Articles | Volume 20, issue 14
https://doi.org/10.5194/bg-20-2883-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-20-2883-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
20 Jul 2023
Research article |
| 20 Jul 2023
| 20 Jul 2023
Estuarine flocculation dynamics of organic carbon and metals from boreal acid sulfate soils
Joonas J. Virtasalo
CORRESPONDING AUTHOR
Marine Geology, Geological Survey of Finland (GTK), 02150 Espoo, Finland
Peter Österholm
Department of Geology and Mineralogy, Åbo Akademi University, 20500 Turku, Finland
Eero Asmala
CORRESPONDING AUTHOR
Environmental Geochemistry, Geological Survey of Finland (GTK), 02150 Espoo, Finland
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Short summary
We mixed acidic metal-rich river water from acid sulfate soils and seawater in the laboratory to study the flocculation of dissolved metals and organic matter in estuaries. Al and Fe flocculated already at a salinity of 0–2 to large organic flocs (>80 µm size). Precipitation of Al and Fe hydroxide flocculi (median size 11 µm) began when pH exceeded ca. 5.5. Mn transferred weakly to Mn hydroxides and Co to the flocs. Up to 50 % of Cu was associated with the flocs, irrespective of seawater mixing.
We mixed acidic metal-rich river water from acid sulfate soils and seawater in the laboratory to...
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