Simon Blotevogel

Eva Schreck
email: eva.schreck@get.omp.eu

Stéphane Audry

Giuseppe D Saldi

Jérôme Viers

Pierre Courjault-Radé

José Darrozes

Laurent Orgogozo

Priscia Oliva

Pierre Courjault- Radé

Contribution of soil elemental contents and Cu and Sr isotope ratios to the understanding of pedogenetic processes and mechanisms involved in the soil-to-grape transfer (Soave vineyard, Italy)

Keywords: vineyard soil, mineral nutrition, soil formation, element transfers, Sr and Cu isotopes

niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

In viticulture, soil properties seem to largely influence wine production in terms of quantity and quality [START_REF] Maltman | Minerality in wine: a geological perspective[END_REF], as they are often indicated on wine bottles and are part of appellation schemes [START_REF] Kuhnholtz-Lordat | La genèse des appellations d'origine des vins[END_REF]. Even though the influence of climate, biologic material and regional winemaking techniques on wine characteristics are widely accepted and scientifically demonstrated, there is an ongoing discussion about the contribution of grapevine mineral nutrition, and the potential effect of soil chemistry and geology [START_REF] Bramley | Variation in vine vigour, grape yield and vineyard soils and topography as indicators of variation in the chemical composition of grapes, wine and wine sensory attributes[END_REF][START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF][START_REF] Gonzalez-Barreiro | Wine Aroma Compounds in Grapes: A Critical Review[END_REF][START_REF] Maltman | The Role of Vineyard Geology in Wine Typicity[END_REF][START_REF] Maltman | Minerality in wine: a geological perspective[END_REF][START_REF] Styger | Wine flavor and aroma[END_REF]. Actually, the mechanisms involved in the soil-togrape transfer of elements are complex and remain poorly understood even if there is an increasing interest of the scientific community in understanding the biogeochemical cycles of both nutrients and pollutants, as well as the biological and chemical signatures of terroirs [START_REF] Vaudour | An overview of the recent approaches to terroir functional modelling, footprinting and zoning[END_REF].

One way of possible influence of soil chemistry on wine quality is plant nutrition and translocation of elements through the plant [START_REF] Maltman | Minerality in wine: a geological perspective[END_REF]. Some 17 elements are essential nutrients for plant functioning and are taken up from the soil (Marschner and Marschner, 2012). Concentrations of most nutrients are closely regulated in plant tissues in a process called homeostasis (Marschner and Marschner, 2012). By this self-regulation process (including particularly mineral nutrition, temperature adjustment, transpiration function, etc.), a plant can maintain biological conditions and stability of its dynamic equilibrium facing changes occurring in the environment [START_REF] Castro | Chapter 1 -Regulation of Micronutrient Homeostasis and Deficiency Response in Plants[END_REF]. Mineral nutrients play important roles in biochemical plant functioning as catalyzers, electron transporters or regulators of osmotic pressure (Marschner and Marschner, 2012). However almost the whole periodic table of elements can be found in plants and element concentrations vary systematically between different wines [START_REF] Almeida | ICP-MS determination of strontium isotope ratio in wine in order to be used as a fingerprint of its regional origin[END_REF][START_REF] Coetzee | Intraregional classification of wine via ICP-MS elemental fingerprinting[END_REF][START_REF] Day | Determination of the geographical origin of wine using joint analysis of elemental and isotopic composition. II-Differentiation of the principal production zones in france for the 1990 vintage[END_REF][START_REF] Greenough | Geology and wine 9: Regional trace element fingerprinting of Canadian wines[END_REF][START_REF] Kwan | Pattern recognition analysis of elemental data. Wines of Vitis vinifera cv Pinot Noir from France and the United States[END_REF]. For example, soil carbonate content is an important factor influencing plant functioning, as certain nutrients are scarcely available (especially P and Fe) in carbonated environments and plants have to deploy specific mechanisms to satisfy their needs (Marschner and Marschner, 2012;[START_REF] Strom | Root exudation of organic acids: importance to nutrient availability and the calcifuge and calcicole behaviour of plants[END_REF]. Moreover, interaction among plant nutrients can involve antagonistic or synergistic effects that potentially influence element efficiency in the plant system [START_REF] Rietra | Effects of Nutrient Antagonism and Synergism on Yield and Fertilizer Use Efficiency[END_REF]. So, mineral nutrition is a complex process and soil-to grape transfer mechanisms in vineyards are the result of several interactions and processes, still poorly described [START_REF] Likar | Importance of soil and vineyard management in the determination of grapevine mineral composition[END_REF].

Although differences in elemental contents of wines or grapes, likely do not have a proper taste, smaller variations in element availability may influence the synthesis of compounds essential for grape maturity and wine taste [START_REF] Epke | Retronasal smell and detection thresholds of iron and copper salts[END_REF][START_REF] Sipos | Discrimination of mineral waters by electronic tongue, sensory evaluation and chemical analysis[END_REF]. For example the K/Ca equilibrium is important for acidity in wine but K was also found to be important in polyphenol synthesis [START_REF] Brunetto | THE ROLE OF MINERAL NUTRITION ON YIELDS AND FRUIT QUALITY IN GRAPEVINE, PEAR AND APPLE[END_REF][START_REF] Daudt | Efeito do ácido tartárico nos valores de potássio, acidez titulável e pH durante a vinificação de uvas Cabernet Sauvignon[END_REF]. Furthermore, many elements act as nutrients for fermenting yeasts or catalyzers for synthesis of aromatic compounds [START_REF] Pohl | What do metals tell us about wine?[END_REF]. Variations in metal ion contents have been shown to influence grape properties as sugar and essential amino acid content in grapes, musts and wines [START_REF] Pereira | The 87Sr/86Sr strontium isotopic systematics applied to Glera vineyards: A tracer for the geographical origin of the Prosecco[END_REF].

Mobility and phytoavailability of elements do not only depend on the soil content but are controlled by various soil properties such as pH, Eh, cation exchange capacity or organic matter content [START_REF] Kabata-Pendias | Soil-plant transfer of trace elements-an environmental issue[END_REF][START_REF] Tyler | Plant uptake of major and minor mineral elements as influenced by soil acidity and liming[END_REF]. Therefore, a thorough pedologic investigation is needed to identify soil properties controlling plant nutrition. Soil hydrological parameters have also been reported to widely influence mineral nutrition and fruit composition, as a resultant of soil-plant transfer [START_REF] Ramos | Impact of land levelling on soil moisture and runoff variability in vineyards under different rainfall distributions in a Mediterranean climate and its influence on crop productivity[END_REF][START_REF] Tournebize | Modelling nitrate transport under row intercropping system: Vines and grass cover[END_REF][START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF]. Elemental contents of grapevine organs and their link with soil properties have been subject to several studies, some of them succeeded in identifying a direct link between soil concentrations or extractions whereas other do not [START_REF] Angel Amoros | Bioaccumulation of mineral elements in grapevine varieties cultivated in "La Mancha[END_REF][START_REF] Cugnetto | Tracing the "terroirs" via the elemental composition of leaves, grapes and derived wines in cv Nebbiolo (Vitis vinifera L.)[END_REF][START_REF] Likar | Importance of soil and vineyard management in the determination of grapevine mineral composition[END_REF][START_REF] Mercurio | A 'Geo-Pedo-Fingerprint' (GPF) as a tracer to detect univocal parent materialto-wine production chain in high quality vineyard districts, Campi Flegrei (Southern Italy)[END_REF][START_REF] Vazquez | Assessment of metal bioavailability in the vineyard soil-grapevine system using different extraction methods[END_REF]. Only few studies have investigated grapevine nutrition on contrasted soils [START_REF] Mackenzie | The role of soil chemistry in wine grape quality and sustainable soil management in vineyards[END_REF][START_REF] Peuke | The chemical composition of xylem sap in Vitis vinifera L. cv. riesling during vegetative growth on three different franconian vineyard soils and as influenced by nitrogen fertilizer[END_REF]. In these studies differences in elemental contents and winemaking parameters have been identified [START_REF] Mackenzie | The role of soil chemistry in wine grape quality and sustainable soil management in vineyards[END_REF][START_REF] Peuke | The chemical composition of xylem sap in Vitis vinifera L. cv. riesling during vegetative growth on three different franconian vineyard soils and as influenced by nitrogen fertilizer[END_REF]. However, the vineyards investigated in these studies lie several kilometers apart, thus meteorological conditions were likely different, and no information is given on slope or exposition to sunlight. Thus, as it has been demonstrated that meteorological factors influence elemental compositions of grapevine [START_REF] Boselli | Effect of soil moisture and transpiration on mineral content in leaves and berries of cabernet sauvignon grapevine[END_REF], a new perspective could be to work on the same climate parameters to better isolate the impact of elemental soil-to-grape transfers.

