ISSN:
1573-2932
Keywords:
atmospheric pollution
;
bloedite
;
evaporites
;
fog impaction
;
soils
;
thenardite
;
vegetation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
Notes:
Abstract White efflorescences, representing evaporites that coat stubble grass vegetation, were observed in September 1991 on a farm in the Ermelo area, Mpumalanga highveld of the Republic of South Africa. Occurrences were in irregular patches. Investigation of the evaporites by means of X-ray diffraction, differential thermal analysis, scanning electron microscopy with EDX, and chemical analyses revealed the following minerals, presented in order of decreasing abundance: thenardite, bloedite, gypsum and kieserite. Accumulation of the salts, which are highly water soluble, probably occurred during the six dry winter months, suggesting a deposition rate of up to 11–15 g of thenardite m-2 yr-1. It is proposed that the efflorescences had formed by fog impaction on grass blades. They are, to the authors' knowledge, the first recorded evaporite deposits formed by atmospheric deposition.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1005033430238
Permalink