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Mechanisms of formation and reactivity of imogolite types material Full text
2012
Rose, Jérôme | Levard, Clément | Thill, Antoine | Masion, Armand | Chaurand, Perrine | Doelsch, Emmanuel | Basile-Doelsch, Isabelle | Bottero, Jean Yves
Reactivity of nanopar8cles represents a central issue for many laboratories around the world. Among many supported efforts the control of the morphology of nanopar8cles is mo8vated by the fact that morphology strongly influence the proper8es of the final products. Among the vast family of available nanopar8cles, imogolite is a clay nanotube for which perfect control of the diameter is possible. Imogolites were first observed in volcanic soils[1]. They are natural aluminosilicate nanotubes having the general formula (OH)3Al2O3SiOH with a 2 nm external diameter and up to micrometers in length. The impressive monodispersity in imogolite nanotube diameter has mo8vated research on their forma8on mechanism. Synthesis protocols to produce imogolite were quickly developed. Farmer et al. were the first to obtain synthe8c imogolite using low concentra8ons of AlCl3 and SiO 2 monomers as star8ng materials (millimolar concentra8ons of the reagents) [2]. However, the produc8on of large amount of imogolite or imogolite type materials remained challenging for long 8me. We will present our most recent results concerning the possibility to produce imogolite type materials from highly concentrated stock solu8ons. We will also detail the possibility to form double wall Al- Ge nanotubes and the different stages of their forma8on [3-7]. We will then detail the surface reac8vity of these nanotubes toward metals at he lab scale as well as in natural soil. (Résumé d'auteur)
Show more [+] Less [-]Influence of plankton concentration on gametogenesis and spawning of the black lip pearl oyster Pinctada margaritifera in Ahe atoll lagoon (Tuamotu archipelago, French polynesia) Full text
2012
Fournier, Jonathan | Levesque, Emmanuelle | Pouvreau, Stephane | Le Pennec, Marcel | Le Moullac, Gilles
Pearl culture industry represents one of the dominant business sector of French Polynesia. However, it still entirely relies on unpredictable spat collection success. Our aim was to assess the influence of natural plankton concentration fluctuations on maturation and spawning of the black lip pearl oyster Pinctada margaritifera, during a 4 months survey conducted in Ahe atoll lagoon. Plankton concentration was assessed by chlorophyll a extraction and by microscope counts while gonadic index, gonado-visceral dry weights and histology were used to measure pearl oysters reproduction activity. We found that (i) plankton concentration fluctuations were mainly related to wind regime, (ii) gametogenesis rate was mainly related to plankton concentration, (iii) spawning occurred when maximal gonad storage was reached. (iv) plankton concentration was the main spawning synchronizing factor. These results contribute explaining P. margaritifera spat collection variability in French Polynesian atoll lagoon. (C) 2012 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs Full text
2012
Galparsoro, Ibon | Connor, David W. | Borja, Angel | Aish, Annabelle | Amorim, Patricia | Bajjouk, Touria | Chambers, Caroline | Coggan, Roger | Dirberg, Guillaume | Ellwood, Helen | Evans, Douglas | Goodin, Kathleen L. | Grehan, Anthony | Haldin, Jannica | Howell, Kerry | Jenkins, Chris | Michez, Noemie | Mo, Giulia | Buhl-mortensen, Pal | Pearce, Bryony | Populus, Jacques | Salomidi, Maria | Sanchez, Francisco | Serrano, Alberto | Shumchenia, Emily | Tempera, Fernando | Vasquez, Mickael
Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs Full text
2012
Galparsoro, Ibon | Connor, David W. | Borja, Angel | Aish, Annabelle | Amorim, Patricia | Bajjouk, Touria | Chambers, Caroline | Coggan, Roger | Dirberg, Guillaume | Ellwood, Helen | Evans, Douglas | Goodin, Kathleen L. | Grehan, Anthony | Haldin, Jannica | Howell, Kerry | Jenkins, Chris | Michez, Noemie | Mo, Giulia | Buhl-mortensen, Pal | Pearce, Bryony | Populus, Jacques | Salomidi, Maria | Sanchez, Francisco | Serrano, Alberto | Shumchenia, Emily | Tempera, Fernando | Vasquez, Mickael
