie, 14071 Córdoba (Spain); Pagans, E.; Vera, L. [Odournet SL, Parc de Recerca UAB, Edificio Eureka, Espacio P2M2, 08193, Bellaterra, Cerdanyola del Vallès, Barcelona (Spain); García-Olmo, J. [NIR/MIR Spectroscopy Unit, Central Service for Research Support (SCAI), University of Cordoba, Campus de Rabanales, 14071 Cordoba (Spain); Chica, A.F., E-mail: afchica@uco.es [University of Cordoba, Department of Inorganic Chemical and Chemical Engineering, Campus Universitario de Rabanales, Carretera N-IV, km 396, Edificio Marie Curie, 14071 Córdoba (Spain)

    2015-04-15

    Biofiltration is the most widely used technique for eliminating odours in waste treatment plants. Volatile organic compounds (VOCs) are among the odorous compounds emitted by waste management plants, and serve as variables to measure odour emissions depending on the type of aeration process used. In this work, we assess the performance of an industrial-scale biofilter where composting is the main source of VOCs and odour emissions. Dynamic olfactometry is the sensorial technique used to determine odour concentration, while gas chromatography–time of flight-mass spectrometry (GC–TOFMS) is used to perform the chemical characterization. This work examines a total of 82 compounds belonging to 15 odorous families of VOCs, particularly mercaptans, sulphur-containing compounds, alcohols and terpenes, among others. Principal component analysis (PCA) is used to assess the influence of each of these families of VOCs on the total variance of the measure with regard to both the input and output flow of the biofilter. Finally, partial least-squares (PLS) regression is used to estimate the odour concentration in each of the samples taken at the inlet and outlet of the biofilter in each of the samples based on the chemical information provided by chromatographic analysis. The study shows that there is an adequate correlation (r = 0.9751) between real and estimated odour concentrations, both of which are expressed in European odour units per cubic metre (ou{sub E}·m{sup −3}). - Highlights: • Odour and VOC removal by industrial biofilter was evaluated. • Dynamic olfactometry and GC-TOF MS were the techniques used. • The compost aeration mode was considered in this study. • The influence of 15 VOC families on sample variance was demonstrated by PCA. • Odour concentration was predicted from selected chromatographic information by PLS.

  20. Efficiency of bioaugmentation in the removal of organic matter in aquaculture systems Eficiência da bioadição na remoção de matéria orgânica em sistemas aquaculturais

    Directory of Open Access Journals (Sweden)

    RB Lopes

    2011-05-01

    Full Text Available Several techniques are currently used to treat effluents. Bioaugmentation is a new bioremediation strategy and has been employed to improve effluent quality by treating the water during the production process. This technology consists basically of the addition of microorganisms able to degrade or remove polluting compounds, especially organic matter and nutrients. The objective of this study was to assess the effects of bioaugmentation on some parameters of organic matter and on the performance of juvenile tilapias in an intensive aquaculture production system. The combination of two bacterial consortiums in a complete randomized design was employed in a factorial analysis with two factors. Statistical differences between treatments were analyzed by the analysis of variance (ANOVA and Tukey test at the 5% level. One of the treatments, heterotrophic bacterial supplementation, was able to reduce biochemical oxygen demand (BOD by 23%, dissolved organic carbon (DOC by 83.7% and phytoplanktonic biomass by 43%. On the other hand, no damage was done to either the physical-chemical indicators of water quality or to the growth performance of juvenile tilapias assessed in this study.Existem diversas tecnologias para tratamento de efluentes, o processo de bioadição consiste em uma vertente da biorremediação e tem sido empregado na melhoria da qualidade dos efluentes através do tratamento da água de produção. Esta tecnologia consiste basicamente na adição de microrganismos com a capacidade de degradar ou remover compostos poluentes, especialmente matéria orgânica e nutrientes. Este estudo objetivou avaliar os efeitos da suplementação de composto bioativo sobre alguns parâmetros de matéria orgânica e de desempenho de juvenis de tilápias em um sistema intensivo de produção aquacultural. Foi empregada a combinação de dois consórcios bacterianos em delineamento inteiramente aleatorizado, em um esquema fatorial com dois fatores. As diferen

  1. Predictive Power of Clean Bed Filtration Theory for Fecal Indicator Bacteria Removal in Stormwater Biofilters

    Science.gov (United States)

    Parker, E.; Rippy, M.; Mehring, A.; Winfrey, B.; Ambrose, R. F.; Levin, L. A.; Grant, S. B.

    2017-12-01

    Green infrastructure (also referred to as low impact development, or LID) has the potential to transform urban stormwater runoff from an environmental threat to a valuable water resource. Here we focus on the removal of fecal indicator bacteria (FIB, a pollutant responsible for runoff associated inland and coastal beach closures) in stormwater biofilters (a common type of green infrastructure). Drawing on a combination of previously published and new laboratory studies of FIB removal in biofilters, we find that 66% of the variance in FIB removal rates can be explained by clean bed filtration theory (CBFT, 31%), antecedent dry period (14%), study effect (8%), biofilter age (7%), and the presence or absence of shrubs (6%). Our analysis suggests that, with the exception of shrubs, plants affect FIB removal indirectly by changing the infiltration rate, not directly by changing the FIB removal mechanisms or altering filtration rates in ways not already accounted for by CBFT. The analysis presented here represents a significant step forward in our understanding of how physicochemical theories (such as CBFT) can be melded with hydrology, engineering design, and ecology to improve the water quality benefits of green infrastructure.

