The growth of grapevine depends on soil and climate conditions. Different grapevine varieties have various demands for heat and water. As a result, different winegrowing regions have been formed, combining areas with the same or very similar climatic conditions. Numerous bioclimatic indices have been made to show the plant-atmosphere relationship, which determine the suitability of an individual producing region for grapevine varieties according to various weather variables (air and soil temperature, precipitation, sun radiation, air humidity). This thesis presents most frequently used bioclimatic indices in viticulture (Winkler index, Huglin index, dryness index, cold night index and bioclimatic index) and their applicability. The Winkler index calculates the sum of effective temperatures during the grapevine growing season. In addition to the amount of effective temperatures, Huglin index also takes into account maximum temperatures during the grapevine growing season. The cold nights index is based on the average night temperature during the ripening of grape berries affecting the wine aromas and colour. Dryness index gives the amount of water available in the soil for the plant, and the bioclimatic index takes into account the effective temperatures, solar radiation and precipitation. According to the values of the indices, winegrowing areas are divided into several climate classes, and for the Winkler and Huglin, an grapevine assortment is also proposed on the basis of these classes. Bioclimatic indices help us in the regionalization of winegrowing areas, and according to the forecasted climate changes, we can also use them to predict changes in the grape growing the future.
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