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Auteur (up) Auguet, J.C.; Montanie, H.; Delmas, D.; Hartmann, H.J.; Huet, V. doi  openurl
  Titre Dynamic of virioplankton abundance and its environmental control in the Charente estuary (France) Type Article scientifique
  Année 2005 Publication Revue Abrégée Microb Ecol  
  Volume 50 Numéro 3 Pages 337-349  
  Mots-Clés Bacteria/isolation & purification Ecosystem *Environment; Controlled France Plankton/*isolation & purification Rivers/chemistry/*microbiology Seasons Viruses/*isolation & purification Water Microbiology  
  Résumé The Charente River provides nutrient- and virus-rich freshwater input to the Marennes Oleron Basin, the largest oyster-producing region in Europe. To evaluate virioplankton distribution in the Charente Estuary and identify which environmental variables control dynamic of virioplankton abundance, five stations defined by a salinity gradient (0-0.5, 0.6-5, 13-17, 20-24, and higher than 30 PSU) were surveyed over a year. Viral abundance was related to bacterioplankton abundance and activities, photosynthetic pigments, nutrient concentration, and physical parameters (temperature and salinity). On a spatial scale, virus displayed a decreasing pattern seaward with abundance ranging over the sampling period from 1.4x10(7) to 20.8x10(7) viruses mL-1 making virioplankton the most abundant component of planktonic microorganisms in the Charente Estuary. A good correlation was found between viral and bacterial abundance (rs=0.85). Furthermore, bacterial abundance was the most important predictor of viral abundance explaining alone between 66% (winter) and 76% (summer) of viral variability. However, no relation existed between viral abundance and chlorophyll a. Temporal variations in viral distributions were mainly controlled by temperature through the control of bacterial dynamics. Spatial variations of viral abundance were influenced by hydrodynamic conditions especially during the winter season where virioplankton distribution was entirely driven by mixing processes.  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1296  
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Auteur (up) Auguet, J.C.; Montanie, H.; Lebaron, P. doi  openurl
  Titre Structure of virioplankton in the Charente Estuary (France): transmission electron microscopy versus pulsed field gel electrophoresis Type Article scientifique
  Année 2006 Publication Revue Abrégée Microb Ecol  
  Volume 51 Numéro 2 Pages 197-208  
  Mots-Clés Capsid/chemistry *Electrophoresis; Electron Plankton Rivers/*virology Seasons Seawater/*microbiology/*virology Viruses/genetics/*isolation & purification/ultrastructure *Water Microbiology; Gel; Pulsed-Field Environmental Monitoring/methods France Genome; Viral/genetics *Microscopy  
  Résumé Changes in the composition of viral communities were investigated along a salinity gradient and at different times by means of transmission electron microscopy (TEM) and pulsed field gel electrophoresis (PFGE). Samples were collected in fresh (Charente River), estuarine (Charente Estuary), and coastal (Pertuis d'Antioche, French Atlantic coast) waters. Both methods revealed similar patterns in viral community structure with a dominance of small viral particles (capsid and genome size). Viruses with a head size below 65 nm made up 71 +/- 5% of total virus-like particles, and virus-like genomes (VLG) below 100 kb accounted for 89 +/- 9% of total VLG. Despite this apparent stability of virioplankton composition over spatial scale (salinity gradient), the occurrence of large viruses (capsid and genome size) in estuarine and seawater samples indicated the presence of viral populations specific to a geographical location. Temporal changes in the structure (capsid and genome size) of viral communities were more pronounced than those reported at the spatial scale. From January to May 2003, seasonal changes in viral abundance and bacterial production occurred concomitantly with an increase in viral genomic diversity (richness), suggesting that virioplankton composition was strongly linked to changes in microbial activity and/or in the structure of the host communities. Although PFGE and TEM yielded complementary results in the description of virioplankton structures, it seems that the use of PFGE alone should be enough for the monitoring of community changes.  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1297  
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Auteur (up) Bessa, E.; Geffroy, B.; Gonçalves-De-Freitas, E. url  doi
openurl 
  Titre Tourism impact on stream fish measured with an ecological and a behavioural indicator Type Article scientifique
  Année 2017 Publication Revue Abrégée Aquatic Conserv: Mar Freshw Ecosyst  
  Volume Numéro Pages  
  Mots-Clés Behaviour; conservation evaluation; Environmental impact assessment; fish; recreation; river; stream  
  Résumé * As nature-based tourism grows, its impacts on aquatic ecosystems follow, requiring effective management techniques to conserve river integrity. Nevertheless, strong indicators of tourism impacts are scarce and have seldom been studied for many species. * This study evaluated whether microhabitat use and activity period of a variety of fish species are effective for assessing tourism impacts in a headwater stream in which recreation (snorkelling) occurs. Microhabitat use and activity period of the most representative fish were observed in river stretches used for recreation and compared with reference stretches. * Fish neither altered microhabitat use nor became more cryptic owing to tourism, maybe because they have evolved to occupy a certain microhabitat and cannot inhabit others, thus making habitat use a poor indicator of tourism impact. * Fish respond to the presence of tourists by changing the promptness to begin and end activity, making the time of activity a good indicator of tourism impact, which can be easily assessed by tourism managers or government agencies and used to control the environmental impact of recreation involving fish. * It is suggested that aquatic conservation protocols should include local indicators, and that behavioural indicators (activity period) might be more relevant than ecological indicators (microhabitat use) for early recognition of tourism impacts. These findings can be extended to the conservation of other fish communities subject to intensive tourism and with a strong circadian rhythm, such as coral reef fishes.  
