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GeoJournal

, Volume 23, Issue 1, pp 41–48 | Cite as

Soil erosion on a sub-tropical coastal dune complex, Transkei, Southern Africa

  • Hanvey Patricia M. 
  • Dardis George F. 
  • Beckedahl Heinrich R. 
Soil Erosion and Host Materials in Africa

Abstract

A fossil dune complex on the east coast of southern Africa is presently undergoing extensive accelerated erosion, with concomitant dune reactivation and degradation, unconfined erosion (sheetwash and wind deflation) and extensive development of V-shaped, ravine-type gully forms on hillslopes composed of thick sequences of Quaternary (Berea Formation?) dune sands. The sands comprise a thick, reddened, ferralitic sand carapace overlying white, poorly cemented quartzitic sands. Soil erosion has resulted from degradation of the red dune sand cover. Despite the cohesionless nature of the host materials, gully forms developed on dune sands are typologically similar to those developed in regolith or soft bedrock. This demonstrates that gully forms are influenced by the degree of homogeneity, rather than the absolute strength, of the host material subject to erosion. Factors which have contributed to erosion are discussed.

Keywords

Environmental Management Soil Erosion East Coast Dune Sand Host Material 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1991

Authors and Affiliations

  • Hanvey Patricia M. 
    • 1
  • Dardis George F. 
    • 2
  • Beckedahl Heinrich R. 
    • 3
  1. 1.Department of Geography and Environmental StudiesUniversity of the WitwatersrandJohannesburgSouth Africa
  2. 2.Sedimentology and Palaeobiology LaboratoryAHECCambridgeUK
  3. 3.Department of GeographyUniversity of TranskeiTranskeiSouthern Africa

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