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IVES 9 IVES Conference Series 9 Climate and mesoclimate zonification in the Miño valley (Galicia, NW Spain)

Climate and mesoclimate zonification in the Miño valley (Galicia, NW Spain)

Abstract

[English version below]

Galicia est une région située dans le Nord-Ouest de l’Espagne avec une longe tradition de culture de la vigne. A jour d’oui la vigne occupe en Galicia presque 28.500 ha, desquelles 8.100 correspondent aux 5 zones ayant droit à l’appellation DO (« Denominación de Origen ») équivalent aux AOC françaises. Les vignobles sont souvent localisés dans la partie moyenne et méridionale de la Vallée du Miño, bien que s’élaborent aussi vins de qualité dans les rivages atlantiques du sud-ouest et au val du Támega dans l’extrême sud-est. Le climat général est du type maritime tempéré avec d’influences océaniques que petit a petit sont remplacées pour des influences méditerranéennes et continentales, vers le sud et l’est de la région.
Le but de ce travail est évaluer les limites des DO galiciennes, en tenant conte l’évolution des techniques et indices de zonage climatique.
En préliminaire, les conditions climatiques ont été précisées d’un point de vue statistique (stations météo au sein des aires viticoles et stations limitrophes). Puis, plusieurs indices bioclimatiques proposées par la littérature vitivinicole ont été calcules. Le calcul a été opéré aussi sur les données apportées au cours des dernières 5 années pour le nouveau réseau de stations automatiques du Gouvernement régional.
L’élaboration et l’interprétation des résultats de l’analyse statistique ont permit de définir quatre zones agroclimatiques bien différentes au point de vue climatique. Ces résultats démontrent aussi que dans la DO Rías Baixas, il y a au moins deux zones avec conditions climatiques assez différentes. En outre, les données apportées par les nouvelles stations automatiques, on permit d’identifier quelques zones climatiques similaires -à l’échelle de mesoclimat- à l’intérieur des DO traditionnelles.

Galicia is a region in Northwest Spain and has a long viticulture heritage. Today about 28,500 hectares are dedicated to vine growing and, of these, 8.100 has are protected under 5 distinct denominations of origin. Most of these zones are situated in the southern and central part of the region in and around the river Miño valley. Some high quality wines are also produced on the southwest coast and in the river Támega valley. The climate of this area is mild, fresh maritime with strong influences from the Atlantic which gradually give way to Mediterranean and continental inland tendencies as one goes inland to the East.
The main aim of this article is to demonstrate the suitability of the classification of today’s Galician AOCs given the latest information on the field of Climatic Zoning.
For this purpose, standardized climate data provided by the Spanish and the Galician meteorological services have been utilized as well as data provided over the last five years by a new network of automatic weather posts that complete the previous network.
These data were used to calculate as series of climatic indices according to various methodologies. This information was later processed statistically to identify the most relevant factors in the differentiation of the vine growing areas.
Results confirmed the existence of four very clearly defined different viticulture climates. It was also shown that within the vine-growing zone of the Rías Baixas at least two sectors exist with quite distinct climatic conditions. Furthermore, the statistic processing of the information provided by the new automatic weather stations advanced research in climatic zoning permitting the identification of a series of typical mesoclimates that appear within the interior of the traditional viticulture zones.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

D. Blanco, C., Alvarez, M.P., García, and J.M., Queijeiro

Vigo University, Plant Biology and Soil Science Department, Ourense Science Faculty, As Lagoas s/n 32004 Ourense, Spain

Contact the author

Keywords

Viticultural climatic characterization, viticultural zoning, mesoclimates, climatic indices

Tags

IVES Conference Series | Terroir 2004

Citation

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