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IVES 9 IVES Conference Series 9 Paysages viticoles et terroir dans l’OAC Ribeira Sacra (Galice, NO de l’Espagne)

Paysages viticoles et terroir dans l’OAC Ribeira Sacra (Galice, NO de l’Espagne)

Abstract

[English version below]

La notion d’Appellation d’Origine Contrôlée (AOC), repose sur l’existence d’un lien entre les caractéristiques du terroir et la qualité et la typicité de la production (DELAS, 2000). Si pendant longtemps, ce lien n’est apparu que comme le fruit de l’empirisme, les recherches entreprises dernièrement ont permis de fonder scientifiquement les relations complexes entre fonctionnement des milieux naturels et aptitude à une production de qualité.
L’aire d’AOC Ribeira Sacra s’étend sur presque 195 km au large des versants escarpés du Miño et du Sil, dans la Galice (Espagne). Cette AOC couvre presque 1100 hectares, soit 5,2% de la surface viticole galicien, produisant en moyenne 22000 hl du vin. Enfoncées de plusieurs centaines de mètres dans les vieilles surfaces d’aplanissement du massif ancien, les vallées du Miño et du Sil et les parties inférieures de certains de leurs affluents (Bibei, Cabe, Bubal et Mao), ont été découpées en un extraordinaire escalier de terrasses viticoles. Réservées à la viticulture –la vigne est souvent l’unique culture et lorsqu’elle n’existe pas, le versant est abandonné aux broussailles-, la construction de ces terrassettes (appelées “socalcos” par les paysans) a exigé un travail gigantesque de remodelage des versants et leur entretien demandait des soins constants.
Dans ces vallées en gorge, les terrasses viticoles occupent souvent tout le versant et encerclent les rares chicots rocheux qui n’ont pu être conquis. Ces terrasses, le plus souvent entaillées dans des roches granitiques, sont en effet de remarquables constructions: chaque “socalco”, qui suit les courbes de niveau sur des pentes qui atteignent parfois 45 degrés, est soutenu par un mur de pierre sèche et sa largeur est souvent si faible qu’il ne peut accueillir qu’une seule rangée de ceps (les gradins n’ont souvent plus d’un mètre de large). Ces terrasses constituent un exemple remarquable de formations anthropiques très effectives du point de vue de minimiser l’érosion du sol et de la formation de microclimats particulièrement adaptés aux besoins de la vigne.
Par leurs caractéristiques constructives on peut parler de véritables anthrosols. Du point de vue pédologique la région est bien homogène, même s’il y a quelques variations en raison des conditions particulières d’orographie, de la nature de la roche-mère (granites, gneiss, ardoises). Par contre, l’influence de l’altitude (200 à 450 m) et l’exposition (de l’ouest a sud-est) est évidente.
L’étude vise à caractériser les conditions climatiques, géologiques et pédologiques des différentes situations des vignobles d’OAC Ribeira Sacra, pour faire une première approximation à l’influence de l’altitude et l’exposition au zonage vitivinicole de l’AOC Ribeira Sacra.

The concept of Appellation d’Origine (AOC) is based on the existence of a link between the characteristics of the soil and quality and specificity of production grape and quality wine. This AOC include 1100 hectares (5.2% of the Galicia vineyard), planted on the valleys of the rivers Miño and Sil. The vine is planted in terraces, with different altitude (200-450 m) and exposition (west to southeast), example of anthropogenic formations very effective in terms of minimizing soil erosion and formation of microclimates particularly suited to the needs of vine. The area is divided into five sub-zones, with different edaphoclimate characteristics, Chantada, Amandi, Ribeiras do Miño, Ribeiras do Sil-Ourense, Quiroga-Bibei. The diversity of local climates allows to produce different type of cultivars, white (Albariño and Godello), as red (including Mencía, Brancellao and Merenzao).
This study aims to characterize the climatic conditions, geological and soil of vineyards of different situations from OAC Ribeira Sacra, to know the influence of altitude and exposure on wine characteristics.

DOI:

Publication date: December 3, 2021

Issue: Terroir 2010

Type: Article

Authors

Queijeiro J. (1), Vilanova M. (2), Rodriguez I. (1), de la Montaña J. (1)

(1) Sciences Faculty of Ourense, Edificio Politécnico, As Lagos s/n 32004. Ourense, Spain
(2) Misión Biológica de Galicia, Spain

Contact the author

Keywords

Ribeira Sacra, sols, pente, altitude, exposition
Mesoclimate, slope, bench terraces, altitude, exposition

Tags

IVES Conference Series | Terroir 2010

Citation

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