Interests
My research in ecology has focus on the dynamics of zooplankton species from diverse aquatic environments and the role they play at the ecosystem scales. Two recurring themes in my research are the implication of species behavior and life cycle strategy for population and ecosystem dynamics and the contribution of climate change and human pressure to species dynamics.
My interests lay in the comparison of zooplankton from contrasted ecosystem, and the use of different method for the comparison. Methods spread from behaviorism to population dynamics studies with the development of Individual Based Models as the core of my research. The questions I am tackling range from individual consequences to ecosystem response. In particular, my former project focusing on inter-site comparison of limnic ecosystems to study the effect of climate change, investigated at several scales the dynamics of key zooplankters from Lake Biwa (Japan) and lake Geneva (France). |
Approach
Multi-scale approach and virtual copepods
Projects
Hindcast and Forecast of Eurytemora affines habitat in the Seine estuary (France)
Various environmental, anthropogenic and climatic forces directly affect natural habitats in estuarine systems. Estuarine species, particularly those living in the salinity gradient, are concerned by habitat changes that can reduce their fitness. Consequently, efforts to define and monitor potential habitats are required to enable forecasting estuarine species’ future distributions. The present study focuses on the main component of the Seine estuary’s zooplankton, i.e. the calanoid copepod Eurytemora affinis, and aims: (i) to model the functional habitats of three groups of E. affinis developmental stages defined through the life cycle as follows: all larval stages (N1-N6), the first to fourth juvenile stages (C1-C4), and the pre-adult and adults stages (C5-Adults); and (ii) to carry out retrospective analysis, and to test future distributions. For this purpose, we used the previously established model of the environmental envelope for the three developmental stages as a function of salinity and temperature (Dur and Souissi accepted). The spatial dimension was brought by the salinity data from the hydrodynamic model of the Seine estuary (i.e. MARS3D). Data recorded at monitoring buoy were used to simulate the temperature in the Seine estuary for the years 2008-2009-2010. We managed to map the variation at a fine scale (every hour) of the density of the three groups of developmental stage for the three years allowing multiple-scale studies of the variation. To this retrospective aspect, the projection of the habitat of E. affinis was conducted and revealed an upstream progression. These results are in agreement with observations in other estuaries in Europe. Our model can be used to investigate the effect of restoration on this copepod habitat.
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IBM of Egg-carrying copepods to study the response to climate warming
Over the last decade, the phenology of several planktonic copepods has advanced and these shifts were related to climate warming (Edwards and Richardson 2004). Nevertheless, the observed changes were nearby all observed on population from mid- and high latitude region (Ji et al 2010). Compared to temperate species, copepod species from tropical systems may exhibit different reaction norms as expected from the evolution of thermal adaptation to different environments, resulting in different life history patterns (Roff 1992). Such life cycle traits of planktonic species were shown to govern their phenological response to climate warming (Adrian et al. 2006). How do copepods from tropical environments differ from their temperate congeners? To answer such a challenging question, I am investigating the species-specific responses to different scenarios of climate warming. The aim is to identify the underlying processes explaining the variation among species from contrasting ecosystems.
GEISHA
Global Evaluation of the Impacts of Storms on freshwater Habitat and structure of phytoplankton Assemblages.
Future climate change is expected to cause more intense and frequent extreme weather events but we currently only have a basic understanding of how these events might alter freshwater phytoplankton communities. Because storms have strong impacts on thermal stratification and mixing dynamics of lakes, which in turn may influence niche availability and phytoplankton succession, we propose to study the impact of storms on the diversity, including taxonomic and functional composition, of freshwater phytoplankton communities. A thinking group (“Storm-blitz”) has been organized within the Global Lakes Ecological Observatory Network (GLEON) to address questions about the impacts of storms on phytoplankton community through sharing of long-term datasets and high-frequency data in lakes across the globe. GEISHA is built within the Storm-blitz framework and will benefit from the involvement and expertise of this group. The goals of GEISHA are to 1) create the time, space, and resources to work as a cohesive unit, 2) gather and standardize the long-term datasets, 3) perform meta-analyses to evaluate the sensitivity of aquatic ecosystems to extreme weather events, and 4) provide new frameworks to explore theoretical questions related to species diversity and succession in aquatic ecosystems. I am involved in several aspects in this project including defining the effect of storms on the lake physics and on the phytoplankton assemblage succession For more information on GEISHA CESAB web site ; POWELL CENTER web site ; GEISHA website |
Former project
FASCICLE
For further detailed information on the project, visit the FASCICLE website.
Global change poses a strong challenge to ecologists and conservation biologists: even our natural environments become more stressed by the force of climate change and human pressure, we - human - require that this ecosystems produce both a greater quantity and variety of ecosystem services. For instance we may expect lakes to provide clean water, support wild life, and provide more recreational activities, yet at the same time the lake communities is being buffeted by climate change, invasive species and land-use change. In order to ensure that our aquatic ecosystems provide the services society demands we must be able to predict how ecological communities will respond to these global forces, and in turn how changes in community composition will affect ecosystem services. To develop this predictive framework, we employ a mix of observation, experimentation, modeling and synthesis, within planktonic communities.