Schmidt M.,The Northwest German Forest Research Station NW FVA |
Hanewinkel M.,Forest Research Institute of Baden Wurttemberg FVA Baden Wurttemberg |
Kandler G.,Forest Research Institute of Baden Wurttemberg FVA Baden Wurttemberg |
Kublin E.,Forest Research Institute of Baden Wurttemberg FVA Baden Wurttemberg |
Kohnle U.,Forest Research Institute of Baden Wurttemberg FVA Baden Wurttemberg
Canadian Journal of Forest Research | Year: 2010
Based on individual tree damage data dating back to the gale "Lothar" (winter 1999) in Baden-Württemberg, Germany, a statistical model was developed to estimate the risk of storm damage for individual trees. The data were compiled from the National German Forest Inventory. The model attempts to separate the effects of tree-specific variables, topography, site conditions and flow field related effects on damage probability. The crucial problem of missing information on the actual flow field parameters was solved by applying a generalized additive model that enables the simultaneous fit of a spatial trend function. The geographical location of risk hotspots as predicted by the model correspond well to the actual distribution pattern of storm damage as assessed by the forest service. Tree height proved to be one of the most important factors affecting the level of damage, while height to diameter at breast height ratio influences damage probability to a much lesser extent. The Norway spruce (Picea abies (L.) Karst.) group has the highest potential to be damaged followed by the silver fir (Abies alba Miller) - Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) group and the Scots pine (Pinus sylvestris L.) - larches (Larix spp.) group. Predicted probabilities for deciduous trees are generally lower than those of conifers. West- to south-exposed locations bear a considerably higher damage risk and waterlogged soils show an increased predicted probability compared with slightly or not waterlogged soils.