Study of wine-terroirs in Switzerland

A multidisciplinary approach aiming at studying the grape-growing areas also referred as «Terroir» was initiated a few years ago in Switzerland. Collaborative studies are carried out on soil characteristics (I. Letessier, bureau Sigales; S.Burgos, Ecole d'ingénieurs deChangins), climatic parameters (Swiss Federal Institute of Technology, Lausanne) and aspects of the plant physiology (Agroscope Changins-Wädenswil ACW). The study of the soil includes the collection of geological and pedological characteristics and viticulturists' practical knowledge. A large diversity in type and composition of soils was found and highlighted the importance of the parameter of soil water holding capacity (SWHC). In order to evaluate climatic components of the «Terroir», a model was built resulting in a climatic index including temperature, radiation and wind protection. Agronomical studies revealed a good correlation between plant physiology (water status, vegetative growth, sugar accumulation in berries) and water content present in the soil (SWHC). Current studies aim at determining the influence of pedoclimatic factors on the quality of the final product in wine-growing areas in Switzerland.