The Info&Sols Unit is looking for a PhD student for a thesis on the analysis of changes in soil organic carbon.

Working environment, missions and activities

Increasing the organic carbon content of agricultural soils has been presented as an interesting way of mitigating climate change. However, little is known about the response of changing systems that vary widely across the country in terms of climate, soil type, use and cultivation practices. There is therefore a major challenge in gaining a better understanding of past trends in soil organic carbon content, by describing the type of change and its timing for a range of soil and climate conditions across France. Linking these trajectories to changes in practices or use would make it possible to improve recommendations for better soil management. The aim of this thesis is therefore to quantify, spatialise and understand the dynamics of changes in organic carbon content in agricultural soils in mainland France since the 1990s. France has a particularly powerful tool for observing temporal changes in the physico-chemical properties of agricultural soils, the Soil test Database (BDAT). This database, managed by INRAE Info&Sols and containing more than 3.5 million organic carbon determinations, will be used and linked to a soil map covering the whole of France, the 1:250,000 French soil survey (, Référentiel Régional Pédologique, IGCS programme). This spatial support will make it possible to interpret the factors influencing changes in organic carbon content in relation to different soil contexts. Statistical and geostatistical methods will be used to quantify temporal variations and the associated uncertainty, and to map them on a national scale. A spatio-temporal Bayesian inference model (INLA-SPDE) could be used, for example. Temporal variations will be interpreted taking into account local conditions, with regard to agronomic indicators that will have to be constructed, climate, soil properties or soil type.

The successful candidate will work in the INRAE Info&Sols research unit in Orléans, specialised in soil knowledge and the statistical and spatial data processing, under the supervision of Antonio Bispo, Hocine Bourennane, Eva Rabot and Nicolas Saby.

Specific conditions of activity: A 3-month stay abroad must be completed.

Selection process

The thesis is funded. The directors and those responsible for the thesis will select three candidates after studying their applications and following an interview. The selected candidates will be auditioned in person, between 5 and 8 May 2025, by a jury from the EMSTU doctoral school, which will establish the final ranking.

Training and skills required

Recommended training: Master 2 or engineering degree in soil science, agronomy, the environment, mathematics or IT.

Knowledge required: Depending on the candidate's specialism, subject knowledge in soil science (soil classification, pedology), agronomy and/or skills in the use of digital tools on large datasets (databases, statistics, geostatistics, geomatics, programming).

Skills required: Ability to take the initiative, creativity, thoroughness, ability to write and express oneself, taste for digital approaches.

How to apply

Please apply via the doctoral school website : https://collegedoctoral-cvl.fr/as/ed/voirproposition.pl?site=CDCVL&matricule_prop=62581

Deadline : 13 April 2025