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Bernard Clément - One of the best experts on this subject based on the ideXlab platform.

  • Water-level fluctuation enhances sediment and trace metal Mobility in lake littoral.
    Chemosphere, 2020
    Co-Authors: Nathalie Lécrivain, Bernard Clément, Aymeric Dabrin, Juliette Seigle-ferrand, Damien Bouffard, Emmanuel Naffrechoux, Victor Frossard
    Abstract:

    Abstract Water-level fluctuation (WLF) is a widespread management action in lakes and reservoirs whose impacts on Contaminant fate have seldom been investigated. We used near shore hourly measurements (n = 2122) of turbidity (Contaminant proxy) and water velocity (sediment resuspension proxy) to track high-frequency Contaminant dynamics during a 0.6 m change in water level observed in autumn 2017 in a large French lake. Simultaneously, discrete trace metal measurements highlighted that trapped sediment was more contaminated and finer than surficial sediment supporting that suspended particles (measured by turbidity) were a preferential medium for Contaminant Mobility. General additive models involving tensor products revealed the enhancement of wind-speed and river discharge effects on turbidity with water draw down. The decrease of the explained deviances by the models over time-lags indicated short time-scale response of turbidity to external forcing. Three of the four major turbid events occurred at the lowest water-level and were concomitant of sediment resuspension as well as precipitation events and/or river flood suggesting a complex interplay among in-lake and watershed processes at controlling sediment Mobility during the WLF. These results shed in light that WLF can affect lake littoral hydrodynamic cascading up to the enhancement of Contaminant Mobility. Sediment resuspension may be an overlooked feature of WLF increasing contamination risk and exposure for littoral organisms with widespread ecological consequences due to the large number of water-level regulated ecosystems.

  • Changes in Mobility of trace metals at the sediment-water-biota interfaces following laboratory drying and reimmersion of a lacustrine sediment.
    Environmental science and pollution research international, 2019
    Co-Authors: Nathalie Lécrivain, Victor Frossard, Bernard Clément
    Abstract:

    Alterations in the timing, frequency, and magnitude of water level fluctuations (WLF) in lakes may result in important changes in abiotic parameters that can affect sediment-borne Contaminant Mobility at the sediment-water-biota interfaces in littoral zones. This study aims to assess the Mobility of trace metals (TMs)—Cd, Cr, Cu, Ni, Pb, and Zn—under laboratory-simulated WLF (i.e., drying and reimmersion of sediments) through a three-pronged approach. One surficial sediment was sampled from the shoreline of a large French lake exhibiting an artificially limited WLF. A sample was enriched with a solution of TMs to ensure significant measurements of Mobility. The spiked and naturally contaminated sediments were dried and reimmersed. The first approach consisted in measuring the Mobility of TMs from the sediment to the water column under resuspensions of particles through leaching tests. The second approach assessed the partitioning of TMs between the different binding forms within the sediments through sequential extraction tests. The last approach tested the changes in TM bioconcentration in organisms exposed to sediment through microcosm assays. The hypothesis was that WLF may increase Mobility from the sediment to the water column relative to Mobility from the residual to easily mobilizable fractions within the sediments and consequently increase the bioconcentration of less inert trace metals, mostly Cd and Zn. This hypothesis was partly rejected as TM binding forms mainly increased toward the residual fractions within the sediment, especially for Cd and Zn, and bioconcentration mainly decreased following WLF. However, TM concentration increased in the water column when WLF included great resuspension of particles. The study also provides insights into the complex relationships among Contaminant Mobility to the water column, bioavailability, and bioconcentration, especially in the context of large abiotic disturbances such as WLF. These findings may be useful for further management strategies for WLF-regulated lakes and reservoirs.

Victor Frossard - One of the best experts on this subject based on the ideXlab platform.

  • Water-level fluctuation enhances sediment and trace metal Mobility in lake littoral.
    Chemosphere, 2020
    Co-Authors: Nathalie Lécrivain, Bernard Clément, Aymeric Dabrin, Juliette Seigle-ferrand, Damien Bouffard, Emmanuel Naffrechoux, Victor Frossard
    Abstract:

    Abstract Water-level fluctuation (WLF) is a widespread management action in lakes and reservoirs whose impacts on Contaminant fate have seldom been investigated. We used near shore hourly measurements (n = 2122) of turbidity (Contaminant proxy) and water velocity (sediment resuspension proxy) to track high-frequency Contaminant dynamics during a 0.6 m change in water level observed in autumn 2017 in a large French lake. Simultaneously, discrete trace metal measurements highlighted that trapped sediment was more contaminated and finer than surficial sediment supporting that suspended particles (measured by turbidity) were a preferential medium for Contaminant Mobility. General additive models involving tensor products revealed the enhancement of wind-speed and river discharge effects on turbidity with water draw down. The decrease of the explained deviances by the models over time-lags indicated short time-scale response of turbidity to external forcing. Three of the four major turbid events occurred at the lowest water-level and were concomitant of sediment resuspension as well as precipitation events and/or river flood suggesting a complex interplay among in-lake and watershed processes at controlling sediment Mobility during the WLF. These results shed in light that WLF can affect lake littoral hydrodynamic cascading up to the enhancement of Contaminant Mobility. Sediment resuspension may be an overlooked feature of WLF increasing contamination risk and exposure for littoral organisms with widespread ecological consequences due to the large number of water-level regulated ecosystems.

