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Auteur (up) Grzebyk, D.; Audic, S.; Lasserre, B.; Abadie, E.; de Vargas, C.; Bec, B.
Titre Insights into the harmful algal flora in northwestern Mediterranean coastal lagoons revealed by pyrosequencing metabarcodes of the 28S rRNA gene Type Article scientifique
Année 2017 Publication Revue Abrégée Harmful Algae
Volume 68 Numéro Pages 1-16
Mots-Clés Phytoplankton diversity; Harmful algae; Monitoring; alexandrium dinophyceae; dinoflagellate stoeckeria-changwonensis; domoic acid accumulation; eastern adriatic sea; Metabarcoding; partial lsu rdna; pfiesteria-piscicida dinophyceae; phylogenetic-relationships; pseudo-nitzschia bacillariophyceae; species complex dinophyceae; toxic dinoflagellate
Résumé This study investigated the genetic diversity of phytoplankton communities in six shallow lagoons located on the French coast of the northwestern Mediterranean Sea that represented a trophic gradient ranging from oligotrophic to hypereutrophic. The phytoplankton communities were sampled once a month from spring (May) to the beginning of autumn (September/early October) in 2012 and fractionated by size. Metabarcodes were generated from cDNAs by targeting the D1-D2 region of the 28S rRNA gene and pyrosequenced using Roche 454 technology. Examination of the annotated barcodes revealed harmful algal species not previously documented in these lagoons. Three ichthyotoxic species belonging to Pfiesteriaceae were detected: Luciella masanensis was relatively widespread and abundant in many samples, whereas Pfiesteria piscicida and Stoeckeria changwonensis were found as single barcode sequences. Furthermore, a phylogenetic analysis of barcodes annotated as belonging to Pfiesteriaceae suggested the existence of two previously undescribed clades. The other toxic or potentially harmful dinoflagellates detected through rare barcodes were Dinophysis acuminata, Vulcanodinium rugosum, Alexandrium andersonii and A. ostenfeldii. The two most abundant dinoflagellate taxa were Gymnodinium litoralis and Akashiwo sanguinea with respect to sequence numbers. Four diatom species from the genus Pseudo-nitzschia that potentially produce domoic acid were identified (P. galaxiae, P. delicatissima, P. brasiliana and P. calliantha). These observations are discussed in terms of the literature and monitoring records related to the identified taxa in this Mediterranean area. (C) 2017 Elsevier B.V. All rights reserved.
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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 1568-9883 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2227
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Auteur (up) Gueroun, S.K.M.; Molinero, J.C.; Piraino, S.; Daly Yahia, M.N.
Titre Population dynamics and predatory impact of the alien jellyfish Aurelia solida (Cnidaria, Scyphozoa) in the Bizerte Lagoon (southwestern Mediterranean Sea) Type Article scientifique
Année 2020 Publication Revue Abrégée Mediterr. Mar. Sci.
Volume 21 Numéro 1 Pages 22-35
Mots-Clés abundance; asexual reproduction rates; aurita cnidaria; common jellyfish; cyanea-capillata; gullmar fjord; mesozooplankton; moon jellyfish; predation; prey selection; prince-william-sound; Scyphomedusae; SW Mediterranean; tokyo bay; zooplankton
Résumé Understanding the life cycle strategies and predatory impact of alien jellyfish species is critical to mitigate the impact that these organisms may have on local populations, biodiversity, and ultimately on the functioning of food webs. In the Mediterranean Sea, little is known about the dynamics of alien jellyfish, despite this biodiversity hotspot being one of the most threatened areas by increasing numbers of alien jellyfish. Here, we investigated the population dynamics and predatory impact of a non-indigenous scyphomedusa, Aurelia solida Browne 1905, in the Bizerte Lagoon, Tunisia. The study was based on bimonthly surveys performed over two consecutive years, from November 2012 to August 2014. Field observations showed that the planktonic phase of A. solida occurs from winter to early summer. Prey composition was investigated by means of gut content and field zooplankton analyses. Calanoid copepods, mollusc larvae, and larvaceans represented the main food items of A. solida. To determine the jellyfish feeding rate and their predatory impact on zooplankton populations, the digestion time for zooplankton prey was assessed at three different temperatures: 13, 18, and 23 degrees C in laboratory conditions, corresponding to the average range of temperatures encountered by A. solida in the Bizerte Lagoon. We found that A. solida consumed 0.5-22.5% and 0.02-37.3% of the daily zooplankton standing stock in 2013 and 2014, respectively. These results indicate a non-negligible but restricted seasonal grazing impact on some mesozooplankton groups, explained by the relatively short lifespan of the medusa stage (5-6 months).
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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 1108-393x ISBN Médium
Région Expédition Conférence
Notes WOS:000524248700003 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2773
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Auteur (up) Hadjadji, I.; Masseret, E.; Plisson, B.; Laabir, M.; Cecchi, P.; Collos, Y.
Titre Clonal variation in physiological parameters of Alexandrium tamarense: implications for biological invasions and maintenance Type Article scientifique
Année 2012 Publication Revue Abrégée Cah. Biol. Mar.
