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Auteur Mullon, C.; Shin, Y.-J.; Cury, P. doi  openurl
  Titre Neats : a Network Economics Approach to Trophic Systems Type Article scientifique
  Année 2009 Publication Revue Abrégée Ecol. Model.  
  Volume Numéro Pages 13-p.  
  Mots-Clés economic equilibrium; food web; marine ecosystems; variational inequality  
  Résumé The main principle of the economic approach to a trophic system we propose here lies in assuming that there is a transfer of food along a path between a prey and a predator if, for the predator, the benefits are greater than costs of predation on this path. Conversely, if the costs exceed the benefits, there are no flows. This trade-off, considered all along the food chains of an ecosystem, together with ecological processes (assimilation, somatic maintenance) results in a model coupling mass balance equations (biological constraints) and complementarity principles (Walras’ law). Here is the core of the Network Economics Approach to Trophic Systems (NEATS). We illustrate with simple examples of ecosystems how these principles result in algebraic equations which can be analyzed mathematically and solved numerically.We show, in amore sophisticated example of an input/output trophic network, that they result in “affine variational inequalities”, whose solutions can be estimated. We make explicit how the approach can be applied to address ecological questions, concerning differences of productivity, causes of biological diversity, or the nature of controls in marine ecosystems.

© 2009 Elsevier B.V. All rights reserved.
 
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  Langue Eng Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
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  ISSN 0304-3800 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 46  
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Auteur Pethybridge, H.; BODIN, N.; Arsenault-Pernet, E.-J.; BOURDEIX, J.-H.; BRISSET, B.; BIGOT, J.-L.; ROOS, D.; Peter, M. url  openurl
  Titre Temporal and inter-specific variations in forage fish feeding conditions in the NW Mediterranean: lipid content and fatty acid compositional changes Type Article scientifique
  Année 2014 Publication Revue Abrégée Marine Ecology Progress Series  
  Volume 512 Numéro Pages 39-54  
  Mots-Clés Clupeiformes; ecosystem health; Environmental variations; Nutritional condition; Prey Quality; Trophic markers  
  Résumé We describe the total lipid content, lipid class composition and fatty acid profiles of adult forage fishes (anchovy, sardine and sprat) sampled in the NW Mediterranean Sea in 2010 and 2011. Inter-and intra-species differences were mostly related to sampling period with limited effect of gender or total length. As an assemblage, total lipid content and relative levels of triacylglycerols and fatty acids 16:1n7, 20:5n3 and 14:0 in forage fish were highest in summer and autumn, indicating better feeding conditions and a more pronounced diatom-supported food web. In contrast, total lipid content was lowest at the end of winter and spring, and coincided with high levels of 22:6n3, indicating a more herbivorous diet based on dinoflagellates. Resource partitioning and niche separation, as inferred from fatty acid profiles, were apparent between species. Sardine showed a more diverse, temporally separated feeding strategy than anchovy, and dietary overlap was higher in winter than summer with sardine having higher markers of copepods, 22:1n11 and 20:1n9. Sprat collected in winter occupied a separate niche area to both sardine and anchovy with higher total lipid content and carnivory biomarker 18:1n9. Our results show that the lipid dynamics of forage fishes can be used to gain quantitative insights into sub-system level changes in species interactions, including prey and predator productivity.  
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  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0171-8630 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1129  
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Auteur ROQUE D'ORBCASTEL, E.; BLANCHETON, J.-P.; BELAUD, A. url  openurl
  Titre Water quality and rainbow trout performance in a Danish Model Farm recirculating system: Comparison with a flow through system Type Article scientifique
  Année 2009 Publication Aquacultural Engineering Revue Abrégée  
  Volume 40 Numéro 3 Pages 135-143  
  Mots-Clés Energy cost; Water quality; Flow rate; Treatment system; Performance; Trout; Recirculating system  
  Résumé The objective was to compare water quality and fish growth and mortality in a pilot scale recirculating system (RS) and a control tank in flow through system (FTS). The RS was designed after the Danish Model Trout Farm and operated with a make Lip Water renewal rate of 9 m(3) kg(-1) of fish produced. RS water quality did not decrease significantly with water flow rate decrease in the RS. During the experiment, the RS water treatment system presented solids removal efficiency of 59.6 +/- 27.7% d(-1), ammonia oxidation of 45 +/- 32 g m(-3) d(-1), oxygenation yield of 392 +/- 132 g of O-2 kWh(-1) and CO2 degassing of 23.3 +/- 11.9% pass(-1). In the RS, nitrite concentration was 0.15 +/- 0.07 mg l(-1), close to the toxicity threshold; a N-2 supersaturation phenomenon was measured, probably due to the air injection depth. The biofilter and sedimentation area management has to be improved to avoid Organic matter decomposition and release of dissolved elements. Even if no N-2 over-saturation apparent effect on fish performance and aspect were detected, the airlift depth has to be modified in the case of industrial development of the RS. Some improvements of the water treatment system, especially on the airlift and sedimentation area, are suggested. Concerning fish growth, no significant differences were observed between the RS and the FTS. No pathologies were detected and cumulative mortality rates (0.1%) were similar to the farm's Usual data. There were no significant effects of water flow rate decrease in the RS on fish performance and energy savings were recorded to be 0.7 kWh kg(-1) of fish produced between RS1 and RS2. The global energy cost of the RS was 3.56 kWh kg(-1) of fish produced (0.107 (sic) kg(-1) of fish produced). Even if the energy consumption of the water treatment system can be improved, the results confirm that recirculating system can be used for industrial trout On growing, without fish performance deterioration. (C) 2009 Elsevier B.V. All rights reserved.  
