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Applications of C and N stable isotopes to ecological and environmental studies in seagrass ecosystems Full text
2004
Lepoint, Gilles | Dauby, Patrick | Gobert, Sylvie | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Stable isotopes of carbon and nitrogen are increasingly used in marine ecosystems, for ecological and environmental studies. Here, we examine some applications of stable isotopes as ecological integrators or tracers in seagrass ecosystem studies. We focus on both the use of natural isotope abundance as food web integrators or environmental tracers and on the use of stable isotopes as experimental tools. As ecosystem integrators, stable isotopes have helped to elucidate the general structure of trophic webs in temperate, Mediterranean and tropical seagrass ecosystems. As environmental tracers, stable isotopes have proven their utility in sewage impact measuring and mapping. However, to make such environmental studies more comprehensible, future works on understanding of basic reasons for variations of N and C stable isotopes in seagrasses should be encouraged. At least, as experimental tracers, stable isotopes allow the study of many aspects of N and C cycles at the scale of a plant or at the scale of the seagrass ecosystem. (C) 2004 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Nitrogen dynamics in Posidonia oceanica cuttings: implications for transplantation experiments Full text
2004
Lepoint, Gilles | Vangeluwe, Denis | Eisinger, Michael | Paster, Marcus | van Treeck, Peter | Bouquegneau, Jean-Marie | Gobert, Sylvie | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | A N-15 tracer study was performed during an experimental transplantation trial of natural Posidonia oceanica cuttings. The experiment was done in situ at 17 m depth in the Revellata Bay (Calvi, NW Corsica, France). Despite high survival rates of transplants (>90%) after one year, the weight and the N content of transplants are significantly lower than those of reference plants. In absence of roots, the transplants are not able to meet their N requirement because, leaf uptake is insufficient to replenish the N lost during the natural leaf decay. This could constitute a major cause of long-term failure for transplantation experiments or natural recolonisation processes. The increase of the N-15 content in the roots shows that the plant re-allocates the nitrogen of one organ (i.e. leaves, rhizomes) to ensure the growth of another (i.e. roots). (C) 2003 Elsevier Ltd. All rights reserved. | Novel Marine Technology (NOMATEC)
Show more [+] Less [-]Quantification des pertes ammoniacales issues des épandages de lisiers en Bretagne : recherche de moyens pour les prévenir | Ammonia emissions following spreading of slurries in Britanny : ways to control Full text
1993
Moal, J.F. | Martinez, José | Guiziou, Fabrice | Caudal, M.C.
Les émissions d'ammoniac vers l'atmosphère, consécutives aux épandages de lisiers de porcs, ont été quanitifiées à l'aide de tunnels de ventilation. Ces appareils permettent la circulation de l'air en surface de la micro-parcelle expérimentale (1m2) qui reçoit l'apport de lisier. L'échantillonnage de l'air en sortie du tunnel (piégeage dans une solution acide) permet de quantifier l'ammoniac qui se dégage. Plusieurs essais, réalisés dans les quatre départements bretons au cours de l'année 1993, ont permis de mettre en évidence des pertes d'ammoniac allant de 5 à 63% de l'azote ammoniacal apporté par le lisier. Les résultats témoignent également de l'importance et de la rapidité du processus dans les premières heures qui suivent l'épandage : 72% des pertes totales mesurées ont eu lieu durant les 12 premières heures. Les émissions d'ammoniac sur ces 12 premières heures étaient notamment corrélées à la température (r=0,790) et à la dose d'azote ammoniacal apportée (kg N-NH4+/ha) (r=0,762). Afin d'envisager des voies de réduction de ce type d'émissions gazeuses, des essais réalisés au laboratoire en cellule de mesure ont été mis en place. L'acidifiction préalable du lisier à pH 6,5 (ajout d'HCL 10N) ainsi que l'ajout de chlorure de calcium (CaCl2,2H20) à hauteur de 92 g/l ont permis de réduire le processus de volatilisation d'ammoniac de 85% environ. | Ammonia emissions from surface-applied pig and cattle slurry were measured using a system of win tunnels. Field experiments carried out in Brittany (west of France) in 1993, shows ammonia losses ranging from 5 to 63% of the total ammoniacal nitrogen applied. On average 72% of the total losses occured within the first 12 hours after spreading. During this period, ammonia losses are closely correlated with temperature and the nitrogen rate applied. Laboratory experiments demonstrate the effects of the acidification and addition of calcium chloride (Cacl2,2H20) to the slurry which allows a 85% reduction of ammonia loss.
