Carmen Sanchez-Valle

Fabrice Gaillard

Sujoy Ghosh

Klaus Metzger

"Fluids and melts in planetary interiors: from crust to core-mantle boundaries"

Aqueous fluids and melts (silicate, carbonate/carbonatites or metallic melts) are major vectors of mass and heat transfer in planetary interiors and play an important role in a variety of geochemical and geodynamical processes that shape the internal and surficial evolution of planetary systems. These processes occur over a broad range of pressure and temperatures that span from shallow crustal conditions (e.g., magma chamber processes, ore deposit formation) to the deep core-mantle boundaries (e.g., planetary differentiation), and they are strongly influenced by the physical, chemical and structural properties of aqueous fluids and melts at relevant pressure and temperature conditions. Over the last decade, major progress has been made in the determination of the properties of aqueous fluids and melts thanks to the development of advanced experimental and computational methods. The goal of this special issue is to highlight some of these advancements and to discuss new views and open questions related to mass transfer and melting in planetary interiors, from crustal conditions to core-mantle boundaries and from the atomic to the planetary scales.

The seventeen contributions of this volume are organized in 4 topical sections that include review papers providing an overview of the current state of knowledge in the field, and accompanied by research papers. Section I addresses the mechanisms of reintroduction of water into planetary interiors via subduction, a primordial process for the generation of fluid and melts at depth (Ohtani, 2015-this issue;

A C C E P T E D

M A N U S C R I P T

ACCEPTED MANUSCRIPT

2 Walter et al., 2015-this issue), and the role of slab-derived fluids on mass transfer from subducting slabs to the mantle wedge and arc magmatism (Jahn et al., 2015-this issue). Section II focuses on novel data on the properties of volatile-bearing silicate melts, with emphasis on (i) the solubility mechanisms and speciation of volatiles, H 2 O, CO 2 , Cl and S (Lesne et al., 2015-this issue;Botcharnikov et al., 2015-this issue;Beermann et al., 2015-this issue) in silicate melts with potential applications on ore-forming processes and volcanic degassing, on (ii) the effect of volatiles on the physical properties (density, viscosity and electrical conductivity) (Bouhifd et al., 2015-this issue;Laumonier et al., 2015a-this issue;Robert et al., 2015-this issue) and the molecular structure (Vuilleumier et al., 2015-this issue;Morizet et al., 2015-this issue) of silicate melts, and on (iv) the timely topic of mixing/mingling of silicate melts and magmas in the crust (Laumonier et al., 2015b-this issue). Section III examines the effect of CO 2 in melting at mantle depth (Hammouda and Keshav, 2015-this issue) and presents new models for the electrical conductivity of carbonated melts (Sifre et al., 2015-this issue), the solubility of CO 2 in kimberlites (Moussallam et al., 2015this issue) and the thermodynamics of mixing between carbonate and silicate melts that rule mantle partial melting (Massuyeau et al., 2015-this issue). Finally, Section IV analyses the interplay between volatiles including carbon, hydrogen and sulfur in magmas and the redox state of the planetary interiors, and examines potential secular variations in these parameters through the ages of the Earth (Gaillard et al., 2015-this issue).

WATER TRANSPORT INTO THE EARTH'S INTERIOR

The reintroduction of water into the mantle via subduction, and its storage and global scale circulation have important implications for understanding chemical mass transfer and for the dynamics of the deep mantle [START_REF] Regenauer-Lieb | Water and geodynamics. In: Water in nominally anhydrous minerals[END_REF][START_REF] Korenaga | Thermal evolution with a hydrating mantle and the initiation of plate tectonics in the early Earth[END_REF]. Changes in the water storage capacity of the mantle with depth may drive melting in a variety of environments, including oceanic basalt sources, the mantle wedge above subducting plates and deeper regions above and below the transition zones [START_REF] Hirschmann | Water, Melting, and the Deep Earth H 2 O Cycle[END_REF].

A C C E P T E D M A N U S C R I P T

ACCEPTED MANUSCRIPT

3 Much effort has been put forth to elucidate the phase relations in hydrous subducted lithologies, to identify the major water carriers and to place quantitative constraints on the fluxes of water into the mantle (e.g., [START_REF] Ohtani | Water transport into the deep mantle and formation of a hydrous transition zone[END_REF][START_REF] Iwamori | Phase relations of peridotites under H 2 O-saturated conditions and ability of subducting plates for transportation of H 2 O. Earth Planet[END_REF][START_REF] Kawamoto | Hydrous Phases and Water Transport in the Subducting Slab. In Water in nominally anhydrous minerals[END_REF][START_REF] Litasov | Effect of water on the phase relations in Earth's mantle and deep water cycle[END_REF]. A series of minerals reactions in hydrous peridotite that stabilize high-pressure phases such as Phase A or phase E provide a path for water into the transition zone [START_REF] Ohtani | Water transport into the deep mantle and formation of a hydrous transition zone[END_REF], where is further stored in wadsleyite and ringwoodite [START_REF] Keppler | Thermodynamics of Water Solubility and Partitioning. In: Water in nominally anhydrous silicates[END_REF], hence creating a long-lived hydrogen reservoir in the solid Earth [START_REF] Kawamoto | Experimental evidence for a hydrous transition zone in the early Earth's mantle[END_REF][START_REF] Ohtani | Stability of dense hydrous magnesium silicate phases and water storage capacity in the transition zone and lower mantle[END_REF]. The recent discovery of hydrous ringwoodite inclusions in a super-deep diamond from Juina (Brazil) provides evidence for a hydrous transition zone, at least in the vicinity of subduction zones [START_REF] Pearson | Hydrous mantle transition zone indicated by ringwoodite included within diamond[END_REF], that is also supported by seismic tomography studies and electrical conductivity measurements [START_REF] Koyama | Water content in the mantle transition zone beneath the North Pacific derived from the electrical conductivity anomaly[END_REF].

The water fluxes into the lower mantle are less well constrained. However, the detection of low seismic velocity and high attenuation anomalies atop of the lower mantle suggest melting, likely related to the dehydration of ultra-high pressure phases in the slab [START_REF] Lawrence | Seismic Evidence for Subduction-Transported Water in the Lower Mantle[END_REF][START_REF] Schmandt | Dehydration melting at the top of the lower mantle[END_REF]. Water transport beyond the transition zone is linked to the stability of phase D (MgSi 2 H 2 O 6 ) in peridotitic lithologies (Ghosh and Schmidt, 2014a;[START_REF] Pamato | Lower-mantle water reservoir implied by the extreme stability of a hydrous aluminosilicate[END_REF]. The recently discovered of ultrahigh pressure phases such hydrous phase H, MgSiO 2 (OH) 2 [START_REF] Nishi | Stability of hydrous silicate at high pressures and water transport to the deep lower mantle[END_REF], and its solid-solution with isostructural -AlOOH [START_REF] Ohira | Stability of a hydrous δphase, AlOOH-MgSiO 2 (OH) 2 , and a mechanism for water transport into the base of lower mantle[END_REF] suggest deep transport of water as cold slabs penetrate down to core-mantle-boundary (e.g., Fukao et al., 2001;[START_REF] Grand | Mantle shear-wave tomography and the fate of subducted slabs[END_REF]. In the review paper that opens this Special Issue, Ohtani (2015-this issue) provides an overview on potential water reservoirs in subducting slabs, the water storage capacity of the

ACCEPTED MANUSCRIPT

4 these phases appears to be stable along a lower mantle adiabat (Walter et al., 2015-this issue;[START_REF] Ohira | Stability of a hydrous δphase, AlOOH-MgSiO 2 (OH) 2 , and a mechanism for water transport into the base of lower mantle[END_REF], or as the temperature of the slab increases rapidly at the core-mantle boundary (Ohtani, 2015-this issue), and a hydrous silicate melt produced upon dehydration melting is likely the host for hydrogen in the lower mantle. In this scenario, and as the hydrous melt comes into contact with metallic iron form the Earth's core, hydrogen could be dissolved into the core as FeNi hydrides [START_REF] Terasaki | Stability of Fe-Ni hydride after the reaction between Fe-Ni alloy and hydrous phase (δ-AlOOH) up to 1.2 Mbar: Possibility of H contribution to the core density deficit[END_REF]). It appears, however, that the amount of hydrogen needed to explain the density deficit in the Earth's core exceeds the amount plausibly supplied via subduction of hydrous components, thus indicating the presence of primordial hydrogen, or other light elements, in the core.

