Growth responses of Picea abies to climate in the central part of the Ceskomoravska Upland (Czech Republic)

The aims of the study were to determine the effect of temperatures and precipitation on the ring width and to compare the results with the results of previous studies conducted in other mountain ranges of the Czech Republic. The research was performed in the central part of the Ceskomoravská Upland in the vicinity of Herálec municipality in selected 70- up to 110-year-old spruce stands at altitudes from 680ma.s.l. to 779 m a.s.l. Measuring of tree-ring widths and synchronization of individual ring series were conducted in PAST4. The age trend was removed by ARSTAN and climatic effects were modelled in DendroClim2002. The correlation of tree-ring width with monthly precipitation is positive and statistically significant for July of the previous year and for the entire summer period from June to September of the current year. The correlation of tree-ring width with mean monthly temperatures is negative and statistically significant for July and September and positive and statistically significant for October of the previous year. Negative correlation was also found for temperatures of the entire summer period from June to September of the previous year. The regional tree-ring chronology mainly shows two periods of highly reduced increment: from 1992 to 1996 and from 2003 to the end of the analysed period. The results thus confirm the hypothesis that the tree-ring width is in positive correlation with summer precipitation and negative correlation with summer temperatures. Also the results of the habitual diagnostics have shown a relatively low degree of crown transformation which indicates a weak or short-term stress load.