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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Political Ecology of Water Struggles in Durban, South Africa

Loftus, A. J. January 2006 (has links)
This thesis looks at the relationshp between water and social power. It attempts to answer two questions: who controls the distribution of water in the South African city of Durban? And how might this distribution be transformed in positive democratic ways? In attempting to answer these questions, the thesis provides insights into post-apartheid South African society and the possibilities for democratic social change. The framework of analysis builds upon work conducted in urban political ecology. In particular, I argue that urban environments, indeed all environments, should be understood as created ecosystems. Recognising this, I suggest that Durban's waterscape should be seen as produced through capitalist social relations. The waterscape thereby becomes a particular accumulation strategy through which profits may be generated. for Durban's communities, one of the most direct effects of this capitalist accumulation strategy is that access to water is dependent upon the exchange of money. Whilst this situation has been amerliorated somewhat through the development of a free basic water policy, the policy itself has necessitated a much tighter regulation of domestic supplies and, in effect, a more severe commodification of each household's water supply. In turn, this has resulted in water infrastructure acquiring power over the lives of most residents. This, I argue, is a result of the social relations that come to be invested within that infrastructure. The possibilities for change that are suggested lie within the struggle for feminist standpoint and the connection of these situated knowledges of the waterscpe with a broader historical and geographical understanding of the terrain of civil society. from such an understanding of civil society, a dialectical critique of hegemony is opened up. Overall, the thesis moves from an analysis of the power relations camprising the waterscape to the development of a critique from which, it is hoped, the possibilities for political change might emerge.
2

Determination of estrogenic hormones in environmental water samples in Vaal region by Ultra Fast Liquid Chromatography coupled to Mass Spectrometry

Mnguni, Sibusiso Blessing January 2016 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / The presence of estrogenic hormones in the environment has been a subject of concern in recent years; they have been classified as “emerging pollutants” and may pose a potential risk for human consumption. Hormones have been detected in ground and surface water at low concentrations. These compounds contaminate the surface and ground water via waste water treatment plants (WWTP) and may elicit endocrine disruption to organisms. Because these compounds are available at low concentration, robust analytical methods are required to quantify these compounds in water and environmental samples. The common method for the analysis of hormones in water samples is Gas Chromatography (GC) coupled to Mass Spectrometer (MS). The challenge with GC-MS is the required lengthy derivatisation step that involves toxic chemicals. The first part of this case study was to develop a method to determine trace concentrations of the Estrone (E1), 17α-Estradiol (E2α), 17 β-Estradiol (E2β) and 17α-Ethinylestradiol (EE2) hormones using Ultra-Fast Liquid Chromatography Mass Spectrometry (UFLC-MS-MS). Using the developed method, the second part of the case study was to determine the concentrations of the hormones in raw and potable water samples from the Vaal River catchment area in the South of Johannesburg, South Africa. Analytes were extracted by solid phase extraction (SPE C18 Sorbent, 200 mg/6mℓ cartridges) and subjected to Ultra-Fast Liquid Chromatography coupled to Mass Spectrometer (UFLC-MS-MS) for identification and quantification. Optimum SPE parameters were 1000 mℓ of sample percolated, at flow rate of 10 mℓ/min, sample pH of above 7, 7.5 mℓ of methanol as elution solvent followed by solvent reduction to 250 μℓ. The limits of quantification were in a range of 0.24 to 0.32 ng/ℓ for all analytes. Accuracy was 95.6, 93.8, 97.6 and 100.9% for 17α-Ethinylestradiol, 17α-Estradiol, 17β-Estradiol and estrone, respectively. In raw water samples taken during the rainy wet season, estrone was detected at concentrations of 0.90 and 4.43 ng/ℓ. However, drinking water samples no presence of hormones with the exception of M-B12 sample point where the estrone amount of 2.88 ng/ℓ was detected. This is potentially due to fact that conventional water treatment plants are able to remove the compounds during water purification process depending on the concentration levels. / LG2017
3

The status of ballast water management in the ports of South Africa.

