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Forests under climate change and air pollution: Gaps in understanding and future directions for research
2012
Matyssek, R. | Wieser, G. | Calfapietra, C. | de Vries, W. | Dizengremel, Pierre | Ernst, D. | Jolivet, Yves | Mikkelsen, T. N. | Mohren, G. M. J. | Le Thiec, Didier | Tuovinen, J. -P. | Weatherall, A. | Paoletti, E. | Technische Universität Munchen - Technical University Munich - Université Technique de Munich (TUM) | Dept Alpine Timberline Ecophysiol ; Federal Office and Research Centre for Forests | Natl Res Council ; Inst Agroenvironm & Forest Biol | Environm Syst Anal Grp ; Wageningen University and Research [Wageningen] (WUR) | Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Inst Biochem Plant Pathol ; Helmholtz Zentrum München = German Research Center for Environmental Health | Biosystems Division [Roskilde] ; Risø National Laboratory for Sustainable Energy (Risø DTU) ; Danmarks Tekniske Universitet = Technical University of Denmark (DTU)-Danmarks Tekniske Universitet = Technical University of Denmark (DTU) | Forest Ecology and Forest Management Group [Wageningen] ; Centre for Ecosystem Studies [Wageningen] ; Wageningen University and Research [Wageningen] (WUR)-Wageningen University and Research [Wageningen] (WUR) | Finnish Meteorological Institute (FMI) | Natl Sch Forestry ; Univ Cumbria | National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR) | EU Commission
Forests in Europe face significant changes in climate, which in interaction with air quality changes, may significantly affect forest productivity, stand composition and carbon sequestration in both vegetation and soils. Identified knowledge gaps and research needs include: (i) interaction between changes in air quality (trace gas concentrations), climate and other site factors on forest ecosystem response, (ii) significance of biotic processes in system response, (iii) tools for mechanistic and diagnostic understanding and upscaling, and (iv) the need for unifying modelling and empirical research for synthesis. This position paper highlights the above focuses, including the global dimension of air pollution as part of climate change and the need for knowledge transfer to enable reliable risk assessment. A new type of research site in forest ecosystems ("supersites") will be conducive to addressing these gaps by enabling integration of experimentation and modelling within the soil-plant-atmosphere interface, as well as further model development. (C) 2011 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Updated stomatal flux and flux-effect models for wheat for quantifying effects of ozone on grain yield, grain mass and protein yield
2012
Grünhage, Ludger, L. | Pleijel, Hakan, H. | Mills, Gina, G. | Bender, Jürgen, J. | Danielsson, Helena, H. | Lehmann, Yvonne, Y. | Castell, Jean-François, J.-F. | Bethenod, Olivier, O. | Department of Plant Ecology ; Justus-Liebig-Universität Gießen = Justus Liebig University (JLU) | Department of Plant and Environmental Sciences ; University of Gothenburg (GU) | Centre for Ecology and Hydrology [Bangor] (CEH) ; Natural Environment Research Council (NERC) | Institute of Biodiversity ; Johann Heinrich von Thünen-Institute | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Swedish Environment Protection Agency; Defra [AQ0810, AQ0816, AQ0601]; LRTAP Convention; NERC; French National Research Agency, ANR
Field measurements and open-top chamber experiments using nine current European winter wheat cultivars provided a data set that was used to revise and improve the parameterisation of a stomatal conductance model for wheat, including a revised value for maximum stomatal conductance and new functions for phenology and soil moisture. For the calculation of stomatal conductance for ozone a diffusivity ratio between O(3) and H(2)O in air of 0.663 was applied, based on a critical review of the literature. By applying the improved parameterisation for stomatal conductance, new flux-effect relationships for grain yield, grain mass and protein yield were developed for use in ozone risk assessments including effects on food security. An example of application of the flux model at the local scale in Germany shows that negative effects of ozone on wheat grain yield were likely each year and on protein yield in most years since the mid 1980s.