  • Changes in Mobility of trace metals at the sediment-water-biota interfaces following laboratory drying and reimmersion of a lacustrine sediment.
    Environmental science and pollution research international, 2019
    Co-Authors: Nathalie Lécrivain, Victor Frossard, Bernard Clément
    Abstract:

    Alterations in the timing, frequency, and magnitude of water level fluctuations (WLF) in lakes may result in important changes in abiotic parameters that can affect sediment-borne Contaminant Mobility at the sediment-water-biota interfaces in littoral zones. This study aims to assess the Mobility of trace metals (TMs)—Cd, Cr, Cu, Ni, Pb, and Zn—under laboratory-simulated WLF (i.e., drying and reimmersion of sediments) through a three-pronged approach. One surficial sediment was sampled from the shoreline of a large French lake exhibiting an artificially limited WLF. A sample was enriched with a solution of TMs to ensure significant measurements of Mobility. The spiked and naturally contaminated sediments were dried and reimmersed. The first approach consisted in measuring the Mobility of TMs from the sediment to the water column under resuspensions of particles through leaching tests. The second approach assessed the partitioning of TMs between the different binding forms within the sediments through sequential extraction tests. The last approach tested the changes in TM bioconcentration in organisms exposed to sediment through microcosm assays. The hypothesis was that WLF may increase Mobility from the sediment to the water column relative to Mobility from the residual to easily mobilizable fractions within the sediments and consequently increase the bioconcentration of less inert trace metals, mostly Cd and Zn. This hypothesis was partly rejected as TM binding forms mainly increased toward the residual fractions within the sediment, especially for Cd and Zn, and bioconcentration mainly decreased following WLF. However, TM concentration increased in the water column when WLF included great resuspension of particles. The study also provides insights into the complex relationships among Contaminant Mobility to the water column, bioavailability, and bioconcentration, especially in the context of large abiotic disturbances such as WLF. These findings may be useful for further management strategies for WLF-regulated lakes and reservoirs.

Nathalie Lécrivain - One of the best experts on this subject based on the ideXlab platform.

  • Water-level fluctuation enhances sediment and trace metal Mobility in lake littoral.
    Chemosphere, 2020
    Co-Authors: Nathalie Lécrivain, Bernard Clément, Aymeric Dabrin, Juliette Seigle-ferrand, Damien Bouffard, Emmanuel Naffrechoux, Victor Frossard
    Abstract:

    Abstract Water-level fluctuation (WLF) is a widespread management action in lakes and reservoirs whose impacts on Contaminant fate have seldom been investigated. We used near shore hourly measurements (n = 2122) of turbidity (Contaminant proxy) and water velocity (sediment resuspension proxy) to track high-frequency Contaminant dynamics during a 0.6 m change in water level observed in autumn 2017 in a large French lake. Simultaneously, discrete trace metal measurements highlighted that trapped sediment was more contaminated and finer than surficial sediment supporting that suspended particles (measured by turbidity) were a preferential medium for Contaminant Mobility. General additive models involving tensor products revealed the enhancement of wind-speed and river discharge effects on turbidity with water draw down. The decrease of the explained deviances by the models over time-lags indicated short time-scale response of turbidity to external forcing. Three of the four major turbid events occurred at the lowest water-level and were concomitant of sediment resuspension as well as precipitation events and/or river flood suggesting a complex interplay among in-lake and watershed processes at controlling sediment Mobility during the WLF. These results shed in light that WLF can affect lake littoral hydrodynamic cascading up to the enhancement of Contaminant Mobility. Sediment resuspension may be an overlooked feature of WLF increasing contamination risk and exposure for littoral organisms with widespread ecological consequences due to the large number of water-level regulated ecosystems.

