Il censimento dei pronubi selvatici In Italia, con particolare riferimento agli Imenotteri Apoidei

The census of wild pollinating insects in Italy with special reference to Hymenoptera Apoidea. Preliminary investigation. Within the national research Project AMA (BHE - Bee, Honey, Environment), a study concerning the census of pollinating insects in Italy was carried out. Various research institutions (from Udine, Bologna, Turin, Pisa, Perugia, Rome, Sassari and Catania) have prompted a unique comparative field protocol that allows a multilevel data comparison (between different en¬vironments, cultivations, latitudes etc.). During the first two research years (1997-1998) 5,729 pollinating insects were caught and 75,439 were observed. 296 Apoidea species (one third of the Italian fauna) and 48 Syrphidae species (11% of the Italian fauna) were found. The majority of the caught and observed, insects were honey bees (62%), whereas the remnant consisted of bumble bees (10.2%), Syrphidae (6.8%) and other Apoidea (21%). The numerous data collected suggest that Italy could be divided into two faunistic regions: the central-northern one, with predominance of short-tongued bees (Halictidae) and the southern one, where long-tongued bees prevail (Anthophoridae). The application of the indexes of Shannon-Weaver and Sorenson permitted the characterisation of the census zones and pointed out features and differences between diverse environments. In the census zones of Udine, Sassari and Pisa, the biodiversity of apoidea recorded in the agroecosystem (cultivated) resulted higher than that of the mixed ecosystem (composed of cultivated and natural zones). These particular results seem to indicate a sustainable agriculture management.