Calitz, Fiona. January 2012 (has links)
Ballast water discharged from ships is considered to be one of the four biggest threats to oceans, as alien species, detrimental to the marine ecosystems, are introduced into domestic waters via ballast. Nevertheless, eight years after its adoption, the International Convention for the Control and Management of Ship’s Ballast Water and Sediments of 2004 remains unenforced. In the interim, the IMO has encouraged member countries to implement national ballast water policies in order to reduce the risk of alien invasions into their waters. South Africa was chosen as one of six countries in the world to participate as a pilot country for the GloBallast programme which was conducted in Saldanha Bay between 2000 and 2004. The purpose of the GloBallast programme was to assist developing countries to understand, develop and implement control measures relating to ships ballast water within their ports. The outcome of the risk assessment completed during the programme was that South Africa needed to implement a mandatory ballast water reporting system. The purpose of this study is to examine the status of ballast water management in the ports of South Africa and to determine the progress made since South Africa participated in the GloBallast programme. The methodology used in this study included questionnaires distributed to industry experts and the full population of Ships Agents that are members of the South African Association of Ship Operations and Agents. The findings show that whilst each port is reported to have a ballast water management plan; only three of the eight potential plans could be produced. Two of these plans, belonging to the ecosensitive ports of Ngqura and Saldanha Bay, were proven to be well-known amongst the agents. The other ports, however, reflected a weak 50% and lower level of awareness. It was further determined that the ships agents are largely unaware of the responsibilities placed upon them by these plans. The findings further revealed that these regulations have not been monitored or enforced and presently ballast water management would appear to be merely a paper exercise. Those ships agents who are aware and comply with the requirements report that they have never had a problem with obtaining approval to discharge ballast. Recent developments in July 2012 show that the Department of Transport has assembled a team to further develop legislation and regulations to address ballast water management in South Africa. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2012.
4

Water irrigation costs and farm outputs : a case of selected crops in Limpopo Province

Dandane, Khutso Donald January 2022 (has links)
Thesis (M. Com. (Accounting)) -- University of limpopo, 2022 / Water scarcity is a problem for many countries across the world. Limpopo Province is no exception, as the province has regions that are arid and/or semi-arid. The accessibility of water and the management of water is amongst the critical issues faced by some of the rural farmers in the Limpopo Province. The challenge of inappropriate and inefficient use of modern irrigation technologies is associated with the exorbitant investment and operation costs, resulting in poor irrigation practices by smallholder farmers in the province, mainly affecting the production of citrus, avocado, nuts, potatoes and tomato production resulting in reduced yields and revenues. The study conducted a case study on the selected crop in the Limpopo Province, which included crops such as citrus, nuts, avocados, potatoes and tomatoes. The objectives of the study are to examine the influence that investments in water irrigation infrastructure has on the volume of farm yield, as well as to examine the influence of the cost of water irrigation systems on the volume of farm yield on the selected crops. The study used a survey research design, together with a mixed-method approach, whereby 50 farmers were purposively sampled in the Limpopo province. Primary data were collected from a focus group discussion and the administration of a questionnaire. A multivariate analysis was used to analyse the data. Out of 50 farmers, only 48 responded, which is a 96% response rate. From the analysis, the study found that investment in water irrigation has a positive and significant influence on the farm yield at a 0.01 confidence level. Furthermore, the OLS regression shows that a positive and significant relationship exists between the total cost index for Citrus and the farm yield. The total cost index has a varying effect on the distribution of farm yield. It is expected that an increase in the level of education will increase revenue. Overall, the industry may also need to look at the introduction of hybrid systems that are more cost-effective, that take advantage of solar and wind energy. Future research can look at the different crops in different provinces of South Africa. / Kagiso Trust
5

An examination of Rand Water's skills development for the production of quality drinking water locally