The EUNIS (European Union Nature Information System) habitat classification system aims to provide a common European reference set of habitat types within a hierarchical classification, and to cover all terrestrial, freshwater and marine habitats of Europe. The classification facilitates reporting of habitat data in a comparable manner, for use in nature conservation (e.g. inventories, monitoring and assessments), habitat mapping and environmental management. For the marine environment the importance of a univocal habitat classification system is confirmed by the fact that many European initiatives, aimed at marine mapping, assessment and reporting, are increasingly using EUNIS habitat categories and respective codes. For this reason substantial efforts have been made to include information on marine benthic habitats from different regions, aiming to provide a comprehensive geographical coverage of European seas. However, there still remain many concerns on its applicability as only a small fraction of Europe's seas are fully mapped and increasing knowledge and application raise further issues to be resolved. This paper presents an overview of the main discussion and conclusions of a workshop, organised by the MeshAtlantic project, focusing upon the experience in using the EUNIS habitats classification across different countries and seas, together with case studies. The aims of the meeting were to: (i) bring together scientists with exper_ience_in the use of the EUNIS marine classification and representatives from the European Environment Agency (EEA); (ii) agree on enhancements to EUNIS that ensure an improved representation of the European marine habitats; and (iii) establish practices that make marine habitat maps produced by scientists more consistent with the needs of managers and decision-makers. During the workshop challenges for the future development of EUNIS were identified, which have been classified into five categories: (1) structure and hierarchy; (2) biology; (3) terminology; (4) mapping; and (5) future development. The workshop ended with a declaration from the attendees, with recommendations to the EEA and European Topic Centre on Biological Diversity, to take into account the outputs of the workshop, which identify weaknesses in the current classification and include proposals for its modification, and to devise a process to further develop the marine component of the EUNIS habitat classification. (C) 2012 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs Full text
2012
Galparsoro, Ibon | Connor, David W. | Borja, Angel | Aish, Annabelle | Amorim, Patricia | Bajjouk, Touria | Chambers, Caroline | Coggan, Roger | Dirberg, Guillaume | Ellwood, Helen | Evans, Douglas | Goodin, Kathleen L. | Grehan, Anthony | Haldin, Jannica | Howell, K. L. (Kerry L.) | Jenkins, Chris | Michez, Noëmie | Mo, Giulia | Buhl-Mortensen, Pål | Pearce, B. (Bryony) | Populus, Jacques | Salomidi, Maria | Sánchez, Francisco | Serrano, Alberto | Shumchenia, Emily | Tempera, Fernando | Vasquez, Mickaël
The EUNIS (European Union Nature Information System) habitat classification system aims to provide a common European reference set of habitat types within a hierarchical classification, and to cover all terrestrial, freshwater and marine habitats of Europe. The classification facilitates reporting of habitat data in a comparable manner, for use in nature conservation (e.g. inventories, monitoring and assessments), habitat mapping and environmental management. For the marine environment the importance of a univocal habitat classification system is confirmed by the fact that many European initiatives, aimed at marine mapping, assessment and reporting, are increasingly using EUNIS habitat categories and respective codes. For this reason substantial efforts have been made to include information on marine benthic habitats from different regions, aiming to provide a comprehensive geographical coverage of European seas. However, there still remain many concerns on its applicability as only a small fraction of Europe’s seas are fully mapped and increasing knowledge and application raise further issues to be resolved. This paper presents an overview of the main discussion and conclusions of a workshop, organised by the MeshAtlantic project, focusing upon the experience in using the EUNIS habitats classification across different countries and seas, together with case studies. The aims of the meeting were to: (i) bring together scientists with experience in the use of the EUNIS marine classification and representatives from the European Environment Agency (EEA); (ii) agree on enhancements to EUNIS that ensure an improved representation of the European marine habitats; and (iii) establish practices that make marine habitat maps produced by scientists more consistent with the needs of managers and decision-makers. During the workshop challenges for the future development of EUNIS were identified, which have been classified into five categories: (1) structure and hierarchy; (2) biology; (3) terminology; (4) mapping; and (5) future development. The workshop ended with a declaration from the attendees, with recommendations to the EEA and European Topic Centre on Biological Diversity, to take into account the outputs of the workshop, which identify weaknesses in the current classification and include proposals for its modification, and to devise a process to further develop the marine component of the EUNIS habitat classification.
