Abstract ID: 3.9135 | Accepted as Talk | Talk/Oral | TBA | TBA

In mountain areas, human settlements have benefited from the widespread forest cover on steep slopes, providing a natural means of protection against natural hazards. Although the importance of this forest ecosystem service is widely recognized, open questions remain regarding its long-term and reliable provision, which will amplify with climate change. In particular, natural disturbances, such as windstorms, can cause temporary losses of the forest’s protective effect, potentially leading to higher natural hazard risks. In this study, we analyzed the recovery of the protective effect of a large number of windthrow areas in the Swiss Alps 13 and 31 years after storm Vivian using high-resolution canopy height models and single tree detection. We observed a considerable recovery of tree height (67 % on average), forest cover (90 %) and stem density (46 %) 31 years after the storm. Basal area showed a lower recovery of 16 % on average with 25 % of the studied areas showing a retarded recovery of ≤ 6 %. This highlights the extended timescales required for full recovery of the protective effect against certain hazard types, such as rockfall or landslides. Recovery rates were most importantly influenced by temperature, precipitation, local topography, gap size and lithological substrate, underlining the importance of local environmental conditions when predicting recovery.