Terroir 2004 banner
IVES 9 IVES Conference Series 9 The use of remote sensing for intra-block vineyard management

The use of remote sensing for intra-block vineyard management

Abstract

[English version below]

L’unité de gestion technique d’un vignoble est aujourd’hui la parcelle. Néanmoins, au sein d’une même parcelle, la variabilité de l’expression végétative et de la constitution des raisins à maturité, peut être grande, en particulier à cause d’une hétérogénéité du sol. Dans une parcelle expérimentale, la surface foliaire a été deux fois plus élevée sur les placettes de forte vigueur par rapport à celles de faible vigueur. Le taux de sucres des baies a varié de 205 à 235 g/ L. Cette variabilité devrait être prise en compte dans une gestion optimale du vignoble. Des images ont été obtenues par la télédétection à haute résolution, dont les pixels représentent 100 à 200 cm2 de surface au sol. Des pixels contenant seulement de l’information du feuillage ont alors pu être isolés de l’image. A partir des données spectrales contenues dans ces photos, un indice de végétation appelé « NDVI » (Normalized Difference Vegetation Index) peut être construit pour caractériser la vigueur de la vigne. Des zones de vigueur variable ont été identifiées au sein d’une parcelle. La similitude entre les cartes du NDVI et des variables d’expression de la vigueur, démontre la faisabilité de cartographier la vigueur à l’aide du NDVI obtenu par télédétection haute résolution, et ainsi permettre d’expliquer les variations de certains paramètres qualitatifs de la vendange qui en découlent.

In vineyard management, the technical work unit is now the block. However, considerable variability can exist inside a block with regard to vegetative growth and fruit composition at ripeness, because of soil heterogeneity. In this research, vine characteristics were measured on 96 plots of a block of 0,3 ha. Leaf area was two times greater on the plots with the highest vigour compared to the leaf area on the plots with the lowest vigour. Berry sugar content varied from 205 to 235 g/L. Optimised vineyard management should take in account this variability. Variations in soil (depth, texture) can be surveyed by soil sampling and mapped. They can also be assessed more rapidly and more precisely by geophysics, a technique based on variations in soil resistance to electric current. Vine behaviour can be measured by means of physiological indicators: N-tester for vine nitrogen status, leaf water potential and carbon isotope discrimination (δ13C) for vine water status. To represent spatial variability of physiological parameters, repeated measurements are necessary on a great number of plots inside a block, making this approach very time and money consuming. Remote sensing can be considered as an interesting alternative way to map intra-block heterogeneity. In satellite pictures, one pixel represents more than one square meter on the soil. Because a vine row rarely exceeds 60 cm in width, these pixels contain both information from the vine canopy and from the soil, making them difficult to interpret. In high resolution remote sensing, pictures are taken at an altitude of approximately 300 meters. Pixels represent 100 to 200 square centimeters on the soil. Pixels containing only information from the canopy can thus be extracted from the picture. On these photographs, vine vigour can be characterised by transforming spectral data from the canopy into a vegetation index, for instance “NDVI” (Normalized Difference Vegetation Index). This approach was used in this study. Zones of variable vine vigour were identified inside a block. The high correlation between NDVI and vigour parameters demonstrates the possibility to map the vigour with the NDVI by means of high resolution remote sensing, and consequently to explain the variations of linked quality factors.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

E. Marguerit (1), J.-P. Goutouly (2), C. Azais (1), S. Merino (1), J.-P. Roby (1), C. Van Leeuwen (1)

(1) ENITA de Bordeaux-UMR Œnologie Ampélologie, 1 Crs du Général de Gaulle, BP 201, 33 175 Gradignan-cedex, France
(2) INRA-UMR Œnologie Ampélologie, ECAV, 71, av. Edouard-Bourlaux, BP 81, 33 883 Villenave d’Ornon Cedex

Contact the author

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

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.

Assessing the climate change vulnerability of European winegrowing regions by combining exposure, sensitivity and adaptive capacity indicators

Winegrowing regions recognized as protected designations of origin (PDOs) are closely tied to well defined geographic locations with a specific set of pedoclimatic attributes and strictly regulated by legal specifications. However, climate change is increasingly threatening these regions by changing local conditions and altering winegrowing processes. The vulnerability to these changes is largely heterogenous across different winegrowing regions because it is determined by individual characteristics of each region, including the capacity to adapt to new climatic conditions and the sensitivity to climate change, which depend not only on natural, but also socioeconomic and legal factors. Accurate vulnerability assessments therefore need to combine information about adaptive capacity and climate change sensitivity with projected exposure to new climatic conditions. However, most existing studies focus on specific impacts neglecting important interactions between the different factors that determine climate change vulnerability. Here, we present the first comprehensive vulnerability assessment of European wine PDOs that spatially combines multiple indicators of adaptive capacity and climate change sensitivity with high-resolution climate projections. We found that the climate change vulnerability of PDO areas largely depends on the complex interactions between physical and socioeconomic factors. Homogenous topographic conditions and a narrow varietal spectrum increase climate change vulnerability, while the skills and education of farmers, together with a good economic situation, decrease their vulnerability. Assessments of climate change consequences therefore need to consider multiple variables as well as their interrelations to provide a comprehensive understanding of the expected impacts of climate change on European PDOs. Our results provide the first vulnerability assessment for European winegrowing regions at high spatiotemporal resolution that includes multiple factors related to climate exposure, sensitivity, and adaptive capacity on the level of single winegrowing regions. They will therefore help to identify hot spots of climate change vulnerability among European PDOs and efficiently direct adaptation strategies.

Upscaling the integrated terroir zoning through digital soil mapping: a case study in the Designation of Origin Campo de Borja

homogeneous zones by intersecting several partial zonings of major factors that influence vineyard growth. Each of them follows specific process from their corresponding disciplines. Soil zoning specifically refers to a Soil Resource Inventory map that has traditionally been generated by conventional soil mapping methods. These methods have shortcomings in reaching fine cartographic and categorical details and involve significant expenses, which undermines their applicability. A new framework named Digital Soil Mapping has introduced quantitative models by statistical techniques to establish soil-landscape relationships and is able to provide intensive scale cartography.

In the present study, a microzoning at 1:10.000 scale is generated from an initial zoning, where the conventional soil map with polytaxic map units is replaced by a new one from digital techniques that disaggregates them. The comparison between the zonings considers a quantitative evaluation of capability for each Homogeneous Terroir Unit by means of the Viticultural Quality Index and its categorization based on its distribution by map. The spatial intersection of both maps gives rise to a confusion matrix in which the flows of class variations after the substitution are assessed.

The results show a five-fold increase in the number of Homogeneous Terroir Units identified and a larger differentiation among them, evidenced by a wider range in the capability index distribution. Both elements are accompanied by an increase in the detection of areas of higher potential within previously undervalued uniform zones.These features are a direct effect of the improvements brought by Digital Soil Mapping techniques and would verify the advantages of their implementation in the Integrated Terroir zoning. Eventually, such new highly detailed terroir units would benefit precision viticulture and sustainable management practices.

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.