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Pollutant content in marine debris and characterization by thermal decomposition Texte intégral
2017
Iñiguez, M.E. | Conesa, J.A. | Fullana, A.
Pollutant content in marine debris and characterization by thermal decomposition Texte intégral
2017
Iñiguez, M.E. | Conesa, J.A. | Fullana, A.
Marine debris (MDs) produces a wide variety of negative environmental, economic, safety, health and cultural impacts. Most marine litter has a very low decomposition rate (plastics), leading to a gradual accumulation in the coastal and marine environment. Characterization of the MDs has been done in terms of their pollutant content: PAHs, ClBzs, ClPhs, BrPhs, PCDD/Fs and PCBs. The results show that MDs is not a very contaminated waste. Also, thermal decomposition of MDs materials has been studied in a thermobalance at different atmospheres and heating rates. Below 400–500K, the atmosphere does not affect the thermal degradation of the mentioned waste. However, at temperatures between 500 and 800K the presence of oxygen accelerates the decomposition. Also, a kinetic model is proposed for the combustion of the MDs, and the decomposition is compared with that of their main constituents, i.e., polyethylene (PE), polystyrene (PS), polypropylene (PP), nylon and polyethylene-terephthalate (PET).
Afficher plus [+] Moins [-]Pollutant content in marine debris and characterization by thermal decomposition Texte intégral
2017
Iñiguez, María Esperanza | Conesa, Juan A. | Fullana, Andres | Conesa, Juan A. | Fullana, Andres | Universidad de Alicante. Departamento de Ingeniería Química | Residuos, Energía, Medio Ambiente y Nanotecnología (REMAN)
Marine debris (MDs) produces a wide variety of negative environmental, economic, safety, health and cultural impacts. Most marine litter has a very low decomposition rate (plastics), leading to a gradual accumulation in the coastal and marine environment. Characterization of the MDs has been done in terms of their pollutant content: PAHs, ClBzs, ClPhs, BrPhs, PCDD/Fs and PCBs. The results show that MDs is not a very contaminated waste. Also, thermal decomposition of MDs materials has been studied in a thermobalance at different atmospheres and heating rates. Below 400–500 K, the atmosphere does not affect the thermal degradation of the mentioned waste. However, at temperatures between 500 and 800 K the presence of oxygen accelerates the decomposition. Also, a kinetic model is proposed for the combustion of the MDs, and the decomposition is compared with that of their main constituents, i.e., polyethylene (PE), polystyrene (PS), polypropylene (PP), nylon and polyethylene-terephthalate (PET). | Support for this work was provided by the CTQ2016-76608-R project from the Ministry of Economy and Competitiveness (Spain) and the PROMETEOII/2014/007 project from the Valencian Community Government (Spain). The author also thanks the Ministry of Economy, Industry and Competitiveness (Spain) for a Ph.D. grant (BES-2014-069473).
Afficher plus [+] Moins [-]Habitat selection by marine larvae in changing chemical environments Texte intégral
2017
Lecchini, D. | Dixson, D.L. | Lecellier, G. | Roux, N. | Frédérich, B. | Besson, M. | Tanaka, Y. | Banaigs, B. | Nakamura, Y.
Habitat selection by marine larvae in changing chemical environments Texte intégral
2017
Lecchini, D. | Dixson, D.L. | Lecellier, G. | Roux, N. | Frédérich, B. | Besson, M. | Tanaka, Y. | Banaigs, B. | Nakamura, Y.
The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.
Afficher plus [+] Moins [-]Habitat selection by marine larvae in changing chemical environments Texte intégral
2017
Lecchini, David | Dixson, Danielle L. | Lecellier, Gael | Roux, Natacha | Frederich, Bruno | Besson, Marc | Tanaka, Y. | Banaigs, Bernard | Nakamura, Yohei | AFFISH-RC - Applied and Fundamental FISH Research Center - ULiège
peer reviewed | The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.
