This master thesis presents the role of high gradients (slopes) in torrential streams. Results of previous researches by different authors are collected, followed by the descriptions of the characteristics of typical geomorphologic forms of channels in torrential areas. Functions of instream wood, erosion, transport and accumulation of sediment , hydropower potential, and stream power as parameter for energy dissipation in stream are also shown.
The thesis discusses thirty-four torrential streams on the slopes of Karavanke in the Upper Sava Valley, Eastern Alps. Field examination of individual, more eccessible reaches has been made. The method for analysis of longitudinal profiles of streams and basins with ArcGIS software tools is described. The usability of DEM 12.5, DEM 5 and LiDAR DEM with spatial resolution 0.5 and 1 meter is compared. From the results obtained from LiDAR DEM, the possibility of identifying the geomorphologic forms in streams and the periodic changing of local slopes on shorter sections is discussed. Whole longitudinal profiles are produced and their future erosion activity estimated. A few variations of normalised values of vertical drops and torrent lengths are made. The threshold of the envelope is determined for the obtained results. Finally, stream power and its changes along the stream are also analysed by examining four torrents.
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