Govender, Esthelyn Carol January 2016 (has links)
A research report submitted to the Faculty of Engineering an the built environment, University of the Witwatersrand, Johannesburg in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, October 2016. / The study investigates the effectiveness of Rand Water’s Scientific Services’ skills development strategy for the assurance of quality drinking water as prescribed by the SANS 0241 National Drinking Water Quality Standard. The aim is to establish whether: 1) the present skills are adequate to provide the scientific data required for affirming drinking water quality and 2) the skills development taking place in the Scientific Services division is adequate for the level and quantity of scientific skills required for the future. There is also some discussion to understand the motivation for maintaining and increasing skills within the Scientific Services division for Rand Water. Assuring drinking water quality within Rand Water is the sole responsibility of the Scientific Services division. The division provides regular routine and non-routine drinking water quality monitoring, testing, data collection, analyses and reporting on the organisation’s performance against the SANS 0241 Drinking Water Quality Standards (SANS, 2006).The focus of the analysis is Scientific Services Division in Rand Water, although the discussion in view of the topic is not limited to the division. Production of drinking water encompasses two key aspects that must be investigated they are quality and quantity, however the close up analyses could only be successful completed for quality in the context of the quantity produced. Skills development planning within Scientific Services has always been based on the division’s feeder pipelines to be able to recruit from and retain scientific skills within the organisation. The division concentrates on Graduate, Bursar and Experiential Learner development ensuring a sustainable, trained and readily available pipeline of skills from which to recruit. Employees currently within the division both permanent and temporary form the type of scientific skills required for water quality monitoring and drinking water standard production and assurance. Employees have been placed within the functional scientific streams of the division and further by their levels of appointment and qualifications. The data analysis has also been done for the increasing of skills using the same framework. Age and gender was also included to show performance of the division in respect to transformation and equity. Equity in relation to growth is currently a global matter that is under scrutiny. The World Economic Forum has put equity in the spotlight to ensure countries look at their performance. The significance is that it has an impact on how the water resources in a country are distributed and managed. The Water Reforms in most developing countries have sparked large scale discussions around provisioning of water for all. Human Development and Water Resource Management are agendas that countries need to handle collectively with the ultimate outcome being achieving equity for all (UNDP, 2013). Rand Water’s Scientific Service skills data indicates that it has adequate scientific capacity to meet its present mandate of providing drinking water quality assurance for the organisation. There is some concern that the aging workforce is concentrated at management and specialists levels, therefore developing these skills for the next 5 to 10 years requires immediate attention. Transfer of skills and retention of skills requires careful strategic planning in order to attract a younger transformed workforce. The study shows that in as much as routine quality assurance is core, it is also equally critical to have employees who can troubleshoot within the context of the new environmental pressures and diverse operational conditions. The demand for quality drinking water over the last 110 years has increased throughout the country. The mandatory expansion of the organisation translates into sharing of human resources with other parts of the country to produce quality drinking water. Rand Water has been entrusted to take on the responsibility of other water utilities in the country and ensure that they reach the required standard for the production of quality drinking water. The full scope of the organisation’s mandate requires that it provide skills to handle the treatment of drinking water and wastewater in the near future. Although wastewater treatment is currently managed by the local municipalities, Rand Water will be having an active role to improve services. This would mean distributing the existing capacity within the organisation over a greater area of work along with a significant increase in the demand for scientific analyses of drinking water quality. The pace at which skills development takes place in Rand Water Scientific Services division shows that it will be able to meet the present needs. There are questions raised on the sustainability of the skills for the future. Maintaining and developing skills within the division is critical to be able to sustain the nature, structure and functioning of the division in its current form. The other factor that must also be maintained is the transformational equity demands of the country. The notion that there is a lack of experienced previously disadvantages scientists must be addressed directly to meet all the future demands of the sector, region and continent in a short space of time. / MT2017
6

Impact of storm events on the transport of solutes and macronutrients in mountainous catchments under contrasting land uses at the Cathedral Peak research site, Drakensberg