According to experimental studies [START_REF] Schmidt | Experimentally based water budgets for dehydrating slabs and consequences for arc magma generation[END_REF][START_REF] Poli | Petrology of subducted slabs[END_REF] and numerical models [START_REF] Van Keken | Subduction factory: 4. Depth-dependent flux of H 2 O from subducting slabs worldwide[END_REF], only one third of the water stored in the slab is recycled into the deep Earth. Continuous dehydration/devolatilization reactions at shallow depths (< 230 km) result in the release of pulses of fluids into the mantle wedge that trigger melting in the slab and the adjacent mantle wedge in the sub-arc region [START_REF] Tatsumi | Subduction Zone Magmatism[END_REF][START_REF] Kawamoto | Mantle wedge infiltrated with saline fluids from dehydration and decarbonation of subducting slab[END_REF]. Hydrous melting beneath the arc play a principal role in redistributing elements between different mantle reservoirs, and the slab-derived fluids are critical agents of mass transfer and mantle differentiation within the geochemical cycles. Together with water and other volatiles (C, N, Cl, B), fluid-mobile elements are leached during fluid-rock interactions and transported from the slab to the mantle wedge, and eventually recycled back into the surface by erupted magmas. The characteristic geochemical signature of arc magmas informs about the relative mobility of elements [START_REF] Elliott | Stagnant slabs in the upper and lower mantle transition region[END_REF] but only provides a partial picture of the complex fluid/melt-rock interaction processes in deep settings. Experimental studies that combine high-pressure methods and a range of advanced microanalytical techniques have been key to elucidate the chemistry and nature of slab-derived fluids, and the distribution of elements during fluid-rock interactions and melting at depth (e.g., [START_REF] Brenan | Experimental determination of trace element partitioning between pargasite and a synthetic andesitic melt[END_REF][START_REF] Keppler | Constraints from partitioning experiments on the composition of subduction-zone fluids[END_REF][START_REF] Manning | The chemistry of subduction-zone fluids[END_REF][START_REF] Manning | Premelting polymerization of crustal and mantle fluids, as indicated by the solubility of albite + paragonite + quartz in H 2 O at 1 GPa and 350-620°C[END_REF][START_REF] Kessel | Trace element signature of subduction-zone fluids, melts and supercritical liquids at 120-180 km depth[END_REF][START_REF] Spandler | Experimental constraints on element mobility from subducted sediments using high-P synthetic fluid/melt inclusions[END_REF] Herman and [START_REF] Hermann | Sediment melts at sub-arc depths: An experimental study[END_REF][START_REF] References Ardia | A model for the viscosity of rhyolite as a function of H 2 O-content and pressure: A calibration based on centrifuge piston cylinder experiments[END_REF][START_REF] Kawamoto | Separation of supercritical slab-fluids to form aqueous fluid and melt components in subduction zone magmatism[END_REF][START_REF] Sanchez-Valle | Structure and thermodynamics of subduction zone fluids from spectroscopic studies. In: Thermodynamics of geothermal fluids[END_REF][START_REF] Spandler | Element recycling from subducting slabs to arc crust: A review[END_REF]Tsay et al., 2014, and references therein). However, the atomic-scale mechanism that controls the solubility of minerals in high pressure fluids and the transport of chemical elements remains poorly constrained. Few direct observations of the speciation of geochemical tracer in slab-derived fluids at relevant pressure and temperature conditions are available as they require in situ experimental approaches to snapshot the structure of unquenchable phases [START_REF] Sanchez-Valle | Structure and thermodynamics of subduction zone fluids from spectroscopic studies. In: Thermodynamics of geothermal fluids[END_REF]. Alternatively, molecular dynamic simulations have become a powerful tool to model the structure of aqueous fluids and melts (e.g., [START_REF] Guillot | A computer simulation study of natural silicate melts. Part II: High pressure properties[END_REF][START_REF] Mookherjee | Hydrous silicate melt at high pressure[END_REF][START_REF] Jahn | Speciation in aqueous MgSO 4 fluids at high pressures and high temperatures from ab initio molecular dynamics and Raman spectroscopy[END_REF][START_REF] Jahn | Theoretical Approaches to Structure and Spectroscopy of Earth Materials. In: Spectroscopic methods[END_REF], and references therein), including the complexation of trace elements [START_REF] Van Sijl | Molecular modelling of rare earth element complexation in subduction zone fluids[END_REF]2010), in a wide range of pressuretemperature and compositions. In this issue, Jahn et al. (2015-this issue) report results from ab inito molecular dynamics simulations on the complexation of Zr and Hf in high pressure aqueous fluids (basic, neutral and acidic) at mantle conditions. The predicted XANES spectra are consistent with experimental studies [START_REF] Wilke | Zircon solubility and zirconium complexation in H 2 O + Na 2 O + SiO 2 ± Al 2 O 3 fluids at high pressure and temperature[END_REF][START_REF] Louvel | Zr 463 complexation in high pressure fluids and silicate melts and implication for the mobilization of HFSE in subduction zones[END_REF], and together emphasize the key role of the chemistry of the fluid in the mobilization and transport of high-field strength elements (HFSE). and Laumonier et al. (2015a-this issue). Water is not only the main volatile in silicate melts, but it also has a dramatic effect on melt viscosity and density due to its low molecular weight (e.g., [START_REF] Mysen | Silicate glasses and melts: properties and structure[END_REF][START_REF] Giordano | Viscosity of magmatic liquids: a model[END_REF]Malfait et al., 2014a). Direct measurements of the density and viscosity of volatilebearing silicate melts at high pressure and temperature conditions remain challenging and the available data [START_REF] Burnham | Role of H 2 O in silicate melts. 1. P-V-T relations in the system NaAlSi 3 O 8 -H 2 O to 10 kilobars and 1000 °C[END_REF][START_REF] Matsukage | Density of hydrous silicate melt at the conditions of Earth's deep upper mantle[END_REF][START_REF] Sakamaki | Stability of hydrous melt at the base of the Earth's upper mantle[END_REF][START_REF] Ghosh | Stability of carbonated magmas at the base of the Earth's upper mantle[END_REF]Ardia et al., 2008;Malfait et al., 2014a;2014b and references therein). Alternative, measurements on glass samples to above the glass transition temperature (T g ) have provided an extensive database for these properties in geologically relevant volatile-bearing silicate liquids at room pressures (e.g., [START_REF] Dingwell | Melt viscosities in the system NaAlSi 3 O 8 -H 2 O-F 2 O -1[END_REF][START_REF] Ochs | The density of hydous magmatic liquids[END_REF][START_REF] Mysen | Silicate glasses and melts: properties and structure[END_REF][START_REF] Giordano | The combined efects of water and fluorine on the viscosity of silicic magmas[END_REF]2008). In this issue, Bouhifd et al.

A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT 5

VOLATILES AND SILICATE MELTS

A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT 6 is scarce
(2015-this issue) apply an improved dilatometry method to extend the density dataset for water-bearing silicate melts and confirm that the partial molar volume of dissolved water in silicate melts is independent of the chemical composition of the end-member. This uniform volume of dissolved water in silicate melts will The macroscopic melt properties discussed above are intimately linked to the molecular structure of the liquid that is in turn affected by the presence of dissolved volatiles. A prerequisite for a fundamental understanding and for the development of predictive models for these properties at crustal and mantle conditions is thus a detailed knowledge of the structure of the melt and the effect of dissolved volatiles as a function of pressure (e.g. [START_REF] Mysen | Silicate glasses and melts: properties and structure[END_REF]. Structural studies on volatile-bearing silicate melts at high pressure and temperature remain experimentally challenging (e.g., Sanloup et al., 2013) Finally, magma interaction processes in magma chamber and volcanic conduits are examined by

Laumonier et al. (2015b-this issue) presenting the first dynamic mixing experiments between hydrous

A C C E P T E D M A N U S C R I P T

ACCEPTED MANUSCRIPT 9 magmas, and discussing the implication for reservoir replenishment. According to the results, the mixing of hydrous magmas occurs at  170 °C lower than observed for the dry counterparts, and the mixing/mingling appears plausible at crystal fractions below 50 vol.%, while mingling may be plausible at crystal fractions higher than 50 vol.% at the high strain rates that characterize volcanic conduits and magmatic reservoirs .

DEEP CARBON AND CARBONATITE MELTS

More than thirty years ago, a series of key papers were published on the topic of deep mantle carbon, dealing with the petrological, geochemical and geophysical consequences of its cycling through the various Earth's envelops. Seminal papers have revealed that in the presence of CO 2 , mantle melting is possible in the most of the upper mantle, while volatile-free mantle melting occurs essentially at depths shallower than 50 km [START_REF] Green | Phase equilibria and elastic properties of a pyrolite model for the oceanic upper mantle[END_REF]Wallace and Green, 1989). Over the last decade, this topic has regained interest, partly due to the need to better reconstructing paleo-atmospheric CO 2 contents and its role in global geodynamics, which in turn requires better knowledge of this other -deep-carbon cycle which influences the distribution of carbon in the Earth's interior [START_REF] Hauri | Evidence for hotspot-related carbonatite metasomatism in the oceanic upper mantle[END_REF][START_REF] Presnall | Carbonate-rich melts in the oceanic low velocity zone and deep mantle[END_REF]Hammouda, 2004;[START_REF] Dasgupta | Melting in the Earth's deep upper mantle caused by carbon dioxide[END_REF][START_REF] Iacono-Marziano | The role of non-mantle CO2 in the dynamic of volcano degassing: the Mt.Vesuvius exemple[END_REF][START_REF] Ghosh | Solidus of carbonated peridotite from 10 to 20 GPa and origin of magnesiocarbonatite melt in the Earth's deep mantle[END_REF][START_REF] Rohrbach | Redox freezing and melting in the Earth's deep mantle resulting from carbon-iron redox coupling[END_REF][START_REF] Stagno | The oxidation state of the mantle and the extraction of carbon from Earth's interior[END_REF][START_REF] Sifré | Electrical conductivity during incipient melting in the oceanic low-velocity zone[END_REF]. Deep CO 2 -induced melting is a discovery that has critically changed our visualization of the Earth's mantle, which must be a two-phase system (solid+liquid) down to depths where our previous models postulated a single solid-type behavior. The implications of these findings for the broad scale geochemical and geodynamic evolution of the mantle are dramatic and several papers in this special issue pave the way for a better understanding of these processes.

Here, are presented papers addressing the poorly known molecular structure (Vuillemier et al., 2015-this issue;Morizet et al., 2015-this issue, see section 3 for details), physical and chemical properties (Massuyeau et al., 2015-this issue;Moussallam et al., 2015-this issue;Sifré et al., 2015-this issue) of CO 2 -rich melts and they are accompanied by Hammouda and Keshav (2015-this issue) (experimental) literature on the petrology of mantle melting in presence of CO 2 . CO 2 -induced melting has been named incipient melting since small amounts of carbon are expected to prevail at mantle depth. The identified P-T boundary of incipient melting being discussed by Hammouda and Keshav (2015, this volume), have the peculiarities of being almost temperature independent: (i) the ledge, delineating the upper stability field of incipient melts, defines a reaction between CO 2 -rich melts and mantle minerals producing a CO 2 -rich vapor and clinopyroxene occurring in the depth range 50-70 km (Wallace and Green, 1989); (ii) melting, delineating the lower stability field of incipient melts, defines a reaction between CO 2 -rich melts and garnet producing diamonds at depth evaluated between 120 to 350 km depending on the availability of oxygen in the surrounding mantle [START_REF] Rohrbach | Redox freezing and melting in the Earth's deep mantle resulting from carbon-iron redox coupling[END_REF][START_REF] Stagno | The oxidation state of the mantle and the extraction of carbon from Earth's interior[END_REF]. Both reactions (i and ii) are reversible and bracket the mantle domain where incipient melting prevails in the convecting upper mantle. Hammouda and Keshav (2015-this issue) furthermore discuss the special case of carbonatites. The other peculiarity of incipient melting is the melt composition that ranges from silica-poor carbonatites to CO 2 -rich silicate melts (Gudfinnson and Presnall, 2005;[START_REF] Dasgupta | Carbon-dioxide-rich silicate melt in the Earth's upper mantle[END_REF]Ghosh et al., 2014b). mantle conditions. This work extends previous measurements at pressure [START_REF] Gaillard | Carbonatite melts and electrical conductivity in the asthenosphere[END_REF], establishes a clear link with other transport properties such as diffusion and viscosity (Kono et al., 2013), and proposes quantitative interpretation of the rejuvenation process imaged by electromagnetic survey below the South craton (Bologna et al., 2012); a process that may be attributed to small amount of carbonatite melts pervasively wetting the thick lithospheric roots.

