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IVES 9 IVES Conference Series 9 Variability in the content of coarse elements in a viticultural plot in the Graves appellation: relationship with geophysical data

Variability in the content of coarse elements in a viticultural plot in the Graves appellation: relationship with geophysical data

Abstract

Il a été souvent démontré (Seguin, 1970), que les meilleurs terroirs sont ceux qui présentent pendant la période de maturation du raisin, une régulation et une limitation de l’alimentation hydrique de la vigne. Si on s’intéresse aux facteurs influençant ce régime hydrique, on constate le rôle prépondérant du taux d’éléments grossiers non poreux qui limitent la réserve utile du sol en diminuant le taux de terre fine. De plus, ces éléments grossiers jouent également un rôle au niveau du pédo-climat thermique car leur conductivité thermique et leur chaleur spécifique sont plus élevées que celles de la terre fine. Ainsi le sol se réchauffera et se refroidira plus rapidement (Saini et McLean, 1967), (Gras, 1994). Dans le cadre d’une viticulture de précision, la réalisation de cartes de teneur en éléments grossiers peut conduire à une meilleure compréhension de l’alimentation hydrique de la vigne. Cependant, ce genre de cartes est très exigeant en terme de densité de données à acquérir, afin d’obtenir une précision suffisante pour décrire la variabilité du milieu étudié et faciliter ainsi la maîtrise de l’itinéraire technique par le viticulteur.
Les récentes avancées technologiques en géophysique pourraient permettre de contourner cette difficulté. Il est possible d’utiliser des variables de natures différentes des variables pédologiques comme les mesures de résistivité électrique. Elles sont en général sur-échantillonnées et peuvent être acquises par des méthodes automatisées. Mais elles sont aussi plus intégratrices et peuvent donc entraîner un lissage des variations ponctuelles. Ce travail a pour but d’établir une relation entre la teneur en éléments grossiers de surface à des mesures de résistivité électrique sur sol de graves. Le but de l’étude est de pouvoir réaliser à partir de ces mesures de résistivité, une cartographie précise du taux d’éléments grossiers (EG) pour évaluer les potentialités viticoles des parcelles.

DOI:

Publication date: December 22, 2021

Issue: Terroir 2006

Type: Article

Authors

P. CHÉRY (1), M. CHRISTEN (1), M. DABAS (2), M. JULLIOT (1) et G. GRENIER (1)

(1) École Nationale d’Ingénieur des Travaux Agricoles de Bordeaux, Laboratoire sols et paysages, 1 cours du Général de Gaulle, B.P. 201, 33175 Gradignan cedex, France
(2) GÉOCARTA, 7, place de la Nation 75012 Paris, France

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IVES Conference Series | Terroir 2006

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