Our paper presents a comparison of historical data concerning the distribution of forest communities in the Sowie Mountains in southwestern Poland in 1968-71 with material collected by the authors between 2009 and 2013. The analyses were performed using geographic information system software. The archival vegetation maps were digitized, and the layer of the current distribution of forest communities was applied afterward. Archival data indicated that, in the study area, spruce monocultures of anthropogenic character predominated, occupying 90% of forest area. The obtained results suggest that regular forest management conducted within the study area has surprisingly contributed to an increase in the area of forest communities of the Querco-Fagetea class from 766 to 1,579 ha (more than 100%) over the last 45 years. The largest rise in the area of studied communities was observed on meso-oligotrophic habitats, and was reflected in the increase of the area of acidophilous beech forests, representing Luzulo luzuloidis-Fagetum association (habitat 9110 protected in the European Union), from 168 ha to1,064 ha. There was a minor decrease in the area of submontane riparian forests Carici remotae-Fraxinetum (habitat 91E0); the area of mesotrophic beech forests Galio odorati-Fagetum (habitat 9130) seems to be stable. Approximately 72% of deciduous forests in the study area have retained their spatial cover for 45 years.
The newly created forest communities are deprived of a number of essential elements of the structure, primarily dead wood, including lying trunks and trees. The lack of these features does not allow us to assess the status of these ecosystems as entirely satisfactory. However, the possibility of converting Picea abies monocultures in deciduous forests of the Querco-Fagetea class under regular forest management should be considered beneficial to the conservation status of forest ecosystems of mountain areas of Central Europe.