A PLANETARY PERSPECTIVE ON VOLATILES, REDOX, AND MAGMAS

Here, we conclude that volatiles such as hydrogen, carbon, sulfur, halogens are all present in the deep species (C-H-S), with a significant reduction of uncertainties appear mandatory at this stage of knowledge.

ACKNOWLEDGMENTS

This special issue derived from a session organized at Fall AGU Meeting 2013 sponsored by the "Mineral and Rock Physics". We thank all the authors that have contributed to this special issue. We are deeply grateful to many referees for assisting in the evaluation of the manuscript and for constructive criticism that helped to improve the quality of the contributions.

  transition zone and the lower mantle, and the role of the solid-solutions between phase H and -AlOOH in the rehydration of the lower mantle. The phase relations and stability of ultrahigh pressure hydrous phases are discussed by Walter et al. (2015-this issue) based on laser heated diamond anvil cell experiments in the systems MgO-SiO 2 -H 2 O (MSH) and MgO-Al 2 O 3 -SiO 2 -H 2 O (MASH), and show that an aluminous hydrous phase, either D or H, will be stable through the lower mantle along a cold subduction geotherm. However, none of A C C E P T E D M A N U S C R I P T

  simplify the construction of general density model for H 2 O-bearing magmas at high pressure and high temperature.Robert et al. (2015-this issue) addressed a major limitation on the development of thermodynamic and physical properties of multicomponent silicate melts relevant to natural system: the combined effect volatiles (water, F and CO 2 ) on the viscosity (and heat capacity) of basaltic melt compositions relevant to calc-alkaline mafic magmas. The results indicate that the effect of F on the viscosity of basaltic melts is much smaller than that of water, whereas the combined effect of both H 2 O and fluorine on the viscosity can be considered additive on wt% basis. Interestingly, typical eruptive concentrations CO 2 have a negligible effect on the viscosity of basaltic melts, at least in the presence of water. Laumonier et al.(2015a-this issue) report experiments to determine the effect of water and pressure on the electrical conductivity of dacitic melts and develop a predictive model that is applied to interpret the electrical signature of potential reservoirs in the crust and water-rich felsic melts in the mantle. They found a much stronger effect on the electrical conductivity of H 2 O in the high concentration ranges than what was suggested from previous measurements collected at low water content[START_REF] Gaillard | Laboratory measurements of electrical conductivity of hydrous and dry silicic melt under pressure[END_REF]) in felsic melts. The authors conclude that electrical anomalies in the crust (e.g., Altiplano-Puna Volcanic Complex, Bolivia) and at the base of the mantle-wedge at subduction zones can be interpreted by the presence of silica-rich, crystallized magma allowing the cycling of water to be tracked by geophysical methods in subduction regions.

  volatiles, H 2 O, S and Cl, in ore-forming magmas, and their partitioning between exsolved magmatic fluids and silicate melts at shallow crustal depths, are addressed in a series of experimental paper byLesne et al. (2015-this issue), Botcharnikov et al. (2015-this issue) and Beermann et al. (2015-this issue).Lesne et al. (2015-this issue) propose a preliminary thermodynamic species-based model for the solubility of sulfur in hydrous basaltic melts as a function of sulfur fugacity, fS 2 calibrated on new experimental data obtained at 1200 °C and 200 to 250 MPa, under oxidizing conditions. The model shows a minimum in S-solubility around the NN0-buffer that is temperature dependent, and a shift of the S 6+ /S 2-equilibrium in the melt with fO 2 as a function of fS 2 . Most importantly, the model suggests that significant amount of sulfur may be present in the gas phase (in addition to H 2 O and CO 2 ) during volcanic degassing. Botcharnikov et al. (2015-this issue) investigate the effect of pressure on the solubility of intermediate melts and the partitioning of H 2 O and Cl into exolved fluids at 1200 °C, from 50 to 500 MPa, and conclude that fluid-melt partitioning of Cl is controlled by the fluid mixing properties and display a pronounced minimum at 200 MPa. The positive correlation between the Cl partition coefficients and the SiO 2 content in the melt at a given pressure indicate that Cl can degas more efficiently from felsic than from mafic magmas. Similarly, Beermann et al. (2015-this issue) report on the partitioning of sulfur and chlorine between aqueous fluids and basaltic melts at 1050 °C, 100 and 200 MPa, at oxidized to moderately oxidized conditions, and link the results to field observations of the eruptive activity of Mt. Etna. It is shown that the partitioning that S and Cl between basalts and aqueous fluids is mostly non-ideal and that Cl increases the solubility of S in the fluid at oxidizing conditions. The experimentally derived S/Cl ratios in fluids and melts compare well with records from the 2001-2003, episodes of passive degassing and or during mild strombolian activity, and contribute to clarify the behavior of volatiles during magmatic eruptions.

  reviewing the last 40 years of

  Massuyeau et al. (2015-this issue) provides the first thermodynamics modelling of carbonated silicate melts.By quantitatively capturing the silica activity, a probe of the energetic costs of the dissolution of silica in carbonate melts,Massuyeau et al. (2015-this issue) define the changes in incipient melt compositions that are in equilibrium with mantle minerals in the vast P-T domain of the upper mantle. This model allows us to capture the narrow P-T conditions where mantle melts shift in composition from carbonatites (below 5 GPa pressures) to kimberlites (above 5 GPa) to basanites at about 2-3 GPa. Kimberlites are addressed byMoussallam et al. (2015-this issue) defining the first solubility law for CO 2 for these enigmatic melts. This achievement is permitted thanks to the possibility of quenching crystal-free glasses having the chemical composition of what we could name a synthetic analogue of kimberlite melts. These melts contain 20 wt% SiO 2 and a similar content of CO 2 , all dissolved as carbonates at the moderate pressure of 200 MPa. The implication is that kimberlite melts can reach very shallow depth, about 3-5 km below the surface, with CO 2 being still dissolved. For these special melts, most of the CO 2 degassing would then occur very shallow in the upper crust, which is the opposite of what is expected from basalts. Finally,Sifré et al. (2015-this issue) provide measurements of the electrical conductivity of carbonatite melts at upper

  Earth and that we need to go towards multicomponent volatile systems facing the complexity of the Earth.All this volatile geodynamics must additionally integrate the redox parameters, a gauge of the availability of oxygen in the deep Earth, which impacts on volatile speciation. Changes in the redox state in the deep Earth can trigger melting, making carbon immobile (diamonds) or mobile (CO 2 -rich melts), can enhance by a factor of 10 the solubility of sulfur in basalts, or can impact of the solubility of H 2 O in nominally anhydrous minerals or favor CH 4 as a stable component carrying together deep hydrogen and deep carbon.Gaillard et al. (2015- this issue) summarize our current knowledge of the redox state of the Earth's mantle and how this is sampled by mantle melts such as basalts. The oxidation state of the Earth's mantle seems to vary weakly with geodynamics yielding indistinguishable redox state for primary melts produced at ridges, intraplate and subduction regions. Furthermore, magma production back to the Archaean seems to display the same redox state as modern magma.Gaillard et al. (2015-this issue) conclude that our conceptual pictures on the parameters that control the redox state of deep rocks and melts (i.e., degree of mantle melting, metasomatism by volatile-rich melts and depth of melting) mostly argue against the observations of redox state of basalts and of their mantle sources. Development of a new generation of oxygen-barometers involving iron or other redox-sensitive elements in silicate phases, as well as volatile


Thierry Lhommeau

Antoine Vautier

Jean-Marc Goujon

Ronan Le

J-M Goujon

R Le Page

Visible And Near Infrared Spectroscopy For PSE-Like Zones Classification At Different Post Mortem Times

Keywords: VIS-NIR spectroscopy, prototype probes, pork meat, PSE-like zones, PLSDA

INTRODUCTION

PSE-like zones result in a loose of muscle fiber structure and pale color in ham meat [START_REF] Franck | Observations préliminaires sur le jambon déstructuré. Description du phénomène et étude de quelques facteurs de variation[END_REF]. It is characterized by a disorganization of the myofiber alignment, disrupted fibers and an increased extracellular space [START_REF] Minvielle | Viandes déstructurées, situation dans cinq abattoirs de l'Ouest de la France : facteurs de risque et proposition d'un modèle, caractérisation colorimétrique, biochimique et histologique[END_REF][START_REF] Laville | Characterisation of PSE zones in semimembranosus pig muscle[END_REF]. SHG microscopy showed that there is no proteolysis in PSE-like zones, as found in control [START_REF] Vautier | Second Harmonic Generation microscopy of PSE-like zones from pork semimembranosus[END_REF]. This defect is a major cause of slicing losses in the French "jambon supérieur" cooked ham process. Industrials need therefore to sort raw meats especially because recipes become less and less salted. VIS-NIR spectroscopy is now known as a reference method for meat composition assessments and for predicting the meat quality parameters such as ultimate pH, color, texture, or drip loss [START_REF] Prieto | Application of near infrared reflectance spectroscopy to predict meat and meat products quality: A review[END_REF]. The aim of this study was to investigate the NIRS ability to predict PSE-like class of deboned hams at different post mortem times. The use of new probes was planned in order to improve the prediction models.

II.