  2. Petroleum environmental research forum field study on biofilters for control of volatile hydrocarbons

    International Nuclear Information System (INIS)

    Leson, G.; Smith, B.J.

    1997-01-01

    A field study on the treatment of volatile petroleum hydrocarbons (PHC) by biofiltration was conducted by the Petroleum Environmental Research Forum (PERF) between 1992 and 1994. Its objective was to assess the technical, regulatory, and economic feasibility of biofiltration for off-gases from petroleum processing and soil remediation equipment. It involved three small-scale biofilters provided by US vendors, treating off-gas from two soil vapor extraction sites and a source of refinery wastewater. Comprehensive monitoring of biofilter operating parameters and performance was conducted. Typically more than 95% of aromatic compounds such as benzene, and odorous reduced sulfur compounds can be removed at residence times of one minute or less, while removal of more than 70% of light aliphatics will require residence times of several minutes, and will thus require correspondingly large filter volumes and higher capital expenditure. The high percentage removal of aromatic hazardous air pollutants (HAP) and odors can generally be accomplished at comparatively short residence times while the need for high-percentage removal, particular of light aliphatics ( 5 ) will generally render biofiltration noncompetitive. Finally, a preliminary economic comparison of biofilters and established control technologies suggested that biofiltration may, for a representative design case involving off-gas from a refinery wastewater treatment operation, offer considerable savings in total cost of air pollution control for petroleum hydrocarbon streams if regulations require the control of aromatic HAP or odors

  3. Use of biofilters and suspended-growth reactors to treat VOC's

    Energy Technology Data Exchange (ETDEWEB)

    Neal, A.B.; Loehr, R.C.

    2000-07-01

    The greater limits placed on volatile organic compound (VOC) emissions by the Clean Air Act Amendments have stimulated evaluation of various VOC treatment methods. Two applicable gas phase treatment technologies are biofiltration and suspended growth reactors. Biofiltration removes contaminants from gas streams that are passed through a bed of biologically active solids. An aerobic suspended-growth reactor (SGR) removes VOCs by biologically treating contaminated air bubbled through an aqueous suspension of active microorganisms. This research compared the performance of a typical compost biofilter to a SGR for the removal of a common VOC (toluene) from gas streams. The objective was to evaluate the impact of mass loading on process performance. Major performance parameters investigated were (1) mass emitted and elimination capacity, (2) off-gas concentrations exiting each type of reactor for various mass loadings, and (3) removal efficiencies obtained by each type of reactor. The results indicated that SGRs can effectively treat gases containing VOCs. For mass loadings ranging from 5 to 30 mg/l-h, the biofilters and SGRs achieved similar VOC removals, in the range of 96--99.7%. Drying of the biofilter medium occurred a high mass loadings. In the SGRs, at mass loadings greater than 17 mg/l-h, process performance decreased when an unknown colored substance was present.

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

    Science.gov (United States)

    Gudding, Roar; Van Muiswinkel, Willem B

    2013-12-01

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

  5. 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.

  6. 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

  7. New aquaculture drugs under FDA review

    Science.gov (United States)

    Bowker, James D.; Gaikowski, Mark P.

    2012-01-01

    Only eight active pharmaceutical ingredients available in 18 drug products have been approved by the U.S. Food and Drug Administration for use in aquaculture. The approval process can be lengthy and expensive, but several new drugs and label claims are under review. Progress has been made on approvals for Halamid (chloramine-T), Aquaflor (florfenicol) and 35% PeroxAid (hydrogen peroxide) as therapeutic drugs. Data are also being generated for AQUI-S 20E, a fish sedative.

  8. 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...

  9. Merging remotely sensed data, models and indicators for a sustainable development of coastal aquaculture in Algeria

    Science.gov (United States)

    Brigolin, Daniele; Venier, Chiara; Amine Taji, Mohamed; Lourguioui, Hichem; Mangin, Antoine; Pastres, Roberto

    2014-05-01

    Finfish cage farming is an economically relevant activity, which exerts pressures on coastal systems and thus require a science-based management, based on the Ecosystem Approach, in order to be carry out in a sustainable way. Within MEDINA project (EU 282977), ocean color data and models were used for estimating indicators of pressures of aquaculture installations along the north African coast. These indicators can provide important support for decision makers in the allocation of new zones for aquaculture, by taking into account the suitability of an area for this activity and minimizing negative environmental effects, thus enhancing the social acceptability of aquaculture. The increase in the number of farms represents a strategic objective for the Algerian food production sector, which is currently being supported by different national initiatives. The case-study presented in this work was carried out in the Gulf of Bejaia. Water quality for aquaculture was first screened based on ocean color CDOM data (http://www.globcolour.info/). The SWAN model was subsequently used to propagate offshore wave data and to derive wave height statistics. On this basis, sub-areas of the Gulf were ranked, according their optimality in respect to cage resistance and fish welfare requirements. At the three best sites an integrated aquaculture impact assessment model was therefore applied: this tool allows one to obtain a detailed representation of fish growth and population dynamics inside the rearing cages, and to simulate the deposition of uneaten food and faeces on the sediment and the subsequent mineralization of organic matter. This integrated model was used to produce a set of indicators of the fish cages environmental interaction under different scenarios of forcings (water temperature, feeding, currents). These model-derived indicators could usefully contribute to the implementation of the ecosystem approach for the management of aquaculture activities, also required by the

  10. Kinetics of the removal of mono-chlorobenzene vapour from waste gases using a trickle bed air biofilter.

    Science.gov (United States)

