Mapping and tracking canopy size with VitiCanopy

In viticulture, the challenges of local climate modelling are multiple: taking into account the local environment, fine temporal and spatial scales, reliable time series of climate data, ease of implementation and reproducibility of the method. At the local scale, recent studies have demonstrated the contribution of spatialization methods for ground-based climate observation data considering topographic factors such as altitude, slope, aspect, and geographic coordinates (Le Roux et al, 2017; De Rességuier et al, 2020). However, these studies have shown questions in terms of the reproducibility and sustainability of this type of climate study. In this context, we evaluated the potential of MODIS thermal satellite images validated with ground-based climate data (Morin et al, 2020). Previous studies have been encouraging, but questions remain to be explored at the regional scale, particularly in the dynamics of the massive use of bioclimatic indices to classify the climate of wine regions. The results at the local scale were encouraging, but this approach was tested in the current study at the regional scale. Several objectives were set: 1) to evaluate the downscaling method for land surface temperature time series, 2) to identify regional thermal structure variations. We used weekly minimum and maximum surface temperature time series acquired by MODIS satellites at a spatial resolution of 1000 m and downscaled at 500 m using topographical variables. Two types of analyses were performed:

The use of soil conservation practices in wine grape production is becoming common throughout the world in response to an increased awareness of the value of soil health to maintain crop productivity and environmental quality. However, little information is available on the meaning of soil health within a viticultural context, and what soil properties should be targeted to achieve both the agronomic and environmental goals of wine grape producers. Conservation practices lead to increases in soil organic matter which may improve soil water retention, and increase soil C content therefore constituting a potential avenue to adapt to droughts and sequester C. Well-known management practices such as the use of cover crops, compost or no-till, although effective, seem to result in highly variable outcomes in soil organic matter and other soil health indicators. This variability is likely associated to the application of the practices in different soils and climates. Thus, integration of soil health building practices needs a thorough understanding of their efficacy under different conditions. Furthermore, additions of soil organic matter could trigger emissions of CO2 and N2O, a potent greenhouse gas that could represent a potential tradeoff of soil conservation practices. Finally, nutrient and water availability may be affected by the increase in soil organic matter having consequences for vine balance and grape quality.

L’aire des A.O.C. Madiran et Pacherenc du Vic-Bilh est située sur le piémont nord-occidental des Pyrénées, au nord du cône de Ger.

The postharvest dehydration of grapes is a traditional practice to obtain wines with unique traits (e.g. sweet, dry/reinforced). The modern facilities (dehydrating rooms) used for this purpose are equipped with systems for artificially controlling the inside environment parameters, to obtain the desired dehydration kinetic and preserve the grapes from grey mold (Botrytis cinerea) infection, However, the conditioning systems are extremely energy-demanding and the identification and practical applications of solutions effective in controlling/reducing the postharvest decay would reduce the costs of the operation of the dehydration facilities. To this end, we explored the potential of ozone-based treatments on harvested grapes and preliminarily tested if the treatment could impact the normal behavior and metabolism of grapes during the traditionally slow dehydration practice.

The grape volatile compounds determine the wine quality and typicity [1]. Thus, looking for agronomic tools to improve its composition it is of great interest in the sector [2]