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Cellular distribution of metals in a liverwort and in a moss transplanted to two streams of differing acidity. Texte intégral
2008
Thiebaut, Gabrielle | Giamberini, Laure | Ghanbaja, Jaafar | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecotoxicité et santé environnementale (ESE) ; Université Paul Verlaine - Metz (UPVM)-Centre National de la Recherche Scientifique (CNRS) | Département de Chimie Physique des Réactions (DCPR) ; Institut National Polytechnique de Lorraine (INPL)-Centre National de la Recherche Scientifique (CNRS)
Cellular distribution of metals in a liverwort and in a moss transplanted to two streams of differing acidity. Texte intégral
2008
Thiebaut, Gabrielle | Giamberini, Laure | Ghanbaja, Jaafar | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecotoxicité et santé environnementale (ESE) ; Université Paul Verlaine - Metz (UPVM)-Centre National de la Recherche Scientifique (CNRS) | Département de Chimie Physique des Réactions (DCPR) ; Institut National Polytechnique de Lorraine (INPL)-Centre National de la Recherche Scientifique (CNRS)
International audience | To investigate the consequences of acidification and metal accumulation on the biology of aquatic bryophytes, the acid-tolerant liverwort Scapania undulata (L.) Dum. and the acid-sensitive moss Rhynchostegium riparioides (Hedw.) Cardot were transplanted from one stream to two other streams of differing acidity (pH 5.20 and 6.38). The bryophytes were collected in a circumneutral (pH 6.57) stream in the Vosges Mountains. Metal accumulation was semiquantitatively measured in shoots by energy dispersive TEM X-ray spectroscopy (EDXS). After 1 month, the two species remained green without alteration signs. Although no marked ultrastructural damage was observed in either species, some cells seemed to be necrotic, with flattened chloroplasts, in R. riparioides. Lipid droplet accumulation was observed in some leaf cells of S.undulata when transplanted to the most acidic stream. Metal was mostly localised in the cell wall, and was only sometimes detected in small vacuoles. Under acidic conditions, R. riparioides showed the highest relative amount of Al and the lowest amount of Fe, whereas the acid-tolerant bryophyte species S. undulata contained more Fe and less Al. The capability to limit the uptake of metals into the cytoplasm varies according to the bryophyte species. This could be an explanation of the tolerance of S. undulata to acidification.
Afficher plus [+] Moins [-]Cellular Distribution of Metals in a Liverwort and a Moss Transplanted to Two Streams of Differing Acidity Texte intégral
2008
Thiébaut, G. | Giamberini, L. | Ghanbaja, J.
To investigate the consequences of acidification and metal accumulation on the biology of aquatic bryophytes, the acid-tolerant liverwort Scapania undulata (L.) Dum. and the acid-sensitive moss Rhynchostegium riparioides (Hedw.) Cardot were transplanted from one stream to two other streams of differing acidity (pH 5.20 and 6.38). The bryophytes were collected in a circumneutral (pH 6.57) stream in the Vosges Mountains. Metal accumulation was semi-quantitatively measured in shoots by energy dispersive TEM X-ray spectroscopy (EDXS). After 1 month, the two species remained green without alteration signs. Although no marked ultrastructural damage was observed in either species, some cells seemed to be necrotic, with flattened chloroplasts, in R. riparioides. Lipid droplet accumulation was observed in some leaf cells of S.undulata when transplanted to the most acidic stream. Metal was mostly localised in the cell wall, and was only sometimes detected in small vacuoles. Under acidic conditions, R. riparioides showed the highest relative amount of Al and the lowest amount of Fe, whereas the acid-tolerant bryophyte species S. undulata contained more Fe and less Al. The capability to limit the uptake of metals into the cytoplasm varies according to the bryophyte species. This could be an explanation of the tolerance of S. undulata to acidification.
