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IVES 9 IVES Conference Series 9 Apports des mesures de résistivité électrique du sol dans les études sur le fonctionnement de la vigne et dans la spatialisation parcellaire

Apports des mesures de résistivité électrique du sol dans les études sur le fonctionnement de la vigne et dans la spatialisation parcellaire

Abstract

[English version below]

La mesure de la résistivité électrique des sols est une technique non destructive, spatialement intégrante, utilisée depuis peu en viticulture. L’utilisation d’appareils de mesures performant et de logiciels adaptés permet de traiter les données afin de pouvoir visualiser en deux ou trois dimensions les variations de textures ou d’humidité d’un sol.
La résistivimétrie électrique est testée depuis deux ans à l’Unité Vigne et Vin du Centre INRA d’Angers pour étudier l’alimentation hydrique de la vigne. Les techniques classiques qui permettent de mesurer quantitativement l’état hydrique du sol sont trop peu représentatives du volume de sol réellement prospecté par les racines. Les mesures de résistivité électrique autorisent en revanche une spatialisation précise des zones d’activités racinaires préférentielles, le volume de sol soumis au prélèvement des racines peut ainsi être mieux appréhendé. Cette technique permet une visualisation des zones de dessèchement préférentiel, et pour certains types de sols, elle permet également de quantifier l’eau disponible. Il est également possible de visualiser en temps réel les effets d’une pluie ou d’une sécheresse au travers de la sollicitation des racines ainsi que d’appréhender les effets de l’enherbement ou de différents porte-greffes sur l’alimentation hydrique de la vigne.
La résistivimétrie électrique peut également être appliquée en viticulture de précision puisqu’elle permet d’affiner la cartographie pédologique d’une parcelle. Le choix de l’emplacement de fosses pédologiques ou la localisation des différents porte-greffes pour la plantation peuvent être des applications directes de cette cartographie géophysique.
L’utilisation des techniques de géophysiques telles que la résistivimétrie électrique du sol peut donc aussi bien servir la recherche que devenir un outil de spatialisation pour la viticulture de précision, d’autant plus que les avancées technologiques récentes dans ce domaine permettent désormais une utilisation plus aisée des différents appareils de mesure.

The measurement of soil electric resistivity, as a non destructive, spatially integrative technique, has recently been introduced into viticulture. The use of performing equipment and adapted software allows for rapid data processing and gives the possibility to visualise the variations of soil texture or humidity in two or three dimensions.
Soil electric resistivity has been tested for the last two years at the Experimental Unit on Grapevine and Vine, INRA, Angers, France, to study the water supply to the vine in different “terroir” conditions. The classical techniques that allow to quantify the soil water status do not give access to the volume of soil explored by the root system. On the contrary, measurements of soil electric resistivity permit to visualise precisely the zones of preferential grapevine root activity. In some types of soil, available water may even be quantified. It is also possible to monitor in real time the effects of rain or drought through root solicitation, as well as the effects of soil management (inter-row grassing) or different rootstocks on the water supply to the vine.
When applied to precision viticulture, electric resistivity can be used to refine the geo-pedological cartography of a given plot. The choice of sites for pedological studies or the assistance for selection of rootstocks are direct applications of this cartography.
The use of geophysical techniques such as soil electric resistivity constitutes a tool for the use of both scientists and adepts of precision viticulture. Recent technological developments are now facilitating the use of these equipments.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

E. Goulet (1) et G. Barbeau (2)

(1) Cellule « Terroirs Viticoles », Confédération des Vignerons du Val de Loire, 42 rue Georges Morel, 49071 Beaucouzé Cedex
(2) Unité Vigne et Vin, INRA, 42 rue Georges Morel, 49071 Beaucouzé Cedex

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Keywords

Vigne, sol, résistivité électrique, alimentation hydrique, spatialisation 
grapevine, soil, electric resistivity, water supply, spatial land distribution 

Tags

IVES Conference Series | Terroir 2004

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