A predictive model for susceptibility to European spruce bark beetle (ips typographus) attacks: a case study of eastern South Tyrol

The thesis focusses on the European spruce bark beetle (Ips typographus) epidemics, phenomenon that is affecting and damaging several mountain forests of the northern hemisphere. The spread of these outbreaks has become a major concern in recent years, demanding effective management strategies. The study aims to predict the likelihood of bark beetle attacks by applying geostatistical analysis to several variables in the eastern South Tyrol region. More specifically, it examines the impact of the heavy snowfalls that affected the area of interest in 2019 and 2020, as well as the probability of attack in relation to topography, climate, forest structure (tree height), distance from previous infestations, tree species diversity, drought, and vegetation development. The data were collected from various platforms and subsequently standardized to rasters with a spatial resolution of 30 x 30 m, as well as standardized in terms of extent, and reference system using the R software. The logistic regression model utilized for the geostatistical analyses was also created and implemented using the R software. The conducted study confirms that the likelihood of bark beetle attacks increases in warm and dry climate. It also proves that future Ips typographus attacks are more likely to occur in previously infested areas. These findings can be fundamental for the implementation of future proactive management strategies and interventions in regions at higher risk of attack. However, this work is quite limited in terms of geographical extent and including data from the year 2023 could be important for validating the results and conducting further examinations. Thus, additional research is needed to confirm the robustness of the applied model and to generalize the outcomes of the analyses. Nonetheless, the created model could serve as a good starting point for further studies and validates geostatistics as a useful tool for analysing European spruce bark beetle epidemics.