Use of 3d process-based model to determine forests protecting against rockfall – case study Kamniška Bistrica

Abstract

This case study of the Kamniška Bistrica forest management unit presents a 3D process-based model for determining forests protecting against rockfall. Modelling was performed using the ArcGIS 9.3.1 tool; the kinetic energy of rockfalls was calculated using the Conefall friction model. The finished map of protective forests was compared with the map of protective functions of forests, made by the Slovenia Forest Service. The protective function map covers 90% of forests classified in the 1st category forests by the modelled map. Taking into consideration the entire forest area in the forest management unit, the maps match in 48% of cases. The differences appear predominantly in higher altitudes where the protective function map includes dwarf pine sites, and in lower altitudes where the map does not consider the possibility that trees can perform their protective functions where the terrain becomes level. The aim of this article is to draw attention to the possibilities of using the models as tools for determining forests protecting against rockfalls.