Soluble manganese(III) [Mn(III)] is a phase traditionally considered non important in aqueous redox reactions. However, applying a spectrophotometric method sensitive to Mn oxidation state, Madison and co-authors found that up 90% of the Mn in porewater collected from sediment cores in the St. Lawrence Estuary is soluble Mn(III). The authors conclude that the conceptual model of the sedimentary redox cycle should be reviewed to include dissolved Mn(III). This result also has implication for the oxidation of iron(II) [Fe(II)] to Fe(III) process and, because Mn(III) can act as either an electron acceptor or an electron donor, the authors suggest that reduction-oxidation capacity of the soluble Mn pool in sediments has been underestimated.

13 Madison l
Figure: This figure shows the study sites (on the top), a picture of a core (on the left) and Mn and Fe profiles
Picture © George W. Luther III. Please click here to view the figure larger

Mn(III) can also form when MnO2 oxidizes Fe(II) to Fe(III). Figure A shows the solid phase data; Figure B the soluble Fe data; Figure C the soluble Mn data; in Figure D, a diagenetic model was used to profile the data. The agreement is good as various reactions for the production and loss of Mn(III) were added to the model. Models can finally predict the position and shape of all soluble Mn species.


Madison, Andrew S., Bradley M. Tebo, Alfonso Mucci, Bjørn Sundby, and George W. Luther III (2013) Abundant Porewater Mn(III) is a Major Component of the Sedimentary Redox System, Science 23 August 2013: 341 (6148), 875-878. DOI:10.1126/science.1241396

Filter by Keyword

Aerosol Inputs Aerosols Aluminium Analysis Anoxia Antarctic Geology Arctic Ocean Arsenic Artificial Intelligence Atlantic Ocean Atmospheric Dynamic Barium Barium Isotopes Behavior Benthic Beryllium BioGEOSCAPES Biological Pump Black Sea Boundary Exchange Boundary Scavenging Budget Cadmium Cadmium Isotopes Cadmium Sulfide Chromium Chronium Isotopes Circulation Climate Change CO2 Degassing Coastal Area Cobalt Copper Copper Isotopes Cycles Data Compilation Deep Water Dissolved Concentrations Distribution Distribution Coefficient Ecosystem Eddy Kinetic Energy Environmental Change Estuaries Experiments Export Fluxes Fate Fertilisation Fractionation Gadolinium Gallium Global Scale Hafnium Hafnium Isotopes Helium Helium Isotopes Hydrothermal Hypoxia Ice ICPMS Indian Ocean Inputs Intercalibration Intercomparison International Polar Year Iodine Iron Iron Isotopes Iron Sulfide Isotopes Land Ocean Inputs Lanthanum Lead Lead Isotopes Limitation Lithogenic Macronutriments Mammals Manganese Mediterranean Sea Mercury Mesopelagic Mesoscale Transport Methylmercury Microbial Micronutriments Modelling Multiple TEIs Neodymium Neodymium Isotopes Nepheloids Nickel Nitrate Nitrogen Nutrients Organic Matter Osmium Oxygen Pacific Ocean Paleoceanography Paleocirculation Particle Fluxes Particles Particulate Organic Carbon Phosphate Phosporus Phytoplankton Pitzer Equations Precipitation Procedure Processes Productivity Protactinium Protocol Proxy Radium Radium Isotopes Rare Earth Elements Red Sea Remineralization Residence Times River SAFE Samples Scandium Scavenging Sea Ice Sediments Shelf Silicon Silicon Isotopes Southern Ocean Speciation Submarine Ground Water Discharge Surface Waters Thorium Thorium Isotopes Thorium-Protactinium Time Series Total Hg Transmissiometer Uranium Uranium Isotopes Yttrium Zinc Zinc Isotopes

 Data Product (IDP2017)


 Data Assembly Centre (GDAC)


Subscribe Mailing list

Contact us

To get a username and password, please contact the GEOTRACES IPO.

This site uses cookies to offer you a better browsing experience. Find out more on how we use cookies and how you can change your settings.