Unravelling the recent dynamics of headwaters based on a combined dendrogeomorphic approach (a case study from the Sudetes Mts., Czech Republic)

ABSTRACT

Headwater catchments are frequently prone to debris flows/floods. Dendrogeomorphic methods allow for the accurate dating of the frequencies and spatial patterns of these events. Nevertheless, a combined approach based on the sampling of increment cores from tree stems and the extraction of cross-sections of scarred roots has been rarely used together at one site to determine the headwater dynamics. Such sampling strategy was performed in the Rudohorský potok catchment (the Hrubý Jeseník Mountains, Eastern Sudetes, Czech Republic) to compile the debris flow/flood chronology and to describe the detailed spatial patterns in the studied sub-catchments. In total, 44 events of increased hydrogeomorphic activity during the last 110 years were identified based on the analysis of 860 growth disturbances from 322 trees and 85 roots. The largest events (debris flows) occurred in 1921, 1951, 1965, 1975, 1991, 1997, 2001 and 2010. Higher dynamics of hydrogeomorphic processes were investigated in the sub-catchment affected by deep-seated rockslides. The inclusion of root analyses facilitated the completion of the event chronology mainly during the last 20 years. With respect to the decreasing sensitivity of tree stems with increasing age to the recording of geomorphic disturbances, the root analysis helped to better illustrate the spatial imprint of recent debris flow events (especially the most recent one in 2010).

KEYWORDS:

• Dendrogeomorphology
• headwaters
• debris flow
• Eastern Sudetes
• Czech Republic

Acknowledgements

Dr. Pavel Roštínský and Prof. Tomáš Pánek are warmly acknowledged for providing their findings from field mapping. English language was improved by American Journal Experts.

Disclosure statement

No potential conflict of interest was reported by the author.

Data availability statement

The author confirms that the data supporting the findings of this study are available within the article.

Notes on contributor

Radek Tichavský received his PhD in Environmental Geography at the University of Ostrava, Czech Republic. His specialization is dendrogeomorphology with focus on the spatio-temporal reconstructions of various natural processes (mainly debris flows, floods, rockfalls, and landslides) and identification their climate triggers. His work is primarily oriented in the most dynamics parts of the Central European mid-mountain regions.

ORCID

Radek Tichavský http://orcid.org/0000-0002-8187-5313

Additional information

Funding

This work was supported by the project of the University of Ostrava under the number SGS05/PřF/2017–2018: Development and contemporary state of landscape understanding in the Western Carpathians and east-sudetic mountains in context of man impact and recent natural hazard.