Invasive alien plants have a negative impact on ecosystem goods and services derived from ecosystems.
Consequently, the aggressive spread of invasive alien plants (IAPs) in the river catchments of South Africa
is a major threat to, inter alia, water security. The Olifants River catchment is one such a catchment that is
under pressure because of the high demand for water from mainly industrial sources and unsustainable
land-use, which includes IAPs. This study considered the cost-effectiveness of clearing IAPs and compared
these with the cost of a recently constructed dam. The methods used for data collection were semistructured
interviews, site observation, desktop data analysis, and a literature review to assess the impact of
IAPs on the catchment’s water supply. The outcomes of this study indicate that clearing invasive alien plants
is a cost-effective intervention with a Unit Reference Value (URV) of R1.44/m3, which compares very
favourably with that of the De Hoop dam, the URV for which is R2.93/m3. These results suggest that
clearing invasive alien plants is a cost-effective way of catchment management, as the opportunity cost of
not doing so (forfeiting water to the value of R2.93/m3) is higher than that of protecting the investment in the
Pretorius, Simone Norah(University of Pretoria, 2017)
The Mzimvubu River is the largest river in South Africa without a dam. The Department of Water and Sanitation has identified the Tsitsa River Catchment on the Mzimvubu River as a potential site for a water resource ...
Schwirzer, Anna-Maria(University of Pretoria, 2008-04-24)
Wetlands within South Africa are an important source of water and nutrients necessary for biological productivity and often the survival of the local people. In a country where the rural communities depend on wetlands for ...
Sanga, Gody Jonathan(University of Pretoria, 2017)
This study uses the Uluguru water catchments in Tanzania to assess whether marketbased
policy instruments can secure internalisation of externalities in such complex
socio-economic-ecological systems which are not only ...