The aim of the master's thesis was to examine the spatial distribution, morphometric characteristics and surface changes of talus slopes in the central part of the Kamnik-Savinja Alps. Talus slopes were mapped and classified according to their morphology and sediment supply using orthophotos, LiDAR data and digital elevation models (DEM) produced photogrammetrically from aerial photographs. Their areas, elevations, elevation differences, mean slope angles and dominant aspects were determined. Surface changes were analysed using the DEM of Difference method (DoD) with a minimum level of detection for the periods 2011–2015, 2015–2017, 2017–2021 and 2021–2024. The periods of detected change were compared with intense rainfall events, while the interpretation of selected areas was verified through field surveys.
A total of 125 talus slopes, 8 torrential fans and 8 debris tongues were mapped in the study area. The mapped talus slopes cover 409.29 ha, representing approximately 6 % of the study area. Talus aprons are the dominant type of talus slopes, while larger and more continuous talus slopes mainly occur on the northern side of the mountain range. Northeast and north-facing aspects are the most common, and the mean slope angles of individual talus slopes range from 24.5° to 40.4°. Surface changes were detected in 62 of the 141 studied depositional landforms. The greatest extent of change was identified in the period 2021–2024, when larger erosion channels, fan-shaped and tongue-shaped deposits developed on several talus slopes. The temporal coincidence of these changes with the extreme rainfall event of 4 August 2023 suggests that the event may have contributed to sediment transport.
The combined use of multi-temporal spatial data and field validation enabled a reliable identification of larger areas of erosion and accumulation. The main limitations were snow, vegetation and multi-year intervals between surveys, which prevented the exact timing and cause of individual changes from always being determined.
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