Hydro-meteorological monitoring activities in Portofino Natural Park (Italy) as demonstrator of the H2020 RECONECT project: preliminary results

The European Horizon RECONECT Project (Regenerating ECOsystems with Nature-based solutions for hydro-meteorological risk rEduCTion) aims to contribute to a European reference framework on NBS by demonstrating, upscaling and spreading large-scale NBS in rural and natural areas. The Italian RECONECT demonstrator is set in the Portofino Natural Park, which represents a unique natural landscape element with high ecologic, social, and economic (touristic) value and severely endangered by hydro-meteorological hazards. The Portofino Promontory is historically affected by geo-hydrological events. They can produce natural instability processes related to the interaction between meteorological phenomena and the geological environment, which can potentially cause loss of the exposed elements at risk, as happened in the past. The more frequent processes are: shallow landslides and flash floods, sea-storm surges, rockfalls and mud-debris flows. Often, different processes can occur simultaneously during an intense meteorological event, interacting each other and causing an avalanche effect. This research introduces the NBS interventions proposed in the RECONECT case study of Portofino over two pilot catchments (San Fruttuoso and Paraggi basins), visited by thousands of tourists all over the year. The project envisages the setting up of meteorological-hydrological stations for studying and monitoring geomorphological processes. In particular, RECONECT project foresees the selection, installation and operation of hydro-meteorological instruments that include three weather stations, two hydrometers and two cameras to monitor small and very steep catchments. Monitoring activity include the use of remote sensing survey LIDAR data, orthophotography and infrared aerial photography, whose acquisition has been carried out in January 2020. Remote sensing and monitoring data are used to quantitatively assess the morphological features and processes, allowing to: a) evaluate the critical-instability areas along the slope and channels and to support the reconstruction of dry stone walls of the widespread terraced areas; b) evaluate the potentially more susceptible source areas of mud-debris flows and the identification of thresholds in meteorological conditions. In relation to future projections of natural, social and economic impacts of climate change, NBS represent a relevant mitigation and adaptation strategy for the Portofino case study, which may be upscaled at national and international level.