Université de Fribourg

Understanding negative biodiversity–ecosystem functioning relationship in semi-natural wildflower strips

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

In: Oecologia, 2019, vol. 189, no. 1, p. 185–197

Studies on biodiversity–ecosystem functioning (BEF) in highly controlled experiments often yield results incompatible with observations from natural systems: experimental results often reveal positive relationships between diversity and productivity, while for natural systems, zero or even negative relationships have been reported. The discrepancy may arise due to a limited or closed local...

Université de Fribourg

The relative contributions of species richness and species composition to ecosystem functioning

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

In: Oikos, 2017, vol. 126, no. 6, p. 782–791

How species diversity influences ecosystem functioning has been the subject of many experiments and remains a key question for ecology and conservation biology. However, the fact that diversity cannot be manipulated without affecting species composition makes this quest methodologically challenging. Here, we evaluate the relative importance of diversity and of composition on biomass...

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

Plant diversity in a nutshell: testing for small-scale effects on trap nesting wild bees and wasps

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

In: Ecosphere, 2014, vol. 5, no. 2, p. art18

Declining plant species richness in agro-ecosystems and thus reduced habitat quality can have cascading effects on ecosystem functioning, leading to reduced pollination and biological control. Here we test if plant diversity can affect arthropod diversity and abundance on a very small scale, manipulating plant species richness (2, 6, 12 and 20 sown species) in small adjacent subplots (6 × 9 m)...

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

Gaps in border controls are related to quarantine alien insect invasions in Europe

Bacon, Steven James ; Bacher, Sven ; Aebi, Alexandre

In: PLoS One, 2012, vol. 7, no. 10, p. e47689

Alien insects are increasingly being dispersed around the world through international trade, causing a multitude of negative environmental impacts and billions of dollars in economic losses annually. Border controls form the last line of defense against invasions, whereby inspectors aim to intercept and stop consignments that are contaminated with harmful alien insects. In Europe, member states...

Université de Fribourg

Diversity protects plant communities against generalist molluscan herbivores

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

In: Ecology and Evolution, 2012, vol. 2, no. 10, p. 2460-2473

Wildflower strips are used to increase natural enemies of crop pests and to conserve insect diversity on farmland. Mollusks, especially slugs, can affect the vegetation development in these strips considerably. Although recent theoretical work suggests that more diverse plant communities will exhibit greater resistance against herbivore pressure, empirical studies are scarce. We conducted a...