Historical records of mercury in southern latitudes over 1600 years: Lake Futalaufquen, Northern Patagonia

Authors
Daga, Romina Betiana; Ribeiro, Sergio; Pavlin, Majda; Rizzo, Andrea Paula; Lojen, Sonja; Vreca, Polona; Horvat, Milena; Arribere, Maria Angelica
Publication Year
2016
Language
English
Format
article
Status
Published version
Description
Mercury is released to the environment from natural and anthropogenic sources, and through atmospheric transport is distributed globally. Lake Futalaufquen (42.8°S) is an oligotrophic lake located in Los Alerces National Park (Northern Patagonia), providing a remote and unpolluted study system. A lacustrine sedimentary sequence revealed 1600 years of Hg deposition, identifying natural baselines and marked peaks not correlated with long-range atmospheric transport. Organic matter and catchment erosion were discarded as Hg drivers. Natural background, pre-1300 CE Hg concentrations, ranged between 27 and 47 ng g-1 (accumulation rates from 8 to 15 μg m-2 y-1). From 1300 CE on, the Hg background profile did not follow the generally increasing Hg pattern observed in both Southern and Northern Hemisphere since pre-industrial times. It was not until the last century that a 1.6-fold increase is observed in the Hg accumulation rate, considered among the lowest increments in southern South America. Noteworthy local/regional sources of Hg for this area, along with global transport, are forest fires and volcanic activity. Between approx. 1340 and 1510 CE, sharp increase in Hg concentration and accumulation rate (up to 204 ng g-1 and 51 μg m-2 y-1, respectively) were clearly associated with extended fire episodes. Furthermore, high Hg peaks during the last 300 years were associated with volcanic eruptions in northernmost Patagonia together with fairly irregular fire episodes, caused by anthropogenic burning by settling population in the Andes.
Fil: Daga, Romina Betiana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina
Fil: Ribeiro, Sergio. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina
Fil: Pavlin, Majda. Jožef Stefan Institute; Eslovenia
Fil: Rizzo, Andrea Paula. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina
Fil: Lojen, Sonja. Jožef Stefan Institute; Eslovenia. University of Nova Gorica; Eslovenia
Fil: Vreca, Polona. Jožef Stefan Institute; Eslovenia
Fil: Horvat, Milena. Jožef Stefan Institute; Eslovenia
Fil: Arribere, Maria Angelica. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina
Subject
ARGENTINA
ATMOSPHERIC DEPOSITION
FIRES
GLOBAL POLLUTANT
LAKES
VOLCANISM
Meteorología y Ciencias Atmosféricas
Ciencias de la Tierra y relacionadas con el Medio Ambiente
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/61876