Terroir 1996 banner
IVES 9 IVES Conference Series 9 Methodology and zoning of A.O.C. natural soils. Example of “Pic Saint-Loup”

Methodology and zoning of A.O.C. natural soils. Example of “Pic Saint-Loup”

Abstract

[English version below]

Les travaux menés, dans le cadre du programme départemental pour la connaissance et la valorisation des terroirs viticoles, sur l’aire A.O.C. Coteaux du Languedoc / Pic Saint-Loup ont permis d’appliquer à l’échelle d’une Appellation d’Origine Contrôlée (13 communes), une méthodologie d’étude axée sur les aspects sol/climat/topographie qui concourent à l’identification des terroirs naturels, facteurs de typicité des vins. Dans un premier temps, un «diagnostic» de l’ensemble des critères du milieu naturel a été réalisé. Après avoir défini le cadre géologique, une prospection agro-pédologique au 1/10.000ème a permis de cartographier les différentes unités de sol ainsi que leurs positions topographiques. Les conditions climatiques sont également précisées d’un point de vue statistique (stations météo au sein de l’aire et stations limitrophes).

Dans un second temps, il était intéressant d’associer plus étroitement ces caractéristiques agro­environnementales à la culture de la vigne et à l’élaboration d’un vin typique. On approche ainsi au plus près de la notion de «terroir». Dans ce cadre, une singularité bioclimatique du Pic Saint-Loup a été identifiée sur la base de 3 indices viticoles corrélés à des caractéristiques intrinsèques et spécifiques des vins du Pic Saint-Loup. Les différentes unités de terroir naturel ont été cartographiées (typologie du sol, avec une estimation de la disponibilité en eau, associée au bilan radiatif) et décrites sous les différents aspects qui font leurs identités.

The works led, within the local program for the knowledge and the valorization of the wine soils, on the area A.O.C. Coteaux du Languedoc / Pic Saint-Loup allowed to apply on the scale of a registrated appellation origin (13 municipalities), a methodology of study centered on aspects ground/climate/topography which contribute to the identification of natural soils, factors of typical wines. At first, a «diagnosis » of ail the criteria of the natural environment was realized. Having definite the geologic frame, an agro-pedological prospecting to the 1/10.000th allowed mapping the various unities of ground as well as their topographic positions. The climatic conditions are also clarified by a statistical point of view (meteorological stations within the area and bordering stations).

In a second time, it was interesting to associate more strictly these agro-environmental characteristics to the culture of the vineyard and to the elaboration of a typical wine. One approaches so in closer the notion of “soil”. In this frame, a bioclimatic peculiarity of the Pic Saint Loup was identified on the basis of 3 wine indicators correlated in intrinsic and specific characteristics of wines of Pic Saint Loup. The various units of natural soil were mapped (typology of ground, with an estimation of the availability in water, associated to the radiative assessment) and described under the various aspects which make their identities.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Jean-Paul STORAÏ (1), Jean-Luc TONDUT (2)

(1) Conseil général de l’Hérault – 1000 rue d’Alco – F. 34087 Montpellier cedex 4
(2) Association Climatologique de l’Hérault – 85 avenue d’Assas – F 34000 Montpellier

Keywords

méthodologie, terroir naturel, sol, climat, viticulture
methodology, natural soil, ground, climate, vine growing(2) Association Climatologique de l’Hérault – 85 avenue d’Assas – F 34000 Montpellier

Tags

IVES Conference Series | Terroir 2002

Citation

Related articles…

Evolution of the amino acids content through grape ripening: Effect of foliar application of methyl jasmonate with or without urea

