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Building functional groups of marine benthic macroinvertebrates on the basis of general community assembly mechanisms
article dans des revues - 2017-03
Alexandridis, Nikolaos, et al.
Titre Building functional groups of marine benthic macroinvertebrates on the basis of general community assembly mechanisms Type d'√©tude article dans des revues Auteurs personnes Alexandridis Nikolaos Auteur Bacher C√©dric Auteur Desroy Nicolas Auteur Jean Fred Auteur Date de publication 2017-03 Editeur(s) [S.l.] : Elsevier Journal of Sea Research, ISSN 1385-1101 vol.121 R√©sum√© The accurate reproduction of the spatial and temporal dynamics of marine benthic biodiversity requires the development of mechanistic models, based on the processes that shape macroinvertebrate communities. The modelled entities should, accordingly, be able to adequately represent the many functional roles that are performed by benthic organisms. With this goal in mind, we applied the emergent group hypothesis (EGH), which assumes functional equivalence within and functional divergence between groups of species. The first step of the grouping involved the selection of 14 biological traits that describe the role of benthic macroinvertebrates in 7 important community assembly mechanisms. A matrix of trait values for the 240 species that occurred in the Rance estuary (Brittany, France) in 1995 formed the basis for a hierarchical classification that generated 20 functional groups, each with its own trait values. The functional groups were first evaluated based on their ability to represent observed patterns of biodiversity. The two main assumptions of the EGH were then tested, by assessing the preservation of niche attributes among the groups and the neutrality of functional differences within them. The generally positive results give us confidence in the ability of the grouping to recreate functional diversity in the Rance estuary. A first look at the emergent groups provides insights into the potential role of community assembly mechanisms in shaping biodiversity patterns. Our next steps include the derivation of general rules of interaction and their incorporation, along with the functional groups, into mechanistic models of benthic biodiversity. Cat√©gories th√©matiques benthos√©cosyst√®me benthiquedomaine benthiquemod√®le de comportementestuairediversit√© biologique Mots-cl√©s libres Assembly mechanisms/Benthic communities/Biological traits/Emergent groups/estuaire de la Rance/estuary/flore benthique/Functional diversity/Functional redundancy Echelle de territoire bassins versants Bassin(s) versant(s) Rance - Faluns Note DOI = 10.1016/j.seares.2017.01.007 Langue(s) Anglais Format p59 √† p70 Document en ligne https://www.sciencedirect.com/science/article/pii/S1385110116300508 N¬į d'√©dition (ISBN, DOI,...) 10.1016/j.seares.2017.01.007 Permalink http://etudes.bretagne-environnement.org/index.php?lvl=notice_display&id=159810Fish community responses to green tides in shallow estuarine and coastal areas
article dans des revues - 2016-03-31
Le Luherne, E., et al.
Titre Fish community responses to green tides in shallow estuarine and coastal areas Type d'√©tude article dans des revues Auteurs personnes Le Luherne E. Auteur Reveillac E. Auteur PONSERO A. Auteur Sturbois, Anthony Auteur Ballu S. Auteur PERDRIAU M Auteur Le Pape, O. Auteur Date de publication 2016-03-31 Editeur(s) [S.l.] : Elsevier Revue Estuarine, Coastal and Shelf Science, ISSN 0272-7714 n¬į175 R√©sum√© ¬© r√©sum√© √©diteur :
"All over the world, numerous bays and estuarine systems that are known to shelter essential fish habitats are experiencing proliferations of green macroalgae known as green tides. Although the processes that enhance green tides in response to nutrient enrichment are well known, their consequences for ecological communities despecially for ichthyofauna remain poorly studied. To estimate these consequences, this analysis focused on the two types of shallow systems that are experiencing green tides: sandy beaches and estuarine mudflats. In these two systems, macroalgae proliferation and fish community were surveyed along seasonal cycles at control and impacted sites that shared similar physico-chemical parameters and sediment structure. To analyse the consequences of green tides on the fish community, a Before-After Control-Impact approach was used. This approach reveals no difference between fish communities at the control and impacted sites before the macroalgal bloom. Then, it underlines an influence of green tides on the fish community, and this influence varies according to the composition, density and duration of the macroalgal bloom. Indeed, when intertidal systems experienced short proliferation and/or weak density, green tides did not seem to impact the fish community. How-ever, when green macroalgae proliferated in large quantities and/or when the proliferation lasted for long periods, the fish community was significantly affected. These modifications in the fish community led to a significant decrease in fish species diversity and density until fish disappeared from impacted sites at high proliferations. Furthermore, the response of fish species to green tides differed according to their functional guilds. Negative consequences for benthic and marine juvenile fish species were beginning at low proliferations, whereas for pelagic fish species they occurred only at high proliferations. Thus, green tides significantly affect fish habitat suitability because they lead to changes in the composition of the fish community and eventually to the local disappearance of fish at high proliferations."
