title: Anthropogenic mercury signals in lake sediments from southernmost Patagonia, Chile.
abstract: Atmospheric mercury fluxes to terrestrial and aquatic surfaces in the Northern Hemisphere have increased since the Industrial Revolution. However fluxes are not well characterized for the Southern Hemisphere, since environmental archives are comparatively scarce. Mercury records from (210)Pb-dated sediment cores of three South Patagonian lakes were investigated in order to reveal the influence of anthropogenic activities on atmospheric mercury deposition in remote lakes of the Southern Hemisphere. Comparison with indicators of organic matter sources (carbon and nitrogen/carbon ratios) and a conservative mineral soil element (zirconium) in the sediments revealed that soil erosion is an important process contributing mercury to these lakes and influenced variation in concentrations through time. However, at ~1900 AD mercury accumulation increased independent from soil erosion and peaked from 1980 to 2000 AD. We attribute this to an increase in atmospheric mercury deposition in this remote region of the Southern Hemisphere. Mean flux ratios, which reflect the increase in modern mercury accumulation compared to pre-1850 AD, lie within a range of 1.4 to 2.4. These values indicate an increase in atmospheric mercury deposition slightly lower than predictions derived from global mercury models that suggest an increase in Hg deposition by a factor of 2 to 3.
authors: Institut für Geoökologie, Abteilung Geochemie, Technische Universität Braunschweig, Langer Kamp 19c, 38106 Braunschweig, Germany. y-m.hermanns@tu-bs.de
authors: Yvonne-Marie
authors: YM
authors: Hermanns
authors: Harald
authors: H
authors: Biester
mesh_terms: D002677:Chile; D004787:Environmental Pollution / Q000266:history; D019015:Geologic Sediments / Q000737:chemistry*; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D060106:Lakes / Q000737:chemistry*; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D008962:Models, Theoretical; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D060753:Water Quality
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury