Predicting future shift of drought tolerance zones of ornamental plants in Hungary

Climate of Hungary, Central Europe, is predicted to undergo substantial aridification by 2100 due to the decrease of precipitation in the summer season. Dendrology and ornamental plant application require adaptation to these climatic changes. This paper aims at giving guidance for landscape architects, dendrologist, and horticulturists by providing spatial predictions on both drought tolerance zones of ornamental plants and the amount of needed irrigation (i.e., precipitation deficit). Future climate of two prediction periods (2025-2050, 2071-2100) are compared to that of the reference period (1961 1990), based on regional climate model RegCM3 driven by IPCC SRES scenario A1B. Three drought tolerance zones are studied that are found to shift northward in the future. It is predicted that, by the end of the 21st century, the less drought tolerant ornamental plants applied countrywide nowadays will lose the chance to survive without considerable irrigation efforts in Baranya, Bks-Kiskun, and Csongrad counties (southern Hungary). Since nursery production is now located in those regions that may be mostly affected by aridification, it needs planning adaptation measures.