In: Permafrost and Periglacial Processes, 2017, vol. 28, no. 1, p. 275–285
Ground surface temperatures (GST) are widely measured in mountain permafrost areas, but their time series data can be interrupted by gaps. Gaps complicate the calculation of aggregates and indices required for analysing temporal and spatial variability between loggers and sites. We present an algorithm to estimate daily mean GST and the resulting uncertainty. The algorithm is designed to...
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In: Geomorphology, 2011, vol. 132, no. 3-4, p. 208-221
In order to determine the spatial extension and the characteristics of permafrost within alpine talus slopes, two sites located in the western part of the Swiss Alps were studied using borehole drilling and electrical resistivity tomography (ERT) profiles. Three boreholes were drilled along an upslope–downslope transect in both talus slopes. In both sites, frozen sediments are present only in...
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In: Remote Sensing of Environment, 2011, p. -
Surface subsidence associated with the construction of a headrace tunnel in the Swiss Alps at more than 2000 m above sea level (a.s.l.) has been detected at two locations with satellite differential Synthetic Aperture Radar (SAR) interferometry. At the first location, a subsidence trough of about 4 cm in the satellite line-of-sight direction following the headrace tunnel axes has been measured...
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In: The Open Geology Journal, 2007, vol. 2, p. 18-29
Dendrogeomorphological analyses of trees affected by debris flows have regularly been used to date past events. However, while previous studies in the Swiss Alps have focused primarily on granitic and gneissic debris-flow material and on Larix decidua Mill. and Picea abies (L.) Karst. trees, they have – at the same time – widely disregarded torrents dominated by finely fractured calcareous...
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In: Global and Planetary Change, 2008, vol. 60, no. 3-4, p. 222-234
Debris-flow activity on the forested cone of the Ritigraben torrent (Valais, Swiss Alps) was assessed from growth disturbances in century-old trees, providing an unusually complete record of past events and deposition of material. The study of 2246 tree-ring sequences sampled from 1102 Larix decidua Mill., Picea abies (L.) Karst. and Pinus cembra ssp. sibirica trees allowed reconstruction of 123...
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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: Zeitschrift für Geomorphologie, 2005, vol. 49, no. 1, p. 89-106
Dendrochronology was used to study 25 years of rockfall activity on a forested slope at Täschgufer, Täsch (Swiss Alps). We introduce a new approach by evaluating the initiation of callous tissue and resin duct formation after rockfall occurrence to determine the seasonal timing of events. Results from 270 stem discs of 18 Larix decidua Mill. trees show distinct seasonal differences in...
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In: Flora - Morphology, Distribution, Functional Ecology of Plants, 2004, vol. 99(1), p. 70
We tested whether alpine plants increase their effort to attract pollinators to compensate for assumed pollinator scarcity at high altitude. A three times larger fraction of the shoot was allocated to flowers in alpine plants (30 species, 2700m asl) compared to lowland plants (20 species, 600m asl), while leaf mass fraction did not differ between the altitudes. At high elevation, a three times...
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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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