Terroir 1996 banner
IVES 9 IVES Conference Series 9 Impact of urbanization on optimum wine Terroirs in the Bordeaux region sample of one township of the Entre-Deux-Mers Area

Impact of urbanization on optimum wine Terroirs in the Bordeaux region sample of one township of the Entre-Deux-Mers Area

Abstract

[English version below]

L’étude présentée porte sur une commune de l’Entre-Deux-Mers dans le bordelais. Nous caractérisons dans un premier temps les potentialités des sols vis-à-vis de la production de vins rouges de qualité (délimitation de terroirs grâce à la prise en compte des couvertures pédologiques et des caractéristiques morphométriques du terrain : pentes, expositions, convexités. Dans un second temps, nous récapitulons l’évolution historique des occupations des sols depuis 1790 : l’emplacement des vignes est ainsi localisé sur les terroirs respectifs des communes. Enfin, une étude prospective résultant d’enquêtes sur l’utilisation du foncier, situe le devenir prévisible de l’espace étudié (en particulier dans ses composantes viticoles et urbaines).
Les résultats mettent en évidence l’influence de la pression d’urbanisation sur la consommation du patrimoine rare et non renouvelable que sont les terroirs viticoles. Les enjeux patrimoniaux collectifs (protection d’un terroir) se manifestent ici en opposition avec des enjeux patrimoniaux individuels : les prix du foncier à bâtir orientent les stratégies des propriétaires fonciers sur de tels terroirs. De plus, l’urbanisation contribue à la disparition d’unités de production lorsqu’elles se trouvent enclavées dans des parcellaires devenus urbains. Les méthodes utilisées dans le cadre de cette étude peuvent constituer la base d’outils d’aménagement pour permettre la préservation d’un patrimoine d’une grande importance économique comme paysagère, que sont les terroirs viticoles. Le patrimoine sol est une composante essentielle à prendre en compte dans un objectif de développement durable : il y a une dimension économique de la filière viti-vinicole, dimension sociale (emplois directs et dérivés : tourisme, culture), dimension environnementale (imperméabilisation des surfaces urbaines, destruction de sols, métamorphose des paysages).

This study was carried out on a township of the Entre-Deux-Mers area in the Bordeaux wine region. We initially focused on soil potentialities as regards high quality red wine production. Criteria such as soil type, slope, aspect (sunlight) and curvatures were taken into account to produce a map of best potential “terroirs”. Secondly, land cover changes were studied from 1790 to the present. Past and present vineyard delimitations were compared with the above mentioned map. At the same time, interviews carried out on wine producers allowed us to foresee changes in land use. The main goal was to assess the evolution of urbanization on optimum wine “terroirs”. Results show that there are losses of those “terroirs” due to urbanization. In this case, collective and individual interests are opposed because in Entre-Deux-Mers, the price of arable land is lower than that of land zoned for building. Some wine producers prefer to sell their land for building purposes. As a result, some vineyards are surrounded by urban areas and are likely to disappear in a short period of time (access for machines is more difficult and pesticide treatments are not easily accepted).  It is important to protect wine growing soils because they constitute a valuable and a nonrenewable resource. They are the basis of the Bordeaux region’s landscapes and many economic (i.e. tourism) and social activities depend directly on their protection.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

P. CHERY (1), X. CHONE (2), A. ARMITAGE-LEE, L. COMMAGNAC (1), M-F. SlAK. (1)

(1) LARGE, ENITA de Bordeaux, BP 201, f-33175 GRADIGNAN cedex
(2) Laboratoire d’Ecophysiologie de la Vigne, ENITA de Bordeaux, BP 201, f33175 GRADIGNAN cedex

Keywords

Terroir viticole, AOC, urbanisation, Entre-Deux-Mers, analyse spatiale
Terroir, urbanization, Bordeaux wine region, spatial analysis

Tags

IVES Conference Series | Terroir 2002

Citation

Related articles…

Grape must quality and mesoclimatic variability in Fruška Gora wine-growing region, Serbia

The Fruška Gora mountain is a traditional wine-growing region in Serbia situated in the Pannonian Basin. Due to such a position, the vicinity of the Danube River and the presence of concave configuration, it is suitable for grape production. This paper provides analyses of spatial variations in meteorological parameters and grape juice quality within Fruška Gora wine region over three consecutive vintages (2018-2020). The examined period can be defined as warm with cool nights during September (AVG 18,9°C; GDD 1918°C; CI 12°CF) and with the presence of mesoclimatic variability. The East part of the study area was somewhat drier and hotter compared to other parts of the region. The analyses of grape must samples (190 in total) of five cultivars (Cabernet-Sauvignon, Merlot, Chardonnay, Sauvignon blanc and Grašac (Welschriesling)) commonly grown across the region (19 sites), were performed using Fourier Transform Infrared Technology (FTIR). Among all cultivars, Sauvignon blanc was harvested first in the East area (DOY=246±5, GDD at harvest=1552±74, 22.2±0.7 °Brix), while the latest harvest was recorded for Cabernet-Sauvignon in the West (DOY=283±5, GDD at harvest=1936±187, 23.4±1.0 °Brix ). Both the red and white cultivars had higher acidity and YAN in the grape must if the vines were grown in the North and East compared to South and West areas. According to PCA analysis, Grašac showed the lowest variation in grape must chemical composition. Thus, the results confirm that Grašac is the most stable cultivar in Fruška Gora. All monitored cultivars reached technological fruit ripeness by the end of the growing season. However, it was difficult to reach full ripeness of red cultivars, mostly beacuse of uncoupling of technolocical and phenolic ripeness. Thus, Cabernet-Sauvignon had higher variations in GDD sums at harvest compared to other cultivars, which probably increased variations in grape must quality.