MATERIALS AND METHODS 150 hams were randomly selected at a slaughterhouse and deboned. VIS-NIRS measurements were performed with an ASDI spectrometer Labspec 4 at 12, 16, 20, 24 and 36 h post mortem times. Four probes were used, 2 from ASDI company (named BTS, BTP in this text, fig. 1) and 2 probes were specially designed for this application (named FOS, FOP in this text, fig 2). BTS and FOS probes were applied on the surface of the semimembranosus muscle (center of internal face). BTP and FOP probes were inserted in semimembranosus from the outer side of the muscle to a point at 1 or 2 cm from the surface measurement site. The FOS probe uses the interactance mode, while the 3 others probes (BTS, BTP, and FOP) use the reflexion mode. PSE-like zone quotation (PSE-like zone IFIP scale [START_REF] Ifip | Grille de notation du défaut "déstructuré » des muscles de la cuisse de porc[END_REF]), meat color (L*a*b*, Minolta CR 300), and pH (Sydel pH-meter equipped with a Mettler Toledo and lot 406 electrode) were recorded at each time of NIRS measurement. In order to preserve hams from discoloration and deshydratation, a polyethylene film (8 μm) was laid on the meat between measurements. PSE-like classes 1 and 2 were grouped, as classes 3 and 4 for the prediction model determination. One in four wavelengths in the 350-1800 nm range was kept and used to determine PLSDA prediction models. The 'crossplsda' and 'basic plsda' procedures of the toolbox Saisir of Matlab ® were used for model determination. The calibration sets were composed of one hundred hams randomly chosen, and external validation sets were composed of the 50 remaining hams. During the calibration/cross validation procedure the calibration sets were randomly divided in a 66 hams population for model determination while 33 hams served for cross validation. Cross validation were run one hundred times with PLS component numbers varying from 1 to 20 (figure 3). The PLS component number that was used for the prediction model determination corresponded to the first minimum of mean of false classification rate in cross validation. The prediction model were finally determined using the "plsda" procedure with the appropriate PLS component numbers. External validations of models were run on the external validation sets (50 hams). III.

RESULTS AND DISCUSSION

Table 1 shows performances of prediction models performed with the four probes at 24 h pm. The prediction models developed with the BTS and FOS probes showed better levels of good classification in calibration compared to the BTP and FOP probes (respectively 85,2 and 83,5 vs 76,4 and 80,5). These levels of performance were in accordance with errors of prediction obtained in cross validation (respectively 16,1 and 18,7 vs 25,9 and 24,8). The performance of the BTS probe was not affected by post mortem time between 12 and 24 h pm, table 2. We noted however a degradation of its accuracy at 36 h pm. These good levels of performance were confirmed in external validation (78 to 86 % good classification) but the false negatives/false positives ratio remained unfavorable at every pm times. These results showed however that it was possible to predict PSE-like class at 12 h pm with this probe. In table 3 we observed a similar effect of the pm time on the BTS probe in the calibration results of the FOS probe. Prediction performances were stable between 12 and 24 h pm but decreased at 36 h pm. The level of performance in calibration of the FOS probe was globally comparable to the BTS probe one but 1 or 2 points below. This was confirmed in external validation because the FOS probe showed 6 points lower results in average than the BTS probe. However its ratio of false negatives/false positives was more wellbalanced than the BTS probe and for each pm times. As the PSE-like zone quotation of the 150 hams did not differ in average during the duration of the experiment (α=5 %, data not shown), an attempt for predicting PSE-like class of hams at all pm times has been made, table 6. The prediction model calculated with 24 h pm BTS spectrums showed good accuracy whatever the pm time was (from 78 to 86 % good prediction). Its false negatives/false positives ratios were favorable for the 12, 16 and 20 h pm times. This equation was therefore preferable to the equations calculated at each pm time.

IV. CONCLUSION

In this study we showed that previously tested PSE -like classification by VIS-NIRS [START_REF] Vautier | A feasibility study of the prediction of the technological quality of ham with NIR Spectroscopy[END_REF] can produce good results at different pm times (from 12 to 36 h pm). A prediction model made with 24 h pm BTS surface spectrums was stable and kept good accuracy whatever the pm time was (from 78 to 86 % good prediction). The false negative/false positive ratios were favorable between 12 and 20 h pm.

FOP probe (specially designed to be inserted in meat) gave us a good level of performance (82,9% good prediction in external validation). This probe should be tested for bone-in hams PSE-like zone classification, as industrials need.

Figure 1 .

 1 Figure 1. BTS probe (left) and BTP probe (right).

Figure 2 .

 2 Figure 2. FOP probe (left) and FOS probe (right).

Figure 3 .

 3 Figure 3. Cross validation procedure, 100 times, BTP probe, 24 h pm, n=100 hams. ….. mean of good prediction rate in calibration; ---mean of false prediction rate in cross validation.

Table 1 Prediction

 1

	Good classification rate in external validation (%)	84,0 58,0 82,9 76,0
	PLS component number	2	3	4	1
	False negatives rate (%)	87,5 42,9 57,1 50
	False positives rate (%)	12,5 57,1 42,9 50

accuracy of the four probes at 24 h pm, Probes BTS BTP FOP FOS Good classification rate in calibration (%) 85,2 76,4 80,5 83,5 False classification rate in cross validation (%) 16,1 25,9 24,8 18,7

In Table

1

, BTS probe showed a better level of accuracy in external validation than FOS probe (respectively 84% vs 76% of good classification) but it had more false negatives than the FOS probe : the BTS model seemed not able to detect a large part of PSE-like zones. The FOP probe showed a good level of performance in external validation (83 %).

Table 2

 2 Effect of post mortem time on the prediction accuracy of the BTS probe.

	Post mortem times	12	16	20	24	36
	Good classification rate in calibration (%)	84,0 82,4 83,8 85,2 79,7
	False classification rate in cross validation (%)	16,4 17,9 17,2 16,1 20,8
	Good classification rate in external validation (%)	86	78	82	84	80

st International Congress of Meat Science and Technology, 23-28 th August 2015, Clermont-Ferrand, France

Table 3

 3 Effect of post mortem time on the prediction accuracy of the FOS probe.

	Post mortem times	12	16	20	24	36
	Good classification rate in calibration (%)	83,4 81,3 80,3 83,5 78,3
	False classification rate in cross validation (%)	18,6 19,9 20,1 18,7 23,3
	Good classification rate in external validation (%)	74	80	74	76	74
	PLS component number	1	2	1	1	1
	False negatives rate (%) 30,8 50 38,5 50 15,4
	False positives rate (%)	69,2 50 61,5 50 84,6

Table 4

 4 Effect of post mortem time on the prediction accuracy of the BTP probe.

	Post mortem times	12	16	20	24	36
	Good classification rate in calibration (%)	74,2 81,8 74,5 76,4 74,0
	False classification rate	32,1 25,3 34,5 25,9 30,3

Table 5

 5 Effect of post mortem time on the prediction accuracy of the FOP probe.

	Post mortem times	12	16	20	24	36
	Good classification rate in calibration (%)	80,3 79,8 87,0 80,5 77,9
	False classification rate in cross validation (%)	20,7 20,8 21,1 24,8 24,5
	Good classification rate in external validation (%)	75,6 78,0 73,2 82,9 73,2
	PLS component number	1	1	5	4	1
	False negatives rate (%)	40 66,7 54,5 57,1 63,6
	False positives rate (%)	60 33,3 45,5 42,9 36,4
	The FOP probe showed intermediate results
	between probes used on the surface of meat
	(BTS and FOS) and the BTP, table 5. The levels
	of good classification are stable between 12 to
	36 h pm: from 78 to 87 % of good classification
	in calibration and from 21 to 25 % of false
	classification rate in cross validation. This is
	confirmed in external validation by a 77% rate
	of good prediction in average. The false
	negatives/false positives ratio is moreover well-
	balanced. This probe should be interestingly
	tested on bone-in hams.

Table 6

 6 Test for a use of a single equation (BTS probe, 24 h pm) on the spectrums recorded at others pm times

	Post mortem times	12	16	20	24	36
	Good classification rate
	in external validation of the 24 h pm quotation	84	78	86	84	82
	(%)
	Number of samples	50	50	50	50	50

st International Congress of Meat Science and Technology, 23-28 th August 2015, Clermont-Ferrand, France

ACKNOWLEDGEMENTS

Authors thank the food industry competition cluster "Valorial" for its financial support.


Lydie Le Forestier
email: lydie.leforestier@univ-orleans.fr

Mikael Motelica-Heino

Philippe Le Coustumer

Michel Mench

PHYTOREMEDIATION OF POLLUTED SOILS: RECENT PROGRESS AND DEVELOPMENTS Phytostabilisation of a copper contaminated topsoil aided by basic slags: assessment of Cu mobility and phytoavailability

Keywords: Amendment, Ecological restoration, Metal, Phytoremediation

Purpose: Basic slags are alkaline by-products of the steel industry with potential properties to ameliorate nutrient supply and metal stabilisation in contaminated soils. This study aimed at investigating the potential of a P-spiked Link Donawitz slag and a conventional basic slag called Carmeuse for the aided phytostabilisation of a Cu-contaminated soil at a wood treatment site. The effects of basic slag addition on Cu fractionation, mobility and (phyto) availability were assessed.

Materials and methods: Both slags were incorporated at 1% w/w into the Cu-contaminated soil phytostabilised with Cu-tolerant plants, using either outdoor lysimeters or a field plot.

Untreated soil (UNT), amended soils with the P-spiked Link Donawitz slag (PLDS) and the conventional slag (CARM) respectively, and a control soil (CTRL) were sampled, potted and cultivated with dwarf bean. Physico-chemical analysis, determination of total soil elements and a Cu-sequential extraction scheme were carried out for all soils. Physico-chemical characteristics of soil pore water and Cu speciation (rhizon, ion selective electrode and diffusive gradient in thin film (DGT)) were determined. Shoot dry weight yield and leaf ionome (i.e. all inorganic ions present in the primary leaves) of dwarf beans were investigated.

