Spatial distribution and controlling factors of snow avalanche and debris flow in Parâng Mountains

The alpine slopes of Parâng Mts. are prone to snow avalanche (SA) and debris flow (DF) activity due to favorable lithological, topo-climatic and vegetation cover conditions. Since tourism activities are continuously increasing, tourists and related infrastructure in this area might be exposed to different levels of risk. Our study is a preliminary research that aims to analyze the spatial distribution and controlling factors of SA and DF processes in Parâng Mts., which represent natural hazards threating the areas destined for tourism activities and associated infrastructure. First, the spatial distribution pattern of SA paths and DF tracks was identified and mapped on orthophotoplans, then checked in the field and integrated in a database for analysis. Subsequently, a set of instability factors influencing directly the spatial distribution of SA and DF activity were analyzed. The following instability factors were taken into consideration and statistically analyzed using ArcGIS software: slope, altitude, aspect, planar and profile curvature (automatically extracted from 10 m resolution DEM), vegetation cover (mapped on orthophotoplans) and lithology (extracted from the geological maps at 1:200.000 scale). Information regarding the spatial distribution of tourist frequented areas and the related infrastructure (hiking trails, chalets, ski lifts, ski pistes etc.) were analyzed in conjunction with the spatial distribution of geomorphic process activity. In areas with tourism activities, future research will focus on mapping terrain susceptibility to SA and DF processes. Moreover, dendrogeomorphic reconstructions will allow to determine the occurrence probability of SA and DF activity, which will serve to finally get an accurate geomorphic hazard zonation within the study area. Keywords— spatial distribution; controlling factors; snow avalanche; debris flow; Parâng Mountains; ZonaGeoTour