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IVES 9 IVES Conference Series 9 Methodology for soil study and zoning

Methodology for soil study and zoning

Abstract

La caractérisation des sols en vue d’une étude de terroirs viticoles peut être réalisée à différents niveaux de complexité, suivant le nombre de variables pris en compte et suivant le fait que celles-ci sont spatialisées ou non. La cartographie des sols est une approche très complète, notamment lorsqu’elle s’appuie sur des cartes géologiques et géomorphologiques réalisées au préalable. Néanmoins, même si elle est très détaillée, la caractérisation des sols reste par définition descriptive. Pour expliquer le lien entre le terroir, la qualité des vins et leur typicité, il faut prendre en compte les interactions qui existent entre la vigne et son environnement (sol et climat): c’est le domaine de l’écophysiologie. Les études écophysiologiques sont pluridisciplinaires et ont le défaut d’être lourdes à mettre en œuvre. Plusieurs équipes ont proposé des méthodologies pour alléger les études de sol. Lorsqu’on doit réaliser une étude sur une grande surface, on peut réaliser au préalable une cartographie à grande échelle sur un secteur de référence pour établir des lois de distribution des sols. Etant donné l’importance de la profondeur du sol sur le fonctionnement de la vigne, un modèle roche-altération-altérite a été proposé. La télédétection peut alléger le travail à réaliser sur le terrain et permettre de cartographier des pédo-paysages. Des indicateurs physiologiques peuvent renseigner sur l’état nutritionnel de la vigne (eau et éléments minéraux), en relation avec l’offre du sol. Ces indicateurs permettent de générer différentes couches d’information sur le fonctionnement de la vigne, qui peuvent être complétées par de l’information concernant le sol et la qualité des raisins et valorisées à travers le concept de la viticulture de précision. Ceci aboutira à terme à de véritables études écophysiologiques spatialisées.

Soil is an important factor of “terroir”. Soil studies can be more or less complex depending on the number of variables taken into account and depending on whether they are spatialized or not. Soil mapping, carried out after preliminary geological and geomorphological studies, is an interesting approach. Nevertheless, the interactions between the soil, the climate and the vine have to be taken into account by means of an ecophysiological approach to explain how “terroir” acts on vine behaviour, wine quality and wine style. Because “terroir” studies are very time consuming and therefore expensive, several lightened methodologies have been developed. When the soils of a large area have to be mapped at a small scale, a small representative reference sector can be mapped previously at a large scale. The reference sector will provide soil distribution laws that can be applied to the large area. To simplify the soil mapping, soils can be grouped depending on their depth, which is a determining factor in water and nutrient supply to the vines. Remote sensing can help to reduce soil sampling density. Physiological indicators can be used to assess vine water and nitrogen supply, in relation to the soil type. Several layers of information about the soil, the vine development and berry constitution can be related in a Geographical Information System (G.I.S.). Precision viticulture is the application of this technique to asses variability inside a plot of vines. Although it is still a relatively new approach, it is a powerful tool that can provide a spatialized ecophysiological approach of “terroir”.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

C. VAN LEEUWEN (1, 2), Ph. CHERY(1), J.-Ph. ROBY (1), D. PERNET (1), J.-P. GOUTOULY (3) and J.-P. GAUDILLERE (3)

(1) ENITA de Bordeaux, 1 Crs du Général de Gaulle, BP 201, 33175 Gradignan-Cedex, France
(2) Faculté d’Œnologie, 351 Crs de la Libération, 33405 Talence-Cedex, France
(3) INRA-Agronomie, BP 81, 33883 Villenave d’Omon, France

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Keywords

terroir, sol, zonage, cartographie, vigne, régime hydrique, télédétection, viticulture de précision, indicateurs physiologiques, secteur de référence, Système d’information Géographique (S.I.G.)

terroir, soil, zoning, mapping, vine, water status, remote sensing, precision viticulture, physiological indicators, reference sector, Geographical Information System (G.I.S.)

Tags

IVES Conference Series | Terroir 2002

Citation

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