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Anthropogenic lead distribution in soils under arable land and permanent grassland estimated by Pb isotopic compositions Texte intégral
2008
Fernandez, Christelle | Monna, Fabrice | Labanowski, Jérôme | Loubet, Michel | van Oort, Folkert, F. | Unité de recherche Science du Sol (USS) ; Institut National de la Recherche Agronomique (INRA) | Centre des Sciences de la Terre ; Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon | Laboratoire de chimie et microbiologie de l'eau [UMR 6008] (LCME [Poitiers]) ; Université de Poitiers = University of Poitiers (UP)-Institut de Chimie - CNRS Chimie (INC-CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Géochimie ; Université Toulouse - Jean Jaurès (UT2J) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)
International audience | The role of land use on fate of metals in soils is poorly understood. In this work, we studied the incorporation of lead in two neighboring soils with comparable pedogenesis but under long-term different agricultural management. Distributions of anthropogenic Pb were assessed from concentrations and isotopic compositions determined on bulk horizon samples, systematical 5–10 cm increment samples, and on 24-h EDTA extracts. Minor amounts of anthropogenic lead were detected until 1-m depth under permanent grassland, linked to high earthworm activity. In arable land, exogenous Pb predominantly accumulated at depths <60 cm. Although the proximity between the two sites ensured comparable exposition regarding atmospheric Pb deposition, the isotopic compositions clearly showed the influence of an unidentified component for the cultivated soil. This work highlights the need for exhaustive information on historical human activities in such anthropized agrosystems when fate of metal pollution is considered.
Afficher plus [+] Moins [-]Influence of the media granular size of small pilot subsurface flow wetlands on axial dispersion and the hydraulic behaviour Texte intégral
2008
Fonder, N. | Xanthoulis, Dimitri
peer reviewed | The objective of this paper is to evaluate using tracer tests, the role of the granular media size on the hydraulic behaviour of small -scale pilot horizontal subsurface flow (HSSF) gravel beds. The non-ideal flow was modelled by the tank-in-series model (TIS) using the moment analysis and Gamma distribution fitting using the Solver™ routine in Microsoft Excel™; the Plug Flow with Dispersion (PFD) model was also assessed. Tests were performed under a greenhouse in four identical pilot-scale gravel beds of 9:1:1 ratio, which received an equal, inflow of clear water. The influent flow rate was 40 L/day and the surface area of the pilot cells was 0.8 m². The pea gravel media used in the four beds were as follows: 3-5 mm, 6-8 mm, 8-10 mm and 10-12 mm. The tracer used was Potassium Bromide (KBr) with a concentration of 1 g Br/L, using a single-shot injection into the inlet distribution tubes. Tests were repeated three times, with identical materials and methods. Statistical differences were observed between replications. Water loss by evaporation of the unplanted gravel beds was of 11% for the smaller media size (3-5 mm) which is significantly different than the 4 to 5% obtained for the other media sizes. Tracer detention time, tracer peak time, volumetric and hydraulic efficiencies show all the same tendency which is a significant reduction with larger particles sizes. The two methods of calculation for the number NTIS by moment analysis and Gamma distribution fitting (using Solver™) are significantly different. The Gamma model increases the number of TIS with significantly higher values for smaller media sizes.
Afficher plus [+] Moins [-]Greening Through Industrial Relocation in Vietnam: The Case of Ho Chi Minh City
2008
Le Van Khoa | Ho, P.P.S.
Poly-aromatic hydrocarbon (PAH) inputs from the Rhône River to the Mediterranean Sea in relation with the hydrological cycle: Impact of floods | Influence du cycle hydrologique et des crues sur les apports en hydrocarbure HAP du Rhône à la Méditerranée Texte intégral
2008
Sicre, Marie-Alexandrine | Fernandes, M.B. | Pont, Didier | Paléocéanographie (PALEOCEAN) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-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)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-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) | AQUATIC SCIENCES CENTRE AUS ; 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) | Hydrobiologie (UR HYAX) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF)
[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / HYDRECO | International audience | The concentrations of dissolved and particulate polycyclic aromatic hydrocarbons (PAHs) were monitored in waters of the Rhône River (France) every fortnight for a full calendar year, from June 1994 to May 1995. All flood events occurring over the course of the experiment were sampled at higher frequency to better quantify the impact of these extreme hydrological episodes on the annual export of PAHs to the Mediterranean Sea. This time-series indicates that more than 90% of the annual load of particulate PAHs is transported during flood episodes, with 77% discharged during the course of only one extreme flood event occurring in November 1994. During these intense events, riverine particles are depleted in PAHs while at low river discharge particles are PAH-enriched. Dissolved PAHs were less variable and less abundant than adsorbed PAHs, consistently with the low solubility of these compounds.
