According to the yearly reports of Slovenia Forest Service, the percentage of Norway spruce in Slovenian forests is declining. This is because of the greater frequency of natural disasters and, presumably, climate change. Spruce is even more sensitive in Slovenia as it is at the edge of its natural areal. Since spruce is an important economic species, it is vital to research its future trends. We conducted a dendrochronological analysis of the spruce's radial increment at eight different plots throughout Slovenia. The plots selected were diverse: some were natural spruce stands; in some the spruce was intoduced anthropologicaly in the past for economic reasons, or its natural share in stands was increased. We took samples of at least 20 trees per plot and examined them in the dendrochronological laboratory using Advanced Tree-Ring Image Capturing System (ATRICS) and different software. We compared the growth in natural spruce stands with the secondary (anthropogenic) ones and found no statistical differences in growth patterns between those two groups. However, we found some evidence for climate change, affecting growth on some of the selected sites. Analysis of pointer years suggests that extreme events are more common in the last 30 years.
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