Message to propective students  
 

Research in my lab focuses on problems of scales and on the study of local interactions in marine systems. Students interested to apply for graduate studies in my lab should send their application to frederic.guichard@mcgill.ca including their full CV and a brief statement about their research interests. Information about how to apply for graduate studies at McGill can be found in the graduate studies section of the McGill Biology website.

Research Interests

 
 

I am interested in the study ecosystems as complex systems and in problems of scale in ecology. Among these problems I am interested in understanding (1) how large scale patterns of biological diversity develop and are maintained from local interactions among individuals, (2) how biological diversity is influenced by global changes, (3) the role of biological diversity for community structure and dynamics, and (4) how environmental complexity interact with biotic processes to maintain variability and diversity in communities. I address these questions by combining empirical (experiments, remote sensing) and theoretical (spatially-explicit modeling) approaches in order to link patterns and processes across scales. More precisely, much of my research is focused on understanding how diversity and other properties of marine communities emerge from local interactions among individuals.

One of the main goal of my research is to understand how the aggregation of species and space into functional groups or "community elements'' can provide nontrivial information about community dynamics. I develop spatially-explicit models and simulations implementing local processes tested in the field. One of the questions underlying this work is to determine conditions maintaining communities in a critical state where scale invariance (i.e. power law relationships) are observed, and to understand the role of functional diversity in that process. I also use models to explore the role of metacommunity dynamics (large scale interactions among communities through larval dispersal) along biogeographic physical gradients for the maintenance of local and regional diversity. The development of metacommunity models is of great interest in coastal habitats in order to understand the influence of global changes on biological diversity. Another advantage of large-scale models is their use as a tool for the design of marine reserves. Linking patterns and processes responsible for creating and maintaining diversity must cover a wide range of spatial scales.

I base my research on the use of different approaches, each addressing a specific range of scales. These approaches include spatial modeling, remote sensing, molecular, and field survey data. As experiments allow to rigorously test local processes, I developed remote sensing techniques that provide patterns from the scale of experiments to regional scales. Spatially-explicit models then explore the importance of tested processes at the small scale for the large scale dynamics and spatial structure of communities.

Ongoing Projects  
 

1. Metacommunity dynamics across scales and the design of marine reserve networks (NSERC Discovery; 2012-2017)

Marine reserve design theory is currently lacking integration between community structure and spatial coupling through larval dispersal. Projects will explore the role of functional (community structure) and spatial (dispersal) coupling among sites on (1) the emergence of patterns at biogeographic scales and (2) the consequences of these patterns on the persistence of coastal communities in fragmented habitats resulting for marine reserve networks. The objective of these projects will be to build a theory for the design of marine reserve networks that explicitly addresses feed-backs between large-scale dispersal and local interspecific interactions. Projects involve the development of spatially-explicit metacommunity models and analysis of oceanographic and distribution data at the biogeographic scale.

2. Non-equilibrium Meta-ecosystem theories (NSERC Discovery; 2012-2017)

The goal of the proposed research is to develop and test a non-equilibrium theory of large-scale ecosystems with explicit consideration of spatial flows of individuals and matter. Our understanding of natural ecosystems has progressed from the study of local ecological interactions to theories integrating spatial movement and interactions of individuals across scales. However, well-documented flows of organic and inorganic matter in coastal waters, are still not well integrated into predictions of regional population persistence and biodiversity. The research will first develop a general non-equilibrium theory of meta-ecosystems. We will adopt a coupled-oscillator approach to approximate and simplify the model as phase dynamics that can describe relationships between many non-equilibrium coupled systems. This formalism will allow the prediction of regional ecosystem functions and of spatiotemporal heterogeneity as spatial asynchrony through the interaction between fluxes of individuals and matter. We will use intertidal mussel beds as a model system and conduct mesocosm experiments with metabolic chambers to test the role of simple competitive and trophic interactions among mussels and with dominant associated species for fluxes driving ecosystem functions (e.g. oxygen, ammonium, chlorophyll a). The goal of these experiments will be to test for feedbacks between population-level connectivity and ecosystem functions. Experimental results will be integrated into a specific theory of coastal meta-ecosystems, and we will predict spatial synchrony between fluctuations of organic and inorganic matter. We will validate our predictions by conducting a large-scale (150km) field survey along the south shore of the St. Lawrence Estuary and from existing (e.g. CHONe, LTER, PISCO) datasets. These theories and results will provide a more general theory of ecosystem-based management and of marine reserve networks where size and spacing of reserves are optimized for interconnections among populations and matter over regional scales that are relevant to policy makers and managers.

3. Canadian Healthy Oceans Network - CHONe [visit website]

  • Project 1: Meta-ecosystems in theory and practice: Scaling up biodiversity-productivity relationships in spatially-structured benthic habitat.
  • Project 2: The dynamics of dispersal: multiple methodologies to predict uncertainty and metapopulation resilience


4. Optimizing networks of marine protected areas: combining genetic connectivity and biophysical models (NSERC Strategic project; PI: Marie-Josée Fortin, U Toronto)

(i) Improve current estimation of genetic connectivity across seascapes

(ii) Develop predictive scenarios of how genetic connectivity might change with climate change and increasing fishing pressure

(iii) Assess how current and future MPA network designs integrate current and future connectivity to optimize protection efforts


Other projects involve theoretical explorations of self-organization and nonlinear dynamics in disturbed ecosystems, field studies testing the coupling between local production and recruitment in coastal systems, and the development of transport models used to derive statistical distribution of larval dispersal.

 
 
Last update: June 20, 2016