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IVES 9 IVES Conference Series 9 Preliminary studies of zoning applications in Goriška Brda (Collio) winegrowing region, Slovenia

Preliminary studies of zoning applications in Goriška Brda (Collio) winegrowing region, Slovenia

Abstract

[English version below]

Goriška Brda est la région viticole située le plus à l’ouest de la Slovénie, attenante au Collio d’Italie. Goriška Brda (2020 ha de vignobles) a une longue tradition d’élevage viticole. La proximité de la mer Adriatique (Golfe de Trieste) au sud-ouest et des Alpes Juliennes au nord contribue à un climat caractéristique et unique qui influe sur la croissance et la fertilité de la vigne. La constitution des sols, un climat typique et un relief mouvementé provoquent des différences dans la production du raisin, sa quantité et sa qualité. L’utilisation du zonage ou du microzonage permettraient d’atténuer les influences des facteurs climatiques et du sol sur la production de la vigne ou d’en profiter. Pour évaluer la signification des différents facteurs, nous avons résumé et réuni les modèles de différents auteurs. Nous avons déterminé la somme des températures effectives d’après WINKLER l’index héliothermique selon BRANAS et HUGLIN, le coefficient thermique d’après Kerner, le coefficient hydrothermique selon SELJANOV et l’index bioclimatique avec l’aide des données hydrométéorologiques de la moyenne de trente ans et de la moyenne de sept stations météorologiques pour 2000 et 2001. Pour une évaluation plus exacte des influences, nous avons utilisé des cartes pédologiques, de relief et des cartes digitales cadastrales. Avec les photographies aériennes digitales et le registre des producteurs de raisin et de vin, nous y avons déterminé la superficie totale des vignobles, la manière de production et la diffusion des différentes espèces. À cause de sa diffusion et de sa production exigeante, nous avons incorporé dans le modèle le cépage rouge cv. ‘Merlot’. À l’intérieur de la région, les différences de températures moyennes mensuelles, les précipitations moyennes et l’humidité moyenne de l’air dans la croissance de la vigne ont été démontrées à l’aide des mesures faites par les stations hydrométéorologiques. Les résultats des coefficients et des index ont montré des différences partiellement significatives statistiquement entre les stations (Statgraphics 4.0). Les différences statistiquement significatives sont apparues dans la quantité et la qualité du produit dans les vignobles en expérimentation.

Goriška brda is the most west winegrowing region in Slovenia; geographically it is the extension of the Italian winegrowing area known as Collio. The region comprehends 2020 ha of vineyards and is known as a traditional viticulture land since ever. The Adriatic Sea from Southwest and Julian Alps from North booth form the unique climate that has an important role upon the grapevine performance. The uneven soil types, the unique climate and the folded slopes cause the differential grapevine reaction giving a variety of quantity and quality of grapes. Defining the region into small regional units-‘microregionalisation’ could be the way to minimize the bad and turn to our account the good factors of the soil-climate combination. Different models were taken to evaluate the influential factors. We calculated the Winkler’s heat summation above 10°C threshold, heliotermical indexes (BRANAS, HUGLIN), termical coefficient (KERNER), hidrotermical coefficient (SELJANINOV) and bioclimatic index using the two years (2000 and 2001) meteorological data of seven weather stations in the region as well as the average data of the 30 years period (1961-1990). The digital pedological, geological, relief and cadastre maps were used to locate the vineyards and the examined factors. The complete vineyard sites were supervised with the data from vineyard practice to the varieties structure and their range. We included cv. ‘Merlot’ in our experiment, because of its growing expansion and climate demanding. Differences in average month temperature, average precipitation and average relative humidity are present within the winegrowing région. Results of calculate indexes and coefficients proved significant statistic differences in the data among different meteorological stations (Statgraphics 4.0). Also quantity and quality differences of yield among vineyards are statistic significant. Ail climatic and harvest differences within Goriska brda winegrowing region confirm a necessity by dividing this region into smaller winegrowing places (cca. 80 ha) and winegrowing positions (cca. 15 ha). Such ‘microregionalisation’ assures proper, cheaper wine growing and better quality of grape.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Denis RUSJAN (1), doc. dr. Zora KOROSEC-KORUZA (1), prof. dr. Lucka KAJFEZ-BOGATAJ (2)

(1) University of Ljubljana, Biotechnical Faculty, Agronomy Department, Viticulture Group, Jamnikarjeva 101, Ljubljana, Slovenija
(2) University of Ljubljana, Biotechnical Faculty, Agronomy Department, Jamnikarjeva 101, Ljubljana, Slovenija

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Keywords

viticulture, région viticole, zonage, index météorologique, merlot
viticulture, winegrowing region, zonage, meteorological index, merlot

Tags

IVES Conference Series | Terroir 2002

Citation

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