1. Classification of Croatian winegrowing regions based on bioclimatic indices
Marko Karoglan1, Maja Telišman Prtenjak2, Silvio Šimon3, Mirela Osrečak1, Marina Anić1, Jasminka Karoglan Kontić1, Željko Andabaka1, Ivana Tomaz1, Branko Grisogono2, Andreina Belušić2, Antun Marki2, Željka Prša2, Branimir Omazić2, Damjan Jelić2, Željko Večenaj2, Višnjica Vučetić4, Damir Počakal4, Ivana Vladimira Petric3 , Renata Leder3, Ivan Prša3
1 Faculty of Agriculture, Department of Viticulture and Enology, University of Zagreb, Zagreb, Croatia
2 Department of Geophysics, Faculty of Science, University of Zagreb, Zagreb, Croatia
3 Centre for Agriculture, Food and Rural Affairs of Croatia, Zagreb, Zagreb, Croatia
4 Meteorological and Hydrological Service of Croatia, Zagreb, Croatia
Abstract
The aim of this work was to classify vine growing regions of Croatia using bioclimatic indices. For the analysis of climatic conditions, linear trends of bioclimatic indices were determined using meteorological observations for all available climatological stations located in vine growing regions of Croatia. Analysis were performed for two different climatological periods: and Four commonly used bioclimatic indices were determined: the Winkler index, the Huglin index, Cool night index and Growing season average temperature.
Introduction
Several bioclimatic indices are commonly used in vineyard zoning and in aim to describe suitability of climate of different winegrowing regions. They are also useful metrics to provide the information about climate changes impact on viticulture (Malheiro et al. 2010). The viticultural zoning in Croatia has been established in 1978, and was based on the several factors including climate, soils and topography of Croatian vineyards. In the mean time, we have witnessed that the Earth's average surface temperature has increased by approximately 0,7°C since the beggining of the century. The main goal of this study was to examine the current spatial climate structure of the Croatian viticultural regions, using four standard grape-based bioclimatic indices, such as average growing season temperature (TGS), Winkler indeks (WI or GDD), Huglin Heliothermal Index (HI) and Cool Night Index (CI) which were calculated for two different climatological periods.
Results
Comparison of bioclimatic indices:
A) B)
Materials and methods
Temperatures observation data for 29 meteorological stations located in Croatian viticultural regions were collected for the reference time period ( ) for the present climate according to the World Meteorological Organisation. Beside that, the same observations were collected for the period of last 30 years ( ), in aim to compare the data with the reference period.
INDEX
PERIOD
CLASSES DEFINiTION
Average growing season temperature (TGS) Jones (2006)
April - October
Too cool
˂ 13 °C
Cool °C
Intermediate °C
Warm °C
Hot °C
Very hot °C
Too hot
> 24°C
Growing degree - days (GDD or WI) Winkler et al. (1974)
Region I
˂ 1390
Region II
Region III
Region IV
Region V
> 2220
Huglin index (HI) Huglin (1978)
April - September
Very cool (HI-3)
˂ 1500
Cool (HI-2)
Temperate (HI-1)
Temperate warm (HI+1)
Warm (HI+2)
Very warm (HI+3)
> 2700
Cool night index (CI) Tonietto (1999)
September
Very cool nights (CI+2)
˂ 12 °C
Cool nights (CI+1) °C
Temperate nights (CI-1) °C
Warm nights (CI-2)
> 18 °C
Bioclimatic indices were analyzed for two climatic periods and for each of 29 meteorological stations individually. Results obtained were grouped according to main Croatian viticulture regions and subregions.
The bioclimatic indices were evaluated on the basis of the class levels listed in table.
Conclusion
Significant changes were noticed when comparing recent climatologic period ( ) to the reference climatological period ( ), thus pointing out the presence of climate changes in Croatia. Bioclimatic indices values were compared to those from the other worldwide known winegrowing regions in order to evaluate viticulural potential in Croatia. But, for more precise comparison, more viticultural factors must be included (e.g. soils, precipitation etc.) since the same climatic group does not necessarily mean the same climate. This study provides accurate information needed for the questioning of existing and establishing a new viticulture zoning system in Croatia.
Literature
Huglin P. Nouveau Mode d’Evaluation des Possibilites Heliothermiques d’un Milieu Viticole. C. R. Acad. Agr. France, (1978)
Jones G.V. Climate and Terroir: Impacts of Climate Variability and Change on Wine. In Fine Wine and Terroir- The Geoscience Perspective. Macqueen R.W., and Meinert L.D. (eds.), Geoscience Canada Reprint Series Number 9, Geological Association of Canada, St. John's, Newfoundland, 247 p (2006)
Malheiro A.C., Santos J.A., Fraga H., Pinto J.G. Climate change scenarios for viticultural zoning in Europe. Clim. Res. 43, 163–177. (2010).
Tonietto J., Carbonneau A. A multicriteria climatic classification system for grape-growing regions worldwide. Agric. Forest Meteorol. 124, 81–97. (2004).
Winkler A. J., Cook A., Kliewere W. M., Lider L. A. General Viticulture, (4th ed.), University of California Press, Berkeley, 740 p. (1974).
This research is part of interdisciplinary project VITiculture and CLImate Change in Croatia (VITCLIC)
Founded by through with support of