Show more [+] Less [-]Using EUNIS habitat classification for benthic mapping in European seas: Present concerns and future needs. Full text
2012
Galparsoro, D.W. | Connor, A. | Borja, Ángel | Aish, P. | Amorim, T. | Bajjouk, C. | Chambers, R. | Coggan, G. | Dirberg, H. | Ellwood, D. | Evans, D. | Goodin, K.L. | Grehan, Anthony | Haldin, J. | Howell, K. | Jenkins, C. | Michez, N. | Mo, G. | Buhl-Mortensen, Pal | Pearce, B. | Populus, J. | Salomidi, Maria | Sánchez, Francisco | Serrano, Alberto | Shumchenia, E. | Tempera, Fernando | Vásquez, M.
The EUNIS (European Union Nature Information System) habitat classification system aims to provide a common European reference set of habitat types within a hierarchical classification, and to cover all terrestrial, freshwater and marine habitats of Europe. The classification facilitates reporting of habitat data in a comparable manner, for use in nature conservation (e.g. inventories, monitoring and assessments), habitat mapping and environmental management. For the marine environment the importance of a univocal habitat classification system is confirmed by the fact that many European initiatives, aimed at marine mapping, assessment and reporting, are increasingly using EUNIS habitat categories and respective codes. For this reason substantial efforts have been made to include information on marine benthic habitats from different regions, aiming to provide a comprehensive geographical coverage of European seas. However, there still remain many concerns on its applicability as only a small fraction of Europe’s seas are fully mapped and increasing knowledge and application raise further issues to be resolved. This paper presents an overview of the main discussion and conclusions of a workshop, organised by the MeshAtlantic project, focusing upon the experience in using the EUNIS habitats classification across different countries and seas, together with case studies. The aims of the meeting were to: (i) bring together scientists with experience in the use of the EUNIS marine classification and representatives from the European Environment Agency (EEA); (ii) agree on enhancements to EUNIS that ensure an improved representation of the European marine habitats; and (iii) establish practices that make marine habitat maps produced by scientists more consistent with the needs of managers and decision-makers. During the workshop challenges for the future development of EUNIS were identified, which have been classified into five categories: (1) structure and hierarchy; (2) biology; (3) terminology; (4) mapping; and (5) future development. The workshop ended with a declaration from the attendees, with recommendations to the EEA and European Topic Centre on Biological Diversity, to take into account the outputs of the workshop, which identify weaknesses in the current classification and include proposals for its modification, and to devise a process to further develop the marine component of the EUNIS habitat classification. | Sí
Show more [+] Less [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Full text
2012
Harmelin-vivien, Mireille | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Veronique | Mellon, Capucine | Tronczynski, Jacek | Cossa, Daniel
Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Full text
2012
Harmelin-vivien, Mireille | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Veronique | Mellon, Capucine | Tronczynski, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and Cs-137) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (delta N-15). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and Cs-137, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants. (C) 2012 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Full text
2012
Harmelin-Vivien, M. L. (Mireille L.) | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Véronique | Mellon-Duval, Capucine | Tronczyński, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and ¹³⁷Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism’s trophic level (δ¹⁵N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and ¹³⁷Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.