Afficher plus [+] Moins [-]Contamination of urban soils in an area of Northern France polluted by dust emissions of two smelters Texte intégral
2008
Douay, Francis | Pruvot, Christelle | Roussel, Hélène | Ciesielski, Henri, H. | Fourrier, Hervé | Proix, Nicolas | Waterlot, Christophe | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire d'Analyses des Sols (LAS) ; Institut National de la Recherche Agronomique (INRA)
Contamination of urban soils in an area of Northern France polluted by dust emissions of two smelters Texte intégral
2008
Douay, Francis | Pruvot, Christelle | Roussel, Hélène | Ciesielski, Henri, H. | Fourrier, Hervé | Proix, Nicolas | Waterlot, Christophe | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire d'Analyses des Sols (LAS) ; Institut National de la Recherche Agronomique (INRA)
Water Air Soil Poll 252WD Times Cited:37 Cited References Count:36 | International audience | The contamination of 27 urban topsoils has been assessed around two lead and zinc smelters (Metaleurop Nord and Umicore) in the North of France. Eighteen trace elements have been analysed (Ag, As, Bi, Cd, Co, Cr, Cu, Hg, In, Ni, Pb, Sb, Se, Sn, Tl, Th, U and Zn). The investigation included the study of the vertical distribution of Cd, Pb and Zn as indicators of pollution. It was shown that Cd, In, Pb, Sb and Zn were major pollutants followed in lesser quantities by Ag, Bi, Cu and Hg. In addition, As, Ni, Se, Sn and Tl were present at levels slightly higher than regional agricultural values. The other elements (Co, Cr, Th and U) were at endogenous levels. The observations have highlighted the strong heterogeneity of the physico-chemical parameters of urban soils and the existence of heavy contamination of the under layers by Cd, Pb and Zn. A potential transfer of metals from the topsoil to the deeper layers and especially Cd and Zn, is not excluded. Indeed the soil rework is not the only factor explaining contamination level of the deeper layers of the studied soils. The comparison of the studied element concentrations in urban soils with nearby local agricultural values shows that the dust emission originating from the Metaleurop and Umicore smelters were not the only source of contamination. Thus a large contamination of the studied urban soils by Sb and In could be explained by domestic combustion of coal for heating.
Afficher plus [+] Moins [-]Contamination of Urban Soils in an Area of Northern France Polluted by Dust Emissions of Two Smelters Texte intégral
2008
The contamination of 27 urban topsoils has been assessed around two lead and zinc smelters (Metaleurop Nord and Umicore) in the North of France. Eighteen trace elements have been analysed (Ag, As, Bi, Cd, Co, Cr, Cu, Hg, In, Ni, Pb, Sb, Se, Sn, Tl, Th, U and Zn). The investigation included the study of the vertical distribution of Cd, Pb and Zn as indicators of pollution. It was shown that Cd, In, Pb, Sb and Zn were major pollutants followed in lesser quantities by Ag, Bi, Cu and Hg. In addition, As, Ni, Se, Sn and Tl were present at levels slightly higher than regional agricultural values. The other elements (Co, Cr, Th and U) were at endogenous levels. The observations have highlighted the strong heterogeneity of the physico-chemical parameters of urban soils and the existence of heavy contamination of the under layers by Cd, Pb and Zn. A potential transfer of metals from the topsoil to the deeper layers and especially Cd and Zn, is not excluded. Indeed the soil rework is not the only factor explaining contamination level of the deeper layers of the studied soils. The comparison of the studied element concentrations in urban soils with nearby local agricultural values shows that the dust emission originating from the Metaleurop and Umicore smelters were not the only source of contamination. Thus a large contamination of the studied urban soils by Sb and In could be explained by domestic combustion of coal for heating.
Afficher plus [+] Moins [-]Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Texte intégral
2008
Fernandes, Denise | Andreu-Sánchez, Oscar | Bebianno, Maria Joao | Porte, Cinta
Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Texte intégral
2008
Fernandes, Denise | Andreu-Sánchez, Oscar | Bebianno, Maria Joao | Porte, Cinta
Muscle concentrations of organochlorinated compounds as well as biliary levels of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APEs) were determined in two different fish species, the four-spotted megrim (Lepidorhombus boscii) and the pouting (Trisopterus luscus) collected along the Northern Iberian coast. Additionally, a set of biochemical markers namely, 7-ethoxyresorufin O-deethylase (EROD), UDP-glucuronosyltransferase (UGT) and catalase (CAT) were measured in liver subcellular fractions. Chemical analysis indicated geographical differences in pollutant loads that were further reinforced by biomarker responses. Thus, EROD activity showed a good correlation with the amount of PCBs bioaccumulated in muscle tissue of both fish species. Elevated UGT activity was observed in those individuals highly exposed to APEs and 1-naphthol. The study reinforces the need to select representative sentinel species from different habitats for biomonitoring purposes and provides further support for the use of biomarkers in assessing the health of coastal areas.
