<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">Dendrochronological methods were used to determine the frequency of debris flow/avalanche events in a forest zone. A debris flow and avalanche track located in the Eastern Sudetes Mountains (Central Europe) was analysed. The length of the youngest debris flow/avalanche track is about 750 m. Three distinct sections of the debris flow can be identified along the longitudinal section: niche, gully and tongue. The dendrochronological study shows that trees started growing on the margins of the debris flow between 1908 and 1963. Hence, debris flow and/or avalanche events occurred on this slope at the turn of the 19th and 20th centuries. All trees collected from the tongue started growing between 1935 and 1964. However, a large debris flow event took place several years before, most probably during an extraordinary rainfall in June 1921. Following this event, several relatively large debris flows have occurred during the growing season, the strongest dendrochronologically confirmed events occurring in 1968, 1971-1972, 1991, 1997 and probably in 1977. Spring debris flow events induced by snow melt and/or avalanches have occurred in 1994 and 2004. The results suggest that with favourable geological conditions, debris flows can occur very frequently within entirely forested slopes.</abstract>

Dendrochronological methods were used to determine the frequency of debris flow/avalanche events in a forest zone. A debris flow and avalanche track located in the Eastern Sudetes Mountains (Central Europe) was analysed. The length of the youngest debris flow/avalanche track is about 750 m. Three distinct sections of the debris flow can be identified along the longitudinal section: niche, gully and tongue. The dendrochronological study shows that trees started growing on the margins of the debris flow between 1908 and 1963. Hence, debris flow and/or avalanche events occurred on this slope at the turn of the 19th and 20th centuries. All trees collected from the tongue started growing between 1935 and 1964. However, a large debris flow event took place several years before, most probably during an extraordinary rainfall in June 1921. Following this event, several relatively large debris flows have occurred during the growing season, the strongest dendrochronologically confirmed events occurring in 1968, 1971-1972, 1991, 1997 and probably in 1977. Spring debris flow events induced by snow melt and/or avalanches have occurred in 1994 and 2004. The results suggest that with favourable geological conditions, debris flows can occur very frequently within entirely forested slopes.

Dendrochronological Records of Debris Flow and Avalanche Activity in a Mid-Mountain Forest Zone (Eastern Sudetes — Central Europe)

Faculty of Earth Sciences, University of Silesia, Będzińska 60, 41-200 Sosnowiec, Poland

Institute of Geography and Regional Development, University of Wrocław, Pl. Uniwersytecki 1, 50-137 Wrocław, Poland

Geochronometria

Dendrochronological methods were used to determine the frequency of debris flow/avalanche events in a forest zone. A debris flow and avalanche track located in...

Dendrochronological Records of Debris Flow and Avalanche Activity in a Mid-Mountain Forest Zone (Eastern Sudetes — Central Europe)

Publié en ligne: 06 janv. 2010

Pages: 57 - 66

DOI: https://doi.org/10.2478/v10003-009-0011-7

Mots clés
debris flow, avalanche, dendrochronology, mid-mountains

This content is open access.

Dendrochronological Records of Debris Flow and Avalanche Activity in a Mid-Mountain Forest Zone (Eastern Sudetes — Central Europe)

Publié en ligne: 06 janv. 2010

Pages: 57 - 66

DOI: https://doi.org/10.2478/v10003-009-0011-7

Mots clésdebris flow, avalanche, dendrochronology, mid-mountains

This content is open access.

Mots clés
debris flow, avalanche, dendrochronology, mid-mountains