    Mathur, Anil K; Sundaramurthy, J; Balomajumder, C

    2006-10-11

    The performance of a trickle bed air biofilter (TBAB) in the removal of mono-chlorobenzene (MCB) was evaluated in concentrations varying from 0.133 to 7.187 g m(-3) and at empty bed residence time (EBRT) varying from 37.7 to 188.52 s. More than 90% removal efficiency in the trickle bed air biofilter was achieved for the inlet MCB concentration up to 1.069 g m(-3) and EBRT less than 94.26 s. The trickle bed air biofilter was constructed with coal packing material, inoculated with a mixed consortium of activated sludge obtained from sewage treatment plant. The continuous performance of the removal of MCB in the trickle bed air biofilter was monitored for various gas concentrations, gas flow rates, and empty bed residence time. The experiment was conducted for a period of 75 days. The trickle bed air biofilter degrading MCB with an average elimination capacity of 80 g m(-3) h(-1) was obtained. The effect of starvation was also studied. After starvation period of 8 days, the degradation was low but recovered within a short period of time. Using macrokinetic determination method, the Michaelis-Menten kinetic constant K(m) and maximum reaction rate, r(max) evaluated as 0.121 g m(-3) s(-1) and 7.45 g m(-3), respectively.

  11. 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.

  12. 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.

  13. 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

  14. Minimizing noise in fiberglass aquaculture tanks: Noise reduction potential of various retrofits

    Science.gov (United States)

    Equipment used in intensive aquaculture systems, such as pumps and blowers can produce underwater sound levels and frequencies within the range of fish hearing. The impacts of underwater noise on fish are not well known, but limited research suggests that subjecting fish to noise could result in imp...

  15. A history of fish vaccination. Science-based disease prevention in aquaculture

    NARCIS (Netherlands)

    Gudding, R.; Muiswinkel, van W.B.

    2013-01-01

    Disease prevention and control are crucial in order to maintain a sustainable aquaculture, both economically and environmentally. Prophylactic measures based on stimulation of the immune system of the fish have been an effective measure for achieving this goal. Immunoprophylaxis has become an

  16. The effects of aquaculture noise on hearing, growth and disease resistance of rainbow trout Oncorhynchus mykiss

    Science.gov (United States)

    Intensive aquaculture production often utilizes equipment (e.g., aerators, air and water pumps, harvesters, blowers, filtration systems, and maintenance machinery) that increases noise levels in fish culture tanks. Consequently, chronic exposure to elevated noise levels in tanks could negatively imp...

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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.

  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. Autotrophic nitrogen removal process in a potable water treatment biofilter that simultaneously removes Mn and NH4(+)-N.

    Science.gov (United States)

    Cai, Yan'an; Li, Dong; Liang, Yuhai; Zeng, Huiping; Zhang, Jie

    2014-11-01

    Ammonia (NH4(+)-N) removal pathways were investigated in a potable water treatment biofilter that simultaneously removes manganese (Mn) and NH4(+)-N. The results indicated a significant loss of nitrogen in the biofilter. Both the completely autotrophic nitrogen removal over nitrite (CANON) process and nitrification were more likely to contribute to NH4(+)-N removal. Moreover, the model calculation results demonstrated that the CANON process contributed significantly to the removal of NH4(+)-N. For influent NH4(+)-N levels of 1.030 and 1.749mg/L, the CANON process contribution was about 48.5% and 46.6%, respectively. The most important finding was that anaerobic ammonia oxidation (ANAMMOX) bacteria were detectable in the biofilter. It is interesting that the CANON process was effective even for such low NH4(+)-N concentrations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Evaluation of trickle-bed air biofilter performance under periodic stressed operating conditions as a function of styrene loading.

    Science.gov (United States)

    Kim, Daekeun; Cai, Zhangli; Sorial, George A

    2005-02-01

    Trickle-bed air biofilters (TBABs) are suitable for treating volatile organic compounds (VOCs) at a significantly high practical loading because of their controlled environmental conditions. The application of TBAB for treating styrene-contaminated air under periodic backwashing and cyclical nonuse periods at a styrene loading of 0.64-3.17 kg chemical oxygen demand (COD)/m3 x day was the main focus of this study. Consistent long-term efficient performance of TBAB strongly depended on biomass control. A periodic in situ upflow with nutrient solution under media fluidization, that is, backwashing, was approached in this study. Two different nonuse periods were employed to simulate a shutdown for equipment repair or during weekends and holidays. The first is a starvation period without styrene loading, and the second is a stagnant period, which reflects no flow passing through the biofilter. For styrene loadings up to 1.9 kg COD/m3 x day, removal efficiencies consistently above 99% were achieved by conducting a coordinated biomass control strategy, that is, backwashing for 1 hr once per week. Under cyclical nonuse periods for styrene loadings up to 1.27 kg COD/m3 x day, stable long-term performance of the biofilter was maintained at more than 99% removal without employing backwashing. No substantial impact of nonuse periods on the biofilter performance was revealed. However, a coordinated biomass control by backwashing subsequently was unavoidable for attaining consistently high removal efficiency at a styrene loading of 3.17 kg COD/m3 x day. As styrene loading was increased, reacclimation of the biofilter to reach the 99% removal efficiency following backwashing or the nonuse periods was delayed. After the non-use periods, the response of the biofilter was a strong function of the biomass in the bed. No significant difference between the effects of the two different nonuse periods on TBAB performance was observed during the study period.

  5. 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...