Show more [+] Less [-]Interet de la teledetection pour l'estimation et le suivi des dommages forestiers Full text
1993
RIOM, J. | Guyon, D.
Two-dimensional solute transport with exponential initial concentration distribution and varying flow velocity
2019
Thakur, C.K. | Chaudhary, M. | Zee, van der, S.E.A.T.M. | Singh, M.K.
The transport mechanism of contaminated groundwater has been a problematic issue for many decades, mainly due to the bad impact of the contaminants on the quality of the groundwater system. In this paper, the exact solution of two-dimensional advection-dispersion equation (ADE) is derived for a semi-infinite porous media with spatially dependent initial and uniform/flux boundary conditions. The flow velocity is considered temporally dependent in homogeneous media however, both spatially and temporally dependent is considered in heterogeneous porous media. First-order degradation term is taken into account to obtain a solution using Laplace Transformation Technique (LTT) for both the medium. The solute concentration distribution and breakthrough are depicted graphically. The effect of different transport parameters is studied through proposed analytical investigation. Advection-dispersion theory of contaminant mass transport in porous media is employed. Numerical solution is also obtained using Crank Nicholson method and compared with analytical result. Furthermore, accuracy of the result is discussed with root mean square error (RMSE) for both the medium. This study has developed a transport and prediction 2-D model that allows the early remediation and removal of possible pollutant in both the porous structures. The result may also be used as a preliminary predictive tool for groundwater resource and management.
Show more [+] Less [-]Pollution
1990
Harrison, R. M. (Roy M)
Much has happened in the pollution field since 1982 when the first edition of this work was written. This edition includes new subject areas such as radioactive pollution and chemistry and pollution of the stratosphere.
Show more [+] Less [-]Microplastic contamination of sediment and water column in the Seine River Estuary | Contamination en microplastiques dans les sédiment et colonne d'eau de l'estuaire de la Seine Full text
2019
Alligant, Soline | Gasperi, Johnny | Rakwe, El | Dreanno, Catherine | Gangnery, Aline | Maheux, Frank | Simon, Benjamin | Halm-Lemeille, Marie-Pierre | Cachot, Jérôme | Tassin, Bruno | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Laboratoire Environnement Ressources de Normandie (LERN) ; Unité Observation et écologie de la restauration des écosystèmes littoraux (COAST) ; Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Proceedings of the 2nd International Conference on Microplastic Pollution in the Mediterranean Sea, Capri, ITALIE, 15-/09/2019 - 18/09/2019 | International audience | Nowadays, microplastic (MPs) pollution is well documented in marine ecosystems since the first publication alarming about marine plastic pollution in 1972 [1]. Similarly, continental contamination is more and more investigated. More recently, interest for estuarine systems is growing. Estuaries are considered as a suspected predominant pathway for microplastic pollution from continent to oceans. The specific conditions of estuaries, like salinity gradient, tides and hydrodynamics, could affect the repartition, settling and transfer of microplastics to marine systems.
Show more [+] Less [-]13C assimilation as well as functional gene abundance and expression elucidate the biodegradation of glyphosate in a field experiment Full text
2022
Wirsching, Johannes | Wimmer, Benedikt | Ditterich, Franziska | Schlögl, Johanna | Martin-Laurent, Fabrice | Huhn,, Carolin | Haderlein, Stefan, B. | Kandeler, Ellen | Poll, Christian | University of Stuttgart, Germany | Eberhard Karls University of Tübingen, Department of Prehistory and Quaternary Ecology, Schloss Hohentübingen, 72070 Tübingen, Germany ; Eberhard Karls Universität Tübingen = University of Tübingen | Agroécologie [Dijon] ; Université de Bourgogne (UB)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Dijon ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | This study was financially supported by the German ResearchFoundation (DFG) under the Collaborative Research Center 1253CAMPOS (DFG grant SFB 1253/1 2017).