Lenkwe, Aobakwe January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science August 2017. / Streamwater chemistry is influenced by several factors that include: geology, soil-geology interactions, land use, climate change, topography, vegetation, mechanical and chemical weathering. The dominance of these factors when determining the chemistry of streamwater varies from one situation to the other. Four different catchments in the Drakensberg were monitored to identify the processes determining temporal and seasonal patterns in streamwater chemistry. The land uses of the catchment include: CP03 (previously afforested, degraded), CP04 (pristine grasslands), CP06 (pristine grasslands) and CP09 (protection from fire). All the catchments were investigated for differences in major ion concentrations, streamwater temperatures, dissolved organic carbon (DOC), dissolved oxygen, pH, conductivity. There were comparisons made between historical and recent data collected at the Cathedral Peak Research Site. Comparisons were made between CP03 and CP06 to identify effects of storm events on streamwater chemistry. CP03 and CP09 had significant statistical differences in terms of major ions. Land use and stormflow path ways were most influential in determining the streamwater chemistry across catchments. / LG2018
7

The occurrence of free-living Amoebae and Amoeba resistant bacteria in drinking water of Johannesburg City, South Africa

Malaka, Maropene Patrick 13 October 2014 (has links)
M.Tech. (Biomedical Technology) / Drinking water in the greater Johannesburg area is produced by Rand Water and is transported to local Johannesburg Water where it is stored in reservoirs for distribution. At any point during the production, distribution and storage of the water, contamination with free-living amoebae, potentially containing amoeba resistant bacteria, may occur. Free-living amoebae are often resistant to the biocides used by water treatment industries and may thus be transmitted to public facilities, consumers’ homes and informal settlements through water distribution systems and during storage in small containers. The aim of our study was to analyse the water quality around Johannesburg with regard to free-living amoebae and amoeba resistant bacteria. A total of 182 tap and 5 storage tank water samples, collected from Hillbrow, Bertrams, Riverlea, Braamfischerville and Hospital Hill, were analysed for amoebae, indicator organisms, Legionellae, environmental mycobacteria, Shigella, Salmonella and Vibrio species using amoebal enrichment method. Direct microscopy indicated the presence of amoebae in 96.1% of samples. Acanthamoeba cysts were present in 69.0% of the samples. In 55.0% of these samples visibly active intracellular bacteria were observed within the sample suspensions. In the 46 samples analysed by polymerase chain reaction, the presence of Acanthamoeba species was confirmed in 65.2%, and the intracellular bacteria such as Legionella pneumophila and Mycobacterium avium was confirmed in 23.9% and 73.9% respectively. All samples indicated the presence of Shigella species while one sample contained Salmonella species on xylose lysine desoxycholate agar after amoebal enrichment processing. Vibrio species was not confirmed in the samples. Our results indicated a high risk of transmission of amoeba resistant bacteria through drinking water to people living in these areas.
8

Analysis of temporal and spatial variations in water storage by means of gravimetric and hydrologic methods in the region around the South African gravimetric observation station

