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Mangrove response to water level changes at the Nxaxo-Ngqusi and St Lucia Estuaries

  • Authors: Julie, Corianna Lauren
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53644 , vital:45689
  • Description: Water level variability within an estuary can vary as a function of tides (inundation frequency and duration) and rainfall, acting as one of the main determinants of mangrove growth, diversity, productivity, and distribution. Understanding how mangroves respond in estuaries to water level variability provides baseline information which can be used to predict future changes in mangrove growth and distribution in response to this driver This study measured mangrove characteristics (growth, structure, and areal extent) in two estuaries that differed in tidal setting, and thus water variability; the Nxaxo-Ngqusi and St Lucia estuaries, South Africa. These estuaries are part of a long-term monitoring programme (2010 - 2020) that has recorded mangrove responses to environmental changes. At the Nxaxo-Ngqusi Estuary, long-tem sea-level data (2003 – 2018) collected from the nearest tide gauge, and mangrove growth and areal extent were used to assess mangrove characteristics in a permanently open, micro tidal setting.Additionally, short-term water level data (August 2019 – September 2020), measured with in situ loggers, and sediment input at different sites within the mangrove forest, were also measured. Data was collected along the main channel sites, and at previously set up cattle exclusion plots ( browsed and non-browsed sites set to establish the effect of cattle browsing on mangroves). Similarly, at the St Lucia Estuary, long term water level data (2004 – 2020) collected at the bridge in the lower reaches of the estuary by Ezemvelo KZN-Wildlife, and annual mangrove growth, structure and areal extent data were used to assess mangrove characteristics in an estuarine lake that undergoes cycles between hypersaline and freshwater-dominated states. The results showed that mangrove responses to water level changes are complex and depend on several factors such as estuary mouth dynamics, anthropogenic activities, and site-level environmental conditions. The first objective was to compare water level changes and mangrove structure (mangrove height, and pneumatophore characteristics such as height, density and % aerenchyma) and sediment input between different sites at each estuary. Mangrove growth was higher at sites where longer inundation and higher inundation frequency were recorded at the Nxaxo-Ngqusi Estuary. However,longer inundation periods under closed mouth conditions resulted in stunted growth and mangrove dieback at St Lucia Estuary. At the Nxaxo-Ngqusi Estuary, mangroves at the main channel sites, closer to the water’s edge, had an overall higher growth rate (2.8 – 45.9 cm yr-1) than the mangroves found at the browsed (0 – 25 cm yr-1) and non-browsed sites (0 – 25.3 cm yr-1) on the landward edge of the forest. The effect of cattle browsing at these sites forms part of a long-term monitoring programme and this disturbance could have also influenced the results. Mangrove growth rate was higher in years with more rainfall at all sites within the estuary. At the St Lucia Estuary, mangrove growth rate was highest (0.81 cm yr-1) at a lower mean water level range (0.13 – 1.72 m) between 2010 - 2015, and growth rate was lowest (1.3 cm yr-1) in higher mean water level range conditions (0.34 m – 2.18 m) between 2015 – 2020. When water levels increased by up to 1.1 m due to closed mouth conditions, this led to extensive mangrove dieback further upstream by 2015. The maximum tidal flooding depth and inundation period influenced pneumatophore structure (height, density, and % aerenchyma) at the Nxaxo-Ngqusi Estuary. Sediment accumulation was highest at sites with increased pneumatophore density, but accumulation rates at the Nxaxo-Ngqusi Estuary (0.4 – 0.7 g over a high tide lasting 4-5 hours) were low and did not lead to smothering of the pneumatophores. Total sediment accumulation was highest at sites that experienced greater flooding depths. Increased inundation at the St Lucia Estuary caused inundation stress which led to mangrove mortality. This is because these mangroves are found in a closed estuary where increased water levels lead to prolonged submergence of the pneumatophores. A decrease in mangrove area was recorded at both sites. Low rainfall coupled with cattle browsing caused a decrease in mangrove area of 22% between 2009 and 2019, particularly along the mangrove fringe area at the Nxaxo-Ngqusi Estuary. The mangroves at the St Lucia Estuary, however, experienced mangrove dieback at all sites, with Site 1 recording the greatest percentage decrease in area of 71.7 % (loss of 44.76 ha) between 2010 and 2020. This was related to the progressive increase of freshwater input and water level at St Lucia Estuary under closed mouth conditions. The years leading up to 2019 had peaks in water levels at the St Lucia Estuary, with the highest water level of 2.12 m in 2019 since 2002. As a consequence, there was increased reed growth, where reeds expanded by 58% (177 ha) due to the high influx of freshwater, and no tidal exchange, which occurred in conjunction with a loss of 60.% (42 ha) of the original mangrove extent at the St Lucia Estuary. This study shows that increased water level changes (inundation frequency and duration) at the Nxaxo-Ngqusi Estuary maintain healthy mangrove stands. This is in contrast to the St Lucia Estuary, where there was a loss of mangroves as a result of high water levels under closed mouth conditions. Mangrove growth and extent at the Nxaxo-Ngqusi Estuary fluctuated in response to drought, and trampling and browsing by livestock. Extensive inundation and lack of tidal exchange reduced mangrove growth and extent at the St Lucia Estuary, with mangrove dieback occurring at all sites. These two systems are representative of the dynamic conditions found in South African estuaries. These research findings suggest that the continuous effects of climate change on estuarine habitats could result in changes in estuary mouth dynamics, which could impact mangrove growth, structure, and extent. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2021
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  • Date Issued: 2021-12

