Vývoj vybraných zmiešaných ihličnato-listnatých porastov v režime bezzásahovosti

The climate change has an adverse impact on tree species and forest stands. Different tree species tolerance and changes in tree species composition are considered as one of the climate change consequences. The paper deals with assessment and comparison of tree species composition and basal area increment in mixed (spruce-fir-beech) stands, which were left to self-thinning during 45–55 years. The large-scale experimental basis of older thinning permanent research plots established, in the past, in mixed stands situated in the 5th and 6th altitudinal forest zone was used in the research. At the same time the detected changes were compared to long-range goal and tree species models specified for a given forest type. The results showed increased proportion of beech and sycamore maple contrary to decreased share of fir and spruce. At the same time, fir also recorded the highest percentage of loss by self-thinning. The comparison of the current tree species composition with the models showed slight differences in all areas in favour of spruce at the expense of beech. Similarly, the basal area increment of beech was the highest everywhere.