A Fragmentation-Based Analysis of Costa Viola (Southern Italy) Agricultural Terraces

Traditional and historic agricultural landscapes cover a significant part of the Italian territory. For these landscapes, the study of change dynamics over a defined time interval is a crucial aspect to monitor their integrity and cultural value and, on the other hand, to set up appropriate strategies to assess their correct management. Terraced agricultural landscapes play an important role in this framework, given their substantial cultural and social value. Because of their artificial creation, this kind of landscape is subjected to continuous changes over time due to the interaction of natural and human factors. To detect the changes that occurred during a time interval of about 60 years, we adopted a fragmentation-based analysis of the terraced agricultural landscape of Costa Viola (Southern Italy). All analyses were conducted in a GIS environment through the free tool Landscape Fragmentation (LandFrag) and the period investigated goes from 1955 to 2014. We analysed the fragmentation of active terraces during three reference years: 1955, 1989 and 2014. A binary raster-based analysis has been conducted for each year according to five fragmentation classes: core, perforated, edge, transitional and patch areas. The dynamic highlighted by the analyses is characterised by the diminution of core areas, representing a stable landscape with no threat of fragmentation, that passed from 300.20 ha in 1955 to just 11.32 ha in 2014, demonstrating an important tendency towards fragmentation of the landscape leading to a gradual disappearance of traditionally cultivated terraces with an increased risk of landslides.