Summary:

The paper is an attempt to determine the suitability of unmanned aerial vehicles (UAV) for geomorphological studies. The research was carried out in the Tatra National Park (green trail from Myślenickie Turnie to Kasprowy Wierch). Morphogenetic processes occur with high intensity in this area and give rise to numerous erosive form. A multirotor equipped with a non-metric visible light camera was used for measurements. The acquired data was used to generate a high resolution orthophotomap and a digital surface model (DSM). As part of the in-field data capture, geomorphological mapping of the research area was carried out as well. On this basis, it was possible to assess the suitability of the generated DSM for the geomorphological research. Moreover, the correlation between the DSM and the terrestrial geomorphological mapping is evaluated. In virtue of obtained data, effects and the intensity of tourist trails erosion were assessed in this part of the Tatra Mountains. The analysis involved the orthophotomap and the DSM (current data) as well as archival data from aerial laser scanning (ALS) conducted in 2012. Interpretation of above-mentioned results allowed to conclude that the data originating from UAV is very helpful in geomorphological studies. It is possible to determine the level of trails erosion and their spatial changes with high accuracy. Furthermore it allows to assess visually and quantitatively the extend of the land transformations (e.g. determine the volume of removed rock waste and soil). In conclusion, it is also possible to prescribe the further course of erosion processes and identify areas that might be suffered by erosion in the near future. This in turn will allow to change trails planning strategy, in order to minimize the impact of anthropogenic effect caused by intensified tourist flows.