13C assimilation as well as functional gene abundance and expression elucidate the biodegradation of glyphosate in a field experiment Full text
2022
Wirsching, Johannes | Wimmer, Benedikt | Ditterich, Franziska | Schlögl, Johanna | Martin-Laurent, Fabrice | Huhn,, Carolin | Haderlein, Stefan, B. | Kandeler, Ellen | Poll, Christian | University of Stuttgart, Germany | Eberhard Karls University of Tübingen, Department of Prehistory and Quaternary Ecology, Schloss Hohentübingen, 72070 Tübingen, Germany ; Eberhard Karls Universität Tübingen = University of Tübingen | Agroécologie [Dijon] ; Université de Bourgogne (UB)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Dijon ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | This study was financially supported by the German ResearchFoundation (DFG) under the Collaborative Research Center 1253CAMPOS (DFG grant SFB 1253/1 2017).
International audience | Glyphosate (N-phosphonomethylglycine; GLP) and its main metabolite AMPA (aminomethylphosphonic acid), are frequently detected in relatively high concentrations in European agricultural topsoils. Glyphosate has a high sorption affinity, yet it can be detected occasionally in groundwater. We hypothesized that shrinkage cracks occurring after dry periods could facilitate GLP transport to greater depths where subsoil conditions slow further microbial degradation. To test this hypothesis, we simulated a heavy rainfall event (HRE) on a clay-rich arable soil. We applied 2.1 kg ha−1 of 100% 13C3, 15N-labeled GLP one day before the simulated rainfall event. Microbial degradation of translocated GLP over a 21-day period was assessed by quantifying 13C incorporation into phospholipid fatty acids. Microbial degradation potential and activity were determined by quantifying the abundance and expression of functional genes involved in the two known degradation pathways of GLP; to AMPA (goxA) or sarcosine (sarc). We confirmed that goxA transcripts were elevated in the range of 4.23 x 105 copy numbers g−1 soil only one day after application. The increase in AMPA associated with a rise in goxA transcripts and goxA-harboring microorganisms indicated that the degradation pathway to AMPA dominated. Based on 13C-enrichment 3 h after the HRE, fungi appeared to initiate glyphosate degradation. At later time points, Gram+-bacteria proved to be the main degraders due to their higher 13C-incorporation. Once GLP reached the subsoil, degradation continued but more slowly. By comparing GLP distribution and its microbial degradation in macropores and in the bulk soil, we demonstrated different time- and depth-dependent GLP degradation dynamics in macropores. This indicates the need for field studies in which soil properties relevant to GLP degradation are related to limiting environmental conditions, providing a realistic assessment of GLP fate in soils.
