Job description: Postdoctoral fellowship in modeling phosphorus soil
We are looking for a motivated post doc fellow interested in soil biogeochemistry and land
surface modeling to join our team at LSCE. The increase of atmospheric CO2 and climate change, associated to regional increases in nitrogen (N) and phosphorous (P) deposition induce a modification of the soil microbial and fungi activities impacting the mineralization of nutrients (N, P) and the stability of soil organic carbon. The post doc will combine two recent developments incorporated in the process-based ecosystem model ORCHIDEE: (a) the explicit representation of phosphorus and nitrogen cycles and their interactions with the environment and (b) a new soil carbon decomposition module including vertical and lateral transport and priming effects. The post doc will incorporate mechanisms related to microbial and fungi impacts on the stoichiometry of mineralization products, and inorganic N and P diffusion in the soil in relation to plant uptake.
The model will be evaluated at sites with long term N and P additions experiments collected in the IMBLANCE-P project, to quantify the importance of limitations from phosphorous
mineralization and diffusion in soil to support primary production and the role of priming in the mineralization and plant uptake of N and P under additional N and P input, elevated atmospheric CO2 and warming. Candidates should hold a PhD in ecology, soil science, Earth System Modeling or environmental.
Postdoctoral fellowship in modeling of the phosphorus cycle in the
We seek a motivated postdoctoral fellow to join a collaborative research effort to understand the role of nutrient limitation in explaining the observed decline of Amazonian
carbon uptake and inter-site variability. In the absence of nutrient limitation, we predict an
increase in the carbon uptake by ecosystems via biomass accumulation due to the CO 2
fertilization, as well as a drought-induced mortality risk, but this is not well captured in models.
The postdoctoral fellow will investigate how productivity and biomass turnover are affected
by the low soil P concentrations in Amazonia and if increasing nutrient limitation can explain the observed trend in Amazon carbon sink and their impact on its future evolution. He/she will make extensive use of the process-based grid-based ecosystem model ORCHIDEE (Krinner et al., 2005), which was recently extended by representations of the cycles of phosphorus and nitrogen, and their interactions with environmental conditions. Model predictions will be tested against the unique long-term observational data acquired in French Guiana over more than 100 ha of permanent forest plots (http://paracou.cirad.fr/experimental-design/guyafor-network). This project is jointly funded by the Imbalance-P ERC-Synergy project (http://imbalancep-erc.creaf.cat/), and by the laboratory of excellence CEBA (Center for the study of Biodiversity in Amazonia; http://www.labex-ceba.fr/en/).
IMBALANCE-P: Quantifying the responses of ecosystems and society in a world increasingly rich in N and C but limited in P
TERRABITES: Cross-disciplinary assessment of our current understanding of the terrestrial biosphere from an Earth system perspective to improve the reliability of future Earth system projections in coupled climate-biosphere simulations.
Working group 1: Modeling Plant Functioning
CliSAP – Integrated Climate System Analysis and Prediction:
B2 Land use and land cover change: interrelationships between anthropogenic land management and climate.