The neotropical semi-woody perennial shrub Chromolaena odorata (L.) King and Robinson (Asteraceae: Eupatorieae) has become a serious invasive weed in the sub-tropical regions of southern Africa, resulting in the initiation of an insect biocontrol research programme at Cedara in the KwaZulu-Natal province. The programme has experienced difficulties in growing and maintaining healthy potted C. odorata plants for research, for almost ten years. In an attempt to identify possible causes of mortality, plants were grown on elevated grids in two trials; (winter-spring 2003) and (autumn-winter 2004) in Durban (subtropical region, within the natural range of C. odorata) and Cedara (temperate region, outside its natural range). Plants that established at all sites, in Trials 1 and 2, did not display any visual symptoms associated with mortality; however, results from Trial 1 indicated that plants grown in a tunnel at Cedara were physiologically stressed evidenced by lower transpiration rates despite higher vapour pressure deficits, compared with plants grown in a tunnel in Durban. Environmental stress was further indicated by the chlorophyll fluorescence ratio and a change in allocation of total non-structural carbohydrate (TNC) within Cedara-grown plants compared with Durbangrown plants. An attempt to relate mortality symptoms of unhealthy C. odorata plants with TNC content of the roots was unsuccessful but unhealthy plants had lower levels of N, P and K than healthy plants. Although mortality seem to be exacerbated by pathogenic fungi in saturated soil, infection was reduced by treating the soil with Previcur N and Benlate drench. Morphological adaptations of plants exposed to waterlogged soils include hypertrophied lenticels and new lateral roots; these were observed on the stem base of unhealthy C. odorata plants placed on the ground, that had reached a critical stage of die-back or had died back and re-sprouted. Examination of the root anatomy of C. odorata plants indicated an absence of cortical aerenchyma (interconnected system of air spaces), which may explain plant mortality in waterlogged pots wherein levels of oxygen in the soil may be reduced. C. odorata stock plants at Cedara have been placed on elevated grids since August 2004 and two years later plant mortality has been significantly reduced. Presently, the only feasible option is to grow potted C. odorata plants on elevated grids at Cedara because this allows for adequate drainage, aeration of soil and air-nipping of roots, and spacing plants on the grids also improves penetration of light. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2007.

An orthophoto map is made from a combination of different geospatial datasets such as relief, imagery, powerlines and annotation. These data sets are usually generated by different divisions within national mapping agencies. Often, when an orthophoto mapping project is to be undertaken, other functions within and outside the system, are actuated. Examples of such functions include; photogrammetric scanning, digital elevation capturing, aerial triangulation, ancillary data and imagery acquisition and map compilation. This research is underpinned by the hypothesis that different components that supply data required for generating orthophoto maps do not work as a coherent whole. This behaviour impacts negatively on the production of orthophoto maps as well as the quality of the end product and can have spill over effects on service delivery. In this research, systems analysis, client satisfaction survey and SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis are used as a collective set of tools to analyze an orthophoto mapping system (OMS) in order to mitigate this unwanted behaviour. The case of orthophoto map production at the Chief Directorate of Surveys and Mapping (CDSM) in South Africa is used. First, systems analysis, which uses the Data Flow Diagram (DFD) technique, is employed to depict the system‘s data stores, processes and data flows. This approach helps to show how the current system works thereby assisting to pin point areas that require improvement. After presenting the system ‘s processes, data stores and data flows, a client satisfaction survey, built on the criteria of; accuracy, completeness, correctness and accessibility of geospatial datasets, is conducted on one of the data stores – the Topographical Information System (TIS) database. Finally, a SWOT analysis is then done on the whole OMS to evaluate the internal and external environment under which the current system operates in. Gaps are identified and recommendations suggested. Although in this case, the recommendations are built based on the CDSM case study, it is believed they can benefit other OMS’s in similar operating conditions elsewhere. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

Many local authorities are major polluters and are ignoring each and every rule in the book. Raw sewerage is dumped in to rivers and the Vaal River is already a national health threat. Pollution of land, air and water is a common consequence by large corporations capable of causing harm to humans and other living organisms. Research on the pollution of these key natural resources is required to understand cumulative impacts, so as to take measures of precaution to minimize such pollution and reduce its consequences. Risk Assessments are therefore encouraged to identify and explore in quantitative terms, the types, intensities and likelihood of undesired consequences related to the risk of pollution. This study has identified a potential risk from creosote bleedings at Eskom pole yards and aims to explore the probability of such occurrences cumulatively so as to identify precautionary measures at the forefront of this problem to develop effective contingency plans. Soil samples were collected systematically and analysed for polycyclic aromatic hydrocarbons (PAH), a component of creosote that preserves wood. Studies have indicated that concentrations of this preservative beyond acceptable limits can impact negatively on natural resources especially water and soil. The laboratory analysed data indicates that the soil samples collected from the Howick Pole Yard were contaminated with PAH beyond the threshold values. The severity of the contamination, as determined by the application of the Risk Assessment tool, indicates that mitigation measures are essential. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2008.

