Does forest strict protection work for plant? Insights from a multifaceted diversity approach in an Italian national park

The establishment of protected areas is an effective strategy to mitigate the global loss of forest diversity caused by human activities. However, the challenge is that not all measures of diversity are equally informative, and protected areas range from strict to sustainable exploitation. We explore how different facets of plant diversity change across strict protection and managed regimes in the forest Casentinesi National Park (Northern Apennines, Italy). We selected 28 beech (Fagus sylvatica L.) forest plots in strict protection (n=14) and managed (n=14) areas. In each plot of 30m×30m, we recorded the presence of vascular plant, and measured specific leaf area and clonal traits of dominant species. We measured taxonomic, functional, and phylogenetic indices. We used Linear mixed models to assess the effect of the protection regime, non-metric multidimensional scaling (NMDS) and indicator species analyses to assess differences in species composition. Strictly protected forests had a significantly higher ratio of specialist species and a higher functional richness of clonal strategies. Different indicator species and NMDS reflected species composition differences. Species richness is an ineffective indicator of changing diversity between different protection regimes. Strict protection impacts forest plant assemblages and functions, promoting habitat specialist species and functional diversity.