  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. A Comparative Study of Physical and Chemical Processes for Removal of Biomass in Biofilters

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Mendoza-Pérez

    2011-08-01

    Full Text Available After 6 months of operation a long-term biofilter was stopped for two weeks and then it was started up again for a second experimental period of almost 1.3 years, with high toluene loads and submitted to several physical and chemical treatments in order to remove excess biomass that could affect the reactor’s performance due to clogging, whose main effect is a high pressure drop. Elimination capacity and removal efficiency were determined after each treatment. The methods applied were: filling with water and draining, backwashing, and air sparging. Different flows and temperatures (20, 30, 45 and 60 °C were applied, either with distilled water or with different chemicals in aqueous solutions. Treatments with chemicals caused a decrease of the biofilter performance, requiring periods of 1 to 2 weeks to recover previous values. The results indicate that air sparging with pure distilled water as well as with solutions of NaOH (0.01% w/v and NaOCl (0.01% w/v were the treatments that removed more biomass, working either at 20, 30 or 45 °C and at relatively low flow rates (below 320 L h−1, but with a high biodegradation inhibition after the treatments. Dry biomass (g VS content was determined at three different heights of the biofilter in order to carry out each experiment under the same conditions. The same amount of dry biomass when applying a treatment was established so it could be considered that the biofilm conditions were identical. Wet biomass was used as a control of the biofilter’s water content during treatments. Several batch assays were performed to support and quantify the observed inhibitory effects of the different chemicals and temperatures applied.

  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. 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 ...

  10. 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…

  11. 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 ...

  12. 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...

  13. 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 ...

  14. 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....

  15. 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

  16. 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.

  17. 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 ...

  18. Pathogenic bacteria distribution and extermination in the recirculating aquaculture system of flatfish%鲆鲽类循环水养殖系统中病原菌的分布及杀除工艺

    Institute of Scientific and Technical Information of China (English)

    王印庚; 陈君; 潘传燕; 翟介明; 孙礼娟; 刘江春

    2013-01-01

    The water purification process includes filtration of arc screen,strong aeration,biological filtration and UV sterilization in the recirculating aquaculture system (RAS).The pathogens of skin ulceration,Vibrio splendidus and Vibrio harveyi were selected to be the indicator bacteria for study on bacterial distribution and extermination in RAS of flatfish Cynoglossus semilaevis.Pathogens were found in the feed residues,organic sediment on the tank wall and each instrumental compartment of RAS.Unhealthy fish seedlings and tools used in the cultivation could also bring pathogens into the culture system.Extermination trials illustrated that the filtration of arc screen,strong aeration and UV sterilization were important in the elimination of bacteria.The disinfection rate of pathogens in the organic sediment on tank wall was higher than 90% by washing with KMnO4 at a concentration of 25 × 10-6 mol/L for 1.5min.While the disinfection rate of pathogens on the body surface of the flatfish reached 94.49 % by being soaked in H2O2 at a concentration of 100×10-6mol/L for 10min.This is the first report on the distribution and extermination of pathogenic bacteria in RAS of flatfish,which will provide theoretical data and reference for the management of RAS.%以半滑舌鳎皮肤溃疡病的致病菌灿烂孤菌Vibrio splendidus和哈维氏弧茵Vibrio harveyi为指示茵,研究了循环水养殖系统各环节中细菌分布和消除工艺.结果表明,不健康的苗种携带病原茵进入养殖系统后,可分布在残饵、池壁污物、养殖工具及循环水各处理环节.而弧形筛过滤、曝气池气升、紫外线消毒是循环水养殖系统消除细菌的三大环节.用5×10-6 mol/L的KMnO4溶液浸泡工具2h,对细菌的杀灭率达到100%;用25×10-6 mol/L的KMnO4溶液擦拭养殖池壁污物1.5min后,细菌杀灭率高于90%;用100×10-6 mol/L浓度的H2O2溶液对养殖舌鳎病鱼进行药浴消毒处理10min,对体

  19. Analysis of economic and energy utilization aspects for waste heat aquaculture

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, M.; Wilson, J. V.

    1978-01-01

    A waste heat aquaculture system using extensive culture techniques to produce fin and shellfish is currently under investigation at the Oak Ridge National Laboratory. The system uses nutrients in waste water streams to grow algae and zooplankton which are fed to fish and clams. A tilapia polyculture association and the freshwater clam Corbicula are the animals cultured in the system. The investigations were performed to determine the economic feasibility of the system and examine energy utilization in the system. A net energy analysis was performed to identify the energy saving potential for the system. This analysis includes all energy costs (both direct and indirect) associated with building and operating the system. The results of the economic study indicated that fish production costs of $0.55/kg ($0.25/lb) were possible. This cost, however, depends upon the fish production rate and food conversion efficiency and could rise to as much as $1.65/kg ($0.75/lb). Clam production costs were found to be in the neighborhood of $0.37/kg of clam meat ($1.24/bushel). The energy utilization study results indicated that, when all energy costs are included, fish from the aquaculture system may require only 35% of the net energy now required for fish products from the ocean. However, the energy requirements also depend on system parameters and could be as large as the energy required for ocean caught products. Clams can be produced in the aquaculture system using only about 25% of the net energy required by traditional means. The results of the analysis indicate that the system appears to be economically feasible. They also indicate that significant energy savings are possible if waste heat aquaculture products replace ocean caught products.

  20. 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.

  1. 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.

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

    Science.gov (United States)

    Deniz, H.

