Geomorphology and GIS analysis for mapping gully erosion susceptibility in the Turbolo catchmen (Northern Calabria, Italy)

This work summarizes the results of a geomorphological and bivariate statistical approach to gully erosion susceptibility mapping in the Turbolo stream catchment (northern Calabria, Italy). An inventory map of gully erosion landforms of the area has been obtained by detailed field survey and air photograph interpretation. Lithology, land use, slope, aspect, plan curvature, stream power index, topographical wetness index and length-slope factor were assumed as gully erosion predisposing factors. In order to estimate and validate gully erosion susceptibility, the mapped gully areas were divided in two groups using a random partitions strategy. One group (training set) was used to prepare the susceptibility map, using a bivariate statistical analysis (Information Value method) in GIS environment, while the second group (validation set) to validate the susceptibility map, using the success and prediction rate curves. The validation results showed satisfactory agreement between the susceptibility map and the existing data on gully areas locations; therefore, over 88% of the gullies of the validation set are correctly classified falling in high and very high susceptibility areas. The susceptibility map, produced using a methodology that is easy to apply and to update, represents a useful tool for sustainable planning, conservation and protection of land from gully processes. Therefore, this methodology can be used to assess gully erosion susceptibility in other areas of Calabria, as well as in other regions, especially in the Mediterranean area, that have similar morphoclimatic features and sensitivity to concentrated erosion

Landslide susceptibility zonation at the regional scale: the Molise case study (Italy)

Molise is an Italian region with a high concentration of landslides. However, an estimation of landslide susceptibility for the entire region has never been officially performed. In this paper, a landslide susceptibility analysis is illustrated based on the implementation of two different statistical methods (bivariate and multivariate). The aim is to obtain a susceptibility map that provides a good representation of the criticality of the study area together with a reliable statistical performance. Various combinations of conditioning factors were tested with the two methods and, based on expert judgment and ROC (Receiver Operating Curve) values, the one obtained through the multivariate approach was selected as the best map

Recent channel adjustments and riparian vegetation: some examples from Molise (Italy)

An integrated geomorphological and ecological approach was adopted to investigate the relation between recent channel adjustments and riparian vegetation evolution by performing a large-scale multi-temporal analysis of channel and land cover features and a study of the present-day floristic setting along the three major river systems present in Molise (Southern Italy), the Volturno, Biferno and Trigno. Our results highlight the major channel adjustments that occurred between 1954 and 2009 consisting in progressive morphological changes, extreme channel narrowing (between 84% and 97%) and moderate to very intense channel incision (between 2 and 10.5 m). These channel adjustments led to the progressive stabilization of most of the formerly active channel systems and were accompanied by substantial changes in the riparian vegetation which now appears largely, but not completely, in equilibrium with the present river dynamics. Major differences may be noted between the studied river reaches in relation to their state of naturalness, floristic richness and differentiation in vegetation types, which appear particularly controlled by the amount of channel incision and human disturbance. Our findings underline the importance of fluvial dynamics and trends in controlling the development and structure of riparian vegetation and the connected ecological status of river system

A deep, stratigraphically and structurally controlled landslide: The case of Mount La Civita (Molise, Italy)

The present paper illustrates the results of an integrated study of a large landslide located on the southern slope of Mount la Civita (Molise, Southern Apennine), an E-W elongated, SSE dipping and 890-m-high monocline carbonate ridge. The upper part of the slope affected by the landslide is largely controlled by strata attitude while its basal part is marked by a strike-slip fault causing the tectonic juxtaposition of the carbonate successions against predominantly clayey flysch units. An integrated study, including geological, geomorphological and geotechnical investigations, was carried out to determine the features of the landslide and to plan further investigation and monitoring. In particular, from 2002 to 2004, Differential Global Positioning System monitoring and core drillings, coupled with inclinometer measurements, were carried out to determine the landslide's kinematics, extent, depth to the surface of rupture and rates of movement. Inclinometer data revealed the presence of the rupture surface at a depth of about 20 m. DGPS monitoring allowed rates of movement up to several tens of centimetres per year to be recorded. The nearby village of Civitanova del Sannio can still be considered at risk due to the landslide, as recent remedial works, consisting mainly of very shallow re-shaping of the slope by blasting and partial filling of trenches, did not succeed in stopping its movement. © 2012 Springer-Verlag.Peer Reviewe

A deep, stratigraphically and structurally controlled landslide: the case of Mount La Civita (Molise, Italy)

The present paper illustrates the results of an integrated study of a large landslide located on the southern slope of Mount la Civita (Molise, Southern Apennine), an E–Welongated, SSE dipping and 890-m-high monocline carbonate ridge. The upper part of the slope affected by the landslide is largely controlled by strata attitude while its basal part ismarked by a strike–slip fault causing the tectonic juxtaposition of the carbonate successions against predominantly clayey flysch units. An integrated study, including geological, geomorphological and geotechnical investigations, was carried out to determine the features of the landslide and to plan further investigation and monitoring. In particular, from 2002 to 2004, Differential Global Positioning System monitoring and core drillings, coupled with inclinometermeasurements, were carried out to determine the landslide’s kinematics, extent, depth to the surface of rupture and rates of movement. Inclinometer data revealed the presence of the rupture surface at a depth of about 20m. DGPS monitoring allowed rates of movement up to several tens of centimetres per year to be recorded. The nearby village of Civitanova del Sannio can still be considered at risk due to the landslide, as recent remedial works, consisting mainly of very shallow re-shaping of the slope by blasting and partial filling of trenches, did not succeed in stopping its movement