photographist

“Foraminifera are unicellular microorganisms that are half a millimetre wide and that have the ability to produce a carbonate shell that can record the environmental conditions around it. This shell is an extremely useful tool used in geology and palaeoclimatology to reconstruct ancient climates. These organisms live in the sea, so we are also oceanographers when working on foraminifera. These foraminifera are able to live without oxygen. When the oxygen runs out they get energy by breathing nitrates, another element present in water and sediment. To understand the process of denitrification, I am going to incubate my foraminifera in a laboratory, at different oxygen concentrations, and then make cytological sections and observe which organelles in their cells allow this process, which is common to all bacteria, to occur.

These microorganisms have existed for more than 600 million years. We know of around 50,000 fossilised species and 5,000 living species. They are useful for monitoring the ocean environment. As they have a shell, by taking a core sample from the sediment, we can track back to the pre-anthropogenic period and reconstruct a reference condition – proof of a pollution free environment. Faced with organic pollution such as sewage waste, oil around oil rigs or from oil spills, these organisms will have different ecological requirements. Therefore, we will have an idea of the intensity and the spatial distribution of the pollution in the ocean environment thanks to these foraminifera. When we have succeeded in standardising our data thanks to our research, it will be used by research offices in which our future PHD students can continue this work using their specialist skills.”

Emmanuelle Geslin
Senior Lecturer, University of Angers

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