Afficher plus [+] Moins [-]Habitat selection by marine larvae in changing chemical environments Texte intégral
2017
Lecchini, D. | Dixson, D.L. | Lecellier, G. | Roux, N. | Frédérich, B. | Besson, M. | Tanaka, Y. | Banaigs, B. | Nakamura, Y. | Centre de recherches insulaires et observatoire de l'environnement (CRIOBE) ; Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Excellence CORAIL (LabEX CORAIL) ; Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA) | School of Marine Science and Policy ; University of Delaware [Newark] | Biologie intégrative des organismes marins (BIOM) ; Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB) ; Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Morphologie Fonctionnelle et Evolutive ; Université de Liège = University of Liège = Universiteit van Luik = Universität Lüttich (ULiège) | Institut de Génomique Fonctionnelle de Lyon (IGFL) ; École normale supérieure de Lyon (ENS de Lyon) ; Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | sesoko station ; University of the Ryukyus [Okinawa] | Graduate School of Kuroshio Science ; Kochi University | ANR-10-LABX-0008,CORAIL,Coral reefs facing global change(2010)
International audience | The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.
Afficher plus [+] Moins [-]Response of the pearl oyster Pinctada margaritifera to cadmium and chromium: Identification of molecular biomarkers Texte intégral
2017
Gueguen, Yannick | Denis, Saulnier | Adrien, Santini | Kevin, Magre | Pierre, Garen | Solène, Bernagout | Marine, Nohl | Patrick, Bouisset | Herehia, Helme | Serge, Planes | Gilles, Le Moullac
Response of the pearl oyster Pinctada margaritifera to cadmium and chromium: Identification of molecular biomarkers Texte intégral
2017
Gueguen, Yannick | Denis, Saulnier | Adrien, Santini | Kevin, Magre | Pierre, Garen | Solène, Bernagout | Marine, Nohl | Patrick, Bouisset | Herehia, Helme | Serge, Planes | Gilles, Le Moullac
This study was designed to identify in the pearl oyster Pinctada margaritifera, used as a bio-accumulator, molecular biomarkers for the presence of heavy metals in the lagoon environment. Pearl oysters were exposed to 2 concentrations (1 and 10μgL−1) of cadmium (Cd) and chromium (Cr) compared to a control. Twelve target genes encoding proteins potentially involved in the response to heavy metal contamination with antioxidant, detoxification or apoptosis activities were selected. P. margaritifera accumulated Cd but not Cr, and mortality was related to the amount of Cd accumulated in tissues. In response to Cd-Cr contamination, metallothionein (MT) was significantly up-regulated by Cd-Cr at both concentrations, while 7 others (SOD, CAT, GPX, GSTO, GSTM, CASP, MDR) were down-regulated. Based on the development of these molecular tools, we propose that the pearl oyster, P. margaritifera, could be used as a sentinel species for heavy metal contamination in the lagoons of tropical ecosystems.
Afficher plus [+] Moins [-]Response of the pearl oyster Pinctada margaritifera to cadmium and chromium: Identification of molecular biomarkers Texte intégral
2017
Gueguen, Yannick | Saulnier, Denis | Santini, Adrien | Magre, Kevin | Garen, Pierre | Bernagout, Solene | Nohl, Marine | Bouisset, Patrick | Helme, Herehia | Planes, Serge | Le Moullac, Gilles
This study was designed to identify in the pearl oyster Pinctada margaritifera, used as a bio-accumulator, molecular biomarkers for the presence of heavy metals in the lagoon environment. Pearl oysters were exposed to 2 concentrations (1 and 10 μg L− 1) of cadmium (Cd) and chromium (Cr) compared to a control. Twelve target genes encoding proteins potentially involved in the response to heavy metal contamination with antioxidant, detoxification or apoptosis activities were selected. P. margaritifera accumulated Cd but not Cr, and mortality was related to the amount of Cd accumulated in tissues. In response to Cd-Cr contamination, metallothionein (MT) was significantly up-regulated by Cd-Cr at both concentrations, while 7 others (SOD, CAT, GPX, GSTO, GSTM, CASP, MDR) were down-regulated. Based on the development of these molecular tools, we propose that the pearl oyster, P. margaritifera, could be used as a sentinel species for heavy metal contamination in the lagoons of tropical ecosystems.
