The RESILIM-Olifants program focuses specifically on the transboundary Olifants River Catchment which forms part of the even-wider Limpopo River Basin. The Olifants River Catchment, or ORC, is of particular concern because of the wide-scale threats to biodiversity and the ecosystem services that support peoples’ livelihoods. Much of our work in Phase I focused on a basin-wide assessment which is summarized below as background to the project-specific work.
From both an aquatic and terrestrial perspective the Olifants River Catchment is a rich and diverse landscape. It is home to areas of endemism and high biodiversity, particularly along the Drakensberg Escarpment which includes the Blyde and Legalameetse Nature Reserves and some tributaries of the Olifants. The Olifants River flows into the Limpopo River and the Maputoland-Tongoland Ecoregion, an area of rich biodiversity and endemism which includes the Limpopo River estuary. Currently, the Olifants River is the only tributary that sustains flows of the Limpopo River in the dry season.
A changing landscape
In 2005 the Olifants River ceased flowing for a number of days in 2005, prompting widespread concern and calls for an integrated focus on all of the easterly-flowing rivers of the Lowveld of South Africa. Despite the enabling legislative framework for water reform in South Africa introduced in 1998, most rivers in this catchment continue to degrade in both quality and quantity.
Given that these rivers form part of international systems, the implications are of wider significance than for South Africa alone. Indeed, the Olifants Catchment is a particular concern given that it is the largest contributor of flows to the transboundary Limpopo River. We estimate that flows into Mozambique support the livelihoods of between 6000 and 10 000 small-scale farmers and the critical mangroves of the Zongoene estuary which experiences saltwater intrusion and salinization due to reduced flows and declining mangroves.
Large areas of the Catchment have been substantially modified and the upper catchment is almost totally transformed through agriculture and mining with the latter increasing significantly in the last decade even across former agricultural areas (link Figure below)). A number of ecosystems are considered either critically endangered or endangered and many more are vulnerable. In Mozambique, the estuarine area is classified as a National Maritime Ecosystem Priority area. Although there are substantial areas of natural landcover especially in the Lowveld along the escarpment and Blyde River Catchments many of these are also threatened by a range of drivers including mining, urbanization, afforestation and invasive alien plants. Despite the wide range of habitat types in the grassland and savanna biomes climate change is likely to see a major transformation of the already threatened grasslands to savannas.
Equally, the mainstem of the Olifants River is regarded as critically endangered from its source to the protected areas in the Lowveld. Water quality is a major issue for the catchment. Declining water quality and decreased flows threaten aquatic systems along the entire Olifants River within South Africa and to the Xai Xai estuary in Mozambique. Almost all westerly-flowing rivers in the high and middle-veld are critically endangered. Intact river systems are limited to the Blyde and some tributaries of the Steelpoort and the lower Olifants.
With over 600 former or existing mines (coal and platinum in particular), impacts are felt in both the terrestrial and aquatic systems and on human livelihoods. The discharge effluent from many of the 100 plus waste-water treatment works (public and private: AWARD data), many of which are struggling to meet national standards, impacts on the aquatic systems downstream and again on peoples’ livelihoods.
Indeed AWARD’s work suggests that the most vulnerable livelihoods in terms of the direct dependencies on ecosystem services are in the former homelands which cover about half of the ORC. AWARD has identified a number of integrated biodiversity areas which track the mainstem Olifants River (after Loskop Dam) and include the Steelpoort and Blyde Catchment and the swathe of land across the escarpment into the Lowveld (Figure 1). Key elements contributing to the selection of these areas include exceptionally high values of diversity at multiple levels of biodiversity, high levels of endemism, the presence of threatened ecosystems, larger contiguous areas of intact habitats, and under-protected habitat types.