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| Registros recuperados: 10 | |
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| Qui-minet, Zujaila Nohemy; Coudret, Jérôme; Davoult, Dominique; Grall, Jacques; Mendez‐sandin, Miguel; Cariou, Thierry; Martin, Sophie. |
| Made up of calcareous coralline algae, maerl beds play a major role as ecosystem engineers in coastal areas throughout the world. They undergo strong anthropogenic pressures, which may threaten their survival. The aim of this study was to gain insight into the future of maerl beds in the context of global and local changes. We examined the effects of rising temperatures (+3°C) and ocean acidification (−0.3 pH units) according to temperature and pH projections (i.e., the RCP 8.5 scenario), and nutrient (N and P) availability on three temperate maerl species (Lithothamnion corallioides, Phymatolithon calcareum, and Lithophyllum incrustans) in the laboratory in winter and summer conditions. Physiological rates of primary production, respiration, and... |
| Tipo: Text |
Palavras-chave: Calcification; Maerl; Nitrate; Ocean acidification; Ocean warming; Phosphate; Photosynthesis; Respiration. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00595/70722/68955.pdf |
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| Borelli, G; Guibbohni, M; Mayer Gostan, N; Priouzeau, France; De Pontual, Helene; Allemand, D; Puverel, S; Tambutte, E; Payan, P. |
| Ionic and organic parameters of the otolith calcification process in the trout Oncorhynchus mykiss were analysed in plasma and endolymph over the day:night cycle. Plasma pH remained constant and total CO2 concentration was significantly lower (by 21%) during the day than at night. Calcifying parameters (total CO2, total calcium concentration) were measured in the proximal and distal endolymphs and were unchanged in the latter during the day:night cycle, but fluctuated in the former. Non-collagenous protein and collagen concentrations in endolymph were higher (1.5- and 10-fold, respectively) during the day than at night. As there was no change in total calcium concentration, we propose that Ca2+ increases during the dark period and was maximal by the end of... |
| Tipo: Text |
Palavras-chave: Endolymph; Day night cycle; Calcification; Otolith. |
| Ano: 2003 |
URL: https://archimer.ifremer.fr/doc/2003/publication-418.pdf |
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| Freeman, Natalie M.; Lovenduski, Nicole S.. |
| Widespread ocean acidification is occurring as the ocean absorbs anthropogenic carbon dioxide from the atmosphere, threatening marine ecosystems, particularly the calcifying plankton that provide the base of the marine food chain and play a key role within the global carbon cycle. We use satellite estimates of particulate inorganic carbon (PIC), surface chlorophyll, and sea surface temperature to provide a first estimate of changing calcification rates throughout the Southern Ocean. From 1998 to 2014 we observe a 4% basin-wide reduction in summer calcification, with approximate to 9% reductions in large regions (approximate to 1 x 10(6) km(2)) of the Pacific and Indian sectors. Southern Ocean trends are spatially heterogeneous and primarily driven by... |
| Tipo: Text |
Palavras-chave: Southern Ocean; Calcification; Particulate inorganic carbon; Carbonate ion; Antarctic polar front. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00292/40371/38941.pdf |
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| Alzieu, Claude; Heral, Maurice; Thibaud, Yves; Dardignac, Marie-jose; Feuillet, Michèle. |
| Experiments in oyster-breeding areas where oyster Crassostrea gigas suffers from anomalies of calcification, show an obvious correlation between the importance of the malformation of shells and the vicinity of port areas where a great number of boats usually stay. Organotin compounds contained in antifouling paints, and more precisely Tributyltin fluoride (TBTF) induce, in experimental environment, similar anomalies to those observed in natural environment. The amounts of total tin in the tissues of oysters living in the vicinity of spots where organotin products are brought in, can reach high values, though they appear to decrease rapidly whereas the environmental contamination lessens. The authors suggest that results of organotin upon the mechanisms of... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Pollution effects; Toxicity; Calcification; Fouling control; Paints. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-1898.pdf |
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| Larvor, Helene. |
| L'étude du brunissement pathologique des valves de la coquille Saint-Jacques a permis d'identifier différents types d'altérations des mécanismes de la calcification : des détériorations microstructurales concomitantes avec une pigmentation brune anormale de la couche interne des tests. Les mécanismes de biominéralisation contrôlant l'intégration du carbonate de calcium dans les structures coquillières ne sont pas altérés : le taux de calcium, la minéralogie et la composition en acides aminés des matrices organiques cristallines sont équivalents dans les valves brunes et les valves blanches. Par contre, la présence d'une eumélanine, responsable de la coloration brune, est détectée dans les matrices organiques insolubles des régions coquillières aux... |
| Tipo: Text |
Palavras-chave: Calcification; Coquille; Mélanine; Microstructure; Pecten maximus; Mollusques; Perturbations environnementales; Biominéralisation. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00043/15449/12823.pdf |
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| Pecquerie, Laure; Fablet, Ronan; De Pontual, Helene; Bonhommeau, Sylvain; Alunno-bruscia, Marianne; Petitgas, Pierre; Kooijman, Sebastiaan A. L. M.. |
| Environmental conditions experienced by aquatic organisms are archived in biogenic carbonates such as fish otoliths, bivalve shells and coral skeletons. These calcified structures present an accretionary growth and variations in optical properties - color or opacity - that are used to reconstruct time. Full and reliable exploitation of the information extracted from these structures is, however, often limited as the metabolic processes that control their growth and their optical properties are poorly understood. Here, we propose a new modeling framework that couples both the growth of a biogenic carbonate and its optical properties with the metabolism of the organism. The model relies on well-tested properties of Dynamic Energy Budget (DEB) theory. It is... |
| Tipo: Text |
Palavras-chave: Otolith; Calcification; Metabolism; Bioenergetic model; Food reconstruction; Dynamic Energy Budget theory. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00060/17082/14593.pdf |
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| Registros recuperados: 10 | |
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