Afficher plus [+] Moins [-]Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species Texte intégral
2008
Fernandes, D | Andreu-Sánchez, Oscar | Bebianno, Maria João | Porte, Cinta
Muscle concentrations of organochlorinated compounds as well as biliary levels of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APEs) were determined in two different fish species, the four-spotted megrim (Lepidorhombus boscii) and the pouting (Trisopterus luscus) collected along the Northern Iberian coast. Additionally, a set of biochemical markers namely, 7-ethoxyresorufin O-deethylase (EROD), UDP-glucuronosyltransferase (UGT) and catalase (CAT) were measured in liver subcellular fractions. Chemical analysis indicated geographical differences in pollutant loads that were further reinforced by biomarker responses. Thus, EROD activity showed a good correlation with the amount of PCBs bioaccumulated in muscle tissue of both fish species. Elevated UGT activity was observed in those individuals highly exposed to APEs and 1-naphthol. The study reinforces the need to select representative sentinel species from different habitats for biomonitoring purposes and provides further support for the use of biomarkers in assessing the health of coastal areas. | Spanish Government BES-2003-0163, Spanish National Plan for Research VEM2003-20068-C05-01 | info:eu-repo/semantics/publishedVersion
Afficher plus [+] Moins [-]PCDD/F and PCB multi-media ambient concentrations, congener patterns and occurrence in a Mediterranean coastal lagoon (Etang de Thau, France) Texte intégral
2008
Castro Jimenez, Javier | Deviller, Genevieve | Ghiani, A | Loos, R | Mariani, G | Skejo, H | Umlauf, G | Wollgast, J | Laugier, Thierry | Heas Moisan, K | Leaute, Frederique | Munschy, Catherine | Tixier, Celine | Tronczynski, Jacek
PCDD/F and PCB multi-media ambient concentrations, congener patterns and occurrence in a Mediterranean coastal lagoon (Etang de Thau, France) Texte intégral
2008
Castro Jimenez, Javier | Deviller, Genevieve | Ghiani, A | Loos, R | Mariani, G | Skejo, H | Umlauf, G | Wollgast, J | Laugier, Thierry | Heas Moisan, K | Leaute, Frederique | Munschy, Catherine | Tixier, Celine | Tronczynski, Jacek
Ambient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment and mussels in a semi-enclosed marine ecosystem (Thau lagoon, France). Sigma 2,3,7,8-PCDD/F and Sigma 7ICES PCB air concentrations (0.2-1.4 and 31-57 pg m(-3), respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476 fg L-1) and low for PCBs (138-708 pg L-1). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33 ng g(-1) d.w., respectively) and mussel (13-21 pg g(-1) d.w. and 10-39 ng g(-1) d.w., respectively) were medium levels. PCDD/F congener patterns observed in air, water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fs into the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs in the mentioned compartments. (C) 2007 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]PCDD/F and PCB Multi-media Ambient Concentrations, Congener Patterns and Occurrence in a Mediterranean Coastal Lagoon (Etang de Thau, France) Texte intégral
2007
CASTRO JIMENEZ Javier | DEVILLER Genevieve | GHIANI Michela | LOOS Robert | MARIANI Giulio | SKEJO Helle | UMLAUF Gunther | WOLLGAST Jan | LAUGIER T. | HEAS-MOISAN K. | LEAUTE F. | MUNSCHY C. | TIXIER C. | TRONCZYNSKI J.
