4.3.3 Harvesting of natural resources: 

Commercial fishing supplies international markets and markets in the more affluent (urban) areas of the country. Many rural coastal communities depend on the use of resources for their subsistence, and artisanal harvesting of resources is practised as a means to supplement household income.

South Africa's estuaries are extensively used for both subsistence and recreational fishing and bait collection. Unsustainable levels of exploitation threaten the ecological integrity of estuarine systems, particularly where a few species are targeted for harvesting.

Indicators for sustainable resource use, at subsistence, artisanal and commercial levels of exploitation, have yet to be determined. Quota systems and other measures have been introduced to maintain sufficient stocks of popular commercial species, for example abalone and rock lobster. However, so far these have failed to achieve their purpose of sustainable resource management.

4.3.4 Land use change:  

Urban encroachment into the coastal zone and the resultant change in coastal land use creates various environmental pressures on the landscape and habitat transformation. Urbanization around estuaries cuts the estuary off from the surrounding terrestrial habitats and the bio-physical processes which link the two systems together. Estuarine ecosystems are exposed to the risk of water quality deterioration and eutrophication, particularly in the case of seasonally closed systems, because of sewage discharge and the introduction of stormwater and other effluents. Deterioration in marine water quality also presents human health risks.

The success of the government's Spatial Development Initiatives (SDIs) is dependent on the expansion of one or more of South Africa's major ports. For example, the Kwa-Zulu Natal SDI and associated (Industrial) Development Zone is closely linked to expansion of the Ports of Richards Bay and Durban. Similarly, the West Coast Investment Initiative and associated (Industrial) Development Zone is closely linked to expansion of the Port of Saldanha, while the Coega Industrial Development Zone is closely linked to the construction of the proposed Ngqura port, near Port Elizabeth. Such development will increase pressure on the coastal and marine systems and resources as a result of increased demand for land and freshwater for domestic and industrial use. It is such pressures that pose risks to human health and to the sense of place for communities.

Port related developments also give rise to particular environmental pressures on the coastal and marine environment. These include the destruction of benthic habitat as a result of dredging operations. The waste material from these operations smother the organisms on the sea floor and sometimes contains trace metals and other pollutants. In 1991 the volumes of spoil originating from dredging operations (maintenance and reclamation) were estimated to be 3.7 million cubic metres/year.

Environmental pressures are more typically linked to the cumulative effects of diverse types of risks arising from coastal development, recreation activities, pollution, and consumptive exploitation of resources.

Marine and coastal pollution is monitored using criteria such as: bacterial contamination of water where beneficial water uses might be affected (e.g. bathing); mussel watch programmes, where levels of chemical contaminants in biological tissue are monitored; and monitoring of the status of benthic communities in the vicinity of marine outfalls, intertidal rocky shore communities and meiofauna of sandy beaches.

Figure 4.10 Isogram depicting classification of the surf-zone at 28 sampling stations.

Figure 4.10 depicts the classification of the surf-zone at sampling stations located in and around the Durban beachfront. The classification system used in the monitoring is based on international standards, but simplified into four classes. Class I is regarded as excellent by all international standards, while classes III and IV indicate very significant contamination from land-based sources. Thus the effect of the harbour discharges on surf-zone water quality up to 1969 is obvious. After commissioning the two submarine outfalls in 1969, bathing water quality on Durban's beaches improved markedly, but the influence of the Umgeni River (Station 1) and the Umlaas River and Reunion Canal complex (Stations 20 and 23 respectively) continued. The short-term impact of the 1987 floods is also evident. Recent efforts at improving sewage reticulation and treatment in the Umlaas catchment appear to have achieved some improvement since 1996.

Almost all of South Africa's estuaries have been altered from their original state. The number and relative condition of estuaries of different sizes is described in Table 4.2 below. Reduced freshwater inflow due to water extraction for human usage is a major factor which has caused this change. Most of the larger estuaries have some degree of built environment along the shoreline. Marina developments have also contributed to the alteration of some estuaries, e.g. Great Berg, Kowie and Kromme estuaries.

>     Marine and Coastal Systems: State

There is also information about Terrestrial Ecosystems in the following reports:
Metropolitan reports:
	Cape Metropolitan Council (1998 edition)		Durban Pilot Study
	Greater Johannesburg Metropolitan Council (1999 edition)		Greater Pretoria Metropolitan Council (1999 edition)