McGill University
Candidat M.Sc.
superviseur(e): Frederic Guichard
Philipe Archambault
Début: 2018-09-08
Fin: 2020-06-01

Projet

Coupling Structural and Functional Stability in Ecosystem Engineered Environments
The goal of my thesis is to investigate the coupling between the aspects of structural stability and functional stability and whether they are coupled in a predictable way over the succession of a mussel bed community. Mussels being ecosystem engineers provide a solid model to observe this coupling as they are crucial to the origin and maintenance of these complex intertidal food webs. They are the first colonizers; providing a solid foothold and wave break for later colonization. However, they do not simply provide the physical foundation. Mussels are efficient filter feeders greatly impacting the turnover and sequestration of nutrients between the pelagic and benthic habitats. While some nutrients are secreted directly into the water column by the mussels the vast majority of consumed biomass is sequestered in the sediment as feces and pseudo-feces. The sediment creates an appealing habitat encouraging the recruitment of benthic invertebrates. This leads us to a defining theory of ecological stability, the idea that increasing the diversity and complexity within a community leads to an overall increase in stability. This will be contrasted with observations of ice scoured shores as a potential destabilizing force on these ecosystems. We will investigate and compare multiple metrics both of energy flow (functional) and the physical attributes (structural) to uncover the underlying relationships governing the stability and succession of ecosystem engineered communities.

Mots-clés

aquatic ecology, benthic ecology, community stability, food webs