Ambient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment and mussels in a semi-enclosed marine ecosystem (Thau lagoon, France). �2,3,7,8- PCDD/Fs and �7PCBs air concentrations (0.2-1.4 and 31-57 pg m-3, respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476 fg l-1) and low for PCBs (138-708 pg l-1). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33 ng g-1 d.w., respectively) and mussel (13-21 pg g-1 d.w. and 10-39 ng g-1 d.w., respectively) were medium levels. PCDD/F congener patterns observed in air, water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fs into the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs. A different behavior regarding the uptake of PCDD/Fs and PCBs by lagoon mussels was observed | JRC.H.5 - Rural, water and ecosystem resources
Afficher plus [+] Moins [-]Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: Geographical trends, causal factors and effects on reproduction and mortality Texte intégral
2008
Pierce, G | Santos, M | Murphy, S | Learmonth, J | Zuur, A | Rogan, E | Bustamante, Paco | Caurant, Florence | Lahaye, V | Ridoux, Vincent | Zegers, B | Mets, A | Addink, M | Smeenk, C | Jauniaux, T | Law, R | Dabin, W | Lopez, A | Farre, J | Gonzalez, A | Guerra, A | Garcia Hartmann, M | Reid, R | Moffat, C | Lockyer, C | Boon, J
Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: Geographical trends, causal factors and effects on reproduction and mortality Texte intégral
2008
Pierce, G | Santos, M | Murphy, S | Learmonth, J | Zuur, A | Rogan, E | Bustamante, Paco | Caurant, Florence | Lahaye, V | Ridoux, Vincent | Zegers, B | Mets, A | Addink, M | Smeenk, C | Jauniaux, T | Law, R | Dabin, W | Lopez, A | Farre, J | Gonzalez, A | Guerra, A | Garcia Hartmann, M | Reid, R | Moffat, C | Lockyer, C | Boon, J
Concentrations of polychlorinated biphenyls (PCBs) in blubber of female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the Southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. (C) 2007 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: Geographical trends, causal factors and effects on reproduction and mortality Texte intégral
2008
Pierce, Graham J. | González, Ángel F. | Guerra, Ángel
15 páginas, 6 tablas, 3 figuras.-- G. J. Pierce ... et al. | Concentrations of polychlorinated biphenyls (PCBs) in blubber of female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. | This work formed part of the EU-funded BIOCET project (Bioaccumulation of persistent organic pollutants in small cetaceans in European waters: transport pathways and impact on reproduction, EVK3-2000-00027). | Peer reviewed
Afficher plus [+] Moins [-]Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: geographical trends, causal factors and effects on reproduction and mortality. Texte intégral
2008
Pierce, Graham J. | Santos, María Begoña | Murphy, S. | Learmonth, Jennifer | Zuur, A.F. | Rogan, Emer | Bustamante, Paco | Caurant, Florence | Lahaye, V. | Ridoux, Vincent | Zegers, B.N. | Mets, A. | Addink, M. | Smeenk, C. | Jauniaux, T. | Law, R.J. | Dabin, W. | López, A. | Alonso-Farré, J. M. | González, Ángel | Guerra, Ángel | García-Hartmann, M. | Reid, Robert | Moffat, C.F. | Lockyer, Christina | Boon, J.P.
Concentrations of polychlorinated biphenyls (PCBs) in blubber of female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition | Sí
Afficher plus [+] Moins [-]Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: geographical trends, causal factors and effects on reproduction and mortality Texte intégral
2008
Pierce, G. J. | Santos, M. B. | Murphy, S. | Learmonth, J. A. | Zuur, A. F. | Rogan, E. | Bustamante, P. | Caurant, F. | Lahaye, V. | Ridoux, V. | Zegers, B. N. | Mets, A. | Addink, M. | Smeenk, C. | Jauniaux, Thierry | Law, R. J. | Dabin, W. | Lopez, A. | Alonso Farre, J. M. | Gonzales, A. V. | Guerra, A. | Garcia-Hartmann, M. | Reid, R. J. | Moffat, C. F. | Lockyer, C.
peer reviewed | female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. High PCB levels were recorded in porpoises and common dolphins from European coasts.
