A comparative analysis of recent changes in Dinaric uneven-aged forests of the NW Balkans

Long-term dynamics of selection (plenter) forests and corresponding virgin forests in NW Balkan countries (Slovenia, Croatia, Serbia, Bosnia and Herzegovina and Montenegro) were examined by assessing changes in diameter structure, stand volume and tree species composition. The parameters were aggregated at the landscape spatial scale, and the intensity of changes in diameter structure and tree species composition was measured by the index of dissimilarity. It was hypothesized that structure and composition of selection forests and virgin forests remained rather stable over several decades. Our study revealed pronounced dynamics in the observed parameters. However, these changes were divergent; in most study areas, increases of stand volume and large-diameter trees were observed, and in selection forests, the proportion of silver fir in the total stand volume decreased in three study areas and increased in two. Changes in diameter structure and tree species composition of the virgin forests were relatively less pronounced. In selection forests, an increasing proportion of mid-shade-tolerant Norway spruce and a constant proportion of light demanding sycamore, which is almost absent in virgin forests, were observed. The great capacity of the selection system to create stands of different structure and composition may be an important advantage in increasingly unpredictable economic, social and environmental conditions.