| Project Detail |
Copper (Cu), nickel (Ni), and zinc (Zn) are essential micronutrients for phytoplankton growth and directly influence the biological carbon pump, which sequesters about 10 billion tons of carbon per year, thereby limiting climate warming. Although intrinsically linked with the oceanic carbon cycle, their marine biogeochemical cycles are not fully understood. The role of oceanic margins, which modulate the transfer of these trace metals (TMs) between land and ocean, is critically under-constrained. The overarching objective of IsoMargin is to characterise and quantify the fluxes of micronutrients from the sediments at the margins. I will contribute to this effort by using a novel multiple-metal concentration and isotope system (Cu, Ni, Zn) on dissolved and particulate phases (suspended particles and marine sediment) using both field and experimental approaches. The oceanic behaviours of these three TMs are distinct enough to respond differently to specific processes, generating complementary information. Hosted by the CNRS-LEGOS, I will produce the first database of Cu, Ni, Zn concentrations and isotope compositions in both dissolved and particulate phases above and off two margins of the Indian Ocean. These observations will be completed by new measurements of TM isotope signatures induced by sediment dissolution in controlled experiments. The experimental data will be integrated into a thermodynamic model, allowing a better description of the transfer mechanisms between the sediment and dissolved pools and thus a broader application of my findings. This project is in line with the Horizon Europe programme priority “exploring and forecasting the impacts of climate change” and the GEOTRACES programme. My close involvement in the leadership and management of this project will promote me as an independent and mature career researcher in marine geochemistry. The data and science products will be open source, and I will share my knowledge via dedicated outreach actions. |
