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Université de Fribourg

The effect of top‐predator presence and phenotype on aquatic microbial communities

Sullam, Karen E. ; Matthews, Blake ; Aebischer, Thierry ; Seehausen, Ole ; Bürgmann, Helmut

In: Ecology and Evolution, 2017, vol. 7, no. 5, p. 1572–1582

The presence of predators can impact a variety of organisms within the ecosystem, including microorganisms. Because the effects of fish predators and their phenotypic differences on microbial communities have not received much attention, we tested how the presence/absence, genotype, and plasticity of the predatory three-spine stickleback (Gasterosteus aculeatus) influence aquatic microbes in...

Université de Fribourg

Troubling travellers: are ecologically harmful alien species associated with particular introduction pathways?

Pergl, Jan ; Pyšek, Petr ; Bacher, Sven ; Essl, Franz ; Genovesi, Piero ; Harrower, Colin A. ; Hulme, Philip E. ; Jeschke, Jonathan M. ; Kenis, Marc ; Kühn, Ingolf ; Perglová, Irena ; Rabitsch, Wolfgang ; Roques, Alain ; Roy, David B. ; Roy, Helen E. ; Vilà, Montserrat ; Winter, Marten ; Nentwig, Wolfgang

In: NeoBiota, 2017, vol. 32, p. 1–20

Prioritization of introduction pathways is seen as an important component of the management of biological invasions. We address whether established alien plants, mammals, freshwater fish and terrestrial invertebrates with known ecological impacts are associated with particular introduction pathways (release, escape, contaminant, stowaway, corridor and unaided). We used the information from...

Université de Fribourg

Environmental constraints on Holocene cold‐water coral reef growth off Norway: Insights from a multiproxy approach

Raddatz, Jacek ; Liebetrau, Volker ; Trotter, Julie ; Rüggeberg, Andres ; Flögel, Sascha ; Dullo, Wolf-Christian ; Eisenhauer, Anton ; Voigt, Silke ; McCulloch, Malcolm

In: Paleoceanography, 2016, vol. 31, no. 10, p. 1350–1367

High-latitude cold-water coral (CWC) reefs are particularly susceptible due to enhanced CO₂ uptake in these regions. Using precisely dated (U/Th) CWCs (Lophelia pertusa) retrieved during research cruise POS 391 (Lopphavet 70.6°N, Oslofjord 59°N) we applied boron isotopes (δ¹¹B), Ba/Ca, Li/Mg, and U/Ca ratios to reconstruct the environmental boundary conditions of CWC reef growth. The...

Université de Fribourg

Holocene vegetation and fire history of the mountains of Northern Sicily (Italy)

Tinner, Willy ; Vescovi, Elisa ; Leeuwen, Jacqueline F. N. van ; Colombaroli, Daniele ; Henne, Paul D. ; Kaltenrieder, Petra ; Morales-Molino, César ; Beffa, Giorgia ; Gnaegi, Bettina ; Knaap, W. O. van der ; Mantia, Tommaso La ; Pasta, Salvatore

In: Vegetation History and Archaeobotany, 2016, vol. 25, no. 5, p. 499–519

Knowledge about vegetation and fire history of the mountains of Northern Sicily is scanty. We analysed five sites to fill this gap and used terrestrial plant macrofossils to establish robust radiocarbon chronologies. Palynological records from Gorgo Tondo, Gorgo Lungo, Marcato Cixé, Urgo Pietra Giordano and Gorgo Pollicino show that under natural or near natural conditions, deciduous forests...

Université de Fribourg

Persist or produce: a community trade-off tuned by species evenness

Rohr, Rudolf P. ; Saavedra, Serguei ; Peralta, Guadalupe ; Frost, Carol M. ; Bersier, Louis-Félix ; Bascompte, Jordi ; Tylianakis, Jason M.

