Terroir 1996 banner
IVES 9 IVES Conference Series 9 Methodology for soil study and zoning

Methodology for soil study and zoning

Abstract

La caractérisation des sols en vue d’une étude de terroirs viticoles peut être réalisée à différents niveaux de complexité, suivant le nombre de variables pris en compte et suivant le fait que celles-ci sont spatialisées ou non. La cartographie des sols est une approche très complète, notamment lorsqu’elle s’appuie sur des cartes géologiques et géomorphologiques réalisées au préalable. Néanmoins, même si elle est très détaillée, la caractérisation des sols reste par définition descriptive. Pour expliquer le lien entre le terroir, la qualité des vins et leur typicité, il faut prendre en compte les interactions qui existent entre la vigne et son environnement (sol et climat): c’est le domaine de l’écophysiologie. Les études écophysiologiques sont pluridisciplinaires et ont le défaut d’être lourdes à mettre en œuvre. Plusieurs équipes ont proposé des méthodologies pour alléger les études de sol. Lorsqu’on doit réaliser une étude sur une grande surface, on peut réaliser au préalable une cartographie à grande échelle sur un secteur de référence pour établir des lois de distribution des sols. Etant donné l’importance de la profondeur du sol sur le fonctionnement de la vigne, un modèle roche-altération-altérite a été proposé. La télédétection peut alléger le travail à réaliser sur le terrain et permettre de cartographier des pédo-paysages. Des indicateurs physiologiques peuvent renseigner sur l’état nutritionnel de la vigne (eau et éléments minéraux), en relation avec l’offre du sol. Ces indicateurs permettent de générer différentes couches d’information sur le fonctionnement de la vigne, qui peuvent être complétées par de l’information concernant le sol et la qualité des raisins et valorisées à travers le concept de la viticulture de précision. Ceci aboutira à terme à de véritables études écophysiologiques spatialisées.

Soil is an important factor of “terroir”. Soil studies can be more or less complex depending on the number of variables taken into account and depending on whether they are spatialized or not. Soil mapping, carried out after preliminary geological and geomorphological studies, is an interesting approach. Nevertheless, the interactions between the soil, the climate and the vine have to be taken into account by means of an ecophysiological approach to explain how “terroir” acts on vine behaviour, wine quality and wine style. Because “terroir” studies are very time consuming and therefore expensive, several lightened methodologies have been developed. When the soils of a large area have to be mapped at a small scale, a small representative reference sector can be mapped previously at a large scale. The reference sector will provide soil distribution laws that can be applied to the large area. To simplify the soil mapping, soils can be grouped depending on their depth, which is a determining factor in water and nutrient supply to the vines. Remote sensing can help to reduce soil sampling density. Physiological indicators can be used to assess vine water and nitrogen supply, in relation to the soil type. Several layers of information about the soil, the vine development and berry constitution can be related in a Geographical Information System (G.I.S.). Precision viticulture is the application of this technique to asses variability inside a plot of vines. Although it is still a relatively new approach, it is a powerful tool that can provide a spatialized ecophysiological approach of “terroir”.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

C. VAN LEEUWEN (1, 2), Ph. CHERY(1), J.-Ph. ROBY (1), D. PERNET (1), J.-P. GOUTOULY (3) and J.-P. GAUDILLERE (3)

(1) ENITA de Bordeaux, 1 Crs du Général de Gaulle, BP 201, 33175 Gradignan-Cedex, France
(2) Faculté d’Œnologie, 351 Crs de la Libération, 33405 Talence-Cedex, France
(3) INRA-Agronomie, BP 81, 33883 Villenave d’Omon, France

Contact the author

Keywords

terroir, sol, zonage, cartographie, vigne, régime hydrique, télédétection, viticulture de précision, indicateurs physiologiques, secteur de référence, Système d’information Géographique (S.I.G.)

terroir, soil, zoning, mapping, vine, water status, remote sensing, precision viticulture, physiological indicators, reference sector, Geographical Information System (G.I.S.)

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.