Mapping the importance of public participation in the expropriation of land without compensation bill: a case of Silver Town in KwaZakhele, Port Elizabeth

  • Authors: Ngwabeni, Siyasanga
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/54541 , vital:46686
  • Description: The post-1994 era in the South African public imagination was envisaged to herald widespread and transformative efforts to reverse the gross injustices and human rights violations inflicted over many decades of apartheid and colonialism. One of the key measures initiated by the democratic government to drive this nation building project was the land reform programme. The ‘land question’, which is a popular tagline in South Africa when reference is made to land reform, has come to define the general discourse of socioeconomic disadvantage and change in the post-apartheid and post-colonial period – similarly to other former settler colonies in the African continent and the broader Global South. For South Africa though, this specific issue has been characterised by numerous challenges and failures largely at the level of the state, wherein a significant lack of public engagement, public participation and democratic redistribution was not being done according to ‘the will of the people’. On a number of occasions, the South African state has gone on a ‘solo crusade’ to implement the land reform programme under complex conditions that are largely unfavoured by ordinary people ‘on the ground’ – especially those who were the primary victims of land dispossession under colonialism and apartheid. As a result, over the past few years, indigenous black communities across the country especially in (semi)urban and township areas have voluntarily ‘occupied’ land at their own will and sometimes ‘illegally’, as a way to take up settlement space and determine their lives on the land of their birth. Beyond the public discourse of ‘land invasions’ and ‘failed land reform projects’, this study was conducted to closely understand the extent to which public engagement and participation has been integral in the systematic mechanism(s) to transform the patterns of land ownership and control in the democratic South Africa. To do this, the site of KwaZakhele, Silvertown, in Port Elizabeth was selected to conduct the study. This township is an outcome of apartheid geography and land dispossession where many generations of indigenous black people were displaced. Today, it is a struggling community characterised by high rates of poverty and unemployment – and one of its unresolved socio-political issues is the question of the skewed patterns of land ownership in the area. Methodologically, qualitative semi-structured interviews were utilised to conduct the study and the Marxist Concept of Citizenship was selected as a theoretical framework for the study by the researcher. The study has found that, amongst the general legislative and political shortfalls of public participation breakdown, there are other deep seated structural socioeconomic issues that are at the root of the problem – such as economic inequalities and very low prospects of social mobility – which collectively reproduce the persistent inadequacies of political instability and social unrest in the area. The study recommends an astute combination of ‘bottom-up’ active citizenship and major socioeconomic transformation in the area as a systematic and structural mechanism to empower the community of Silvertown to be the champion of its own liberation struggle for the freedom of its people to own land and democratically participate in their own governance, self-determination, and prosperity. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
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  • Date Issued: 2021-12

Mentoring candidate quantity surveyors in South Africa

  • Authors: O’Connor, Nicole
  • Date: 2023-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , Thesis
  • Identifier: http://hdl.handle.net/10948/66172 , vital:74429
  • Description: Abstract. , Thesis (MSc) -- Faculty of Engineering, the Built Environment and Information Technology, School of Built Environment Environmental, 2023
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  • Date Issued: 2023-04

Microstructural characterization of Swift Heavy Ion (SHI) induced rotation in single crystal NiO

