Pattern of floristic variation on a montane beech forest in the central Apennine (central Italy)

Climate, history and human land use have a strong influence on the distribution and floristic composition of beech forest communities. In the last 50 years, the decrease in human activities has led to the resumption of reforestation dynamics, so a certain variability in floristic composition is expected. We aim to identify the causes of local floristic variability in different stands of beech forests, integrating floristic, structural and ecological analysis. Cluster analysis and Indicator Species Analysis (ISA) were performed to highlight floristic differences; the clusters obtained were compared through environmental and topographic variables, Ellenberg indicator values, life forms, Social Behaviour Types (SBT) and structural parameters. The species heterogeneity derives from a climatic and edaphic gradient. Two main types of beech forests were recognized: a microthermal one, placed at higher altitudes and cooler aspects (Cardamino kitaibelii - Fagetum sylvaticae), and the termophilous one, lying at lower altitudes and warmer aspects (Lathyro veneti - Fagetum sylvaticae). SBT and structural parameters were useful for detecting the effects of dynamic processes of reforestation. The integration of the floristic, structural and ecological analysis led to an accurate coenological overview of the beech forest communities and to the detection of the natural reforestation processes currently ongoing