Terroir 1996 banner
IVES 9 IVES Conference Series 9 First results obtained with a terrain model to characterize the viticultural «terroirs» in Anjou (France)

First results obtained with a terrain model to characterize the viticultural «terroirs» in Anjou (France)

Abstract

En Anjou, une méthode de caractérisation des terroirs viticoles a été développée. Elle utilise un modèle de terrain basé sur la profondeur de sol et son degré d’argilisation. Il génère trois types de milieu sol : roche, altération, altérite. Les hypothèses testées concernent l’effet des trois types de milieu sur l’àlimentation en eau, la précocité de cycle de la vigne, le potentiel de vigueur et de rendement ainsi que sur la composition des baies.
Pour cela, un réseau de parcelles expérimentales de Chenin et Cabernet franc, comportant 3 répétitions par unité de terroir, a été mis en place. Il permet d’étudier les deux principaux systèmes géologiques de l’Anjou (Briovérien et Ordovicien-Dévonien)
Les résultats de 2000 et 2001 (années pluvieuses) montrent pour le cépage Chenin que le débourrement est significativement plus précoce en milieu roche qu’en milieu altérite. Le milieu altération ne se différencie pas significativement des deux autres. En 2000, des différences significatives d’alimentation hydrique entre terroirs sont apparues à partir du mois de septembre pour le cépage Chenin, et à un degré moindre pour le Cabernet franc. Ainsi, le milieu roche entraîne un abaissement significatif du potentiel hydrique foliaire de base, malgré l’année pluvieuse. Le milieu altération ne se différencie pas du milieu roche. Sur spilite de l’Ordovicien-Dévonien, le milieu roche induit une contrainte hydrique plus forte que sur métagrauwacke du Briovérien. Les résultats d’analyses de δ13C des baies sont très significatifs et confrrment ceux du potentiel hydrique foliaire. Ces deux types de mesures montrent que la contrainte hydrique pour la vigne est significativement plus forte en milieu roche qu’en milieu altérite. Les baies du cépage Chenin, en milieux roche et altération, sont significativement plus riches en sucres qu’en milieu altérite. Les milieux roche sur schiste gréseux et métagrauwacke ont des teneurs inférieures à celles de la spilite. Avec le Cabernet franc, les baies semblent plus riches en sucres sur milieu roche que sur altérite. Le milieu roche induit des teneurs en anthocyanes et polyphénols significativement supérieures à celles de l’altérite; et cela aussi bien dans les baies que dans les vins. Ces premiers résultats, encore fragmentaires, semblent confirmer la plupart des hypothèses de travail avancées.

In Anjou vineyard, the viticultural “terroirs” are studied with a method based” on the concept of the “Basic Terroir Unit” (BTU). To identify and cartography the BTU, a terrain model based on the depth and the clay content of soil was elaborated. It generates three kinds of soil environments which are designated by the French terms of: “roche, alteration and altérite”. The hypothesis tested concern the effect of each type of environment on water supply regime, earliness and vigour of vine which are the main factors of the “terroir” effect, and also on berries composition.
A multisite network of 21 plots with Chenin and Cabernet franc varieties, was established in 2000. It samples the two main geologic systems of Anjou (Brioverian and Ordovician­ Devonian), with three replicates for each BTU.
The first results (2000 & 2001), show for the variety Chenin that bud break is earlier in the “roche” environment than in the “altérite” environment. The “alteration” is not different from were detected in September; for the Chenin variety and, at a less degree, for the Cabernet franc. So the “roche” environment involves a significant lowering of the predawn leaf water potential, despite a rainy season. There are no significant differences between the “alteration” and the “roche” environment. The “roche” environment on spilite from Ordovician-Devonian involves significantly more water constraint than on metagrauwacke from Brioverian. The results of δ13 C measurements in berries are highly significant and confirm the ones of the predawn leaf water potential. These two kinds of measures show that the water availability is greater in the “altérite” environment than in the “roche” environment. The must sugar content on “roche” and “alteration” environments was significantly higher than on “altérite”. The rock environment on sandstone schist and metagrauwacke have a lesser sugar content than on spilite. With the Cabernet franc variety, the “roche” environment involves significantly greater anthocyanins and polyphenolic amounts than the “altérite”; both in berries and in wines. These first results seem to confirm most of the hypotheses.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Fabrice BODIN and René MORLAT

Unité Vigne et Vin. Centre INRA d’Angers. 42 rue Georges Morel. BP57.
49071 Beaucpuzé Cedex. France

Contact the author

Keywords

modèle de terrain, précocité de cycle, alimentation hydrique, cépage, composition des baies
terrain model, precocity, water supply regime, grape variety, berry composition

Tags

IVES Conference Series | Terroir 2002

Citation

Related articles…

Under-vine management effects on grapevine production, soil properties and plant communities in South Australia

