The main plant community types of the alpine belt of the Apennine chain

This paper deals with the occurrence of the main plant community types occurring within the alpine bioclimatic belt in the Central Apennines. The study area was represented by three mountain groups, the Gran Sasso, Maiella and Laga mountains. These three mountain chains are those in which, out of the entire Apennine area, alpine vegetation is best expressed. The vegetation has been investigated following the Braun-Blanquet phytosociological approach. During the field work 135 releves were collected. The raw data were further treated with multivariate analysis procedures to find objective clusters on a statistical basis. Several plant community types, belonging to different phytosociological classes, such as Elyno-Seslerietea, Salicetea herbaceae, Thlaspietea rotundifolii, Asplenietea trichomanis, were identified. In particular two new phytosociological associations, Galio-Silenetum acaulis and Potentillo-Festucetum alfredianae, and several new sub-associations are described in this paper. In order to express the occurrence and autonomy of the Apennine alpine bioclimatic belt also in coenological terms, a new Seslerion apenninae sub-alliance, named Leontopodio-Elynenion, is here proposed