Terroir 1996 banner
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

Related articles…

Impact of climate variability and change on grape yield in Italy

Viticulture is entangled with weather and climate. Therefore, areas currently suitable for grape production can be challenged by climate change. Winegrowers in Italy already experiences the effect of climate change, especially in the form of warmer growing season, more frequent drought periods, and increased frequency of weather extremes.
The aim of this study is to investigate the impact of climate variability and change on grape yield in Italy to provide winegrowers the information needed to make their business more sustainable and resilient to climate change. We computed a specific range of bioclimatic indices, selected by the International Organisation of Vine and Wine (OIV), and correlated them to grape yield data. We have worked in collaboration with some wine consortiums in northern and central Italy, which provided grape yield data for our analysis.
Using climate variables from the E-OBS dataset we investigate how the bioclimatic indices changed in the past, and the impact of this change on grape productivity in the study areas. The climate impact on productivity is also investigated by using high-resolution convection-permitting models (CPMs – 2.2 horizontal resolution), with the purpose of estimating productivity in future emission scenarios. The CPMs are likely the best available option for this kind of impact studies since they allow a better representation of small-scale processes and features, explicitly resolve deep convection, and show an improved representation of extremes. In our study, we also compare CPMs with regional climate models (RCMs – 12 km horizontal resolution) to assess the added value of high-resolution models for impact studies. Further development of our study will lead to assessing the future suitability for vine cultivation and could lead to the construction of a statistical model for future projection of grape yield.

How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

One of the major issues for the wine sector is the impact of climate change linked to the increasing temperatures which affects physicochemical parameters of the grape varieties planted in Bordeaux vineyard and consequently, the quality of wine. In some varietals, the attenuation of their fresh fruity character is accompanied by the accentuation of dried-fruit notes [1]. As a new adaptive strategy on climate change, some winegrowers have initiated changes in the Bordeaux blend of vine varieties [2]. This study intends to explore the fruitiness in wines produced from grape varieties adapted to the future climate of Bordeaux. 10 commercial single–varietal wines from 2018 vintage made from the main grape varieties in the Bordeaux region (Cabernet franc, Cabernet-Sauvignon and Merlot) as well as from indigenous grape varieties from the Mediterranean basin, such as Cyprus (Yiannoudin), France (Syrah), Greece (Agiorgitiko and Xinomavro), Portugal (Touriga Nacional) and Spain (Garnacha and Tempranillo), were selected among 19 samples using sensory descriptive analyses. Both sensory and instrumental analyses were coupled, to investigate their fruity aroma expression. For sensory analysis, samples were prepared from wine, using a semi preparative HPLC method which preserves wine aroma and isolates fruity characteristics in 25 specific fractions [3,4]. Fractions of interest with intense fruity aromas were sensorially selected for each wine by a trained panel and mixed with ethanol and microfiltered water to obtain fruity aromatic reconstitutions (FAR) [5]. A free sorting task was applied to categorize FAR according to their similarities or dissimilarities, and different clusters were highlighted. Instrumental analysis of the different FAR and wines demonstrated variations in their molecular composition. Results obtained from sensory and gas chromatography analysis enrich the knowledge of the fruity expression of red wines from “new” grape varieties opening up new perspectives in wine technology, including blending, thus providing new tools for producers.

Elucidating vineyard site contributions to key sensory molecules: Identification of correlations between elemental composition and volatile aroma profile of site-specific Pinot noir wines

The reproducibility of elemental profile in wines produced across multiple vintages has been previously reported using grapes from a single scion clone of Vitis vinifera L. cv. Pinot noir. The grapevines were grown on fourteen different vineyard sites, from Oregon to southern California in the U.S.A., which span distances from approximately hundreds of meters to 1450 km, while elevations range from near sea level to nearly 500 m. In addition, sensorial (i.e. aroma, taste, and mouthfeel) and chemical (i.e. polyphenolic and volatile) differences across the different vineyard sites have also been observed among these wines at two aging time points. While strong evidence exists to support that grapes grown in different regions can produce wines with unique chemical and sensorial profiles, even when a single clone is used, the understanding of growing site characteristics that result in this reproducible differentiation continues to emerge. One hypothesis is that the elemental profile that a vineyard site imparts to the grape berries and the resulting wine is an important contributor to this differentiation in chemistry and sensory of wines. For example, various classes of enzymes that catalyze the formation of key aroma compounds or their precursors require specific metals. In this work, we begin to report correlations between elemental and volatile aroma profiles of site-specific Pinot noir wines, made under standardized winemaking conditions, that have been previously shown to be distinguished separately by these chemical analyses.

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.

Assessing the climate change vulnerability of European winegrowing regions by combining exposure, sensitivity and adaptive capacity indicators

Winegrowing regions recognized as protected designations of origin (PDOs) are closely tied to well defined geographic locations with a specific set of pedoclimatic attributes and strictly regulated by legal specifications. However, climate change is increasingly threatening these regions by changing local conditions and altering winegrowing processes. The vulnerability to these changes is largely heterogenous across different winegrowing regions because it is determined by individual characteristics of each region, including the capacity to adapt to new climatic conditions and the sensitivity to climate change, which depend not only on natural, but also socioeconomic and legal factors. Accurate vulnerability assessments therefore need to combine information about adaptive capacity and climate change sensitivity with projected exposure to new climatic conditions. However, most existing studies focus on specific impacts neglecting important interactions between the different factors that determine climate change vulnerability. Here, we present the first comprehensive vulnerability assessment of European wine PDOs that spatially combines multiple indicators of adaptive capacity and climate change sensitivity with high-resolution climate projections. We found that the climate change vulnerability of PDO areas largely depends on the complex interactions between physical and socioeconomic factors. Homogenous topographic conditions and a narrow varietal spectrum increase climate change vulnerability, while the skills and education of farmers, together with a good economic situation, decrease their vulnerability. Assessments of climate change consequences therefore need to consider multiple variables as well as their interrelations to provide a comprehensive understanding of the expected impacts of climate change on European PDOs. Our results provide the first vulnerability assessment for European winegrowing regions at high spatiotemporal resolution that includes multiple factors related to climate exposure, sensitivity, and adaptive capacity on the level of single winegrowing regions. They will therefore help to identify hot spots of climate change vulnerability among European PDOs and efficiently direct adaptation strategies.