Afficher plus [+] Moins [-]The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms
2017
Kühn, Susanne | Werven, Van, Bernike | Oyen, Van, Albert | Meijboom, André | Bravo Rebolledo, Elisa L. | Franeker, Van, Jan A.
In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
Afficher plus [+] Moins [-]Modelling dispersal of radioactive contaminants in Arctic waters as a result of potential recovery operations on the dumped submarine K-27 Texte intégral
2017
Karcher, M. | Hosseini, A. | Schnur, R. | Kauker, F. | Brown, J.E. | Dowdall, M. | Strand, P.
Modelling dispersal of radioactive contaminants in Arctic waters as a result of potential recovery operations on the dumped submarine K-27 Texte intégral
2017
Karcher, M. | Hosseini, A. | Schnur, R. | Kauker, F. | Brown, J.E. | Dowdall, M. | Strand, P.
Of the wide variety of dumped objects containing radioactive materials in the Arctic seas, the submarine K-27 constitutes a major risk due to the large amount of highly enriched uranium onboard and its location in shallow waters. As the matter of potential operations involving raising of the submarine have entered the public arena, a priori assessment of the contamination in the Arctic marine environment that could result after a possible accident during such operations is a matter of some interest. The dispersion of contaminants within the Arctic has been assessed using a large scale hydrodynamic model for a series of plausible accident scenarios and locations under different oceanographic regimes. Results indicate that, depending primarily on the nature of a release (i.e. instantaneous or continuous), large areas of the Arctic marine environment will exhibit contamination to varying degrees.
Afficher plus [+] Moins [-]Modelling dispersal of radioactive contaminants in Arctic waters as a result of potential recovery operations on the dumped submarine K-27 Texte intégral
2017
Karcher, Michael | Hosseini, A. | Schnur, R. | Kauker, Frank | Brown, J.E. | Dowdall, M. | Strand, P.
Of the wide variety of dumped objects containing radioactive materials in the Arctic seas, the submarine K-27 constitutes a major risk due to the large amount of highly enriched uranium onboard and its location in shallow waters. As the matter of potential operations involving raising of the submarine have entered the public arena, a priori assessment of the contamination in the Arctic marine environment that could result after a possible accident during such operations is a matter of some interest. The dispersion of contaminants within the Arctic has been assessed using a large scale hydrodynamic model for a series of plausible accident scenarios and locations under different oceanographic regimes. Results indicate that, depending primarily on the nature of a release (i.e. instantaneous or continuous), large areas of the Arctic marine environment will exhibit contamination to varying degrees.
Afficher plus [+] Moins [-]An integrated method to evaluate and monitor the conservation state of coralligenous habitats: The INDEX-COR approach Texte intégral
2017
Sartoretto, Stéphane | Schohn, Thomas | Bianchi, Carlo Nike | Morri, Carla | Garrabou, Joaquim | Ballesteros, Enric | Ruitton, Sandrine | Verlaque, Marc | Daniel, Boris | Charbonnel, Eric | Blouet, Sylvain | David, Romain | Féral, Jean-Pierre | Gatti, Giulia
An integrated method to evaluate and monitor the conservation state of coralligenous habitats: The INDEX-COR approach Texte intégral
2017
Sartoretto, Stéphane | Schohn, Thomas | Bianchi, Carlo Nike | Morri, Carla | Garrabou, Joaquim | Ballesteros, Enric | Ruitton, Sandrine | Verlaque, Marc | Daniel, Boris | Charbonnel, Eric | Blouet, Sylvain | David, Romain | Féral, Jean-Pierre | Gatti, Giulia
A new method based on photographic sampling coupled with in situ observations was applied to 53 stations along the French Mediterranean coast, to assess the integrity of coralligenous reefs affected by different levels of anthropogenic pressure. The conservation state of the assemblages characterizing these habitats was then assessed by an index – the INDEX-COR – that integrates three metrics: (i) the sensitivity of the taxa to organic matter and sediment deposition, (ii) the observable taxonomic richness, and (iii) the structural complexity of the assemblages. The sensitivity of INDEX-COR was tested and showed good correlation with the Level of Pressure calculated for each station according to expert judgment and field observations.