Besides elemental techniques, isotope ratios, and especially Sr isotopes, have been successfully used to determine geographical origin of wines, firstly studied by [START_REF] Horn | SR-87/SR-86 FROM ROCK AND SOIL INTO VINE AND WINE[END_REF] and more recently by various Italian, Portuguese or Canadian research teams [START_REF] Martins | 7Sr/86Sr ratio in vineyard soils from Portuguese denominations of origin and its potential for origin authentication[END_REF]Petrini et al., 2015;[START_REF] Maréchal | High-Precision 87Sr/86Sr Analyses in Wines and Their Use as a Geological Fingerprint for Tracing Geographic Provenance[END_REF]2016;Vinciguerra et al., 2016;Braschi et al., 2018). Actually, radiogenic Sr isotope ratios between 87 Sr and 86 Sr have been used to trace sources in geology and soil sciences for many years. Also in vineyard environments Sr-isotope ratios have been used to support wine quality and guarantee good traceability [START_REF] Durante | Development of 87 Sr/ 86 Sr maps as targeted strategy to support wine quality[END_REF][START_REF] Durante | An analytical approach to Sr isotope ratio determination in Lambrusco wines for geographical traceability purposes[END_REF][START_REF] Durante | Geographical traceability based on 87Sr/86Sr indicator: A first approach for PDO Lambrusco wines from Modena[END_REF][START_REF] Tescione | 87 Sr/ 86 Sr isotopes in grapes of different cultivars: A geochemical tool for geographic traceability of agriculture products[END_REF]. This is possible because stable Sr isotope fractionation related to common low temperature reactions appears to be negligible compared to source signature, also in biological systems [START_REF] Blum | Changes in Sr/Ca, Ba/Ca and Sr-87/Sr-86 ratios between trophic levels in two forest ecosystems in the northeastern USA[END_REF][START_REF] Capo | Strontium isotopes as tracers of ecosystem processes: theory and methods[END_REF]. This makes Sr isotope ratios a valuable tracer of the source of Ca nutrition, as the chemical behavior of the two elements is extremely similar [START_REF] Blum | Changes in Sr/Ca, Ba/Ca and Sr-87/Sr-86 ratios between trophic levels in two forest ecosystems in the northeastern USA[END_REF][START_REF] Poszwa | A comparison between Ca and Sr cycling in forest ecosystems[END_REF][START_REF] Schmitt | Calcium biogeochemical cycle at the beech tree-soil solution interface from the Strengbach CZO (NE France): insights from stable Ca and radiogenic Sr isotopes[END_REF]. This is especially interesting when carbonates are involved in mineral nutrition of grapevine plants.

Moreover, recent studies have underlined the potential use of Cu isotope analysis in the context of polluted agricultural soils [START_REF] Babcsányi | Copper in soil fractions and runoff in a vineyard catchment: Insights from copper stable isotopes[END_REF][START_REF] Fekiacova | Tracing contamination sources in soils with Cu and Zn isotopic ratios[END_REF] and their help in determining the mechanisms of Cu mobility in soils [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF] as well as the mechanisms of elemental transport towards plants or trees [START_REF] Mihaljevič | Copper isotopic record in soils and tree rings near a copper smelter, Copperbelt, Zambia[END_REF]. The discussion on Cu isotope fractionation induced by plants is still ongoing, but first results reported that Cu isotopes fractionate considerably during uptake and translocation: they have been recently used to identify Cu uptake mechanisms [START_REF] Jouvin | Stable Isotopes of Cu and Zn in Higher Plants: Evidence for Cu Reduction at the Root Surface and Two Conceptual Models for Isotopic Fractionation Processes[END_REF], including reduction at root surfaces and preferential translocation of light isotopes to higher foliar levels [START_REF] Weinstein | Isotopic fractionation of Cu in plants[END_REF]. Diverging results from different growth settings also suggest that fractionation of Cu isotopes depends on environmental conditions [START_REF] Jouvin | Stable Isotopes of Cu and Zn in Higher Plants: Evidence for Cu Reduction at the Root Surface and Two Conceptual Models for Isotopic Fractionation Processes[END_REF][START_REF] Li | Cu isotopic compositions in Elsholtzia splendens: Influence of soil condition and growth period on Cu isotopic fractionation in plant tissue[END_REF][START_REF] Ryan | Copper speciation and isotopic fractionation in plants: uptake and translocation mechanisms[END_REF][START_REF] Weinstein | Isotopic fractionation of Cu in plants[END_REF]. Cu isotope analysis is thus an interesting tool to investigate Cu mobility in vineyard environments.

The present study aims at investigating soil formation and mineralogical as well as geochemical differences occurring between two adjacent plots in the Soave area (Veneto, Italy), using complementary techniques. Because different bedrock types underlie the soils of the two plots, the study of the pedological characteristics and of the elemental distribution along the soil-to-grape continuum will allow us to establish a link between soil properties and plant composition under the same metereological and agronomic conditions. In particular, the use of Sr and Cu isotopes will help to better identify the biogeochemical processes and elemental transfers occurring in this vineyard soil-plant system.

Materials and Methods

Area of study

The study was performed in the Cantina Filippo Filippi domain, in the Castelcerino wine growing area, in the Soave appellation (45.464911 N, 11.236905 E). The Soave vineyard is located in the southern foothills of the Alps, in Northern Italy, in the Veneto region. Geologically, the studied site lies between different bedrocks: basalts and volcanic tuff mainly in the Alpone valley and limestone in the western parts of the appellation area [START_REF] Benciolini | Soave Viticultural zoning: the soil as affecting wine quality[END_REF]. Volcanic rocks come from tertiary volcanic activity during the alpine orogenesis with the closest eruptive centers in Alpone valley and north of Cazzano di Tramigna village [START_REF] De | Tertiary volcanism in the veneto: Magmatology, petrogenesis and geodynamic implications[END_REF]. Limestones are from paleogenic and lower Miocene but siliclastic marine sediments and marls are also found in the area as some parts of the Lessini shelf became emerged in early Oligocene whilst others remained on the slope of Thetys ocean [START_REF] Bassi | Components, facies and ramps: Redefining Upper Oligocene shallow water carbonates using coralline red algae and larger foraminifera (Venetian area, northeast Italy)[END_REF][START_REF] De | Tertiary volcanism in the veneto: Magmatology, petrogenesis and geodynamic implications[END_REF]. Basalt outcrops are mainly found to the northeast, tufa to the north and west and limestones in the south and west of the vineyard (Figure 1).

The plots are cultivated with the typical Garganega cultivar in organic viticulture by the same vine grower. Treatment, pruning and harvesting intervals differ only by days and treatment amounts are the same on both plots. Both plots are in viticulture for 65 years. Plant material is still the first generation planted thus no deep ploughing occurred since the beginning of cultivation. Vineyard management has been organic for the last 12 years and grapevine plants are irrigated in case of severe droughts. The soil between grapevine rows is grass covered.

Field pedological description

Soil profiles were studied along two catenas within the two studied parcels (Figure 1), following the main slope. Soil profiles descriptions and pedological investigations were performed both through soil pits until a depth of 50-60 cm for a more complete surface description and an Edelman soil corer was used down to the depth of 120 cm maximum for subsoil study. Structure, texture, roots abundance, biological activity and pedological features (e.g., mottling, coatings, secondary phases precipitations, root and pores distributions) were described directly on the field (i.e., at field moisture). Soil structures below 50 cm depth are indicative structures as structure observation is biased during soil corer sampling. Colors were determined using a Munsell color chart in the year 2000 revised version [START_REF] Munsell | Munsell Soil Color Charts. Revised Edition Gretag Macbeth[END_REF]. The occurrence of carbonate phases and their types (primary versus secondary carbonates phases) was established using 1 M HCl (effervescence method). Samples for bulk densities of surface horizons of B60, B150, C60 and C155 were taken by the cylinder method. Soils were classified according to the World Reference Base for soil resources from FAO/ISRIC/ISSS, 2014 (2015 update).