Volume 53 Numéro 3 Pages 357-363
Mots-Clés Alexandrium tamarense; Fitness; Growth rate; Humic acid; Intraspecific variability; Lag phase; blooms; catenella; complex dinophyceae; dinoflagellate; dinophyceae; growth; humic substances; marine-phytoplankton; southern france; thau lagoon; urea uptake
Résumé The study of the intraspecific variability is a crucial step for understanding the successful establishment and maintenance of invasive species. Alexandrium tamarense strains isolated in spring 2007 from a single bloom in Thau lagoon have been grown on three different media (ESNW based on natural seawater, and the artificial media, ESAW, ESAW+HA). A large diversity in the ability of strains to grow on these media was found. Irrespective of medium composition, growth curves followed three models: (1) a classical shape, (2) a population crash followed in some cases (3) by growth recovery. Some strains were able to show significant growth in an environment completely artificial (ESAW). ANOVA indicated a significant difference between groups in growth rates allowing the distinction of contrasted categories among the strains studied in ESNW medium. These statistical tests also indicated the presence of distinct groups among the strains grown in the ESAW as well as for those on ESAW+HA medium. Lag phases were extremely variable between strains in all environments, suggesting a high variability of adaptation to the environment. The results revealed that wide fitness variations were exhibited by diverse conspecific A. tamarense individuals co-existing during a bloom.
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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 0007-9723 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 473
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Auteur (up) Hoang, H.T.T.; Duong, T.T.; Nguyen, K.T.; Le, Q.T.P.; Luu, M.T.N.; Trinh, D.A.; Le, A.H.; Ho, C.T.; Dang, K.D.; Némery, J.; Orange, D.; Klein, J.
Titre Impact of anthropogenic activities on water quality and plankton communities in the Day River (Red River Delta, Vietnam) Type Article scientifique
Année 2018 Publication Revue Abrégée Environ Monit Assess
Volume 190 Numéro 2 Pages 67
Mots-Clés Water quality; Tropical; Vietnam; Day River; Plankton communities; Red River Delta
Résumé Planktons are a major component of food web structure in aquatic ecosystems. Their distribution and community structure are driven by the combination and interactions between physical, chemical, and biological factors within the environment. In the present study, water quality and the community structure of phytoplankton and zooplankton were monthly investigated from January to December 2015 at 11 sampling sites along the gradient course of the Day River (Red River Delta, northern Vietnam). The study demonstrated that the Day River was eutrophic with the average values of total phosphorus concentration 0.17 mg/L, total nitrogen concentration 1.98 mg/L, and Chl a 54 μg/L. Microscopic plankton analysis showed that phytoplankton comprised 87 species belonging to seven groups in which Chlorophyceae, Bacillariophyceae, and Cyanobacteria accounted for the most important constituents of the river's phytoplankton assemblage. A total 53 zooplankton species belonging to three main groups including Copepoda, Cladocera, and Rotatoria were identified. Plankton biomass values were greatest in rainy season (3002.10-3 cell/L for phytoplankton and 12.573 individuals/m3 for zooplankton). Using principal correspondence and Pearson correlation analyses, it was found that the Day River was divided into three main site groups based on water quality and characteristics of plankton community. Temperature and nutrients (total phosphorus and total nitrogen) are key factors regulating plankton abundance and distribution in the Day River.
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Editeur Lieu de Publication Éditeur
Langue eng Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1573-2959 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2263
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Auteur (up) Jaspers, C.; Huwer, B.; Antajan, E.; Hosia, A.; Hinrichsen, H.-H.; Biastoch, A.; Angel, D.; Asmus, R.; Augustin, C.; Bagheri, S.; Beggs, S.E.; Balsby, T.J.S.; Boersma, M.; Bonnet, D.; Christensen, J.T.; Daenhardt, A.; Delpy, F.; Falkenhaug, T.; Finenko, G.; Fleming, N.E.C.; Fuentes, V.; Galil, B.; Gittenberger, A.; Griffin, D.C.; Haslob, H.; Javidpour, J.; Kamburska, L.; Kube, S.; Langenberg, V.T.; Lehtiniemi, M.; Lombard, F.; Malzahn, A.; Marambio, M.; Mihneva, V.; Moller, L.F.; Niermann, U.; Okyar, M.I.; Ozdemir, Z.B.; Pitois, S.; Reusch, T.B.H.; Robbens, J.; Stefanova, K.; Thibault, D.; van der Veer, H.W.; Vansteenbrugge, L.; van Walraven, L.; Wozniczka, A.
Titre Ocean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia Type Article scientifique
Année 2018 Publication Revue Abrégée Glob. Ecol. Biogeogr.
Volume 27 Numéro 7 Pages 814-827
Mots-Clés abundance; biodiversity; biological invasions; black-sea; caspian sea; consequences; ctenophore mnemiopsis-leidyi; gelatinous zooplankton; invasion corridors; invasive species; jellyfish; larval transport; marine connectivity; Mnemiopsis leidyi; north-sea; range expansion; source populations; source-sink dynamics; waters; zooplankton
Résumé Aim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further distribution after the initial establishment of non-native species remain largely unresolved, especially in marine systems. Ocean currents can be a major driver governing range occupancy, but this has not been accounted for in most invasion ecology studies so far. We investigate how well initial establishment areas are interconnected to later occupancy regions to test for the potential role of ocean currents driving secondary spread dynamics in order to infer invasion corridors and the source-sink dynamics of a non-native holoplanktonic biological probe species on a continental scale. Location: Western Eurasia. Time period: 1980s-2016. Major taxa studied: 'Comb jelly' Mnemiopsis leidyi. Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents. Additionally, genetic markers are used to test the predicted connectivity between subpopulations. Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions and the timing of first occurrence of our holoplanktonic non-native biological probe species, leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over large distances after local extinctions. Main conclusions: Although the release of ballast water from container ships may contribute to the dispersal of non-native species, our results highlight the importance of ocean currents driving secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for secondary spread dynamics on a continental scale. Invasion risk assessments should consider large-scale connectivity patterns and the potential source regions of non-native marine species.
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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 1466-822x ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 2390
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