EN
The paper presents the analysis of changes in two beech forest communities in the Kołowskie Parowy nature reserve (NW Poland). Within 21 years the frequency and cover of most species significantly decreased, including typical taxa for shady deciduous forests. Analysis of ecological indicator values showed that species richness is strongly correlated with light availability. The results suggest that passive protection promoted in Puszcza Bukowa forest brings negative effects for vascular plants biodiversity