Influence of climate on radial growth of black pine on the mountain regions of southwestern turkey

Abstract

In this study, we identified the most important climate factors affecting the radial growth of black pine at different elevations of the mountain regions of Southwestern Turkey (Sandiras Mountain, Muğla/Turkey). We used four black pine tree-ring chronologies, which represent upper and lower distribution limits of black pine forest on the South and North slopes of Sandiras Mountain. The relationships between tree-ring width and climate were identified using response function analysis. We performed hierarchical cluster analysis to classify the response functions into meaningful groups. Black pine trees in the mountain regions of Southwestern Turkey responded positively to a warmer temperature and high precipitation at the beginning of the growing season. As high summer temperatures exacerbated drought, radial growth was affected negatively. Hierarchical cluster analysis made clear that elevation differences, rather than aspect, was the main factor responsible for the formation of the clusters. Due to the mountainous terrain of the study area, the changing climatic conditions (air temperature and precipitation) affected the tree-ring widths differently depending on elevation.