URBAN-DEVELOPMENT AND INSECT BIODIVERSITY OF THE ROME AREA, ITALY

Rome, Italy's largest city, has about 3 million inhabitants and covers an urban surface area of 360 sq. km. The insect fauna of this area ha s been the object of research since the second half of the 19th centur y. Rome is one of those rare cases in Europe where urban expansion in the last century took place on an area, the 'Campagna Romana', which h ad been practically uninhabited. A study based on a critical revision of the entomological literature published from 1850 to nowadays, toget her with other unpublished material has evidenced the presence and the microdistribution of about 5200 species belonging to not less than 35 6 families. Such information, although so vast, is however still incom plete. Documentation for groups such as Heteroptera, Coleoptera, Dipte ra, Macrolepidoptera and Hymenoptera Aculeata, which have traditionall y been studied by local entomologists is quite complete, but groups su ch as Collembola, Psocoptera, Phtiraptera, Thysanoptera and Homoptera are still poorly documented. From a preliminary global analysis of dat a collected, it can be clearly seen that from the end of the 40's ther e has been a general impoverishment of the species, particularly in th ose communities linked to wetlands. Aspects Linked to urbanization whi ch have influenced, or influence the insect fauna are also evidenced: 1) environmental modifications which took place in the last one hundre d years on a local scale (the rapid urbanization of the city from 1870 onwards due to its role as capital of Italy) and on a regional scale (land reclamation and progressive human impact on the 'Campagna Romana ', modifications to the flow of the river Tiber and its tributaries, c hemical control of culicides as vectors of malaria); 2) the presence o f large central green areas and greenways (historical villas and archa eological areas) and their role in the conservation of biodiversity. ( C) 1997 Elsevier Science B.V.