Afficher plus [+] Moins [-]An integrated method to evaluate and monitor the conservation state of coralligenous habitats: The INDEX-COR approach Texte intégral
2017
Sartoretto, Stéphane | Schohn, T. | Bianchi, C. N. | Morri, C. | Garrabou, Joaquim | Ballesteros, Enric | Ruitton, Sandrine | Verlaque, Marc | Daniel, Boris | Charbonnel, Eric | Blouet, Sylvain | Romain, D. | Féral, J.P. | Gatti, Giulia
10 páginas, 3 figuras, 4 tablas. | A new method based on photographic sampling coupled with in situ observations was applied to 53 stations along the French Mediterranean coast, to assess the integrity of coralligenous reefs affected by different levels of anthropogenic pressure. The conservation state of the assemblages characterizing these habitats was then assessed by an index – the INDEX-COR – that integrates three metrics: (i) the sensitivity of the taxa to organic matter and sediment deposition, (ii) the observable taxonomic richness, and (iii) the structural complexity of the assemblages. The sensitivity of INDEX-COR was tested and showed good correlation with the Level of Pressure calculated for each station according to expert judgment and field observations. | We would like to thank the French Protected Marine Areas Agency (AAMP) for its financial support to this project (convention n°3211545/ F). We also thank the Marine Protected Areas involved in the INDEXFig. 3. Color-coded representation of the conservation state of coralligenous habitats along the coasts of Provence. Orange: poor status; yellow: moderate status; green: good status; blue: high status. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.) S. Sartoretto et al. Marine Pollution Bulletin xxx (xxxx) xxx–xxx 8 COR program for their technical support (boats and divers), especially the directors and the staff of the “Parc Marin de la Côte Bleue”, the “Observatoire Marin du Littoral des Maures” and the “Aire Marine Protégée de la Côte Agathoise”. This work was also supported by the ERA-NET (SeasEra) CIGESMED Program (contract 2014/3/3211985). | Peer reviewed
Afficher plus [+] Moins [-]Plastic debris straps on threatened blue shark Prionace glauca Texte intégral
2017
Colmenero, Ana I. | Barría, Claudio | Broglio, Elisabetta | García-Barcelona, Salvador
Plastic debris straps on threatened blue shark Prionace glauca Texte intégral
2017
Colmenero, Ana I. | Barría, Claudio | Broglio, Elisabetta | García-Barcelona, Salvador
Juveniles of blue shark Prionace glauca caught in pelagic longlines targeting tuna and swordfish in the Atlantic Ocean and the Mediterranean Sea were found entangled with plastic straps around their gill region. The plastic debris were identified as strapping bands and caused several degrees of injuries on the dorsal musculature and pectoral fins. They were also obstructing the gill slits probably causing breathing issues. These records were uploaded in the web site seawatchers.org, and highlight the potential of citizen science in revealing the occurrence of such problems which could help to measure the effects of plastic debris on marine life.
