Methylmercury production in the water column of an ultraoligotrophic lake of Northern Patagonia, Argentina

RIBEIRO GUEVARA, SERGIO; QUEIMALIÑOS, CP; DIÉGUEZ, M.C.; ARRIBÉRE, M.

CHEMOSPHERE

Elsevier

Lugar: Oxford; Año: 2008 vol. 72 p. 578 - 585

0045-6535

Methyl-mercury (CH3Hg+) production was studied in freshwaters from lake Moreno, an ultraoligotrophic system belonging to Northern Patagonia. Hg2+ labelled with high specific activity 197Hg was spiked to water samples in concentrations of 10 ng l1, and incubated in laboratory for 3 d time trends under different conditions. Experimental water was sampled daily to evaluate CH3 197Hg+ production. Lake water used in the experiments was sampled just below the upper limit of the metalimnion (30 m depth), where maximum values of chlorophyll a have been measured previously. Sampling was performed in late autumn, when the plankton fraction