Implementation of a prototype monitoring system to investigate post-fire geomorphic processes

The current abstract presents experimental analyses and monitoring to studying post-fire geomorphic processes, a potential indirect effect of wildfires. The primary goal is to identify environmental variables that could serve as indicators for triggering post-fire soil erosion and mass wasting in mountain watersheds.

Two pilot sites were chosen in southern Italy, and specifically in mountain regions severely affected by wildfires in the last years. The monitored environmental quantities include i) meteorological variables – precipitation, air temperature, wind speed and direction, lighting, barometric pressure and solar radiation – detected by modern all-in-one automatic weather station and a traditional tipping bucket rain gauge. ii) Soil moisture content and temperature measured by TDR sensors 10 cm-deep and Cosmic Ray Neutron Sensing. iii) Local seismicity measured by triaxial geophones. iv) Surface optical and thermal evolution using a combined RGB+thermal video camera.

Key research topics being tested include: 1) the application of image change detection techniques to analyze runoff, soil erosion, and landslides during post-fire rainstorms using visual and thermal imagery; 2) the use of a triaxial seismic sensor to capture ground vibrations and characterize sediment-laden turbulent flows; 3) spatial estimation of soil moisture conditions preceding post-fire geomorphic events; and 4) lightning detection to anticipate the approach of convective cells at the monitored sites. Alongside these positive aspects, the research team is addressing several challenges, such as managing remote control and communication, storing data locally, and ensuring reliable power supply.

Preliminary results obtained with the RGB+thermal images and seismic data, which have been acquired during a series of rainfall events that triggered soil erosion, small rock falls and hyperconcentrated flows suggest that the involved instrumentations can represent a valuable tool in monitoring mass wasting processes linked to intense precipitations after wildfires. Future testing and implementations should contribute to develop an innovative monitoring system to assist public authorities in managing post-fire risks.

This work was funded by the Next Generation EU - Italian NRRP, Mission 4, Component 2, Investment 1.5, call for the creation and strengthening of 'Innovation Ecosystems', building 'Territorial R&D Leaders' (Directorial Decree n. 2021/3277) - project Tech4You - Technologies for climate change adaptation and quality of life improvement, n. ECS0000009. This work reflects only the authors’ views and opinions, neither the Ministry for University and Research nor the European Commission can be considered responsible for them.