Hydrological and geomorphological properties

As reported by [START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF], vine water status and especially water deficit stress are key factors of mineral nutrition and grape composition. Among the various methods largely employed to assess the hydric stress, stable isotope ratio in carbon (δ 13 C) are reported to be highly significant [START_REF] Ramos | Projection of phenology response to climate change in rainfed vineyards in northeast Spain[END_REF][START_REF] Ramos | Impact of land levelling on soil moisture and runoff variability in vineyards under different rainfall distributions in a Mediterranean climate and its influence on crop productivity[END_REF][START_REF] Tournebize | Modelling nitrate transport under row intercropping system: Vines and grass cover[END_REF][START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF]. δ 13 C, the 13 C/ 12 C ratio expressed relative to the Pee Dee Belimnite standard (PDB), has been measured as an integrative indicator of water status of grapevine plants. As explained by Farquhar et al., 1989 , 12 C is preferentially taken up by the enzymes involved in photosynthesis and « isotope discrimination » between air and plant occurs. In water stress conditions, this discrimination is less severe and plants contain more 13 C compared to those produced when plant water status is not limiting. [START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF] linked δ 13 C ratios in grapevine plants to stem water potential, sugar content and acidity. That article also defines threshold values of no water stress (δ 13 C < -27 ‰) and severe water stress (δ 13 C > -20 ‰). However, it was reported that δ 13 C values are dependent on grapevine variety (Gómez-Alonso and [START_REF] Gómez-Alonso | Effect of irrigation and variety on oxygen (δ18O) and carbon (δ13C) stable isotope composition of grapes cultivated in a warm climate: Irrigation, variety and grape δ18O and δ13C values[END_REF]. In this study, δ 13 C have been calculated with 13 C/ 12 C values measured on ground leaf and grape samples, on an Isoprime 100 IRMS by Elementar® according to the Equation (1):

Equation 1 δ C = -1" * 1000
Hydric stress occurs when the soil is dry enough, and thus the rate of flow of water out of the soil is a key determinant on the occurrence of water deficit stress. The first order controls on the rate of drainage of soils are their hydraulic conductivity and the topographical slope: the higher they are, the faster will be the drainage. Here, hydraulic conductivity at saturation was estimated by infiltration tests at constant hydraulic head [START_REF] Porchet | Détermination des caractéristiques hydro-dynamiques des sols en place. Mémoire et notes techniques[END_REF] in 45 cm deep standardized boreholes for the different sampling points from C and B catenas, as already reported by [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF].

Moreover, in order to estimates slope distributions, the studied vineyard was mapped using a kinetic differential GPS and an elevation map grid was calculated by kriging between 47968 data points using Surfer 13 software package to propose a vector map indicating slope direction.

All these parameters allow a characterization of the two vineyard plots in terms of their hydrological and geomorphological behaviors.

Sampling of soils, plants and rocks

Soil sampling was performed following the two catenas identified in Figure 1: "B" (basalt) catena for soils over basaltic bedrock (in blue) and "C" (carbonate) catena for soils over calcareous bedrock (in red). The numbers identifying each sampling spot correspond to the distances in meters from the gravel road on top of the parcels. Rock samples of limestone, tufa and basalt were collected from the respective outcrops denoted in geological maps of the Soave region and described by [START_REF] Benciolini | Soave Viticultural zoning: the soil as affecting wine quality[END_REF], and marked in Figure 1. Limestone outcrops are situated within the C catena, basalt outcrops are found uphill from the B catena and tufa outcrops uphill from the C one. This sampling strategy aimed at determining an endmember of each parent material to study pedogenetic mechanisms occurring in this area.

Leaves and grapes were sampled at the end of September (2015), just before grape harvest, as composites from 5 plants surrounding the soil sampling site. Only tissues that visually appeared healthy were sampled at chest height (~ 150 cm from soil) using a ceramic knife. Leaves were washed three times in ultrapure water and thereafter frozen and freeze dried. Grapes were sampled including the pedicel and rinsed with ultrapure water and subsequently freeze dried. Plant samples were ground under liquid nitrogen using an agate mortar.

Soil physico-chemical properties

Soil samples were air-dried for several days under a laminar flow hood and sieved to 2 mm. Soil pH was measured on 1 g in ultrapure water (18.2 MΩ) following ISO 11464 protocol. The cation exchange capacity (CEC) was measured according to the cobalthexamin method, described by [START_REF] Orsini | Utilisation du chlorure de cobaltihexammine pour la détermination simultanée de la capacité d'échange et des bases échangeables des sols[END_REF], [START_REF] Ciesielski | A comparison between three methods for the determination of cation exchange capacity and exchangeable cations in soils[END_REF] and [START_REF] Arrouays | Large trends in French topsoil characteristics are revealed by spatially constrained multivariate analysis[END_REF]: 1 g of soil was shaken in 20 mL of a 0.017 mol L -1 cobalthexamine solution during 1 h, solutions were subsequently centrifuged and supernatant filtered at 0.22 µm. Then cobalthexamine loss from solution was determined by absorbance loss at 475 nm with a Varian Cary 50 spectrophotometer. Soil Organic Carbon and Soil Inorganic Carbon (respectively SOC and SIC) were calculated after subsequent measures of raw and calcined samples on a Horiba EMIA -320V CS automate, according to the method reported in Bao et al. ( 2017), [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF] and [START_REF] Kania | Comparative characterization of surface sludge deposits from fourteen French Vertical Flow Constructed Wetlands sewage treatment plants using biological, chemical and thermal indices[END_REF]. For granulometric analysis, 2 g of soil samples were suspended in distilled water and sieved to 500 µm. The fine fraction was subsequently treated with 10 mL hydrogen peroxide to remove organic matter. Treatment was repeated until no foam or gas formation was observed when adding H2O2. Samples were treated with an acetic acid/ammonium acetate buffer at pH ~4.5 to eliminate carbonates phases. Treatment was then repeated until no effervescence was visible.

Finally, samples were washed in ultrapure water and grain size distribution was measured on a Horiba LA-950 laser diffraction granulometer, as reported by [START_REF] Wanogho | Particle size distribution analysis of soils using laser diffraction[END_REF]. Soil bulk densities were determined after soil drying at 105°C during 48h (until constant mass is reached).

Mineralogy of rock and soil samples

Rock samples were washed with ultrapure water. Approximately 200 g of sieved soil samples (<2 mm fraction, i.e., fine earth) and rock samples were crushed using a planetary mill made from agate. X-Ray Diffraction (XRD) spectra were acquired directly using an INEL diffractometer equipped with a CPS 120 detector at 40 kV and 25 mA applied to a Co anticathode (λKα=0.179 nm; λKß=0.162 nm) for crushed soil samples and a Bruker D8 advance at 40 kV and 40 mA applied to a Cu anticathode (λKα=0.154 nm; λKß=0.139 nm) for crushed rock samples. The crystallized compounds were identified through the comparison with the COD 2013 database. Clay type was identified on oriented thin sections using the <2 µm fraction of decarbonated soil samples. Oriented thin sections were measured as natural sample, heated to 550°C for two hours and treated with ethylene glycol. Diffraction spectra were then measured using the Brucker D8 device with the setting described above.

Elemental contents in rock, soil and plant samples

For total elemental content analyses, 100 mg of each crushed soil or rock sample were digested in a CEM MARS 5 microwave oven using ultrapure acids (9 mL HNO3 : 2mL HCl : 3mL HF). For each digestion run, an experimental blank and a standard (SRM 2709a or BCR-2) were included. Ground plant samples (200 mg) were digested in a CEM MARS 5 microwave oven using suprapure acids (10 mL HNO3 : 3mL HCl : 0.2mL HF). For each digestion run, an experimental blank and a standard (SRM 1515) were included.

After acid digestion, element contents were measured with an Agilent® 7500ce ICP-MS at the GET laboratory in Toulouse and leaves with an iCAPQ Thermo Scientific at Hydrosciences in Montpellier using an In-Re internal standard to correct data for instrumental drift and plasma fluctuations. Ca, Mn and Fe contents in soil samples were measured using an ICP-OES Horiba ultima 2. Element concentrations were expressed in dry weight (mg kg -1 , DW). Quality and measurement traceability were ensured by measuring replicates of SLRS-5 river water standard. N content of leaves was measured during C-isotope analysis Isoprime 100 IRMS, as described above for C.

Sr isotope analysis

From the above described sample digests, aliquots were taken to contain 300 ng of Sr. They were dissolved again in 0.5 mL of 2M HNO3 and added to a column containing 150 µl of Sr-Specific resin. The matrix was eluted using 0.4 mL of 2M HNO3 followed by 1.5 mL of 7 M HNO3 and another 0.3 mL of 2 M HNO3. Strontium was then recovered in 1 mL of 0.05 M HNO3. All acids used for purification were double sub-boiled prior dilution. Samples were evaporated to dryness and deposited on W-filaments.

Measurements of Sr isotope composition were carried out on a Thermo® Triton thermal ionization mass spectrometer (TIMS). NBS 987 standards were run to verify the precision of the method. As differences in Sr isotope ratios are mostly radiogenic (from 87 Rb decay), Sr-isotope ratios are expressed as ratios between 87 Sr and 86 Sr.

