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Auteur Ramirez-Romero, E.; Molinero, J.C.; Sommer, U.; Salhi, N.; Yahia, O.K.-D.; Yahia, M.N.D.
Titre Phytoplankton size changes and diversity loss in the southwestern Mediterranean Sea in relation to long-term hydrographic variability Type Article scientifique
Année 2020 Publication Revue Abrégée Estuar. Coast. Shelf Sci.
Volume 235 Numéro Pages (down) 106574
Mots-Clés bay; climate-change; Diversity loss; dynamics; evolution; jellyfish; marine; Nanophytoplankton; Ocean warming; patterns; Phytoplankton diversity; plankton communities; Size structural changes; Southwestern mediterranean; temperature; time-series
Résumé Structural changes in plankton primary producers have large implications for food web dynamics, energy fluxes and the vertical export of biogenic particulate carbon. Here we examine phytoplankton data spanning the period 1993-2008 from the Bay of Tunis, southwestern Mediterranean Sea, in relation to long term hydroclimate variability. We show a conspicuous shift in the structure of the phytoplankton community characterized by an increase of small-sized species and diversity loss, revealing a dominance of smaller blooming diatoms and cyanobacteria. Such changes were concurrent with marked modifications in hydroclimatic patterns experienced in the Bay of Tunis consisting of a shift towards enhanced winter precipitation together with rising temperatures. This novel study shows an overall rise in the proportion of small phytoplankton cells and a decreasing trend in phytoplankton diversity in the southern Mediterranean area. These findings warn of a potential decline of trophic efficiency and lesser food web stability resulting from mean size reduction and the diversity loss.
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ISSN 0272-7714 ISBN Médium
Région Expédition Conférence
Notes WOS:000527915700034 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2766
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Auteur Marsac, F.; Galletti, F.; Ternon, J.-F.; Romanov, E.V.; Demarcq, H.; Corbari, L.; Bouchet, P.; Roest, W.R.; Jorry, S.J.; Olu, K.; Loncke, L.; Roberts, M.J.; Ménard, F.
Titre Seamounts, plateaus and governance issues in the southwestern Indian Ocean, with emphasis on fisheries management and marine conservation, using the Walters Shoal as a case study for implementing a protection framework Type Article scientifique
Année 2019 Publication Revue Abrégée Deep Sea Research Part II: Topical Studies in Oceanography
Volume Numéro Pages (down) 104715
Mots-Clés Amended Nairobi Convention; Areas Beyond National Jurisdiction; Benthic biodiversity; Deep-sea fisheries; Deep-sea mining; International Law of the Sea; Marine protected areas; Saya de Malha Bank; South Indian Ocean Fisheries Agreement; Vulnerable Marine Ecosystems
Résumé There is a growing interest in the management of seamounts of the Southwestern Indian Ocean (SWIO) both in waters under national jurisdictions and in the Areas Beyond National Jurisdiction (ABNJ). New scientific knowledge has been gathered through various oceanographic cruises during the past decade, and new agreements are under consideration globally to promote conservation and sustainable use of the biodiversity in the ABNJ, where the deep sea ecosystems associated with seamounts are a growing matter of concern. SWIO seamounts have attracted the interests of fishers since the 1960s, and contracts for mining exploration have been granted recently. Seamounts are known to shelter rich, fragile and poorly resilient ecosystems whose important ecological functions are threatened by various anthropogenic pressures. Whereas many seamounts and shoals are located in national waters, many others fall in the ABNJ, with no current legal status per se. To ensure conservation of their habitats and biodiversity, it is essential that protection measures are instigated under an internationally recognized legal and institutional framework. In this paper, we review the current state of such a framework relevant to seamounts, with emphasis on fisheries and conservation in the SWIO. An emblematic seamount, the Walters Shoal, is selected as a case study to discuss how it could become a fully-protected space in the ABNJ. As a large part of the SWIO is under the mandate of the Nairobi Convention (as a Regional Sea under the auspices of UNEP), guidelines are proposed to encourage dedicated seamount governance within the framework of this Convention.
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Volume de collection Numéro de collection Edition
ISSN 0967-0645 ISBN Médium
Région Expédition Conférence
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2689
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Auteur Kermagoret, C.; Claudet, J.; Derolez, V.; Nugues, M.M.; Ouisse, V.; Quillien, N.; Bailly, D.