Afficher plus [+] Moins [-]Plastic debris straps on threatened blue shark Prionace glauca Texte intégral
2017
Colmenero, Ana I. | Barría, Claudio | Broglio, Elisabetta | García-Barcelona, Salvador | Fundación Española para la Ciencia y la Tecnología
3 pages, 1 figure, 1 table | Juveniles of blue shark Prionace glauca caught in pelagic longlines targeting tuna and swordfish in the Atlantic Ocean and the Mediterranean Sea were found entangled with plastic straps around their gill region. The plastic debris were identified as strapping bands and caused several degrees of injuries on the dorsal musculature and pectoral fins. They were also obstructing the gill slits probably causing breathing issues. These records were uploaded in the web site seawatchers.org, and highlight the potential of citizen science in revealing the occurrence of such problems which could help to measure the effects of plastic debris on marine life | This work was supported by the Fundación Española para la Ciencia y la Tecnología (FECYT) (FCT-15-9567) | Peer Reviewed
Afficher plus [+] Moins [-]The impact of submarine copper mine tailing disposal from the 1970s on Repparfjorden, northern Norway Texte intégral
2017
Sternal, Beata | Junttila, Juho | Skirbekk, Kari | Forwick, Matthias | Carroll, JoLynn | Pedersen, Kristine Bondo
The impact of submarine copper mine tailing disposal from the 1970s on Repparfjorden, northern Norway Texte intégral
2017
Sternal, Beata | Junttila, Juho | Skirbekk, Kari | Forwick, Matthias | Carroll, JoLynn | Pedersen, Kristine Bondo
We investigate the state of sedimentological environment and contaminant status of Repparfjorden (N Norway) impacted by submarine disposal of mine tailings during the 1970s using sedimentological and geochemical properties of seventeen sediment cores. The impact of tailings disposal is mainly restricted to the inner fjord where the discharge occurred. Sediment cores retrieved from the inner fjord contain layers of mine tailings up to 9-cm thick, 3–9cm below the seafloor. Spreading of the tailing-related metal Cu and particles is limited to the inner fjord and to a 2cm layer in one core from the outer fjord. Two interrelated factors, fjord morphology and sedimentation rate, controlled the distribution of contaminant-laden tailings in the fjord. The mobility of Cu from buried contaminated sediments to the sediment-water interface in the inner fjord indicates that benthic communities have been continuously exposed to elevated Cu concentrations for nearly four decades.
Afficher plus [+] Moins [-]The impact of submarine copper mine tailing disposal from the 1970s on Repparfjorden, northern Norway Texte intégral
2017
Sternal, Beata | Junttila, Juho | Skirbekk, Kari | Forwick, Matthias | Carroll, JoLynn | Pedersen, Kristine Bondo
Submitted manuscript version, licensed <a href=http://creativecommons.org/licenses/by-nc-nd/4.0/> CC BY-NC-ND 4.0. </a>Published version available at: <a href=http://doi.org/10.1016/j.marpolbul.2017.04.054> http://doi.org/10.1016/j.marpolbul.2017.04.054 </a> | We investigate the state of sedimentological environment and contaminant status of Repparfjorden (N Norway) impacted by submarine disposal of mine tailings during the 1970s using sedimentological and geochemical properties of seventeen sediment cores. The impact of tailings disposal is mainly restricted to the inner fjord where the discharge occurred. Sediment cores retrieved from the inner fjord contain layers of mine tailings up to 9-cm thick, 3–9 cm below the seafloor. Spreading of the tailing-related metal Cu and particles is limited to the inner fjord and to a 2 cm layer in one core from the outer fjord. Two interrelated factors, fjord morphology and sedimentation rate, controlled the distribution of contaminant-laden tailings in the fjord. The mobility of Cu from buried contaminated sediments to the sediment-water interface in the inner fjord indicates that benthic communities have been continuously exposed to elevated Cu concentrations for nearly four decades.
Afficher plus [+] Moins [-]Spatial and temporal distribution of mercury and methylmercury in bivalves from the French coastline Texte intégral
2017
Briant, N | Chouvelon, T | Martinez, L | Brach-Papa, C | Chiffoleau, JF | Savoye, N | Sonke, J | Knoery, J
Spatial and temporal distribution of mercury and methylmercury in bivalves from the French coastline Texte intégral
2017
Briant, N | Chouvelon, T | Martinez, L | Brach-Papa, C | Chiffoleau, JF | Savoye, N | Sonke, J | Knoery, J
Marine mercury (Hg) concentrations have been monitored in the French coastline for the last half a century using bivalves. The analyses presented in this study concerned 192 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from 77 sampling stations along the French coast and in the French Antilles sea. The goals of this study were to assess MeHg levels in various common bivalves from French coastline, and to identify possible geographic, taxonomic or temporal variations of concentrations. We show that the evolution of methylmercury (MeHg) concentrations covary with total mercury (HgT) concentrations. Moreover, in most of the study sites, HgT concentrations have not decreased since 1987, despite regulations to decrease or ban mercury used for anthropic activities.