Cat√©gories th√©matiques mar√©e vertealgueprolif√©ration d'algueseutrophisationpoissonsableestuairebouevase Mots-cl√©s libres Fish community/Sandy beaches and estuarine mudflats/Green tides/Macroalgae/Nursery/Sandy beach and estuarine mudflat/Green tide/estuary/estuaire de la Rance Echelle de territoire baies et rades Note DOi = doi:10.1016/j.ecss.2016.03.031
Article de la revue "Estuarine, Coastal and Shelf Science" √©dit√©e par Elsevier (ISSN 0272-7714) vol.175 paru en 2016, pp 79-92.
Notice sur ScienceDirect = http://www.sciencedirect.com/science/article/pii/S0272771416300981
Texte int√©gral = http://www.reservebaiedesaintbrieuc.com/wp-content/IMG/pdf/publication/etudes_scientifiques/LeLuherne2016.pdf
Langue(s) Anglais Format p79 √† p92 Document en ligne http://www.reservebaiedesaintbrieuc.com/wp-content/IMG/pdf/publication/etudes_scientifiques/LeLuherne2016.pdf N¬į d'√©dition (ISBN, DOI,...) doi:10.1016/j.ecss.2016.03.031 Permalink http://etudes.bretagne-environnement.org/index.php?lvl=notice_display&id=155240High alkaline phosphatase activity in phosphate replete waters: The case of two macrotidal estuaries
article dans des revues - 2016-07
Labry, Claire, et al.
Titre High alkaline phosphatase activity in phosphate replete waters: The case of two macrotidal estuaries Type d'√©tude article dans des revues Auteurs personnes Labry Claire Auteur Delmas Daniel Auteur Youenou Agnes Auteur Qu√©r√© Julien Auteur LEYNAERT Aude Auteur Fraisse Stephane Auteur Raimonet M√©lanie Auteur RAGUENEAU Olivier Auteur Date de publication 2016-07 Editeur(s) [S.l.] : Association for the Sciences of Limnology and Oceanography
[S.l.] : Wiley
Revue Limnology and Oceanography, ISSN 0024-3590 vol.61 n¬į4 R√©sum√© The occurrence of alkaline phosphatase activity (APA) that hydrolyses organic phosphorus into phosphate (PO4) is commonly related to PO4 deficiency of oceanic, coastal and fresh waters. APA is almost never investigated in PO4-rich estuaries, since very low activities are expected to occur. As a consequence, microbial mineralization of organic phosphorus into PO4 has often been ignored in estuaries. In this study, we examined the importance of potential APA and the associated microbial dynamics in two estuaries, the Aulne and the Elorn (Northwestern France), presenting two different levels of PO4 concentrations. Unexpected high potential APA was observed in both estuaries. Values ranged from 50 to 506 nmol L‚ąí1 h‚ąí1, which range is usually found in very phosphorus-limited environments. High potential APA values were observed in the oligohaline zone (salinity 5‚Äď15) in spring and summer, corresponding to a PO4 peak and a maximum bacterial production of particle-attached bacteria. In all cases, high potential APA was associated with high suspended particulate matter and total particulate phosphorus. The low contribution of the 0.2‚Äď1 őľm fraction to total APA, the strong correlation between particulate APA and bacterial biomass, and the close relationship between the production of particle-attached bacteria and APA, suggested that high potential APA is mainly due to particle-attached bacteria. These results suggest that the microbial mineralization of organic phosphorus may contribute to an estuarine PO4 production in spring and summer besides physicochemical processes. Cat√©gories th√©matiques estuairephosphore Mots-cl√©s libres alkaline phosphatase/alkaline phosphatase activity (APA)/estuary/phosphatase/phosphatase alcaline/estuaire de l'Aulne/estuaire de l'Elorn Echelle de territoire baies et rades Note DOI = 10.1002/lno.10315 Langue(s) Anglais Format 1513-1529 Document en ligne http://onlinelibrary.wiley.com/doi/10.1002/lno.10315/abstract Localisation du document http://archimer.ifremer.fr/doc/00337/44840/44428.pdf N¬į d'√©dition (ISBN, DOI,...) 10.1002/lno.10315 Permalink http://etudes.bretagne-environnement.org/index.php?lvl=notice_display&id=159712Environmental factors affecting maerl bed structure in Brittany (France)
article dans des revues - 2015
Dutertre, Micka√ęl, et al.