Afficher plus [+] Moins [-]Reducing power dependent on metabolic changes as an indicator for ozone effective phytotoxicity Texte intégral
2008
Dizengremel, Pierre, | Jolivet, Yves, | Le Thiec, Didier, | Hasenfratz-Sauder, Marie-Paule | Bagard, Mathieu
Influence of oyster culture practices and environmental conditions on the ecological status of intertidal mudflats in the Pertuis Charentais (SW France): A multi-index approach Texte intégral
2008
Bouchet, Vincent | Sauriau, Pierre-guy
The ecological quality status (EcoQ) of intertidal mudflats constrained by Pacific oyster farming was assessed by single (H', AMBI, BENTIX and BOPA) and multimetric (M-AMBI and average score) index approaches in the Pertuis Charentais (SW France). Fifteen sampling stations were monitored seasonally for sedimentological features and macrozoobenthos in 2004. Sediments affected by oyster biodeposits showed organic matter enrichment, and sediments from off-bottom culture sites had higher organic matter contents and lower redox potentials than sediments from on-bottom culture sites. Biotic indices consistently registered responses of macrozoobenthos to organic enrichment but there was only partial agreement between single index-derived EcoQs. The average score was better than M-AMBI and single indices for determining EcoQs. Accordingly, oyster farming alters intertidal macrozoobenthic assemblages moderately, and off-bottom cultures cause more disturbance than on-bottom cultures. Hydrodynamics and seasons may interact with culture practices in smothering/strengthening biodeposition-mediated effects through dispersal/accumulation of biodeposits.
Afficher plus [+] Moins [-]Water-use efficiency in trees : techniques, scales and diversity Texte intégral
2008
Dreyer, Erwin | Brendel, Oliver | Roussel, Magali | Douthe, Cyril, | Epron, Daniel, | Guehl, Jean-Marc,
Water-use efficiency is an important functional trait that can be defined at very different temporal and spatial scales in trees as well as in crops. Transpiration efficiency (TE) is usually defined at tree or even stand level as the ratio between transpired water and accumulated biomass. Intrinsic water-use efficiency (Wi) is defined at instant leaf scale as the ratio net CO2 assimilation rate vs. stomatal conductance (A/gs). Wi is usually estimated by isotopic discrimination against 13CO2 during photosynthesis (Delta). Delta can be measured at the instantaneous time-scale on-line with new spectroscopic techniques, but is usually recorded from the isotopic composition of different metabolic pools (bulk leaf matter, soluble sugars, cellulose in leaves and wood). Delta is a plastic trait and is therefore largely used as an index for short term (interannual) changes in water availability and for climate constraints. Delta is also under tight genetic control in trees like in many other species and shows a large diversity. This was shown for populations from different origins, within populations on ecological clines, and among clones. Furthermore, quantitative genetics approaches identified a few highly significant QTLs for Delta in full-sib offsprings of oaks, maritime pine, chestnut and poplars, and thus identified a small number of genomic regions that are active in the control of Delta. The range of genotypic values identified in these approaches encompasses up to 3-4 ‰, which would translate into 30-50% difference in intrinsic water-use efficiency. Due to technical difficulties, much less evidence is available about the genetic control of Wi and of TE. Moreover, the parameters of the model relating Delta to Wi may also display some degree of genotypic variability, and the suitability of Delta as an index for Wi has been questioned. In this presentation, some evidence will be produced in support for the tight correlation between Delta and Wi in support of the use of Delta as a screening tool for Wi and even TE. Based on the accumulated data demonstrating the large diversity of Wi as well as the tight genetic control over this trait, a few research perspectives will be identified and discussed
Afficher plus [+] Moins [-]Cs-137 baseline levels in the Mediterranean and Black Sea: A cross-basin survey of the CIESM Mediterranean Mussel Watch programme Texte intégral
2008
Thebault, Herve | Baena, A | Andral, Bruno | Barisic, D | Albaladejo, J | Bologa, A | Boudjenoun, R | Delfanti, R | Egorov, V | Khoukhi, T | Florou, H | Kniewald, G | Noureddine, A | Patrascu, V | Pham, M | Scarpato, A | Stokozov, N | Topcuoglu, S | Warnau, M
