bascule de visibilité Search & Display Options

Tout Sélectionner    Désélectionner
 |   | 
Détails
   print
  Enregistrements Liens
Auteur Colin, N.; Villeger, S.; Wilkes, M.; de Sostoa, A.; Maceda-Veiga, A. doi  openurl
  Titre Functional diversity measures revealed impacts of non-native species and habitat degradation on species-poor freshwater fish assemblages Type Article scientifique
  Année 2018 Publication Revue Abrégée Sci. Total Environ.  
  Volume 625 Numéro (up) Pages 861-871  
  Mots-Clés biodiversity; ecosystems; community; life-history traits; Non-native species; 4th-corner problem; Functional diversity; Fish assemblages; Biomonitoring; ecological quality; flow regime; Human disturbance; mediterranean rivers; Mediterranean rivers; stream; traits-environment relationships  
  Résumé Trail-based ecology has been developed for decades lo infer ecosystem responses to stressors based on the functional structure of communities, yet its value in species-poor systems is largely unknown. Here, we used an extensive clataset in a Spanish region highly prone to non-native fish invasions (15 catchments, N 389 sites) to assess for the first time how species-poor communities respond to large-scale environmental gradients using a taxonomic and functional trait-based approach in riverine fish. We examined total species richness and three functional trait-based indices available when many sites have <= 3 species (specialization, FSpe; onginaliy, FOri and entropy, FEnt). We assessed the responses of these taxonomic and functional indices along gradients of altitude, water pollution, physical habitat degradation and non-native fish biomass. Whilst species richness was relatively sensitive to spatial effects, functional diversity indices were responsive across natural and anthropogenic gradients. All four diversity measures declined with altitude but this decline was modulated by physical habitat degradation (richness, FSpe and FEnt) and the non-native total fish biomass ratio (FSpe and FOri) in ways that varied between indices. Furthermore, FSpe and FOri were significantly correlated with Total Nitrogen. Non-native fish were a major component of the taxonomic and functional structure of fish communities, raising concerns about potential misdiagnosis between invaded and environmentally-degraded river reaches. Such misdiagnosis was evident in a regional fish index widely used in official monitoring programs. We recommend the application of FSpe and FOri to extensive clatasets from monitoring programs in order to generate valuable cross-system information about the impacts of non-native species and habitat degradation, even in species-poor systems. Scoring non-native species apart from habitat degradation in the indices used to determine ecosystem health is essential to develop better management strategies. (C) 2013 Elsevier B.V. All rights reserved.  
  Adresse  
  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 0048-9697 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2309  
Lien permanent pour cet enregistrement
 

 
Auteur Brouwer, G.M.; Duijnstee, I. a. P.; Hazeleger, J.H.; Rossi, F.; Lourens, L.J.; Middelburg, J.J.; Wolthers, M. doi  openurl
  Titre Diet shifts and population dynamics of estuarine foraminifera during ecosystem recovery after experimentally induced hypoxia crises Type Article scientifique
  Année 2016 Publication Revue Abrégée Estuar. Coast. Shelf Sci.  
  Volume 170 Numéro (up) Pages 20-33  
  Mots-Clés Bacteria; Benthic foraminifera; C-13 label; communities; Diet shifts; differential response; diversity; Hypoxia; in-situ; Intertidal; Macrofauna; Meiofauna; microphytobenthos carbon; population dynamics; Sediment  
  Résumé This study shows foraminiferal dynamics after experimentally induced hypoxia within the wider context of ecosystem recovery. C-13-labeled bicarbonate and glucose were added to the sediments to examine foraminiferal diet shifts during ecosystem recovery and test-size measurements were used to deduce population dynamics. Hypoxia-treated and undisturbed patches were compared to distinguish natural (seasonal) fluctuations from hypoxia-induced responses. The effect of timing of disturbance and duration of recovery were investigated. The foraminiferal diets and population dynamics showed higher fluctuations in the recovering patches compared to the controls. The foraminiferal diet and population structure of Haynesina germanica and Ammonia beccarii responded differentially and generally inversely to progressive stages of ecosystem recovery. Tracer inferred diet estimates in April and June and the two distinctly visible cohorts in the test-size distribution, discussed to reflect reproduction in June, strongly suggest that the ample availability of diatoms during the first month of ecosystem recovery after the winter hypoxia was likely profitable to A. beccarii. Enhanced reproduction itself was strongly linked to the subsequent dietary shift to bacteria. The distribution of the test dimensions of H. germanica indicated that this species had less fluctuation in population structure during ecosystem recovery but possibly reproduced in response to the induced winter hypoxia. Bacteria seemed to consistently contribute more to the diet of H. germanica than diatoms. For the diet and test-size distribution of both species, the timing of disturbance seemed to have a higher impact than the duration of the subsequent recovery period. (C) 2016 Published by Elsevier Ltd.  
  Adresse  
  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 0272-7714 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2065  
Lien permanent pour cet enregistrement
 

