Mercury global metal cycling

Volatilization is also a dominant transport mode for mercury, which is the most volatile metal in its elemental state. As with lead, a key reaction that can increase the volatility of mercury is formation of an organometallic compound. In this case, the reactions take place in water and are primarily biological, being mediated by bacteria commonly found in the upper levels of sediments. These reactions and their importance in the global mercury cycle are discussed in some detail later in the chapter. 

In this final section, the global cycles of two metals, mercury and copper, are reviewed. These metals were chosen because their geochemical cycles have been studied extensively, and their chemical reactions exemplify the full gamut of reactions described earlier. In addition, the chemical forms of the two metals are sufficiently different from one another that they behave differently with respect to dominant... 

In this final section, the global cycles of two metals, mercury and copper, are reviewed. These metals... 

The global cycling of copper has been reviewed by Nriagu (1979) and is described schematically in Fig. 15-16. Like most heavy metals and in contrast to mercury, the flux of copper from terrestrial to oceanic reservoirs is dominated by transport in rivers. Copper reaching the oceans by atmospheric transport is of the same order of magnitude as that by three strictly anthropogenic sources direct discharge... 

SuKHENKO SA and Vasiliev OP (1996) A Re onal Mercury Budget for Siberia and the Role of the Region in Global Cycling of the Metal. I n Baeyens W, Ebinghaus R and Vasiliev O, eds, Global and Regional Mercury Cycles Sources, Pluxes and Mass Balances, pp. 123-133. Kluwer Academic Publishers, Dordrecht, Netherlands and Norwell, MA, USA. 

Though mercury (Hg) occurs naturally in the environment, anthropogenic activities have affected its global cycle in ways that mobiUze increasing amounts of this metal currently, such human-related activities mobilize more Hg than do natural... 

---