The aim of this research was to investigate the possibility of using soil magnetic susceptibility to differentiate wetland soil from non0wetland soil, thereby enabling the identification of a wetland boundary. The initial methodology to test the viability of using magnetic susceptibility for wetland delineation was carried out at nine sites in three areas of Kwazulu-Natal, South Africa. Changes in vegetation were used to identify the permanently, seasonally and temporarily wet zones at each site to provide a quick indication of the various boundaries. At least one transect was studied at every site, extending from the outer edge of the temporary zone to the water's edge. Magnetic susceptibility readings, soil samples and/or elevations were taken in each zone. It was found that the magnetic susceptibility readings could be used to differentiate between the various wetland zones but boundaries were not identified due to the reconnaissance nature of the work, a specific protocol had yet to be discovered. This methodology was a reconnaissance phase to assess the potential of using soil magnetic susceptibility. A second methodology was designed specifically to identify a wetland boundary. The wetland zones were identified using vegetation indicators from the South African field procedure for delineating wetlands. Magnetic susceptibility readings were done on transects perpendicular to the suspected boundary and a critical value was identified. A magnetic susceptibility boundary was marked according to the critical value and verified by taking readings along transects parallel to it on both sides. The boundary was then identified using South African field procedure according to soil indicates. The soil data showed a similar boundary to the magnetic susceptibility boundary but indicated a 'boundary zone' of approximately l2m in width rather than a specific line. A final methodology was planned to improve the resolution of the magnetic susceptibility boundary. A grid was laid out over a strip through the wetland including the boundary area on both sides. This was to provide accurately spaced points at which to take magnetic susceptibility readings and elevations. The critical value, a value that separates wetland from non-wetland soil, was identified and verified using soil indicators. The field procedure was more difficult to carry out than using the magnetic susceptibility sensor, yet both methods identified the same boundary with a resolution of about 3m. This initial study demonstrates the potential for using magnetic susceptibility for wetland delineation. Although the results at the final site proved the method to be successful, it was not suitable for use at all sites and the results were often difficult to interpret. Limitations include factors such as plinthic horizons close to the soil surface and shallow, rocky soils. Thus further research is required before magnetic susceptibility can be used to delineate wetlands in KwaZulu-Natal, South Africa. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.

The purpose of this research document was to determine a relevant, responsible and appropriate architecture for the design of an Environmental Research Facility for the iSimangaliso Wetland Park World Heritage Site in Northern KwaZulu Natal, South Africa. The nature of this architecture was generated through the investigation of current literature, case and precedent studies and personally conducted interviews with a number of informed professionals. The reason for these recommendations was ultimately the design of the facility for research and education, the goal was always the eventual application of the findings into a design. Ultimately, an appropriate architecture for an Environmental Research Facility for iSimangaliso Wetland Park, a UNESCO World Heritage Site, is one which is accountable and responsible regarding the social, economic and environmental aspects of its design. These three rubrics of sustainability were then unpacked and investigated in order to clarify how this would be most effectively be achieved in the eventual design. / Thesis (M.Arch)-University of KwaZulu-Natal, Durban, 2008.