    2003-04-01

    potential of aquaculture was fully realised and there were, therefore, no areas specifically designated for aquaculture. Aquaculture development is therefore being restricted by the loss of access to some of the best sites. The most common conflicts occur with environmental protection, tourism, recreation, urbanisation, archaeology and navigation. In order to prevent such conflicts and minimise the environmental impacts the open sea fishery, offshore mariculture systems, and echo-friendly technologies have to be adopted. In addition to that integrated coastal management models must be developed and implemented. Key words: fisheries and aquaculture resources, environment, interaction, tourism, protected areas, mangement and sustainability.

  3. 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.

  4. Treating domestic effluent wastewater treatment by aerobic biofilter with bioballs medium

    Science.gov (United States)

    Permatasari, R.; Rinanti, A.; Ratnaningsih, R.

    2018-01-01

    This laboratory scale research aimed to treat wastewater effluent with advanced treatment utilizing aerobic biofilter with bio-balls medium to obtain effluent quality in accordance with DKI Jakarta Governor Regulation No. 122 of 2005. The seeding and acclimatization were conducted in 4 weeks. The effluent were accommodated in a 150 L water barrel supported by a submersible pump. The effluent were treated in two boxes shaped reactors made of glasses with 36 L of each capacity. These reactors were equipped with aquarium aerators, sampling tap is 10 cm from the base of reactors, and bio-balls with 3 cm diameter are made of PVC. Reactors operated continuously with variations of retention time of 4 hours, 8 hours, 12 hours, 18 hours, and 24 hours and also variations of Carbon: Nitrogen: Phosphor = C: N: P ratio were, 100:5:1, 100:8:1, 100:10:1, 100:12:1, 100:15:1. The results showed that the optimum variance of retention time was 24 hours and the ratio of C:N:P was 100:10:1 yielded the largest removal efficiency for 83,33% of COD, 87,33% of BOD, 82,5% of Ammonia, 79,1% of Nitrate, 92% of Nitrite, 84,82% of Oil and Grease. The concentration parameter resulted from outlet biofilter has met the domestic wastewater quality standard of DKI Jakarta.

  5. Pollution Removal Performance of Laboratory Simulations of Sydney’s Street Stormwater Biofilters

    Directory of Open Access Journals (Sweden)

    James Macnamara

    2017-11-01

    Full Text Available The City of Sydney is constructing more than 21,000 square metres of street biofilter units (raingardens in terms of their Decentralised Water Master Plan (DWMP, for improving the quality of stormwater runoff to Port Jackson, the Cooks River, and the historical Botany Bay. Recharge of the Botany Sand Beds aquifer, currently undergoing remediation by extraction of industrial chlorinated hydrocarbon pollutants, is also envisaged. To anticipate the pollution removal efficiency of field biofilter designs, laboratory soil-column simulations were developed by Western Sydney University partnered with the City. Synthetic stormwater containing stoichiometric amounts of high-solubility pollutant salts in deionised water was passed through 104 mm columns that were layered to simulate monophasic and biphasic field designs. Both designs met the City’s improvement targets for total nitrogen (TN and total phosphorus (TP, with >65% median removal efficiency. Prolonged release of total suspended solids (SS on startup emphasised the need for specifications and testing of proprietary fills. Median removal efficiency for selected heavy metal ecotoxicants was >75%. The researchers suggested that Zinc be added to the targets as proxy for metals, polycyclic aromatic hydrocarbons (PAH and oils/greases co-generated during road use. Simulation results suggested that field units will play an important role in meeting regional stormwater improvement targets.

  6. Evaluating the impact of water supply strategies on p-xylene biodegradation performance in an organic media-based biofilter.

    Science.gov (United States)

    Gallastegui, G; Muñoz, R; Barona, A; Ibarra-Berastegi, G; Rojo, N; Elías, A

    2011-01-30

    The influence of water irrigation on both the long-term and short-term performance of p-xylene biodegradation under several organic loading scenarios was investigated using an organic packing material composed of pelletised sawdust and pig manure. Process operation in a modular biofilter, using no external water supply other than the moisture from the saturated inlet air stream, showed poor p-xylene abatement efficiencies (≈33 ± 7%), while sustained irrigation every 25 days rendered a high removal efficiency (RE) for a critical loading rate of 120 g m(-3)h(-1). Periodic profiles of removal efficiency, temperature and moisture content were recorded throughout the biofilter column subsequent to each biofilter irrigation. Hence, higher p-xylene biodegradation rates were always initially recorded in the upper module, which resulted in a subsequent increase in temperature and a decrease in moisture content. This decrease in the moisture content in the upper module resulted in a higher removal rate in the middle module, while the moisture level in the lower module steadily increased as a result of water condensation. Based on these results, mass balance calculations performed using measured bed temperatures and relatively humidity values were successfully used to account for water balances in the biofilter over time. Finally, the absence of bed compaction after 550 days of continuous operation confirmed the suitability of this organic material for biofiltration processes. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. Maintenance of Fish Health in Aquaculture: Review of Epidemiological Approaches for Prevention and Control of Infectious Disease of Fish.

    Science.gov (United States)

    Assefa, Ayalew; Abunna, Fufa

    2018-01-01

    Aquaculture is rapidly growing part of agriculture worldwide. It makes up around 44 percent of total fish production globally. This increased growth of production is achieved despite facing many challenges in the aquaculture environment. Among production limiting challenges, the infectious disease takes the lion share by causing multibillion-dollar loss annually. To reduce the impact of the fish disease, it is necessary to address health constraints based on scientifically proven and recommended ways. This review aims at pointing out some of the best approaches to prevention and control of infectious disease in aquaculture. Among the effective prevention and control strategies, vaccination is one of the key practices. Types of vaccines for use in fish include killed vaccines, attenuated vaccines, DNA vaccines, recombinant technology vaccines, and synthetic peptide vaccines. Administration techniques of vaccines in fish include oral, injection, or immersion methods. Antibiotics are also in use in aquaculture despite their side effects in the development of drug resistance by microorganisms. Biological and chemical disease control strategies such as using probiotics, prebiotics, and medicinal plants are widely in use. Biosecurity measures in aquaculture can keep the safety of a facility from certain disease-causing agents that are absent in particular system. Farm-level biosecurity measures include strict quarantine measures, egg disinfection, traffic control, water treatments, clean feed, and disposal of mortalities. In conclusion, rather than trying to treat every disease case, it advisable to follow a preventive approach before the event of any disease outbreaks.

