Measuring landscape fragmentation in Natura 2000 sites. An application in Sardinia

Landscape fragmentation (LF) is a process where natural and semi-natural environments tend to divide into several smaller separate fragments. LF is largely caused by roads and railways, as well as urbanized areas. The most evident effects of LF consist of isolation of animal and plant species, reduction of biodiversity and loss of connectivity between habitats. Several indicators for measuring LF are available in literature. In this work, we use the connectivity indicator (CIx) for Natura 2000 sites. CIx is part of a more complex indicator - the City Biodiversity Index (CBI), or Singapore Index on Cities’ Biodiversity Index –which is useful for measuring connectivity of natural areas. We apply CIx to Natura 2000 sites, where the Tetrax tetrax (Little Bustard) has its habitat. We (i) consider the Tetrax tetraxas target species in that it is a near threatened species, according to the ‘International Union for Conservation of Nature and Natural Resources’ Red List, and (ii) assess the connectivity between habitats and propose defragmentation measures able to reconnect isolated or scarcely connected patches.