Climate change impacts on Douro Region viticulture and adaptation measures

Climate has a significant impact in the success of any agricultural system, with a direct influence on the crops suitability to a given region, interfering on yield and quality and also with the economic sustainability of the productive activity. In the Douro Demarcated Region (RDD), as in most regions of the Mediterranean climate, the scarce precipitation (33% has less than 600 mm per year), and your high variability, associated with high rates of evapotranspiration during the summer, is usually one of the fundamental factors that limit the grapevine development, as well as the production and quality of the harvest. Thus, facing the scenario in temperature changes for the next decades (1.5-2.5°C) and confirming the predictions of precipitation decreases and/or great variability in the occurrence of heat waves and intense rainfall, the consequences for slope stability in mountain viticulture and sustainability of all operations involved, are risks to be taken into account. In this way, a deepest and sustained knowledge regarding the adaptation measures to adverse environmental conditions is of a crucial importance, enabling a more efficient adaptation of plant growth conditions and the optimization of production and quality of the grapevines. The development of this work, carried out in two commercial vineyards, one located in Soutelo do Douro, São João da Pesqueira, Cima Corgo sub-region, and another located in Numão, Vila Nova de Foz Côa, Douro Superior sub-region, it seeks to establish a relationship between climatic elements and physiological, productive and qualitative parameters, as well as to evaluate the effectiveness of adaptation measures, including different types of deficit irrigation (2002-2019) and the application of shading nets (2019-2020) in the physiological, viticultural and oenological behavior in the Touriga Nacional and Moscatel Galego Branco varieties, respectively. The results showed that the application of deficit irrigation allowed to significantly reduce the impact of the adverse weather conditions at key moments in the development of the grapevine, particularly in the period immediately before veráison and maturation, reducing the negative effects on the physiological processes and productivity, without compromise the must quality parameters. On the other hand, the application of shading nets significantly reduced de leaves temperature, allowing to increase the water potential, stomatal conductance and photosynthetic rate of grapes, which was reflected in the yield increase in the 2nd year of the study. For the maturation indicators, higher levels of total acidity, malic acid and assimilable nitrogen were obtained. The last measure presents a huge potential, being essential to carry out more years of trials to obtain stronger conclusions in terms of production parameters, but also in characteristics as important as the grape ripening components and the organoleptic characteristics of wines.

Effect of one-year cover crop and arbuscular mycorrhiza inocululation in the microbial soil community of a vineyard

The microbial composition of the soil is an important factor to consider in viticulture, since its influence on the “terroir” and on the organoleptic properties of the wine have been demonstrated. Different agronomic techniques have the potential to modify the composition and functionality of the soil microbial community. Maintaining green covers is known to increase soil microbial diversity. The direct application of inoculum of beneficial microorganisms to the soil has also been used to increase their abundance. However, the environmental conditions of each site seem to have a determining weight in the result of these practices. In this study, we compared the effect on the microbial community of a cover crop with legumes in autumn and the inoculation of grapevines with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseae in the previous spring. The study has been carried out in a vineyard in Binissalem, Mallorca, Spain. After applying the treatments, we will analyze the soil microbial communities using the data obtained from Illumina amplification of soil DNA from the 16S and ITS regions to analyze bacteria and fungi community, respectively. In addition, we will record the physicochemical characteristics of the soil at each sampling point. The result showed that agronomic management, in the short term, has less influence than soil characteristics on the composition of the soil microbiome. With these results, we can conclude that in a vineyard, agricultural techniques should focus on improving the characteristics of the soil to improve the biodiversity of the soil microbiota.

Modeling the suitability of Pinot Noir in Oregon’s Willamette Valley in a changing climate

Air temperature is the key driver of grapevine phenology and a significant environmental factor impacting yield and quality for a winegrape growing region. In this study the optimal downscaled CMIP5 ensemble for computing thegrowing season average temperature (GST) viticulture climate classification index was determined to spatially compute on a decadal basis predictions of the GST climate index and the grapevine sugar ripeness (GSR) model for Pinot Noir throughout the Willamette Valley (WV) American Viticultural Area (AVA). Forecasts for average temperature and a 220 g/L target sugar concentration level were computed using daily Localized Constructed Analogs (LOCA) downscaled CMIP5 historic and Representative Concentration Pathways (RCP) future climate projections of minimum and maximum daily temperature. We explore spatiotemporal trends of the GST climate classification index and Pinot Noir specific applications of the GSR phenology model for the WV AVA. Spatiotemporal computations of the GST climate index and Pinot Noir specific applications of the GSR model enable the opportunity to explore relationships between their computed values with one intent being to provide updated GST ranges that better align with current temperature-based modeling understanding of Pinot Noir grapevine phenology and the viticultural application of LOCA CMIP5 climate projections for the WV AVA. The Pinot Noir specific applications of the GSR model or the GST index with updated bounds indicate that the percent of the WV AVA area suitable for Pinot Noir production is currently at or near its peak value in the upper 80s to lower 90s of this century.