Cu isotope analysis

For Cu isotope analyses, aliquots of digested samples containing 500 ng of Cu were purified using anionic AG MP-1 resin. Separations were carried out at least twice per soil sample (elution with HCl and H2O2) using AG MP-1 resin with Biorad® column, according to the protocol adapted from [START_REF] Maréchal | High-Precision 87Sr/86Sr Analyses in Wines and Their Use as a Geological Fingerprint for Tracing Geographic Provenance[END_REF] and detailed in [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF]. Recovery was checked to be 100 ± 5% and BCR-2 standards were run to assure result quality. Soil profiles from the B catena also show granular to subangular blocky structure within the first 10 cm.

The intermediate and deepest horizons investigated generally display angular blocky structures or quasi massive soil structure. Indeed, cambic horizons located beneath 30 cm depth present massive structure when humid and show wedge-shaped aggregates and shrink-swell cracks when dry suggesting vertic properties. However, the deepest horizon of B60 seems to features a single grained structure and the two deepest horizons of B150 have powder-like to more aggregated structure (supposed blocky angular).

Texture varies from loamy clayey in topsoil horizons to clayey in protovertic horizons. Again, the bottom layer of B60 differs from the rest of the studied soil profiles being clayey-loamy-sand and thus much coarser. Colors are darker than calcisols from the C catena (mainly 10 YR 3/2 and 10YR 2/1). Only B60 bottom layer is brighter with 10 YR 5/6. The occurrence of shrink swell cracks and wedge shaped aggregates was established for most of the subsoil horizons after 30 to 40 cm depth. However, those structures resulting from shrinking and swelling properties of clays are not considered as currently active because of a quasi-constant humidity all year long (climate with no dry season and irrigation) so that vertic properties are poorly expressed at the soil profile scale. A secondary precipitation of carbonate phases was observed at various depth along the soil profile (see Figure 2) suggesting protocalcic properties within these soils. Colluvic material was only established for B150. B20 and B60 were identified as Vertic Cambisols protocalcic whereas B150 was identified as a Vertic Cambisol colluvic (WRB soil classification), as described in Figure 2.

Vineyard hydrological and geomorphological properties

The results of soil hydraulic conductivity are reported in Table 1. The soil permeability K is slightly lower in vertic soils (8 × 10 -7 to 10 -5 m s -1 ) than in calcareous ones (1 to 7 × 10 -5 m s -1 ). The lowest hydraulic conductivity is measured where the infiltration test depth includes the vertic horizon. However, these values remain close, suggesting that the soil hydraulic properties are quite the same between the two vineyard plots.

Moreover, results of δ 13 C measurements (Table 3) show no significant difference between the two plots (B or C catena). The measured δ 13 C values ranging between -26. 30 and -27.64‰ and -24.27 and -25.82 for respectively the leaves and the grapes from the 2 plots are in the upper range of the thresholds defined by van [START_REF] Van Leeuwen | Vine water status is a key factor in grape ripening and vintagequalityfor red Bordeaux wine. How cen it be assessed for vineyard management purposes?[END_REF] for water deficit. This suggests that the plants did not suffer severe water stress and that there is no significant difference in water stress between the two plots (Table 3; non-parametric Mann-Whitney U-test: p-value=0.5 and 0.35 for leaves and grapes, respectively).

Concerning geomorphological properties, the vector map indicating slope direction is presented in Figure 3. Elevation of the vineyard plots is the highest in the north east and the lowest in the south west. There is no strong variability of slope between the two vineyards, since the variation of elevation are mainly related to localized, steep banks rather than through distributed and strongly variable sloping.

Mineralogical and physico-chemical properties of soils

The mineralogical and physico-chemical characteristics of the soil samples are summarized in Table 1.

The mineralogy of parental rocks and soils is reported in the XRD spectra of Figure 4. The XRD spectra of limestones taken from the outcrops between the parcels exclusively show calcite peaks. The tufa samples also contain the peaks typical of calcite, but also exhibit peaks of clay minerals identified as smectites (Figure 4b). Only the basalt samples have more complex mineralogy (Figure 4a) containing albite, titanite, chabazite and diopside. In most soils of the C catena calcite remains the main mineral.

Only in the topmost horizon of C60, quartz is the major phase (examples of diffraction spectra are shown in Figure 4). In all soils, peaks belonging to smectite-type minerals are detected and clay mineralogy appears to be the same (i.e., montmorillonite type smectite) in both catenas according to orientated thin section analysis (data not shown). Furthermore, albite and titanite peaks are present in C60 and C155.

Diffraction patterns for soils of the B catena show the same minerals phases as basaltic rock, except chabazite. Smectite is detected in all of those soils and some horizons show calcite. The presence of calcite was expected as the vineyard was irrigated in case of need. In the lowest horizon of B60, calcite is more abundant than the two other minerals. In B60 50-70 cm, quartz is found to be the most abundant mineral.

All studied soil horizons have pH values higher than 7 (Table 1). The lowest pH values within a soil profile are systematically found in topsoils and ranges from 7.2 in C60 and C220 to 7.5 in B20. The pH values of subsoils vary between 7.6 in B150 (40-50 cm), C60 (30-50 cm) and C155 (10-50 cm). The highest pH value is 8.1 and was measured in the deepest horizon of C220. Cation exchange capacity is around 80 cmol kg -1 in most horizons. However, the deepest horizons of B150 have slightly lower CEC with values of 70.0 and 72.2 cmol kg -1 , whereas the soil C220 has the lowest CEC with values between 66.0 cmol kg -1 in the topsoil and 55.8 cmol kg -1 in the lowest soil horizon. The soil C220 is also the soil with the highest inorganic carbon contents comprised between 3.7% in the topsoil and 5.6% in the lowest soil horizon.

Inorganic carbon contents of around 2% (wt) are measured in the deepest horizon of C60 and the two deepest horizons of C155 alongside with the two topmost horizons of B20 (Table 1). Values between 1.4 and 1.6% are measured in the two upper horizons of C155 and the lowest horizon of B60. All other horizons have inorganic carbon contents of less than 1%. Organic carbon contents decline in all soil columns with depth. Organic carbon contents in topsoils ranges from 7.1% in B60 (0-10 cm) to 2.0% in C155 and systematically declines to < 0.1% in the lowest soil layers. Only B20 (110-120 cm) and C220 (50-60 cm) contain measurable amounts of organic carbon (0.8 and 0.2% respectively).

Granulometric analyses after carbonate removal show that most of the soil horizons have similar granulometric distribution, characteristic of silty clay to silt-clay-loam textures (Figure 5): between 30 and 40% of clay and very little sand (generally <10%). Higher clay contents are found in the soil B150 as well as the topsoil of C60 that (about 50%), which can be classified as having a heavy clay texture. The lowest clay contents are found in lowest horizons of B60 and C155 (15 and 10 %, respectively) and horizons of C220 have slightly lower clay contents (24-28 %). The soils from the C catena have slightly higher sand contents than the soils from the B catena. The highest sand contents of 11 to 19% are found in B60 (70-90 cm), C155 (50-70 cm) and C220 (20-50 cm).

Surface A horizon from both catena soils display very low bulk density values from 0.7 to 1, in accordance with the intense biological activity (abundant worm casts) observed in the first ten centimeters of the soils. Bulk densities for the Bik horizons of the B catena soil profiles are relatively low with values from 1 to 1.2 in accordance with the vertic properties of these soils, implying low bulk density during humid periods. Indeed, the volumetric water contents of the samples were estimated at approximately 40 to 50% during the sampling campaign. Subsurface horizons from the C catena show higher bulk densities values from 1.2 to 1.7.

Elemental contents in rocks and soils

The results of elemental contents in rocks and soils are reported in Table 2. The elemental concentrations of the major elements Mg, K, Ca and Mn in the basaltic rock (44.2, 9.9, 55.3 and 1.25 g kg - 1 respectively) are within the range of values found in other studies in the area [START_REF] De | Tertiary volcanism in the veneto: Magmatology, petrogenesis and geodynamic implications[END_REF].

Conversely, we find contents of Fe, Al and P that are 1.5 to 2 times higher than reported in the literature [START_REF] De | Tertiary volcanism in the veneto: Magmatology, petrogenesis and geodynamic implications[END_REF]. Concentrations of all measured elements except Ca (394 g kg -1 ) are relatively low in the limestone. Especially, the content of the transition metals Mn (0.67 g kg -1 ), Fe (3.32 g kg -1 ), Cu

(2.57 mg kg -1 ) and Zn (3.81 mg kg -1 ) is low compared to the basalt (1.25 and 81.9 g kg -1 respectively for Mn and Fe, and 49.1 and 120.4 mg kg -1 for Cu and Zn). Molybdenum is the only element besides Ca that is more concentrated in the limestone (0.25 mg kg -1 ) than in the tufa (0.17 mg kg -1 ), but still less concentrated than in the basalt (1.10 mg kg -1 ).

