Synecology, syntaxonomy and syndynamism of terrestrial bryophyte communities of southern Sicily

This work presents the results of a phytosociological study of terricolous bryophyte communities, conducted in southern Sicily. The area surveyed is a wide territory included in the communes of Mazzarino, Niscemi, Acate, Vitt oria, Mazzarrone, Caltagirone and San Michele di Ganzaria. The oak woods (Q uercetea ilicis) and their degraded formations (evergreen shrubs, garigues, meadows) are widespread in the area. The analysis revealed Il different co mmunities. 10 are referring to class Barbuletea unguiculatae: Riccietum atr omarginato-lamellosae, Trichostomo crispuli-Aloinetum aloidis, Astometum cr ispi, Acaulo fontiqueriani-Bryetum gemmilucentis ass, nova, which occurs on sandy siliceous soil in clearings of cork-oak woods, Riccio nigrellae-Oxym itretum paleaceae, Gymnostomo viriduli-Southbyetum nigrellae, Pleurochaeto- Cheilotheletum chloropi, Rhynchostegietum megapolitani, belonging to the or der Barbuletalia unguiculatae; while Pterygoneuretum subsessilis and Crossi dio crassinervis-Aloinetum aloidis to order Tortulo brevissimae-Aloinetalia bifrontis. One community is referring to class Cladonio-Lepidozietea repta ntis: Rhynchostegiella litorea community, which grows on humiferous soil in mesophilous microclimate conditions within evergreen sclerophyll woods. In addition to the floristic and ecological description of the mentioned comm unities, data are given about the high vegetation and the main edaphic para meters of the sites. Finally, a succession pattern is proposed for the comm unities described relating to the microenvironmental gradients of xerophily and the soil depth.