Terroir 2006 banner
IVES 9 IVES Conference Series 9 Complementarity of measurements of electric resistivity of soils and ΔC13 of must in studies and valorization of wine terroirs

Complementarity of measurements of electric resistivity of soils and ΔC13 of must in studies and valorization of wine terroirs

Abstract

The correlations between vine water deficit cumulated over the ripening period of grapes, assessed by ΔC13 in must sugar, and the main analytic variables of grapes are significant. As a result ΔC13 is a useful tool in zoning homogeneous areas according to their technological qualities when harvesting. There is no significant correlation between ΔC13 in must sugar and soil electric resistivity in the same zone. Thus it is impossible to combine a few measurements of ΔC13 and a zoning of electric resistivity to distinguish areas of which the aptitudes are different. In the event of little water deficit (ΔC13<-25,5‰), a pedological study based on zoning by means of electric resistivity is a complementary tool of zoning according to water uptake conditions, since harvest quality varies a lot with the texture of the sub-soil and its geophysic behaviour.

DOI:

Publication date: December 22, 2021

Issue: Terroir 2006

Type: Article

Authors

Guillaume DESCHEPPER (1), Xavier CASSASSOLLES (2), Michel DABAS (2) and David PERNET(1)

(1) SOVIVINS, Centre Montesquieu, Allée Jean Rostand, 33650 Martillac, France
(2) GEOCARTA, 16 rue du Sentier, 75002 Paris, France

Contact the author

Keywords

geophysics, electric resistivity, ΔC13, water deficit, zoning, soil, terroir

Tags

IVES Conference Series | Terroir 2006

Citation

Related articles…

Conservation of intravarietal diversity in France: exhaustive overview and perspectives

Since the renewal of the French vineyard after the Phylloxera crisis, the panorama of cultivated varieties has dramatically changed. This current genetic erosion is due to the increasing interest

Projected changes in vine phenology of two varieties with different thermal requirements cultivated in La Mancha DO (Spain) under climate change scenarios

The aim of this work was to analyze the phenology variability of Tempranillo and Chardonnay cultivars, related to the climatic characteristics in La Mancha Designation of Origin, and their potential changes under climate change scenarios. Phenological dates referred to budbreak, flowering, veraison and harvest were analyzed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The thermal requirements to reach each of these phenological stages were calculated and expressed as the GDD accumulated from DOY=60. Changes in phenology were projected by 2050 and 2070 taking into account those values and the projected temperatures and precipitation, simulated under two Representative Concentration Pathway (RCP) scenarios –RCP4.5 and RCP8.5– using an ensemble of models. The average phenological dates during the period under study were, April 16th ± 6.6 days and April 5th ± 6.0 days for budbreak, May 31st ± 6.0 days and May 27th ± 5.3 days for flowering, July 26th ± 5.6 days and July 25th ± 5.8 days for veraison, and Ago 23rd ± 10.8 days and Ago 17th ± 9.0 days for harvest, respectively, for Tempranillo and Chardonnay. The projected changes in temperature imply an average change in the maximum growing season (April-August) temperatures of 1.2 and 1.9°C by 2050, and 1.6 and 2.6°C by 2070, under the RCP4.5 and RCP8.5 scenarios, respectively. A reduction in precipitation is predicted, which vary between 15% for 2050 under RCP4.5 scenario and up to 30% by 2070 under RCP8.5. The advance of the phenological dates for 2050, could be of 6, 7, 7, and 8 days for Tempranillo and 4, 6, 6 and 9 days for Chardonnay, respectively for budbreak, flowering, veraison and harvest under the RCP4.5 scenario. Under the RCP8.5 emission scenario, the advance could be up to 30% higher.

High and extreme high temperature effects on shiraz berry composition 

Climate change is leading to a rise in average temperature and in the frequency and severity of heatwaves, and is already significantly disturbing grapevine phenology and berry composition. With the evolution of the weather of Australian grape growing regions that are already warm and hot, flavonoids, for which biosynthesis depends on bunch microclimate, are expected to be impacted. These compounds include anthocyanins and tannins which contribute substantially to grape and wine quality. The goals of this project were to determine if berry tannin accumulation is sensitive to high temperature and to enhance knowledge on upper temperature limits for viable wine production, in turn informing critical timing for mitigation strategies.

Monferace a new “old style” for Grignolino wine, an autochthonous Italian variety: unity in diversity

Monferace project is born from an idea of 12 winegrowers willing to create a new “old style” Grignolino wine and inspired byancient winemaking techniques of this variety (1). Monferace wine is produced with 100% Grignolino grapes after 40 months of ageing, of which 24 in wooden barrels of different volumes. Grignolino is an autochthonous Italian variety cultivated in Piedmont (north-west Italy), recently indicated as a “nephew” of the famous Nebbiolo (2) and is used to produce three different DOC wines. The Monferace Grignolino is cultivated in the geographical area identified in the Aleramic Monferrato, defined by the Po and Tanaro rivers, in the heart of Piedmont and the produced wine is characterized by a high content of tannins, marked when young, that evolve over the years. Its color is generally slight ruby red and garnet red with orange highlights with ageing.

Viticultural practices: past, present and future

Practices in viticulture have greatly evolved in the last five decades. There were three objectives: improvement in the quality of the products, reduction in the production costs through mechanization