Wetlands in southern Africa can be considered a rarity, forming despite a regional negative water balance and a continental background of wide scale incision. These particular characteristics lead to southern African wetlands generally forming on drainage lines, where incision has been momentarily paused and water is locally abundant. The exact evolutionary history of valley bottom and floodplain wetlands is varied. However, their development follows four main themes; 1) those that evolve due to resistant lithologies outcropping on a drainage line and acting as local base levels, 2) those that occur on the coast, with current sea level preventing drainage line incision, 3) those that arise from a particular relationship with a trunk or tributary channel that blocks a drainage line with sediment, and finally, 4) those that occur in a region of dramatic loss of confinement, resulting in the formation of a wetland alluvial fan. Despite varied histories, all wetlands share a common thread, developing along a continuum from small and steep unchanneled valley bottom wetlands to large and flat floodplain wetlands. Incision in valley-bottom wetlands is controlled by a geomorphic slope threshold, whereby for a given wetland size, a particular slope may be considered stable. Wetlands exceeding the particular slope for their size are most likely already incised, or are vulnerable to incision in the near future. This thesis examines the general evolution of drainage line wetlands, followed by a detailed study of a large coastal floodplain, the Mfolozi River Floodplain, located on KwaZulu-Natal’s northern coastal plain. The Mfolozi Floodplain is one of South Africa’s largest at 19 000ha and is located just south of the world heritage site of Lake St. Lucia, with the St. Lucia and Mfolozi River mouths occasionally joining at the coast. Although once a mosaic of Cyperus papyrus and Phragmites australis permanent and seasonal wetland, approximately 60% of the floodplain has been reclaimed since the 1920’s for large-scale sugar cane cultivation. A smaller percentage is used for subsistence farming, while the remaining lower portion falls in the Greater St. Lucia Wetlands Park (which was renamed iSimangeliso Park in November 2007). The formation of the large coastal valley in which the Mfolozi Floodplain now sits was created during a period of incision during the last glacial maximum 18 000 BP when sea level was 120m below the current level. The lowered sea level resulted in regional river rejuvenation and valley down cutting. The Mfolozi River valley became deeply incised resulting in the formation of incised meanders upstream of the Lebombo Mountains. Below the mountains, less resistant lithologies of the Maputaland and Zululand Groups allowed the development of a wide coastal valley. Following the last glacial maximum, sea level rose, reaching its present level approximately 6000 BP. As sea level rose, coastal valleys were drowned and began to infill with sediments. Above the floodplain, the Mfolozi River follows a meandering course in an incised confined valley. Upon passing through the Lebombo Mountains, the valley widens considerably from 915 m to over 6 km in just 1.15 km. This rapid change from confinement to a broad floodplain setting results in a reduction of carrying capacity of the Mfolozi River, creating a node of large-scale deposition at the floodplain head in the form of an alluvial fan. Deposition in this region causes a local oversteepening of the valley’s longitudinal profile, with a gradient of 0.1%. Contrastingly, the mid- floodplain is almost flat, with a decrease in elevation of just 1 m over almost 6 km (0.02%). The lower floodplain, where gradient is completely controlled by sea level, has a steeper gradient of 0.05%. The reason for the rather drastic slope break in the mid floodplain is currently unknown, although it may be related to faulting in the underlying Tertiary aged Zululand Group, which is currently concealed by Quaternary deposits. In addition, tributary drainage lines that once flowed into the Mfolozi River have been blocked by long-term sediment accumulation on the floodplain. As a result, these drainage lines have become drowned and provide local conditions for the formation and accumulation of peat. Besides geological setting, hydrology is commonly recognized as being the other most important factor in valley evolution. Flow in the Mfolozi River has been characterized as highly variable relative to the rest of the globe. The Black Mfolozi has the lowest Coefficient of Variation (CV) at 61%, followed by the White Mfolozi at 69% and the Mfolozi River at 79%. In addition, catchment precipitation was shown to be variable, especially when compared to global values. As a result of variable rainfall and discharge, the Mfolozi River shows hysteresis in sediment concentration on an annual scale, and there is an indication that hysteresis may also occur on a longer time scale during wet and dry rainfall cycles. This however, needs to be confirmed with a longerterm data set. Variable discharge and sediment transport leads to different floodplain processes and dynamics than would be expected for a river of regular flow. Since flow is generally very low in the Mfolozi River, and is characterised by a series of extremely large outlier flood events, the persistence of flood features is likely to be large. In addition, it is likely that extreme flood events are the primary drivers of floodplain evolution and dynamics in such variable settings. The Mfolozi Floodplain wetland study throws light on floodplain process rates, and the forces behind floodplain dynamics in such hydrologically variable settings. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2008.

