**2. Study area**

Furthermore, the delineation of wetlands on the aeolian derived sandy soils associated with the MCP is regarded as problematic when using the soil form and-wetness indicators described by the Department of Water Affairs and Forestry (DWAF 2005) [11]. However, the distinct changes in plant species composition along the wetness gradient of a wetland provide an

indication of wetland zoning [12, 11] and therefore guides the delineation procedure.

**Figure 1.** Locality of Maputaland within the South African context

276 Biodiversity - The Dynamic Balance of the Planet

The MCP is demarcated by the Mozambican border in the north; the town Mtunzini in the south; the Indian Ocean in the east; the Lebombo Mountains in the north-west; and the N2 on the south-west. This study focuses on the northern parts of the MCP only (Figure 1).

The MCP has a subtropical climate with very hot summers and mild winters. The area receives 60% of its rainfall during summer and 40% during winter, with a mean annual precipitation of 963 mm [13]. Rainfall decreases sharply from east to west, with an approximate mean of 1200 mm at the coast, and 800 mm – 1000 mm at the crest of the Lebombo Mountains [13].

Aeolian distributed sands from the Tertiary and Quaternary period dominate most parts of the MCP. These sands are relatively infertile and of low-productivity [14]. The study area is characterized by undulating dune topography located up to roughly 70 m above sea-level [15]. In the east the Plain is separated from the Indian Ocean by an uninterrupted barrier dune system [14]. A long, relatively flat coastal plain stretches between the Lebombo Mountain Range and the coastal barrier dunes. Dune cordons occurring sporadically all over the MCP are interspersed with various wetland types such as floodplains, lakes, fens, swamp forests and pans [16]. Groundwater is the principal source of water for most of the lakes and wetlands in Maputaland [17], and moves rapidly through the system due to high permeability, high rainfall, and low water gradients. Two primary porosity aquifers are present on the MCP-a shallow, unconfined aquifer and a deeper, confined aquifer [18]. The shallow, unconfined aquifer is driven by rainfall which infiltrates and percolates through the sandy soil until it reaches the impermeable Kosi-Bay Formation, where after the water then moves laterally to exit the aquifer in the form of a surface water source.

In terms of biodiversity the MCP fall within the Maputaland Centre of Endemism Centre. This is one of Africa's most important biodiversity and endemism hotspots, and is located at the southern end of the African tropic where many plant and animal species reach the limit of their range. An assortment of diverse ecosystems and many broad ecological zones such as thicket, grassland, bushveld, forest, sand forest and swamp forest occur here [19].

Most of the wetlands occurring outside conservation areas are degraded. Local inhabitants of the area utilise the wetland areas extensively for subsistence agriculture due to the infertile nature of the sandy soil. A recent threat to the health of wetlands is the informal plantations that have sprung up all over the MCP during the past 20 years. These *Eucalyptus* plantations have a marked effect on the water table and the subsequent dynamics of the wetlands systems in the area*.* The MCP is rich in peatlands and contains about 60% of the estimated peat resources of South Africa [20]. This region contains the largest and highest density of peatlands of all the Peat Eco-Regions. It is estimated that 60 – 80% of these peatlands are currently being utilised by the local community for subsistence agriculture and other uses [21].

Five wetland types were identified and investigated in this study (Figure 2):

	- **◦** Scattered depression type wetlands between vegetated coastal dunes,
	- **◦** Linked with the regional water table,
	- **◦** Peaty soil in the pristine wetlands [33],
	- **◦** Intense local utilisation of the fertile peaty soils for subsistence.
	- **◦** A linear valley-bottom system,
	- **◦** Linked with the regional water table,
	- **◦** The permanently wet areas of the system are peaty,
	- **◦** Clay lenses occur at 300 500 mm depth on the banks of the system,
	- **◦** A series of scattered seasonal pans occurring parallel to the MS system,
	- **◦** Inside the Tembe Elephant Park the pans occur as open areas surrounded by closed woodland (PP System),
	- **◦** Outside the Park the pans are open and degraded (DP System),
	- **◦** High clay content in the soil results in a perched water table for several months per year [31],
	- **◦** The pans are clay-rich, calcareous duplex soils.
	- **◦** Located on the upland flat area between the Tembe Elephant Park and Manguzi,
	- **◦** Slightly undulating Lala Palm veld with interspersed spaces of open, moist grassland,
	- **◦** Depressions occur in large patches in the Palm Veld.
	- **◦** These wetlands are seasonal and water table fluctuation plays a prominent rolep [17].

Between three to five wetlands in each system were selected to be surveyed. These wetlands were first stratified into their various vegetation zones. Between three and five vegetation zones were identified in each wetland. For the purpose of the data collection in the field the different zones sampled were based on vegetation communities observed and not on hydro‐ logical regime. Therefore these zones were not termed 'permanent', 'seasonal', 'temporary', or 'terrestrial', but rather as Zone 1, Zone 2, Zone 3, etc (Figures 3 and 4). However after the data analysis the different zones were grouped into the different wetness zones as listed above

The Ecology and Species Richness of the Different Plant Communities Within Selected…

http://dx.doi.org/10.5772/58219

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**Figure 2.** Wetland systems occurring in the northern parts of the Maputaland Coastal Plain.

and discussed accordingly under the discussion section.
