Contemporary Surface Processes and Landscape Change

Abstract

Contemporary, as opposed to palaeo- (past) processes are those Earth surface processes currently active in modifying South Africa’s physical (geological, geomorphological, pedological) environment. These processes provide the energy to perform the work necessary to alter the morphology of landforms and landscapes. External (surface) or exogenic processes are the manifestation of a number of agents of weathering and erosion. In this context, erosion refers to the removal and transportation of weathered rock material, unconsolidated sediment and soil. Ultimately, such material is laid down elsewhere via deposition of the transported material. In this way, landforms change over time. Contemporary landforms found in South Africa are usually a product of both past and present processes. In addition, landforms may be products of erosion, or deposition, or a combination of the two. In this chapter, our current understanding of the role of weathering (a static process, which is distinguished from erosion), important agents of erosion, namely running water (fluvial), wind (aeolian), and the sea, is reviewed. This is done in the context of the most recent research into contemporary surface processes and landscape changes in South Africa. The impacts of humans on contemporary processes, and vice versa, are also considered.