Altered biogeochemical cycles and their influence on terrestrial and aquatic food webs

PD Dr. Cedric Meunier

Date: October 27, 2021
Time: 2 pm (s.t.)
Place: via zoom. Please register by sending an email to grk2300@uni-goettingen.de.

The human alteration of biogeochemical cycles puts biological systems under enormous pressure, threatening the structure and functioning of food webs. In order to understand how food webs are affected by altered nutrient cycles, a holistic approach is needed to study different trophic levels individually, as well as communities as a whole. Here, I will present a compilation of studies testing the nutrient availability, as well as their ratio (mainly N:P) on marine, freshwater, and terrestrial food webs. Overall, these studies demonstrate that the growth, survival, species distribution, and abundance of organisms within different trophic levels, as well as the interactions between trophic levels, are all influenced by changes in abiotic conditions. I will also show that combining different ecological frameworks, such as ecological stoichiometry and trait-based ecology is a promising approach to yield new insights in the processes governing different organizational levels, from genes to ecosystems. Because the studies presented here demonstrate that simultaneous changes in different abiotic parameters can act in unpredictable synergistic ways that drive food web dynamics, future work should focus on multistressor experiments to determine which new food webs may emerge in response to global change.