Short-term changes in key plant communities of Central Apennines (Italy)

Recent changes in species composition and abundance in seven plant communities characteristic of Central-European, Sub-Atlantic and Alpine belts of the Central Apennines (oak and beech forest, dwarf-shrubland, highmountain grassland and alpine tundra) were analysed on the basis of 30 permanent plots.Plots, 1 00-300 m 2 in area, were selected in the Velino Mts.National Reserve and the Gran Sasso and Laga Mts.National Park, at altitudes from 1,000 to 2,300 m a.s.l.For each plot, a phytosociological releve was collected (according to the Braun-Bianquet approach) in 1993 and repeated 6 and 8 years later, in 1999 and 2001.In some cases, a releve collected seven years before (in 1986) was also available.A comparative analysis of changes in species composition, life forms, life strategies and morpho-functional types allowed us to recognise dynamical processes (fluctuation, secondary succassion and degeneration) and an increase in drought-and stress-tolerant species, in some cases probably linked to a general process of climate change.