Mahed, Gaathier January 2013 (has links)
This work examines the use of gravity data and its application to subsurface water reservoirs in the immediate vicinity of the South African Geodynamic Observatory, Sutherland (SAGOS), situated in a semi-arid region of the Karoo region of South Africa, and underlain by the Karoo sedimentary rocks intruded by dolerite dykes and sills. SAGOS houses the only supergravity metre (SG) in Africa, and this thesis sets out to test its use in monitoring groundwater dynamics using hydrological and gravity data. The main aim of this work is the application of the SG data, in conjunction with hydrological data, to better understand episodic recharge of subsurface reservoirs. The importance of water as a resource, globally and specifically the Karoo, is reviewed in conjunction with supply and demand of water. This is to contextualise the socio-economic, technical as well as policy issues related to water resource management. Applicable technologies for water resource management and efficient water use are highlighted and the application of gravity to hydrology is introduced, including satellite as well as ground based tools. In addition, arid zone hydrology as well as recharge and its mechanisms are analysed in order to better understand these processes when examined from gravity measurements. Issues related to understanding flow within the vadose zone as well as in secondary aquifers are examined, and gravity residuals and subsurface hydrology are highlighted. Thereafter, a conceptual groundwater flow modelof the study area is developed using multiple tools. First, the geology around SAGOS was mapped using SPOT 5 imagery and then ground truthed. Second, stable isotopes and water chemistry analysis was undertaken on water samples from selected boreholes. The results allude to preferential flow acting as the main mechanism for groundwater recharge. Follow-up pump-tests illustrate that fracture connectivity is greatest at close proximity to the dyke. Soil mapping, using aerial photography was also undertaken. Duplex soils, enriched with clay at depth, dominate the study area. Using in-situ infiltration tests, it is shown that the alluvium, which lines the river beds, has a higher hydraulic conductivity than the other soils, confirming that these streams act as preferential conduits for subsurface recharge. Precipitation events were correlated against gravity residuals at 4 wells, over different time periods. The results are examined using time series analyses. Gravity residuals from well SA BK07, over a period of 24 hours after the rainfall event, delineate instances of negative correlations, as well as strong positive correlations (of up to 0.9). On the whole however, correlations between gravity and groundwater at SA BK07 are variable and weak, and in conjunction with water level measurements and water chemistry, the data suggest that this well is located in a dynamic conduit (throughflow) and not in a permanent groundwater reservoir. By contrast, other wells show strong positive correlations between gravity residuals and water levels following episodic recharge events for a later time series. Correlations between the water levels and gravity residuals in wells SA BK04, SA BK05 and SA BK 01 are in excess of 0.7 for specific rainfall events. In summary, the results suggests that gravity is an excellent tool for measuring episodic groundwater recharge within the immediate vicinity of the SAGOS. This implies that gravity can aid in monitoring groundwater losses/gains in arid and semi-arid areas. Recommendations for future work are highlighted at the end; these include the possible use of hydrological modelling of reservoirs at various scales and then comparing these results to the SG as well as GOCE and GRACE satellites data, and then improving numerical modelling of the groundwater dynamics for sites like Sutherland and the surrounding arid Karoo region, where sparse water shortages, and potential pollution related to fracking for shale-gas, are likely to compete with established water needs for farming and human consumption. It is also suggested that the gravity modelling be examined to better understand site specific scenarios and thus aid in improving the processing of the gravity signal.
9

A liquid consumption survey of individuals in greater Cape Town

Bourne, Lesley Thelma January 1986 (has links)
There is no published data for the per capita consumption of water of individuals in South Africa. A daily rounded volume of 2 litres per person is usually taken as a working estimate from world wide data. As part of ongoing epidemiological studies into potential health effects of changes in the water supply to greater Town, water consumption patterns were ascertained. As health effects are often spatially ascribed to the place of residence of a person, it was necessary to ascertain how much water was drunk at home as well as away from home. Water consumed was divided into three classes: (i) water consumed from the tap, (ii) commercial beverages and (iii) water bound in food. A review of methods of conducting dietary surveys indicated that a 24-hour recall would be the most appropriate method. Two surveys on total dietary intake utilizing a 24-hour recall were carried out (n = 2 000 persons for each survey), one in winter and the ether in summer. The design of the survey involved a cluster sample of households that were representative of the socio-economic and demographic structure of greater Cape Town. Three pretested types questionnaires were administered by trained interviewers: (i) a placement questionnaire to describe the household composition, (ii) a recall questionnaire for individual adults and children and (iii) a recall questionnaire for babies. Particular attention was paid to the accurate ascertainment of the volumes of food and drink consumed as well as their preparation to facilitate accurate analysis. The water content of each food item was calculated by a computer program that utilized computerized food composition tables. The water consumption data was analyzed by sex, age, population group, income and the season of the year. Detailed graphs and tables are provided. Results were also standardized to the population of greater Cape Town. It was found that the difference in consumption between the White and "Coloured" population groups was greater than the difference between those people of high and low-income groups. The mean total water intake for Whites was 2.19 litres per day, while for "Coloureds" it was 1.26 litres per day. There is no obvious bias to account for this difference. The figures for protein consumed by the two groups, which was used as a control, are consistent with values reported in the literature. Summer consumption was higher than that during winter. The ratio of tap water consumed at home to total liquid consumed was approximately 0.5.
10

