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Université de Fribourg

A new model for global glacier change and sea-level rise

Huss, Matthias ; Hock, Regine

In: Cryospheric Sciences, 2015, p. 54

The anticipated retreat of glaciers around the globe will pose far-reaching challenges to the management of fresh water resources and significantly contribute to sea-level rise within the coming decades. Here, we present a new model for calculating the twenty-first century mass changes of all glaciers on Earth outside the ice sheets. The Global Glacier Evolution Model (GloGEM) includes mass loss...

Université de Fribourg

New long-term mass-balance series for the Swiss Alps

Huss, Matthias ; Dhulst, Laurie ; Bauder, Andreas

In: Journal of Glaciology, 2015, vol. 61, no. 227, p. 551–562

In this study we present 19 new or re-analysed series of glacier-wide seasonal mass balance for the Swiss Alps based on direct measurements. The records partly start around 1920 and continue until today. Previously unpublished and unevaluated observations of point winter and annual balance are compiled from various sources and archives. These highly valuable datasets have not yet been...

Université de Fribourg

Biological Flora of the British Isles: Ambrosia artemisiifolia

Essl, Franz ; Biró, Krisztina ; Brandes, Dietmar ; Broennimann, Olivier ; Bullock, James M. ; Chapman, Daniel S. ; Chauvel, Bruno ; Dullinger, Stefan ; Fumanal, Boris ; Guisan, Antoine ; Karrer, Gerhard ; Kazinczi, Gabriella ; Kueffer, Christoph ; Laitung, Beryl ; Lavoie, Claude ; Leitner, Michael ; Mang, Thomas ; Moser, Dietmar ; Müller-Schärer, Heinz ; Petitpierre, Blaise ; Richter, Robert ; Schaffner, Urs ; Smith, Matt ; Starfinger, Uwe ; Vautard, Robert ; Vogl, Gero ; Lippe, Moritz von der ; Follak, Swen

In: Journal of Ecology, 2015, vol. 103, no. 4, p. 1069–1098

This account presents information on all aspects of the biology of Ambrosia artemisiifolia L. (Common ragweed) that are relevant to understanding its ecology. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral...

Université de Fribourg

Quarantine arthropod invasions in Europe: the role of climate, hosts and propagule pressure

Bacon, Steven J. ; Aebi, Alexandre ; Calanca, Pierluigi ; Bacher, Sven

In: Diversity and Distributions, 2014, vol. 20, no. 1, p. 84-89

Aim: To quantify the relative importance of propagule pressure, climate-matching and host availability for the invasion of agricultural pest arthropods in Europe and to forecast newly emerging pest species and European areas with the highest risk of arthropod invasion under current climate and a future climate scenario (A1F1).Location: Europe.Methods: We quantified propagule pressure,...

Université de Fribourg

Genomic and phenotypic architecture of a spruce hybrid zone (Picea sitchensis × P. glauca)

Hamilton, Jill A. ; Lexer, Christian ; Aitken, Sally N.

In: Molecular Ecology, 2012, p. -

Interspecific hybridization may enhance the capacity of populations to adapt to changing environments, and has practical implications for reforestation. We use genome-wide estimates of admixture and phenotypic traits for trees in a common garden to examine the extent and direction of gene flow across a Picea hybrid zone, testing assumptions of the bounded hybrid superiority and tension zone...

Université de Fribourg

Unraveling the patterns of late Holocene debris-flow activity on a cone in the Swiss Alps: chronology, environment and implications for the future

Stoffel, Markus ; Conus, Delphine ; Grichting, Michael A. ; Lièvre, Igor ; Maître, Gilles

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...

Université de Fribourg

400 years of debris flow activity and triggering weather conditions: Ritigraben VS, Switzerland

Stoffel, Markus ; Lièvre, Igor ; Conus, Delphine ; Grichting, Michael A. ; Raetzo, Hugo ; Gärtner, Holger W. ; Monbaron, Michel

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...

Université de Fribourg

Evidence of response of vegetation to environmental change on high-elevation sites in the Swiss Alps

Keller, Franciska ; Kienast, F. ; Beniston, Martin

In: Regional Environmental Change, 2000, vol. 1(2), p. 70

Climate change has in the past led to shifts in vegetation patterns; in a future, warmer climate due to enhanced greenhouse-gas concentrations, vegetation is also likely to be highly responsive to such warming. Mountain regions are considered to be particularly sensitive to such changes. In this paper we present an approach to assess the impact of climate change on long-term vegetation plots...

Université de Fribourg

Climate modeling at various spatial and temporal scales : where can dendrochronology help ?

Beniston, Martin

In: Dendrochronologia, 2002, vol. 20, no. 1, p. 117-131

This paper provides a brief overview of certain issues related to climate modeling and the role that dendrochronology can play, and has already played, in this context. Modeling is an essential approach to investigating the future evolution of the climate system in response to human activities. Tree-ring chronologies, on the other hand, have the capability of providing key parameters for...