Afficher plus [+] Moins [-]The "storm of the century" (December 1999) and the accidental escape of Siberian sturgeons (Acipenser baerii) into the Gironde estuary (Southwest France): an original approach for metal contamination | La "tempête du siècle" (decembre 1999) et l'échappement accidentel d'esturgeons sibériens (Acipenser baerii) dans l'estuaire de la Gironde (SO france) : un bioindicateur original de contamination métallique Texte intégral
2008
Maury-Brachet, Régine | Rochard, Eric | Durrieu, Gilles | Boudou, Alain | 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) | Ecosystèmes estuariens et poissons migrateurs amphihalins (UR EPBX) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | Université de Bordeaux (UB)
[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / DYMECO | International audience | Goal, Scope and Background. The Gironde estuary is considered as a reference ecosystem with a large fish assemblage (75 species) and the presence of eleven diadromous species. However, geochemical studies and biomonitoring using oysters have shown high metal pollution levels. During the December 1999 hurricane, more than 5,000 young Siberian sturgeons (Acipenser baerii) accidentally escaped from a fish farm into the estuary, where this species had not been present until then. Methods. In 2002/2003, thirteen sturgeons were collected from the estuary and twelve were obtained from the fish farm, from the same initial batch. Analysis of five metals (cadmium, zinc, copper, lead, mercury) measured in the gills, muscle, liver and kidneys, revealed significantly higher levels of cadmium, lead and mercury in the sturgeon collected from the estuary compared with those from the fish farm. Results and Discussion. Metal analysis of the stomach contents of fish collected from the estuary and artificial food used in the fish farm indicated that dietary exposure might account for the differences observed. Nevertheless, metal concentrations in sturgeons that had spent about three years in the Gironde estuary may be considered low when compared with other species (mullets, eels) or with data in the literature regarding concentrations able to induce structural and functional perturbations in fish. As the introduced Siberian sturgeons live in the same place and feed on the same prey as the juveniles of the endangered A. sturio, our results indicate in the short term that this strictly protected species does not appear to be much affected by the polymetallic pollution in the Gironde estuary. Marked differences in the concentrations of three metals (Cd, Pb, Hg) were established in four organs (gills, liver, skeletal muscle, kidneys) of Siberian sturgeons between specimens that had accidentally escaped into the Gironde estuary (France) during the December 1999 hurricane and were collected in March/June 2003 and specimens from the same initial batch at the fish farm. Recommendations and Perspectives. Based on these results, a programme will be set up, with sampling campaigns carried out in the estuary every two years, with systematic monitoring of age in order to check the origin of individuals, in conjunction with sampling of sturgeon from the fish farm. This programme will complement other studies on several biological species representative of the main trophic levels in the estuary, especially the plankton component, benthic macroinvertebrates and oysters.
Afficher plus [+] Moins [-]Effects of an oral subacute administration of benzo(a)Pyrene on cerebral CYP1A1 expression and anxiety-related behaviour in adult mice Texte intégral
2008
Cao, Lingxue | Grova, N. | Muller, C.P. | Schroeder, Henri | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Centre de Recherche Public - Gabriel Lippmann (LUXEMBOURG)
International audience
Afficher plus [+] Moins [-]Neurobehavioural toxicity of a chronic exposure to the airborne polycyclic aromatic hydrocarbon fluorene in adult wistar male rats: a preliminary study about the effects of a 28 day administration using the intraperitoneal or the oral way Texte intégral
2008
Rychen, Guido | Schroeder, Henri | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
International audience
Afficher plus [+] Moins [-]Brain and behaviour toxicity of airborn pollutants Texte intégral
2008
Schroeder, Henri | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
International audience
Afficher plus [+] Moins [-]Phosphorus removal by apatite in horizontal flow constructed wetlands: kinetics and treatment reliability Texte intégral
2008
Harouiya, N. | Molle, Pascal | Prost Boucle, S. | Liénard, A.
Phosphorus removal in constructed wetlands have received particular attention last decades by using specific materials promoting adsorption/precipitation mechanisms. Recent studies have shown interest in using apatite materials to promote P precipitation onto the particle surface. As previous trials were mainly done by lab experiments, this present study aims to evaluate the real potential of apatites to remove P from wastewater in pilots and a full-scale plant. Two different apatites have been studied in 1.5 m² pilots fed with wastewater from the outlet of a trickling filter. They were monitored to follow inlet/oulet flows, hydraulic gradient, meteorological conditions, pH, temperature, and redox potential. Treatment performances were evaluated by regular complete analysis (COD, BOD, SS, nitrogen and phosphorus forms, Ca) as well as PO4-P by a WTW online analyser. At the same time a full-scale experiment study have been done to point out P retention properties in real conditions over a 2 years period. P retention kinetics of two qualities of apatites are presented and discussed according to the temperature dependence. In this work apatite appears to have high retention capacity and is still an interesting way for P removal in constructed wetlands. However, other qualities of apatite must be studied for a better reliability of treatment.
Afficher plus [+] Moins [-]Plant, water and milk pollution in Kazakhstan Texte intégral
2008
Diacono, Emilie | Faye, Bernard | Meldebekova, Aliya | Konuspayeva, Gaukhar
Since its independence in 1991, Kazakhstan is in a state of "ecological crises", due to the specific place for nuclear test by soviet government for long time, and to the development of irrigation for field cottons linked with decreasing Aral Sea level. In addition the manufacturing of metals and the minerals had some impact on environmental contamination. In the South of Kazakhstan, eight farms were sampled close to probable pollution sources. Samples of camel milk, fodder and water were collected in each farm and analyzed for copper, iron, manganese, zinc, arsenic and lead. The mean content in fodder of Cu, Fe, Mn, Zn, As and Pb was 10.40 ± 2.93, 793.69 ± 630.48, 62.38 ± 20.67, 32.95 ± 27.15, 1.03 ± 0.49 and 4.28 ± 9.60 ppm respectively. In camel milk mean content of these heavy metals was respectively of 0.07 ± 0.04, 1.48 ± 0.53, 0.08 ± 0.03, 5.16 ± 2.17, <0.1, and 0.025 ± 0.02 ppm respectively. No heavy metals were detected in samples of water with the analytical methods used. The relationships between heavy metals in water, forages and milk were not clear. Some information's are lacking. We need to extend sampling at more areas where camels, cows, goat and sheep farms are closed to pollution areas, and analyzed other heavy metals suspected in pollution process.
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