Assessing the potential for re-emission of mercury deposited in precipitation from arid soils using a stable isotope.

A solution containing 198Hg in the form of HgCl2 was added to a 4 m2 area of desert soils in Nevada, and soil Hg fluxes were measured using three dynamic flux chambers. There was an immediate release of 198Hg after it was applied, and then emissions decreased exponentially. Within the first 6 h after the isotope was added to the soil, approximately 12 ng m(-2) of 198Hg was emitted to the atmosphere, followed by a relatively steady flux of the isotope at 0.