IJEGE Special Issue 2011 - Selected papers by FIST "GEOITALIA 2009" Congress - Presentation

This special volume of the IJEGE gathers a selection of papers focused on fluvial dynamics and geological-hydraulic risks. The papers were presented in some sessions of the FIST “GEOITALIA 2009” congress, which was held in Rimini in September 2009. The following are the titles of the sessions, together with the names of their Conveners: - Fluvial morphodynamics and interference with fast slope processes (Corrado Cencetti, University of Perugia - Piero Farabollini, University of Camerino); - Combined effects of extreme events: floods and landslides (Francesco Sdao and Aurelia Sole, University of Basilicata); - Monitoring, modelling and management of streambeds (Chiara Audisio, CNR-IRPI of Turin - Massimo Rinaldi, University of Florence - Nicola Surian, University of Padua). The topics covered by the papers reflect the broad range of issues connected with streambed dynamics. CAVALLI & TAROLLI introduce a methodological approach to the study of streams via innovative tools and techniques, such as LiDAR. On the same theme, TERUGGI, RINALDI, CHIAVERINI & OSTUNI deal with the contribution that terrestrial photogrammetry may give to the study of changes in and retreat processes of stream banks. The remaining papers address the geological-hydraulic risk conditions associated with streambed dynamics from different standpoints. PRESTA & DE LUCA tackle one of the crucial issues in natural risk management, i.e. adequate planning and implementation of risk communication activities, in general terms. CAPORALI, PILEGGI & FEDERICI refer to the flood which hit Versilia in 1996 to describe the process of design and development of a database, which integrates hydrological modelling of extreme events with historical data on floods, so as identify their hydraulic-meteorological causal factors. SDAO, SOLE, PASCALE & GIOSA analyse the “systemic vulnerability” of a complex urban area upon a combined landslide-flood event. The Authors stress that their proposed methodology is different from conventional ones (based on physical approaches), in that it considers the relations existing between the intensity of extreme events and their direct and indirect consequences on land, communities and built heritage. In particular, use is made of “pressure indicators” to qualitatively and quantitatively define the impact of various factors (not only physical, but also social and economic) on land. SOLE, GIOSA, CANTISANI, STATUTO & NOLÈ propose a sensitivity analysis for flood modelling in flat areas. The analysis is based on hydrodynamic simulations with 2D mathematical models, which take into account both the level of detail reached in the mapping of the study area and the resistance to motion of flood-prone alluvial plains. CASTORANI, DI SANTO, FRATINO, LIMONGELLI, MEZZINA, PAGANO, RAFFAELE & TRULLI present a methodological approach, called analysis of multihazards, i.e. the seismic and hydraulic hazards to which buildings, structures and infrastructures (e.g. bridges and viaducts) are exposed and which interfere with streambed dynamics. They propose various indicators to assess the vulnerability of buildings, structures and infrastructures to the above catastrophic events and to set priorities of action. CENCETTI, DE ROSA & MINELLI discuss the problem of landslide dams and, more generally, of the interference between streambed dynamics and landslide-prone slopes. They propose a sensitivity analysis of the main triggering factors of streambed damming by landslides. On the same theme and by reviewing a case study (Le Mottacce landslide on the Arno river), CENCETTI, DE ROSA & FREDDUZZI put forward a quantitative approach to the phenomenon, i.e. a cellular automation model (CAESAR). They demonstrate that, by changing the software code to account for the effect of large masses of material detached from slopes and invading a given stream (landslide dam), the model can be applied to the simulation of different short- and long-term scenarios, thereby assessing the evolutionary trend of the stream affected by this complex phenomenon. I am indebted to Alberto Prestininzi, Chief Editor, and to all the members of the editorial staff of the Journal for publishing these papers, which emphasise the Italian researchers’ keen interest in methodological approaches to the study of fluvial dynamics and associated geological-hydraulic risk conditions.