Terroir 2012 banner
IVES 9 IVES Conference Series 9 Geostatistical analysis of the vineyards in the canton of Geneva in relation to soil and climate

Geostatistical analysis of the vineyards in the canton of Geneva in relation to soil and climate

Abstract

Soil and climate maps at the 1:10000 scales exist for more than 12’000 ha of Swiss vineyards. The use of these maps as consulting tools for growers remains difficult due to the complexity of the relationship between terroir and the large number of grape varieties planted. The current distribution of varieties and rootstocks is the result of a long optimization process. This study aims at analyzing the relationships between grape varieties, soil characteristics and climatic conditions.
The study was performed on the 1365 ha of Geneva’s vineyards with 3885 digitalized parcels. The 19 grape varieties planted on at least 5 ha were matched with the soil and potential radiation maps. The surface of each variety-soil combination and the mean radiation were calculated for each parcel.

The analysis showed that grape varieties were primarily planted according to meso-climatic conditions. Late ripening varieties, like Syrah or Merlot, were always planted on parcels receiving higher amounts of radiation than those planted with Pinot noir or Gamaret. Minimum radiation was calculated for each variety. Traditional grape varieties (e.g. Gamay or Chasselas) were planted in all meso-climates, indicating that the warmest plots were not judged to be too warm for early varieties. Regarding soil characteristics, early varieties were more present on BRUNISOL, which mainly represented flatter areas of the vineyards (10 % mean slope) and late varieties on steeper areas (mainly CALCOSOL with 16 % mean slope).
The present study revealed actual practices and criterions used by growers to make planting decisions. It might indicate minimum climatic and soil requirements for a given variety in the canton of Geneva. Continued monitoring may show the adjustments made by the growers to correct unsuccessful planting decisions. The analysis of these adjustments provides useful information for vineyard consultants.

DOI:

Publication date: October 1, 2020

Issue: Terroir 2012

Type: Article

Authors

Stéphane BURGOS, Elisabeth FORTIER

École d’Ingénieurs de Changins, rte de Duiller 50, 1260 Nyon

Contact the author

Keywords

grape varieties, soil, climate, terroir, SIG, geostatistic, Geneva

Tags

IVES Conference Series | Terroir 2012

Citation

Related articles…

Revealing the Barossa zone sub-divisions through sensory and chemical analysis of Shiraz wine

The Barossa zone is arguably one of the most well-recognised wine producing regions in Australia and internationally; known mainly for the production of its distinct Shiraz wines. However, within the broad Barossa geographical delimitation, a variation in terroir can be perceived and is expressed as sensorial and chemical profile differences between wines. This study aimed to explore the sub-division classification across the Barossa region using chemical and sensory measurements. Shiraz grapes from 4 different vintages and different vineyards across the Barossa (2018, n = 69; 2019, n = 72; 2020, n = 79; 2021, n = 64) were harvested and made using a standardised small lot winemaking procedure. The analysis involved a sensory descriptive analysis with a highly trained panel and chemical measurement including basic chemistry (e.g. pH, TA, alcohol content, total SO2), phenolic composition, volatile compounds, metals, proline, and polysaccharides. The datasets were combined and analysed through an unsupervised, clustering analysis. Firstly, each vintage was considered separately to investigate any vintage to vintage variation. The datasets were then combined and analysed as a whole. The number of sub-divisions based on the measurements were identified and characterised with their sensory and chemical profile and some consistencies were seen between the vintages. Preliminary analysis of the sensory results showed that in most vintages, two major groups could be identified characterised with one group showing a fruit-forward profile and another displaying savoury and cooked vegetables characters. The exploration of distinct profiles arising from the Barossa wine producing region will provide producers with valuable information about the regional potential of their wine assisting with tools to increase their target market and reputation. This study will also provide a robust and comprehensive basis to determine the distinctive terroir characteristics which exist within the Barossa wine producing region.

Evolution of grapeseed composition during maturation and characterization of its impact on wine compound using molecular networks

Usually the winemaker consider the grapeberry maturity as an actor of the wine quality. Grape seed are frequently used as a marker to assess the grape maturity. The first aim of this study is to obtain a better understanding of the impact of grape seed maturity on the grape seed and grape berry composition.

Improving stilbenes in vitis Labrusca L. Grapes through methyl jasmonate applications

Grapes (Vitis sp.) are considered a major source of phenolic compounds such as flavonols, anthocyanins and stilbenes. Studies related to the beneficial effects of these compounds on health have encouraged research aimed at increasing their concentration in fruits. On this behalf, several plant growth regulators such as jasmonic acid and its volatile ester, methyl-jasmonate (MeJa), have demonstrated promising results in many fruits. However, Brazilian subtropical climate might interfere on treatment response. The present study aims to evaluate the application of MeJa in the pre-harvest period in Concord and Isabel Precoce grapes (Vitis labrusca L.).

Aroma typicity of Timorasso wines: influence of ageing on volatile organic compounds and sensory descriptors

‘Timorasso’ is an autochthonous white grape variety from southern Piedmont (Italy) used for producing wines in the Colli Tortonesi product designation of origin (PDO). Over the last decade, there has been a notable rise in its production, due to the increased interest of wine enthusiasts who prized its wine distinctive ageing notes [1].

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.