Under-vine (UV) management has traditionally consisted of synthetic herbicide use to limit competition between weeds and grapevines. With growing global interest towards non-synthetic chemical use, this study aimed to capture the effects of alternative UV management at two commercial Shiraz vineyards in South Australia, where the sole management variables were UV management since 2016. In adjacent treatment blocks, cultivation (CU) was compared to spontaneous vegetation (SV) in McLaren Vale (MV), and herbicide was compared to SV in Eden Valley (EV). Soil water infiltration rates were slower and grapevine stem water potential was lower in CU compared to SV in MV, with the latter having a plant community dominated by soursob (Oxalis pes-caprae) during winter; while in EV, there was little separation between the treatments. Yields were affected at both sites, with SV being higher in MV and HE being higher in EV. In MV, the only effect on grape must was a lower 13C:12C isotope ratio in CU, indicating greater grapevine water stress. In the grape must at EV, SV had higher total soluble solids, total phenolics, anthocyanins, and yeast available nitrogen; and lower pH and titratable acidity. Pruning weights were not affected by the treatments in MV, while they were higher in HE at EV. Assessments revealed that the differing soil types at the two sites were likely the main determinants of the opposing production outcomes associated with UV management. In the silty loam soil of MV, the higher yields in SV were likely due to more plant-available water, as a potential result of the continuous soil bio-pores formed by winter UV vegetation. Conversely, in the loamy sand soils of EV with a lower cation exchange capacity, the lower yields and pruning weights in SV suggest the UV vegetation competed significantly with the grapevines for available water and nutrients.

Impact of yeast derivatives to increase the phenolic maturity and aroma intensity of wine

Using viticultural and enological techniques to increase aromatics in white wine is a prized yet challenging technique for commercial wine producers. Equally difficult are challenges encountered in hastening phenolic maturity and thereby increasing color intensity in red wines. The ability to alter organoleptic and visual properties of wines plays a decisive role in vintages in which grapes are not able to reach full maturity, which is seen increasingly more often as a result of climate change. A new, yeast-based product on the viticultural market may give the opportunity to increase sensory properties of finished wines. Manufacturer packaging claims these yeast derivatives intensify wine aromas of white grape varieties, as well as improve phenolic ripeness of red varieties, but the effects of this application have been little researched until now. The current study applied the yeast derivative, according to the manufacture’s instructions, to the leaves of both neutral and aromatic white wine varieties, as well as on structured red wine varieties. Chemical parameters and volatile aromatics were analyzed in grape musts and finished wines, and all wines were subjected to sensory analysis by a tasting panel. Collective results of all analyses showed that the application of the yeast derivative in the vineyard showed no effect across all varieties examined, and did not intensify white wine aromatics, nor improve phenolic ripeness and color intensity in red wine.

Climate ethnography and wine environmental futures

Globalisation and climate change have radically transformed world wine production upsetting the established order of wine ecologies. Ecological risks and the future of traditional agricultural systems are widely debated in anthropology, but very little is understood of the particular challenges posed by climate change to viticulture which is seen by many as the canary in the coalmine of global agriculture. Moreover, wine as a globalised embedded commodity provides a particularly telling example for the study of climate change having already attracted early scientific attention. Studies of climate change in viticulture have focused primarily on the production of systematic models of adaptation and vulnerability, while the human and cultural factors, which are key to adaptation and sustainable futures, are largely missing. Climate experts have been unanimous in recognising the urgent need for a better understanding of the complex dynamics that shape how climate change is experienced and responded to by human systems. Yet this call has not yet been addressed. Climate ethnography, coined by the anthropologist Susan Crate (2011), aims to bridge this growing disjuncture between climate science and everyday life through the exploration of the social meaning of climate change. It seeks to investigate the confrontation of its social salience in different locations and under different environmental guises (Goodman 2018: 340). By understanding how wine producers make sense of the world (and the environment) and act in it, it proposes to focus on the co-production of interdisciplinary knowledge by identifying and foreshadowing problems (Goodman 2018: 342; Goodman & Marshall 2018). It seeks to offer an original, transformative and contrasted perspective to climate change scenarios by investigating human agency -individual or collective- in all its social, political and cultural diversity. An anthropological approach founded on detailed ethnographies of wine production is ideally placed to address economic, social and cultural disruptions caused by the emergence of these new environmental challenges. Indeed, the community of experts in environmental change have recently called for research that will encompass the human dimension and for more broad-based, integrated through interdisciplinarity, useful knowledge (Castree & al 2014). My paper seeks to engage with climate ethnography and discuss what it brings to the study of wine environmental futures while exploring the limitations of the anthropological environmental approach.

A blueprint for managing vine physiological balance at different spatial and temporal scales in Champagne

In Champagne, the vine adaptation to different climatic and technical changes during these last 20 years can be seen through physiological balance disruptions. These disruptions emphasize the general grapevine decline. Since the 2000s, among other nitrogen stress indicators, the must nitrogen has been decreasing. The combination of restricted mineral fertilizers and herbicide use, the growing variability of spring rainfall, the increasing thermal stress as well as the soil type heterogeneity are only a few underlying factors that trigger loss of physiological balance in the vineyards. It is important to weigh and quantify the impact of these factors on the vine. In order to do so, the Comité Champagne uses two key-tools: networking and modelization. The use of quantitative and harmonized ecophysiological indicators is necessary, especially in large spatial scales such as the Champagne appellation. A working group with different professional structures of Champagne has been launched by the Comité Champagne in order to create a common ecophysiology protocol and thus monitor the vine physiology, yearly, around 100 plots, with various cultural practices and types of soil. The use of crop modelling to follow the vine physiological balance within different pedoclimatic conditions enables to understand the present balance but also predict the possible disruptions to come in future climatic scenarios. The physiological references created each year through the working group, benefit the calibration of the STICS model used in Champagne. In return, the model delivers ecophysiology indicators, on a daily scale and can be used on very different types of soils. This study will present the bottom-up method used to give accurate information on the impacts of soil, climate and cultural practices on vine physiology.

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)