Distribution of the major forest tree species in Turkey within spatially interpolated plant heat and hardiness zone maps

Abstract

In disciplines such as agriculture, forestry and horticulture, it is customary to make use of various hardiness zone maps intended for the selection of the plant species to be cultivated within specific regions. The most widely used of these maps is the USDA Plant Hardiness Zone (PHZ) map. Recently, the American Horticultural Society also created the Plant Heat Zone (AHZ) Map. PHZ and AHZ maps have not yet been produced for Turkey. To overcome deficiencies of these maps and compare the distribution of major forest tree species over these zones, data from 260 meteorological stations recorded during the period from 1975-2008 and 458 144 forest stand-type polygon centroid data were used. PHZ and AHZ maps were created through the interpolation of meteorological data using the regularized spline with tension (RST) method. According to the interpolation results, there are 7 PHZs (4-10) and 8 AHZs (2-9) in Turkey. Finally, the distribution of 15 major forest tree species over these zones was investigated. The most commonly detected species were distributed among PHZs 5 and 10 coincided with Juniperus spp., Quercus spp. and Abies spp., and the species found between PHZs 5 and 10 were those exhibiting the most extensive distributions. Pinus brutia and Quercus spp. were found to be the most widely distributed species among the AHZs.