This thesis contributes towards improving corporate social and environmental reporting (CSR) in South Africa, by determining what about CSR would need to be and could be improved. The sources of information for this were twofold. A comprehensive literature review, besides providing the background to the study, determined what specific criticisms have been levied against existing CSR disclosure and CSR systems. This thesis argued that many of these limitations arise out of the many primarily rule-based systems in existence and use, and that CSR should rather be based on sound fundamental principles and a conceptual framework, and be an enforceable standard i.e. with legal backing to ensure compliance. The second source of information on possible areas of improvement was from the users and or the stakeholders. In Part I of the thesis, these users or stakeholders were surveyed to determine which areas of reporting were important, and which needed to be better reported. What was important was that significant expectation gaps were found in CSR specifically regarding reporting the impacts on employees, the public and consumers and the physical and biotic environment. This provided evidence for the need for improvements in actual reporting in these traditional CSR areas, and hence il, . justification for the work ofthis thesis. Having identified areas of weakness and potential improvement in current CSR, an analysis was required to be performed to determine how these areas could be better reported. An assessment would need to be made if in fact these areas could be measured (and hence reported), which was undertaken in Part 2 of the thesis. The thesis revealed the need for improved CSR, and a greater degree of accountability and transparency by business that improved CSR could provide. It was argued that reporting, other than financial, which includes CSR should be prepared using a conceptual framework of principles, similar to that used in financial reporting, and thus a principle-based approach to CSR should be used as opposed to a rule based one. It was noted that such a principle-based approach would address many of the qualitative criticisms levelled against CSR practices, and current rule based systems. Using a systems based approach, a framework of interactions and impacts caused by businesses on social and physical systems was developed, which was used as the basis for a suggested CSR model. The model was validated using a peer and expert review process, and by comparison to the Global Reporting Initiative (GRI), which was used to represent international and South African best practice. However, it was noted that potential measurement difficulties would be encountered if the proposed model were used. It would also need to be determined what practical barriers would exist to implementingthese CSR models in business, which was the objective of Part 3 of this thesis. When the practical implementation of a comprehensive CSR system was evaluated in industry, both the proposed model and the GRI were considered. An important part ofthe measuring process was noted to be company risk assessment, often undertaken by the company's insurers. Where environmental impacts, health and safety, or other potential impacts (e.g. accidents or spills in the transport industry having significant impacts on other road users), were noted to be a significant risk, measurement systems and control procedures had been put in place by most companies. Perhaps the most significant part of risk, besides the potential loss in earning capacity, is potential litigation. Common law litigation would encourage companies to monitor and protect the health of their workers and consumers. Legislation e.g. National Environmental Management Act and Air Quality Act, would encourage companies to monitor their environmental impacts. Thus a combination of risk and legislation encourages monitoring and measurement. The findings of the third part of the thesis suggest that increased pressure should be placed on companies to become IS014001 certified as this would facilitate increased CSR reporting, however, this in itself is unlikely to occur unless increased pressure is placed on companies by (legal of customer). The author suggests that IS014001 certification would be more effective in ensuring environmental protection, than simple CSR disclosure. Significant challenges exist to the possible implementation of many of the key areas identified in the proposed CSR model (specifically where measurement problems exist), and no companies were found to be in a position to report on these aspects comprehensively. The findings of this thesis include that existing legislation and financial imperatives influenced measurement and recording of certain impacts and influences. At the same time, many managers suggested that lack of financial (and other resources), as well as the absence of legal requirements were some of the reasons why other impacts and influences were not measured. Thus it could be concluded that legislation enforcing CSR, together with financial incentives (or penalties for failure to meet such standards), could play a significant role in improving CSR in South Africa. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.