In many of the rural areas of South Africa local communities rely on wetland resources for daily living. For a symbiotic relationship to exist between these communities and the wetlands, the wetlands must be utilised in a manner sustainable to both parties. To prevent exploitation thereof, a comprehensive understanding of the processes and functions of wetlands, of the values and needs of rural community members, and of the interactions between these entities is essential. This study focuses on research at three scales; the plot scale (10m\ the microcatchment scale (lkm2 ), represented by the Craigiebum wetland and microcatchment, and the catchment area upstream of the gauging weir X3H008, all of which exist in the Sand River catchment in the Mpumalanga and Limpopo Provinces of South Africa. Relationships between the geomorphological properties of the Craigiebum microcatchment, the wetland management practices of the local communities, and the hydrological properties of the microcatchment have been investigated. Various hydrological models, but in the main the ACRU model, have been adopted as tools to facilitate this research. Possible scenarios of changes in land use, rainfall and soil texture were performed at the plot scale and at the scale of the microcatchment, and changes in wetland extent were simulated and analysed at the scale of the catchment. Results of the modelling exercises simulating the effects of differences in soil texture higWight the positive effects of retention of fine particles within a wetland in a sandy environment. These results also depict greater rates of hydraulic conductivity, erosion and desiccation within coarse-textured soils than fmer textured soils. Low levels of fertility can also be attributed to the lack of fine particles present in the soils of the Craigiebum microcatchment wetland. Results of the modelling exercises that investigate the likely hydrological effects of a variety of land uses within the Craigiebum microcatchment verify accepted hydrological theory, as they highlight that more impervious areas produce more stormflow and lose more water to evaporation, and that the natural vegetation of the area contributes to streamflow regulation more than other land uses do. The exercises performed at the scale of the Sand River catchment do not provide conclusive evidence of the effects of changes in wetland extent, as the hydrological effects that other land uses in the area have appear to override the effects of the simulated wetland areas. Analysis of the sociological data captured highlights the great extent to which the local community depends on the Craigieburn wetland resources for a variety of livelihood strategies. Furthermore it illustrates the degree to which a reduction in wetland health negatively impacts upon the community. Viewed in conjunction, the hydrological, biophysical and sociological results highlight the degree to which changes in one aspect of the environment affect other aspects thereof, thereby highlighting the degree to which these aspects of the Craigieburn microcatchment are inextricably linked. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

The study sheds light on the occurrence and development of earth mounds in the Mkhuze Wetlands, KwaZulu-Natal. It compares this system with the Okavango Delta. The conceptual model developed by Ellery and co-workers for mima mound development in the Okavango Delta is said to have worldwide applicability (Ellery at al. 1998). This study investigates the applicability of this model in the formation and development of earth mounds in Mkhuze Floodplain. The activities of termite species are regarded as responsible for the formation of earth mounds in the Okavango Delta. The Mkhuze Wetlands represent one of South Africa’s most pristine wetland systems (Cowan 1995). They have also been declared as part of the Isimangaliso Park, a World Heritage Site (Cowan 1995). Many studies have been conducted in Mkhuze Wetlands in order to gain more knowledge and understanding of how the system functions, so that it can be managed wisely. Although termites are thought to be associated with these features (Adams 2004), very little has been done to assess or even verify if the changes in soil chemistry and mineralogy across these mounds can be linked to termite activities. This study investigates the soil mineralogy and physico-chemical properties across mounds found in the Mkhuze Wetlands and determines through its findings any possible link to termite activities. Most mounds in Mkhuze were identified in the intermittently flooded region of the floodplain. Results from particle size analysis were indicative of a bimodal distribution in mound soils. Two major components in mounds were a combination of clay size particles, silts and very fine sand, and fine to medium sand, with traces of coarse sand. There was a significant difference in the distribution of soil particle size fractions found on mounds compared to soils adjacent to the mounds. The chemical composition of the clay size particles found on the mounds was different when compared to that found in adjacent soils. There were also higher concentrations of minerals derived from solute chemicals found in the centre of the mounds at depth. Precipitation of solutes in mid regions of the mounds is thought to attest to spatial evapotranspiration rates across mounds. Although no direct evidence of termites was found in the mounds, there are indications that termites have been responsible for the development of the mounds and that in certain mounds plants have led to mound growth due to precipitation of solutes driven by evapotranspiration. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.