  • Authors: Douglas-Henry, Danielle
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53648 , vital:45685
  • Description: Swift Heavy Ions (SHI) are characterised by having energies greater than 1 MeV per nucleon with an atomic mass greater than 6 amu. Exposure to irradiation of this type has been known to produce latent tracks in insulators. This is due to the energy loss through the material being governed by electronic excitation processes. The extent of the track formation and microstructural changes induced has been reported to be material specific. Models such as the thermal spike model have been used to explain these changes, however rough approximations are still made. A particularly under studied phenomena is the collective rotation seen in materials exposed to off-normal incidence irradiation. To date the only available experimental data is X-Ray Diffraction (XRD) spectra and surface shifts. This does not allow for depth-dependent rotation studies and very little can be deduced regarding the microstructure of the modified volume. In this study, the microstructural changes in single crystal Nickel Oxide (NiO) have been studied using electron microscopy techniques. A depth dependent investigation of the crystal rotation was performed using Selected Area Electron Diffraction (SAED), Transmission Kikuchi Diffraction (TKD) and Electron Backscatter Diffraction (EBSD). Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) were utilized to interrogate the microstructural changes facilitating the bulk rotation. Five different NiO specimens were investigated. Specimens had surfaces parallel to either the {0 0 1} or {1 1 1} planes. Ion energies used were 593 MeV, 940 MeV and 1.6 GeV, while fluences ranged from 1.0 x 1011 ions/cm² to 9.6 x 1014 ions/cm². Latent track formation in both low fluence (nonoverlapping regime) and high fluence (overlapping regime) specimens were investigated and compared. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
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  • Date Issued: 2021-12

Murraysburg

National minimum wage : a comparative study between Germany and South Africa

  • Authors: Tshete, Vusumzi Victor
  • Date: 2021-04
  • Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , Minimum wage--Law and legislation
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/51183 , vital:43227
  • Description: This comparative research study attempted to provide the comparative analysis between the Germany’s MiLoG and the South African NMWA. The study has adopted the ILO definition of the Minimum Wage as the minimum amount of remuneration that an employer is required to pay wage earners for the work performed during a given period, which cannot be reduced by a collective agreement or an individual contract The Desk review was an appropriate data collection method for the present research studies. Desk research refers to secondary data that was collected without fieldwork. This included reviewal of libraries and the internet, that includes Journals; newspapers; clippings; reports; government statistics; dictionaries; books, On-line databases, Internet sources, legislations and case laws. The multiple research questions that will be addressed by the study question involve the regulation of the implementation of the NMW, the effectiveness and efficiency of the implementation of the NMW between South Africa and Germany, the impact of the NMW in addressing inequality, poverty and unemployment or socio-economic challenges, as well the overall role of the NMW in the entire labour between the two countries. The present study conducted a literature review on the historical development of the Minimum Wage in South Africa and Germany, the legislative framework around the Minimum Wage in both countries. The literature review also covered the impact of NMW on poverty alleviation and Wage inequalities. The literature further covered, the differences between the implementation of the MiLoG in the case of Germany and the NMWA in the case of South Africa. The literature also covered adjusting amendment and monitoring compliance including the best practices. The findings of the study is that the overarching purpose of introducing a NMW had multi- faceted purpose function such as of transforming the country’s inordinately unequal wage structure while at the same time redressing the inherent poverty, inequalities and transformation of the unequal wage structures both in South Africa and Germany. The Minimum Wage is implemented to prevent workers from earning very low wages. In both 3 countries the Minimum Wage is backed by the legislative framework. Processes to measure and enforce compliance are prevalent in both countries; however, the study found that it is very sophisticated to estimate the exact extent of non-compliance. The study further revealed that the effectiveness of Minimum Wages was seen to depend entirely on their policy design, implementation, and adoption as well as compliance measures. The success of the Minimum Wage solely depend on the compliance rate by employers, hence the study recommends that the New Minimum Wage legislation needs to ensure higher rates of compliance. The effective Minimum Wage should put measures in place to ensure that the compliance enforcement measures are practically implemented. A room still exists for both countries to mitigate wage inequalities that will benefit mostly the vulnerable employees. The study revealed that the NMW Commission needs to be capacitated with resources. A need of recruiting highly qualified inspectors was identified in order to strengthen the process of monitoring and ensuring compliance. The study further revealed that the appropriate Minimum Wage needs a collaborative participation of all stakeholders such as employers, the state, employees, trade unions, employer’s organization, bargaining councils, the member of public in order to achieve its professed mandate. , Thesis (LLM) -- Faculty of Law, Mercantile Law, 2021
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  • Date Issued: 2021-04

