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IVES 9 IVES Conference Series 9 From geomorphological analysis to terroirs geo-pedological zonation: the Madiran and Pacherenc of Vic-Bilh A.O.C. as case of study

From geomorphological analysis to terroirs geo-pedological zonation: the Madiran and Pacherenc of Vic-Bilh A.O.C. as case of study

Abstract

L’aire des A.O.C. Madiran et Pacherenc du Vic-Bilh est située sur le piémont nord-occidental des Pyrénées, au nord du cône de Ger. Sa délimitation parcellaire a été complétée par une étude géo-pédologique systématique. L’analyse du modelé des échines dissymétriques qui portent le vignoble montre que la nature et la distribution des formations superficielles sont contrôlées par les systèmes de pente et les roches mères. Une carte géomorphologique au 1/50000 a guidé l’implantation de 37 topolithoséquences analysées à l’aide de 227 profils ouverts. La synthèse des études de terrain et des analyses physico-chimiques (pH, texture, capacité d’échange, minéraux argileux … ) permet de définir 12 types de sols. Le regroupement de ces unités aboutit à deux cartes pédologiques d’échelles complémentaires au 1/25000 pour la zone test du bassin du Bergons et au 1/50000 pour l’aire des A.O.C. Le contexte géomorphologique, la nature des substrats et les propriétés physico-chimiques des sols définissent leurs potentialités agronomiques et une hiérarchisation en quatre classes d’aptitudes viticoles.

The A.O.C. Madiran and Pacherenc of Vic-Bilh area is located in the northwestern piedmont of the Pyrénées, in the north of the Ger cone. lts delimitation was complemented by a systematic geo-pedological study. The geomorphologic analysis of the vineyard dissymmetrical relieves shows that the type and the distribution of the surficial formations are controlled by the slope systems and the parent rocks. A physiographic map at 1/50000 scale guided to establish 37 topolithosequences studied with 227 soil profiles. The synthesis of the field works together with physico-chemical analysis (pH, texture, exchange capacity, clay minerais … ) permits to characterize 12 soils types. These units are consolidated in order to present two pedological maps at complementary scales: 1/25000 for the Bergons basin test zone and 1/50000 for the A.O.C. surface. The geomorphological context, the type of the substrates and the physico-chemical properties of these soils define their agronomic potentialities and a hierarchization in four wine-producing aptitude classes.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

D. CHAUVAUD

Université de Pau et des Pays de l’ Adour, Laboratoire de Géodynamique et Modélisation des Bassins Sédimentaires, CURS-IPRA – B.P. 1155 – 64013 Pau Cédex

Keywords

vignoble, analyse géomorphologique, carte géomorphologique, topolithoséquences, cartes pédologiques, aptitudes viticoles des sols
vineyard, geomorphological analysis, physiographic map, .topolithosequences, pedological maps, wine producing aptitudes of soils

Tags

IVES Conference Series | Terroir 2002

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