Dartmoor Vlei is a 42ha un-channelled valley-bottom wetland system located in the headwaters of the Myamvubu River in the KwaZulu-Natal Midlands, South Africa. The wetland and its catchment are entirely underlain by a large dolerite sill that forms the Karkloof escarpment and plateau and the wetland terminates against a dolerite dyke ridge that has intruded into the sill. Wetlands on the Highveld and KwaZulu-Natal Midlands are thought to arise due to the lateral erosion of valleys upstream of resistant lithologies that impede vertical erosion. This is typical of valleys where Karoo sediments occur upstream of resistant dolerite dykes. Such valley widening by lateral planing is typically associated with actively migrating meanders. As a result, wetlands found upstream of dolerite intrusions are generally located on floodplains characterised by actively migrating meanders, extensive backswamps, ox bow lakes, alluvial ridges and clastic alluvial fill. However, in contrast to these floodplain wetlands, Dartmoor Vlei has evolved into an unchannelled valley-bottom wetland characterised by diffuse flow conditions, minimal channelled flow, extensive peat deposits and a general lack of floodplain features. Coring within the wetland has established that the sedimentary fill of the wetland generally comprises upward fining sequences of sediment characterised by sands and gravels near the valley floor that grade into fine organic-rich silt sediments and peat at the surface. These findings confirmed that the wetland has evolved from a floodplain wetland characterised by laterally migrating meanders to a valley-bottom wetland characterised by discontinuous streams and peat accumulation. Coring also established that the wetland is predominantly underlain by residual saprolite that extends to depths in excess of 7m. The occurrence of a large discontinuity between the residual saprolite and fresh dolerite surfaces underlying the toe of the wetland indicated that the residual saprolite surface has sagged relative to the fresh dolerite and dolerite dyke at the toe of the wetland over time. Chemical and mineralogical analyses of fresh dolerite and residual clay within the valley confirmed that the chemical transformation of the dolerite bedrock into residual clay has resulted in both volume and thickness losses in the weathered dolerite sill mass. This has in turn resulted in the sagging of the valley floor and the wetland surface over time. These findings provide an explanation for the extremely low energy conditions of Dartmoor Vlei and explain why the wetland did not evolve in the same fashion as other wetlands in a similar geological and geomorphological setting. The extensive chemical weathering of the dolerite sill underlying the wetland has been attributed to the extremely long-time period that the soils within the wetland have been saturated. The long-term saturation of soils within Dartmoor Vlei has been facilitated by the formation and preservation of the African Erosion Surface on which Dartmoor Vlei is located. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.

Global trends of transformation and loss of wetlands to other land uses has deleterious effects on surrounding ecosystems, and there is a resultant increasing need for improved mapping of wetlands. This is because wetland conservation and management depends on accurate spatial representation of these systems. Current approaches to mapping wetlands through the classification of satellite imagery typically under-represent actual wetland area, and the importance of ancillary data in improving the accuracy in mapping wetlands is recognized. This study uses likelihood estimates of wetland occurrence in KwaZulu-Natal (KZN), South Africa, using a number of environmental surrogate predictors (such as slope, rainfall, soil properties etc.). Using statistical information from a set of mutually independent environmental variables in known wetland areas, conditional probabilities were derived through a Bayesian network (BN) from which a raster layer of wetland probability was created. The layer represents the likelihood of wetlands occurring in a specific area according to the statistical conditional probability of the wetland determinants. Probability values of 80% and greater also accounted for approximately 6% of the KZN area (5 520 km²), which is substantially more than the previously documented wetland area in KZN (4% of the KZN area or 4 200 km²). Using an independent test dataset, Receiver Operating Characteristic (ROC) curves with the Area Under Curve (AUC) analysis verified that the final model output predicted wetland area well (AUC 0.853). Based on visual comparisons between the probability layer and ground verified wetland systems, it was shown that high wetland probability areas in the final output correlated well with previously highlighted major wetland and wetland-rich areas in KZN. Assessment of the final probability values indicated that the higher the probability values, the higher the accuracy in predicting wetland occurrence in a landscape setting, irrespective of the wetland area. It was concluded that the layer derived from predictor layers in a BN has the potential to improve the accuracy of the KZN wetland layer by serving as valuable ancillary data. Application of the final probability layer could extend into the development of updated spatial freshwater conservation plans, potentially predicting the historical wetland extents, and as input into the land cover classification process. Keywords: ancillary data, Bayesian network, GIS, modelling, probability, wetland mapping. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.