The tufa rock concentrations of elements are intermediate between those of basalt and limestone for most elements. Ba, Cu, P and Al have almost identical concentrations in the tufa as in the basalt, whereas all other elements are more concentrated in the basalt. In basaltic rocks, the most abundant element measured is Fe, in contrast to tufa and limestone where Ca is far more abundant. In soil profiles, Ca and Fe are the most abundant elements in the order of hundreds of grams per kg of bulk soil. Some of the elements show distinct variations with depth. This is the case for Cu and S which are much more concentrated in the top of the soil columns. However, also K, Zn and, to some extent P, show increasing concentrations in the top of the soil profiles. For Ca the trend is inversed, with higher concentrations in the bottom horizons of the soils, especially on catena C. Other elements are more or less equally distributed through the soil profile. Magnesium is depleted in the top soil horizons of B150 and C60.

There are few significant differences in elemental content between catena B and catena C. One sided non-parametric Mann-Whitney U-test performed over all soil horizons of the respective plot, that Ca and Ba contents are significantly higher in C catena soils. On the other hand significantly higher concentrations in the B catena were detected for Mn, Fe, Sr and Mo.

Elemental contents in leaves and grapes

Elemental contents in leaves of both catenas are of the same order of magnitude (Table 3). However, some significant differences identified using a Mann-Whitney U-test. K and Zn concentrations in leaves of the C catena are higher than those in the B catena, whereas Sr concentrations are higher in leaves from the B catena. No significant differences were detected for other elements contents in Ieaves. The values measured are around average contents reported in the literature for Mg, P, Mn and Zn (Marschner and Marschner, 2012). Cu and Ca contents (75 mg kg -1 and 32 g kg -1 , respectively) are higher compared to the corresponding values of 6 mg kg -1 and 5 g kg -1 reported in literature. Nitrogen, K and Fe concentrations are low, with respectively, 14.3 g kg -1 , 7.2 g kg -1 and 43.7 mg kg -1 , relative to literature values of 23-43 g kg -1 , 10 g kg -1 and 100 mg kg -1 [START_REF] Grechi | Effect of light and nitrogen supply on internal C:N balance and control of root-to-shoot biomass allocation in grapevine[END_REF]Marschner and Marschner, 2012).

For grapes, the elemental contents are consistent with the literature [START_REF] Cugnetto | Tracing the "terroirs" via the elemental composition of leaves, grapes and derived wines in cv Nebbiolo (Vitis vinifera L.)[END_REF][START_REF] Scherz | Trace elements in foods: Zinc contents of raw foods-A comparison of data originating from different geographical regions of the world[END_REF]. However, comparison to most sources is difficult due to different sampling strategies (including pedicels, juice only etc.) and differences in notation (dry matter vs. fresh weight) (i.e. [START_REF] Almeida | Multielement Composition of Wines and Their Precursors Including Provenance Soil and Their Potentialities As Fingerprints of Wine Origin[END_REF][START_REF] Bertoldi | Accumulation and Distribution Pattern of Macro-and Microelements and Trace Elements in Vitis vinifera L. cv. Chardonnay Berries[END_REF]. Significantly higher concentrations of K, Al and Mo are found in the C-catena whereas Ca and Sr concentrations are higher in grapes from the B-catena.

Sr and Cu isotopes in the soil-plant continuum

Isotope ratios for Sr and Cu are reported in Table 2 for soils and rocks, and in Table 3 for plant leaves. Cuisotope ratios could not be measured in grape samples because of the low concentrations of Cu in this plant compartment and the interference of residual organic matter with the separation protocol.

Strontium isotope ratios are the highest in limestone with 87 Sr/ 86 Sr of 0.7070. Sr isotope ratios are equal to 0.7032 in basaltic rock and 0.7067 in tufa rock, closer to limestone. Moreover, in soils as well in leaves, Sr isotope ratios are always higher in samples from the C catena than in those of the B catena. This difference is significant using a Mann-Whitney U-test.

Copper isotope ratios in soils were already published in [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF], see there for more details. Within the same soils, the values vary slightly but significantly between different soil types though 2SD interval overlap. If we discard the B60 70-90 horizon for being obviously calcareous, the pvalue (Wilcoxon Rank Sum test) is <0.002 comparing mean isotope ratios of 0.18‰ for calcaric cambisols and 0.28‰ for vertic soils. The B60 surface horizon contains the heaviest measured Cu signature for soil samples present vineyard (i.e., 0.37 ± 0.05‰). This is also the horizon containing the most Cu and organic carbon, suggesting an organo-complexation of Cu with humic acid, as already suggested by Bigalke et al. (2010b) and [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF]. The lowest isotope ratio is found in the deepest horizon of B60 (0.12 ± 0.04‰). That horizon contains a considerable amount of inorganic carbon (1.6%), and calcite is the most abundant C-bearing phase. In plant leaves, Cu isotope ratio varies more than in soil samples, varying from -0.86 to -1.83 for leaves of vine plants taken respectively in C155 and C60 soils.

Discussion

Influence of geology versus pedogenetic processes on soil properties in the Soave vineyard

In former studies of the Soave vineyard, only the presence of limestone and volcanic rocks was highlighted [START_REF] Benciolini | Soave Viticultural zoning: the soil as affecting wine quality[END_REF]. However the presence of tufa rocks fits into a greater geological context with variations in land and ocean levels that left behind a variety of calcareous and siliclastic rocks in the Lessini mountains [START_REF] Bassi | Components, facies and ramps: Redefining Upper Oligocene shallow water carbonates using coralline red algae and larger foraminifera (Venetian area, northeast Italy)[END_REF][START_REF] De | Tertiary volcanism in the veneto: Magmatology, petrogenesis and geodynamic implications[END_REF].

As explained above, hydrological and geomorphological properties appear to be similar between the two vineyards plots, as suggested by the values of soil hydraulic conductivity (Table 1 and δ 13 C measurements in leaves and grapes in Table 3). Even though there are slight differences in hydraulic conductivity, plants do not suffer severe water stress and especially there are no significant differences in δ 13 C measurements between plants from the two plots. Thus hydraulic parameters were considered of no influence in our study, and their impact was not investigated in terms of soil-to-grape transfer of horizons. This is attributable to a control of carbonate phases on soil pH in all soils. The chemical composition of the soils is also surprisingly similar. The only difference is the higher Ca contents in carbonated horizons whereas the contents in metals such as Al, Mn and Fe are relatively high in all soil samples. The C220 soil contains more Ca and less transition metals than the other soil profiles, indicating that this soil is less influenced by basaltic material than all other soils. All soils seem to have formed under mixed influence of the three bedrocks present in the study area.

In the C catena a distinct increase in Ca content with depth as well as the increase in relative importance of the calcite peaks in XRD spectra indicate that carbonate weathering is one of the soil forming processes involved in this catena (Figure 4). However, the relatively high metal and smectite contents as well as the increase in Al/Fe ratios in soils compared to limestone indicate that limestone weathering is not the only soil forming process. The influence of the tufa rock weathering would possibly explain these observations and is supported by the 87 Sr/ 86 Sr values close to tufa and limestone rocks in the soils of the C catena. Besides, soils of the C catena mainly in more upslope positions contain trace of feldspars and titanite typically inherited from basaltic rock (Figure 4). The presence of minerals inherited from the basalt indicates that there is at least some contribution of basalt to the soils from the C catena.

The soil forming processes along the B catena are also complex. The finer texture of soils downslope (B150) indicates that erosive transport (colluvic processes) occurs. The presence of calcic horizons together with non-calcic horizons in upslope soils (B20 and B60) indicates an influence of limestone through erosion processes (particulate transport) or secondary carbonate precipitation implying the circulation of water charged with Ca and dissolved carbonate species. The presence of quartz also confirms an erosive contribution from sedimentary rocks.

Copper and S contents decrease with depth within the soil profiles, which is likely due to fungicide treatment. XRD analyses on oriented thin sections indicate no difference between smectite types from the B and the C catena (data not shown). This suggests that all soil smectites formed under the same conditions, possibly through basalt weathering. Some contribution of inherited smectites from tufa rock weathering during pedogenesis is expected in catena C. Therefore, such inherited smectites entrapped in the tufa rocks might have formed from past basalt weathering, which is still occurring in this area. Tufa rocks seem to have an important role in pedogenesis of the studied soils.

