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2. Kd distributions in freshwater systems as a function of material type, mass-volume ratio, dissolved organic carbon and pH

Author

Mohamed Krimissa, Wirginia Tomczak, Patrick Boyer, Olivier Radakovitch, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), International Atomic Energy Agency, Laboratoire de recherche sur les transferts des radionucléides dans les écosystèmes aquatiques (IRSN/PSE-ENV/SRTE/LRTA), Service de recherche sur les transferts et les effets des radionucléides sur les écosystèmes (IRSN/PSE-ENV/SRTE), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), PSE-ENV/SRTE/LRTA, and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)

Subjects
Suspended and deposited sediments, [SDV]Life Sciences [q-bio], chemistry.chemical_element, Soil science, Freshwater systems, 010501 environmental sciences, 010502 geochemistry & geophysics, 01 natural sciences, Concentration ratio, Log-normal k(d) distributions, Adsorption, Geochemistry and Petrology, Dissolved organic carbon, Environmental Chemistry, Radionuclides, 0105 earth and related environmental sciences, Sediment, Particulates, Pollution, 6. Clean water, chemistry, Surface-area-to-volume ratio, Metals, 13. Climate action, Environmental science, Suspended load, Carbon
Abstract

International audience; The contamination of freshwater systems by metals is a worldwide problem due to their toxicity, abundance and persistence in the environment. One of the main processes affecting their residence time in freshwater systems is their solid-liquid fractionation, often modeled by the Kd approach defined as the concentration ratio between the particulate and dissolved phases under the assumptions of reversibility, equilibrium and trace conditions. Because Kd is an empirical parameter that depends on several environmental factors, its variability can cover orders of magnitude for a single element. Such variability is unknown for most case studies, but the modelers need it to evaluate the uncertainty of their calculations. In order to fill this gap, this paper presents statistical Kd distributions for in situ suspended matters as a function of suspended load, dissolved organic carbon and pH. They were obtained using a database containing 8564 Kd values from 50 elements, classified as a function of three exchange conditions (adsorption, desorption and in situ) and two environmental components (suspended and deposited sediments). These distributions and relations can be used to reduce of several order of magnitudes the global variability of Kd values in the case where in situ data are not available. © 2019

Published
2019
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3. Modelling the Fate and Transfer of Substances Discharged into Soil Unsaturated Zones and Water Tables

Author

Cécile Couégnas, Philippe Bataillard, Valérie Guérin, and Mohamed Krimissa

Subjects
Hierarchy (mathematics), Chemistry, Water flow, Water table, Soil water, Vadose zone, Environmental engineering, Site analysis
Abstract

This chapter highlights the complexity of water and chemical phenomena that control the behaviour of contaminants in the unsaturated zone (UZ). Numerous mechanisms are involved in fixing these elements in soils, and many are not fully understood. This area of study is characterised by their hierarchy, or the predominance of one mechanism over another, depending on the bio-physico-chemical conditions of the environment. Understanding this hierarchy requires site analysis and measurements which currently are not always carried out.

Published
2017
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4. Sorption isotherms: A review on physical bases, modeling and measurement

Author

G. Limousin, Véronique Barthès, Mohamed Krimissa, Laurent Charlet, Jean-Paul Gaudet, Stéphanie Szenknect, Laboratoire des Technologies des Traceurs (L2T), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Central des Ponts et Chaussées (LCPC)-Centre National de la Recherche Scientifique (CNRS), EDF (EDF), Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chemistry, technology, industry, and agriculture, Ionic bonding, Thermodynamics, Sorption, 02 engineering and technology, 010501 environmental sciences, 021001 nanoscience & nanotechnology, complex mixtures, 01 natural sciences, Pollution, Chemical kinetics, Adsorption, 13. Climate action, Geochemistry and Petrology, Phase (matter), Desorption, Environmental Chemistry, 0210 nano-technology, Constant (mathematics), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Solid solution
Abstract

The retention (or release) of a liquid compound on a solid controls the mobility of many substances in the environment and has been quantified in terms of the “sorption isotherm”. This paper does not review the different sorption mechanisms. It presents the physical bases underlying the definition of a sorption isotherm, different empirical or mechanistic models, and details several experimental methods to acquire a sorption isotherm. For appropriate measurements and interpretations of isotherm data, this review emphasizes 4 main points: (i) the adsorption (or desorption) isotherm does not provide automatically any information about the reactions involved in the sorption phenomenon. So, mechanistic interpretations must be carefully verified. (ii) Among studies, the range of reaction times is extremely wide and this can lead to misinterpretations regarding the irreversibility of the reaction: a pseudo-hysteresis of the release compared with the retention is often observed. The comparison between the mean characteristic time of the reaction and the mean residence time of the mobile phase in the natural system allows knowing if the studied retention/release phenomenon should be considered as an instantaneous reversible, almost irreversible phenomenon, or if reaction kinetics must be taken into account. (iii) When the concentration of the retained substance is low enough, the composition of the bulk solution remains constant and a single-species isotherm is often sufficient, although it remains strongly dependent on the background medium. At higher concentrations, sorption may be driven by the competition between several species that affect the composition of the bulk solution. (iv) The measurement method has a great influence. Particularly, the background ionic medium, the solid/solution ratio and the use of flow-through or closed reactor are of major importance. The chosen method should balance easy-to-use features and representativity of the studied natural conditions.

Published
2007
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5. Origine de la minéralisation et comportement hydrogéochimique d'une nappe phréatique soumise à des contraintes naturelles et anthropiques sévères : exemple de la nappe de Djebeniana (Tunisie)

Author

Gian Maria Zuppi, Ahmed Maliki, Lucia Fedrigoni, Mohamed Krimissa, and Kamel Zouari

Subjects
Hydrology, geography, geography.geographical_feature_category, Geochemistry, Ocean Engineering, Aquifer, Groundwater recharge, Salinity, Infiltration (hydrology), Seawater, Saltwater intrusion, Ecology, Evolution, Behavior and Systematics, Groundwater, Geology, Phreatic
Abstract

The determination of the origin of the salinity in the superficial aquifer of Djebeniana (South-East of Tunisia), and the understanding of its hydrogeological and geochemical behaviours related to severe natural and anthropic constraints, were approached by the combined survey of some dissolved ions (especially the conservative elements: Br− and Cl−), and by oxygen-18, one of the stable isotopes of water molecules. These ‘tracers’ indicate that: (1) the present recharge during rainwater infiltration brings downward a high content of nitrates and other dissolved salts; (2) two other sources of dissolved salts in groundwater exist, favoured by the intensive exploitation of the phreatic aquifer. The first one is due to mineralised water uprising from a deep and confined aquifer. The sea intrusion is the second source of salinity.

Published
2001
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6. Relation entre nappes superficielles et aquifère profond dans le bassin de Sfax (Tunisie)

Author

Mohamed Krimissa, Jean-Luc Michelot, Kamel Zouari, and My Ahmed Maliki

Subjects
Hydrology, geography, geography.geographical_feature_category, Ocean Engineering, Aquifer, Groundwater recharge, Structural basin, Ecology, Evolution, Behavior and Systematics, Isotopic composition, Geology, Groundwater
Abstract

The study of the isotopic composition ( 18 O and 2 H) of groundwater collected in the Sfax basin (Tunisia), helped to understand the behaviour of the different aquifers. It showed that the groundwater in the deep aquifer is old, probably slow moving and recharged under a colder climate than at present. The increasing exploitation of the shallow aquifers probably favoured upward leakage from the deep aquifer. Isotope balance equations allowed us to estimate the contribution of the deep aquifer to the shallow aquifer recharge.

Published
2000
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