Wetlands are considered sensitive eco-tones that provide numerous goods and services, not only to the communities which are immediately dependent upon them, but also to the many downstream stakeholders who benefit from the hydrological influences that wetlands have on a catchment. The three main objectives of this study, the foci of which included an assessment of impacts of wetlands on catchment hydrological responses (viz. flood attenuation and streamflow regulation) in the Thukela catchment under varying geographical and climatic conditions, are: · A modification and validation of the ACRU Model’s Wetland Routine; · Assessing impacts of wetlands on hydrological responses from catchments in varying climatic regions under historical climatic conditions; and · Assessing impacts of wetlands on catchment hydrological responses for climate change scenarios by using outputs from a Regional Climate Model (RCM). The ACRU Model was selected to undertake the daily hydrological simulations, while historical climate data and climate information derived from the C-CAM Regional Climate Model were used as inputs into the model. These varying climatic inputs, as well as the changes in water fluxes between simulations with and without the wetlands routine switched on, enabled the author to assess the impacts of wetlands on catchment hydrological responses under varying climatic conditions. The ACRU wetland routine initially did not produce output in line with conceptualisation of wetlands processes. As a result of this, certain modifications had to be made to the model to ensure that the results obtained mimicked wetlands hydrological processes realistically. A validation was performed on the re-configured ACRU wetlands routine to show that the simulated results of impacts of wetlands on catchment hydrological responses were realistic when compared to findings from the literature review (e.g. in regard to streamflow regulation and flood attenuation). These validation results also show that the impacts of wetlands on catchment hydrological responses are dependent on the level of soil water saturation of the wetland at the start of a streamflow event and the volume of the streamflow event in relation to the relative size of the wetland. The results further illustrate that wetlands have a relatively small flood attenuation and streamflow regulation impact on mean annual catchment hydrology at the outlet of the 29 136 km2 Thukela catchment. However, mean monthly results show pronounced effects (20 – 30%) of flood attenuation in the summer months and streamflow regulation throughout the year, especially in the drier winter months. The climate change scenario results illustrate that the impact of wetlands on hydrological responses are virtually entirely masked by the impact of climate change, with only minor changes shown on outflows of the Thukela between climate change scenarios without and with wetlands. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Wetlands serve many purposes in the landscape and are under increasing threat as a consequence of urbanisation despite their importance directly and indirectly to humans. Through an evaluation of the suitability of the WET-Health and WET-EcoServices tools in determining wetland functionality and the provision of goods and services of the wetlands, it was decided that these tools were particularly appropriate for fulfilling the purpose of this research. WET-Health, used in combination with WET-EcoServices, is effective in determining the overall health of wetlands and provides possible reasons for degradation which reduces the ability of wetlands to supply the benefits associated with the particular hydrogeomorphic type. A feedback and questionnaire survey was conducted with eThekwini municipality to determine if the WET-Health and WET-EcoServices tools satisfied their needs and to ascertain whether these tools would be suitable for management of their wetlands. This research, in collaboration with eThekwini municipality’s Planning Department, seeks to contribute to the management and maintenance of wetlands within the uMdloti Catchment so that more informed wetland management decisions regarding wetland sustainability can be made. A level 1 and 2 WET-Health and WET-EcoServices assessments were applied to three sites namely; the Robert Armstrong, Le Mercy and Lake Victoria Barn swallow roosting wetlands. A WET-Health Level 1 assessment can be considered more feasible than a Level 2 which provides similar results yet is more time consuming, however, expert knowledge and experience with the tool may be necessary. A Level 2 WET-EcoServices assessment is recommended as it not only highlights what benefits are being provided but the extent of each benefit thereof also determining whether a wetland has a greater chance to provide a particular benefit but may not being effective in doing so. This in turn allows for efforts and resources to be directed towards improving wetland management and land-use planning and decision making for which the tools are particularly suitable. The tools were considered appropriate and necessary for wetland management and can be adapted into eThekwini municipality’s work situation. The tools provide a holistic approach for wetland assessment as catchment activities are considered. