How does one define a wetland?
Why are wetlands protected?
What legislation is in place to safeguard these systems?
Many definitions of a “wetland” have been put forward by numerous authors but there is no one definition that has achieved global acceptance. This is related to the fact that wetlands exhibit enormous diversity according to their genesis, geographical location, water regime and chemistry, dominant plants and soil and sediment characteristics. For this reason classification of wetland types is also fraught with difficulty. A commonly cited definition of “wetland” is by Crites et al., 1995.
They define ‘wetlands’ as being areas of ‘land where the water surface is near the ground surface for long enough each year to maintain saturated soil conditions, along with the related vegetation’. In most definitions, however, the “presence” of semi-permanent water is a central theme. Cowardin et al., (1979) suggest that water determines the soil, vegetation and organism characteristics found within the wetland system, thus for an area to be defined as a wetland there must be surface water or saturated soil continuously or at least for much of the year. “Wetlands” are defined in South African legislature (National Water Act, Act 36 of 1998) as being, “land which is transitional between terrestrial and aquatic systems where the water table is usually at or near the surface, or the land is periodically covered with shallow water, and which land in normal circumstances supports or would support vegetation typically adapted to life in saturated soil” (www.dwaf.gov.za). For simplicity, the Department of Water Affairs and Forestry considers all watercourses as wetlands.
In order to apply any land use or management restrictions on wetlands, these areas need to be clearly delineated. Wetlands occur along a soil saturation / flooding gradient between non-wetland and permanently flooded deep water areas. Consequently wetland regimes range from temporary soil saturation or flooding to permanent soil saturation of flooding ( In terms of delineating the edge of a wetland, Kotze et al. The presence of water results in hydric soil conditions and one can identify the edge of the wetland by differences in soil characteristics. For example, wetland soils have mottles, have a higher organic soil content, and the colour of the soil is different. Vegetation differences are also used to help determine the edge of the wetland.
Natural wetlands, covering approximately 6% of the world’s surface, have been cited as being one of the most important systems for sustaining life on this planet. The importance of wetland conservation and sustainable management is directly related to the value of the functions that wetlands perform. These functions include flood attenuation, streamflow regulation, water purification, carbon sequestration and carbon storage. Wetlands therefore perform vital functions in our environment.
In broad terms, wetlands are protected by The Constitution of the Republic of South Africa(Act 108 of 1996), which states that everyone has the right (a) to an environment that is not harmful to their health or well-being, and (b) to have the environment protected, for the benefit of present and future generations through reasonable legislative and other measures that (i) prevent pollution and ecological degradation, (ii) promote conservation, and (iii) secure ecologically sustainable development and use of natural resources while promoting justifiable economic and social development.
The National Environmental Management Act (Act 107 of 1998) also provides for the protection of the environment, and provides for the recognition that development must be socially, environmentally and economically sustainable and that the disturbance of ecosystems and loss of biological diversity are avoided, or, where they cannot be altogether avoided, are minimised and remedied. In terms of this Act, the landowner, his representatives and the person responsible for the environmental degradation can all be liable for costs. In terms of the National Water Act (Act 36 of 1998), all reasonable measures must be taken to prevent the pollution of a water resource. This responsibility extends to the owner of land, a person in control of land or a person who occupies or uses the land on which the polluting activity has occurred or could occur. The Conservation of Agricultural Resources Act (Act 43 of 1983) promotes the conservation of soil and water resources, indigenous vegetation and the control of invasive plants. Wetlands are protected by various other legislations, including the Environmental Impact Assessment Regulations (2006), which state that one needs environmental authorisation if wishing to conduct an activity within the one in ten year flood line of a river, or within 32 metres from the bank of a river or stream where the flood line is unknown, including the construction of canals, channels, bridges, weirs and dams.
The implications of this legislation is that wetlands are essentially protected and one may not without permission construct dams and river crossings, one may not drain wetlands, and one may not cause any pollution to enter wetlands. For example, the release of effluent from piggeries and dairies into wetlands is not permitted. Likewise, one is not permitted to allow soil erosion to continue unabated into wetlands. One may also not build jetties and other structures into wetlands without permission from Water Affairs and Environmental Affairs.
The author will not be held responsible for misinterpretation of the law, and strongly recommends that readers consult their local DAEA branch for clarification.