SedTraceFlux · The critical role of sedimentary trace element fluxes in ocean biogeochemistry
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2021-09-01 → 2023-08-31
- EU contribution
- €191,149
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
The critical role of sedimentary trace element fluxes in ocean biogeochemistry
Understanding the ocean's biogeochemical cycles of trace elements has significant scientific and societal implications. First, many trace elements are vital nutrients for marine organisms. As a result, they can drive evolutionary processes, influence surface climate and environmental conditions by participating in global biogeochemical cycles of carbon and oxygen, and play a key role in maintaining the health of marine ecosystems. Second, trace elements serve as essential tools for investigating the ocean system and tracking its interactions with the biosphere, atmosphere, and lithosphere. Importantly, the isotopic compositions of many trace elements often provide scientists with the only means to reconstruct past ocean environmental conditions, enabling us to study how historical ocean changes have affected the origin and evolution of life on Earth. Consequently, there is a growing effort to incorporate marine trace elements into state-of-the-art global models, aiming to enhance our ability to predict future changes in ocean chemistry and climate. However, these efforts have faced challenges due to our limited understanding of the sources and sinks of dissolved trace elements in the ocean. Recent findings specifically indicate that sedimentary source and sink fluxes may play significantly larger roles in shaping the distributions of marine trace elements than previously assumed. Yet, our knowledge of these fluxes and the relevant sediment biogeochemical processes remains insufficient, resulting in substantial uncertainties in the modern and paleo-applications of trace elements in the field of ocean biogeochemistry. The project aims to characterize the sedimentary processes and fluxes of these trace elements and isotopes, develop new modeling tools to study their biogeochemical cycling in marine sediments and understand the role of sedimentary processes in their global ocean cycles. The project is focused on the rare earth elements and transition metals. The project has concluded that the sedimentary fluxes of trace elements and isotopes are regulated by diagenetic processes including organic matter remineralization, redox cycling, authigenesis, marine silicate weathering and reverse weathering; the sedimentary fluxes contribute significantly to the elemental and isotopic budgets of trace elements and isotopes; including sedimentary processes and fluxes in ocean models is needed to fully explain the distributions of trace elements and isotopes in the ocean.
Data: CORDIS, © European Union
Project objective
Trace elements and isotopes (TEIs) are powerful tools for studying the ocean system and tracing its interaction with the other Earth System components. Many TEIs exert influence on the surface environment by participating in the global carbon and oxygen cycles. Incorporating TEIs into state-of-the-art global models is thus crucial to better predict future changes of ocean biogeochemistry and climate. This effort, however, is hampered by our limited understanding of the source and sink fluxes of TEIs across the sediment-water interface, which are recently hypothesised to play much greater roles in setting the distributions of TEIs in the ocean than previously assumed. Yet insufficient knowledge results in large uncertainties in model implementations of sedimentary fluxes, severely limiting the applications of marine TEIs. The objectives of SedTraceFlux are to constrain the sedimentary TEI fluxes and provide robust parameterizations of such fluxes suitable for global models. This project will focus on iron, neodymium, zinc and their respective isotopes, which are among the most useful TEI tools in oceanography. I will model the chemical speciation and the processes controlling the distributions of these TEIs in sediment pore water and solid phases. The resulting mechanistic parameterizations of sedimentary fluxes will be fine-tuned using Transport Matrix Methods in global biogeochemical modelling. The modelling effort will be complemented by generation of sedimentary Fe data from under-sampled locations. This project represents an ideal synergy between my ability in geochemical modelling and sediment geochemistry, and the expertise of the host group in a broad range of chemical, isotopic and global modelling approaches. It will enhance my innovative potential toward an independent researcher and strengthen the host’s international network and mobility. The results will also help inform the ocean and climate policy-making of the European Union.
Original text from CORDIS.
Participants
- EIDGENOESSISCHE TECHNISCHE HOCHSCHULE ZUERICH · ZuerichCoordinatorSwitzerland
Links
Data: CORDIS, © European Union