An overview of pedogenesis in Technosols in South Africa^§

^§§ This article is based on a paper presented at the 5th International Soil Classification Congress, 5–7 December 2016, Bloemfontein, South Africa

Abstract

Technosols are soils dominant in technical artifacts, formed from anthropogenic deposits or transported materials. While anthropogenic in origin, it is clear that pedogenic processes are active within Technosols, i.e. transformation and translocation of elements, minerals and particles within these materials. Three different Technosols were assessed as part of this study, comprising gold, platinum and kimberlite Technosols. The objective of this paper was to discuss the pedogenic processes observed within the three Technosols. The discussion is based on observations of different pedogenic processes within the Technosols as well as analytical data and published data from the literature. Irrespective of the time since deposition or rehabilitation, well-defined pedochemical transformation processes, such as changes in pH and cation exchange capacity and base saturation, have been observed within these Technosols and are referenced within this article. Additional pedogenic processes, including leaching, eluviation–illuviation and oxidation, as well as normal weathering are also present. Finally, field observations revealed processes such as salinisation, neo-mineralisation, surface crusting and horizon differentiation in terms of structural differences have been observed within the Technosols studied. Structural differences resulted in horizon differentiation due to the addition of compost and the establishment of vegetation in a portion of the Technosols.

Keywords:

• pedochemical transformation
• pedogenic processes
• Technosols
• transformation
• translocation

Notes

^§ § This article is based on a paper presented at the 5th International Soil Classification Congress, 5–7 December 2016, Bloemfontein, South Africa