Dendrochronological Potential of Juniperus foetidissima Willd in Central Anatolia, a Semi-arid Region of Turkey
Keywords:Climate-growth relationship, Long-lived tree species, Mean sensitivity, Tree-ring chronology
The dendrochronological potential of Juniperus foetidissima, growing in central Anatolia, was assessed. Raw, standard, and residual tree-ring chronologies were prepared for J. foetidissima trees in the Eskişehir region using classical dendrochronological methods for the period between 1875 and 2014. All the chronologies were statistically relevant, and the running correlation, expressed population signal, and mean sensitivity values in the residual tree-ring chronology were within the given limits. Therefore, the residual tree-ring chronologies were used to assess the climate-growth relationship. The relationships between tree-ring width growth and climate variables (mean temperature, monthly sum of precipitation) were investigated using response function analysis (moving windows correlations) in the R platform. Positive or negative relations were found between the residual tree-ring widths and the monthly precipitation and mean temperature, but with low coefficient values. The tree-ring width growth showed a significantly negative response to precipitation in August of the current year for the period in 1977-2001 and 1978-2002 and significantly positive to temperature in June of the current year for the period in 1971-1995, 1972-1996, and 1993-1996. In conclusion, despite some problems with cross-dating, J. foetidissima can generally be used for dendrochronological research and is suitable for developing long-term chronologies.