Phycosphere Fe · Iron speciation in the microenvironment surrounding phytoplankton cells and the consequences for Fe bioavailability
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2020-11-01 → 2023-10-31
- EU contribution
- €174,806
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Iron speciation in the microenvironment surrounding phytoplankton cells and the consequences for Fe bioavailability
More than a half of atmospheric CO2 on earth is taken up by phytoplankton, but iron (Fe) limits their growth in large regions of the oceans. Ongoing ocean acidification and global warming would influence Fe-stress in marine phytoplankton and hence the biological carbon fixation. Key existing knowledge gaps are the pathways by which phytoplankton take up Fe, and influences of chemical conditions in the microenvironment surrounding algal cells (i.e., phycosphere) on Fe speciation and bioavailability. This knowledge represents an impediment to understanding the complex effects of climate change on Fe uptake and oceanic carbon fixation. The overall objective of the project is to understand the relationship between Fe speciation in the phycosphere and Fe bioavailability to phytoplankton under different ocean conditions. The data are key to the assessment of Fe availability to phytoplankton in current and future oceans, and it would improve our ability to model phytoplankton dynamics and predict biological carbon fixation in a changing ocean. Data from this project show that even in the algae cells of ~5 µm diameter, the pH in the phycosphere is consistently different from bulk seawater. For the first time, it shows that the thickness of the pH boundary layer around phytoplankton cells is largely amplified by ocean acidification. Moreover, the modelling results suggest that the local pH alters Fe speciation in this microenvironment, and in a future more acidic ocean, a much thicker boundary layer would result in a larger deviation of the Fe speciation in the phycosphere from bulk seawater. Overall, this project suggests that precise quantification of chemical conditions in the phycosphere is crucial for better understanding how phytoplankton will respond to environmental changes.
Data: CORDIS, © European Union
Project objective
The interaction between metals and microscopic plant-like organisms called phytoplankton is a key link to global carbon balance. More than a half of atmospheric CO2 on earth is taken up by phytoplankton, but iron (Fe) limits their growth in large regions of the oceans. Ongoing ocean acidification and global warming will influence Fe-stress in marine phytoplankton and hence the biological carbon fixation. Key existing knowledge gaps are the pathways by which phytoplankton take up Fe, and influences of chemical conditions in the microenvironment surrounding algal cells (i.e., phycosphere) on Fe speciation and bioavailability. This knowledge represents an impediment to understanding the complex effects of climate change on Fe uptake and oceanic carbon fixation. The project ‘Phycosphere Fe’ will determine chemical conditions and Fe speciation in the phycosphere of model phytoplankton species, quantify the role of phycosphere Fe speciation in Fe bioavailability, and investigate influences of climate change (i.e., warming and increased CO2) on Fe-algae interfacial processes. The project is key to the assessment of Fe bioavailability, growth and CO2 fixation of phytoplankton in current and future oceans, which make key contributions to global carbon sequestration. The project will improve our ability to model phytoplankton dynamics and predict biological carbon fixation in a changing ocean.
Original text from CORDIS.
Participants
- HELMHOLTZ-ZENTRUM FUR OZEANFORSCHUNG KIEL (GEOMAR) · KielCoordinatorGermany
Links
Data: CORDIS, © European Union