Considerazioni sintassonomiche sulla vegetazione perenne dei substrati incoerenti dell’Italia meridionale e Sicilia

The results of a syntaxonomic study regarding the vegetal perennial associations with a pioneer character, occurring on loose substrata of different types (screes, gravels, sands, metamorphic and volcanic clasts, etc.), from S Italy and Sicily are given. These plant communities are rich in chamaephytes and hemicryptophytes and occur from the coasts up to the mountain belt. They are referred to the order Scrophulario-Helichrysetalia italici, which is represented by two distinct alliances, as Linarion purpureae, circumscribed to montain and submontain territories, and Euphorbion rigidae, distributed in the coastal and hilly belts. For its remarkable floristic, ecologic and chorologic peculiarities, this order, at the beginning attributed to the class Thlaspietea rotundifolii, is now included in a new indipendent class: Scrophulario-Helichrysetea italici.