Show more [+] Less [-]Evaluation of the partial renewal of in situ phytoplankton microcosms and application to the impact assessment of bentazon and dimethenamid Full text
2012
De La Broise, Denis | Stachowski-haberkorn, Sabine
Evaluation of the partial renewal of in situ phytoplankton microcosms and application to the impact assessment of bentazon and dimethenamid Full text
2012
De La Broise, Denis | Stachowski-haberkorn, Sabine
Microcosms, each consisting of 2 L natural surface seawater maintained in 2.3-L glass bottles, were immersed at a depth of 6 metres. The renewal of ten percent of microcosm volumes was carried out every other day. Phytoplankton-containing seawater was used for renewal (previously filtered through 25-, 50- or 200-μm cut-off). Phytoplankton community pigment analysis (by HPLC) and flow cytometry analysis were performed. After 13 days, data exhibited phytoplankton characteristics in microcosms in the same range as that of the natural surrounding sea water over the same period. Furthermore, in these microcosms, a negative correlation was observed between the filtration cut-off used for renewal water, and the eukaryote cell count. Herbicides were tested as commercial mixtures at 1, 10 and 100 μg.L-1 active principal. Both Frontier® (dimethenamid) and Basamais® (bentazon) induced significant modifications of the phytoplankton populations at every concentration tested. Such results suggest a possible disturbance in polluted coastal areas.
Show more [+] Less [-]Evaluation of the partial renewal of in situ phytoplankton microcosms and application to the impact assessment of bentazon and dimethenamid Full text
2012
de la Broise, Denis | Stachowski-Haberkorn, Sabine
Microcosms, each consisting of 2L natural surface seawater maintained in 2.3-L glass bottles, were immersed at a depth of 6m. The renewal of 10% of microcosm volumes was carried out every other day. Phytoplankton-containing seawater was used for renewal (previously filtered through 25-, 50- or 200-μm cut-off). Phytoplankton community pigment analysis (by HPLC) and flow cytometry analysis were performed. After 13days, data exhibited phytoplankton characteristics in microcosms in the same range as that of the natural surrounding sea water over the same period. Furthermore, in these microcosms, a negative correlation was observed between the filtration cut-off used for renewal water, and the total cell count. Herbicides were tested as commercial mixtures at 1, 10 and 100μgL⁻¹ active substance. Both Frontier® (dimethenamid) and Basamais® (bentazon) induced significant modifications of the phytoplankton populations at every concentration tested. Such results suggest a possible disturbance in polluted coastal areas.
Show more [+] Less [-]Effect of zinc sacrificial anode degradation on the defence system of the Pacific oyster, Crassostrea gigas: Chronic and acute exposures Full text
2012
Mottin, Elmina | Caplat, Christelle | Latire, Thomas | Mottier, Antoine | Mahaut, Marie-Laure | Costil, Katherine | Barillier, Daniel | Lebel, Jean-Marc | Serpentini, Antoine
Two types of exposures were performed to assess the effects of zinc released from sacrificial anode degradation: a chronic exposure, in which oysters were exposed to 0.53±0.04mgZnL⁻¹ for 10weeks, and an acute exposure, where oysters were exposed to 10.2±1.2mgZnL⁻¹ for 1week. At the end of the acute exposure experiment, 81.8% mortality was recorded. In contrast, no mortality was detected after 10weeks exposure. Moreover, all of the immune system biomarkers studied, except the number of circulating haemocytes, were stimulated by a moderate level of zinc and inhibited by a high level. Our exposure conditions did not induce SOD or MXR mRNA expression in gills and digestive gland. However, an increase of MT mRNA is observed in these tissues. The results indicate that oysters are sensitive to acute zinc toxicity but are only moderately affected by a mild zinc concentration.
Show more [+] Less [-]Assessing the potential underestimation of sediment and nutrient loads to the Great Barrier Reef lagoon during floods Full text
2012
Wallace, Jim | Karim, Fazlul | Wilkinson, Scott
Much of the sediment and nutrient load to the Great Barrier Reef (GBR) lagoon happens during over bank floods, when discharge can be significantly underestimated by standard river gauges. This paper assesses the potential need for a flood load correction for 28 coastal rivers that discharge into the GBR lagoon. For each river, daily discharge was divided into flows above and below a ‘flood’ threshold to calculate the mean annual percentage flow above this threshold. Most GBR rivers potentially need a flood load correction as over 15% of their mean annual flow occurs above the minor flood level; only seven rivers need little/no correction as their flood flows were less than 5% of the mean annual flow. Improved assessment of the true load of materials to the GBR lagoon would be an important contribution to the monitoring and reporting of progress towards Reef Plan and associated marine load targets.
