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IVES 9 IVES Conference Series 9 A applied viticultural zoning, based on the “secteurs de la reference” methodology, in the Cognac vineyard (France)

A applied viticultural zoning, based on the “secteurs de la reference” methodology, in the Cognac vineyard (France)

Abstract

Dans les Charentes, en réponse à une crise de production du vignoble destiné à la production de Cognac, un plan de diversification viticole pour des vins de pays de qualité est mis en place. Il nécessite une connaissance des sols et de leurs caractéristiques viticoles pour orienter le choix des types de vins et adapter l’itinéraire technique de production.
Afin de permettre une caractérisation rapide de l’ensemble du vignoble avec des coûts d’investigations limités, des secteurs de références (aires-échantillon d’extension limitée mais représentatives) ont été choisis à l’aide des cartes pédologiques à l’échelle du 1/250 000, et précisés par des visites de terrain. Ces secteurs de référence ont fait l’objet d’une cartographie pédologique fine qui a permis de définir les différents types de sol et leur mode d’organisation spatiale. A partir d’observations détaillées et d’analyses effectuées sur des profils représentatifs de chaque type de sol, les potentialités et les contraintes agro-viticoles sont analysées selon une démarche collective associant chargés d’études pédologiques, techniciens locaux viticulteurs et experts viti-vinicoles. Cette analyse débouche sur des recommandations relatives au choix des cépages, porte-greffes et pratiques viticoles susceptibles d’exploiter au mieux la potentialité de chaque type de sol, considéré ici comme unité de terroir. L’extension des résultats à l’ensemble du vignoble est réalisée au moyen de cartes d’extrapolation associées à des clefs de détermination qui permettent en priorité au technicien viticole mais aussi au viticulteur d’identifier l’unité de sol de chaque parcelle et d’utiliser les recommandations relatives à celle-ci. L’ensemble des résultats obtenus est par ailleurs largement diffusé auprès de tous les acteurs de la filière selon des médias adaptés.
Après trois ans de travail sur cinq secteurs de référence, les résultats sont positifs et la méthode a fait les preuves de son efficacité. Cette approche de la notion de terroir est un élément fédérateur de tous les acteurs viticoles et un élément structurant permettant d’organiser l’acquisition progressive de références propres au vignoble concerné. Dans cette perspective, des réseaux de suivi s’installent. Par ailleurs, la caractérisation des terroirs sera complétée par des études climatiques.

The “Charentes” region wants to diversify its Cognac vineyard by growing quality wines. This inquires precise soil knowledges to advise the right rootstock, grape variety and vineyard management.
To study soils on a so wide area with a limited budget, several “secteurs de référence” (smallest sample-areas representing the major regional soil types) are located thanks to different soil maps on scale 1/250 000 and a technical field visit. Those “secteurs de référence” are surveyed in details to identify the different soil types and understand their spatial relationship. Each soil type is then characterized by soil profile observations and analysis which lead to lighten the main vine growing factors. A panel of experts in soil science, viticulture and enology, and local wine growers is then constituted to select the most suitable rootstock, grape-variety and vineyard management in each soil (fig.1). To generalize the results to a wider area, extrapolation maps of soil are established, and a key to identify each kind of soil is built (fig.2). That key is to be used by anyone to be able to recognize precisely a soil type thanks to several easy-to-use discriminating observations, and then to advise for planting. The results are published towards people involved in quality wine production on different adapted mass media and through meetings.
After three years of studies on five “secteurs de référence” in the Cognac region (tab.1), the results are very encouraging. This method is perfectly well adapted to characterize soils on wide areas. It involves people of different demains, and generates a human and technical dynamic. It is also very evolutive and allow, by structurating a general soil programm, to’ go step by step in a “terroir” approach. It is really the first stone of a wider zoning, including also bio-climatic studies, and has to be followed by experimental plots to give the most suitable advices for the future.

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DOI:

Publication date: February 16, 2022

Issue: Terroir 2002 

Type: Article

Authors

Catherine CAM*, Pierre VITAL**, Jean-Luc FORT*, Philippe LAGACHERIE***, René Morlat****

* Chambre Régionale d’Agriculture Poitou-Charentes
** Coopérative Agricole Syntéane, Saintes
*** UMR ENSAM-INRA Sols et Environnement, Montpellier
****Unité expérimentale Vigne et Vin, Centre INRA Angers

Keywords

vigne, Cognac, sol, secteur de référence, experts
vine, Cognac, soil, zoning, experts

Tags

IVES Conference Series | Terroir 2002

Citation

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