Wetlands

Many of the adverse impacts of human activities on biodiversity manifest themselves most strongly in the wetlands of South Africa. In terms of the Convention on Wetlands of International Importance especially as Waterfowl Habitat (Ramsar Convention) these include "areas of marsh, fen, peatland or water, whether natural or artificial permanent or temporary, with water that is static or flowing, fresh, brackish or salty, including areas of marine water the depth of which does not exceed six metres". Wetlands include riverine, lake, mash, estuarine, and marine systems. Wetlands play a crucial role in terms of providing clean water, maintaining biodiversity, protecting areas against floods, recharging aquifers, buffering against toxins, and providing areas for recreation, education and research.

Although there is a lack of information concerning wetland losses in South Africa, the evidence which does exist, suggests clearly that the loss of wetlands has been high, with loss appearing to be greatest in the coastal and inland margin zones of the country. In the Mfolozi catchment, for example, some 58 % of the original wetland area is estimated to have been lost.

Freshwater systems

Adverse impacts on freshwater systems are of critical concern given both the scarcity of and increased demand for water in the region. The flow of almost every river system has been regulated by storage dams, or by structures associated with the inter-basin transfer of water. Stalinization, eutrophication, and pollution by heavy metals, mine dump effluents, pesticides, insecticides and herbicides have considerably reduced both surface- and ground water quality. Catchment changes through afforestation, alien plant invasion, irrigation and over-abstraction, and human settlement have reduced natural run-off and groundwater levels substantially, and invasive plants and animals jeopardize indigenous wildlife on a national scale. Moreover, wetlands such as mashes, bogs and floodplains have undergone considerable alteration and degradation: through drainage for crop and timber cultivation; infilling for urban and industrial development and waste disposal mining for the extraction of sand, clay and peat; as well as through a range of other activities.

Estuary

Estuarine areas, as the interface between rivers and the sea, include some of the most productive and threatened ecosystems in South Africa.

The ecological functioning of estuarine ecosystems is critically dependent upon the complex and dynamic interplay between rivers and the sea. Activities having far-reaching effects on estuarine ecosystems include excessive water abstraction, resulting in a reduction of freshwater to estuaries; agricultural practices that lead to increased soil erosion and thus silt deposition in estuaries; urban or industrial development adjacent to estuaries; modifications to river and tidal flows through floodplain development and the construction of bridges, harbors, and dams; and pollution resulting from the diversity of activities occurring in catchments.

Marine and coastal areas

Several processes are currently underway which support the careful and effective management of South Africa's marine and coastal areas, including the development of national policies on coastal zone management, and on marine fisheries. It is necessary to adopt a cross-sectoral approach if marine biodiversity is to be conserved effectively and used sustainably. The entire hydrological cycle must be treated as an integrated unit.

Government, in collaboration with interested and affected parties, will:

1. Ensure that considerations relating to the conservation and sustainable use of marine and coastal biodiversity are effectively incorporated into national policies on integrated pollution control and marine fisheries; and support the rapid development of a national policy on coastal zone management, and the incorporation of biodiversity considerations therein.
2. Require that those using marine resources, receiving services from marine and coastal ecosystems, or producing waste must bear all environmental, social, and economic costs, and the responsibility for any consequential detriment to the environment and to associated biota.
3. Prevent inappropriate activities and development along the coast, and that of linear or ribbon development in particular. Ensure that adequate buffer strips are retained to protect the coastal zone.
4. Amend existing legislation or introduce new legislation to control the exploitation of all marine organisms that are not presently legally protected.
5. Investigate the impacts of commercial fishery practices on ecosystems, on target, non-target and by-catch species, on the viability of populations, and on genetic diversity.
6. Determine the impact of recreational fishers on fisheries, fish and their habitats, and develop a national strategy and guidelines for managing recreational fishing on an ecologically sustainable basis.
7. Undertake research concerning the management and control of subsistence artisanal fisheries, including the development of appropriate monitoring systems.
8. Determine the impact of mariculture species and management practices on biodiversity, and develop appropriate guidelines for mariculture developments.
9. Develop and promote fishing techniques and procedures that are species and size specific, and that have the least impact on ecosystems and on non-target species.