In: Catena, 2008, vol. 72, no. 2, p. 248-258
Due to the effect of global change, the potential risk of natural hazards occurring in alpine areas is expected to increase to an even higher risk-level than has been recorded during the last century. These global changes potentially also have distinct influences on fluvial processes in torrents causing erosion on slopes and riverbanks in forested areas. Dating the time of root exposure along...
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In: Geomorphology, 2007, vol. 87, no. 4, p. 337-351
Debris flows are a major threat in many parts of the Alps, where they repeatedly cause severe damage to infrastructure and transportation corridors or even loss of life. Nonetheless, the spatial behavior of past debris-flow activity and the analysis of areas affected during particular events have been widely neglected in reconstructions so far. It was therefore the purpose of this study to...
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In: Catena, 2008, vol. 72, no. 1, p. 67-78
Dendrogeomorphological analyses of trees affected by debris flows have regularly been used to date past events. However, this method has always been limited to forested cones where trees registered the impact of previous events. The minimum age dating of trees growing in the debris deposits can, in contrast, provide information on the latest possible moment of past activity. In this paper, we...
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In: Natural Hazards, 2006, vol. 39, no. 1, p. 51-70
Over the last few years, rockfall research has increasingly focused on hazard assessment and risk analysis. Input data on past rockfall activity were gathered from historical archives and lichenometric studies or were obtained through frequency– volume statistics. However, historical records are generally scarce, and lichenometry may only yield data with relatively low resolutions. On...
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In: Earth Surface Processes and Landforms, 2006, vol. 31, no. 11, p. 1424 - 1437
Dendrogeomorphology was used to investigate past events on a cone affected by both debris flows and snow avalanches. We report on results of 520 cores from 251 injured Larix decidua Mill. and Picea abies (L.) Karst. trees sampled on the Birchbach cone (Swiss Alps). Detailed analysis of tree-ring sequences allowed dating of 561 growth disturbances in individual trees for a 252 yr...
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In: Geomorphology, 2006, vol. 74(1-4), p. 219-231
Rockfall is a major threat to settlements and transportation routes in large parts of the Alps. While protective forest stands in many locations undoubtedly reduce rockfall risk, little is known about the exact frequency and spatial distribution of rockfall activity in a given place or about how these parameters can be assessed. Therefore, the objective of the present study was to reconstruct...
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In: Forest Ecology and Management, 2006, vol. 225, p. 1-3
We used one of the few rockfall models explicitly taking trees into account and compared the results obtained with the 3D simulation model RockyFor with empirical data on tree impacts at three mountain forests in Switzerland. Even though we used model input data with different resolutions at the study sites, RockyFor accurately predicted the spatial distribution of trajectory frequencies at all...
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In: Arctic Antarctic and Alpine Research, 2005, vol. 37(3), p. 387-395
Three major rainfall events have caused considerable damage in the Valais region (Swiss Alps) since 1987. While important debris flows originating from periglacial environments were recorded during the August 1987 and September 1993 rainfall events, no debris flows occurred in October 2000. This paper aims at putting these large area events and the apparent increase in debris flow frequency into...
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In: Zeitschrift für Geomorphologie, 2005, vol. 49, no. 1, p. 89-106
Mit Hilfe dendrochronologischer Methoden wurde auf einem bewaldeten Hang im Täschgufer, Täsch (Schweizer Alpen) die Steinschlagaktivität während der letzten 25 Jahre untersucht. Um die saisonale Verteilung des Steinschlags zu bestimmen, wurde ein neuer Ansatz gewählt, welcher das Einsetzen von Kallusgewebe und Harzkanälen im geschädigten Holz untersucht. Die Ergebnisse von 270...
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In: Geomorphology, 2005, vol. 68(3-4), p. 224
For the first time, dendrogeomorphology has been used to investigate spatial and temporal variations of rockfall activity in a protection forest. We report results of 564 cores from 135 severely injured Larix decidua Mill. trees on the west-facing Täschgufer slope, Swiss Alps. While trees sampled reached an age of 297 years on average, the oldest one attained breast height in AD 1318. For...
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