Titre Environmental factors affecting maerl bed structure in Brittany (France) Type d'√©tude article dans des revues Auteurs personnes Dutertre Micka√ęl Auteur Grall Jacques Auteur Ehrhold Axel Auteur Hamon Dominique Auteur Date de publication 2015 Editeur(s) [S.l.] : British Phycological Society
[S.l.] : Taylor & Francis
European Journal of Phycology, ISSN 0967-0262 vol.50 n¬į4 R√©sum√© ¬© r√©sum√© auteurs :
"This study used a large spatial scale approach in order to better quantify the relationships between maerl bed structure and a selection of potentially forcing physical factors. Data on maerl bed structure and morpho-sedimentary characteristics were obtained from recent oceanographic surveys using underwater video recording and grab sampling. Considering the difficulties in carrying out real-time monitoring of highly variable hydrodynamic and physicochemical factors, these were generated by three-dimensional numerical models with high spatial and temporal resolution. The BIOENV procedure indicated that variation in the percentage cover of thalli can best be explained (correlation = 0.76) by a combination of annual mean salinity, annual mean nitrate concentration and annual mean current velocity, while the variation in the proportion of living thalli can best be explained (correlation = 0.47) by a combination of depth and mud content. Linear relationships showed that the percentage cover of maerl thalli was positively correlated with nitrate concentration (R2 = 0.78, P < 0.01) and negatively correlated with salinity (R2 = 0.81, P < 0.01), suggesting a strong effect of estuarine discharge on maerl bed structure, and also negatively correlated with current velocity (R2 = 0.81, P < 0.01). When maerl beds were deeper than 10 m, the proportion of living thalli was always below 30% but when they were shallower than 10 m, it varied between 4 and 100%, and was negatively correlated with mud content (R2 = 0.53, P < 0.01). On the other hand, when mud content was below 10%, the proportion of living thalli showed a negative correlation with depth (R2 = 0.84, P < 0.01). This large spatial scale explanation of maerl bed heterogeneity provides a realistic physical characterization of these ecologically interesting benthic habitats and usable findings for their conservation and management."
Cat√©gories th√©matiques estuairebenthosdomaine benthique√©cosyst√®me benthiqueflore Mots-cl√©s libres Benthic habitats/Brittany/environmental factors/estuary/flore benthique/large spatial scale/maerl/ma√ęrl/facteur environnemental/facteurs environnementaux/habitat benthique Echelle de territoire r√©gion (ou supra) Note DOI = 10.1080/09670262.2015.1063698
Notice sur le site √©diteur Taylor & Francis = http://dx.doi.org/10.1080/09670262.2015.1063698
Notice Archimer = http://archimer.ifremer.fr/doc/00280/39089/
Document en texte int√©gral = http://archimer.ifremer.fr/doc/00280/39089/37816.pdf
Langue(s) Anglais Format pp371-383 Document en ligne http://archimer.ifremer.fr/doc/00280/39089/ Localisation du document http://archimer.ifremer.fr/doc/00280/39089/37816.pdf N¬į d'√©dition (ISBN, DOI,...) 10.1080/09670262.2015.1063698 Permalink http://etudes.bretagne-environnement.org/index.php?lvl=notice_display&id=158086An integrated environmental approach to investigate biomarker fluctuations in the blue mussel Mytilus edulis L. in the Vilaine estuary, France.
article dans des revues - 2013-02
Farcy, Emilie, et al.