The parameters that determine the grape quality, and therefore the optimal harvest time, suffer variations during berry ripening, related to climate change, with the widely known problem of the gap between technological and phenolic maturities. However, there are few studies about its incidence on grape nitrogen composition. For this reason, the use of an elicitor, methyl jasmonate (MeJ), alone or with urea, is proposed as a tool to reduce climatic decoupling, allowing to establish the harvest time in order to achieve the optimum grape quality. The aim was to study the effect of MeJ and MeJ+Urea foliar applications on the evolution of Tempranillo amino acids content throughout the grape maturation. Three treatments were foliarly applied, at veraison and 7 days later: control (water), MeJ (10 mM) and MeJ+Urea (10 mM+6 kg N/ha). Grape samples were taken at five stages of maturation: day before the first and second applications, 15 days after the second application (pre-harvest), harvest day, and 15 days after harvest (post-harvest). The amino acids analysis of the samples was carried out by HPLC. Results showed that the evolution of amino acids was similar regardless of the treatment; however, foliar applications influenced the nitrogen compounds content, i.e., there was no qualitative effect but quantitative one. Most of the amino acids reached their maximum concentration in pre-harvest, being higher in grapes from the treatments than in the control. In general, no differences in grape amino acids content were observed between MeJ and MeJ+Urea treatments. Foliar applications with MeJ and MeJ+Urea enhanced the grape amino acids content, without affecting their profile, helping to optimize their quality and allowing to establish a more complete grape ripening standard. Therefore, MeJ and MeJ+Urea foliar applications can be a simple agronomic practice, which has shown promising results in order to enhance the grape quality.

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

A multidisciplinary approach to evaluate the effects of the training system on the performance of “Aglianico del Vulture” vineyards

Vineyards are complex agro-ecosystems with high spatial and temporal variability. An efficient training system may counteract the adverse effects of this variability. Moreover, considering the climate change issues, choosing an efficient training system that enhances water use and protects the vines from radiative thermal stress has become a priority for the farmers. A multidisciplinary approach that assesses the soil-crop-yield-wine relationships of vineyards in a distributed and holistic way could bring added knowledge on the behavior of the different training systems. This ongoing research aimed to implement a multidisciplinary approach to study the behavior of “Aglianico del Vulture” grapevines trained with two different systems: a spurred cordon (SC) and an “Alberello in parete” (AL), grown in a high-quality wine production area of Basilicata region (Italy). The approach merged several methods and scales of soil, ecophysiology, must/wine quality, and spectral data collection to assess the influence of the training system. Homogeneous zones (HZs) in both training systems were defined through a procedure based on geomorphological classification, unmanned aerial vehicles (UAV) images analysis, and a traditional soil survey supported by geophysical scanning. During the 2021 season, TDR probes monitored soil water content, while grapevine health status was assessed using eco-physiological measurements (LWP, chlorophyll content, PSII photosynthetic efficiency, LAI, and point-based field spectroscopy). These grapevine in-vivo measurements validated the spectral vegetation indexes (NDVI, RENDVI, CVI, and TVI) derived from the UAV multispectral imagery, which monitored the grapevine status in a distributed and non-invasive way. Grape yield, quality of berries, must and wine were measured to assess the effects of the training systems. The first experimental year results showed the variability of the vineyards and revealed relationships among soil parameters, crop characteristics, and vegetation indices of the SC and AL training systems. This multidisciplinary study could bring new insights into the vineyard training system’s effects on grape yield and wine quality.

Comparison of imputation methods in long and varied phenological series. Application to the Conegliano dataset, including observations from 1964 over 400 grape varieties

A large varietal collection including over 1700 varieties was maintained in Conegliano, ITA, since the 1950s. Phenological data on a subset of 400 grape varieties including wine grapes, table grapes, and raisins were acquired at bud break, flowering, veraison, and ripening since 1964. Despite the efforts in maintaining and acquiring data over such an extensive collection, the data set has varying degrees of missing cases depending on the variety and the year. This is ubiquitous in phenology datasets with significant size and length. In this work, we evaluated four state-of-the-art methods to estimate missing values in this phenological series: k-Nearest Neighbour (kNN), Multivariate Imputation by Chained Equations (mice), MissForest, and Bidirectional Recurrent Imputation for Time Series (BRITS). For each phenological stage, we evaluated the performance of the methods in two ways. 1) On the full dataset, we randomly hold-out 10% of the true values for use as a test set and repeated the process 1000 times (Monte Carlo cross-validation). 2) On a reduced and almost complete subset of varieties, we varied the percentage of missing values from 10% to 70% by random deletion. In all cases, we evaluated the performance on the original values using normalized root mean squared error. For the full dataset we also obtained performance statistics by variety and by year. MissForest provided average errors of 17% (3 days) at budbreak, 14% (4 days) at flowering, 14.5% (7 days) at veraison, and 17% (3 days) at maturity. We completed the imputations of the Conegliano dataset, one of the world’s most extensive and varied phenological time series and a steppingstone for future climate change studies in grapes. The dataset is now ready for further analysis, and a rigorous evaluation of imputation errors is included.

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.