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  Langue en Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 1099-0755 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2157  
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Auteur (up) Blanchet, M.; Pringault, O.; Panagiotopoulos, C.; Lefevre, D.; Charriere, B.; Ghiglione, J.-F.; Fernandez, C.; Aparicio, F.L.; Marrase, C.; Catala, P.; Oriol, L.; Caparros, J.; Joux, F. doi  openurl
  Titre When riverine dissolved organic matter (DOM) meets labile DOM in coastal waters: changes in bacterial community activity and composition Type Article scientifique
  Année 2017 Publication Revue Abrégée Aquat. Sci.  
  Volume 79 Numéro 1 Pages 27-43  
  Mots-Clés Bacterial community composition; bacterioplankton; biodegradation; carbon; coastal waters; Dissolved organic matter; Fluorescence; growth efficiency; lake water; marine; Mediterranean Sea; open-ocean; Priming effect; rhone river; terrestrial  
  Résumé Heterotrophic bacterial communities in marine environments are exposed to a heterogeneous mixture of dissolved organic compounds with different bioreactivity that may control both their activity and composition. The coastal environment is an example of a mixing area where recalcitrant allochthonous organic matter from rivers can encounter labile organic matter from marine phytoplanktonic blooms. The objective of this study was to explore the effects of mixed qualities of dissolved organic matter (DOM) on bacterial community activity (BCA) and bacterial community composition (BCC) and to test for a priming effect when DOM sources are added in combination. Coastal marine bacterial communities were incubated separately with a mixture of amino acids and with natural riverine DOM or with both sources together for 42 days. Addition of amino acids alone or in combination with riverine DOM led to a similar stimulation of BCA compared to control condition, whereas addition of riverine DOM alone did not modify BCA compared to the control. On the contrary, BCC analyzed by 16S rRNA gene pyrosequencing was not affected by the addition of amino acids alone, but changed dramatically with riverine DOM alone or in combination with amino acids. Our results show that changes in BCA and BCC can be driven by different types of DOM, but that these changes are not necessarily coupled. Moreover, the addition of labile DOM did not modify the microbial decomposition of riverine DOM, nor the BCC, suggesting that a priming effect did not occur under these experimental conditions.  
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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 1015-1621 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2090  
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Auteur (up) Brosse, S.; Beauchard, O.; Blanchet, S.; Dürr, H.H.; Grenouillet, G.; Hugueny, B.; Lauzeral, C.; Leprieur, F.; Tedesco, P.A.; Villeger, S.; Oberdorff, T. url  doi
openurl 
  Titre Fish-SPRICH: a database of freshwater fish species richness throughout the World Type Article scientifique
  Année 2013 Publication Revue Abrégée Hydrobiologia  
  Volume 700 Numéro 1 Pages 343-349  
  Mots-Clés Endemic; Global extent; Native; Non-native; River drainage basin; fishes  
  Résumé There is growing interest in large-scale approaches to ecology, for both plants and animals. In particular, macroecological studies enable examination of the patterns and determinants of species richness of a variety of groups of organism throughout the world, which might have important implications for prediction and mitigation of the consequences of global change. Here, we provide richness data for freshwater fishes, which, with more than 13,000 described species, comprise a quarter of all vertebrate species. We conducted an extensive literature survey of native, non-native (exotic), and endemic freshwater fish species richness. The resulting database, called Fish-SPRICH, contains data from more than 400 bibliographic sources including published papers, books, and grey literature sources. Fish-SPRICH contains richness values at the river basin grain for 1,054 river basins covering more than 80% of the earth's continental surface. This database is currently the most comprehensive global database of native, non-native and endemic freshwater fish richness available at the river basin grain.  
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  Auteur institutionnel Thèse  
  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 0018-8158 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 604  
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