Université de Fribourg

Temperature and trophic structure are driving microbial productivity along a biogeographical gradient

Gray, Sarah M. ; Poisot, Timothée ; Harvey, Eric ; Mouquet, Nicolas ; Miller, Thomas E. ; Gravel, Dominique

In: Ecography, 2016, vol. 39, no. 10, p. 981–989

Temperature is known to influence ecosystem processes through its direct effect on biological rates such as respiration and nutrient cycling. These changes can then indirectly affect ecologically processes by altering trophic dynamics, the persistence of a species in a given environment, and, consequently, its distribution. However, it is not known if this direct effect of temperature on...

Université de Fribourg

Mismatch in microbial food webs: predators but not prey perform better in their local biotic and abiotic conditions

Parain, Elodie C. ; Gravel, Dominique ; Rohr, Rudolf P. ; Bersier, Louis-Félix ; Gray, Sarah M.

In: Ecology and Evolution, 2016, vol. 6, no. 14, p. 4885–4897

Understanding how trophic levels respond to changes in abiotic and biotic conditions is key for predicting how food webs will react to environmental perturbations. Different trophic levels may respond disproportionately to change, with lower levels more likely to react faster, as they typically consist of smaller-bodied species with higher reproductive rates. This response could cause a...

Université de Fribourg

Succession in the aquatic Sarracenia purpurea community : deterministic or driven by contingency?

Gray, Sarah M.

In: Aquatic Ecology, 2012, vol. 46, no. 4, p. 487-499

The development of a community through time, or succession, is generally described as the orderly replacement of species until a deterministic, stable endpoint is reached. However, stochastic factors, coupled with intrinsic biotic factors, such as herbivory or predation, can cause communities within the same habitat to become highly dissimilar in composition. Much research on the succession of...