Cs-137 baseline levels in the Mediterranean and Black Sea: A cross-basin survey of the CIESM Mediterranean Mussel Watch programme Texte intégral
2008
Thebault, Herve | Baena, A | Andral, Bruno | Barisic, D | Albaladejo, J | Bologa, A | Boudjenoun, R | Delfanti, R | Egorov, V | Khoukhi, T | Florou, H | Kniewald, G | Noureddine, A | Patrascu, V | Pham, M | Scarpato, A | Stokozov, N | Topcuoglu, S | Warnau, M
The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify Cs-137 levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While: measured Cs-137 levels were found to be very low (usually <1 Bq kg(-1) wet wt) Cs-137 activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. (C) 2007 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]137Cs baseline levels in the Mediterranean and Black Sea: A cross-basin survey of the CIESM Mediterranean Mussel Watch programme Texte intégral
2008
Thébault, H. | Baena, A.M., Rodriguez y | Andral, B. | Barisic, D. | Albaladejo, J.B. | Bologa, A.S. | Boudjenoun, R. | Delfanti, R. | Egorov, V.N. | El Khoukhi, T. | Florou, H. | Kniewald, G. | Noureddine, A. | Patrascu, V. | Pham, M.K. | Scarpato, A. | Stokozov, N.A. | Topcuoglu, S. | Warnau, M. | Laboratoire d'étude radioécologique du milieu continental et marin (IRSN/DEI/SESURE/LERCM) ; Service d'étude et de surveillance de la radioactivité dans l'environnement (IRSN/DEI/SESURE) ; Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN) | Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Center for Marine and Environmental Research ; Rudjer Boskovic Institute [Zagreb] | Instituto Español de Oceanografía - Spanish Institute of Oceanography (IEO) ; Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC) | National Institute for Marine Research and Development "Grigore Antipa" (NIMRD) | Agenzia Nazionale per le nuove Tecnologie, l’energia e lo sviluppo economico sostenibile = Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) | NATIONAL ACADEMY OF SCIENCES OF THE UKRAINE KHARKOV UKR ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Centre National de l'Énergie, des Sciences et des Techniques Nucléaires = National Center for Energy, Science and Nuclear Techniques (CNESTEN) | National Center for Scientific Research "Demokritos" (NCSR) | Marine Environment Laboratories [Monaco] (IAEA-MEL) ; International Atomic Energy Agency [Vienna] (IAEA) | I.C.R.A.M. - Central Institute for Applied Marine Research ; I.C.R.A.M. - Central Institute for Applied Marine Research
International audience | The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1 Bq kg-1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. © 2007 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Cellular distribution of metals in a liverwort and in a moss transplanted to two streams of differing acidity. Texte intégral
2008
Thiebaut, Gabrielle | Giamberini, Laure | Ghanbaja, Jaafar
To investigate the consequences of acidification and metal accumulation on the biology of aquatic bryophytes, the acid-tolerant liverwort Scapania undulata (L.) Dum. and the acid-sensitive moss Rhynchostegium riparioides (Hedw.) Cardot were transplanted from one stream to two other streams of differing acidity (pH 5.20 and 6.38). The bryophytes were collected in a circumneutral (pH 6.57) stream in the Vosges Mountains. Metal accumulation was semiquantitatively measured in shoots by energy dispersive TEM X-ray spectroscopy (EDXS). After 1 month, the two species remained green without alteration signs. Although no marked ultrastructural damage was observed in either species, some cells seemed to be necrotic, with flattened chloroplasts, in R. riparioides. Lipid droplet accumulation was observed in some leaf cells of S.undulata when transplanted to the most acidic stream. Metal was mostly localised in the cell wall, and was only sometimes detected in small vacuoles. Under acidic conditions, R. riparioides showed the highest relative amount of Al and the lowest amount of Fe, whereas the acid-tolerant bryophyte species S. undulata contained more Fe and less Al. The capability to limit the uptake of metals into the cytoplasm varies according to the bryophyte species. This could be an explanation of the tolerance of S. undulata to acidification. | International audience
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