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IVES 9 IVES Conference Series 9 From local classification to regional zoning-the use of a geographic information system (GIS) in Franconia/Germany. Part 2: regional zoning of vineyards based on local climatic classifications

From local classification to regional zoning-the use of a geographic information system (GIS) in Franconia/Germany. Part 2: regional zoning of vineyards based on local climatic classifications

Abstract

En raison des vanations locales d’exposition et de déclivité, l’évaluation climatique des vignobles et des régions viticoles est très important pour la culture des raisins. De nombreuses informations différentes doivent être réunies et analysées afin de trouver la position optimale pour des cépages avec des périodes de maturité différentes qui ensuite déterminent la région. De nouveaux logiciels, tel qu’un Système d’information Géographique (SlG), permettent d’enregistrer et d’analyser en détail les facteurs importants.
L’un des objectifs d’une application du SIG en Franconie / Allemagne est une classification climatique des vignobles et l’introduction d’un zonage climatique. La somme de la radiation directe se situe au centre de l’évaluation climatique des surfaces viticoles, car elle détermine la quantité de chaleur reçue par une position. Ceci varie avec les conditions de relief, calculées à l’aide d’un modèle de terrain digital sur la base des cartes topographiques. Dans ces conditions, il est possible de cons tituer des cartes d’inclination et d’exposition. On peut en conclure que les zones de même déclivité et d’exposition reçoivent la même insolation.
Le calcul de la somme de radiation, particubèrement pendant les mois de maturité, permet un zonage climatique local et la délimitation des surfaces en Franconie aptes à la viticulture. Sur la base de la classification climatique, la quantité d’air froid, le risque de gel ainsi que la fréquence du brouillard peuvent être inclus dans l’évaluation. Partant de cette évaluation locale du climat, les régions de même clémence de climat peuvent être clairement délimitées.

The climatic valuation of vineyards and viticultural regions in the northern hemisphere bas a high importance for the cultivation of grape varieties with different ripeness development. A large amount of different information have to be compiled and analysed to work out the optimal locations for grape varieties with different ripeness periods within specific areas. New computer software such as a Geographic Information System (GIS) enables the detailed recording and analysis of viticulturally relevant factors.

One of the objectives of the GIS application in Franconia / Germany is the climatic classification of vineyards and the establishment of a climatic zoning. The main aspect of the climatic valuation is the sum of the direct radiation on vineyard sites. The local climate in northern viticultural regions is maµtly influenced by local variations of slope and exposition.
By means of digital terrain models based on topographie maps, slope and exposition are calculated with the GIS. A combination of these factors enables the creation of maps with many small-scaled areas, each showing specific slope and exposition. From this, numerous larger zones with equal slope and exposition are deduced which receive the same amount of energy.

The calculation of the amount of radiation, especially for the months of ripeness, enables a local climatic zoning and delimitation of areas in Franconia / Germany suitable for viticulture. Based on the climatic classification, the endangering of areas by cold air and frost and the frequency of fog can be also included into this valuation. Proceeding from the local. climatic classification, regions or zones of equal climatic conditions can be clearly determined.

DOI:

Publication date: February 15, 2022

Issue:Terroir 2002

Type: Article

Authors

S. MICHEL, A. SCHWAB and S. KÖNIGER

Bayerische Landesanstalt für Weinbau und Oartenbau, Abt. Weinbau und Rebenzüchtung, Hennstr. 8, D-97209 Veitshochheim, Germany

Contact the author

Keywords

zonage régional, SIG, classification climatique, topoclimat, gestion des surfaces viticoles
regional zoning, GIS, climatic classification, topoclimate, vineyard management

Tags

IVES Conference Series | Terroir 2002

Citation

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