Streszczenie:

Erosion is a natural phenomenon which constantly changes the shape of the Earth's surface, yet it is regarded as a very serious harmful factor by people in view of their economic and investments activities. Ski slopes are a special example of areas with a serious erosion hazard due to a permanent deforestation, considerable longitudinal slopes, engineering works, levelling ski slopes, but also because of abundant surface runoff. The aim of the research was to compare the extent of potential soil erosion in deforested areas intended for ski slopes, with various anti-erosion measures implemented, as well as to discuss the possibility of RUSLE erosion model application under these conditions.
The researched objects were ski runs on the eastern slopes of Mount Jaworzyna Krynicka (The Beskid Sądecki Mts.). Potential erosion was computed in the areas of seven ski slope segments in four variants of the area cover and applied anti-erosion measures. Some computational data (the ski slope area, average slope gradients, soil granulometric composition) were obtained from the Forest Digital Map and Digital Terrain Model, whereas numerical indicators used for the model were established on the basis of the subject literature.
Under presented conditions, potential erosion losses were greatly diversified. The biggest losses, expressed as erosion losses factor A, have been indicated for variant I (naked soil, without anti-erosion measures) and varied from ca. 18 to ca. 36 Mg·ha-1·year-1. Sodding ski slopes diminished potential erosion to 4.5% of the value obtained for the comparative variant (variant I), while shortening of the surface runoff length without sodding may reduce potential erosion losses to ca. 20÷25%. Combination of both measures may significantly reduce the erosion in these areas (to ca. 0.04%). The obtained results are analogous to other authors' findings.