A feasibility assessment of the application of environmental valuation methods to Rand Water open space

Bouwer, Rinus 11 1900 (has links)
Rand Water contracted UNISA to develop a monetary valuation method for its open spaces and their inherent ecological functions. This study began by reviewing existing contemporary definitions of open space in South Africa and then identifying their key characteristics. The research project then looked at the economic contribution that open spaces make to the economy as a basis for environmental valuation. By determining the economic value of open spaces, decision makers can be informed about the importance of open space provision, preservation and maintenance. The project applied the participatory action research method which requires the active participation of focus groups. The focus groups consisted of Rand Water employees who deal with open spaces in their respective areas of work. During the literature review and problem formulation the various limitations of environmental valuation methods became evident. It became apparent that the development of new valuation methods would not be possible before existing valuation methods had been tested to see if they could feasibly be applied to open space in the Rand Water context. A literature review also determined that open space valuation studies in South Africa are very limited, which made it difficult to formulate a localised context. It was furthermore found that environmental valuers prefer to use the contingent valuation, travel cost and hedonic pricing methods. These methods rely on revealed and stated preferences of open space users to infer an economic value for an open space. Access to Rand Water’s open spaces is largely limited owing to strict access control. The excludability of open space users therefore hampers the generation of sufficient data to apply revealed and stated preference valuation methods. On the basis of this finding, it was decided to eliminate the contingent valuation and travel cost methods from this study. It was decided to apply the constraint composition theory, under the grounded theory model, to study the constraints or moderators which could affect the feasibility of environmental valuation application to Rand Water open spaces. Four moderators were then identified which could influence the outcome of the feasibility assessment. These are the limitations of the methods, the limitations of the legal framework, the limitations of the user and the limitations of the study area. It was found that the limitations of the methods were a moderator owing to their inherent data requirements. The only suitable valuation methods vi were found to be market based as they were not influenced by the excludability factor. These methods include the replacement cost, damage cost avoided, restoration cost and defensive expenditure valuation methods. The focus group was introduced to each method by participating in a method application exercise. Questionnaires regarding each method were completed to test variables. The legal framework was found not to be a moderator since even though there are limited direct provisions in legislation to mandate environmental valuation, there are legal principles which require economic impacts to be measured and damage to the environment to be estimated. These principles in themselves have supported litigation cases and the mere admission of environmental value estimates in court as evidence and support to a case therefore sets the required legal precedence and mandates further application. The user was found not to be a moderator. Feedback from the focus groups as well as an environmental resource economics workshop held at the Gauteng Department of Agriculture, Conservation and Environment showed that users understood environmental valuation principles, their benefits and limitations. With training, environmental scientists can apply these methods. The study area was found to be a moderator. The limited access for potential open space users, limited harvesting, limited agriculture and limited open space categories result in limited values that can be measured. In conclusion, it was found that not all environmental valuation methods can be applied to Rand Water open space owing to inherent limitations of the methods and the study area. Only market-based methods were found to be suitable for use on Rand Water open space. Notwithstanding the limitations of the methods and study area, which restrict the ability of valuers to obtain a total economic value for Rand Water open space, the available suite of methods can provide an indicator of value for environmental goods and services that flow from the utility’s open spaces. It was concluded that the application of environmental valuation methods to Rand Water open space is feasible within the context of the identified limitations. / Environmental Sciences / M.Sc. (Environmental Management)

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