A COMPARISON OF STRUCTURAL CHARACTERISTICS AND ECOLOGICAL FACTORS BETWEEN FOREST RESERVES AND MANAGED SILVER FIR - NORWAY SPRUCE FORESTS IN SLOVENIA

摘要

In order to examine ecological, floristic and structural differences between the forest stands of managed and unmanaged silver fir - Norway spruce forests (Bazzanio trilobatae-Abietetum albae), twelve sample plots (25x25 m) were established in forest reserves and managed forests. Within the plots, subplots and microplots we conducted phytosociological and pedological surveys, analyses of the stand structure, natural regeneration and estimation of solar radiation. We determined that there are no significant differences in floristic composition and ecological factors between managed forest and forest reserve stands. The only variables that were significantly different were the solar radiation variables (ISF; TSF; DSF), vertical structure (cover indexes (CI)) and stand basal area. Small differences in the composition and the structure of the vegetation indicate that, as far as ecosystematic changes are concerned, managing these forests is not as significant as the soil conditions. Solar radiation had a major influence on natural regeneration. Indirect solar radiation seemed to be more important than direct solar radiation. We found a statistically significant positive correlation between silver fir and Norway spruce regeneration and indirect solar radiation and confirmed that the management of light is a significant factor in the management of regeneration. Another trend that was detected was an increase in the number of beech, which will have quite a large proportion in the upper tree layer of the next generation, especially in forest reserves.