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Long term survey of heavy metal pollution, biofilm contamination and diatom community structure in the Riou-Mort watershed, South West France | Pollution des eaux par les métaux lourds, contamination du biofilm et effets sur la structure des communautés de diatomées : Suivi long terme du bassin versant du Riou-Mort, SO France
2008
Morin, Soizic | Duong, T.T. | Dabrin, A. | Coynel, A. | Herlory, O. | Baudrimont, M. | Delmas, François | Durrieu, G. | Schäfer, J. | Winterton, P. | Blanc, G. | Coste, Michel | Réseaux épuration et qualité des eaux (UR REBX) ; Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF) | 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) | Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)
[Departement_IRSTEA]MA [TR1_IRSTEA]QSA / DYNAQ | International audience | In a metal-polluted stream in the Riou Mort watershed in SW France, periphytic biofilm was analyzed for diatom cell densities and taxonomic composition, dry weight and metal bio-accumulation (cadmium and zinc). Periphytic diatom communities were affected by the metal but displayed induced tolerance, seen through structural impact (dominance of small, adnate species) as well as morphological abnormalities particularly in the genera Ulnaria and Fragilaria. Species assemblages were characterized by taxa known to occur in metal-polluted environments, and shifts in the community structure expressed seasonal patterns: high numbers of Eolimna minima, Nitzschia palea and Pinnularia parvulissima were recorded in Summer and Autumn, whereas the species Surirella brebissonii, Achnanthidium minutissimum, Navicula lanceolata and Surirella angusta were dominant in Winter and Spring. Commonly used indices such as the Shannon diversity index and Specific Pollution Sensitivity Index reflected the level of pollution and suggest seasonal periodicity, the lowest diversities being observed in Summer.
Show more [+] Less [-]Effect of vegetation type on throughfall deposition and seepage flux.
2008
de Schrijver, A. | Staelens, J. | Wuyts, K. | van Hoydonck, G. | Janssen, N. | Mertens, J. | Gielis, L. | Geudens, G. | Augusto, Laurent | Verheyen, Kris | Laboratory of Forestry ; Universiteit Gent = Ghent University (UGENT) | Haskoning Belgium BVBA ; Partenaires INRAE | Natuurpunt | Transfert Sol-Plante et Cycle des Eléments Minéraux dans les Ecosystèmes Cultivés (TCEM) ; Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)
International audience | This paper compares different vegetation types (coniferous and deciduous forest, grassed and pure heathland) in terms of input (throughfall deposition) and output (seepage flux) in a region with intermediate nitrogen load (+/-20 kg N ha(-1) y(-1) via bulk precipitation) in comparable conditions in north Belgium. Coniferous forest (two plots Pinus sylvestris and two plots Pinus nigra) received significantly higher nitrogen and sulphur throughfall deposition than deciduous forest and heathland. Grassed and pure heathland had significantly highest throughfall quantities of Ca2+ and Mg2+, respectively. The observed differences in throughfall deposition between the different vegetation types were not univocally reflected in the ion seepage flux. Considerable seepage fluxes of NO3-, SO42-, Ca2+ and Al(III) were only found under the P. nigra plots. We discuss our hypothesis that the P. nigra forests already evolved to a situation of N saturation, while the other vegetation types did not. (C) 2007 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Long-term effects of aided phytostabilisation of trace elements on microbial biomass and activity, enzyme activities, and composition of microbial community in the Jales contaminated mine spoils
2008
Renella, Giancarlo | Landi, Loretta | Ascher, Judith | Ceccherini, Maria Teresa | Pietramellara, Giacomo | Mench, Michel | Nannipieri, Paolo | Università degli Studi di Firenze = University of Florence = Université de Florence (UniFI) | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)
International audience | We studied the effectiveness of remediation on microbial endpoints, namely microbial biomass and activity, microbial and plant species richness, of an As-contaminated mine spoil, amended with compost (C) alone and in combination with beringite (B) or zerovalent iron grit (Z), to increase organic matter content and reduce trace elements mobility, and to allow Holcus lanatus and Pinus pinaster growth. Untreated spoil showed the lowest microbial biomass and activity and hydrolase activities, and H. lanatus as sole plant species, whereas the presented aided phytostabilisation option, especially CBZ treatment, significantly increased microbial biomass and activity and allowed colonisation by several plant species, comparable to those of an uncontaminated sandy soil. Microbial species richness was only increased in spoils amended with C alone. No clear correlation occurred between trace element mobility and microbial parameters and plant species richness. Our results indicate that the choice of indicators of soil remediation practices is a bottleneck. Organo-mineral amendment and revegetation of a gold mine spoil increased microbial activity but did not increase microbial species richness.
Show more [+] Less [-]Remediation of copper-contaminated topsoils from a wood treatment facility using in situ stabilisation
2008
Bes, Clémence | Mench, Michel | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)
International audience | Five organic matters, three phosphate compounds, zerovalent iron grit (ZVIG, 2% by soil weight), two alkaline compounds, and two commercial formulations were incorporated, singly and some combined with ZVIG, into a highly Cu-contaminated topsoil (Soil P7, 2600 mg Cu kg−1) from a wood treatment facility. Formulations and two composts were also singly incorporated into a slightly Cu-contaminated topsoil (Soil P10, 118 mg Cu kg−1) from the facility surrounding. This aimed to reduce the labile pool of Cu and its accumulation in beans cultivated on potted soils in a climatic chamber. Lowest Cu concentration in soil solution occurred in P7 soils amended with activated carbon (5%) and ZVIG, singly and combined. Basic slag (3.9%) and compost of sewage sludge (5%) combined with ZVIG promoted shoot production and limited foliar Cu accumulation. For amended P10 soils, no changes occurred in soil solution and foliar Cu concentrations, but one compost increased shoot production. Three soil amendments, iron grit with compost, calcium oxide, and basic slags, decreased the phytotoxicity of a Cu-contaminated soil.
