Date

November 3, 2023

Time

3:00 pm

Location

ESB149 & Zoom

Guest speaker: Frédéric Guichard, McGill University
Host: B. Gilbert

Abstract:
Ecosystem dynamics are based on processes such as the cycling and spatial flows of matter that elude the study of food web networks based on trophic interactions. Instead, ecological interactions must integrate spatial flows across heterogeneous habitats, and non-trophic interactions that reflect higher-order interactions among species and non-living compartments. I will present recent and ongoing research on meta-ecosystem theory showing how the explicit interaction between the cycling and spatial flows of matter can shape regional species coexistence and ecosystem functions through the emergence of spatially heterogeneous trophic cascades. I will then present a model of local ecosystem dynamics with foundation species where higher-order interactions are introduced to study the dual role of matter as resource and habitat. Results from this ongoing research reveal the existence of habitat and resource limitation regimes that have important impacts on ecosystem stability and productivity. Together these results suggest topological constraints on the cycling of matter as imposed by spatial structure and foundation species can lead to strong interactions with trophic regulation. I will discuss how these findings apply to coastal ecosystems such as seagrass meadows where both spatial structure and foundation species are key components.