Landslide evidence and spatial prediction - Application of data and information from landslide maps

Landslide maps produced by LiDAR (Light Detection and Ranging) are very clear and detailed representation of the phenomena and in many cases reveal evidence of past landslides that are virtually invisible by other detection techniques due to vegetation cover. Over the last decade, airborne laser scanning (ALS) has been made available and has been used to identify and map landslide. LiDAR elevation data prove particularly effective for mapping of small and shallow landslides in areas that are partially or completely covered by dense vegetation that are difficult or impossible to identify using conventional identification techniques. The first topic covered in the talk is landslide detection and mapping using very high-resolution LiDAR DTM to obtain complete historical inventories of shallow soil slides. Few examples of landslide inventory maps from different geomorphological environment of the Republic of Croatia will be presented to show typical landslide distribution. For landslide spatial prediction, the talk focuses on the results of landslide susceptibility modelling and zonation performed for a range of coverages, starting with the largest encompassing whole territory of Croatia. Landslide susceptibility zonation was also performed for areas of two counties (Primorsko-Goranska County and Karlovac County) and few smaller pilot areas of cities and municipalities in the Pannonian Basin and in External Dinarides. The main objective of presented susceptibility zoning in different scales (national, regional and local scale) is to enable analysis of usefulness and reliability of map information (i.e., spatial distributions and rating of the terrain units according to their landslide propensity) for application in physical and urban planning. The needs of the decision-makers, planners and other stakeholders involved in landslide risk prevention are analyzed through the series of round-table discussions organized in Croatia in the framework of the project of applied research PRI- MJER (KK.05.1.1.02.0020). The ultimate goal is to create maps depicting information about landslides tailored according to needs of the system of physical planning in Croatia (particularly land use planning), encompassing local and regional level, harmonized at the national level. The research of the mapping methodologies is part of the project “Methodology development for landslide susceptibility assessment for land-use planning based on LiDAR technology, LandSlidePlan” (HRZZ IP-2019-04-9900) fully supported by Croatian Science Foundation.