Afficher plus [+] Moins [-]Contrasting levels of heavy metals in the feathers of urban pigeons from close habitats suggest limited movements at a restricted scale
2012
Frantz, Adrien | Pottier, Marie-Anne | Karimi, Battle | Corbel, Hélène | Aubry, Emmanuel | Haussy, Claudy | Gasparini, Julien | Castrec-Rouelle, Maryse | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Centre National de la Recherche Scientifique | Universite Pierre Marie Curie
International audience | Despite restrictions in emissions, heavy metals may remain a major environmental issue due to their numerous sources and their persistence. Here, we assessed current levels of 4 metals (Copper, Cadmium, Lead, Zinc) in the feathers of 91 feral pigeons (Columba livia) from 7 sites in the urbanized region of Paris. Elements were detected in all pigeons, indicating that metals persist in urbanized areas. The ratio between metal concentrations in the feathers vs. in the environment calculated using data from other studies was 2-90 times higher for cadmium than for other metals, underlying its ecological importance. Concentrations in the feathers depended on locality, suggesting that pigeons remain in local habitats at this restricted scale, as expected from previous observations. Overall, our study suggests that urban feral pigeons may represent a good model system for metal biomonitoring. (c) 2012 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Diffuse urban pollution increases metal tolerance of natural heterotrophic biofilms
2012
Fechner, L.C. | Gourlay-Francé, C. | Bourgeault, A. | Tusseau-Vuillemin, M.H. | AgroParisTech | Hydrosystèmes et Bioprocédés (UR HBAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Laboratoire d’Oéanographie Spatiale [Plouzané] (LOS) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | This study is a first attempt to investigate the impact of urban contamination on metal tolerance of heterotrophic river biofilms using a short-term test based on β-glucosidase activity. Tolerance levels to Cu, Cd, Zn, Ni and Pb were evaluated for biofilms collected at three sites along an urban gradient in the Seine river (France). Metallic pollution increased along the river, but concentrations remained low compared to environmental quality standards. Biofilm metal tolerance increased downstream from the urban area. Multivariate analysis confirmed the correlation between tolerance and contamination and between multi-metallic and physico-chemical gradients. Therefore, tolerance levels have to be interpreted in relation to the whole chemical and physical characteristics and not solely metal exposure. We conclude that community tolerance is a sensitive biological response to urban pressure and that mixtures of contaminants at levels lower than quality standards might have a significant impact on periphytic communities.
Afficher plus [+] Moins [-]Towards a renewed research agenda in ecotoxicology
2012
Artigas, Joan | Arts, Gertie | Babut, Marc | Caracciolo, Anna Barra | Charles, Sandrine | Chaumot, Arnaud | Combourieu, Bruno | Dahllöf, Ingela | Despréaux, Denis | Ferrari, Benoit | Friberg, Nikolai | Garric, Jeanne | Geffard, Olivier | Gourlay-Francé, Catherine | Hein, Michaela | Hjorth, Morten | Krauss, Martin | de Lange, Hendrika J | Lahr, Joost | Lehtonen, Kari K | Lettieri, Teresa | Liess, Matthias | Lofts, Stephen | Mayer, Philipp | Morin, Soizic | Paschke, Albrecht | Svendsen, Claus | Usseglio-Polatera, Philippe | van den Brink, Nico | Vindimian, Eric | Williams, Richard | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Alterra [Wageningen] (ESS-CC) ; Centre for Water and Climate [Wageningen] | Modélisation et écotoxicologie prédictives ; Département biostatistiques et modélisation pour la santé et l'environnement [LBBE] ; Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE) ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM) ; Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS) | Institute of Bioscience ; Aarhus University [Aarhus] | Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Hydrosystèmes et Bioprocédés (UR HBAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | UFZ-Department of Bioanalytical Ecotoxicology ; Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research (UFZ) | Centre for Environmental Research ; Centre for Environmental Research | Institute for Environment and Sustainability, Rural, Water, and Ecosystem Resources Unit ; European Commission [Brussels] | UFZ-Department of System Ecotoxicology ; Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research (UFZ) | NERC Centre for Ecology and Hydrology ; Lancaster Environment Centre ; Lancaster University-Lancaster University | Institute of Environmental Sciences ; Aarhus University [Aarhus] | Department of Ecological Chemistry [Leipzig] ; Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research (UFZ) | NERC Centre for Ecology and Hydrology ; Natural Environment Research Council (NERC) | Laboratoire Biodiversité et Fonctionnement des Ecosystèmes (LBFE) ; Université Paul Verlaine - Metz (UPVM) | Services généraux (SGMO) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | New concerns about biodiversity, ecosystem services and human health triggered several new regulations increasing the need for sound ecotoxicological risk assessment. The PEER network aims to share its view on the research issues that this challenges. PEER scientists call for an improved biologically relevant exposure assessment. They promote comprehensive effect assessment at several biological levels. Biological traits should be used for Environmental risk assessment (ERA) as promising tools to better understand relationships between structure and functioning of ecosystems. The use of modern high throughput methods could also enhance the amount of data for a better risk assessment. Improved models coping with multiple stressors or biological levels are necessary to answer for a more scientifically based risk assessment. Those methods must be embedded within life cycle analysis or economical models for efficient regulations. Joint research programmes involving humanities with ecological sciences should be developed for a sound risk management.