Afficher plus [+] Moins [-]Spatial and temporal distribution of mercury and methylmercury in bivalves from the French coastline Texte intégral
2017
Briant, Nicolas | Chouvelon, Tiphaine | Martinez, Laura | Brach-papa, Christophe | Chiffoleau, Jean-francois | Savoye, N. | Sonke, J. | Knoery, Joel
Marine mercury (Hg) concentrations have been monitored in the French coastline for the last half a century using bivalves. The analyses presented in this study concerned 192 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from 77 sampling stations along the French coast and in the French Antilles sea. The goals of this study were to assess MeHg levels in various common bivalves from French coastline, and to identify possible geographic, taxonomic or temporal variations of concentrations. We show that the evolution of methylmercury (MeHg) concentrations covary with total mercury (HgT) concentrations. Moreover, in most of the study sites, HgT concentrations have not decreased since 1987, despite regulations to decrease or ban mercury used for anthropic activities.
Afficher plus [+] Moins [-]Ocean acidification increases larval swimming speed and has limited effects on spawning and settlement of a robust fouling bryozoan, Bugula neritina Texte intégral
2017
Pecquet, Antoine | Dorey, Narimane | Chan, Kit Yu Karen
Ocean acidification increases larval swimming speed and has limited effects on spawning and settlement of a robust fouling bryozoan, Bugula neritina Texte intégral
2017
Pecquet, Antoine | Dorey, Narimane | Chan, Kit Yu Karen
Few studies to date have investigated the effects of ocean acidification on non-reef forming marine invertebrates with non-feeding larvae. Here, we exposed adults of the bryozoan Bugula neritina and their larvae to lowered pH. We monitored spawning, larval swimming, settlement, and post-settlement individual sizes at two pHs (7.9 vs. 7.6) and settlement dynamics alone over a broader pH range (8.0 down to 6.5). Our results show that spawning was not affected by adult exposure (48h at pH7.6), larvae swam 32% faster and the newly-settled individuals grew significantly larger (5%) at pH7.6 than in the control. Although larvae required more time to settle when pH was lowered, reduced pH was not lethal, even down to pH6.5. Overall, this fouling species appeared to be robust to acidification, and yet, indirect effects such as prolonging the pelagic larval duration could increase predation risk, and might negatively impact population dynamics.
Afficher plus [+] Moins [-]Seawater carbonate chemistry and larval swimming speed, spawning and settlement of a robust fouling bryozoan, Bugula neritina Texte intégral
2017
Pecquet, Antoine | Dorey, Narimane | Chan, Kit Yu Karen
Few studies to date have investigated the effects of ocean acidification on non-reef forming marine invertebrates with non-feeding larvae. Here, we exposed adults of the bryozoan Bugula neritina and their larvae to lowered pH. We monitored spawning, larval swimming, settlement, and post-settlement individual sizes at two pHs (7.9 vs. 7.6) and settlement dynamics alone over a broader pH range (8.0 down to 6.5). Our results show that spawning was not affected by adult exposure (48 h at pH 7.6), larvae swam 32% faster and the newly-settled individuals grew significantly larger (5%) at pH 7.6 than in the control. Although larvae required more time to settle when pH was lowered, reduced pH was not lethal, even down to pH 6.5. Overall, this fouling species appeared to be robust to acidification, and yet, indirect effects such as prolonging the pelagic larval duration could increase predation risk, and might negatively impact population dynamics.
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