A mixing diagram (Figure 6) was drawn using the contents of Ca and Sr and the 87 Sr/ 86 Sr ratios of the three bedrock types to illustrate their influence on the composition of the corresponding soil horizons and grape leaves (see [START_REF] Langmuir | A general mixing equation with applications to Icelandic basalts[END_REF], for details on mixing diagram interpretation). Almost all soil horizons lie outside of the mixing triangle as a decrease in Ca/Sr ratios is expected during weathering (e.g. Pett-Ridge et al., 2009). The C220 horizons lie on the mixing line between the limestone and the tufa with decreasing Ca/Sr ratios towards the surface. The 87 Sr/ 86 Sr ratios are unchanged compared to the limestone bedrock, as already observed for various soils from typical bedrock endmembers (Braschi et al., 2018). In our case, this observation confirms that weathering of limestone is a major soil forming process for the C220 soil. In addition, for the two topmost horizons of C60, the 87 Sr/ 86 Sr ratios are in the range of values measured in tufa and limestone. Their shift towards lower Ca/Sr values indicates that weathering of one or both of these rocks played a role in their formation. For the other horizons, the 87 Sr/ 86 Sr values differ from all bedrocks indicating a mixed influence of bedrocks. The deeper horizons of C60 lie together with the C155 horizons and rather close to the 87 Sr/ 86 Sr values of tufa and limestone, indicating a major influence in their formation by those rocks. If they were derived mainly from the tufa bedrock, weathering played a minor role in their formation as Ca/Sr values are not far from those of tufa rocks. If the main source material was limestone, weathering in those horizons was even stronger than in C220 horizons. A basalt influence is also a possibility to explain the observed soil signatures. It would be coherent with the presence of mineral phases from basalt such as titanite in the soils from the C catena.

Isotope ratio 87 Sr/ 86 Sr values of all B catena horizons align between the basalt pole and a pole with lower Ca/Sr ratio and higher 87 Sr signature than tufa and limestone (Figure 6). We suggest this pole corresponds to secondary carbonate formation in basaltic soil. B150 soils are closest to the basalt pole.

Whereas B20 and B60 that were more strongly influenced by carbonate rocks and secondary carbonates have higher 87 Sr/ 86 Sr values. This illustrates the complex interplay between at least three parental rock sources and pedogenetic processes (weathering, secondary phase precipitation, erosive transport) in the area. Erosive transfer, pedogenesis and complex bedrock geometry make the vineyard zones less clearly distinct in their biogeochemical properties than expected from macroscopic pedological observations.

Influence of soil characteristics on plant elemental content

The complex pedogenetic processes in the Soave soils have, to a large extent, homogenized elemental contents of bulk soils even though structure and color are clearly different according to field observations. A dominant influence of bedrock chemistry on soil chemistry is visible only for few elements. One remaining difference is the Ca content as marker of the degree of carbonate content. The increase of Ca contents with depth in the C catena reveals a weathering gradient within the soil column, underlining the fact that those soils have not been deeply ploughed recently. The presence of carbonates is an important control on pH and thus on the mobility of elements [START_REF] Kabata-Pendias | Soil-plant transfer of trace elements-an environmental issue[END_REF]. Cu and S contents decrease with depth within the soil profiles. Such decrease is due to progressive migration of those elements, which are frequently used in plant protection especially in organic viticulture [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF]. The gradients of nutrients K, Zn and P come more likely from the uptake at depth by the plants and deposition through litter fall [START_REF] Jobbagy | The distribution of soil nutrients with depth: Global patterns and the imprint of plants[END_REF]. The fact that Mn, Fe, Sr, Mo and Ba are more concentrated in soils from the B catena is related to their higher abundance in the basaltic bedrock.

On the mixing diagram (Figure 6), leaves from different catenas display different 87 Sr/ 86 Sr values. Leaves from the B catena have values that are significantly lower than tufa and limestone rock indicating an influence of basalts on their Sr-uptake and thus on Ca-nutrition as Sr is considered as an analog of Ca, interchangeable in plant growth [START_REF] Walsh | The Effect on Plant Growth of Substituting Strontium for Calcium in Acid Soils[END_REF]. Plants from C catena all have Sr isotope ratios in the range of tufa or limestone. Leaves from C155 and C220 also have higher Ca/Sr ratios than the leaves from the B catena. This shows that, even in a context where plants are influenced to different degrees by the same rock formation, the geological origin of their nutrition can be traced using alkaline earth elements.

Among the vine leaf samples, Cu contents are high (from 34 to 125 mg kg -1 ) in comparison with the literature [START_REF] Ko | Mobility of copper, chromium and arsenic from treated timber into grapevines[END_REF][START_REF] Chopin | Factors affecting distribution and mobility of trace elements (Cu, Pb, Zn) in a perennial grapevine (Vitis vinifera, L.) in the champagne region of France[END_REF] and large variations are observed. These variations cannot be explained by variable soil Cu contents. The highest leaf Cu contents are measured in the upslope sampling sites. Nevertheless, a clear link between Cu concentration and Cu isotope ratios is observed: the higher the leaf content of Cu, the lighter the Cu isotopic composition (Figure 7). Isotopic ratios are much lighter in leaves (-0.9 to -1.8‰) than in soils or pesticides (-0.49 to 0.89‰) reported in [START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF]. As a consequence, incomplete washing can be excluded as a source of the high Cu contents.

This points towards a control of Cu content and isotopic ratios by physiological processes. [START_REF] Weinstein | Isotopic fractionation of Cu in plants[END_REF] suggested that the translocation of Cu to higher plant organs induce light isotope fractionation.

In this study, an equation linking the leaf height (from the soil) to the isotope ratios was proposed. This equation predicts surprisingly well (calculated δ 65 Cu = -1.57‰) the isotope ratios measured in the fieldgrown grapevines (-0.9 to -1.8‰). However, isotope fractionation within plants is still under discussion. [START_REF] Jouvin | Stable Isotopes of Cu and Zn in Higher Plants: Evidence for Cu Reduction at the Root Surface and Two Conceptual Models for Isotopic Fractionation Processes[END_REF] reported that light Cu was taken up from a nutrient solution and light Cu isotopes become further enriched in aerial parts of the plants. On the contrary, another study reported uptake of light Cu to roots and subsequent heavy Cu enrichment in aerial parts [START_REF] Ryan | Copper speciation and isotopic fractionation in plants: uptake and translocation mechanisms[END_REF]. The last study used extreme conditions with high doses of ionic Cu likely not occurring in nature. Light isotope enrichment with height has also been reported for the chemically similar element Zn (see Caldelas and Weiss, 2017 for a review and discussion of potential mechanisms). For Zn it was also reported that transpiration flow controls root to shoot Zn fractionation on contaminated soils [START_REF] Couder | Transpiration flow controls Zn transport in Brassica napus and Lolium multiflorum under toxic levels as evidenced from isotopic fractionation[END_REF].

However similar water supply and exposition rule out such influence in our setting. The gradient of Cu isotope ratios together with high Cu concentration points towards an immobilization mechanism of Cu in leaves (Blotevogel et al., 2016). The immobilization of Cu as Cu(I)-S groups favors light isotope enrichment in leaves and could thus explain our observations [START_REF] Collin | Evidence of sulfur-bound reduced copper in bamboo exposed to high silicon and copper concentrations[END_REF][START_REF] Ehlken | Environmental processes affecting plant root uptake of radioactive trace elements and variability of transfer factor data: a review[END_REF][START_REF] Jouvin | Stable Isotopes of Cu and Zn in Higher Plants: Evidence for Cu Reduction at the Root Surface and Two Conceptual Models for Isotopic Fractionation Processes[END_REF][START_REF] Mathur | Cu isotopic fractionation in the supergene environment with and without bacteria[END_REF][START_REF] Zhu | Mass fractionation processes of transition metal isotopes[END_REF].

Finally, small but significant differences in plant nutrition have been detected for various elements including some essential nutrients. It is difficult to directly link these differences to differences in soil chemistry. Yet it has been established that differences in bioavailability in elements can induce different elemental contents in plant tissues [START_REF] Kuppusamy | Does long-term application of fertilizers enhance the micronutrient density in soil and crop?-Evidence from a field trial conducted on a 47-year-old rice paddy[END_REF][START_REF] Tyler | Plant uptake of major and minor mineral elements as influenced by soil acidity and liming[END_REF]. Note that, these differences do not necessarily include the element whose availability changed. That effect is on one hand due to plant homeostasis mechanisms that can keep tissue concentration especially of essential nutrients constant for a wide range of availability (Marschner and Marschner, 2012); on the other hand regulation mechanisms of plants are not totally independent and exclusive for one element, so that chemically similar elements can be taken up "passively along the way" [START_REF] Ehlken | Environmental processes affecting plant root uptake of radioactive trace elements and variability of transfer factor data: a review[END_REF][START_REF] Tyler | Ionic charge, radius, and potential control root/soil concentration ratios of fifty cationic elements in the organic horizon of a beech (Fagus sylvatica) forest podzol[END_REF]. However, as factors other than soil chemistry are comparable between the two plots, we attribute detected differences to differences in soil chemistry.