Afficher plus [+] Moins [-]Which Hydraulic Model To Use In Vertical Flow Constructed Wetlands?
2012
Morvannou, A. | Forquet, N. | Vanclooster, M. | Molle, Pascal
Modeling water flow in a VFCW is a prerequisite to model wastewater treatment using process based filtering models. As for soils, when the vertical structure varies in different material types, it has a significant impact on water flow passing through it. The heterogeneous filtering material is composed of a mix of mineral porous material, and organic matter which makes its hydraulic characterization a difficult task. Indeed, the porosity may serve as preferential flow paths through which water can bypass most of the soil porous matrix in a largely unpredictable way. Consequently, non-equilibrium conditions in pressure heads are created between preferential flow paths and the soil matrix pore region. Preferential flows limit the applicability of standard models for water flow that are commonly based on Richards’ equation. Even if it is possible to simulate water content variations within a VFCW, we can not correctly model outflow with the standard van Genuchten-Mualem function. A number of various model approaches have been proposed to overcome this problem. These models mostly try to separately describe flow and transport in preferred flow paths and slow or stagnant pore regions. The objective of this study was to compare the various existing models simulating the preferential flows within the French VFCWs. Moreover, by assuming that several layers hydraulically different compose the VFCW, we tested at which layer(s) it is necessary to apply the non-equilibrium models. A tracer experiment was performed to evaluate the non-equilibrium degree. It was conducted on a 100 p.e. plant in operation since 2004. Monitoring consisted in measuring inlet and outlet flows, infiltration rates and water content at a time interval of 1 minute. We used the HYDRUS-1D software package containing various non-equilibrium flow modeling approaches. The physical non-equilibrium transport models were used to simulate outflow, the tracer breakthrough curve as well as water contents within a French-type VFCW. Physical non-equilibrium models include the dual-porosity model (mobile-immobile water model, with water content mass transfer or head mass transfer), and the dual-permeability model (matrix and fracture pore regions). We also applied a bimodal single-domain approach (Durner model) in order to see if it is actually necessary to use non-equilibrium models to effectively simulate VFCW outflow. Performance of the various non-equilibrium models (accuracy and limitation) was assessed by comparing the simulated and measured tracer fluxes using the mean square relative error (MSRE) of prediction. The comparison between measured and simulated tracer breakthrough curves indicates that the non-equilibrium (dual-porosity or dual-permeability model) approach seem to be the most appropriate for simulating preferential flow paths. In addition, simulations reveal that all layers participate in the preferential flow path process. These preferential flow paths are mainly due to the sludge layer that has been developed on the surface of VFCW since its start-up (swelling/shrinking during the feeding/rest periods) and to the network of roots and rhizomes present in it.
Afficher plus [+] Moins [-]Simulation d'un traçage dans un filtre planté à écoulement vertical pour le traitement des surverses de basin d'orage en utilisant HYDRUS-2D | Simulation Of Tracer Tests In Constructed Wetlands For Combined Sewer Overflow Treatment Using The Hydrus-2D (Cw2D / Cwm1) Software Package
2012
Meyer, D. | Fournel, J. | Forquet, N. | Molle, Pascal
The Hydrus-2D software package allows to display the interaction of processes in constructed wetlands. Whereas several types of constructed wetlands were simulated successfully, the results for combined sewer overflow treatment wetlands are less satisfying so far. Main reasons can be found in the high variations of feeding characteristics as well as in extended dry periods of several weeks. In preparation of model improvements by considering organic filtrates as nutrient source in dry periods it seems to be essential to display hydraulics and solute transports correctly by tracer test studies. This was done in column experiments in the past, but not for full-scale constructed wetlands due to operational challenges. The given study shows tracer test results in pilot-scale operation in two different ways. Obtained measurement results were simulated with 1D and 2D approaches. Simulation results show the importance of considering inlet and outlet placement inside the filter beds correctly.
Afficher plus [+] Moins [-]Betaproteobacteria dominance and diversity shifts in the bacterial community of a PAH-contaminated soil exposed to phenanthrene.