  Adresse Ecole Natl Super Agron Toulouse, ENSAT, F-31326 Castanet Tolosan, France.  
  Auteur institutionnel Thèse  
  Editeur Elsevier Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0144-8609 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 6506 collection 1227  
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Auteur ROQUE D'ORBCASTEL, E.; LEMARIE, G.; BREUIL, G.; PETOCHI, T.; MARINO, G.; TRIPLET, S.; DUTTO, G.; FIVELSTAD, S.; COEURDACIER, J.-L.; BLANCHETON, J.-P. url  openurl
  Titre Effects of rearing density on sea bass (Dicentrarchus labrax) biological performance, blood parameters and disease resistance in a flow through system Type Article scientifique
  Année 2010 Publication Aquatic Living Resources Revue Abrégée  
  Volume 23 Numéro 1 Pages 109-117  
  Mots-Clés Rearing density; Flow through system; Stress; Water quality; Sea bass  
  Résumé During 84 days, the effects of density on juvenile sea bass (Dicentrarchus labrax) (76 +/- 16 g) were studied in an experimental tank-based flow through system. Performance, stress response and resistance to virus infection were analysed under five stabilized rearing densities: 10, 20, 40, 70 and 100 kg m(-3). Water quality parameters (CO2, total ammonia nitrogen and O-2) were measured and maintained close to the recommended values for farmed sea bass by adjusting water renewal exchange. No significant differences were observed between density treatments, neither on stress response (cortisol) nor susceptibility to nodavirus. With regards to biological performances, the daily feed intake and specific growth rate were significantly lower in fish reared at the 100 kg m(-3) density. Results on the effects of density in sea bass reared in flow through (present study) and in recirculating aquaculture systems (RAS) (Sammouth et al. 2009) were compared as a contribution to the identification of density not affecting health and welfare in farmed sea bass.  
  Adresse Bergen Univ Coll, N-5020 Bergen, Norway.  
  Auteur institutionnel Thèse  
  Editeur EDP Sciences Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0990-7440 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 11287 collection 1221  
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Auteur Said, O.B.; Louati, H.; Soltani, A.; Preud’homme, H.; Cravo-Laureau, C.; Got, P.; Pringault, O.; Aissa, P.; Duran, R. url  doi
openurl 
  Titre Changes of benthic bacteria and meiofauna assemblages during bio-treatments of anthracene-contaminated sediments from Bizerta lagoon (Tunisia) Type Article scientifique
  Année 2015 Publication Revue Abrégée Environ Sci Pollut Res  
  Volume 22 Numéro 20 Pages 15319-15331  
  Mots-Clés Anthracene; Atmospheric Protection/Air Quality Control/Air Pollution; Bacteria diversity; Bioremediation; Bizerta lagoon; Community structure; Degradation; Ecotoxicology; Environmental Chemistry; Environmental Health; Environment, general; Meiofauna; Microcosms; PAH degraders; Waste Water Technology / Water Pollution Control / Water Management / Aquatic Pollution  
  Résumé Sediments from Bizerta lagoon were used in an experimental microcosm setup involving three scenarios for the bioremediation of anthracene-polluted sediments, namely bioaugmentation, biostimulation, and a combination of both bioaugmentation and biostimulation. In order to investigate the effect of the biotreatments on the benthic biosphere, 16S rRNA gene-based T-RFLP bacterial community structure and the abundance and diversity of the meiofauna were determined throughout the experiment period. Addition of fresh anthracene drastically reduced the benthic bacterial and meiofaunal abundances. The treatment combining biostimulation and bioaugmentation was most efficient in eliminating anthracene, resulting in a less toxic sedimentary environment, which restored meiofaunal abundance and diversity. Furthermore, canonical correspondence analysis showed that the biostimulation treatment promoted a bacterial community favorable to the development of nematodes while the treatment combining biostimulation and bioaugmentation resulted in a bacterial community that advantaged the development of the other meiofauna taxa (copepods, oligochaetes, polychaetes, and other) restoring thus the meiofaunal structure. The results highlight the importance to take into account the bacteria/meiofauna interactions during the implementation of bioremediation treatment.  
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  ISSN 0944-1344, 1614-7499 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1415  
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