Alessandro Trigila

Landslide Susceptibility Mapping at National Scale: The Italian Case Study

Landslide susceptibility maps are key tools for land use planning, management and risk mitigation. The Landslide susceptibility map of Italy, scale 1:1,000,000 is being realized by using the Italian Landslide Inventory – Progetto IFFI and a set of contributing factors, such as surface parameters derived from 20 to20 m DEM, lithological map obtained from the geological map of Italy 1:500,000, and land use map (Corine Land Cover 2000). These databases have been subjected to a quality analysis with the aim of assessing the completeness, homogeneity and reliability of data, and identifying representative areas which may be used as training and test areas for the implementation of landslide susceptibility models. In order to implement the models, physiographic domains of homogeneous geology and geomorphology have been identified, and landslides have been divided into three main classes in order to take into account specific sets of conditioning factors: (a) rockfalls and rock-avalanches; (b) slow mass movements, (c) debris flows. The modelling tests performed with different techniques (Discriminant Anaysis, Logistic Regression, Bayesian Tree Random Forest) provided good results, once applied with the appropriate selection of training and validations sets and with a significant number of statistical units.

Landslide Impacts in Europe: Weaknesses and Strengths of Databases Available at European and National Scale

Landslides represent a major threat to human life, property, buildings, infrastructure and natural environments in most mountainous and hilly regions of the world. The purpose of this work is to present the results of the analysis carried out by ISPRA on main landslide events and available databases in Europe. The major landslide phenomena occurred in Europe have been collected from the analysis of global disaster databases. For the period 2003–2010, 112 major landslides were recorded. These events, which often occurred at multiple sites for the same triggering factor, claimed a total of 152 fatalities and damaged or destroyed several buildings and transportation infrastructure.

Cultural Heritage, Landslide Risk and Remote Sensing in Italy

Italy is the country that owns most of the world cultural heritage and is affected by a very large number of landslides widespread throughout its territory. Aim of the work is to define a methodology, developed on GIS platform, in order to assess cultural heritage exposed to very slow and extremely slow mass movements using: SAR data, the Italian Cultural Heritage database and the Italian Landslide Inventory. The methodology has been developed at provincial level and tested on Macerata province. A single building approach has been also performed on six cultural heritage. The proposed methodology could be applied to all cultural heritage sites in Italy to identify priorities and plan field surveys, detailed studies and monitoring systems.

Population Exposed to Landslide and Flood Risk in Italy

Italy is one of the European countries most affected by landslides and floods. It counts over 499,000 mass movements with a total area of 21,200 and 23,903 km2 of flood hazard zones. Moreover it is a densely urbanized country with about 200 inhabitants per sq. km. The aim of this work is to estimate the population exposed to landslide and flood risk in Italy, on the basis of the Italian Landslide Inventory, the flood hazard zones, the Italian Population Census data, the high-resolution (HR) Artificial surfaces-Imperviousness Layer (Geoland2) and the Urban Atlas land use data. Two methods of estimation have been implemented at national scale: the former, assuming the resident population uniformly distributed within each census tract; the latter, using the HR Imperviousness Layer in order to spatialize the population within urban settlements of each census tract. The analysis estimates that almost 1 million persons are exposed to landslide risk and over 6 millions to flood risk.

Integration of Geohazards into Urban and Land-Use Planning. Towards a Landslide Directive. The EuroGeoSurveys Questionnaire

Exposure to hazards is expected to increase in Europe, due to rapid population growth in urban areas and the escalation of urbanization throughout many countries. In the framework of the European Geological Surveys (EGS), the Earth Observation and Geohazards Expert Group (EOEG) has carried out a survey based enquiry regarding the integration of geohazards (earthquakes, volcanoes, landslides, ground subsidence, floods and others) into urban and land-use planning. Responses from 19 European countries and 5 regions reveal heterogeneous policies across national borders. 17% of the countries have not yet implemented any legal measures to integrate geohazards into urban and land-use plans and half of the participating countries have no official methodological guides to construct geohazard maps. Additionally, there is a scarce knowledge about real social impacts of geohazards and resulting disasters in many of the countries, although they have a significant impact on their national economies. This overview stresses the need for a common legislative framework and homogenization of the national legislations as well as mutual guidelines which adopt the principles applicable to the management of geohazards and explain the process to be followed in the production of hazard documentation. This is especially relevant in case of landslide and subsidence hazards; although those are of great importance in Europe, there are no common guidelines and practices similar to Directive 2007/60/EC on the assessment and management of flood risk. Based on their expertise, EuroGeoSurveys (EGS) have the potential to coordinate this activity in European geohazard guidelines and to promote the interaction among stakeholders.

Landslide Risk Assessment and Management Using IT Services and Tools: The EU BRISEIDE Project Approach

The increasing damage caused by natural hazards in the last decades in Europe, amplified by recent events including landslides (Messina, Sicily, September 2009), earthquakes (L’Aquila, Abruzzo, April 2009), forest fires (Greece, 2008) and floods (Central Europe) in the last years, points out the need for interoperable added-value services to support environmental safety and human protection. Many environmental analyses, e.g. monitoring seismic sequences, early warning systems for the evolution of intense rainstorms, the path of forest fires, cannot be performed without considering the evolution, over time, of geographic features. For this reason, providing access to harmonized data is only one of several steps towards delivering adequate support to risk assessment reduction and management. Scope of the present work is to present the implemented risk reduction and management pilots developed by BRISEIDE’s team project.