The road that leads to Ljubelj tunnel is threatened by numerous rock sources that lie above. A detailed delineation and description of terrain characteristics polygons and forest stands were performed. 61 sample plots were set up, on which all living trees with DBH above 1,27 cm were measured. Observed share of beech in growing stock was 71 %, spruce 22 % and sycamore maple 3 %. Frequency distribution of tree species by diameter class indicated negative exponential distribution. If only beech trees were considered the distribution changed to bell shaped, which is undesired regarding long-term protection function. Cutting of older beech trees and with that promotion of regeneration is recommended. Areas of rock fall hazard were determined using computer programs Rockyfor3D, Rockfor.NET and method of shadow angle (functionViewshed in ArcMap program). Assessment was done of how the endangerment of the road changes if different scenarios are used (forest without cable crane lines, forest with present cable crane lines, forest with cable crane lines positioned diagonal to the slope direction and gape type cutting, forest with cable crane lines that follow the slope direction and plenter forest). Results showed that there are no significant differences between different scenarios with forest, but there are differences in size of endangered areas depending on the used method. Analysis with program Rockyfor3D considered more factors and was more difficult, but gave us more trust worthy results.
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