Elaboration des cartes conseils pour une gestion du terroir à l’échelle parcellaire: utilisation d’algorithmes bases sur des paramètres physiques du milieu naturel

The “Anjou Terroirs” programme aims at bringing the necessary scientific basis for a ratio­nal and reasoned exploitation of the technical itinerary of the terroir. The scale study is 1/12500. For the mapping, many parameters, such as the granulometry or the depth of soil are observed to each point of caracterisation. However, the composition and the quality of grapes do not depend directly on these parameters, but is influenced by variables such as water supply or vine precocity. These variables cannot be easily mapped, but can be esti­mated by algorithms based on expertise. The precision and the content of the cartographie study allow to quantify these main variables wich influence the vine behavior. It is therefore possible to build advisory maps that can be used by the vine growers at the scale of the par­cellary. As an example, a map on rootstock adaptation to the terroir has been published. Thanks to the knowledge obtained through a network of experimental plots, five fundamen­tal factors seems determinant to us, to choose a rootstock in Anjou condition: water sup­ply, natural drainage, iron chlorosis power of soil, vigour potential and precocity potential conferred by the terroir.