Show more [+] Less [-]Influence of organic amendments on diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters.
2008
Thevenot, Mathieu | Dousset, Sylvie | Rousseaux, S. | Andreux, Francis | Microbiologie du Sol et de l'Environnement (MSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB) | Biogéosciences [UMR 6282] (BGS) ; Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Recherche en Vigne et Vin (REVV) ; Université de Bourgogne (UB) | PhD grant from the Ministère de l'Education Nationale, de la Recherche et de la Technologie.
9 pages | International audience | The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron þ metabolites) in the leachates of the VR soil (0.19e0.71%) was lower than in the Bj soil (4.27e8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence diuron leaching.
Show more [+] Less [-]Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France
2008
Banas, Damien | Masson, Gérard | Leglize, L. | Usseglio-Polatera, Philippe | Boyd, C.E. | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Université Paris-Sud - Paris 11 (UP11) | Centre National de la Recherche Scientifique (CNRS) | AgroParisTech | Université Paul Verlaine - Metz (UPVM) | Auburn University (AU)
International audience | Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2–620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L. Effluent phosphorus loads were higher than those reported for more intensive aquaculture ponds, but the pollutant source was catchments rather than feeds and fertilizers.
Show more [+] Less [-]Influence of organic amendments on diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters.
2008
Thevenot, Mathieu | Dousset, Sylvie | Rousseaux, S. | Andreux, Francis | Microbiologie du Sol et de l'Environnement (MSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB) | Biogéosciences [UMR 6282] (BGS) ; Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Recherche en Vigne et Vin (REVV) ; Université de Bourgogne (UB) | PhD grant from the Ministère de l'Education Nationale, de la Recherche et de la Technologie.
9 pages | International audience | The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron þ metabolites) in the leachates of the VR soil (0.19e0.71%) was lower than in the Bj soil (4.27e8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence diuron leaching.
Show more [+] Less [-]Temperature and water pressure head effects on the degradation of the diketonitrile metabolite of isoxaflutole in a loamy soil under two tillage systems
2008
Alletto, Lionel | Benoit, Pierre | Bergheaud, Valerie | Coquet, Yves | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Ecole supérieure d'agriculture de Purpan (ESAP) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)
Laboratory studies were conducted to evaluate the effects of temperature and water pressure head on the degradation of the diketonitrile metabolite (DKN) of isoxaflutole during 84 d in samples collected in a loamy soil under conventional (CT) and conservation (MT) tillage systems. Soil temperature was the major factor controlling DKN degradation in the two tillage systems. The shortest half-lives (T1/2) were measured in the seedbed samples under MT at 25 °C and -33 cm water pressure head. We found that mouldboard ploughing under CT was responsible for the spatial variability of herbicide degradation properties, whereas under MT herbicide degradation was associated to the vertical distribution of organic matter. Tillage practices influence the spatial variability of diketonitrile degradation in soil and its sensitivity to pedoclimatic conditions.
Show more [+] Less [-]Relationship between ammonia stomatal compensation point and nitrogen metabolism in arable crops: Current status of knowledge and potential modelling approaches
2008
Massad, Raia Silvia | Loubet, Benjamin | Tuzet, Andree | Cellier, Pierre | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech
The ammonia stomatal compensation point of plants is determined by leaf temperature, ammonium concentration ([NH4+]apo) and pH of the apoplastic solution. The later two depend on the adjacent cells metabolism and on leaf inputs and outputs through the xylem and phloem. Until now only empirical models have been designed to model the ammonia stomatal compensation point, except the model of Riedo et al. (2002. Coupling soil-plant-atmosphere exchange of ammonia with ecosystem functioning in grasslands. Ecological Modelling 158, 83e110), which represents the exchanges between the plant’s nitrogen pools. The first step to model the ammonia stomatal compensation point is to adequately model [NH4+]apo. This [NH4+]apo has been studied experimentally, but there are currently no process-based quantitative models describing its relation to plant metabolism and environmental conditions. This study summarizes the processes involved in determining the ammonia stomatal compensation point at the leaf scale and qualitatively evaluates the ability of existing whole plant N and C models to include a model for [NH4+]apo.
Show more [+] Less [-]Ozone risk assessment for plants: central role of metabolism-dependent changes in reducing power
2008
Dizengremel, Pierre, P. | Le Thiec, Didier | Bagard, Mathieu | Jolivet, Yves, Y. | Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
International audience | The combination of stomatal-dependent ozone flux and total ascorbate level is currently presented as a correct indicator for determining the degree of sensitivity of plants to ozone. However, the large changes in carbon metabolism could play a central role in the strategy of the foliar cells in response to chronic ozone exposure, participating in the supply of reducing power and carbon skeletons for repair and detoxification, and modifying the stomatal mode of functioning. To reinforce the accuracy of the definition of the threshold for ozone risk assessment, it is proposed to also consider the redox pool (NAD(P)H), the ratio between carboxylases and the water use efficiency as indicators of the differential ozone tolerance of plants.
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