Biodiversità ed emergenze floristiche nelle aree archeologiche romane

Biodiversity and floristic emergencies in Roman archaeological areas – The flora of the main Roman archaeological sites results particularly rich in species, counting 672 taxa, that corresponds to over 50% of Rome’s spontaneous flora. Many species are very interesting, as new for the city (Damasonium alisma subsp. alisma, Echium parviflorum, Neatostema apulum, Orobanche picridis, Arenaria serpyllifolia, Gnaphalium luteo-album, G. sylvaticum, Oenanthe silaifolia var. media, Poa trivialis subsp. sylvicola, Cuscuta planiflora, Romulea columnae subsp. columnae, Stellaria cupaniana, Trifolium striatum subsp. tenuiflorum), or very rare in the urban area (Polygonum aviculare, Antirrhinum siculum, Myagrum perfoliatum, Urtica pilulifera etc.) or in Latial region (Parietaria lusitanica subsp. lusitanica, Trachelium caeruleum subsp. caeruleum, Artemisia annua). Some of these moreover belong to the Red Regional List of IUCN or result as protected species in Latium. These data underline as Roman archaeological areas represent important refuge sites for floristic entities that in other urban areas loose their habitat. The biological spectrum shows the prevalence of therophytes (45%), followed by hemicriptophytes (29.3%), in accordance to the pedo-climatic characteristics and the use and the type of management adopted in these areas. Chorological analysis confirms the important role played by the climate, in the dominance of Mediterranean species (40,7%), and by human impact, in the high number of widely-distributed species (33.8%), above all in the central archaeological sites. Anyway the exotic component results low (8.3%), underling the importance of these areas in urban ecosystem for the conservation of native spontaneous flora.