Climate Classification in Turkey: a Case Study Evaluating Holdridge Life Zones

Abstract

The Holdridge life zone (HLZ) method is applied to map potential vegetation types in Turkey. The HLZ map is compared to a map of actual vegetation in order to assess the degradation status of vegetation in Turkey. Data required to identify HLZ classes are provided by the General Directorate of Meteorology, while the current vegetation status is estimated with data provided by the General Directorate of Forestry. After weather data are cleaned and missing values are replaced, the HLZ type is estimated for each station, and then thematic maps are created using the ArcGIS software. The study reveals that there are 12 HLZ types in Turkey. The three dominant types are as follows: cool temperate steppe, warm temperate dry forest, and cool temperate moist forest. In regions where physical geographical controls change in short distances, the biodiversity is greater, and linked to this, the HLZ diversity also appears to be greater. Comparing the identified life zones to the actual vegetation, in some areas, remarkable mismatches can be found. Although, in some regions, the life zone type is consistent with the land cover type, in some narrow areas, the potential vegetation does not reflect features of the current vegetation cover. Considering limitations and capabilities of the assessment approach used in this study, we think that the incompatibility between actual and modelled vegetation types in the eastern region of Turkey is caused by the intensive landscape use. The goal of this research is to support future bioclimatic studies and land use management strategies.