Show more [+] Less [-]Oxidative stress, genotoxicity and histopathology biomarker responses in mullet (Mugil cephalus) and sea bass (Dicentrarchus labrax) liver from Bizerte Lagoon (Tunisia) Full text
2012
Ben Ameur, Walid | de Lapuente, Joaquin | El Megdiche, Yassine | Barhoumi, Badreddine | Trabelsi, Souad | Camps, Lydia | Serret, Joan | Ramos-López, David | Gonzalez-Linares, Javier | Driss, Mohamed Ridha | Borràs, Miquel
The aim of the study was to evaluate the impact of environmental contaminants on oxidative stress, genotoxic and histopathologic biomarkers in liver of mullet (Mugil cephalus) and sea bass (Dicentrarchus labrax) collected from a polluted coastal lagoon (Bizerte Lagoon) in comparison to a reference site (the Mediterranean Sea). Antioxidant enzyme activities were lower in fish from the polluted site compared with fish from the reference site, suggesting deficiency of the antioxidant system to compensate for oxidative stress. DNA damage was higher in both fish species from the contaminated site indicating genotoxic effects. The liver histopathological analysis revealed alterations in fish from Bizerte Lagoon. Hepatocytes from both fish species featured extensive lipid-type vacuolation and membrane disruption. Results suggest that the selected biomarkers in both fish species are useful for the assessment of pollution impacts in coastal environments influenced by multiple pollution sources.
Show more [+] Less [-]Assessment of the effects of a marine urban outfall discharge on caged mussels using chemical and biomarker analysis Full text
2012
de los Ríos, Ana | Juanes, J. A. (José A.) | Ortiz-Zarragoitia, Maren | López de Alda, Miren | Barceló, Damià | Cajaraville, Miren P.
To assess the presence of endocrine disruptors in treated marine outfall discharges and their possible effects, mussels (Mytilus galloprovincialis) were caged in the environmental mixing zone of the outfall of the Santander sanitation system and in one control area. After 30, 60 and 90days, samples were collected to perform chemical analyses (metals, anionic surfactants, alkylphenols, bisphenol A, phthalates and estrogenic hormones), biomarkers of general stress (lysosomal membrane stability-LMS, histopathology) and biomarkers of endocrine disruption (vitellogenin-like proteins and gonad index). There were no significant differences between outfall and control sites on contaminant levels, except for 4-tert-octylphenol which was higher in the outfall site. Bacteriological counts were higher in the outfall area. No relevant differences in biomarkers were detected between treated and control mussels. A significant reduction in LMS occurred in both groups after 90days caging, indicating a stress situation possibly related to caging or to post-spawning reproductive state.
Show more [+] Less [-]Numerical modelling of floating debris in the world’s oceans Full text
2012
Lebreton, L.C.-M. | Greer, S.D. | Borrero, J.C.
A global ocean circulation model is coupled to a Lagrangian particle tracking model to simulate 30years of input, transport and accumulation of floating debris in the world ocean. Using both terrestrial and maritime inputs, the modelling results clearly show the formation of five accumulation zones in the subtropical latitudes of the major ocean basins. The relative size and concentration of each clearly illustrate the dominance of the accumulation zones in the northern hemisphere, while smaller seas surrounded by densely populated areas are also shown to have a high concentration of floating debris. We also determine the relative contribution of different source regions to the total amount of material in a particular accumulation zone. This study provides a framework for describing the transport, distribution and accumulation of floating marine debris and can be continuously updated and adapted to assess scenarios reflecting changes in the production and disposal of plastic worldwide.
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