This study examines the quantitative aspects of the demographic characteristics of the Indian population of South Africa over a period of one-hundred-and-thirty years, from 1860 to 1991, within the framework of demographic transition theory. It informs us about a distinctive group of people within a country of mixed races and presents a hitherto uncollated historical account of the demographic changes of a small, specific, minority group, in a racially mixed society, within a developing country. Its emphasis lies in tracing the historical evolution and development of a demographically unbalanced population to one that today may be regarded as falling within the general demographic classification of an 'ageing' population. It is set within the framework of demographic transition theory and a discussion of the formation of this theory and its usefulness today is included in this work. Changes in the vital rates of mortality and fertility are examined in detail and an in-depth look is taken at changes in the age and sex structure over time. Apart from a detailed account of the patterns and numbers of indenture during the years 1860 to 1911, the core of the analysis is contained in three major chapters dealing with population structure, mortality and fertility. The bulk of the primary data was obtained from the results of twelve censuses between 1891 and 1991, inclusive. During the relatively short time-span of Indian settlement in South Africa, considerable demographic changes have taken place in this population. This study traces the progression of the population far beyond its original, unbalanced structure, which arose from the practice of indentured labour. After this practice was abandoned, growth and structural change took place almost entirely by natural increase, the balance of births and deaths. The population passed through the youthful, expanding stage of development to a structure that today resembles, in many ways, those to be found in most developed, industrialised countries of the world - with a slow rate of growth, a decreasing proportion of children under 15 years of age and an increasing proportion aged 60+ years. The social and economic challenges which face the Indian community today are very different from those encountered in the previous 130 years of settlement in this country and can be directly related to the extensive demographic changes that have occurred over this period. These demographic changes and their occurrence over time form the essence of this treatise. / Thesis (Ph.D.)-University of Natal,Durban, 2002.

Wetland degradation, which includes deterioration in functional performance and erosion, is a problem around the world. This has engendered a quest for causes and attempts to prevent the problem or to rehabilitate wetlands already degraded or undergoing degradation. The Craigieburn wetland system in Mpumalanga Province, South Africa has undergone erosion due to two downstream discontinuous gullies that have drained and considerably reduced the size of the wetland system. Measurements from 1954 to 1997 aerial photographs showed that over 40 years, the upper gully migrated headward over a distance of 30 m, while the lower gully eroded 522 m headward raising the question as to what caused their erosion? Prior to this study, the predominant view was that human activities, namely poor land use management within the wetland system, increased human occupation, and overgrazing on the adjacent catchment that caused a reduction in vegetation cover, were responsible for this wetland erosion. Detailed field observation, aerial photograph interpretation, soil analyses for mineralogy, chemistry and particle size distribution, landscape mapping, dumpy level survey of the wetland valley and statistical analysis were undertaken to establish the relationships between gullying and possible contributing factors. Human impacts on wetland gully development between 1954 and 1997 were estimated using the number of individual homes, and total lengths of footpaths, animal tracks and dirt roads. Agricultural activities and the stocking rate of livestock were excluded due to the poor quality of aerial photographs and lack of historical records. Results of multiple regression correlating lengths of the two gullies (upper and lower gullies) and the sum of these human factors gave a high correlation (adjusted R² = 0.92 and 0.90, respectively) but a low significance (p = 0.18 and 0.21, respectively). However, time has played a significant role in the erosion of both the upper gully (R² = 0.82, p = 0.02) and the lower gully (R² = 0.98, p = 0.02) at Craigieburn. X-ray diffraction and X-ray fluorescence spectrometry of weathered parent materials showed that the area has undergone deep weathering, supplying sediments to the wetland valley through surface run-off. The accumulation of these sediments resulted in localized over-steepening of certain sections of the valley floor with raised gradients of 0.0336 and 0.0337 at the two headcuts relative to the upper and lower non-eroding sections with lower gradients. These localized steep sections increased flow velocity and stream power and therefore stream erosivity thus triggering gully erosion. In addition to localized areas of raised valley floor, results from multiple regression showed a significant relationship (p = 0.002) between areas of earthflow scars and gully length, especially at the lower gully, thus further suggesting that physical factors are largely responsible for gully erosion at Craigieburn. Long-term climate change has resulted in the formation of two terraces, an older, D1 (USU-760, 1.67 ± 0.89 ka) and a younger, D2 (USU 761, 0.32 ± 0.08 ka). The former probably eroded during the medieval warming around 1230 AD while the younger terrace, which likely formed during the last half of the Little Ice Age, has been eroding since the renewed warming thereafter. This erosion has been exacerbated by short-term periodic or seasonal climatic changes, especially episodic summer rainfall