2012
Martin, Florence | Torelli, Stéphane | Le Paslier, Denis | Barbance, Agnès | Martin-Laurent, Fabrice | Bru, David | Geremia, Roberto | Blake, Gérard | Jouanneau, Yves | Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249) ; Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG) ; Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | Département de Chimie Moléculaire (DCM) ; Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS) | Genoscope - Centre national de séquençage [Evry] (GENOSCOPE) ; Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) | Agroécologie [Dijon] ; Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement | Laboratoire d'Ecologie Alpine (LECA) ; Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS) | Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE) ; Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
International audience | In this study, the PAH-degrading bacteria of a constructed wetland collecting road runoff has been studied through DNA stable isotope probing. Microcosms were spiked with (13)C-phenanthrene at 34 or 337 ppm, and bacterial diversity was monitored over a 14-day period. At 337 ppm, PAH degraders became dominated after 5 days by Betaproteobacteria, including novel Acidovorax, Rhodoferax and Hydrogenophaga members, and unknown bacteria related to Rhodocyclaceae. The prevalence of Betaproteobacteria was further demonstrated by phylum-specific quantitative PCR, and was correlated with a burst of phenanthrene mineralization. Striking shifts in the population of degraders were observed after most of the phenanthrene had been removed. Soil exposed to 34 ppm phenanthrene showed a similar population of degraders, albeit only after 14 days. Results demonstrate that specific Betaproteobacteria are involved in the main response to soil PAH contamination, and illustrate the potential of SIP approaches to investigate PAH biodegradation in soil.
Afficher plus [+] Moins [-]Embryotoxic and genotoxic effects of heavy metals and pesticides on early life stages of Pacific oyster (Crassostrea gigas)
2012
Mai, Hong Ngoc | Cachot, J. | Brune, J. | Geffard, Olivier | Belles, A. | Budzinski, H. | Morin, Brice | Environnements et Paléoenvironnements OCéaniques (EPOC) ; Observatoire aquitain des sciences de l'univers (OASU) ; Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-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) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA | International audience | This study evaluated embryotoxicity and genotoxicity of two dissolved metals copper and cadmium (Cu and Cd) and two pesticides (metolachlor and irgarol) occurring in Arcachon Bay (SW France) in Pacific oyster (Crassostrea gigas) larvae and investigated the relationship between those two endpoints. Embryotoxicity was measured by calculating the percentage of abnormal D-shaped larvae and genotoxicity was evaluated with DNA strand breaks using the comet assay. After 24 h exposure, significant increases of the percentage of abnormal D-larvae and the DNA strand breaks were observed from 0.1µg/L for Cu, 10 µg/L for Cd and 0.01 µg/L for both irgarol and metolachlor in comparison with the controls. A strong positive relationship between embryotoxicity and genotoxicity was recorded for Cu, Cd and metolachlor. The current study suggests that copper, irgarol and metolachlor can induce larval abnormalities and DNA damage in a population of exposed oysters at environmentally relevant concentrations.
Afficher plus [+] Moins [-]PCBs and DDTs in Stenella coeruleoalba dolphins from the French Mediterranean coastal environment (2007-2009): Current state of contamination
2012
Wafo, Emmanuel | Risoul, Véronique | Schembri, Thérèse | Lagadec, Véronique | Dhermain, Frank | Mama, Chacha | Portugal, Henri | Aix Marseille Université (AMU) | Laboratoire de chimie bactérienne (LCB) ; Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS) | Institut National de la Santé et de la Recherche Médicale (INSERM) | Institut Pythéas (OSU PYTHEAS) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS) | Clinique Vétérianire (Redon) ; Partenaires INRAE | Nutrition, obésité et risque thrombotique (NORT) ; Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM) | French organization "Agence de l'Eau Rhone-Mediterranee et Corse"
International audience | Organochlorinated compounds including PolyChloroBiphenyles, Dichloro-DiphenylTrichloroethan and metabolites are determinated in Stenella coeruleoalba (n = 37) stranded on the french Mediterranean coasts from 2007 till 2009. Studies are carried out on lung, muscle, kidney, liver, and blubber. The sought-after compounds are all detected to variable levels in each tissue and organ. In general, total PCBs are the most abondant, followed by total DDTs. The concentration (in ng g(-1) of lipid weight) in blubber of S. coeruleoalba, varied from 2,052 to 158,992 for PCBs and from 1,120 to 45,779 for DDTs. The ratios DDE/tDDTs are higher than 80% in almost all samples. The overall results of this work, compared to previous studies concerning the Mediterranean Sea, seems to confirm the tendency to a decrease of the contamination by organics compounds for the cetaceans in the Western Mediterranean Sea. (C) 2012 Elsevier Ltd. All rights reserved.
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