Grapevine yield-gap: identification of environmental limitations by soil and climate zoning in Languedoc-Roussillon region (south of France)

Grapevine yield has been historically overlooked, assuming a strong trade-off between grape yield and wine quality. At present, menaced by climate change, many vineyards in Southern France are far from the quality label threshold, becoming grapevine yield-gaps a major subject of concern. Although yield-gaps are well studied in arable crops, we know very little about grapevine yield-gaps. In the present study, we analysed the environmental component of grapevine yield-gaps linked to climate and soil resources in the Languedoc Roussillon. We used SAFRAN data and IGP Pays d’Oc wine yields from 2010 to 2018. We selected climate and soil indicators proving to have a significant effect on average wine yield-gaps at the municipality scale. The most significant factors of grapevine yield were the Soil Available Water Capacity; followed by the Huglin Index and the Climatic Dryness Index. The Days of Frost; the Soil pH; and the Very Hot Days were also significant. Then, we clustered geographical zones presenting similar indicators, facilitating the identification of resources yield-gaps. We discussed the number of zones with the experts of IGP Pays d’Oc label, obtaining 7 zones with similar limitations for grapevine yield. Finally, we analysed the main resources causing yield-gaps and the grapevine varieties planted on each zone. Mapping grapevine resource yield-gaps are the first stage for understanding grapevine yield-gaps at the regional scale.

Different soil types and relief influence the quality of Merlot grapes in a relatively small area in the Vipava Valley (Slovenia) in relation to the vine water status

Besides location and microclimatic conditions, soil plays an important role in the quality of grapes and wine. Soil properties influence…

austrianvineyards.com: online viewer of all designations of Austrian wine

To digitally record and present all the origins of Austrian wines in the same perfect and clear way was the motivation for the Austrian Wine Marketing Board (Austrian Wine) to start with the project in 2018. In June 2021 the results were presented to the public in an online viewer showing all the designations of Austrian wine, available at https://austrianvineyards.com in a largely barrier-free manner. The online viewer provides tailored individual maps fitted to the respective zoom level. The smallest unit of wine-origins in Austria is called Ried and is displayed in a plot-specific manner highlighting areas under vine. Information on the Ried include administrative district, winegrowing municipality, cadastral municipality, large collective vineyard site, specific winegrowing region, generic winegrowing region, winegrowing area and, in many cases, an illustrative picture. Complementary data on the size, elevation (minimum-maximum), orientation (in 8 sectors plus flat) and gradient (minimum, maximum, average) are based on the area under vine according to the EU’s Integrated Administration and Control System. Additional information covers climate data. The diagrams are taken from the monthly breakdown of data in the annals of the Central Institute for Meteorology and Geodynamics, Austria provide a display of values for air temperature, precipitation, and sunshine hours for the reference year and the long-term average. Seasonal aggregated data on temperature, precipitation, and sunshine hours complete the display. Short descriptions with emphasis on geology and soil, field name in historical maps, etymology of the denomination, and main planted variety complements the available information for the main designations in the online viewer. These descriptions are compiled by winegrowers, geologists, historians, and journalists. All the information and data can be extracted to a pdf-file. Printed vineyard maps are also available. Missing content regarding wine origins in Styria will be completed in winter 2021/22.

Spatial variability of temperature is linked to grape composition variability in the Saint-Emilion winegrowing area

Elevated temperature during the grape maturation period is a major threat for grape quality and thus wine quality. Therefore, characterizing the grape composition response to temperature at a larger scale would represent a crucial step towards adaptation to climate change. In response to changes in temperature, various physiological mechanisms regulate grape composition. Primary and secondary metabolisms are both involved in this response, with well-known effects, for example on anthocyanins, and lesser known effects, for example on aromas or aroma precursors. At the field scale or at the regional scale, however, numerous environmental or plant-specific factors intervene to make the effects of temperature difficult to distinguish from overall variability. In this study, it was attempted to overcome this difficulty by selecting well-characterized situations with differing temperatures.
A long-term study of air temperature variability across several Merlot vineyards in the Saint-Emilion and Pomerol wine producing area found significant temperature differences and gradients at various time scales linked to environmental factors. From this study area, a few sites were selected with similar age, soil and training system conditions, and with repeated and contrasted temperature differences during the maturation period. The average temperature difference during the maturation period was about 2°C between cooler and warmer sites, a difference similar to that expected under future climate change scenarios. In close vicinity to the temperature sensors at each site, grape berries were sampled at different times until full maturity during 2019 and 2020. Also, berries from bunches on either side of the row were analyzed separately, allowing an investigation of bunch exposure effect associated with the coupling of berry temperature and solar radiation. Four replicates of pooled berries for each time – site – bunch exposure combination were obtained and analyzed for biochemical composition. Analyses of variance of the biochemical composition data collected at different sampling times reveal significant effects associated with temperature, site, and bunch azimuth. For instance, anthocyanins in grape skins are clearly influenced by temperature and solar radiation exposure, with up to 30% reduction in warmer conditions.