Phytosociological analysis in Sardinian Mediterranean temporary wet habitats

The aims of this research were to contribute to the knowledge of the Mediterranean temporary wet habitats vegetation and to investigate the spatial distribution and the temporal successions of plant communities under different hydrological regimes in North Western Sardinia. The vegetation was sampled in temporary wet habitats located in large depressions (temporary ponds), in small depressions in patchwork with the vegetation dominated by Myrtus communis (waterlogged soils) and in rocky outcrops (rock pools). Three belts were recognized in temporary ponds: a central belt, an intermediate belt, and an outer belt. Overall I I associations and subassociations were identified, within 4 syntaxonomic classes: Potametea, Isoeto-Nanojuncetea, Isoeto-Littorelletea and Phragmito-Magnocaricetea. Four new associations have been described: Isoeto tigulianae-Callitrichetum brutiae, Romuleo requienii-Isoetetum histricis, Apio crassipedis-Elatinetum macropodae, and Lythro hyssopifoliae-Crassuletum vaillantii. Moreover, within the Preslion cervinae alliance of the lsoeto-Nanojuncetea class, a new Tyrrhenian suballiance Apienion crassipedis, has been established, for which the typical association is the Apio crassipedis-Isoetetum tigulianae Biondi & Bagella 2005 corr. hoc loco. Aquatic vegetation was found in the central and intermediate belt of the temporary ponds and within the rock pools. Late winter-spring amphibious communities were present in almost all temporary wet habitats. Summer plant communities were found exclusively in the central belt of temporary ponds