Show more [+] Less [-]13C assimilation as well as functional gene abundance and expression elucidate the biodegradation of glyphosate in a field experiment Full text
2022
Wirsching, Johannes | Wimmer, Benedikt | Ditterich, Franziska | Schlögl, Johanna | Martin-Laurent, Fabrice | Huhn, Carolin | Haderlein, Stefan | Kandeler, Ellen | Poll, Christian
Glyphosate (N-phosphonomethylglycine; GLP) and its main metabolite AMPA (aminomethylphosphonic acid), are frequently detected in relatively high concentrations in European agricultural topsoils. Glyphosate has a high sorption affinity, yet it can be detected occasionally in groundwater. We hypothesized that shrinkage cracks occurring after dry periods could facilitate GLP transport to greater depths where subsoil conditions slow further microbial degradation. To test this hypothesis, we simulated a heavy rainfall event (HRE) on a clay-rich arable soil. We applied 2.1 kg ha⁻¹ of 100% ¹³C₃, ¹⁵N-labeled GLP one day before the simulated rainfall event. Microbial degradation of translocated GLP over a 21-day period was assessed by quantifying ¹³C incorporation into phospholipid fatty acids. Microbial degradation potential and activity were determined by quantifying the abundance and expression of functional genes involved in the two known degradation pathways of GLP; to AMPA (goxA) or sarcosine (sarc). We confirmed that goxA transcripts were elevated in the range of 4.23 x 10⁵ copy numbers g⁻¹ soil only one day after application. The increase in AMPA associated with a rise in goxA transcripts and goxA-harboring microorganisms indicated that the degradation pathway to AMPA dominated. Based on ¹³C-enrichment 3 h after the HRE, fungi appeared to initiate glyphosate degradation. At later time points, Gram⁺-bacteria proved to be the main degraders due to their higher ¹³C-incorporation. Once GLP reached the subsoil, degradation continued but more slowly. By comparing GLP distribution and its microbial degradation in macropores and in the bulk soil, we demonstrated different time- and depth-dependent GLP degradation dynamics in macropores. This indicates the need for field studies in which soil properties relevant to GLP degradation are related to limiting environmental conditions, providing a realistic assessment of GLP fate in soils.
Show more [+] Less [-]Drivers of litter ingestion by sea turtles: three decades of empirical data collected in Atlantic Europe and the Mediterranean Full text
2022
Darmon, Gaëlle | Schulz, Marcus | Matiddi, Marco | Loza, Ana Liria | Tomás, Jesús | Camedda, Andrea | Chaieb, Olfa | El Hili, Hedia | Bradai, Mohamed | Bray, Laura | Claro, Françoise | Dellinger, Thomas | Dell'Amico, Florence | de Lucia, Giuseppe | Duncan, Emily | Gambaiani, Delphine | Godley, Brendan | Kaberi, Helen | Kaska, Yakup | Martin, Jessica | Moreira, Cláudia | Ostiategui, Patricia | Pham, Christopher | Piermarini, Raffaella | Revuelta, Ohiana | Rodríguez, Yasmina | Silvestri, Cecilia | Snape, Robin | Sozbilen, Dogăn | Tsangaris, Catherine | Vale, Maria | Vandeperre, Frederic | Miaud, Claude | Centre d’Ecologie Fonctionnelle et Evolutive (CEFE) ; Université Paul-Valéry - Montpellier 3 (UPVM)-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)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM) | Patrimoine naturel (PatriNat) ; Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-OFB Direction surveillance, évaluation,données (OFB - DSUED) ; Office français de la biodiversité (OFB)-Office français de la biodiversité (OFB)
International audience | Sea turtles are considered as bio-indicators for monitoring the efficiency of restoration measures to reduce marine litter impacts on health. However, the lack of extended and standardised empirical data has prevented the accurate analysis of the factors influencing litter ingestion and the relationships with individual health. Historic data collected from 1988 and standard data collected from 2016 were harmonised to enable such analyses on necropsied loggerhead turtles (Caretta caretta) in eight Mediterranean and North-East Atlantic countries. Litter was found in 69.24 % of the 1121 individuals, mostly single-use and fishing-related plastics. Spatial location, sex and life history stage explained a minor part of litter ingestion. While no relationships with health could be detected, indicating that all individuals can be integrated as bio-indicators, the mechanistic models published in literature suggest that the high proportion of plastics in the digestive contents (38.77 % per individual) could have long-term repercussions on population dynamics.
Show more [+] Less [-]LCA of wet-weather emissions of an urban wastewater system: the case of the Greater Paris watershed Full text
2017
Risch, Eva | Gasperi, Johnny | Gromaire, Marie-Christine | Chebbo, Ghassan | Azimi, Sam | Rocher, Vincent | Roux, Philippe, | Rosenbaum, R.K. | Sinfort, Carole, | Pôle ELSA, Environmental Life Cycle and Sustainability Assessment (ELSA) | Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Laboratoire Eau Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-École des Ponts ParisTech (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12) | SIAAP - Direction du Développement et de la Prospective ; SIAAP
International audience
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