In leaves, significant differences between the two plots were detected for the essential nutrients S, K and Zn. Note that higher concentrations were measured in plants grown on the C catena with more calcareous soils. No clear link can be drawn from leaf content to wine properties, still different tissue content of essential nutrients can have an impact on plant biosynthesis (Marschner and Marschner, 2012). In grapes, significant differences include concentrations and ratios of K and Ca, elements known for their role in wine acidity and polyphenol synthesis [START_REF] Brunetto | THE ROLE OF MINERAL NUTRITION ON YIELDS AND FRUIT QUALITY IN GRAPEVINE, PEAR AND APPLE[END_REF][START_REF] Daudt | Efeito do ácido tartárico nos valores de potássio, acidez titulável e pH durante a vinificação de uvas Cabernet Sauvignon[END_REF].

Potassium was more concentrated in grapes from the C catena whereas Ca was more concentrated in the B catena, highlighting the difference in the ratio between both elements (Table 3), which is particularly important for wine acidity [START_REF] Brunetto | THE ROLE OF MINERAL NUTRITION ON YIELDS AND FRUIT QUALITY IN GRAPEVINE, PEAR AND APPLE[END_REF][START_REF] Daudt | Efeito do ácido tartárico nos valores de potássio, acidez titulável e pH durante a vinificação de uvas Cabernet Sauvignon[END_REF]. It is interesting to note that lower Ca concentrations were detected in grapes grown on soils with higher Ca content. This observation highlights the regulation mechanisms carried out by plant during mineral nutrition, and especially during element uptake from soil. But it also puts in evidence the distinct role of sink and source organs [START_REF] Joubert | A case study of source-sink relationships using shoot girdling and berry classification (Vitis vinifera cv. Cabernet Sauvignon[END_REF] during element translocation from the roots to the different shoots compartments (leaves or grapes). Finally, via the uptake of elements and then their translocation through the plant, this study highlights possible pathways of the influence of soil chemistry on wine properties.

Conclusion

In the two examined Soave plots, pedologic differences are obvious from field observations. However, complex formation processes and interlayering of the different bedrocks resulted in rather homogenous chemical composition of soils. This shows that soils that appear to be morphologically different can have similar chemical functioning in terms of element mobility, retention and bioavailability.

The pedogenetic processes and the mechanisms involved in mineral nutrition in the Soave vineyard have then been investigated through the elemental contents in the soil-to-grape continuum and the isotope ratios for Cu and Sr. In the Soave vineyard, similar soil chemistry is reflected by similar elemental concentrations in grapevine leaves, although there appears to be a trend for higher elemental concentration in plants grown on more calcareous soil. Moreover, elements are finally not identically distributed in the plants form the two catena and along the different plant tissues (especially leaves or grapes) implying different regulation mechanisms during the soil-to-grape continuum, through uptake and translocation processes. Most importantly K and Ca contents and their ratio, known for regulating wine acidity, vary significantly between the two plots.

Isotope ratios measurements show that radiogenic Sr isotopes compositions can be used as a tracer of the geological origin of grapevine nutrition, whereas Cu isotope ratios rather depend on plant regulation mechanisms.

Finally, as methods presented in this paper give first indications on the role of soil chemistry in the potential "terroir effect", it would be possible to go further by improving the sampling strategy (more contrasted soils with a higher number of sampling points, sampling tissues at different vine growth stages, and over several years). However, attention must be given to the other "terroir" components as meteorological parameters, agricultural practices management in the field, winemaking process, etc. in order to more isolate the soil influence.

  nutrients and pollutants.According to our dataset, the soils of the two catenas are clearly dissimilar after field pedological description in terms of morpho-pedological features. Color, structure and inorganic carbon content show distinct features of the two soil types. There is a tendency for more massive or prismatic structures associated with shrink swell-crack features in the B catena (depending on water content) and more polyhedral to single grained structures in the C catena. Furthermore, soils of the C catena show important calcic properties with calcic horizons lighter in color and in secondary carbonates contents, and all cambic calcisol horizons show traces to large amounts of calcite in XRD spectra. Even if secondary calcite phases are found in soils from the B catena, the studied Vertic Cambisols clearly have minerals inherited from basalt, have greater amount of clay fraction and display vertic properties (shrink swell cracking, wedge shapes aggregates, slickensides type features). Besides, soils from the C catena tend to have higher sand contents even after elimination of carbonates. However, a more detailed look also shows similarities. There are several calcic horizons in the upslope soils of the B catena and CEC values are similar in all soils; only C220 shows lower CEC values than the other soils and pH values are >7 in all

FiguresFigure 1 -

 1 Figures

Figure 2 -

 2 Figure 2 -Schematic illustration of the field observations for the soils of the two catenas investigated in the present study (B & C). Roots are particularly thick in the first 10-20 cm forall the sampling points. Soil profile description was stopped according to the soil depth, using an Edelman soil corer down to the depth of 120 cm maximum. Soil structures above 50 cm are indicative structures as structure observation is biased during soil corer sampling.

Figure 3 -

 3 Figure 3 -Elevation and slope direction map of the studied vineyard plots.The aerial image is taken from Google Earth®.

Figure 4 -Figure 5 -Figure 6 -

 456 Figure 4 -XRD spectra of rocks and soil horizons (a-Basalt rock and B catena; b-Calcareous rock and C catena). For clarity, only the main peaks of the identified phases are reported for silicates (a).

Figure 7 -

 7 Figure 7 -Cu isotope ratios in vine leaves as a function of their Cu-content.

pedological description and soil identification

  Studied soil profiles from the C catena feature granular to fine subangular blocky soil structure with worm casts on top of the soil profile (i.e., A horizon, 0-10 cm). The structure evolves to blocky angular in intermediate calcic horizons, whereas the deepest calcic soil horizons seems to display single grained structure for C220 and powder-like structure in C155 (soil structure estimate using soil corer). Only C60 displays a more massive/prismatic structure in subsoil horizons. The texture is loamy clayey on topsoils and gets coarser towards the bottom. Soil colors are mostly 10 YR 4/3 but the lowest horizon of C220 displays 10 YR 5/3 colors. All studied soil profiles from the C catena present an increase in carbonate

	%&'()*+, 2	. /0 ' = 1	/0 /0	' '	/ /	' '	23 456/	-17 * 1000
	Results
	Field morpho-

Our measured values (0.21 ± 0.03 ‰) are in line with formerly published values of 0.20 ± 0.10 ‰

[START_REF] Babcsányi | Distribution of organic carbon and lignin in soils in a subtropical small mountainous river basin[END_REF]

and 0.22 ± 0.05 ‰

(Bigalke et al., 2010a)

.

Purified solutions were spiked with IRMM Zn standard for measurements on MC-ICP-MS (Nu Plasma 500, Nu Instruments® at ENS in Lyon; Neptune plus, Thermo Finnigan® at GET in Toulouse). Exponential laws were used to correct for mass bias using 66/64, 68/64 and 68/66 Zn isotope ratios (see

[START_REF] Maréchal | High-Precision 87Sr/86Sr Analyses in Wines and Their Use as a Geological Fingerprint for Tracing Geographic Provenance[END_REF]

and

[START_REF] Blotevogel | The fate of Cu pesticides in vineyard soils: A case study using δ 65 Cu isotope ratios and EPR analysis[END_REF]

for more details). Cu isotope ratios are expressed in ‰ relative to NIST 976 Cu standard, according to the Equation (2): content with depth, as indicated by their reaction with 1 M HCl. The increase in carbonate phase content with depth is due to two main processes: i) primary carbonate dissolution in surface horizons; and ii) secondary carbonate formation in subsoil. The soils from the C catena were identified as Cambic Calcisols (according to the World Reference Base for soil resources from FAO/ISRIC/ISSS, 2014), as described in Figure

2

.

