The climate in Slovenia began to change in the 1980s. These changes were and still are caused by increased average annual temperatures, reduced annual rainfall, more heat waves and consequently more droughts. Spruce is losing its share in the growing stock at the expense of weakness due to drought stresses and consequent attacks by beetles, especially on sites where it has been artificially introduced and accelerated in the past. As spruce is still one of the most economic important tree species in Slovenia, we wanted to use dendrochronological analysis to verify the influence of the described climatic factors on its growth in lowland locations. We performed an analysis of spruce thickness increment at 6 different locations in the lowlands of Slovenia and processed the data with the help of various computer programs (ATRICS, PAST-5, CDendro) at the Slovenian Forestry Institute in Ljubljana. In all cases, we observed the effects of climate change, which are reflected as a negative effect of temperatures and a positive effect of precipitation on the radial growth of spruce, which indicates an increase in the impact of drought stress on tree growth. By analyzing the sliding correlations, we proved that the influence of the described climatic factors increases with the approximation of the present.
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