The axis “(TE) NORM & Biocenoses” of the Zone Atelier Territoires Uranifères (ZATU, https://zatu.org/) has the ambition to carry out projects which will make it possible to lift conceptual and methodological scientific locks in the determination and understanding on the impact of natural radioactivity and radionuclides on biocenosis.

An important issue in biotopes, characterized by low-dose release of radionuclides following anthropogenic activity ((TE) NORM), is their transfer to living organisms and its consequences on the biocenoses inhabiting these biotopes. Recent studies have shown that diatom species in natural radioactive mineral sources in Auvergne present deformations in their external silica skeleton (frustule). In addition, the diatom frustule is suitable for studying the transfer mechanisms of radionuclides.

Thus, we propose to study, through a thesis funded by the CNRS (Doctoral Contract, CNRS), the diatom communities in the ATELIER site (Rophin mine), more specifically from upstream to downstream of a stream characterized by a gradient of radioactivity. We will compare the communities of diatoms living in ATELIER site to those living in naturally occurring radioactive biotopes (i.e. mineral springs (ZATU observatories)) with the aim to determine if the origin of the radioactivity has a specific impact. A second part of the thesis will focus on the analysis of the fossil diatom communities that populated the ATELIER site and the observatory sites of the ZATU in order to determine the impact (or not) of the exploitation of the uranium mine on the structuring and the functioning of diatom communities in these biotopes.

We are looking for motivated candidates. Please circulate this offer to your graduates (Master II) in search of a thesis subject. Interested candidates can contact us for more information: Aude BEAUGER (Aude.Beauger@uca.fr), David Biron (David.Biron@uca.fr).

All candidates must apply on the job site of the CNRS (https://emploi.cnrs.fr/) and for our thesis subject (Reference: UMR6023-DAVBIR-001) on this link (https://emploi.cnrs.fr /Offres/Doctorant/UMR6023-DAVBIR-001/Default.aspx). Below is general information on the Doctoral Contract offer