6533b7d4fe1ef96bd1261b4b

RESEARCH PRODUCT

Les terroirs viticoles : une méthodologie de zonage en fonction du sol

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description

Terroir is a key-concept in viticulture that is more and more widely recognized to explain variations in wine quality and wine style. Terroir refers to an area and thus possesses a geographical dimension. Hence, zoning of viticultural terroir is necessary. This paper addresses soil related aspects of terroir zoning. The first step of the zoning process is a clear identification of the objectives that are being pursued: demarcation of production areas, the adaptation of the viticultural management practices to variations in soil types or the protection of viticultural landscapes. The second step is the definition of a scale adapted to the objectives. The precision of the zoning increases with the scale, but so does its cost. Thirdly, a scientific discipline must be chosen for the zoning approach. Geology or geomorphology enable the production of synthetic maps at low costs for scales ranging from 1:50 000 to 1:250 000. However, several soil types can be located in the same geological or geomorphological unit and it is difficult to relate vine behaviour to geology or geomorphology. Soil mapping by a pedological approach at scales ranging from 1:2 000 to 1:50 000 allows to produce more refined maps that can be used for an agronomic interpretation. However, it is not possible to relate wine quality directly to soil type. Soil maps are more expensive than geological or geomorphological maps, because their implementation is more time consuming (auger drilling, soil pit studies). The use of new technologies, like Geographic Information Systems (GIS), Digital Elevation Models (DEM), Geophysics, remote sensing and geostatistics enable the production of more detailed maps at reduced costs. Viticultural zoning has to be validated by eco-physiological studies.