Joint PhD position: microbes and soil carbon

Microbial controls on soil carbon changes under climate change [3 years PhD thesis]. The Le Laboratoire des Sciences du Climat et de l'Environnement (LSCE) and University Exeter are looking for a motivated candidate for a PhD thesis on Microbial controls on soil carbon changes under climate change. The successful candidate will use land surface models in combination with observations on the response of microbial communities from flagship ecosystem manipulations experiments in the UK, Brazil and elsewhere to assess changes in soil carbon induced by global change drivers.

Background: The response of soil organic carbon to climate change is a major uncertainty in future climate projections. Soil microbes control the decomposition and stabilisation of organic carbon, through their carbon use efficiency (CUE) - the ratio of microbial growth to microbial carbon uptake - regulating losses vs gains in carbon. However, the importance of CUE for soil carbon responses remains uncertain. While CUE varies depending on environmental conditions (nutrients, temperature, etc), this is not considered in models that are used for contemporary and future carbon assessments (e.g. Global Carbon Budget), and remaining carbon budgets to avoid dangerous climate change. As a result, the projections of future response of soil carbon remain highly uncertain.

The PhD project aims to improve Land surface models using a novel global database of

CUE, observed responses from ecosystem manipulations experiments and machine

learning. This includes 

diagnose CUE from existing land surface models and use a novel collection of CUE

• observations to benchmark and constrain the simulated spatial pattern of CUE.
• improve the response of CUE to global change drivers exploiting observations on responses of microbial biomass and soil respiration to changes in soil carbon inputs and soil fertility
• apply the improved models to quantify the future response of soil carbon to climate change

The project is nested within two large international projects CALIPSO (https://calipsovesri.org/) and Global Carbon Budget (https://www.globalcarbonproject.org/) coordinated by the host labs - providing an innovative and inspiring environment.

The PhD project will lead to skills in producing and analysing scientific data from multiple scientific approaches, managing an interdisciplinary project, and scientific communication. The acquired technical skills, academic network and expertise on soil carbon responseglobal change is transferable to various academic and non-academic sectors.

• Academic supervision: Daniel S Goll (LSCE, France) & Stephen Sitch (University Exeter, UK); with additional support from young & senior staff at both locations.
• Work location: The PhD will be jointly hosted by LSCE and University Exeter. A minimum of one year has to be spent at each location. 
• Starting date: Autumn 2024 ( flexible to some extent )
• Salary: in accordance with national regulations including full social and health benefits.

How to apply: Applicants should apply via the ADUM platform to the PhD project: link for application.  Students must create their candidate space and submit the documents required for their application to be examined by the thesis supervisor. If you have any questions about the project please contact: daniel.goll@lsce.ipsl.fr