Patterns and environmental drivers of compositional variability of the habitat 6210 (*) in the Reatini Mountains (central Apennines – Italy)

The Habitat 6210(*) includes temperate, dry to semi-dry, hemicryptophytic grasslands of secondary origin, belonging to the class Festuco-Brometea. These grasslands host a very high plant diversity, are very rich in endemic taxa and provide key ecosystem services. Nevertheless, the decline in the extent and connectivity of these grasslands, particularly in mountain areas, has been repeatedly documented across Europe, constituting a major conservation problem. In mountain areas, this decline is mainly due to the colonization by woody species following land abandonment. Since environmental conditions strongly interact with changes in management in determining the patterns and rates of successional processes, we aim at identifying which environmental drivers influence the habitat shifts in vegetation composition and structure in support of conservation decision on the Habitat. We performed 64 phytosociological relevés in the Reatini Mountains, within the 6210(*) “environmental range”, and associated to each relevé broad scale environmental (e.g. lithology and annual rainfall) and topographic variables (e.g. altitude and slope). The data was explored through multivariate analyses. Our results show that: i) within the “environmental range” of 6210(*) different grasslands occur, some of which may not be referred to the Habitat, and ii) the environmental variables that drive the variation between habitat types differ from those causing the within-habitat heterogeneity. This variability should be taken into account in the monitoring and conservation plans in order to preserve or enhance the conservation status of this Habitat.