Titre Dataset on marine ecosystem services supplied by coral reefs, sandy beaches and coastal lagoons in different eutrophication states Type Article scientifique
Année 2019 Publication Revue Abrégée Data Brief
Volume 25 Numéro Pages (down) 104078
Mots-Clés dinoflagellate; Ecosystem services; Eutrophication; Marine biodiversity; Marine ecosystems; patterns
Résumé This data article provides indicators of Ecosystem Service (ES) supply for coral reefs, sandy beaches and coastal lagoons in different ecological states regarding eutrophication. 14 ES are considered: food through fisheries; material; molecules; coastal protection; nutrient regulation; pathogen regulation; climate regulation; support of recreational and leisure activities; contribution to a pleasant landscape; contribution to culture and territorial identity; emblematic biodiversity; habitat; trophic networks; recruitment. For each ecosystem 3 to 4 eutrophication states are described. Indicators of ES supply are filled on the basis of a literature review supplemented with expert-knowledge. A semi-quantification of the indicator value is finally provided. Tendencies and trade-offs between ES are analyzed in How does eutrophication impact bundles of ecosystem services in multiple coastal habitats using state-and-transition models [1]. (c) 2019 The Authors. Published by Elsevier Inc.
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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 2352-3409 ISBN Médium
Région Expédition Conférence
Notes WOS:000495104500105 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2680
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Auteur Leblad, B.R.; Amnhir, R.; Reqia, S.; Sitel, F.; Daoudi, M.; Marhraoui, M.; Abdellah, M.K.O.; Veron, B.; Er-Raioui, H.; Laabir, M.
Titre Seasonal variations of phytoplankton assemblages in relation to environmental factors in Mediterranean coastal waters of Morocco, a focus on HABs species Type Article scientifique
Année 2020 Publication Revue Abrégée Harmful Algae
Volume 96 Numéro Pages (down) 101819
Mots-Clés bay; bizerte lagoon; climate-change; domoic acid; Environmental factors; gymnodinium-catenatum; HABs; harmful algal blooms; Phytoplankton diversity; pseudo-nitzschia; psp toxins; shellfish; SW Mediterranean; temperature; Toxins
Résumé Studies on phytoplankton and in particular Harmful Algal Blooms (HABs) species in southern Mediterranean waters are scarce. We performed from April 2008 to June 2009 weekly investigations on microphytoplankton community structure and abundance in two contrasted marine ecosystems located in the western Moroccan Mediterranean coast, M'diq Bay and Oued Laou Estuary. Simultaneously, we measured the main physico-chemical parameters. Globally, the two studied areas showed comparable values of the assessed abiotic environmental factors. Temperature and salinity followed seasonal variation with values ranging from 13.5 degrees C to 21.4 degrees C and 31 to 36.8, respectively. Average nutrient values in surface water ranged from 0.7 to 45.76 mu M for dissolved inorganic nitrogen, 0.02-2.10 mu M for PO4 and 0.23-17.46 mu M for SiO4 in the study areas. A total of 92 taxa belonging to 8 taxonomic classes were found. The highest number of microphytoplankton abundance reached 1.2 x 10(6) cells L-1 with diatoms being the most abundant taxa. Factorial Discriminant Analysis (FDA) and Spearman correlation test showed a significant seasonal discrimination of dominant microphytoplankton species. These micro-organisms were associated with different environmental variables, in particular temperature and salinity. Numerous HABs species were encountered regularly along the year. Although Dinophysis species and Prorocentrum lima were present in both sites, no Lipophilic Shellfish Poisoning was detected for the analyzed bivalve mollusks. Domoic acid (DA), produced by toxic species of Pseudo-nitzschia was found with concentrations up to 18 mu g DA g(-1) in the smooth clam Callista chione. Data showed that the observed persistent and dramatic Paralytic Shellfish Poisoning (PSP) intoxication of mollusks resulted probably of Gymnodinium catenatum proliferations in both studied areas. Contrary to C. chione, the cockle Achanthocardia tuberculatum showed a permanent and extremely high toxicity level during the 15 months survey with up to 7545 mu g Equivalent Saxitoxin kg(-1) flesh (ten times higher than the sanitary threshold of 800 tg eqSTX Kg(-1) flesh). The present work highlights for the first time the dynamic of microphytoplankton including HABs species and their associated toxin accumulation in the commercially exploited shellfish in the southern western Mediterranean waters of Morocco. Furthermore, the acquired data will help us to improve the monitoring of HABs species and related toxins in these coastal marine systems.
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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
Région Expédition Conférence
Notes WOS:000541912700003 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2820
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Auteur de Melo, C.C.; Cavalcanti Soares, A.P.; Pelage, L.; Eduardo, L.N.; Fredou, T.; Lira, A.S.; Ferreira, B.P.; Bertrand, A.; Lucena-Fredou, F.
Titre Haemulidae distribution patterns along the Northeastern Brazilian continental shelf and size at first maturity of the most abundant species Type Article scientifique
Année 2020 Publication Revue Abrégée Reg. Stud. Mar. Sci.
Volume 35 Numéro Pages (down) 101226
Mots-Clés archipelago; ceara state; coral-reef fish; diversity; grunts haemulidae; habitat; maturation; pernambuco; plumieri teleostei haemulidae; seagrass
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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 2352-4855 ISBN Médium
Région Expédition Conférence
Notes WOS:000525758600056 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2769
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