Mineral degradation

Landmine signature chemicals change form, chemical properties, and eventually become eliminated from soil systems by microbiological and soil mineral degradation reactions. 

Aerobic mineral oxidation resulting in mineral degradation and product mobilization Aerobic bacterial oxidation of elemental sulphur (S°), of various mineral sulphides such as pyrite (FeS2), chalcopyrite (CuFeS2), arsenopyrite (FeAsS), sphalerite (ZnS), cobalt sulphide (CoS) and nickel sulphide (NiS) to corresponding metal sulphates, and of uraninite (UO2) to U02 are examples in which oxidizable minerals undergo dissolution of one or more of their constituents, which are thus mobilized (see Ehrlich, 2002a). 

Microbial populations associated with sulfide mineral degradation. 371... 

MICROBIAL POPULATIONS ASSOCIATED WITH SULFIDE MINERAL DEGRADATION... 

Principal sulfur-oxidizing and iron-oxidizing bacteria involved in sulfide mineral degradation... 

Baker, W.E., 1973. The role of humic acids from Tasmanian podzolic soils in mineral degradation and metal mobilization. Geochim. Cosmochim. Acta, 37 269—281. 

Baker, W. E. (1973). Role of humic acids from Tasmanian podzolic soils in mineral degradation and metal mobilization. Geochim. Cosmochim. Acta 37, 269-281. Bamhisel, R. I. (1977). Chlorites and hydroxy interlayered vermiculite and smectite. In "Minerals in Soil Environments" (J. B. Dixon and S. B. Weed, eds.), pp. 331-356. Soil Science Society of America, Madison, Wisconsin. 

Nitrogen fixation, denitrification, soil weathering, phosphate fixation, clay mineral degradation, and potassium and transition metal fixation are problems for which the reaction rates are usually as, or more, important than equilibrium. Most soil chemical applications of kinetics have been in soil microbiology and soil biochemistry, where the lack of equilibrium is more obvious. The use of kinetics in inorganic soil chemistry will undoubtedly broaden in the future. It can even be argued that kinetics is basic to thermodynamics, because equilibrium is the condition where opposing reaction rates are equal. 

Figure 5 Characters of the clay mineral degradation in Quaternary sapropels of the eastern Mediterranean basins.

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