Modelling bark beetle disturbances in a large scale forest scenario model to assess climate change impacts and evaluate adaptive management strategies

To study potential consequences of climate-induced changes in the biotic disturbance regime at regional to national scale we integrated a model of Ips typographus (L. Scol. Col.) damages into the large-scale forest scenario model EFISCEN. A two-stage multivariate statistical meta-model was used to upscale stand level damages by bark beetles as simulated in the hybrid forest patch model PICUS v1.41. Comparing EFISCEN simulations including the new bark beetle disturbance module against a 15-year damage time series for Austria showed good agreement at province level (RA(2) between 0.496 and 0.802). A scenario analysis of climate change impacts on bark beetle-induced damages in Austria's Norway spruce [Picea abies (L.) Karst.] forests resulted in a strong increase in damages (from 1.33 MmA(3)A a(-1), period 1990-2004, to 4.46 MmA(3)A a(-1), period 2095-2099). Studying two adaptive management strategies (species change) revealed a considerable time-lag between the start of adaptation measures and a decrease in simulated damages by bark beetles.