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Hlatikulu Vlei, situated in the foothills of the Natal Drakensberg, is one of the priority wetlands in KwaZulu-Natal, occupying an area of 733 Hectares. The importance of Hlatikulu Vlei lies in its functions to store water, regulate stream flow and attenuate floods, as well as to provide suitable habitat for wildlife and grazing for livestock. Hlatikulu Vlei is a threatened system and has suffered the effects of human mismanagement. Forty-nine percent of the vlei has been classified as disturbed or destroyed, mainly due to the construction of two large dams and past drainage of vlei to facilitate pasture planting. The effects of grazing and fire on the plant communities has been considerably less. Vegetation communities at Hlatikulu Vlei have similarities with those at Ntabamhlope Vlei. The main plant communities present at Hlatikulu Vlei are: vlei grassland, sege-meadows, bulrushes and reedswamp. Species compositions of the mixed sedge and grass sedge-meadow community have a notably higher species diversity than similar communities sampled at Ntabamhlope Vlei and the mires at Highmoor. Soil type and moisture content are shown to be the most significant environmental factors determining the distribution of plant communities and species within the vlei. A wetland re-establishment and rehabilitation programme in the Hlatikulu Crane and Wetland Sanctuary has been effective in allowing many wetland plants to become reestablished. The sanctuary communities bear greater similarity to the sedge and rush sedge-meadow community, than the mixed sedge and grass sedge-meadow communities that were originally present. This is also reflected in the seed bank. All three Southern African crane species (Blue, Wattled and Crowned Crane) and fourteen species of waterfowl have been recorded in the Hlatikulu Crane and Wetland Sanctuary since the wetland rehabilitation programme. The waterfowl play a role in the dispersal of seeds into the sanctuary, particularly those of Schoenoplectus decipiens and Eleocharis dregeana and are in part responsible for the return of certain wetland plants to the sanctuary. The flooding of soils, the fluctuating water level and the soil type related to hummocks and to channels are shown to be responsible for the location of Cyperus denudatus, Arundinella nepalensis and Aristida junciformis in differing positions in the channels and on the hummocks and are also responsible for the maintenance and functioning of the hummocks and channels. Seed banks on the hummocks are similar to seed banks in the channels, however the extant vegetation on the hummocks is distinctly different to that in the channels. Certain species represented in the channel seed bank are being excluded from surviving to maturity. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1996.

Wetland vegetation is of fundamental ecological importance and is used as one of the vital bio-indicators for early signs of physical or chemical degradation in wetland systems. Wetland vegetation is being threatened by expansion of extensive lowland areas of agriculture, natural resource exploitation, etc. These threats are increasing the demand for detailed information on vegetation status, up-to-date maps as well as accurate information for mitigation and adaptive management to preserve wetland vegetation. All these requirements are difficult to produce at species or community level, due to the fact that some parts of the wetlands are inaccessible. Remote sensing offers nondestructive and real time information for sustainable and effective management of wetland vegetation. The application of remote sensing in wetland mapping has been done extensively, but unfortunately the uses of narrowband hyperspectral data remain unexplored at an advanced level. The aim of this study is to explore the potential of hyperspectral remote sensing for wetland vegetation discrimination at species level. In particular, the study concentrates on enhancing or improving class separability among wetland vegetation species. Therefore, the study relies on the following two factors; a) the use of narrowband hyperspectral remote sensing, and b) the integration of vegetation properties and vegetation indices to improve accuracy. The potential of vegetation indices and red edge position were evaluated for vegetation species discrimination. Oneway ANOVA and Canonical variate analysis were used to statistically test if the species were significantly different and to discriminate among them. The canonical structure matrix revealed that hyperspectral data transforms can discriminate vegetation species with an overall accuracy around 87%. The addition of biomass and water content variables improved the accuracy to 95.5%. Overall, the study demonstrated that hyperspectral data and vegetation properties improve wetland vegetation separability at species level. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.