Results and discussion: The slag incorporation at only 1 % w/w increased the soil pH from 1.5 to 2 units and electrical conductivity in soil pore water by 3 times. The residual Cu fraction increased for both slag amended soils compared to the UNT soil by 6 times in parallel to the decrease of the Cu oxidisable fraction (1.5 times) and to a less extent the reducible fraction.

The incorporation of both slags did not reduce the total dissolved Cu concentration in the soil pore water but significantly reduced the real dissolved Cu concentration ca 5 times, the Cu labile pool as measured by DGT (at least two times) and the Cu phytoavailability. The dwarf bean total biomass was also improved with the slag addition especially for the P-spiked Linz-Donawitz slag.

Conclusions: The addition of both slags in the contaminated soil increased Cu concentration in the residual fraction and thus reduced its potential mobility. Though the total dissolved Cu soil pore water concentration remained identical, its speciation changed as the real dissolved fraction diminished and lowered the Cu bioavailability. The addition of small amount of Pspiked Linz-Donawitz and Carmeuse slags was beneficial for this Cu-contaminated soil in the context of aided phytostabilisation.

Introduction

Trace elements (TE) such as As, Cu, Cr, and Zn can be in excess in contaminated soils at wood preservation sites, especially when Cu-based salts, i.e. Cu sulphate and chromated copper arsenate (CCA), have been long term used as preservatives against insects and fungi, which may result in soil phytotoxicity [START_REF] Kumpiene | Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments -A review[END_REF]). Among the feasible remediation options, phytostabilisation, singly and in combination with mineral and organic amendments (i.e. aided phytostabilisation), is a less invasive, low-cost phytotechnology able to restore (1) the physical and chemical properties of TE contaminated soils and (2) the cascade of biological processes and functions leading to remediated ecosystem services [START_REF] Bolan | Role of inorganic and organic soil amendments on immobilisation and phytoavailability of heavy metals: a review involving specific case studies[END_REF][START_REF] Bolan | Remediation of heavy metal(loid)s contaminated soils -To mobilize or to immobilize ?[END_REF][START_REF] Kumpiene | Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments -A review[END_REF][START_REF] Mench | Successes and limitations of phytotechnologies at field scale: outcomes, assessment and outlook from COST Action 859[END_REF].

In situ (phyto) stabilisation techniques aim at decreasing both the labile TE pool and providing nutrient supply, and simultaneously promoting other beneficial process such as water retention, by incorporating organic and mineral amendments [START_REF] Hattab | Mobility and phytoavailability of Cu, Cr, Zn, and As in a contaminated soil at a wood preservation site after four years of aided phytostabilization[END_REF]). These techniques are able to enhance one or several processes such as metal adsorption through increased surface charge, formation of organic and inorganic metal complexes, sorption on Fe, Mn, and Al oxides, and precipitation [START_REF] Kumpiene | Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments -A review[END_REF]. Further, roots of the implemented vegetation cover can modify the TE mobility by changing soil pH, electrochemical potentials, through element sorption on the root iron plaques and in their apoplast, and functioning of membrane transporters, and TE reactions with their rhizodeposition [START_REF] Hinsinger | Bioavailability of trace elements as related to root introduced chemical changes in the rhizosphere[END_REF][START_REF] Lombi | Dependency of phytoavailability of metals on indigenous and induced rhizosphere processes: a review[END_REF]). Among higher plants, poplars and perennial grasses possess a strong phytostabilisation capability [START_REF] Marmiroli | Growth, physiological and molecular traits in Salicaceae trees investigated for phytoremediation of heavy metals and organics[END_REF]. The immobilization of TE in soil can also be induced through the use of soil amendments that reduce TE mobility and bioavailability [START_REF] Hooda | Trace elements in soils[END_REF]. Several mineral and organic amendments such as lime, coal fly ashes, phosphates, red muds, compost, biosolids, iron grit and Fe/Mn/Al oxides can improve phytostabilisation and production of plant-based feedstock through decrease in TE bioavailability [START_REF] Lombi | In situ fixation of metals in soils using bauxite residue: biological effects[END_REF][START_REF] Bolan | Role of inorganic and organic soil amendments on immobilisation and phytoavailability of heavy metals: a review involving specific case studies[END_REF][START_REF] Bolan | Remediation of heavy metal(loid)s contaminated soils -To mobilize or to immobilize ?[END_REF][START_REF] Geebelen | Selected bioavailability assays to test the efficacy of amendment-induced immobilization of lead in soils[END_REF][START_REF] Brown | In situ soil treatments to reduce the phyto-and bioavailability of lead, zinc, and cadmium[END_REF]Basta et al. 2004;[START_REF] Kumpiene | Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments -A review[END_REF][START_REF] Mench | Successes and limitations of phytotechnologies at field scale: outcomes, assessment and outlook from COST Action 859[END_REF].

Several alkaline slags have been used for amending acidic soils. Linz-Donawitz (LD) slag is an alkaline by-product of the steel industry with potential properties to ameliorate nutrient supply and metal stabilisation in contaminated soils, and it consists of Ca, Al and other metal oxides [START_REF] Negim | Effect of basic slag addition on soil properties, growth and leaf mineral composition of beans in a Cu-contaminated soil[END_REF]. The LD slag incorporation into the soil increases the soil pH and electrical conductivity, and plant growth compared to the untreated soil [START_REF] Marchand | Phytotoxicity testing of lysimeter leachates from aided phytostabilized Cucontaminated soils using duckweed (Lemna minor L.)[END_REF][START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF]. It can be used as a soil additive to render metals less soluble in contaminated soils by precipitation of oxides and by adsorption on their surfaces.

Additionally, in a pot experiment, a P-spiked LD slag was incorporated in a contaminated, acidic sandy topsoil from a wood preservation site to improve physical and chemical soil properties and to in situ stabilize Cu and other TE [START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF]).

This study aimed at investigating the mobility and bioavailability of Cu in phytostabilised contaminated soils amended with basic slags after 5 years of treatment. A P-spiked LD slag and a Carmeuse slag were respectively incorporated into the contaminated topsoils of large outdoor lysimeters and a field plot, cultivated with Cu tolerant plants. The effects of basic slag addition on Cu fractionation, mobility and (phyto) availability were studied for the contaminated soils with and without slag addition together with a control soil. Finally the potential of slags for aided-phytostabilisation of Cu-contaminated soils was assessed.

Materials and methods

Site description and soil sampling

The wood preservation site is located in southwest France, in the Gironde county, nearby the city of Bordeaux (44°43'N; 0°30'W). It consists of 2 ha remaining in activity and 6 ha of derelict areas. [START_REF] Mench | Assessment of ecotoxicity of topsoils from a wood treatment site[END_REF]. Anthropogenic soils are developed on an alluvial soil in terrace (Fluvisol) containing alluvial materials from the Garonne River combined with wind deposits [START_REF] Mench | Assessment of ecotoxicity of topsoils from a wood treatment site[END_REF]. Copper is the main contaminant in topsoils, with total soil concentrations between 65 and 2600 mg kg -1 , showing considerable spatial variation, and exceeding background values for French sandy soils (3.2 -8.4 mg kg -1 ) and threshold values of 35 mg kg -1 above which a negative impact can be observed on plants and animals [START_REF] Baize | Un point sur les teneurs totales des éléments traces métalliques dans les sols[END_REF][START_REF] Baize | Les éléments traces métalliques dans les sols -Approches fonctionnelles et spatiales[END_REF]. Arsenic and chromium did not accumulate in soil, except very slightly at a sub-site where CCA-treated posts were stacked (As = 52 mg kg -1 and Cr = 87 mg kg -1 , [START_REF] Mench | Assessment of ecotoxicity of topsoils from a wood treatment site[END_REF]. Consequently, data for As and Cr were not reported in this study.

Plant communities were assessed [START_REF] Bes | Spatial variation of plant communities and shoot Cu concentrations of plant species at a timber treatment site[END_REF]. The site has been colonized by several plant communities including mainly poplars (Populus nigra) and willows (Salix caprea, S. viminalis). Soil samples were taken from the P1-3 sub-site (for site details, see [START_REF] Mench | Assessment of ecotoxicity of topsoils from a wood treatment site[END_REF]. Total Cu concentrations in the P1-3 topsoil varied between 163 and 1460 mg kg -1 [START_REF] Mench | Assessment of ecotoxicity of topsoils from a wood treatment site[END_REF][START_REF] Marchand | Phytotoxicity testing of lysimeter leachates from aided phytostabilized Cucontaminated soils using duckweed (Lemna minor L.)[END_REF].

Soils were treated with two types of slags. The initial LD slag was furnished by the Centre Technique et de Promotion des Laitiers Sidérurgiques (CTPL, La Plaine Saint-Denis, France), and resulted from electric steel furnace, also known as basic oxygen furnace. It was chemically modified by precipitation of mineral phosphates to increase its P content, and socalled P-spiked LD slag. Details on P-spiked LD slag were done in [START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF]. This slag consisted of a complex mixture of Ca phases, i.e. Ca silicates such as larnite, Ca ferroaluminates such as brownmillerite and sreboldoskite, calcite and hydrated calcite such as portlandite, Fe oxides such as wustite, Si oxide (silica), and P phases such as oxides and phosphates. The phosphate crystals in the P-spiked LD slag mainly belonged to the analcime and apatite families. The Carmeuse slag is a steel slag from a converter produced by the Carmeuse company (norm Class IV, NF U [44][45][46][47][48][49][50][51]2006), and highly crystallized. The crystalline phases identified by X-ray diffraction in this slag were identical to P-spiked LD slag except for the phosphate crystals (personal communication). The chemical composition of both slags was determined by atomic absorption spectrometry after mineralisation of the solid samples. The P-spiked LD slag is mainly composed of Ca, Fe, Si, P, Mg, Al, Mn. Major elements in the Carmeuse slag are Ca, Fe, Si, Mg, and Mn, whereas Al and P are present in minor amounts (Table 1). TE concentrations are below the detection limits for As, Co, Ni, Cu, Pb, and Zn, except Zn in the P-spiked LD slag (24 mg kg -1 ), and Cu in the Carmeuse slag (13.9 mg kg -1 , Table 1).