  • Changes in Mobility of trace metals at the sediment-water-biota interfaces following laboratory drying and reimmersion of a lacustrine sediment.
    Environmental science and pollution research international, 2019
    Co-Authors: Nathalie Lécrivain, Victor Frossard, Bernard Clément
    Abstract:

    Alterations in the timing, frequency, and magnitude of water level fluctuations (WLF) in lakes may result in important changes in abiotic parameters that can affect sediment-borne Contaminant Mobility at the sediment-water-biota interfaces in littoral zones. This study aims to assess the Mobility of trace metals (TMs)—Cd, Cr, Cu, Ni, Pb, and Zn—under laboratory-simulated WLF (i.e., drying and reimmersion of sediments) through a three-pronged approach. One surficial sediment was sampled from the shoreline of a large French lake exhibiting an artificially limited WLF. A sample was enriched with a solution of TMs to ensure significant measurements of Mobility. The spiked and naturally contaminated sediments were dried and reimmersed. The first approach consisted in measuring the Mobility of TMs from the sediment to the water column under resuspensions of particles through leaching tests. The second approach assessed the partitioning of TMs between the different binding forms within the sediments through sequential extraction tests. The last approach tested the changes in TM bioconcentration in organisms exposed to sediment through microcosm assays. The hypothesis was that WLF may increase Mobility from the sediment to the water column relative to Mobility from the residual to easily mobilizable fractions within the sediments and consequently increase the bioconcentration of less inert trace metals, mostly Cd and Zn. This hypothesis was partly rejected as TM binding forms mainly increased toward the residual fractions within the sediment, especially for Cd and Zn, and bioconcentration mainly decreased following WLF. However, TM concentration increased in the water column when WLF included great resuspension of particles. The study also provides insights into the complex relationships among Contaminant Mobility to the water column, bioavailability, and bioconcentration, especially in the context of large abiotic disturbances such as WLF. These findings may be useful for further management strategies for WLF-regulated lakes and reservoirs.

Nicolas Fatin-rouge - One of the best experts on this subject based on the ideXlab platform.

  • Assessing natural clays of a contaminated site to stabilize and reduce the ecotoxicity of a coal tar.
    Ecotoxicology and environmental safety, 2019
    Co-Authors: Rachida Bamze Attoumani, Annette De Vaufleury, Nadia Crini, Nicolas Fatin-rouge
    Abstract:

    Stabilization/solidification is widely used for the immobilization of pollutants in matrices. This work addresses the effect of illite amendment to a liquid coal tar on organic compounds (OCs) immobilization, especially PAHs and BTEX. For practical purpose, illite was selected as raw clay material available on the coal tar contaminated site. Contaminants availability and ecotoxicity of clay/tar matrices at various ratios and considering several treatments were assessed. Varying the tar mass fraction from 1 to 0.12, strongly viscous pastes, pellets and powders were obtained successively, with minimal Contaminant Mobility observed for tar fractions ranging from 0.28 to 0.80. Pellets obtained for the tar fraction of 0.33 were particularly studied for toxicity tests, because of their ease of handling. Using the land snail Cantareus aspersus as an ecotoxicity probe, mechanisms of PAHs bioavailability considering several treatments were studied. Considering either land snails for direct contact or exposed to vapors, or Lymnaea stagnalis for contact with leachates, toxicity of matrices decreased with ageing or even better with incineration.

John R. Lawrence - One of the best experts on this subject based on the ideXlab platform.

  • Microbial interactions with naturally occurring hydrophobic sediments: Influence on sediment and associated Contaminant Mobility
    Water research, 2016
    Co-Authors: Ian G. Droppo, Bommanna G. Krishnappan, John R. Lawrence
    Abstract:

    The erosion, transport and fate of sediments and associated Contaminants are known to be influenced by both particle characteristics and the flow dynamics imparted onto the sediment. The influential role of bitumen containing hydrophobic sediments and the microbial community on sediment dynamics are however less understood. This study links an experimental evaluation of sediment erosion with measured sediment-associated Contaminant concentrations and microbial community analysis to provide an estimate of the potential for sediment to control the erosion, transport and fate of Contaminants. Specifically the paper addresses the unique behaviour of hydrophobic sediments and the role that the microbial community associated with hydrophobic sediment may play in the transport of contaminated sediment. Results demonstrate that the hydrophobic cohesive sediment demonstrates unique transport and particle characteristics (poor settling and small floc size). Biofilms were observed to increase with consolidation/biostabilization times and generated a unique microbial consortium relative to the eroded flocs. Natural oil associated with the flocs appeared to be preferentially associated with microbial derived extracellular polymeric substances. While PAHs and naphthenic acid increased with increasing shear (indicative of increasing loads), they tended to decrease with consolidation/biostabilization (CB) time at similar shears suggesting a chemical and/or biological degradation. PAH and napthenic acid degrading microbes decreased with time as well, which may suggest that there was a reduced pool of PAHs and naphthenic acids available resulting in their die off. This study emphasizes the importance that any management strategies and operational assessments for the protection of human and aquatic health incorporate the sediment (suspended and bed sediment) and biological (biofilm) compartments and the energy dynamics within the system in order to better predict Contaminant transport.