Table 1 -

 1 Mineralogical and physico-chemical properties of Soave soils

	Soil ID and depths (cm)	Horizon (WRB classification)	Mineralogical phases	pH (H 2 0)	CEC	SIC	SOC	Clay	Silt Sand	K
					cmol/kg wt %	wt %	wt %	wt %	wt %	m.s	-1
	B20										1*10 -5
	0-10	Mollic, calcic calc., felds., smec.	7.51	72.12	1.8	4.3	30		3
	10-30	Calcic	calc., felds., smec.	7.67	66.13	2.2	1.3	39		2
	50-70	Vertic	felds., smec.	7.80	71.91	0.5	0.7	25		5
	70-120	Vertic	felds., smec.	7.74	75.23	<0.1	0.8	34		2
	B60										2*10 -6
	0-10	Mollic	felds., smec.	7.17	82.94	0.5	7.1	38		1
	10-30	Cambic	felds., smec.	7.90	NA	0.4	1.3	42		1
	30-60	Vertic	felds., smec.	7.83	77.72	0.3	0.9	33		1
	60-70	Vertic	qtz., felds., smec.	7.82	78.31	0.3	0.6	36		3
	70-90	Calcic	calc., felds., smec.	7.87	82.75	1.6	<0.1	15		20
	B150										8*10 -7
	0-10	Mollic	felds., smec.	7.29	80.16	0.2	3.9	55		0
	10-40	Cambic	felds., smec.	NA	NA	0.3	NA	50		0
	40-50	Vertic	felds., smec.	7.60	78.87	0.1	0.9	52		0
	50-70	Vertic	felds., smec.	NA	NA	0.1	NA	55		0
	70-90	Vertic	felds., smec.	7.82	69.97	0.2	1.3	54		0
	90-100	Vertic	felds., smec.	7.76	72.25	0.6	0.0	55		0
	C60										1*10 -5
	0-10	Mollic, calcic qtz., calc., felds.	7.24	80.36	0.5	4.9	63		0
	10-30	Calcic	qtz., calc., felds.	7.67	77.87	0.6	1.3	32		4
	30-50	Cambic	qtz., calc., felds.	7.62	84.55	0.8	0.9	31		0
	50-70	Cambic	calc., qtz., felds.	7.79	79.61	1.9	<0.1	40		0
	C155										3*10 -5
	0-10	Mollic,	calc., felds., smec.	7.32	83.01	1.4	2.0	32		5
	10-50	Cambic	calc., felds., smec.	7.59	79.49	1.5	0.9	31		8
	50-70	Calcic	calc., felds., smec.	7.84	80.99	2.1	0.2	33		11
	70-100	calcic	calc., felds., smec.	7.91	82.63	1.9	<0.1	10		8
	C220										7*10 -5
	0-10	Mollic, calcic calc., felds., smec.	7.24	65.97	3.7	4.9	24		11
	20-50	Calcic	calc., felds., smec.	7.90	55.12	4.9	0.5	28		20
	50-60	Calcic	calc., felds., smec.	8.14	50.80	5.6	0.2	NA	NA	NA

Table 2 -

 2 Elemental contents (expressed in g kg -1 or mg kg -1 ) and Sr isotope ratios in soil and rock samples. P-values of one-sided Mann Whitney U-test (MWU-test) between all horizons of the two catenas were performed to evidence significant differences. Differences are considered significant if p ≤ 0.05 and are annotated with a*.

		Type Depth Mg	Al	P	K	Ca	Mn	Fe	S	Cu	Zn	Sr	Mo	Ba	87 Sr/ 86 Sr	2SD
				g kg -1 g kg -1	g kg -1	g kg -1 g kg -1 g kg -1 g kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1
	B20	Bulksoil 0-10	19.36 56.28 2.85 7.10 86.35	1.00 62.08	679 356.6 162	257	1.02	0.7056 0.00011
	B20	Bulksoil 10-50 20.37 56.12 2.24 5.90 107.34 1.02 66.83	317 209.6 138	295	1.03	-	-
	B20	Bulksoil 50-70 12.52 36.96 1.75 4.05 40.82	1.08 75.40	-	91.0 125	256	0.94	0.7047 0.0001
	B20	Bulksoil	110-120	10.90 57.53 1.03 4.23 23.34	1.35 84.36	76	63.6 118	179	0.57	0.7051 0.00008
	B60	Bulksoil 0-10	15.83 49.21 3.36 7.17 42.37	1.18 66.74	965 563.7 196	221	1.36	0.7054 0.00011
	B60	Bulksoil 10-30 17.71 61.77 1.78 4.12 39.62	1.16 72.27	-	135.9 115	193	1.06	-	-
	B60	Bulksoil 30-60 11.70 54.29 1.57 4.45 32.68	1.33 77.28	177 79.9 112	188	0.90	0.7057 0.00013
	B60	Bulksoil 60-70 15.55 51.80 1.79 6.25 31.78	1.15 82.37	-	56.7 112	176	2.69	-	-
	B60	Bulksoil 70-90 33.04 50.89 4.17 2.39 95.64	0.97 77.08	-	40.3 101	406	1.17	0.7053 0.00013
	B150	Bulksoil 0-10	7.93 36.57 3.34 8.76 31.16	1.08 71.77	547 277.0 163	250	1.40	0.7043 0.00011
	B150	Bulksoil 40-50 8.62 46.07 2.42 6.09 27.82	1.27 83.35	155 72.8 140	217	1.25	0.7043 0.00011
	B150	Bulksoil 70-90 18.22 61.35 2.88 7.48 45.06	1.20 93.37	-	61.0 139	420	1.34	-	-
	B150	Bulksoil	90-100	17.95 70.39 3.05 7.92 52.64	1.32 98.88	-	59.1 133	441	1.46	0.7037 0.00009

Table 3 -

 3 Elemental contents (expressed in g kg -1 or mg kg -1 ) in leaves and grapes, and C, Sr and Cu isotope ratios in leaves. P-values of onesided Mann Whitney U-test (MWU-test) between the two catenas were performed to evidence significant differences between the two plots. Differences are considered significant if p ≤ 0.05 and are annotated with a*.

	Sampl e	Type N Mg P	S	K	Ca	Al	Mn	Fe	Cu	Zn	Sr	Mo	Ba	K/C a	δ 13 C	2S D	87Sr/8 6Sr	2SD	δ 65 C u	2S D
			g kg -1	g kg -1	g kg -1	g kg -1	g kg -1	g kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mg kg -1	mol mol -1	‰ ‰		‰	‰
	B20	Leaf	13. 04	2.8 1	2.2 4	1.6 3	6.8 5	29. 7	24.4 35.7 33 99.3 18.4 49.9	0.11 8	8.79	0.2 4	-26.5 6	0. 22	0.7065	0.00 008	-1.73 5	0.0 98
	B60	Leaf	12. 77	2.9 5	2.5 3	1.4 1	7.0 5	31. 7	25.3 23 34.4 70.5 24.1 66.3	0.03 6	8.34	0.2 3	-27.6 4	0. 12	0.7061	0.00 012	-1.28	0.1
	B150	Leaf	15. 14	4.2 4	2.3 9	1.4 4	4.6 7	32. 1	27.1 51.9 44.3 43.6 23.2 54.2	0.04 2	18.4 1	0.1 5	-26.3 0	0. 24	0.7062	0.00 01	-7 1.06	0.1
	C60	Leaf	14. 03	3.1 5	2.1 4	1.7 8	8.4	26. 9	29.9 49.6 64.2	125. 4	25.6 43.1	0.27 1	36.1 4	0.3 2	-26.5 4	0. 33	0.7072	0.00 009	-1.83 3	0.0 55
	C155	Leaf	15. 00	5.4 9	4.0 8	1.6 7	7.3 2	37. 7	25.3 58.8 40.6 33.9 35.2 48.7	0.16 6	22.6 5	0.2 0	-26.9 6	0. 05	0.7068	0.00 012	-0.86 3	0.1 02
	C220	Leaf	15. 80	2.7 4	2.7 7	1.6	9.0 4	32. 6	40.7 47.9 45.7 74.3 28.8 38.6	0.11 4	20.4 2	0.2 9	-27.0 2	0. 05	0.707	0.00 013	-1.13 4	0.0 09
	MWU-test	p-valu e	0.2 0	0.5 0	0.3 5	0.1 0	0.0 5*	0.3 5	0.13 0.20 0.10 0.50	0.05 *	0.05 *	0.10	0.05 *	0.2 0	0.50		0.05*	0.50
	B20	Grap e	3.3 3	0.7 2	1.3 7		9.2 1	2.3 7	4.80 2.90 8.11 5.83 5.05 5.38	0.02 8	1.15	9 3.9	24.5 -	0.

Acknowledgments

The authors would like to thank the French INSU national program EC2CO (BIOEFFECT) for its financial help in the TERVIT program. We also want to express our gratitude to Rémi Freydier from AETE-ISO "Analyse des Eléments en Trace dans l'Environnement & ISOtopes" Technical Platform, Philippe Telouk from ENS Lyon and Issam Moussa from the SHIVA platform in Toulouse, for their precious help in elemental contents and isotopes analyses. Finally, we would like to address a very special thanks to Filippo Filippi, the Italian wine grower and winemarker for providing us technical information, allowing us to collect samples in his vineyard and for his kindly and warm welcome in Castelcerino (Soave, Italy).