  13. Maintenance of Fish Health in Aquaculture: Review of Epidemiological Approaches for Prevention and Control of Infectious Disease of Fish

    Directory of Open Access Journals (Sweden)

    Ayalew Assefa

    2018-01-01

    Full Text Available Aquaculture is rapidly growing part of agriculture worldwide. It makes up around 44 percent of total fish production globally. This increased growth of production is achieved despite facing many challenges in the aquaculture environment. Among production limiting challenges, the infectious disease takes the lion share by causing multibillion-dollar loss annually. To reduce the impact of the fish disease, it is necessary to address health constraints based on scientifically proven and recommended ways. This review aims at pointing out some of the best approaches to prevention and control of infectious disease in aquaculture. Among the effective prevention and control strategies, vaccination is one of the key practices. Types of vaccines for use in fish include killed vaccines, attenuated vaccines, DNA vaccines, recombinant technology vaccines, and synthetic peptide vaccines. Administration techniques of vaccines in fish include oral, injection, or immersion methods. Antibiotics are also in use in aquaculture despite their side effects in the development of drug resistance by microorganisms. Biological and chemical disease control strategies such as using probiotics, prebiotics, and medicinal plants are widely in use. Biosecurity measures in aquaculture can keep the safety of a facility from certain disease-causing agents that are absent in particular system. Farm-level biosecurity measures include strict quarantine measures, egg disinfection, traffic control, water treatments, clean feed, and disposal of mortalities. In conclusion, rather than trying to treat every disease case, it advisable to follow a preventive approach before the event of any disease outbreaks.

  14. 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...

  15. 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...

  16. 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.

  17. 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.

  18. Water withdrawal for brackish and inland aquaculture, and options to produce more fish in ponds with present water use

    NARCIS (Netherlands)

    Verdegem, M.C.J.; Bosma, R.H.

    2009-01-01

    This paper reviews freshwater use in inland and coastal pond aquaculture, and focuses on options to increase productivity while reducing water use. Total freshwater use depends on system-associated and feed-associated water losses. System-associated water losses depend on total area, evaporation,

  19. PERBANDINGAN DESAIN IPAL ANAEROBIC BIOFILTER DENGAN ROTATING BIOLOGICAL CONTACTOR UNTUK LIMBAH CAIR TEKSTIL DI SURABAYA

    Directory of Open Access Journals (Sweden)

    Yogie Restu Firmansyah

    2017-01-01

    Full Text Available Effluen Instalasi Pengolahan Air Limbah (IPAL di Pabrik Tekstil X belum memenuhi kriteria yang ada, terutama untuk masalah warna. Sistem pengolahan IPAL menggunakan Anaerobic Biofilter memiliki kelebihan menyisihkan bahan organik yang tinggi, kebutuhan lahan yang relatif tidak besar, dan biaya operasi yang murah dibandingkan dengan sistem lumpur aktif yang menggunakan proses aerasi. Rotating Biological Contactor (RBC juga memiliki kelebihan yang sama dengan anaerobic biofilter. Perbandingan antara kedua sistem tersebut diperlukan untuk mengetahui sistem yang paling efektif untuk mengolah air limbah di Pabrik Textil X. Pengolahan adsorbsi batok arang kelapa dipilih untuk menghilangkan warna. Perencanaan ini dilakukan dengan menggunakan metode yang sistematis dimulai pengumpulan data primer dan sekunder yang berupa data karakteristik dan debit air limbah, lalu dilakukan perhitungan dan penggambaran Detail Engineering Desan (DED, volume pekerjaan dan Rancangan Anggaran Biaya (RAB, setelah itu dilakukan pembahasan untuk membandingkan kelebihan dan kekurangan dari unit anaerobic Biofilter yang dilengkapi adsorbsi arang batok kelapa dan Rotating Biological Contactor yang dilengkapi adsorbsi arang batok kelapa, lalu diambil kesimpulan dan saran yang relevan dengan tujuan dari perancanaan ini. Dari perhitungan DED didapat dimensi untuk masing masing unit IPAL sebagai berikut Bak ekualisasi (2,6 m x 2,6 m x 2 m, Septic tank (1,75 m x 1,5m x 2,5m, Anaerobic Filter 4 kompartemen (4,5m x 2,5m x 2,5m, , RBC 2 shaft  (2,75m x 2,75 m x 1m, Adsorbsi (3,5 mx 6,75m x 0,55m. Biaya investasi alternative 1 sebesar Rp   700.193.694,29, biaya operasi sebesar Rp 50.222.462,40, biaya perawatan sebesar Rp 3.495.000,00. Alternatif 2 biaya investasi sebesar Rp 777.526.655,53, biaya operasi sebesar Rp Rp 53.012.599,20  , biaya perawatan sebesar Rp 3.495.000,00. Kelebihan anaerobic filter adalah biaya investasi yang lebih kecil, kebutuhan lahan yang lebih sedikit yaitu

