Anthropogeomorphological Wetlands in South Africa

The influence of humans on the environment is becoming more pronounced with increase in, particularly, urban population. The imprint humans leave behind is so pronounced that a new geological epoch, the Anthropocene, has been created to accommodate the effects of direct and indirect anthropogenic influences. Anthropogeomorphology is the study of how humans modify and create landforms and landform processes. Humans deliberately change the distribution of water resources, modifying flow patterns, damming, draining areas retaining water and extracting underground water sources such as manipulation of fluvial environments by constructing structures to alter their hydrology – historically, from ancient aqueducts to modern hydraulic and civil engineering.
Wetland type and functioning result from driving forces such as geomorphology, hydrology and biological processes (e.g., colonization, competition, decomposition). The hydrology of wetlands in semi-arid interior regions of southern Africa where evapotranspiration exceeds precipitation is often dependant on catchment surface water flows, sustained groundwater and hillslope intermediate flows which is reflected in vegetation diversity and often mirrors the transformation of a catchment. Wetlands are generally seen as natural geomorphological features but can be both formed and modified due to human activities, therefore the subject of anthropogeomorphology. These activities can be both direct, restoration projects for example, and/or indirect in nature. Indirect drivers of anthropogeomorphological wetlands are broad and not properly documented and can range from consequences of urbanisation to agricultural irrigation runoff.
The aim of this research is to investigate the role of anthropogenic wetland formation in the realm of anthropogeomorphology in South Africa and to assess their distribution and current standing in wetland classification systems. Methods include categorizing anthropogeomorphological wetlands identified by comparing land-use, development, and vegetation cover changes by using GIS. The characteristics of these sites are further analysed based on category and compared to the characteristics of natural wetlands in its vicinity.

Keywords: Wetlands, geomorphology, anthropogeomorphology