<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>High-gradient streams are localities with the most dynamic activity of geomorphological processes in medium-high mountains. This study of the frequency of floods and debris flows in a selected high-gradient stream in the Moravskoslezské Beskydy Mts was based on a dendrogeomorphic approach. It makes use of the most accurate methods applied in the dating of historic geomorphological processes. Individual events were reconstructed on the basis of the dating of various growth disturbances displayed in 99 samples taken from 56 predominantly broad-leaved trees.</p><p>As for the studied area, 26 years out of the last 113 years have been identified as years of rapid geomorphological processes. The frequency of the processes has been high above average since the 1970s. A majority of the events can be considered as flash floods. Debris flows, which can only be observed sporadically, originate due to the reactivation of old accumulation material that subsequently ends up re-accumulated on the alluvial fan at the mouth of a stream. A large number of events occur in connection with extreme short-term precipitation in summer months. In addition, they are affected by fast snow melting in spring, which has also been proved by intra-seasonal dating of selected events.</p></abstract>

High-gradient streams are localities with the most dynamic activity of geomorphological processes in medium-high mountains. This study of the frequency of floods and debris flows in a selected high-gradient stream in the Moravskoslezské Beskydy Mts was based on a dendrogeomorphic approach. It makes use of the most accurate methods applied in the dating of historic geomorphological processes. Individual events were reconstructed on the basis of the dating of various growth disturbances displayed in 99 samples taken from 56 predominantly broad-leaved trees.As for the studied area, 26 years out of the last 113 years have been identified as years of rapid geomorphological processes. The frequency of the processes has been high above average since the 1970s. A majority of the events can be considered as flash floods. Debris flows, which can only be observed sporadically, originate due to the reactivation of old accumulation material that subsequently ends up re-accumulated on the alluvial fan at the mouth of a stream. A large number of events occur in connection with extreme short-term precipitation in summer months. In addition, they are affected by fast snow melting in spring, which has also been proved by intra-seasonal dating of selected events.

Frequency of fast geomorphological processes in high-gradient streams: case study from the Moravskoslezské Beskydy Mts (Czech Republic) using dendrogeomorphic methods

Department of Physical Geography and Geoecology, University of Ostrava, Chittussiho 10, Ostrava - Slezská Ostrava, 710 00, Czechoslovakia

Geochronometria

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

High-gradient streams are localities with the most dynamic activity of geomorphological processes in medium-high mountains. This study of the frequency of...

Frequency of fast geomorphological processes in high-gradient streams: case study from the Moravskoslezské Beskydy Mts (Czech Republic) using dendrogeomorphic methods

Publié en ligne: 17 mars 2012

Pages: 122 - 132

DOI: https://doi.org/10.2478/s13386-012-0002-8

Mots clés
dendrogeomorphology, high-gradient stream, debris flow, flood, Moravskoslezské Beskydy Mts

© 2011 Silesian University of Technology, Gliwice, Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Frequency of fast geomorphological processes in high-gradient streams: case study from the Moravskoslezské Beskydy Mts (Czech Republic) using dendrogeomorphic methods

Publié en ligne: 17 mars 2012

Pages: 122 - 132

DOI: https://doi.org/10.2478/s13386-012-0002-8

Mots clésdendrogeomorphology, high-gradient stream, debris flow, flood, Moravskoslezské Beskydy Mts

© 2011 Silesian University of Technology, Gliwice, Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Mots clés
dendrogeomorphology, high-gradient stream, debris flow, flood, Moravskoslezské Beskydy Mts