Riccardo Fanti

Bio: Riccardo Fanti is an academic researcher from University of Florence. The author has contributed to research in topics: Landslide & Debris flow. The author has an hindex of 24, co-authored 67 publications receiving 2228 citations.

Rainfall thresholds for the forecasting of landslide occurrence at regional scale

Abstract: This paper concerns a regional scale warning system for landslides that relies on a decisional algorithm based on the comparison between rainfall recordings and statistically defined thresholds. The latter were based on the total amount of rainfall, which was cumulated considering different time intervals: 1-, 2- and 3-day cumulates took into account the critical rainfall influencing shallow movements, whilst a variable time interval cumulate (up to 240 days) was used to consider the triggering of deep-seated landslides in low permeability terrains. A prototypal version of the model was initially set up to define statistical thresholds. Then, thresholds were calibrated using a database of past georegistered and dated landslides. A validation procedure showed that the calibration highly improves the results and therefore the model was integrated in the regional warning system of Emilia Romagna (Italy) for civil protection purposes. The proposed methodology could be easily implemented in other similar regions and countries where a sufficiently organised meteorological network is present.

Landslide activity as a geoindicator in Italy: significance and new perspectives from remote sensing

Abstract: Landslide activity responds to rapid environmental changes and represents a relevant geoindicator in mountainous or hilly areas. This paper discusses the socio-economic relevance of landslide hazard in Italy and the problems encountered in establishing relationships between landslide frequency, climate and vegetation changes at different time scales. Landslides blocking a river channel have been carefully taken into account because they are usually characterized by high intensities (with regard to the involved masses and movement velocities) and their occurrences are often datable via radiocarbon dating. This is due to the recovery of organic matter in the landslide dammed lakes. For these reasons they can be considered important geoindicators in the wider category of slope failures. The marked effects of the anthropogenic activity on slope instability processes in the last 50 years are discussed with reference to two case histories: the Chianti hills in Tuscany and the Cinque Terre National Park in Liguria. Finally, two novel techniques of remote sensing are proposed as tools for a systematic monitoring of slope instability at different time and spatial scales. Both techniques are based on the interferometric synthetic aperture radar (SAR) technology and differ on the type of platform (satellite and ground-based) used to acquire data.

Ground Motion Characteristics Estimated from Spectral Ratio between Horizontal and Verticcl Components of Mietremors.

Abstract: The spectral ratio between horizontal and vertical components (H/V ratio) of microtremors measured at the ground surface has been used to estimate fundamental periods and amplification factors of a site, although this technique lacks theoretical background. The aim of this article is to formulate the H/V technique in terms of the characteristics of Rayleigh and Love waves, and to contribute to improve the technique. The improvement includes use of not only peaks but also troughs in the H/V ratio for reliable estimation of the period and use of a newly proposed smoothing function for better estimation of the amplification factor. The formulation leads to a simple formula for the amplification factor expressed with the H/V ratio. With microtremor data measured at 546 junior high schools in 23 wards of Tokyo, the improved technique is applied to mapping site periods and amplification factors in the area.

Use of LIDAR in landslide investigations: a review

Abstract: This paper presents a short history of the appraisal of laser scanner technologies in geosciences used for imaging relief by high-resolution digital elevation models (HRDEMs) or 3D models. A general overview of light detection and ranging (LIDAR) techniques applied to landslides is given, followed by a review of different applications of LIDAR for landslide, rockfall and debris-flow. These applications are classified as: (1) Detection and characterization of mass movements; (2) Hazard assessment and susceptibility mapping; (3) Modelling; (4) Monitoring. This review emphasizes how LIDAR-derived HRDEMs can be used to investigate any type of landslides. It is clear that such HRDEMs are not yet a common tool for landslides investigations, but this technique has opened new domains of applications that still have to be developed.