In a previous study [START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF], the P-spiked LD slag was incorporated into the contaminated soil at increasing rates (0%, 1%, 2%, 3% and 4% in w/w), and even the 1% slag amendment ameliorated physico-chemical soil properties (pH and electrical conductivity) and metal stabilisation. Thus 1% w/w was selected for soil amendment for both P-spiked LD and Carmeuse slags to potentially optimize the Cu immobilization without the adverse effect of over-liming. Both basic slags were carefully mixed into the topsoils (three aliquots successively incorporated to ensure a good homogenization) at 1% w/w. For aided phytostabilisation experiments, two slag treatments were applied whether in outdoor lysimeters for the P-spiked LD slag or in open field for the Carmeuse slag. In March 2007, large vats (75 L, 0.5 m diameter) were filled with three successive layers to consists outdoor lysimeters in triplicates per soil treatment [START_REF] Marchand | Phytotoxicity testing of lysimeter leachates from aided phytostabilized Cucontaminated soils using duckweed (Lemna minor L.)[END_REF]): 5 cm of coarse gravels (1-3 cm, diameter), 22 cm of subsoil (from the 30-60 cm soil layer), and 25 cm of topsoil (from the 0-30 cm soil layer). Gravels and the subsoil were separated by a geotextile. An uncontaminated soil, located on the same alluvial terrace at 2.3 km from the site (12-178 Chemin de Pâte, 33140 Cadaujac, France, 44.727083, -0.521458) was sampled and used as a control soil (CTRL). This area was a natural meadow.

Soil characterization

All bulk soil samples were dried at 40°C for 24 hours, and sieved to < 2 mm prior to analysis (Table 3). Particle size distribution of the < 2 mm fraction was determined by sieving at 250 and 50 m. The soil pH and electrical conductivity (EC) of each sample were determined in distilled soil water extracts (1:2.5 w/v) (NF ISO 10390, 2005), as well as for lysimeter leachates. Total carbon contents were quantified by combustion of about 40 mg of soil sample at 1573 K using an elemental flash pyrolyser analyser (Flash 2000, Thermo Fischer Scientific). The combustion process converted any elemental carbon into CO 2 which was quantified with an infrared spectroscopy cell. Measurements were done in triplicate for each sample and the uncertainties were ± 0.5 mg g -1 . Total organic carbon (TOC) was determined in the soil samples by Rock-Eval pyrolysis (Rock-Eval 6 Turbo, Vinci Technologies, France).

Laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS) analysis was performed on all soil samples. An elemental XR Thermo Specific, following the procedure described by [START_REF] Gratuze | Mass spectrometry with laser sampling: a new tool to characterize archeological materials[END_REF], [START_REF] Aries | Direct determination of lead isotope ratios by laser ablation-inductively coupled plasma-quadrupole mass spectrometry in lake sediment samples[END_REF] and [START_REF] Motelica-Heino | Comparison of UV and IR laser ablation ICP/MS with silicate reference materials and implementation of normalization factors for quantitative measurements[END_REF] was used in combination with a VG UV laser probe laser ablation sampling device operating at 213 nm. Powder samples of 350 mg were put under 8 metric ton pressure, without added binder, to form 13 mm (diameter) x 1 mm (height) pellets. The repetition rate of the laser was fixed to 10 Hz. Calibration took place with certified artificial glass, NIST-610. Measurements were replicated four times to validate the analytical precision of the technique. This procedure enabled to quantify the major and minor elements in the soils. The accuracy of the procedure was assessed with reference soil materials.

Additionally, total dissolved Cu concentrations in lysimeter leachates were determined using HR-ICP-MS (Finnigan Element XR, Thermo Electron, Germany), after filtering with cellulose nitrate Millipore 0.2 m filters.

Sequential extraction schemes of [START_REF] Tessier | Sequential extraction procedure for the speciation of particulate trace metals[END_REF] were used for all soil samples and experimental conditions are summarized in Table 2. All the reagents used to prepare the extracting solutions were products of analytical-grade quality (Merck pro-analysis, Darmstadt, Germany). All solutions and dilutions were prepared using distilled water. Each extraction step was performed in triplicates, starting with 1g of original soil material previously sieved with the 2 mm mesh. The aqua regia step performed on the residue obtained from step 4 for was based on the ISO 11466 method (ISO norm 11466, 1995). Cu concentrations in all extracts from these sequential extraction schemes were determined by HR-ICP-MS.

Pot experiments

Germination tests

For each soil condition, three pots were each filled with 450 grams of soil (dry weight, DW) after sieving at 2 mm. During the first days, the soil moisture was manually maintained at 50% of the water holding capacity with additions of distilled water. Four seeds of dwarf beans (Phaseolus vulgaris L., cv. Limburgse vroege), previously germinated in wet cotton for four days, were transplanted in each pot and cultivated for 10 days in controlled conditions (16 h light/8h darkness regime at 21°C). The soil moisture was raised to 80% during this growing stage. At the end of the growing period, the plants were harvested and the DW yield of bean leaves was determined after drying at 70°C.

Determination of the leaf Cu concentration and amount for dwarf beans

Aliquots of primary leaves (35-150 mg DW) were wet digested into Savillex PTFE 50 mL vessels with 2 mL H 2 0 and 2 mL of concentrated HNO 3 , and heated at 65°C for 16 hours. A volume of 0.5 mL H 2 O 2 (30%) was added to each sample and left open at 75°C for 3 hours.

Finally, 1 mL HNO 3 (48%) with 5 mL H 2 0 and 0.1 mL H 2 O 2 were added, and gently warmed up. After cooling down, the mixture was completed with H 2 O to a final volume of 50 mL. Cu concentration in digests was determined by HR-ICP-MS (Element 2, Thermofischer) and was recovered according to the standard values. Cu concentrations are expressed in mg kg -1 on a DW basis. The Cu mineral mass in the primary leaves was obtained by multiplying their leaf DW yield with leaf Cu concentration: mineral mass of Cu (mg Cu/pot) = total biomass of bean primary leaves (mg biomass/pot) * primary leaf Cu concentration (mg Cu kg -1 ).

Soil pore water characterization

The soil pore water (SPW) was collected before and after the plant testing with Rhizon soilmoisture samplers (SMS, model MOM, Rhizosphere Research Products, Wageningen, The Netherlands) with a pore diameter of 0.15 m. The SMS devices were previously cleaned with 5% HNO 3 and then washed twice with deionised water. The capped end was inserted into each potted soil during filling. Two SMS devices were placed with a 45° angle into each potted soil to collect the SPW (~ 30 mL) before planting and after harvesting the dwarf beans, respectively. For this, a syringe needle was connected to the female lock and inserted into a 10 mL glass vacuum tube, for extracting the SPW by vacuum [START_REF] Cattani | Copper bioavailability in the rhizosphere of maize (Zea mays L.) grown in two Italian soils[END_REF]). The SPW samples were stored at 4°C. A fraction of each SPW sample was acidified to 0.1 mol L -1 HNO 3 for measuring the Cu concentrations by HR-ICP-MS (Element 2, Thermofischer). The rest of the solutions was kept for the following analyses: pH, EC, and dissolved organic carbon (DOC) determined by a Teckmar-Dohrman Phoenix 8000 TOC analyser. A Cu ion selective electrode (Thermo Scientific Orion) was used to determine the labile Cu concentration in the SPW samples. Knowing the soil pH and the total soil Cu concentrations, the copper activity, pCu 2+ , was calculated with the following equation [START_REF] Sauvé | Modelling trace element exposure and effects on plants[END_REF]: pCu 2+ = 3.20 + 1.47pH -1.84 log 10 (total soil Cu)

Labile pool of Cu in the soils

For measuring available Cu in the soils and characterizing the soil exposure, standard cylindrical DGT (diffusive gradient in thin-film) units with Chelex-100 resin gels and an active surface area of 3.14 cm 2 were manually inserted for 24 h directly into the humid topsoil (80%) of each pot after the dwarf bean harvest [START_REF] Davison | Dialysis, DET and DGT: in situ diffusional techniques for studying water, sediments and soils[END_REF][START_REF] Ernstberger | Measurement and dynamic modeling of trace metal mobilization in soils using DGT and DIFS[END_REF]. DGT devices were washed after deployment with distilled water to remove the adhered soil particles. Subsequently, DGT devices were opened to remove the filter and the diffusive membrane. The chelex-100 resin gels were eluted by 1mL of 1M HNO 3 .

The eluate was further diluted 10 times and analyzed by using ICP-MS. The mass of metals accumulated in the resin gel (M, µg) was obtained following [START_REF] Zhang | Performance characteristics of diffusion gradients in thin films for the in-situ measurement of trace metals in aqueous solution[END_REF]:

M = Ce (V HNO3 + V gel )/fe
where Ce is the metal concentration in the eluent (μg mL -1 ) measured analytically, V HNO3 is the volume of HNO 3 (1 mL), V gel is the gel volume (0.15 mL) and fe is the elution factor for metals. The time-averaged concentration at the interface soil diffusive layer (C DGT , μg L -1 ), can be calculated from:

C DGT = (M ∆g)/(D t A)
where Δg is the diffusion layer thickness (0.094 cm), D is the diffusion coefficient of metal in the diffusion layer (×10 -6 cm 2 s -1 ), t is the deployment time (s) and A is the area of the gel membrane exposed to the soil (3.14 cm 2 ).

Statistical analyses

Results were analyzed with the SPSS statistical software package (SPSS, Chicago, IL, USA). Averages were expressed with their standard deviation (± SD) and were compared by ANOVA. In each case the number of replicates (n) is indicated. Statistical tests were considered significant at P ≤ 0.05.

Soil properties

Main physico-chemical properties of the soils are summarized in Table 3. The aidedphytostabilised soils are similar to the UNT soil, in terms of their texture and chemistry, as the PLDS and CARM soils are composed of 99 wt% UNT and 1 wt% slag. All the studied soils had a sandy texture, their coarse fraction representing 67 to 83% of the 2000-250 m fraction.