 
Auteur Legras, G.; Loiseau, N.; Gaertner, J.-C. doi  openurl
  Titre Functional richness: Overview of indices and underlying concepts Type Article scientifique
  Année 2018 Publication Revue Abrégée Acta Oecol.-Int. J. Ecol.  
  Volume 87 Numéro (up) Pages 34-44  
  Mots-Clés biodiversity; community composition; diversity indexes; ecology; ecosystem processes; fish communities; Functional richness indices; Guidelines; Index properties; intraspecific trait variation; Limitations; phylogenetic diversity; species richness; variability  
  Résumé Functional richness, currently defined as the amount of niche space occupied by the species within a community, is one of the three major components of functional diversity. Different indices have been developed in order to quantify this component. However, the range of indices available for assessing functional richness, often mathematically complex and based on different rationales, can cause confusion for field ecologists and lead to misinterpretation of the results obtained. In this context, we have provided the first study exclusively focused on the comparison of the definitions, advantages and drawbacks of a large set of functional richness indices. The first part of this work is focused on four indices (FDP&G, FRic, TOP and N-hypervolumes indices) that are currently the most commonly used for assessing functional richness. We have completed our study by including recently developed indices that enable us to take into account the intraspecific trait variability (i.e. FRim index and TDP framework), because there is currently a growing scientific consensus regarding the necessity of including this aspect in the assessment of the functional diversity of communities. We demonstrate that although authors have argued that their index describes the functional richness, each of them describes only part of it, and this part may strongly differ from one index to another. Rather than advocating the general use of a single index and/or systematically avoiding others, our study highlights the need for selecting indices in close relation with the context, the available data and the aims of each study. Such a strategy is an essential preliminary step for preventing misunderstanding and artefactual controversies. Along these lines, we propose some guidelines to help users in selecting the most appropriate indices according both to the facet of functional richness on which they wish to focus and to the characteristics of the available data.  
  Adresse  
  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 1146-609x ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2323  
Lien permanent pour cet enregistrement
 

 
Auteur Brehmer, P.; Laugier, T.; Kantoussan, J.; Galgani, F.; Mouillot, D. url  doi
openurl 
  Titre Does coastal lagoon habitat quality affect fish growth rate and their recruitment? Insights from fishing and acoustic surveys Type Article scientifique
  Année 2013 Publication Revue Abrégée Estuar. Coast. Shelf Sci.  
  Volume 126 Numéro (up) Pages 1-6  
  Mots-Clés Ecotoxicity; amphidromous; diversity; estuarine; exploitation; fish; habitat quality; indicators; lagoon; management; multibeam sonar; shallow water; size; target strength; thau lagoon; winter flounder  
  Résumé Ensuring the sustainability of fish resources necessitates understanding their interaction with coastal habitats, which is becoming ever more challenging in the context of ever increasing anthropogenic pressures. The ability of coastal lagoons, exposed to major sources of disturbance, to provide resources and suitable habitats for growth and survival of juvenile fish is especially important. We analysed three lagoons with different ecological statuses and habitat quality on the basis of their eutrophication and ecotoxicity (Trix test) levels. Fish abundances were sampled using fishing and horizontal beaming acoustic surveys with the same protocols in the same year. The relative abundance of Anguilla anguilla, Dicentrarchus labrax or the Mugilidae group was not an indicator of habitat quality, whereas Atherina boyeri and Sparus aurata appeared to be more sensitive to habitat quality. Fish abundance was higher in the two lagoons with high eutrophication and ecotoxicity levels than in the less impacted lagoon, while fish sizes were significantly higher in the two most severely impacted lagoons. This leads us to suggest low habitat quality may increase fish growth rate (by the mean of a cascading effect), but may reduce lagoon juvenile abundance by increasing larval mortality. Such a hypothesis needs to be further validated using greater investigations which take into account more influences on fish growth and recruitment in such variable environments under complex multi-stressor conditions. (C) 2013 Elsevier Ltd. All rights reserved.  
  Adresse  
  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 0272-7714 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 535  
Lien permanent pour cet enregistrement
 

 
Auteur Coll, M.; Steenbeek, J. doi  openurl
  Titre Standardized ecological indicators to assess aquatic food webs: The ECOIND software plug-in for Ecopath with Ecosim models Type Article scientifique
  Année 2017 Publication Revue Abrégée Environ. Modell. Softw.  
  Volume 89 Numéro (up) Pages 120-130  
  Mots-Clés biodiversity; Conservation; Ecological standardized indicators; Ecopath with Ecosim; ecospace; Ecosystem indicators; Environmental status; Fisheries management; Food web models; impacts; index; marine ecosystems; Mediterranean Sea; network analysis; ocean; Software plug-in  
  Résumé Ecological indicators are useful tools to analyse and communicate historical changes in ecosystems and plausible future scenarios while evaluating environmental status. Here we introduce a new plug-in to the Ecopath with Ecosim (EwE) food web modelling approach, which is widely used to quantitatively describe aquatic ecosystems. The plug-in (ECOIND) calculates standardized ecological indicators. We describe the primary functionality of ECOIND and provide an example of its application in both static and temporal-spatial dynamic modelling, while we highlight several related features including a new taxonomy input database (species traits) and the ability to analyse input uncertainty on output results. ECOIND adds new capabilities to the widely used EwE food web modelling approach and enables broadening its applications into biodiversity and conservation-based frameworks to contribute to integrated ecosystem analyses. (C) 2016 Elsevier Ltd. All rights reserved.  
  Adresse  
  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 1364-8152 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2088  
Lien permanent pour cet enregistrement
Tout Sélectionner    Désélectionner
 |   | 
Détails
   print

Save Citations:
Export Records: