MODELS TO DETERMINE THE THERMAL SUITABILITY FOR EUROPEAN PEAR ORCHARDS IN ROMANIA
Models to determine the climatic suitability of an area for fruit crops using daily temperatures were tested by different authors. Many of its compares the major thermal physiological known ranges of the species (absolute and optimum maximum and minimum temperature tolerated by the crop) with the geographical distribution of climate variables. The objective of this work was to develop models that would identify areas where climate conditions are likely to be suitable for pear orchards over Romania. Compared to the model of Bowen and Hollinger (2004), which used daily temperature values we generated using sinusoidal functions hourly temperature values based on both average temperatures and extreme daily ones (1980-2009), recorded with a probability of 25% for minimum and 75% for the maximum values. The models identified the areas where temperature conditions are likely to be suitable for pear orchards over Romania. High risk areas to winter frost (below -28°C) were depressions from Transylvania and the north-eastern region of the country (north of Moldavia). The most frequent climatic accidents of this kind occur in Eastern Transylvania at Miercurea Ciuc, Brasov, Bistrita, at an interval of 2 years, 6 and 11 years, respectively. Considering the growing season length, the most favourable zones with the longest season of vegetation slightly below the maximum limit of the species (270 days), are in the south and south-western part of Romania. The average value of the duration of the growing season for the 29 cities was 238 days and the maximum amplitude of 31 days. The biggest values of the annual sums of hours with tempera-tures ranging from optimum minimum (20°C) to optimum maximum (35°C) for European pear were registered in the south, extreme south-western and south-eastern part of Romania. These are the most favourable zones for pear crop growth and fruiting. In any town of Romania were not recorded hourly temperatures above the optimum maximum of the species (35°C).
Chiţu, E., Chiţu, V., Sumedrea, D. and Mateescu, E. (2013). MODELS TO DETERMINE THE THERMAL SUITABILITY FOR EUROPEAN PEAR ORCHARDS IN ROMANIA. Acta Hortic. 981, 741-748
Pyrus communis, zoning, frost, optimum, maximum and minimum temperature