Soil-plant water status and wine quality: an physically based approach to terroir analysis

The ZOViSA Project (Viticultural zoning at farm scale) tests a new physically oriented approach to terroir analysis, strongly rooted on hydropedology and aiming to achieve a better use of environmental features with respect to plant requirement and wine production. The physics of our approach is defined by the use of soil-plant-atmosphere simulation models which apply physically-based equations to describe the soil hydrological processes and solve soil-plant water status. The project is conducted in two farms of southern Italy (Del Monte-Ponte(BN) and Quintodecimo-Mirabella Eclano (AV)) located in the Campania region and devoted to quality wines production (Aglianico and Falanghina DOC). In one site (Quintodecimo farm) the soil spatial distribution was recognized; then the soil-plant water status was monitored in two experimental plots from two different soils. Daily soil water variables (through TDR probes and tensiometers), crop development (biometric and physiological parameters) and daily climate variables (temperature, solar radiation, rainfall, wind) were monitored. The SWAP model was calibrated and applied in the two experimental plots to estimate soil-plant water status in different crop phenological stages. The effects of crop water status on crop response and wine quality was evaluated in two different pedo-systems, comparing the crop water stress index with both: crop physiological measurement (leaf gas exchange, chlorophyll-a fluorescence, leaf water potential, chlorophyll content, LAI measurement), grape bounches measurement (berry weight, sugar content, titrable acidity, etc.) and wine quality (aromatic response). Finally a preliminary "spatial application" of the model was carried out and different terroirs defined.