Abstract ID: 3.12800 | Accepted as Talk | Requested as: Talk | TBA | TBA

Forest disturbance regimes are changing across Europe, increasingly impacting the services provided by these ecosystems. In the Alps, key services like protection are increasingly threatened by natural disturbances. Information on the distribution and impacts of recent disturbances on protection forests is needed to inform effective post-disturbance management interventions but is often not available at the required level of detail. Here, we chose the province of South Tyrol (Italian Alps), a mountainous region where forests were recently disturbed by wind, snow and bark beetle to: i) map recent disturbances in the region and analyze their spatial patterns and interactions, and ii) to quantify the loss of forest protective effects, including areas where protection is still provided by dead trees but will be lost in the near future.

We derived forest disturbance maps for the years 2019-2023 by analyzing Sentinel-2 time-series. Then, we used multi-source predictors including spectral and patch characteristics, and a supervised machine learning classifier to attribute disturbed areas to different agents (wind, snow, bark beetle). We assessed the correlations among disturbance agents and evaluated their impact on direct and indirect protection forests. Finally, we performed a pixel-based classification to map standing dead trees in disturbed areas providing residual protective effects.

Our results show that disturbances affected around 6% of forests in our study region, with wind and snow having similar impacts and bark beetle causing larger damages. Bark beetle-disturbed areas had a higher correlation with snow-damaged areas than with wind-damaged areas. Compared to the other disturbance agents, bark beetle affected protection forests the most. Around 22% of the disturbed protection forests are still providing a certain degree of protection due to standing dead trees.

We provide here the first detailed map of recent disturbances for the province of South Tyrol. Additionally, by identifying areas where the protective effect is entirely lost and areas at risk of losing their protective effects soon, our mapping products can be used as a practical tool to guide decision-makers in prioritizing management interventions to support post-disturbance mountain forest recovery.