Terroir 1996 banner
IVES 9 IVES Conference Series 9 Analyse et modélisation des transferts thermiques dans un sol de vignoble. Effets des techniques culturales

Analyse et modélisation des transferts thermiques dans un sol de vignoble. Effets des techniques culturales

Abstract

Les facteurs naturels tels que le milieu dans lequel est cultivée la vigne jouent un rôle important sur la qualité du vin. Si on veut élaborer un bon vin, il est en effet essentiel de produire un raisin de qualité. Pour cela, il faut valoriser et optimiser l’effet terroir qui, pour l’instant, joue un rôle qui n’est pas très bien connu. Il est donc indispensable, par exemple, de disposer de relations scientifiquement établies et bien quantifiables pour faire admettre le système des aires d’origines contrôlées. R. Morlat (1989) et G. Seguin (1970) ont déjà réalisé des études sur le rôle de certains facteurs du sol sur la qualité du raisin. Ils ont notamment montré l’importance de la température du sol et du contenu en eau. Les relations entre la qualité et le terroir doivent cependant encore être clarifiées et surtout quantifiées afin d’être intégrées dans un système d’aide à la décision permettant d’optimiser les systèmes de conduite en fonction des facteurs naturels du site étudié.

Nous avons choisi, dans un premier temps, de nous intéresser principalement aux températures du sol. Ce facteur est en effet très important car il conditioime la croissance de la plante et certaines propriétés physiques du sol. La plupart de ces processus ne réagissent pas linéairement avec la température, il est donc indispensable de disposer de nombreuses données pour pouvoir évaluer les effets journaliers des températures du sol sur ces mécanismes. La mesure de la température du sol pose de gros problèmes car elle nécessite un dispositif qui est très lourd au niveau de l’installation, surtout dans les sols de vignoble, généralement hétérogènes. De plus, la mise en place des capteurs perturbe le milieu introduisant ainsi un biais dans les grandeurs qui seront mesurées.

C’est pour ces raisons que nous avons choisi de développer un modèle de transfert thermique applicable aux sols de vignobles. L’utilisation de lois physiques décrivant les échanges et des méthodes d’analyse et de modélisation micrométéorologiques paraissent aptes à apporter des réponses au problème posé par la recherche des facteurs jouant un rôle dans la qualité du raisin. Il en est de même pour l’explication des effets de différentes méthodes culturales (désherbage, travail du sol, enherbement).

Il est bien évident qu’il existe d’autres facteurs influant sur la qualité du raisin qui peuvent aussi caractériser l’effet “terroir”. Par exemple, la nutrition azotée et minérale de la plante joue aussi un rôle important, il est donc nécessaire d’étudier la disponibilité de ces éléments dans le sol, ainsi que leurs modes de transfert. De même, le climat de la région concemée est capital, il influe sur la plupart des grandeurs qui sont étudiées. Ces facteurs sont donc, dans un premier temps, étudiés séparément, l’objectif étant à terme la construction d’un modèle complet de l’élaboration de la qualité du raisin, où sont inclus tous les paramètres du climat, du terroir et du système de conduite.

Les transferts thermiques et hydriques sont étroitement liés, ils interagissent, on peut donc difficilement envisager des émdes séparées de ces deux phénomènes. On peut cependant considérer, du moins dans un premier temps, l’état hydrique comme une variable d’entrée.

Le but de l’étude entreprise est donc de comprendre et de quantifier les effets de différents types ouétats de sols et de différents mode de culture sur l’évolution de la température en profondeur. Pour cela, une bonne connaissance physique des transferts thermiques est nécessaire pour arriver à relier les caractéristiques thermodynamiques du sol à la propagation et au stockage de la chaleur.

DOI:

Publication date: March 25, 2022

Type: Poster

Issue: Terroir 1996

Authors

E. PRADEL, P. PIERI

Laboratoires de Bioclimatologie et d’Agronomie – Domaine de la Grande Ferrade – 33883 Villenave D’Ornon

Tags

IVES Conference Series | Terroir 1996

Citation

Related articles…

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.