  20. Coal-packed methane biofilter for mitigation of green house gas emissions from coal mine ventilation air.

    Science.gov (United States)

    Limbri, Hendy; Gunawan, Cindy; Thomas, Torsten; Smith, Andrew; Scott, Jason; Rosche, Bettina

    2014-01-01

    Methane emitted by coal mine ventilation air (MVA) is a significant greenhouse gas. A mitigation strategy is the oxidation of methane to carbon dioxide, which is approximately twenty-one times less effective at global warming than methane on a mass-basis. The low non-combustible methane concentrations at high MVA flow rates call for a catalytic strategy of oxidation. A laboratory-scale coal-packed biofilter was designed and partially removed methane from humidified air at flow rates between 0.2 and 2.4 L min-1 at 30°C with nutrient solution added every three days. Methane oxidation was catalysed by a complex community of naturally-occurring microorganisms, with the most abundant member being identified by 16S rRNA gene sequence as belonging to the methanotrophic genus Methylocystis. Additional inoculation with a laboratory-grown culture of Methylosinus sporium, as investigated in a parallel run, only enhanced methane consumption during the initial 12 weeks. The greatest level of methane removal of 27.2±0.66 g methane m-3 empty bed h-1 was attained for the non-inoculated system, which was equivalent to removing 19.7±2.9% methane from an inlet concentration of 1% v/v at an inlet gas flow rate of 1.6 L min-1 (2.4 min empty bed residence time). These results show that low-cost coal packing holds promising potential as a suitable growth surface and contains methanotrophic microorganisms for the catalytic oxidative removal of methane.

  1. Coal-Packed Methane Biofilter for Mitigation of Green House Gas Emissions from Coal Mine Ventilation Air

    Science.gov (United States)

    Limbri, Hendy; Gunawan, Cindy; Thomas, Torsten; Smith, Andrew; Scott, Jason; Rosche, Bettina

    2014-01-01

    Methane emitted by coal mine ventilation air (MVA) is a significant greenhouse gas. A mitigation strategy is the oxidation of methane to carbon dioxide, which is approximately twenty-one times less effective at global warming than methane on a mass-basis. The low non-combustible methane concentrations at high MVA flow rates call for a catalytic strategy of oxidation. A laboratory-scale coal-packed biofilter was designed and partially removed methane from humidified air at flow rates between 0.2 and 2.4 L min−1 at 30°C with nutrient solution added every three days. Methane oxidation was catalysed by a complex community of naturally-occurring microorganisms, with the most abundant member being identified by 16S rRNA gene sequence as belonging to the methanotrophic genus Methylocystis. Additional inoculation with a laboratory-grown culture of Methylosinus sporium, as investigated in a parallel run, only enhanced methane consumption during the initial 12 weeks. The greatest level of methane removal of 27.2±0.66 g methane m−3 empty bed h−1 was attained for the non-inoculated system, which was equivalent to removing 19.7±2.9% methane from an inlet concentration of 1% v/v at an inlet gas flow rate of 1.6 L min−1 (2.4 min empty bed residence time). These results show that low-cost coal packing holds promising potential as a suitable growth surface and contains methanotrophic microorganisms for the catalytic oxidative removal of methane. PMID:24743729

  2. 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.)

  3. 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 ...

  4. 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

  5. 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.

  6. 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 ...

  7. 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...

  8. 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...

  9. 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 ...

  10. 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...

  11. 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...

  12. Assessing the Efficacy of the Aerobic Methanotrophic Biofilter in Methane Hydrate Environments

    Energy Technology Data Exchange (ETDEWEB)

    Valentine, David

    2012-09-30

    In October 2008 the University of California at Santa Barbara (UCSB) initiated investigations of water column methane oxidation in methane hydrate environments, through a project funded by the National Energy Technology Laboratory (NETL) entitled: assessing the efficacy of the aerobic methanotrophic biofilter in methane hydrate environments. This Final Report describes the scientific advances and discoveries made under this award as well as the importance of these discoveries in the broader context of the research area. Benthic microbial mats inhabit the sea floor in areas where reduced chemicals such as sulfide reach the more oxidizing water that overlies the sediment. We set out to investigate the role that methanotrophs play in such mats at locations where methane reaches the sea floor along with sulfide. Mats were sampled from several seep environments and multiple sets were grown in-situ at a hydrocarbon seep in the Santa Barbara Basin. Mats grown in-situ were returned to the laboratory and used to perform stable isotope probing experiments in which they were treated with 13C-enriched methane. The microbial community was analyzed, demonstrating that three or more microbial groups became enriched in methane?s carbon: methanotrophs that presumably utilize methane directly, methylotrophs that presumably consume methanol excreted by the methanotrophs, and sulfide oxidizers that presumably consume carbon dioxide released by the methanotrophs and methylotrophs. Methanotrophs reached high relative abundance in mats grown on methane, but other bacterial processes include sulfide oxidation appeared to dominate mats, indicating that methanotrophy is not a dominant process in sustaining these benthic mats, but rather a secondary function modulated by methane availability. Methane that escapes the sediment in the deep ocean typically dissolved into the overlying water where it is available to methanotrophic bacteria. We set out to better understand the efficacy of this

  13. Biofiltration of 1,1,1-trichloroethane by a trickle-bed air biofilter.

    Science.gov (United States)

    Lu, Chungsying; Chang, Kwotsair

    2003-09-01

    The performance of a trickle-bed air biofilter (TBAB) in the removal of 1,1,1-trichloroethane (TCLE) was evaluated in concentrations varying from 0.025 to 0.049 g/m3 and at empty-bed residence time (EBRT) varying from 20 to 90 s. Nearly complete TCLE removal could be achieved for influent carbon loading between 0.98 and 5.88 g/m3 h. The TBAB appeared efficient for controlling TCLE emission under low-carbon-loading conditions. Carbon recoveries higher than 95% were achieved, demonstrating the accuracy of results. The carbon mass rate of the liquid effluent was approximately two orders of magnitude less than that of the effluent CO2, indicating that dissolved TCLE and its derivatives in leachate were present in negligible amounts in the TBAB.