The UNT soil was slightly acidic with a pH value of 6.4, while the aided-phytostabilised soils, PLDS and CARM, had higher pH values ranging from 7.9 to 8.4, due to the addition of basic slags. The CTRL soil had a lower pH value (5.4), characteristic of a sandy soil from an alluvial terrace. The EC values of the UNT and the CTRL soils were similar and low, related to their texture. The EC increased significantly with the incorporation of both slags (ca 3 times). The UNT and CTRL soils were poor in organic matter, with a mean total organic carbon content of 5 (UNT) and 10 (CTRL) mg kg -1 soil. Total soil Cu reached a high value in the UNT soil with 1460 mg kg -1 . The CTRL soil contained 96.5 ± 7.8 mg Cu kg -1 . This value is slightly higher than the background Cu values in French sandy soils, which varied from 3.2 to 8.4 mg kg -1 (Baize 1997), and may reflect a former vineyard activity. Our results are coherent to previous studies. Basic slags have been used extensively and for a long time to improve the characteristics of soils in the context of agronomical studies (e.g. improvement of the soil pH of acidic soils, soil fertilization; [START_REF] Chichilo | Plant nutrients from slag -Furnace slag as a source of plant nutrients and its liming effectiveness relative to limestone[END_REF]. In particular several alkaline slags have been used for amending acidic soils [START_REF] Ali | Converter slag as a liming agent in the amelioration of acidic soils[END_REF]. However research on the use of basic slags for the remediation of metal(loid)s contaminated soils is more limited.

Basic slag, which consists of Ca, Al and other metal oxides, is an alkaline by-product of steelmaking or a residue of incineration processes. It can be used as a soil additive to render metals less soluble in contaminated soils by precipitation and adsorption on the surface of metal oxides [START_REF] Negim | Effect of basic slag addition on soil properties, growth and leaf mineral composition of beans in a Cu-contaminated soil[END_REF][START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF]. Other liming materials are indeed available on the market and have been extensively used can improve soil properties such as pH, soil electrical conductivity (EC), cation exchange capacity (CEC), exchangeable Ca, Mg, and metal availability to plant, and also increase the crop yield. These include for instance phosphogypsum, calcitic limestone, biosolids and coal fly ashes as beringite [START_REF] Negim | Effect of basic slag addition on soil properties, growth and leaf mineral composition of beans in a Cu-contaminated soil[END_REF][START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF]. However slag treatments increased more soil pH than converter sludge treatments [START_REF] Forghani | Effect of steelmaking slag and converter sludge on some properties of acid soil under tea planting[END_REF]. For [START_REF] Ali | Converter slag as a liming agent in the amelioration of acidic soils[END_REF], the increasing rate of soil pH was proportional to the slag amount used. Additionally, the addition of phospho-gypsum can improve soil properties such as pH and soil electrical conductivity but to a lower extent [START_REF] Alva | Amelioration of acid soil infertility by phosphogypsum[END_REF]. The application of calcium silicate slag reduced the soil acidity and increased available P, Si and exchangeable Ca in soil (Barbosa Filho et al. 2004). Blast furnace slag has also been used to correct soil acidity [START_REF] Carvalho-Pupatto | Soil chemical attributes, root growth and rice yield according to slag application[END_REF]). Our previous work with basic slag and phosphate basic slag on similar soils [START_REF] Negim | Effect of basic slag addition on soil properties, growth and leaf mineral composition of beans in a Cu-contaminated soil[END_REF][START_REF] Negim | In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag[END_REF] shows the potential of these materials to mitigate metal contamination in acidic soils by reducing the mobility and bioavailability of the contaminants.

Cu soil fractionation

Extractable Cu concentrations obtained by sequential extractions (procedure in Table 2) are presented in Fig 1 . In the UNT soil, Cu extractability peaked for the oxidisable fraction (60.3 ± 8.0 %), so Cu was mainly associated with Fe-and Mn-(hydr)oxides. Another significant Cu part was located in the reducible fraction (20.5 ± 1.4 %), which likely corresponds to the fraction linked with organic matter. Both slag-amended soils had similar Cu distribution in the extractable fractions. Copper was mainly located in the residual fraction, with 44.2 ± 1.2 % for PLDS and 46.0 ± 8.0 % for CARM, then in the oxidisable fraction (37.7 ± 0.3 % for PLDS and 37.4 ± 2.3 % for CARM). The slag addition increased significantly the non remobilised Cu fraction. Copper immobilisation after incorporation of clays, organic matter, carbonates, phosphates, and Fe oxides into the soil was reported with precipitation of Cu carbonates and oxy-hydroxides, ion exchange and the formation of ternary cation-anion complexes on the surface of Fe and Al oxy-hydroxides [START_REF] Kumpiene | Stabilization of As, Cr, Cu, Pb and Zn in soil using amendments -A review[END_REF]. The application of calcium silicate slag reduced the soil acidity and increased available P, Si and exchangeable Ca in soil (Barbosa Filho et al. 2004). Copper is assumed to precipitate with hydroxide dissolved from the slag rather than to be adsorbed on the slag surface [START_REF] Kim | Removal mechanisms of copper using steel-making slag: adsorption and precipitation[END_REF]. Moreover blast-furnace slag is an effective sorbent for Cu, Zn, Ni, and Pb ions for a wide range of ion concentrations and pH values [START_REF] Dimitrova | Lead removal from aqueous solutions by granulated blast-furnace slag[END_REF][START_REF] Dimitrova | Lead removal from aqueous solutions by granulated blast-furnace slag[END_REF].

Cu speciation in the soil pore water and soils

Physico-chemical characteristics of the soil solutions, before and after bean cultivation, for the UNT, PLDS and CARM soils are listed in Table 4. Slag amendment into the soils had a significantly increased pH and EC in the SPW. The slag addition also increased the DOC in the SPW, with a maximum value for CARM (9.14 ± 0.36 mg L -1 ) compared to the UNT soil (3.78 ± 0.37 mg L -1 ). The total dissolved Cu concentrations varied from 5.7 to 10.2 mol L -1 on average with fairly large variations notably before the plant testing. No significant difference was found between the UNT soil and both slag-amended soils. Total dissolved Cu concentrations in the SPW were similar before and after the bean cultivation. The Cu 2+ concentrations were low in all SPW, with mean values between 0.08 and 0.72 mol L -1 , with a significant decrease for the PLDS and CARM SPW as compared to the UNT one.

The lower pCu 2+ is, the more Cu is dissolved, so potentially present as ionic form in SPW, and available for root uptake and soil food web. The pCu 2+ presented similar values in both amended soils, much higher than in the UNT soil (pCu 2+ = 6.79; Table 4). Such computed pCu 2+ data agreed with changes in Cu 2+ concentrations obtained by the specific Cu electrode.

Cu speciation in the soil solutions (Fig 2) can be described by the real dissolved Cu fraction (i.e. Cu 2+ concentration measured by the specific Cu electrode), the available Cu fraction (i.e. labile pool determined by DGT), and the colloidal Cu fraction. The colloidal fraction represents the difference between the total dissolved Cu concentration and Cu 2+ concentration, i.e. the Cu complexed with dissolved organic matter and inorganic colloids, as the ion Cu specific electrode measures Cu aquaions only (truly dissolved fraction). In both the untreated and slag-amended soil, the Cu 2+ concentration in the SPW was largely smaller compared to the total dissolved Cu concentration, so Cu was mainly present in complexed forms, likely with colloids and dissolved organic matter. Labile Cu pool measured by DGT was numerically lower in slag-amended soils compared to UNT (P ≤ 0.05) (Fig 2). However, no significant differences were found between both slag-amended soils (PLDS and CARM).

The real dissolved Cu concentration in the SPW was significantly lower in both slag-amended soil compared to the UNT soil (P ≤ 0.05), but no difference was observed between PLDS and CARM. Therefore, both slag amendments significantly reduced the available Cu fraction.

Cu phytoavailability

On average, the total biomass of the bean primary leaves varied between 3.4 (UNT) and 336.7 (PLDS) mg DW/pot (Table 5). The bean growth was very low on the UNT soil and increased on the slag-amended soils. The bean biomass for the CTRL soil presented an intermediate growth, this low biomass was not surprising, because of the relatively high Cu concentration (ca 100 mg kg -1 ) in this control soil, which may inherit a past vineyard activity, which has not been fertilized since a long time. In fact, shoot DW of dwarf beans grown on a kitchen garden soil from the same alluvial terrace was ca 200 mg DW [START_REF] Bes | Remediation of copper-contaminated topsoils from a wood treatment facility using in situ stabilization[END_REF]. In this previous study, the application of alkaline materials, organic matters, phosphates, aluminosilicates, iron grit, basic slag (3.9%) and compost of sewage sludge (5%) combined with iron grit were the most efficient to promote shoot production and limit foliar Cu accumulation in dwarf beans cultivated in a highly Cu-contaminated soil [START_REF] Bes | Remediation of copper-contaminated topsoils from a wood treatment facility using in situ stabilization[END_REF]. In combination with NPK fertilizers the application of a LD slag resulted in highest crop yields and nutrient concentrations in plants [START_REF] Lopez | The recycling of Linz-Donawitz (LD) converter slag by use as a liming agent on pasture land[END_REF]. Both calcitic limestone and basic slag applied in Brazil sugarcane fields generated a beneficial residual effect in the correction of soil acidity, the increase of base saturation, and the yield of sugar cane ratoon [START_REF] Prado | Residual effect on calcium silicate slag as soil acidity corrective in sugar cane ratoon[END_REF].

Foliar Cu concentrations of beans from the UNT soil were very high and variable, from 1408 to 6581 mg kg -1 (Table 5). In contrast, foliar Cu concentrations of PLDS and CARM beans were significantly lower (P ≤ 0.05), five times lower in average. As expected, the leaf Cu concentrations were significantly much lower in the CTRL beans (16 ± 3 mg kg -1 , P ≤ 0.05).