Current climate change in the Oplenac wine-growing district (Serbia)

Serbian autochthonous vine varieties Smederevka (for white wines) and Prokupac (for rosé and red wines) are the primary representatives of typical characteristics of wines and terroir of numerous wine-growing areas in Serbia. In the past, these varieties were the leading vine varieties, however, as the result of globalization of winemaking and the trend of consumption of wines from widely prevalent vine varieties, they were replaced by introduced international varieties. Smederevka and Prokupac vine varieties are characterized by later time of grape ripening, and relative sensitivity to low temperatures. Climate conditions can be a restrictive factor for production of high-quality grapes and wine and for the spatial spreading of these varieties in hilly continental wine-growing areas.
This paper focuses on the spatial analysis of changes of main climate parameters, in particular, analysis of viticultural bioclimatic indices that were determined for the purposes of viticulture zoning of wine-growing areas in the period 1961-2010, and those same parameters determined for the current, that is, referential climate period (1988-2017). Results of the research, that is, analysis of climate changes indicate that the majority of examined climate parameters in the Oplenac wine-growing district improved from the perspective of Smederevka and Prokupac vine varieties. These studies of climate conditions indicate that changes of analyzed climate parameters, that is, bioclimatic indices will be favorable for cultivation of varieties with later grape ripening times and those more sensitive to low temperatures, such as the autochthonous vine varieties Smederevka and Prokupac, therefore, it is recommended to producers to more actively plant vineyards with these varieties in the territory of the Oplenac wine-growing district.

Legacy of land-cover changes on soil erosion and microbiology in Burgundian vineyards

Soils in vineyards are recognized as complex agrosystems whose characteristics reflect complex interactions between natural factors (lithology, climate, slope, biodiversity) and human activities. To date, most of the unknown lies in an incomplete understanding of soil ecosystems, and specifically in the microbial biodiversity even though soil microbiota is involved in many key functions, such as nutrient cycling and carbon sequestration. Soil biological properties are indicative of soil quality. Therefore, understanding how soil communities are related to soil ecosystem functioning is becoming an essential issue for soil strategy conservation. Here, we propose to assess the importance of land-cover history on the present-day microbiological and physico-chemical properties. The studied area was selected in the Burgundian vineyards (Pernand-Vergelesses, Burgundy, France) where land occupation has been reconstructed over the last 40 years. Soil samples were collected in five areas reflecting various land cover history (forest, vineyards, shifting from forest to vineyards). For each area, physico-chemical parameters (pH, C, N, P, grain size) were measured and DNA was extracted to characterize the abundance and diversity of microbial communities. The obtained results show significant differences in the five areas suggesting that present-day microbial molecular biomass and bacterial taxonomic is partly inherited from past land occupation. Over longer period of time, such study of land-uses legacies may help to better assess ecosystem recovery and the impact of management practices for a better soil quality and vineyards sustainability.

Effect of the commercial inoculum of arbuscular mycorrhiza in the establishment of a commercial vineyard of the cultivar “Manto negro

The favorable effect of symbiosis with arbuscular mycorrhizal fungi (AMF) has been known and studied since the 60s. Nowadays, many companies took the chance to start promoting and selling commercial inoculants of AMF, in order to be used as biofertilizers and encourage sustainable biological agriculture. However, the positive effect of these commercial biofertilizers on plant growth is not always demonstrated, especially under field conditions. In this study, we used a commercial inoculum on newly planted grapevines of a local cultivar grafted on a common rootstock R110. We followed the physiological status of vines, growth and productivity and functional biodiversity of soil bacteria during the first and second years of 20 inoculated with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseaeAMF at field planting time and 20 non-inoculated control plants. All the parameters measured showed a neutral to negative effect on plant growth and production. The inoculated plants always presented lower values of photosynthesis, growth and grape production, although in some cases the differences did not reach statistical significance. On the contrary, the inoculation supposed an increase of the bacterial functional diversity, although the differences were not statistically significant either. Several studies show that the effect of inoculation with AMF is context-dependent. The non-favorable effects are probably due to inoculation ineffectiveness under complex field conditions and/or that, under certain conditions, AMF presence may be a parasitic association. This puts into question the effectiveness of its application in the field. Therefore, it is recommended to only resort to this type of biofertilizer when the cultivation conditions require it (e.g., very low previous microbial diversity, foreseeable stress due to drought, salinity, or lack of nutrients) and not as a general fertilization practice.

Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

[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"...