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Tree uprooting plays an important role in hillslope evolution. The geomorphological impact of tree uprooting after a foehn wind occurrence, in December 2013 in the Tatra Mountains, was investigated. Geomorphological mapping was conducted in three watersheds. Additionally, in one of the watersheds, 459 windthrow pits were measured, in an area of 6.4 ha. The mean volume of a pit was 2.41 m 3 , and the mean surface area was 5.47 m 2 . 3.9% of the area was affected by windthrow pits, however locally the magnitude of changes was significantly higher, reaching up to 14.5% of the surface area. Slope inclination weakly influenced the effects of uprooting, and a decrease in the average depth of pits on steep slopes was observed. Individual windthrow pits (five cases) initiated the activity of geomorphological processes, and two cases of periodic springs were noted. Changes in the relief of small landforms caused by tree uprooting were documented. Windthrow creation facilitated the delivery of the soil material from the slopes into the channels.

The main aim of this research was to determine the magnitude of geomorphologic changes within a section of a forest road. The research was carried out in the Lejowa Valley in the Tatra Mountains. The measurements of the surface of the road were performed using a RIEGL VZ-4000 terrestrial laser scanner (TLS). TLS models for 2017, 2018, and 2019 served as the basis for the determination of quantitative and spatial relief transformations. The net annual change on the studied road within the first period equaled −884 m3 ha−1 year−1, and for the second period −370 m3 ha−1 year−1. Changes across the accumulation fan ranged from −265 m3 ha−1 year−1 to +36 m3 ha−1 year−1. The average rate of erosion on the studied abandoned road is similar, and sometimes even greater than that on roads which are still in use. Our research shows that improper road location may lead to irreversible changes to the natural environment. The planning of a forest road must take into account natural conditions, otherwise progressive relief transformations may lead to significant surface changes and the road may be excluded from use.

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The main aim of this paper was to determine the rate of erosion and aggradation within a forest road on different geological structures as well as a comparison of changes between roadbeds and road cutslopes. The research was conducted in the Lejowa Valley in the Tatra Mountains. The measurements of the forest road were performed using a Leica ScanStation C10 terrestrial laser scanner (TLS) with a set of six-inch Leica High Definition Survey (HDS) targets. Based on the multi-temporal digital elevation models (DEMs) two DEM of Differences (DoD) were created for the summer season of 2019 and the 2019-2020 period. The research has shown that there is a significant difference between the rate of relief change for roads constructed atop conglomerates and limestone. The net change for the road within conglomerates was an erosion of 432.37 m 3 ha -1 yr -1 , while for the road within limestone it was a sediment deposition which amounted to 3.87 m 3 ha -1 yr -1 . Research has shown that there exists a difference in the rate of erosion for road cutslopes and roadbeds constructed within conglomerates. It was shown that the erosion rate for the roadbeds was 1.7-times larger than that for the studied road cutslopes in the period 2019-2020. Improperly designed and constructed forest roads may be subject to intensive relief transformations, even after they are no longer in use.