Mineral characterization and composition of Fe-rich flocs from wetlands of Iceland: Implications for Fe, C and trace element export ...

In freshwater wetlands, redox interfaces characterized by circumneutral pH, steep gradients in O2, and a continual supply of Fe(II) form ecological niches favorable to microaerophilic iron(II) oxidizing bacteria (FeOB) and the formation of flocs; associations of (a)biotic mineral phases, microorgani...

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Bibliographic Details
Main Authors: Thomas Arrigo, Laurel K., Notini de Andrade, Luiza, Shuster, Jeremiah, Nydegger, Tabea, Vontobel, Sophie, Fischer, Stefan, Kappler, Andreas, Kretzschmar, Ruben
Format: Article in Journal/Newspaper
Language:English
Published: ETH Zurich 2022
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Online Access:https://dx.doi.org/10.3929/ethz-b-000529133
http://hdl.handle.net/20.500.11850/529133
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Summary:In freshwater wetlands, redox interfaces characterized by circumneutral pH, steep gradients in O2, and a continual supply of Fe(II) form ecological niches favorable to microaerophilic iron(II) oxidizing bacteria (FeOB) and the formation of flocs; associations of (a)biotic mineral phases, microorganisms, and (microbially-derived) organic matter. On the volcanic island of Iceland, wetlands are replenished with Fe-rich surface-, ground- and springwater. Combined with extensive drainage of lowland wetlands, which forms artificial redox gradients, accumulations of bright orange (a)biotically-derived Fe-rich flocs are common features of Icelandic wetlands. These loosely consolidated flocs are easily mobilized, and, considering the proximity of Iceland's lowland wetlands to the coast, are likely to contribute to the suspended sediment load transported to coastal waters. To date, however, little is known regarding (Fe) mineral and elemental composition of the flocs. In this study, flocs from wetlands (n = 16) across ... : Science of The Total Environment, 816 ...