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other associated high water levels. Floodplain marshes are normally elevated above the rest of
the estuary, and are normally only covered with water during large flood events.
Mucina et al. (2003) described and classified 11 salt marsh plant communities at the Uilkraals
Estuary. Dominant species included Salicornia meyeriana, Sarcocornia perennis agg., S.
capensis, S. decumbens, Bassia diffusa, Limonium sp. nova, Juncus kraussii subsp. kraussii,
Sporobolus virginicus and Triglochin bulbosa. In a 1981, study the saltmarsh covered an area of
approximately 1.3 ha or 0.6% of the studied estuarine region (Heydorn & Bickerton 1982) and
had the highest cover (95%) of all recorded vegetation types. A more recent vegetation study
recorded approximately 38 ha of saltmarsh, which is still the highest cover of all recorded
vegetation types and is of high conservation importance.
Figure 13. Picture of the upper channel and saltmarsh area facing upstream, February 2010.
Reeds and sedges
Reeds and sedges act as natural biological filters, they are important for bank stabilisation as
they are rooted in soft intertidal or shallow subtidal strata (Adams et al. 1999). Reeds and
sedges contribute to the diversity of aquatic life, particularly the avifauna (Coetzee et al. 1997).
Terrestrial vegetation
Parsons (1982) identified 10 main terrestrial plant communities around the Uilkraals Estuary,
including the saltmarsh (Error! Reference source not found.). These can be consolidated into
five plant formations visually: low shrubland (0.25-1.0 m), mid-high shrubland (1-2 m),
woodland, herbland and grassland. In the study area (205 ha) the low shrubland was the most
extensive (39 ha), followed by the herbland (37 ha) and woodland (32 ha). Mid-high shrubland
Uilkraals Estuary Situation Assessment
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