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Auteur DRUON, J.-N.; FROMENTIN, J.-M.; AULANIER, F.; HEIKKONEN, J. url  openurl
  Titre Potential feeding and spawning habitats of Atlantic bluefin tuna in the Mediterranean Sea Type Article scientifique
  Année 2011 Publication Marine Ecology-progress Series Revue Abrégée  
  Volume 439 Numéro Pages 223-240  
  Mots-Clés Habitat mapping; Bluefin tuna; Thunnus thynnus; Feeding; Spawning; Mediterranean Sea; Remote sensing; Satellite data  
  Résumé Atlantic bluefin tuna Thunnus thynnus (ABFT) is a fish of high market value which has recently become strongly overexploited, notably in the Mediterranean Sea. This area is an essential habitat for ABFT reproduction and growth. We present here an approach for deriving the daily mapping of potential ABFT feeding and spawning habitats based on satellite-derived sea surface temperature (SST) and chl a concentration. The feeding habitat was mainly derived from the simultaneous occurrence of oceanic fronts of temperature and chl a content while the spawning habitat was mostly inferred from the heating of surface waters. Generally, higher chl a contents were found to be preferred for the feeding habitat and a minimum SST value was found for the spawning habitat. Both habitats were defined by the presence of relevant oceanographic features and are therefore potential and functionally-linked habitats. This approach provides, for the first time, a synoptic view of the potential ABFT habitats in the Mediterranean Sea. The model performs well in areas where both satellite data and ABFT observations are available, as 80% of presence data are in the vicinity of potential habitats. The computed monthly, seasonal and annual maps of potential feeding and spawning habitat of ABFT from 2003 to 2009 are in good agreement with current knowledge on ABFT. Overall, the habitat size of ABFT is about 6% of the Mediterranean Sea surface. The results displayed a strong seasonality in habitat size and locations as well as high year-to-year variations (30 to 60%), particularly for the potential spawning habitat, which is key information for evaluating the utility of ABFT Marine Protected Areas in the Mediterranean Sea.  
  Adresse IFREMER, Ctr Rech Halieut Mediterraneen & Trop, F-34203 Sete, France.  
  Auteur institutionnel Thèse  
  Editeur Inter-research 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 0171-8630 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 16053 collection 1003  
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Auteur Zilius, M.; Bartoli, M.; Bresciani, M.; Katarzyte, M.; Ruginis, T.; Petkuviene, J.; Lubiene, I.; Giardino, C.; Bukaveckas, P.A.; De Wit, R.; Razinkovas-Baziukas, A. url  doi
openurl 
  Titre Feedback Mechanisms Between Cyanobacterial Blooms, Transient Hypoxia, and Benthic Phosphorus Regeneration in Shallow Coastal Environments Type Article scientifique
  Année 2014 Publication Revue Abrégée Estuaries and Coasts  
  Volume 37 Numéro 3 Pages 680-694  
  Mots-Clés baltic sea; chesapeake bay; curonian lagoon; Cyanobacterial blooms; ecosystem metabolism; Estuary; gulf; Hypoxia; Net; nutrient limitation; Oxygen; Phosphorus release; respiration; satellite data; temporal variability  
  Résumé We investigated the dissolved oxygen metabolism of the Curonian Lagoon (Baltic Sea) to assess the relative contributions of pelagic and benthic processes to the development of transient hypoxic conditions in shallow water habitats. Metabolism measurements along with the remote sensing-derived estimates of spatial variability in chlorophyll a were used to evaluate the risk of hypoxia at the whole lagoon level. Our data demonstrate that cyanobacterial blooms strongly inhibit light penetration, resulting in net heterotrophic conditions in which pelagic oxygen demand exceeds benthic oxygen demand by an order of magnitude. The combination of bloom conditions and reduced vertical mixing during calm periods resulted in oxygen depletion of bottom waters and greater sediment nutrient release. The peak of reactive P regeneration (nearly 30 mu mol m(-2) h(-1)) coincided with oxygen depletion in the water column, and resulted in a marked drop of the inorganic N:P ratio (from > 40 to < 5, as molar). Our results suggest a strong link between cyanobacterial blooms, pelagic respiration, hypoxia, and P regeneration, which acts as a feedback in sustaining algal blooms through internal nutrient cycling. Meteorological data and satellite-derived maps of chlorophyll a were used to show that nearly 70 % of the lagoon surface (approximately 1,000 km(2)) is prone to transient hypoxia development when blooms coincide with low wind speed conditions.  
  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 1559-2723 ISBN Médium  
  Région Expédition Conférence  
  Notes <p>ISI Document Delivery No.: AF0SM<br/>Times Cited: 1<br/>Cited Reference Count: 66<br/>Zilius, Mindaugas Bartoli, Marco Bresciani, Mariano Katarzyte, Marija Ruginis, Tomas Petkuviene, Jolita Lubiene, Irma Giardino, Claudia Bukaveckas, Paul A. de Wit, Rutger Razinkovas-Baziukas, Arturas<br/>European Union Structural Funds project “Postdoctoral Fellowship Implementation in Lithuania”; Fulbright Fellowship; ESA project [AO-553]; CYAN-IS-WAS (Ministero dell'Istruzione dell'Universita e della Ricerca, Science and technological of Sweden); CLAM-PHYM (Italian Space Agency) [ASI I/015/11/0]<br/>Mindaugas Zilius was supported by a postdoctoral fellowship funded by the European Union Structural Funds project “Postdoctoral Fellowship Implementation in Lithuania.” Paul Bukaveckas was supported by a Fulbright Fellowship during his residence at Klaipeda University. MERIS data were made available through the ESA project AO-553 (MELINOS). This study was co-funded by CYAN-IS-WAS (Ministero dell'Istruzione dell'Universita e della Ricerca, Science and technological cooperation between Italy and the Kingdom of Sweden) and CLAM-PHYM (Italian Space Agency, contract ASI I/015/11/0) projects. We gratefully thank the Lithuanian Hydrometeorological Service of the Ministry of Environment for providing meteorological data. We also gratefully thank three anonymous reviewers for valuable comments which improved the quality of the manuscript.<br/>Springer<br/>New york</p> Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1184  
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