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IVES 9 IVES Conference Series 9 Caractéristiques physiques et agronomiques des principaux terroirs viticoles de l’Anjou (France). Conséquences pour la viticulture

Caractéristiques physiques et agronomiques des principaux terroirs viticoles de l’Anjou (France). Conséquences pour la viticulture

Abstract

Une étude conduite dans le cœur du vignoble A.O.C. angevin, sur une surface d’environ 30.000 ha, a permis de caractériser et cartographier finement (levé au 1/12.500), sur le plan des facteurs naturels, les différentes unités de terroir présentes. Pour cela, on a mis en œuvre une méthode basée sur le concept d’Unité Terroir de Base (U.T.B.). Elle utilise, à une même échelle cartographique, une clef géologique (stratigraphie et lithologie) et une clef agro-pédologique (modèle de terrain : roche, altération, altérite) pour identifier et zoner l’U.T.B. Une caractérisation agronomique de chaque U.T.B. a été faite sur le plan physique et chimique en mettant en œuvre les outils et mesures de la science du sol et de l’agronomie. Au plan viticole, une caractérisation de l’U.T.B. a également été conduite, grâce à l’utilisation d’algorithmes experts élaborés spécialement pour avoir une estimation chiffrée des principales variables de fonctionnement du système terroir / vigne : réservoir utilisable en eau pour la vigne, potentiel de précocité du terroir, potentiel de vigueur et rendement. L’effet terroir sur la vigne et le vin a été abordé par l’intermédiaire d’une enquête menée, au niveau de la parcelle, auprès de chaque vigneron de la zone étudiée.
Les résultats concernant les plus importantes Unités Terroir de Base de l’Anjou sont présentés. Ils montrent des différences souvent considérables entre U.T.B., en ce qui concerne les propriétés agro-viticoles. En conséquence, l’adaptation des porte-greffes, des pratiques agro-viticoles, de même que l’aptitude de l’U.T.B. à produire divers types de vins et le choix des cépages qui en résulte, sont discutés.

A study realized in the vineyard of Anjou, allowed to characterize and to map the different viticultural “terroirs”. A method based on the concept of the “Base Terroir Unit” (B.T.U) was utilized. It uses a geologic key (stratigraphical and lithological components) and a ground model known as: Roche, Altération, Altérite, to identify and to cartography the B.T.U. B.T.U. corresponds to an entity (a territory) that is sufficiently homogeneous with respect to functioning of the “terroir” / vine / wine system and that has a surface area sufficient for enhanced value through viticulture. An agronomic study was made for every T.B.U. from the point of view of physical and chemical factors. Viticultural potentialities were studied by using algorithms experts which allowed to estimate : soil water capacity, potential for early growth and potential of vigour, for each B.T.U. The results obtained were confirmed by means of the viticultural survey, amongst the wine growers.
Results show important differences between Base “Terroir” Units. As a consequence, the adaptation of the vineyard and the viticultural practices are discussed

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

R. Morlat*, P. Guilbault**, D. Rioux**, S. Cesbron**

*U.R.V.V. INRA. 42, rue Georges Morel. 49071 Angers. France
**Equipe Terroirs d’Anjou. Angers

Tags

IVES Conference Series | Terroir 2000

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