Affiner les résultats


Université de Fribourg

Imprisoned in the Cretan mountains: How relict Zelkova abelicea (Ulmaceae) trees cope with Mediterranean climate

Fazan, Laurence ; Guillet, Sébastien ; Corona, Christophe ; Kozlowski, Gregor ; Stoffel, Markus

In: Science of The Total Environment, 2017, vol. 599–600, no. Supplement C, p. 797–805

We investigate the sensitivity of the relict, endemic Cretan tree species Zelkova abelicea (Lam.) Boiss. (Ulmaceae) to several climate variables (temperature, precipitation and drought). For this purpose, we establish the first centennial tree-ring chronology for the species, and the first ever tree-ring chronology for a broadleaved species on Crete. We demonstrate the strong sensitivity of...

Université de Fribourg

Fighting their last stand? A global analysis of the distribution and conservation status of gymnosperms

Fragnière, Yann ; Bétrisey, Sébastien ; Cardinaux, Léonard ; Stoffel, Markus ; Kozlowski, Gregor

In: Journal of Biogeography, 2015, vol. 42, no. 5, p. 809–820

Aim: Gymnosperms are often described as a marginal and threatened group, members of which tend to be out-competed by angiosperms and which therefore preferentially persist at higher latitudes and elevations. The aim of our synthesis was to test these statements by investigating the global latitudinal and elevational distribution of gymnosperms, as well as their conservation status, using all...

Université de Fribourg

Estimating the volume of glaciers in the Himalayan–Karakoram region using different methods

Frey, H. ; Machguth, Horst ; Huss, Matthias ; Huggel, C. ; Bajracharya, S. ; Bolch, T. ; Kulkarni, A. ; Linsbauer, Andreas ; Salzmann, Nadine ; Stoffel, Markus

In: The Cryosphere, 2014, vol. 8, no. 6, p. 2313–2333

Ice volume estimates are crucial for assessing water reserves stored in glaciers. Due to its large glacier coverage, such estimates are of particular interest for the Himalayan–Karakoram (HK) region. In this study, different existing methodologies are used to estimate the ice reserves: three area–volume relations, one slope-dependent volume estimation method, and two ice-thickness...

Université de Fribourg

The days of plenty might soon be over in glacierized Central Asian catchments

Sorg, Annina ; Huss, Matthias ; Rohrer, Mario ; Stoffel, Markus

In: Environmental Research Letters, 2014, vol. 9, no. 10, p. 104018

Despite the fact that the fast-growing population of Central Asia strongly depends on glacial melt water for fresh water supply, irrigation and hydropower production, the impact of glacier shrinkage on water availability remains poorly understood. With an annual area loss of 0.36 to 0.76%, glaciers are retreating particularly fast in the northern Tien Shan, thus causing concern about future water...

Université de Fribourg

Data and knowledge gaps in glacier, snow and related runoff research – A climate change adaptation perspective

Salzmann, Nadine ; Huggel, Christian ; Rohrer, Mario ; Stoffel, Markus

In: Journal of Hydrology, 2014, vol. 518, Part B, p. 225–234

Glacier and snow cover changes with related impacts on melt runoff can seriously affect human societies which are depending on fresh water from cryospheric sources. Observed trends and projected future evolutions of climatic and cryospheric variables clearly show the need to adapt to these changes. Accordingly, the topics addressed herein have been put on the agendas of many larger funding...

Université de Fribourg

Hydrophobia of gymnosperms: myth or reality? A global analysis

Kozlowski, Gregor ; Stoffel, Markus ; Bétrisey, Sébastien ; Cardinaux, Léonard ; Mota, Matteo

In: Ecohydrology, 2014, p. –

According to the classical textbooks, the gymnosperms are the only seed plants without aquatic species. Recently, however, a set of virtually complete compilations on gymnosperms has been published, enabling a new evaluation of the putative hydrophobia of gymnosperms. This synthesis aims at portraying the relation of all extant gymnosperm species to aquatic and wetland habitats. We present a...

Université de Fribourg

Fine-scale spatial patterns of the Tertiary relict Zelkova abelicea (Ulmaceae) indicate possible processes contributing to its persistence to climate changes

Bosque, Marta ; Adamogianni, Maria Irene ; Bariotakis, Michael ; Fazan, Laurence ; Stoffel, Markus ; Garfi, Giuseppe ; Gratzfeld, Joachim ; Kozlowski, Gregor ; Pirintsos, Stergios

In: Regional Environmental Change, 2014, vol. 14, no. 2, p. 835–849

In this paper, the fine-scale spatial patterns of the Tertiary relict Zelkova abelicea (Lam.) Boiss. were studied (1) to reveal processes that contributed to its persistence to climate changes and (2) to assist future conservation planning, with the purpose of shifting the attention of conservation practitioners from patterns to processes. Results of the fine-scale spatial patterns of Z. abelicea...