La zonazione della D.O.C. Bolgheri (Castagneto C.): aspetti metodologici ed applicativi

The results of the first step of the zoning study carried out in Bolghery appellation area (Castagneto Carducci, Tuscany) in the 1993-1995 period have been recently published. Quality factors of Bolgheri appellation and different “terroirs ” were identified. The influence of site of cultivation (i.e. the ambience created and its immediate environment) on crop level, vine vegetative growth, grape composition and wine quality was the result of the combination of mesoclimatic conditions, soil characteristics, soil water and mineral nutrient availability. In this work the overall methodology and each phase of this zoning process are described and discussed. A particular emphasis is given to some parts of the zoning process:
(1) The detection of the existence of soil effects on grape yield and wine quality;
(2) The grapevine nutritional status and its relationships with nutrients availability in different soils;
(3) The use of descriptive analyses, combined with univariate and multivariate statistics, to define the sensory properties of wines obtained in the different presumed terroirs in Bolgheri appellation.
The second step, nowadays in progress, is the presentation of results to winegrowers and winemakers by the aid of maps and concise reports. At the same time results have to be verified and corroborated by further investigations. Even the limitations of the results of the zoning of Castagneto Carducci territory are presented: the large variability in observed vineyards and the lack of a balanced experimental design.