Abstract
The apparent activation energy (Ea) is an important parameter in improving our understanding of the processes controlling the emission of mercury from soils. We have investigated the effect of major environmental variables on mercury emission fluxes (MEFs) and on the determination of the apparent activation energy for the emission of mercury from soils (Ea-FHg). Our results show that Ea-FHg can be expressed as a function of soil texture and total mercury concentration in the soils and will generally increase with increasing clay fraction and decreasing total Hg-concentration in soils. The observed behaviour is in agreement with the Freundlich Adsorption Hypothesis and thus strongly indicate that MEFs over soils are driven by the interfacial equilibrium of Hg° between soil matrix and soil air.