events, which have likely played a key role in the headward migration of the two gullies. The result has been shrinkage of the wetland system by about 15 m on both sides of the valley, leaving behind a greyish soil colour indicating wet and reducing conditions in the past. These, together with dried relict mottles left behind in the soil matrix at the margin of the shrunken wetland system suggest past seasonal fluctuation of the water table engendering the belief that the wetland system once extended beyond its present limit. The overwhelming contribution of these physical factors, in addition to the fact that the two gullies predate human occupation of the study area catchment and environs, strongly argues for their responsibility in gully initiation and development at Craigieburn. Human presence and activities, which only became evident in the catchment from the 1950s onwards, may be secondary contributory factors. This conclusion encourages a rethink of previous views that human occupation and activities are solely responsible for this wetland gully erosion at Craigieburn and provides a rationale for including physical processes and climate change as factors when investigating causes of wetland erosion elsewhere. Such an understanding should be used to inform any rehabilitation or conservation efforts that are related to wetland ecosystems. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2011.

There is growing recognition internationally of the shift in natural resource management away from top-down, technocratic management towards participatory approaches that incorporate local communities and other stakeholders in decision-making. Natural resources and their management are also increasingly seen to play a role in development, providing the resources necessary to drive local economic development and poverty alleviation schemes. These shifts are evident in both forestry and fisheries literature and co-management policies. Co-management is a mature theory of participatory environmental governance. Participatory Forest Management (PFM), which is a co-management approach to governance in forest management, comprises a major shift in government policy in terms of managing the people-forest interface in South Africa. Democratic approaches such as comanagement are commendable; however, the reality surrounding the lack of capacity for decisionmaking by local people and the complex scientific nature of forest management makes the implementation of this approach difficult. This study adopts a critical approach to participatory practices in forestry, and questions whether participation is occurring or whether it is merely rhetoric - a disguise for an eco-modernist, technocratic problem solving approach that still employs top down management. Ecological modernisation is a policy-orientated discourse, which is used to construct environmental problems in a particular way, and so influence the manner in which they are addressed. The mainstream ecological modernisation approach, which is a weak ecological modernisation approach (Christoff, 1996), is arguably the prevailing mainstream environmental management approach in the developed and also latterly, the developing world (Christoff, 1996; Blowers and Pain, 1999; Murphy, 2000; Scott and Oelofse, 2005). According to Oelofse et al. (2006), Laros (2004) and Scott and Oelofse (2005) this weak mainstream approach has been transferred from the developed countries, where it has been institutionalised for over two decades, to developing countries such as South Africa, and has become the “rationale for environmental management” (Oelofse et al. 2006:61) in these countries also. However, within the ecological modernisation approach, shifts are taking place towards what Christoff (1996) refers to as ‘strong’ and Beck (1995) as ‘reflexive’ ecological modernisation, which acknowledge the use of more participatory, communicative and deliberative approaches to addressing environmental problems (Christoff, 1996; Blowers and Pain, 1999; Scott and Oelofse, 2005). The southern Cape PFM case study in South Africa is presented as an opportunity to explore these ideas. This thesis explores the relationship between PFM and ecological modernisation through an analysis of PFM discourse, and expands the conceptualisation of ecological modernisation by applying it to an environmental policy process in a developing world context. Through an analysis of the implementation of PFM using Hajer’s (1995; 2003) argumentative approach to discourse analysis, the appropriateness of the form of co-management, typified by PFM to the South African context, is challenged. Research findings reveal that the manner in which PFM is implemented in the southern Cape comprises a weak ecological modernisation approach to environmental management because the participatory element of PFM was found to be problematic. The nature of participation occurring at a local level differs greatly from the policy being advocated at a national level. The discourse of PFM has been institutionalised nationally as a policy and an approach to indigenous forest management, which resonates with strong ecological modernisation. Locally, however, although a degree of discourse structuration has occurred, it appears that the co-management approach being implemented is a weak form, which is more consistent with weak ecological modernisation. South Africa’s context as country in transition places it in an awkward position with regard to the application of ecological modernisation as an environmental problem-solving approach. A strong ecological modernisation approach would seem to be the most appropriate given South Africa’s context; however, there are limitations that indicate why a strong ecological modernisation discourse becomes weak at the level of implementation. Even if weak ecological modernisation were pursued, it would appear that South Africa might not yet be ready to apply such a programme effectively. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009.

