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IVES 9 IVES Conference Series 9 Identification of natural terroir units for viticulture: Stellenbosch, South Africa

Identification of natural terroir units for viticulture: Stellenbosch, South Africa

Abstract

[English version below]

Une unité de terroir naturel (UTN) peut être définie comme une unité de terre qui est caractérisée par une relative homogénéité topographique, climatique, géologique et pédologique. De telles unités sont de grande valeur pour mieux comprendre le système terroir/vigne/vin. Le but de cette étude est de caractériser la région viticole du Bottelaryberg. – Simonsberg-Helderberg en utilisant une information digitale existante et d’identifier des UTN en utilisant un Système d’information Géographique.

Cette région d’étude est située au sud-ouest de Stellenbosch et couvre approximativement 25 000 ha. Elle est située près de l’Océan Atlantique, bordée par des montagnes et découpée par une vallée produisant une variation spatiale notable de tous les paramètres climatiques. La géologie est complexe en raison de nombreux mouvements tectoniques et mélange de la roche-mère. Malgré un fort degré de variation du sol qui est difficile à représenter dans les associations pédologiques, un schéma de la distribution des sols a pu être noté en relation avec la position du paysage.

Les unités morphologiques de terrain, l’altitude et l’exposition ont été utilisées comme premières clés pour l’identification des UTN. De larges catégories de sols et attributs géologiques pour les sols résiduels ont été inclus à un niveau secondaire aboutissant à 203 unités. Ces unités doivent aussi être caractérisées en fonction de l’étendue à laquelle la proximité de la mer a une influence sur les caractères climatiques ainsi que du potentiel vitivinicole qui leur est associées.

A natural terroir unit (NTU) can be defined as a unit of land that is characterised by relatively homogenous topography, climate, geological substrate and soil. Such units are invaluable for better understanding of the terroir/vine/wine system. The aim of this study was to characterise the Bottelaryberg-Simonsberg-Helderberg wine growing area using existing digital information and to identify NTU using a Geographic Information System.

The study area was situated to the south west of Stellenbosch and covered an area of approximately 25 000 ha. It is bordered by mountains, situated close to the Atlantic Ocean and bisected by a river valley resulting in notable spatial variation of all climatic parameters. The geology is complex due to the high degree of tectonic movement and mixing of parent material. Despite a high degree of soil variation that is difficult to represent in soil associations, a pattern of soil distribution could be noticed in relation to landscape position.

Terrain morphological units, altitude and aspect were used as primary keys for the identification of NTU. Broad soil categories and geological attributes for residual soils were included at a secondary level resulting in 203 units. These units must be characterised with respect to the extent to which proximity to the sea has an influence on climatic characteristics as well as the associated viticultural and oenological potential.

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DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

V.A. CAREY (1,2); E. ARCHER (2) and D. SAAYMAN (3)

(1) ARC lnfruitec-Nietvoorbij, Private Bag X5026, 7599 Stellenbosch, South Africa
(2) Department of Viticulture and Oenology, Stellenbosch University, Private· Bag Xl, 7 602 Mati el and, South Africa
(3) Distell, P.O. Box 184, 7599 Stellenbosch, South Africa

Keywords

Unité de terroir naturel, Système d’information Géographique, topographie, géologie, sol
Natural terroir units, Geographic Information System, topography, geology, soil

Tags

IVES Conference Series | Terroir 2002

Citation

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