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The present work aims at identifying the location of recent debris-flow-dominated alluvial fans at a regional scale in Calabria (southern Italy). Here, alluvial fans widely occur as both tributary junction and mountain front types and represent a potential hazard to human settlements and transportation links near or on them. The alluvial fans inventory map at 1:250,000 scale was obtained by means of a stereoscopic interpretation of aerial photos shot in 1954–1955. To establish the activity of the detected alluvial fans, recent documentary evidence (scientific reports, local newspapers and journals, and Internet blogs) on debris-flow events and historical satellite imagery available on Google Earth, covering the period 2001–2014, were analysed. Subsequently, the activity of the alluvial fans over the last 60 years has been divided into four classes. A total of 1170 alluvial fans have been mapped, 545 (46.58%) of which have been active over the last 60 years. The alluvial fans with a length from apex to toe < 200 m predominate, constituting 70% of the total. In the feeder basins, the dominant lithologies are represented by medium to high-grade metamorphic rocks and igneous rocks, gravel and debris and, shales and low-grade metamorphic rocks. Finally, the inventory map shows that 103 settlements are located on alluvial fans, 18 of which are active or have been active during the last 60 years. This map is a useful tool for land planning policy and for the assessment of risk deriving from debris-flows on the alluvial fans of the Calabria region. [ABSTRACT FROM PUBLISHER]

In the last decades, building damage caused by landslides in urban areas has increased due to the rapid growth of urbanization even on landslide-prone slopes. This work presents the analysis results of landslide damage evolution by means of a macrodamage index in relation to the characteristics of landslides. The study area is located in southern Italy, and is affected by slow-moving landslides, which, over time, have caused relevant effects on the buildings. A series of geological and geomorphological studies and field surveys, supported by monitoring via conventional geotechnical techniques, allowed us to classify four categories of landslides based on the following criteria: landslide movement, type of material and estimated depth. Detailed field surveys aimed at evaluating distribution and evolution of the damage to buildings located within and near the unstable area were carried out in 2005 and 2011. The evaluation of the macrodamage index in two different years enabled us to directly correlate the features of the landslide categories and their effects on the urban fabric. [ABSTRACT FROM AUTHOR]