A semi-herbaceous. pioneer plant Chryzanihtmoidts moniiifera was grown under varying environmental condition; in order to assess whether altering environmental variables would affect its hydraulic conductance and photo synthetic rates The plants were grown under sun and shade conditions, subjected to low and high watering treatments and to two different nutrient regimes. Steady-state gaseous exchange parameters, and whole-plant and leaf hydraulic conductance were measured on plants from each treatment. A key aspect of this study was to investigate how the following leaf components - petiole. major veins, minor veins and extravascular tissue - contributed to die overall resistance to water flow in the leaf (Ricaf). Vein orders were cut in specific sequences to interrupt water flow which then allowed the partitioning of leaf hydraulic resistances. The results showed that die maximum pbotosynthetic rate, under light saturating CO;. (A,^ was significantly affected by both nutrient and light treatments Environmental conditions (light, water and nutrient treatments) did not. however, affect the CO.- compensation point, or dark respiration of the measured A:C, curves for C. moniaftra. In terms of whole-plant hydraulic conductance, the shoot, stem and root were not significantly affected by environmental treatments. When investigating R«„. only the light treatments significantly affected the resistance of the petiole, extra vascular tissue, and minor vans Rf<trfc was found to be positively correlated with and contributed between 34-59 % of the total leaf resistance When considering the resistance of the leaf it was observed that the vascular tissue of the leaf contained up to 90 % of the total leaf resistance. The results from this study show that the hydraulic conductance of C. moniijfera was found to be significantly affected by light treatment; only. Water and nutrient treatments did not have a substantial impact upon the water flow of the plant. Leaf hydraulic resistance was partitioned differently to that of results from ocher studies, in that the petiole and major veins contained the majority of the leaf resistance In retrospect this study would have been more effective if C. monilitfera treatments were more severe, in terms of water and nutrients Further studies should focus on a comparison of leaf hydraulic resistance partitioning of other species, across a range of plant types. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2008.

One of the main environmental problems associated with the disposal of waste on land is the release of liquid emissions from the site. This wastewater, known as leachate, is a product of the biodecomposition of the waste and filtrates from the landfill once the moisture saturation of the fill has been reached. The chemical composition of leachate is variable over time and between sites. Regardless of these variables, the main pollutants of concern in the leachate are ammonia and organics, both of which can cause environmental degradation in relatively low concentrations. Worldwide and in South Africa, leachate has either been directly released into the environment or into the local domestic sewage system. As more has been learned about the human and environmental health risks associated with these disposal methods, there has been a new focus in waste management toward treating the leachate at the source as part of the broader focus of sustainable landfilling. One of the treatment options being used is constructed wetlands (CW) due to the physical and chemical transformation mechanisms in these biological systems. This treatment process has been demonstrated to be effective as a final polishing treatment for leachate, and it is considered a technology appropriate in the South African context. Therefore the aim of dissertation is to ascertain the use of constructed wetlands as an appropriate treatment option for untreated methanogenic landfill leachate by determining the efficiency of ammonia and organic removal in a pilot-scale vegetated submerged bed (VSB) constructed wetland (CW) planted with Phragmites australis. During the 22-week treatability trial the VSB achieved an ammonia concentration removal efficiency of 91% and mass removal efficiency of 87%. Despite this substantial reduction of ammonia, the VSB was unable to achieve the required discharge standard. There were erratic fluctuations in both the treatment efficiencies for COD and BOO, and the results show no evidence of constant reduction of organics during the treatability trials. This is due to the refractory nature and the low biodegradability of the organics that remain in methanogenic leachate as suggested by the low BOO to COD ratio. Due to the low biodegradability of the organics, a biological treatment system, such as a VSB, will not be able to reliably meet the required discharge standards. Other passive treatment options or a combination of systems need to be explored in order to both satisfy legislative requirements and be appropriate in the South African context. / Thesis (M.Sc.)-University of Natal, Durban, 2003.