In a previous study on nearby soils, foliar Cu concentrations of ca 60 mg kg -1 were found for beans in a contaminated soil and 12 mg kg -1 in a control garden soil respectively [START_REF] Bes | Remediation of copper-contaminated topsoils from a wood treatment facility using in situ stabilization[END_REF]. Upper critical threshold values for foliar Cu concentrations are below 20 mg kg -1 (Kabata-Pendias and Pendias 2001) and were thus exceeded. Typical foliar Cu concentrations for plants from uncontaminated soils are between 5 and 10 mg kg -1 [START_REF] Sanders | Zinc, copper and nickel concentrations in soil extracts and crops grown on four soils treated with metal-loaded sewage sludges[END_REF]) and were also exceeded.

Copper removal by bean primary leaves (so-called Cu mineral mass) was obtained by multiplying the foliar DW biomass with the foliar Cu concentration. The mineral mass of the UNT,PLDS,CARM and CTRL plants varied from 33.7 ± 28.1,77.7 ± 29.8,39.2 ± 27.4, to 4 ± 1 g Cu for 4 plants, respectively (Fig 3). As expected, the mineral mass was the lowest for the CTRL plants. Concerning both slag-amended soils, the PLDS plants had a Cu mineral mass twice higher than in the CARM plants. This was a direct consequence of the higher leaf biomass for the PLDS plants, since foliar Cu concentrations were similar for both soils. The UNT plants had an intermediate mineral mass, due to a low leaf biomass combined with high foliar Cu concentration. Our results corroborate previous results on slag addition in acidic soils for other metallic cations. For instance the incorporation of LD slag in acidic soils managed under pastures increased the soil pH with and without NPK fertilization [START_REF] Pinto | Effects of Linz-Donawitz (LD) slag on soil properties and pasture production in the Basque country (Northern Spain)[END_REF], increased the exchangeable soil Ca and Mg whereas exchangeable soil Al, Mn, Cu and Zn decreased (Besga et al. 1996). As for our results this is related to the increase of soil pH and the decrease of the acid soluble and oxidable fractions in the slag amended soils. Blast furnace slag has also been used to produce maximum root growth in acidic soils [START_REF] Carvalho-Pupatto | Soil chemical attributes, root growth and rice yield according to slag application[END_REF]).

Conclusions

Changes in soil physico-chemical properties, Cu fractionation and potential mobility, SPW concentration and speciation, and Cu phytoavailability were assessed at a wood preservation site in topsoils of outdoor lysimeters and a field plot phytostabilised with Cu-tolerant plants and amended with a P-spiked Linz-Donawitz and a Carmeuse slag, respectively.

The slag incorporation into the Cu-contaminated soil at only 1 % in weight increased the soil pH from 1.5 to 2 units and electrical conductivity in soil pore water by 3 times. Increased soil pH may favor the sorption of free copper cations onto the slag surfaces as indicated by increased Cu concentration in the residual soil fraction and thus reduce the potential Cu mobility. In fact the residual Cu fraction significantly increased for both slag amended soils compared to the untreated soil in parallel to the decrease of the Cu oxidisable fraction and to a less extent the reducible fraction. The incorporation of both slags into the Cu-contaminated soil did not reduce the total dissolved Cu concentration in the SPW but significantly reduced the real dissolved Cu concentration and also the Cu labile pool as measured by DGT. No significant difference was observed between the effects of both slags. The incorporation of both slags into the Cu-contaminated soil reduced the Cu phytoavailability as the Cu concentration in the dwarf beans leaves decreased significantly and this in the same order of magnitude for both slags. Additionally the dwarf bean total biomass was improved with the slag addition especially for the P-spiked Linz-Donawitz slag and even more than for the CTRL soil. Therefore the addition of a small amount of P-spiked Linz-Donawitz and Carmeuse slags is beneficial for this Cu-contaminated soil in the context of aided phytostabilisation.

  Topsoil treatments in 2007 included (i) untreated soil without plants (UNT) and (ii) soil amended with the P-spiked LD slag characterized by a granulometry less than 160 m (1 g of slag for 100 g of air-dried soil; Negim et al. 2012), hereafter called PLDS, and phytostabilised with Cu-tolerant plants (Agrostis gigantea L. and Populus trichocarpa x deltoides cv. Beaupré). The topsoils of the UNT and PLDS were sampled in March 2012 in six lysimeters (i.e. three replicates of ca 1 kg for each soil treatment). In March 2012, a third topsoil sample was collected (in triplicates) in a plot (1 m x 2 m) of the P1-3 sub-site that had received the following treatment in 2007 also: (iii) incorporation of the Carmeuse slag (1 g of basic slag for 100 g of air-dried soil; granulometry < 0.160 µm) into the 0-25 cm soil layer and annual cultivation with a tobacco-sunflower crop rotation, and called CARM. Additionally, lysimeter leachates were collected in plastic bottles (1.5 L).

Table 5 Fig. 1 Fig. 2 Fig. 3

 5123 Figure captions

  The industrial facility dates back to 1846. Creosote, Cu sulphate (from 1913 to 1980), aqueous solution of Cu, Cr and As salts (standard CCA type C; from 1980 to 2006), and Cu hydroxycarbonates with benzylalkonium chlorides (since 2006) were successively used

Table 1

 1 Main characteristics of the P-spiked Link Donawitz and Carmeuse slags

		P-spiked Link	Carmeuse c
	Parameters
		Donawitz slag a	slag
	pH (in water)	11.6	12.7
	EC b (S cm -1 )	2100	10700
	SiO 2 (g kg -1 )	146	111
	Al 2 O 3 (g kg -1 )	56	14
	Fe 2 O 3 (g kg -1 )	214	366
	CaO (g kg -1 )	307	448
	MgO (g kg -1 )	95	64
	Na 2 O (g kg -1 )	n.d.	2
	MnO (g kg -1 )	25	42
	P 2 O 5 (g kg -1 )	140	12
	Cu (mg kg -1 )	< 5	13.9
	a Negim et al. 2012; b EC = electrical conductivity in water; c standardized product (Class IV,
	norm NF U 44-051, 2006); d n.d. = not determined

Table 2

 2 Extraction conditions of the modified scheme of[START_REF] Tessier | Sequential extraction procedure for the speciation of particulate trace metals[END_REF]

	Fraction	Extractants and conditions
	Exchangeable 1 M MgCl 2 , pH 7, 8 mL, 1 h
	Acid soluble 1 M NaOAc, pH 5, 8 mL, 1 h
	Oxidizable	0.267 M Na 3 C 6 H 5 O 7 and 0.111 M NaHCO 3 , 50 mL, 10 min, 80°C
		then 200 g L -1 Na 2 S 2 O 4 , 3 mL, 30 min, 80°C
	Reducible	30% H 2 O 2 , 5 mL and 0.02 M HNO 3 , 3 mL, 2 h, 85°C
		then 30% H 2 O 2 , 3 mL, 3 h, 85°C
		finally 3.2 M NH 4 OAc, 1 h, 5 mL

Table 3

 3 Main soil characteristics (0 -0.25 m soil layer) EC = electrical conductivity; b TOC = total organic carbon; c n.d. = not determined

	Parameters	UNT	PLDS	CARM	CTRL
	2000-250 m		n.d. d	n.d.
		83			67
	(%)
	50-50 m (%)	14	n.d.	n.d.	24
	< 50 m (%)	3	n.d.	n.d.	9
	Soil pH	6.4 ± 0.4	8.3 ± 0.1	8.0 ± 0.1	5.4 ± 0.4
	Soil EC a (S cm -		184 ± 11.9	201.3±5.5
		61.2 ± 19.8			86.3
	1 )
	Total C (g kg -1 )	32.6 ± 3.5	27.5 ± 4.1	23.4 ± 7.4	83.9 ± 26.2
	TOC b (g kg -1 )	4.9 ± 0.4	n.d.	n.d.	10.4
	Na 2 O (g kg -1 )	1.3 ± 0.9	n.d.	n.d.	1.9 ± 1.1
	MgO (g kg -1 )	3.9 ± 0.6	n.d.	n.d.	4.3 ± 1.9
	Al 2 O 3 (g kg -1 )	165.1 ± 29.3	n.d.	n.d.	132.1 ± 66.8
	SiO 2 (g kg -1 )	661.4 ± 55.9	n.d.	n.d.	673.1 ± 149.2
	P 2 O 5 (g kg -1 )	2.4 ± 0.3	n.d.	n.d.	2.2 ± 0.9
	CaO (g kg -1 )	15.8 ± 21.8	n.d.	n.d.	3.2 ± 0.4
	TiO 2 (g kg -1 )	2.7 ± 0.2	n.d.	n.d.	10.5 ± 14.2
	MnO (g kg -1 )	0.8 ± 0.1	n.d.	n.d.	0.9 ± 0.9
	Fe 2 O 3 (g kg -1 )	40.8 ± 7.9	n.d.	n.d.	41.8 ± 20.7
	Cu (mg kg -1 )	1460	n.d.	n.d.	96.5 ± 7.8

a

Table 4

 4 Physico-chemical characteristics of the soil solutions before and after bean cultivation (n=3; ± standard deviation)

	Parameters	Time	UNT	PLDS	CARM
	pH	before 6.0 ± 0.8	7.2 ± 0.1	7.5 ± 0.2
		after	7.4 ± 0.5	7.4 ± 0.0	7.7 ± 0.1
	EC (S cm -1 ) a	before 406 ± 91	994 ± 31 1673 ± 791
		after	359 ± 63	n.d. d	1271
	DOC (mg L -1 ) b	before 3.78 ± 0.37 6.77 ± 0.20 9.14 ± 0.36
	Cu 2+ (mol L -1 ) c	before 0.67 ± 0.86 0.13 ± 0.02 0.08 ± 0.02
		after 0.72 ± 0.16	0.11	0.13 ± 0.13
	pCu 2+ e	before 6.79 ± 0.15 9.58 ± 0.15 9.14 ± 0.15
	Total dissolved Cu	before 8.9 ± 3.3	10.2 ± 4.7	6.4 ± 4.6
	concentration (mol L -1 ) f after	5.7 ± 0.

Acknowledgements

The authors thank Alain Bret for his technical assistance in sequential extractions, Domenico Morabito for his guidance in statistical analyses, three Master students (Alicia Cuvier, Adrien Renaud, and Guillaume Cagnon), and François Pochon for providing the Carmeuse slag.