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IVES 9 IVES Conference Series 9 The effect of soil and climate on the character of Sauvignon blanc wine

The effect of soil and climate on the character of Sauvignon blanc wine

Abstract

[English version below]

Un projet multidisciplinaire sur l’effet du sol et du climat sur la qualité du vin a débuté en Afrique du Sud il y a 5 ans. Des mesures sont effectuées sous culture sèche dans des vignes de Sauvignon Blanc dans six localités différentes, cinq dans le district de Stellenbosch et une à Durbanville. Au moins deux types de sol différents sont présents dans chaque localité. Les températures maximales moyennes en été varient de 28°C pour la localité la plus chaude à 25°C pour la plus froide. En général, les vins issus des localités les plus froides enregistrent des résultats les plus élevés pour l’intensité et la qualité des arômes. Quelques fois des vins issus de localités plus chaudes enregistrent cependant des résultats meilleurs que prévus. Ceci est attribué à des pratiques adéquates de préparation des sols qui résultent dans une bonne distribution des racines et une bonne gestion de la ramure.L’état hydrique des sols à la même localité montre des différences majeures malgré des sites d’expérimentation souvent éloignés de moins de 50 m l’un de l’autre. Ceci résulte dans de forts stress hydriques pour les vignes situées sur des sols qui ont une faible capacité hydrique. Les profils aromatiques des vins issus de différents sols à la même localité montrent aussi par conséquent des différences majeures. Les résultats mettent en évidence l’harmonie entre la nature de la texture/régime hydrique du sol et le climat de la saison. Une performance suSpérieure au cours d’une saison n’est pas nécessairement répétée la saison suivante.

Substantial climatic differences occur between localities in the districts of Stellenbosch and Durbanville.
In general, wines from coolest localities score the highest for intensity and quality of aroma.
In some cases wines from warmer localities score better than expected (adequate soil preparation, good canopy management).
Wine from soils at the same locality show major differences.
During dry summers wines from soils with higher water supplying capacities show highest aroma intensity, while the situation may be reversed during milder summers.
Harmony exists between the textural nature/water regime of a soil and climate experienced during a specific season.

DOI:

Publication date: March 2, 2022

Issue: Terroir 1998

Type: Article

Authors

KOBUS CONRADIE

ARC Fruit, Vine and Wine Research lnstitute, Nietvoorbij Centre for Vine and Wine. Private Bag X5026, 7599 Stellenbosch, South Africa

Tags

IVES Conference Series | Terroir 1998

Citation

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