Titre An integrated environmental approach to investigate biomarker fluctuations in the blue mussel Mytilus edulis L. in the Vilaine estuary, France. Type d'√©tude article dans des revues Auteurs personnes Farcy, Emilie Auteur Burgeot, Thierry Auteur Haberkorn, Hansy Auteur Auffret, Michel Auteur Lagadic, Laurent Auteur Allenou Jean-Pierre Auteur Budzinski, H√©l√®ne Auteur Mazzella, Nicolas Auteur Pete, Romain Auteur Heydorff, Micheline Auteur et al. Date de publication 2013-02 Editeur(s) [S.l.] : HAL CCSD R√©sum√© Estuarine areas represent complex and highly changing environments at the interface between freshwater and marine aquatic ecosystems. Therefore, the aquatic organisms living in estuaries have to face highly variable environmental conditions. The aim of this work was to study the influence of environmental changes from either natural or anthropogenic origins on the physiological responses of Mytilus edulis. Mussels were collected in the Vilaine estuary during early summer because this season represents a critical period of active reproduction in mussels and of increased anthropogenic inputs from agricultural and boating activities into the estuary. The physiological status of the mussel M. edulis was evaluated through measurements of a suite of biomarkers related to: oxidative stress (catalase, malondialdehyde), detoxication (benzopyrene hydroxylase, carboxylesterase), neurotoxicity (acetylcholinesterase), reproductive cycle (vitelline, condition index, maturation stages), immunotoxicity (hemocyte concentration, granulocyte percentage, phagocytosis, reactive oxygen species production, oxidative burst), and general physiological stress (lysosomal stability). A selection of relevant organic contaminant (pesticides, (polycyclic aromatic hydrocarbons, polychlorobiphenyls) was measured as well as environmental parameters (water temperature, salinity, total suspended solids, turbidity, chlorophyll a, pheopigments) and mussel phycotoxin contamination. Two locations differently exposed to the plume of the Vilaine River were compared. Both temporal and inter-site variations of these biomarkers were studied. Our results show that reproduction cycle and environmental parameters such as temperature, organic ontaminants, and algal blooms could strongly influence the biomarker responses. These observations highlight the necessity to conduct integrated environmental approaches in order to better understand the causes of biomarker variations. Cat√©gories th√©matiques estuairemicrobiologie Mots-cl√©s libres Biomarkers/Confounding factors/Environmental fluctuations/Estuary/Mytilus edulis/Organic contaminants/Phycotoxins/Reproductive cycle/Temperature[SDE] Environmental Sciences Echelle de territoire r√©gion (ou supra) Note Environmental Science and Pollution Research
Environmental Science and Pollution Research, Springer Verlag (Germany), 2013, 20 (2), . <10.1007/s11356-012-1316-z>
Format pp.630-50 Document en ligne http://hal.univ-brest.fr/hal-00794181 Permalink http://etudes.bretagne-environnement.org/index.php?lvl=notice_display&id=147759External sources vs internal processes: What control inorganic As speciation and concentrations in the Penz√© estuary?
article dans des revues - 2011
Waeles, Matthieu, et al.
PermalinkInorganic arsenic speciation in the waters of the Penz√© estuary (NW France): Seasonal variations and fluxes to the coastal area
article scientifique - 2010
Vandenhecke, Jennifer, et al.
PermalinkEffect of nursery habitat degradation on flatfish population: Application to Solea solea in the Eastern Channel (Western Europe)
article scientifique - 2010
Mackinson, S., et al.
PermalinkPhosphorus dynamics and bioavailability in sediments of the Penze Estuary (NW France): in relation to annual P-fluxes and occurrences of Alexandrium Minutum
article scientifique - 2008-05
Andrieux-Loyer, Fran√ßoise, et al.
PermalinkCOMPOSITION DU PEUPLEMENT PISCICOLE D'UN PETIT ESTUAIRE ANTHROPIS√Č (LE COUESNON, FRANCE).
article scientifique - 2001
P. LAFFAILLE, et al.