Changes in precipitation extremes for the Basilicata region, southern Italy, have been analyzed using data from 55 precipitation stations with complete daily time series during the period 1951-2010. All the series were submitted to quality control assessment and homogenization. To detect possible trends the time series analysis was performed with the Mann-Kendall non-parametric test. The annual and seasonal total precipitation underwent a general downward trend over the period 1951-2010 mainly due to the autumn-winter decrease of precipitation, although the tendency for the last decade is clearly positive. The precipitation intensity shows a general positive trend, mainly due to the upward trend of spring. The dry spell mean has increased throughout the region over 1951-2010, even if a really important opposite trend characterizes the last decade. The wet spell mean has decreased throughout the region from 1951 to 2010, although a strong inversion of tendency has been recorded in the last 10 years. Trends in the extreme daily precipitation have indicated a general downward tendency, mainly during the summer season. The analysis of multi-day sequences of moderate to heavy rainfall has indicated a corresponding increase in their frequency and intensity, especially in the last decade. The overall results indicate a present hydroclimatic regime characterized by an increase in total rainfall and precipitation intensity and a small decrease in dry spell lengths. The positive change in precipitation magnitude is due to multi-day extreme precipitation rather than to single-day precipitation. This last observation is very important for its huge hydrological impact on the environment. In Basilicata, the increase in intensity/frequency of multi-days extreme events has led to the growth of severe flooding and landsliding events, not only in autumn and winter, but even in the early spring.

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The Tursi-Rabatana historical site is very representative of the cultural heritage of Basilicata, Southern Italy. Morphological evolution of the landscape is characterized by very intense erosive phenomena such as landslides, deep gullies, rills, and piping, which affect the perimeter of urban settlements and threaten the conservation of these sites. Rainfalls and the lithology of the substratum are the main factors to which the landscape evolution is linked, triggering landslide and linear erosion phenomena. Climate analysis carried out during the last century showed an increasing trend in the rainfall intensity over extremely short periods. This condition also induced an increase in the vulnerability level of the slopes. Integrated analysis between territorial data (geology, geomorphology, climate) and historical documents showed that, at least from the last century, the geomorphological hazard has been accentuated by the intense human activity of cave excavation along several fronts under the present urban area. The geophysical investigation also permitted the mapping of shallow caves and tunnels in the subsurface reconstructing the multilevel complex hypogeal system. This work also produced evidence that the human interventions occurring during the historical period have been a determining factor in increasing the hazard level and accelerating the preexisting morphological processes.

A 1:10,000 scale landslide inventory map has been prepared for the Basilicata region (southern Italy) through extensive geomorphological analyses based on aerial photo-interpretations and field surveys. The study area (about 8000 km 2) includes different morpho-structural domains of the southern Italian Apennines, and our results suggest that mass movement processes are mainly related to the intrinsic fragility of the landscape, which is featured by high relief and widespread outcrops of clay-rich deposits. As a matter of fact, the landslides of the inventory map cover about 4.8% of the surface area of the Basilicata region, whereas the total percentage of the area covered by the landslides reaches a value of 7.7%, if one considers also the landslides surveyed in previous works.