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COMPutational PLankton Ecology

Current research activities

The COMPLEx team studies the ecology of marine plankton and the oceanic components of biogeochemical cycles. To perform such studies, we develop quantitative imaging approaches and use metagenomics, at sea and in the laboratory. We exploit the resulting data through computational methods and modelling.

The team’s research is focused on three questions:

We study the relationships between hydrology, biogeochemistry, plankton and organic particles, in global data sets and in long term time series.

We sample through and around fronts and eddies to finely map the distribution of planktonic organisms and marine snow. We propose mechanisms that can explain local accumulations, strong downward flux and connectivity through water masses.

The team conducts approaches based on functional traits (i.e. individual characteristics that influence ecological fitness) extracted from imagery and metagenomic data.


To carry out its research, the team uses three types of tools:

such as the UVP (deployed at sea) and the ZooScan (used in the laboratory) or ZooProcess and EcoTaxa to handle the data they produce. We coordinate the activities of the Quantitative Imagery Platform, which implements these tools at IMEV, and of the Plankton Collection Centre, which stores the corresponding physical samples.

in France and abroad, in order to detect genetic structuring in metapopulations and describe the composition, in species and functions, of open sea communities.

to extrapolate our observation of processes occurring in plankton. The implementation of machine learning methods allows us to accelerate the classification of images, the assignment of functions to sequences, the detection of correlations at large scales, etc.


A little bit of history...

The diversity of plankton in the bay of Villefranche is the reason why a marine station was established there in the 19th century. Systematic monitoring of these populations with traditional methods began in 1966. In the early 1990s, researchers and engineers in Villefranche began to create instruments to record and analyse images of plankton in the ocean and in the laboratory. Those are now used for the weekly plankton monitoring time series carried out in the bay and are part of numerous oceanographic campaigns. Since 2009, quantitative plankton imaging has been coupled with metagenomics through the Tara Oceans campaigns, providing access to rich and complex information that the team now exploits, in collaboration with research groups in France and abroad.