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Auteur (up) Leboulanger, C.; Bouvy, M.; Pagano, M.; Dufour, R.A.; Got, P.; Cecchi, P. url  doi
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  Titre Responses of Planktonic Microorganisms from Tropical Reservoirs to Paraquat and Deltamethrin Exposure Type Article scientifique
  Année 2009 Publication Revue Abrégée Arch. Environ. Contam. Toxicol.  
  Volume 56 Numéro 1 Pages 39-51  
  Mots-Clés communities; cylindrospermopsis-raciborskii; fluorescence; herbicides; insecticides; lake guiers; solid-phase extraction; toxicity; water; west-africa  
  Résumé This study focused on the effects of two pesticides, paraquat (herbicide) and deltamethrin (insecticide), which are two common molecules used intensively in Burkina Faso. Natural bacterial populations, phytoplankton cultures (one cyanobacterium, Cylindrospermopsis raciborskii, and one chlorophycea, Monoraphidium sp.), and two species of zooplankton (Diaphanosoma excisum and Moina micrura) were isolated from aquatic communities and were used as biological targets in the experimental protocols. Paraquat was moderately toxic to bacteria and phytoplankton, whereas deltamethrin was significantly toxic only to the zooplankton species. Paradoxically, the chlorophycea Monoraphidium sp. exhibited a significant increase of in vitro fluorescence after 48 h at the highest doses. Preliminary tests were also performed from natural water extract of the main drinking water supply of the country (Loumbila Reservoir) by using solid-phase extraction. Obviously, the natural extract proved to be toxic to the same biological targets. Despite the absence of any determination of pesticides in the natural extract, the question of contamination and toxicity of these waters affects concerns about the safety of water supply and the effect of human pressure on the dynamics of planktonic communities of freshwater reservoirs in arid regions of western Africa.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0090-4341 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 819  
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Auteur (up) Pringault, O.; Lafabrie, C.; Avezac, M.; Bancon-Montigny, C.; Carré, C.; Chalghaf, M.; Delpoux, S.; Duvivier, A.; Elbaz-Poulichet, F.; Gonzalez, C.; Got, P.; Leboulanger, C.; Spinelli, S.; Hlaili, A.S.; Bouvy, M. doi  openurl
  Titre Consequences of contaminant mixture on the dynamics and functional diversity of bacterioplankton in a southwestern Mediterranean coastal ecosystem Type Article scientifique
  Année 2016 Publication Revue Abrégée Chemosphere  
  Volume 144 Numéro Pages 1060-1073  
  Mots-Clés aquatic systems; Bacterial growth efficiency; Bacterial production; bizerte lagoon; Community level physiological profiles; growth efficiency; Herbicides; heterotrophic bacteria; Metals; microbial communities; Microcosms; organic-carbon; polycyclic aromatic-hydrocarbons; sediment resuspension; substrate utilization pattern; surface sediments  
  Résumé Contamination of coastal environments is often due to a complex mixture of pollutants, sometimes in trace levels, that may have significant effects on diversity and function of organisms. The aim of this study was to evaluate the short-term dynamics of bacterioplankton exposed to natural and artificial mixtures of contaminants. Bacterial communities from a southwestern Mediterranean ecosystem, lagoon and the bay (offshore) of Bizerte were exposed to i) elutriate from resuspension of contaminated sediment, and ii) an artificial mixture of metals and herbicides mimicking the contamination observed during sediment resuspension. Elutriate incubation as well as artificial spiking induced strong enrichments in nutrients (up to 18 times), metals (up to six times) and herbicides (up to 20 times) relative to the in situ concentrations in the offshore station, whereas the increases in contaminants were less marked in the lagoon station. In the offshore waters, the artificial mixture of pollutants provoked a strong inhibition of bacterial abundance, production and respiration and significant modifications of the potential functional diversity of bacterioplankton with a strong decrease of the carbohydrate utilization. In contrast, incubation with elutriate resulted in a stimulation of bacterial activities and abundances, suggesting that the toxic effects of pollutants were modified by the increase in nutrient and DOM concentrations due to the sediment resuspension. The effects of elutriate and the artificial mixture of pollutants on bacterial dynamics and the functional diversity were less marked in the lagoon waters, than in offshore waters, suggesting a relative tolerance of lagoon bacteria against contaminants. (C) 2015 Elsevier Ltd. All rights reserved.  
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  Editeur Lieu de Publication Éditeur  
  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0045-6535 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1507  
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