In: The American Naturalist, 2016, vol. 188, no. 4, p. 411–422

Understanding the effects of biodiversity on community persistence and productivity is key to managing both natural and production systems. Because rare species face greater danger of extinction, species evenness, a measure of how similar abundances are across species in a community, is seen as a key component of biodiversity. However, previous studies have failed to find a consistent...

Université de Fribourg

Dynamic modelling of the potential habitat loss of endangered species: the case of the Canarian houbara bustard (Chlamydotis undulata fuerteventurae)

Banos-González, Isabel ; Terrer, C. ; Martínez-Fernández, J. ; Esteve-Selma, M. A. ; Carrascal, L. M.

In: European Journal of Wildlife Research, 2016, vol. 62, no. 3, p. 263–275

In this work, we apply a dynamic modelling approach to analyse the habitat loss of the Canarian houbara bustard (Chlamydotis undulata fuerteventurae). This tool allows us to assess the effects of the socio-economic and environmental interactions on the factors threatening the habitat and to carry out a prospective analysis. The results show a potential habitat loss of around 13 % during the...

Université de Fribourg

Neighbour origin and ploidy level drive impact of an alien invasive plant species in a competitive environment

Sun, Yan ; Müller-Schärer, Heinz ; Schaffner, Urs

In: PLOS ONE, 2016, vol. 11, no. 5, p. e0155712

Our understanding of the potential mechanisms driving the spread and naturalization of alien plant species has increased over the past decades, but specific knowledge on the factors contributing to their increased impact in the introduced range is still urgently needed. The native European plant Centaurea stoebe occurs as two cytotypes with different life histories (monocarpic diploids,...

Université de Fribourg

Matching–centrality decomposition and the forecasting of new links in networks

Rohr, Rudolf P. ; Naisbit, Russell E. ; Mazza, Christian ; Bersier, Louis-Félix

In: Proc. R. Soc. B, 2016, vol. 283, no. 1824, p. 20152702

Networks play a prominent role in the study of complex systems of interacting entities in biology, sociology, and economics. Despite this diversity, we demonstrate here that a statistical model decomposing networks into matching and centrality components provides a comprehensive and unifying quantification of their architecture. The matching term quantifies the assortative structure in which node...

Université de Fribourg

Including community composition in biodiversity–productivity models

Sandau, Nadine ; Rohr, Rudolf P. ; Naisbit, Russell E. ; Fabian, Yvonne ; Bruggisser, Odile T. ; Kehrli, Patrik ; Aebi, Alexandre ; Bersier, Louis-Félix

In: Methods in Ecology and Evolution, 2014, vol. 5, no. 8, p. 815–823

Studies on biodiversity and ecosystem functioning (BEF) have elicited debate over the interpretation of the positive relationship between species richness and plant productivity. Manipulating richness cannot be achieved without affecting composition; it is thus essential to consider the latter in statistical models.We firstly review existing approaches that use species richness as an explanatory...

Université de Fribourg

Framework and guidelines for implementing the proposed IUCN Environmental Impact Classification for Alien Taxa (EICAT)

Hawkins, Charlotte L. ; Bacher, Sven ; Essl, Franz ; Hulme, Philip E. ; Jeschke, Jonathan M. ; Kühn, Ingolf ; Kumschick, Sabrina ; Nentwig, Wolfgang ; Pergl, Jan ; Pyšek, Petr ; Rabitsch, Wolfgang ; Richardson, David M. ; Vilà, Montserrat ; Wilson, John R.U. ; Genovesi, Piero ; Blackburn, Tim M.

In: Diversity and Distributions, 2015, vol. 21, no. 11, p. 1360–1363

Recently, Blackburn et al. (2014) developed a simple, objective and transparent method for classifying alien taxa in terms of the magnitude of their detrimental environmental impacts in recipient areas. Here, we present a comprehensive framework and guidelines for implementing this method, which we term the Environmental Impact Classification for Alien Taxa, or EICAT. We detail criteria for...