scor

FacebookTwitter

Total mercury (THg), methylated mercury (MeHg), and dissolved gaseous mercury (DGM) concentrations were determined along 40°S in the Atlantic Ocean. All Hg species had higher concentrations in western than in eastern basin, although they are at the ultra-low femtomolar level.

MeHg increases with lower oxygen concentration, substantiating that microbial respiration of organic matter stimulates MeHg formation. Sediment is generally a likely source of MeHg to the water column; however it stays a modest contributor in this ocean region. At the surface, photo-demethylation might be responsible of the low MeHg concentration.

DMeHg was measured only at one station. As expected, it was higher in the intermediate and deep waters below 1000m and very low above them, especially in the surface waters. It reached its highest concentration in the Upper Circumpolar Deep Water (UCDW), similarly to DGM, probably due to lower oxygen concentrations and hence lower oxidation potential.

Altogether, results show very dynamic Hg processes in this ocean region, which are of global importance for Hg cycling.

16 Bratkic l
Figure:
The figure shows total mercury (THg), monomethyl mercury (MeHg) and dissolved gaseous mercury (DGM) concentrations in the water column. Mercury is ubiquitous (THg), DGM is stratified, which means that different water masses have different DGM concentrations, and MeHg is very low, but is sometimes higher in regions with plenty of chlorophyll. Blank spaces show areas, where the concentrations are too low to be reliably measured. DGM is lowest at surface, indicating that it escapes from water to the atmosphere. Click here to view the figure larger.

Reference:

Bratkič, A., Vahčič, M., Kotnik, J., Obu Vazner, K., Begu, E., Woodward, E. M. S., & Horvat, M. (2016). Mercury presence and speciation in the South Atlantic Ocean along the 40°S transect. Global Biogeochemical Cycles, 30(2), 105–119. doi:10.1002/2015GB005275

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)

eGEOTRACES Atlas

 Data Assembly Centre (GDAC)

 Outreach

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.