Tree-ring chronologies of Pinus sylvestris from Burabai Region (Kazakhstan) and their response to climate change

Abstract

Pinus sylvestris L. (Scots pine) is the main forest tree species in Burabai National Park. Trees here grow under continental climate conditions. There are no dendroclimatological studies based on Scots pine of this region. The purpose of this study was to find the relationships between tree-ring widths and climate. For this purpose, a total of 176 cores from 100 Scots pine trees were collected. After measuring tree-ring widths, standard chronology building methods were used, and three site chronologies were constructed. Correlation coefficients between tree-ring widths with temperature and precipitation were calculated. Precipitation from October of the previous year to July of current year had a positive influence on tree-ring widths and August-September precipitation have the opposite effect. Temperature in the winter had positive effect for tree-ring growth but significantly negative during summer. Effects of climate changes on tree-ring widths were observed. The variation and sensitivity of tree-ring widths increased after 1940s. An increasing trend in precipitation, temperature, and tree-ring widths were clearly observed. In conclusion, tree-rings of Scots pine in Burabai are highly sensitive to growing site conditions and are affected by climate changes.