New insight on Mediterranean and sub-Mediterranean syntaxa included in the vegetation prodrome of Italy

The Italian Vegetation Prodrome (IVP), implemented on behalf of the Ministry of the Environment and Protection of Land and Sea (also known as MATTM) on the basis of two agreements entrusted to the Italian Botanical Society, has been drawn up to the lower level of suballiance. In the current paper, the syntaxonomical choices adopted in the description and the typification of the new syntaxa are explained through eight main conceptual issues. Among these, there are several Mediterranean and sub-Mediterranean syntaxa, which contribute to improve knowledge of the phytocoenosis biodiversity of these biogeographic areas. Indeed, these Mediterranean and sub-Mediterranean territories are the most important European areas in terms of flora, vegetation and habitats. In the past, the syntaxa of these bioclimatic and phytogeographic areas were mainly included in classes widespread over Europe and in hierarchical levels that are, in our opinion, inappropriate for describing their floristic and phytocoenotic richness. Therefore, we decided, in some cases, to raise their hierarchical level in order to promote a better and more appropriate syntaxonomical classification. The definition of such syntaxa is the result of a research carried out on various aspects of the flora, ecology and dynamic features of the plant communities; they have often considered large geographical territories, wider than Italy and, sometimes, even Europe. The case study of some syntaxa belonging to the classes Euphorbio paraliae-Ammophiletea australis, Sarcocornietea fruticosae, Festuco valesiacae-Brometea erecti, Trifolio medii-Geranietea sanguinei, Rhamno catharticae-Prunetea spinosae are shown.