Terroir 2008 banner
IVES 9 IVES Conference Series 9 Contribution of Electrical Resistivity Tomography (ERT) measurements for characterizing hydrological behaviour of an experimental plot in relation to pedo-geological factors (AOC Gaillac, SW France)

Contribution of Electrical Resistivity Tomography (ERT) measurements for characterizing hydrological behaviour of an experimental plot in relation to pedo-geological factors (AOC Gaillac, SW France)

Abstract

Electrical Resistivity Tomography (ERT) measurements have been performed by the Wenner method on an experimental plot situated in Gaillac region. They have been carried out during two highly contrasted hydric periods: (i) dry (spring 2006), (ii) humid (spring 2007) with soils close to field capacity. Results are compared to evaluate the hydrological behavior of the plot in relation with its main pedo-geological characteristics. The three reiterated transects (North-Median-South) give a general view of the plot configuration in agreement with the pedo-geologic observation trenches data. All the resistivity profiles show the superposition of two highly contrasted sequences. The first sequence, at the bottom, is a very low resistivity values sequence (up to 40 Ω.m) which coincides with the argillaceous-dominated molassic bed-rock. The second is a high to very high resistivity values sequence (from 300 Ω.m to more than 1500 Ω.m at the very top) which coincides with a silty-sandy and gravels soil complex of about 2 m thick. Resistivity of the molassic clayed-dominated geological basement does not depend on climatic conditions and stays at a very low value independently of dry or humid periods. Resistivity values of the silty-sandy/gravels horizons vary with a factor 2, from 300 to 750 Ω.m in humid conditions and from 750 Ω.m to 1500 Ω.m under dry conditions. Furthermore, the invariant location in the resistivity profiles of the two sequences, implies that the water runoff at the molassic bed rock/gravels interface is short-lived and most probably of low amplitude.
The hydric behavior of the experimental plot evidences a high risk of drought stress during summer. The choice of a rootstock with a hemi-plunging habit (Gravesac) will allow roots to attain the moisture at the molasse/gravels boundary and protect them from excess of drought.

DOI:

Publication date: December 8, 2021

Issue: Terroir 2008

Type : Article

Authors

Pierre COURJAULT-RADÉ (1), José DARROZES (1), Muriel LLUBES (2), Eric MAIRE (1), Marguerite MUNOZ (1) and Nicolas HIRISSOU (3)

(1) Laboratoire des Mécanismes de Transfert en Géologie (LMTG) – Université de Toulouse – UMR 5563 – CNRS – 14, Avenue E. Belin 31400 Toulouse (France)
(2) Laboratoire d’Etudes en Géophysique et Océanographie Spatiales (LEGOS)- Université de Toulouse – 14, Avenue E. Belin 31400 Toulouse (France)
(3) Domaine du Moulin, Chemin de Bastié, 81600 Gaillac (France)

Contact the author

Keywords

AOC Gaillac, Fonctionnement hydrique, Pédo-géologie, Résistivité, Sud-Ouest France

Tags

IVES Conference Series | Terroir 2008

Citation

Related articles…

Why aren’t farmers using precision viticulture frequently? A case study

n the last years, viticulture precision tools have been made available for farmers for different crops. The feeling that these tools are mandatory on an agriculture of the future have been disseminated by commercial entities but also from policy makers.

«Nektar» -the new red variety wine grape aromatic high quality

The multi-annual study of the International Genetic Bank of the Grape Vine has shown that red varieties are enough, but the red varieties that produce high-quality red wine are minimal.

Genotypic differences in early-stage root architectural traits and consequences for water uptake in three grapevine rootstocks differing in drought tolerance

Root architecture (RSA), the spatial-temporal arrangement of a root system in soil, is essential for edaphic resources acquisition by the plant, and thus contributes largely to its productivity and adaptation to environmental stresses, particularly soil water deficit. In grafted grapevine, while the degree of drought tolerance induced by the rootstock has been well documented in the vineyard, information about the underlying physiological processes, particularly at the root level, is scarce, due to the inherent difficulties in observing large root systems in situ. The aims of this study were (i) to determine the phenotypic differences in traits related to root distribution and morphology along the substrate profile in different Vitis rootstocks during early growth, (ii) to assess the plasticity of these traits to soil water deficit and (iii) to quantify their relationships with plant water uptake.

Isotope composition of wine as indicator of terroir spatial variability

The goal of this work was to determine the spatial variability of terroir using the isotope composition of wine. Carbon (δ13C) and oxygen (δ18O) stable isotope composition was measured in wines from Tempranillo (Vitis vinifera L.) vineyard, located in Rioja Appellation (Spain). Stable isotope composition, leaf area, vigour, yield components, grape and wine composition were determined in a grid of 85 geo-referenced points, that was drawn across the 5 ha vineyard area

A multilayer interactive web map of the wine growing region carnuntum with emphasis on geochemical and mineralogical zoning

During a three-year study the vineyards of the wine-growing region Carnuntum have been investigated for their terroir characteristics (climate, soil, rocks) and major viticulture functions. As an outcome of the study, various thematic layers and geodata analyses describe the geo-environmental properties and variability of the wine growing region and delimit homogenous multilayer mapping units by using a Geographic Information System.