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IVES 9 IVES Conference Series 9 Caractérisation des relations hydriques sol/vigne dans un terroir languedocien

Caractérisation des relations hydriques sol/vigne dans un terroir languedocien

Abstract

Par le fait d’une politique agricole communautaire axée sur des objectifs de qualité des produits, la recherche et l’identification des critères de cette qualité deviennent impératives. En viticulture, la notion de qualité du produit est rattachée au concept théorique de «terroir». Ce terme englobe un ensemble de paramètres du milieu (géologie, sol, climat) influant sur la récolte.

L’objectif du travail présenté est de déterminer une relation entre la consommation en eau d’une parcelle de vigne et l’état hydrique du sol. Cette relation doit ensuite pouvoir être transposée dans des situations pédoclimatiques variées. Cette étude fait partie d’un programme de recherche d’étude des flux d’eau et de polluants à l’échelle d’un bassin versant viticole méditerranéen (programme Allegro-Roujan).

L’alimentation en eau des ceps a une influence reconnue sur les caractéristiques gustatives des raisins et des vins. Or, on sait que la quantité d’eau absorbée est en relation avec les conditions d’humidité de l’air (Diuing, 1987) et du sol (nombreuses études dont Smart, 1974 ; Daudet et Katerji, 1986). Cependant, ces relations sont complexes puiqu’elles dépendent du cépage (Winkel et Rambal, 1993) et, de ce fait, sont mal connues.

La caratérisation de l’extraction racinaire de la vigne in situ pose de nombreuses difficultés expérimentales. Celles-ci sont liées à :
(1) la profondeur d’enracinement de la vigne ;
(2) la discontinuité du couvert pouvant engendrer des discontinuités d’enracinement ;
(3) le faible maillage de colonisation racinaire associé aux faibles besoins en eau de la vigne qui induit une forte incertitude en raison de la faible représentativité parcellaire des mesures locales de variation d’humidité du sol.

De ce fait, à notre connaissance, les travaux publiés ne permettent pas de relier de manière sûre la consommation en eau d’une vigne avec l’état hydrique du milieu, élément intrinsèque à la notion de terroir.

Dans le travail présenté, l’effort a été mis sur une caractérisation expérimentale de l’alimentation en eau de la vigne sur une parcelle unique. Les buts sont de parvenir à une estimation de l’ETR parcellaire la plus fiable possible et de la mettre en relation avec l’humidité du sol dans un second temps.

DOI:

Publication date: March 25, 2022

Issue: Terroir 1996

Type: Poster

Authors

W. TRAMBOUZE, M. VOLTZ

I.N.R.A. centre de Montpellier Laboratoire de Sciences du sol, 2 Place Viala, 34060 Montpellier Cedex 01

Tags

IVES Conference Series | Terroir 1996

Citation

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