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Auteur Goni-Urriza, M.; Moussard, H.; Lafabrie, H.; Carré, C.; Bouvy, M.; Sakka Hlaili, A.; Pringault, O. doi  openurl
  Titre Consequences of contamination on the interactions between phytoplankton and bacterioplankton Type Article scientifique
  Année 2018 Publication Revue Abrégée Chemosphere  
  Volume 195 Numéro Pages 212-222  
  Mots-Clés bizerte lagoon; bacterial communities; polycyclic aromatic-hydrocarbons; surface sediments; functional diversity; ecosystem; sediment resuspension; coastal lagoon; nutrient enrichment; tropical lagoon  
  Résumé Sediment resuspension can provoke strong water enrichment in nutrients, contaminants, and microorganisms. Microcosm incubations were performed in triplicate for 96 h, with lagoon and offshore waters incubated either with sediment elutriate or with an artificial mixture of contaminants issued from sediment resuspension. Sediment elutriate provoked a strong increase in microbial biomass, with little effects on the phytoplankton and bacterioplankton community structures. Among the pool of contaminants released, few were clearly identified as structuring factors of phytoplanktdn and bacterioplankton communities, namely simazine, Cu, Sn, Ni, and Cr. Effects were more pronounced in the offshore waters, suggesting a relative tolerance of the lagoon microbial communities to contamination. The impacts of contamination on the microbial community structure were direct or indirect, depending on the nature and the strength of the interactions between phytoplankton and bacterioplankton. (C) 2017 Elsevier Ltd. All rights reserved.  
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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 0045-6535 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2265  
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Auteur Sirot, C.; Darnaude, A.M.; Guilhaumon, F.; Ramos-Miranda, J.; Flores-Hernandez, D.; Panfili, J. url  doi
openurl 
  Titre Linking temporal changes in the demographic structure and individual growth to the decline in the population of a tropical fish Type Article scientifique
  Année 2015 Publication Revue Abrégée Estuarine, Coastal and Shelf Science  
  Volume 165 Numéro Pages 166-175  
  Mots-Clés American Silver Perch; model comparison; nursery; size distribution; somatic growth; Tropical lagoon  
  Résumé The exceptional biodiversity and productivity of tropical coastal lagoons can only be preserved by identifying the causes for the decline in the populations living in these vulnerable ecosystems. The Terminos lagoon in Mexico provided an opportunity for studying this issue as some of its fish populations, in particular the Silver Perch (Bairdiella chrysoura), have declined significantly since the 1980s. Fish sampling campaigns carried out over the whole lagoon area in 1979–81 and again in 2006–2011 revealed the mechanisms which may have been responsible for this decline. Based on biometrical data for 295 juveniles and adults from the two periods and on somatic growth derived from 173 otoliths, a study of the temporal changes in the demographic structure and life history traits (individual growth and body condition) made it possible to distinguish the causes of the decline in the B. chrysoura population. Growth models for the lagoon in 1980–1981 and 2006–2011 showed no significant change in the growth parameters of the population over the last 30 years with a logistic model giving an accurate estimate (R2 = 0.66) of the size-at-age for both periods. The decline in the B. chrysoura population could not be explained by an overall decrease in individual size and condition in the lagoon, the average standard length (SL) and Fulton index (FI) having increased slightly since 1980–1981 (4.6 mm and 0.02 for juveniles and 5.42 mm and 0.07 for adults). However, the size structure of the population in the lagoon has changed, with a significant shift in the size distribution of juveniles with a marked reduction in the proportion of juveniles ≤ 60 mm in the captures (90.9% fewer than in 1980–1981). As the otolith growth rate of fish during the first 4 months also decreased significantly between the two sampling periods (−15%), it is suggested that the main reason for the decline in the abundance and biomass of B. chrysoura within this system may be that its habitats are less suitable for fish growth and survival in the initial months after settlement. Environmental conditions in the lagoon appear to allow compensatory growth of the individuals that survive this early demographic bottleneck. The key for the conservation of B. chrysoura probably lies in the identification and restoration of the habitats required by its larvae and juveniles.  
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  Auteur institutionnel Thèse  
  Editeur 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 0272-7714 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1497  
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Auteur Sirot, C.; Villeger, S.; Mouillot, D.; Darnaude, A.M.; Ramos-Miranda, J.; Flores-Hernandez, D.; Panfili, J. url  doi
openurl 
  Titre Combinations of biological attributes predict temporal dynamics of fish species in response to environmental changes Type Article scientifique
  Année 2015 Publication Ecological Indicators Revue Abrégée  
  Volume 48 Numéro Pages 147-156  
  Mots-Clés Ecological and life-history traits; Environmental changes; Estuarine ecosystem; Multivariate index; Species sensitivity; Tropical lagoon  
  Résumé Assessing species vulnerability to environmental changes is a major challenge for conservation. Combinations of biological attributes have already been successfully used for this purpose, allowing large-scale prediction of inter-specific differences in demographic parameters (e.g. abundance) or endangered status. However, studies investigating whether biological attributes could be used to predict the temporal demographic responses of species in a changing environment are still scarce. In this work, we tackled this issue by taking advantage of a multi-decadal survey of concomitant changes in fish communities and environmental conditions within the Terminos lagoon (Mexico). Based on this rare dataset, we first characterized changes in abiotic parameters that occurred in this ecosystem since the 80s. Then, we adapted a multivariate index accounting for changes in both species abundance and occurrence to assess concomitant demographic changes for the 25 dominant fish species in the lagoon, classifying them into five various types of trajectories (“Increasing”, “Decreasing”, “Constant”, “Hump-shape” and “U-shape”). Finally, we assessed the accuracy in prediction of these temporal responses for all possible combinations of 15 biological attributes including taxonomy, ecological and life-history traits. Our results showed that fish specific demographic changes over the last 30 years could be accurately predicted (72% accuracy) using a combination of five biological attributes (spawning season, order, maximum salinity, width of salinity range, oocyte size) among which three could be related to the increase in average salinity occurred in the lagoon over this period. Appropriate sets of complementary biological attributes could similarly allow prediction of inter-specific differences in demographic changes in other areas, thereby offering an additional pragmatic tool for ecosystem managers to identify vulnerable species at the local scale.  
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  Auteur institutionnel Thèse  
  Editeur 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 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1112  
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