Influence of weather and climatic conditions on the viticultural production in Croatia

Abstract

The research includes an analysis of the impact of weather conditions on phenological development of the vine and grape quality, through monitoring of four experimental cultivars (Chardonnay, Graševina, Merlot and Plavac mali) over two production years. In each experimental vineyard, which were evenly distributed throughout the regions of Slavonia and The Croatian Danube, Croatian Uplands, Istria and Kvarner and Dalmatia, the dates of occurrence of the following phenophases are recorded: swelling and opening of buds, the beginning of flowering, the pattern and technological maturity of grapes (harvesting), representing BBCH phases 09, 68, 83 and 89. By analysing multiannual data on harvest deadlines and qualitative parameters of grapes from different regions of Croatia and comparing them with climate data for the same period, we found that the main climatic components affected grape production. In addition, the meteorological data of the Croatian Hydrometeorological Institute also identified trends in Huglin’s index, index sum of the effective temperatures according to Winkler, cold night index and the average air temperature index in the vegetation, for the period 1961-2018. Maps of the four agroclimate indices in 1989-2018 and comparisons with the reference period 1961-1990 indicated climate change over the last 30 years. Due to the increase in the Huglin index of 200 -300°C throughout Croatia, it is possible to change the grapevine varieties in continental Croatia, i.e. planting black wine varieties that need a greater amount of heat, and the possibility of raising winegrowing plantations of early grape varieties in mountain Croatia below 600 m above sea level. The purpose of this research is to increase the adaptability and reduce the vulnerability of Croatian viticulture related to the impact of climate change on grape and wine production through the revision of existing and possible proposal for the establishment of new wine-growing zones in Croatia.