  14. Apparatus comprising trace element dosage and method for treating raw water in biofilter

    DEFF Research Database (Denmark)

    2015-01-01

    the inlet (2) to the outlet (3) or in the reverse direction, - the trace element dosage device (13) is positioned upstream of the porous filter material and microbial biomass and is configured to dose trace element(s) to the water flowing through the filter. A method for treating raw water by microbial......Apparatus for treating raw water in a biofilter The present invention relates to an apparatus in which raw water is treated through microbial activity where microbial activity is controlled by nutrients and other parameters. Some of the nutrients controlling the microbial activity are trace...... elements such as certain metals (Cu, Co, Cr, Mo, Ni, W, Zn or a mixture thereof). The apparatus comprising - a volume provided with an inlet (2) for raw water and an outlet (3) for water having been subjected to microbial activity, a filter and a trace element dosage device (13) are placed in this volume...

  15. Bacterial community structure of a full-scale biofilter treating pig house exhaust air

    DEFF Research Database (Denmark)

    Kristiansen, Anja; Pedersen, Kristina Hadulla; Nielsen, Per Halkjær

    2011-01-01

    Biological air filters represent a promising tool for treating emissions of ammonia and odor from pig facilities. Quantitative fluorescence in situ hybridization (FISH) and 16S rRNA gene sequencing were used to investigate the bacterial community structure and diversity in a full-scale biofilter ...... consisting of two consecutive compartments (front and back filter). The analysis revealed a highly specialized bacterial community of limited diversity, dominated by a few groups of Betaproteobacteria (especially Comamonas) and diverse Bacteroidetes. Actinobacteria, Gammaproteobacteria......, and betaproteobacterial ammoniaoxidizers (Nitrosomonas eutropha/Nitrosococcus mobilis-lineage) were also quantitatively important. Only a few quantitative differences existed between the two filter compartments at the group level, with a lower relative abundance of Actinobacteria and a higher relative abundance...

  16. Performance of a constructed wetland treating intensive shrimp aquaculture wastewater under high hydraulic loading rate

    International Nuclear Information System (INIS)

    Lin, Y.-F.; Jing, S.-R.; Lee, D.-Y.; Chang, Y.-F.; Chen, Y.-M.; Shih, K.-C.

    2005-01-01

    A water treatment unit, mainly consisting of free water surface (FWS) and subsurface flow (SF) constructed wetland cells, was integrated into a commercial-scale recirculating aquaculture system for intensive shrimp culture. This study investigated performance of the treatment wetlands for controlling water quality. The results showed that the FWS-SF cells effectively removed total suspended solids (55-66%), 5-day biochemical oxygen demand (37-54%), total ammonia (64-66%) and nitrite (83-94%) from the recirculating water under high hydraulic loading rates (1.57-1.95 m/day). This led to a water quality that was suitable for shrimp culture and effluent that always satisfied the discharge standards. The area ratios of wetlands to culture tank being demonstrated (0.43) and calculated (0.096) in this study were both significantly lower than the reported values. Accordingly, a constructed wetland was technically and economically feasible for managing water quality of an intensive aquaculture system. - A constructed wetland was found to be technically and economically feasible for managing water quality of an intensive recirculating aquaculture system

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

    Science.gov (United States)

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

    2018-06-15

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

  18. TECHNOLOGICAL ASPECTS OF PRODUCING POLYMERIC COMPOSITIONS FOR BIOFILTER WITH IMPROVED IMMOBILIZATION PROPERTIES

    Directory of Open Access Journals (Sweden)

    L. N. Studenikina

    2015-01-01

    Full Text Available As the material loading of the filters, it is recommended to use a polymer composition having high immobilization capacity. The introduction of the polyolefins natural polysaccharides attached polymer composition, the ability to retain on its surface microflora, and additional content in the composition of nutrients will ensure the maintenance of microbial life in the event of termination of enrolment in the biofilter nutrients. We have investigated the technological aspects of polymer compositions based on polyethylene (PE, containing natural polysaccharides starch and alkaline pulp (waste vegetable oil refining, in the ratio of 80 : 20 wt.%, when the processing in modern high-speed equipment. In the study of rheological indicators, it was found that contained in the cellulose fatty acid and wax soften the composition, where the effective viscosity is filled with PE with the use of cellulose is celebrated on 30 ÷ 35 % lower than the composition with starch. For polymer compositions containing as starch and cellulose, at a temperature of processing 200 °С observed fracture of flow curves, and when the critical temperature 220 °С there is a rapid release, followed by decomposition of the compositions. It is noted that the composition containing the cellulose has a higher porosity than containing starch, which facilitates immobilization of the microflora. For use as a load of biofilters more recommended songs based on PE and cellulose because they have superior immobilization due to their porous structure, and the presence in the composition of polysaccharides and nutrients, as evidenced development on the surface of the samples of the composition of microscopic fungi (Aspergillus, Penicillium.

  19. 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 ...

  20. 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