Status and trends of biodiversity, including benefits from biodiversity and ecosystem services
San Marino is an enclaved microstate (61 km2) located on the Italian peninsula, to the northeast of the Apennine Mountains, featuring small steep valleys and creeks and spectacular limestone cliffs. Despite its small size, the country contains a high level of biological, geological and landscape diversity. Twenty-one percent of its territory is assessed as urban; 41% agricultural (mainly arable lands, orchards, vineyards and olive groves); 16% woodlands (predominantly oaks and other broadleaves); over 17% shrublands and similar lands; 4% badlands; while less than 1% is covered by rivers. Due to the presence of several ecotone belts, different vegetation types and a mosaic of human and wild landscapes, a large variety of species of flora and fauna exists in the country.
Small portions of the country have conserved natural landscape and good ecosystem functionality. A high level of ecosystem heterogeneity is present in certain badland zones (e.g. in the valleys of Fosso di Ca’ Chiavello and Fosso delle Bruciate and in the Torraccia zone), while good ecosystem functionality is particularly linked to the water network (upper basin of the San Marino Torrent).
Fragmentation of the landscape is an important phenomenon and closely linked to intensive land use although there are still areas where the dynamics of fragmentation are barely noted. The entire forestry system must be protected; incentives are needed to increase the functions of the system, including its service as a carbon reservoir in compliance with the Kyoto Protocol, among other functions. Suitable strategies for preserving calanques are also needed.
In addition to the loss of soil and change in its intended use, with consequent modification and fragmentation of habitats caused mainly by a high rate of widespread urbanisation, another major threat faced by the small country, which currently constitutes an immediate danger to the preservation of habitats and species, is the alteration of ecosystems of running waters, due to the dispersion of mostly organic waste and modification of the natural physical structure of riverbeds.
All habitats and indigenous species of fish in running water can be considered endangered and some of them critically endangered. The South European Nase (Chondrostoma genei
) has not been found since the 1990s and can be considered extinct in the territory.
Main pressures on and drivers of change to biodiversity (direct and indirect)
Since the national territory has a very limited extension (6,119 ha) and is totally located within the Italian peninsula, it is inevitably subject to environmental changes, pressures and the threats that, on a large scale, affect biodiversity in Italy.
However, in the small country of San Marino, simplification of agro-ecosystems, use of pesticides, chemical pollution and construction of specific infrastructure do not currently represent a serious problem; instead the direct consequences of the current rate of urbanization include the loss, fragmentation and erosion of habitats and impairment of their ecological and functional roles, with several negative effects on the survival of populations and species, soil permeability, temperature rise and hydrogeological balance.
Also, alteration of the physical structure of the waterways, organic pollution from sewage and reduction of water flow due to anthropic exploitation and climate change constitute an immediate problem to the preservation of habitats and species.