ABSTRACT
The geology and geomorphology of the territory as well as microclimate are local geographical features that serve as natural ecological resources. These factors influence the biosynthetic activities of plants and their phenology, promoting biodiversity and the qualitative predispositions of grapes and wine. South Tyrol is one of the smallest wine-growing regions in Italy, but owing to its position amid the Alps, it is also one of the most multifaceted, a region of wide geographical diversity and remarkable ecological range, hosting a concentration of many different vine varieties and high quality wines. This applied territorial research investigates the particular environmental circumstances that favour this case. A data set describing approximately 26,000 vineyards and 5450 hectares has been employed to evaluate 18 subzones of wines and vines selected from 86 new geographical units defined within the DOC wine region. A new environmental mapping scheme called VHTG is proposed, based on the ecological indicators of grape variety, altitude, topoclimate and the geopedology of the vineyards. Using the VHTG method analyses, the comparisons between the territories of origin and their vine varieties can be rendered simpler and more direct, and it can distinguish the most suitable ecological conditions of wine production zones. It is now possible to examine more in detail the land suitability of the different cultivars, defined by the use of the ecological indicators summarized in the VHTG method. White grape varieties such as Sylvaner and Veltliner prefer high altitudes between 600 m and 900 m, a very high solar radiation SRI index from 80 to 95, and acidic sandy soils of silicate minerals. The most complete and intense tannic structure of regional Pinot Noir correlates to quite clayey soils with dolomite mineral, slightly alkaline, on vineyards at altitudes between 350 m and 410 m, with rather low SRI index from 60 to 75. Similar geopedological conditions favour Gewürztraminer, which, however, requests SRI from 75 to 85. Merlot and Cabernet vines are best expressed in the hottest regional sub-zones, on moderately clayey subalkaline soils at 250 - 350 m of altitudes and SRI around 80. The indigenous red grape variety Lagrein is mostly localized on alluvial cone at altitudes under 350 m, on soft and ventilated acid sands with volcanic silicate minerals.