Normative Indicators for the Beery-Buktenica Developmental Test of Visual-Motor Integration on clinically unimpaired isiXhosa speaking adults with disadvantaged education

  • Authors: Kili, Ziphozakhe
  • Date: 2022-07
  • Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/27569 , vital:69316
  • Description: This study aimed to develop normative indicators for the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery VMI) for Xhosa speaking adults in the Eastern Cape with a grade 11 or 12 qualification from a previously disadvantaged educational background. Method: the sample size was 40 participants between the ages of 19 to 40 years old. The study used participants that had no cognitive impairments. This study used independent t-test analysis to compare test performance between the following categories: urban versus rural, males versus females, age group 19-29 versus 30-40. The Kruskall Wallis test was used to establish whether classroom size would have an impact on test performance. Results: This study revealed that there was a no statistical difference in performance between urban and rural participants, males and females, and classroom size. There was no statistical significance between the age categories 19-29 versus 30-40 on the visual perception and motor coordination supplementary tests. However, there was a statistical significance noted, between the age categories on the visual-motor integration test performance. Conclusions: it was concluded that the Beery VMI can be used with more confidence when assessing the Xhosa speaking population from disadvantaged educational backgrounds. The norms in this study cannot be generalized to other ethnic groups or populations. It was further recommended that more studies like this take place, and more norms are created for the South Africans using the Beery VMI. , Thesis (MSoc) -- Faculty of Social Sciences and Humanities, 2022
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  • Date Issued: 2022-07

Ocean structures and dynamics of two open bays on the eastern Agulhas Bank

  • Authors: Dlomo, Xolisa
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53607 , vital:45680
  • Description: Upwelling, bay-scale currents, fronts and mixing in Algoa Bay and St Francis Bay occur over both short and long time periods. These physical ocean dynamics drive the temporal and spatial distribution of nutrients in the bays, there by influencing primary and secondary production. Thermal gradients and fronts are driven by the wind and open ocean influences, such as the Agulhas Current, daily and seasonal variations in solar radiation, long and short period waves, air-sea fluxes, coastal trapped waves and terrestrial freshwater inflow. These phenomena are poorly understood along this part of the coastline and were the focus of this study. I investigated the dominant temperature scales of variability in both bays, to determine which isotherm is best suited to describe temperature fluctuations and thermocline spatiotemporal variability in and between the two bays. I investigated upwelling spatiotemporal variability in the two bays and tested whether upwelling occurs at the opposite sides of the bays with a change in wind direction. Thereafter studied the occurrence and drivers of winter upwelling events. The wind-driven current spatiotemporal variability and correlations were investigated at the extremities of the two bays. The daily, intra-seasonal and yearly variation in temperature structures in Algoa Bay and St. Francis Bay were mainly driven by the local winds, coastal topography, and bathymetry. The most suitable isotherm to describe thermal fluctuations and variability in Algoa Bay shallower sites was 16.5 °C and its mean depth was 16.2 m. The best isotherm for the deeper sites in Algoa Bay was 15.7 °C with a depth of 33.1 m. The average temperature and depth of the best isotherm to describe thermal fluctuations in St. Francis Bay for the shallower sites was15.80 °C and 16.83 m, and for the deeper sites it was 15.10 °C and 32.08 m. Algoa Bay showed an average cooling trend of -0.000172 °C per year, whereas in St. Francis Bay a warming average trend of 0.0188 °C per year was observed over the study period often and six years, respectively. The wind, Coriolis Effect and Ekman Transport were the main external forces that influenced upwelling throughout the year. Since the available mesoscale indices for upwelling intensity lack the resolution needed to characterize and compare inner-shelf upwelling regimes at small spatial scales, I developed a new local, quantitative index of thermal variability. Index calculations were based on hourly records of in site depth-averaged temperatures, measured at 6 sites in St. Francis Bay and at 8 sites in Algoa Bay. Using the Multivariate Upwelling Zone Index of Cooling (MUZIC) I found that Woody Cape and Blue Horizon Bay had the highest upwelling intensity in Algoa Bay and St. Francis Bay, respectively. The other sites were ordinated and ranked according to their upwelling rates and intensity. Evidence of wind-driven winter upwelling was found to be a common occurrence in both bays. There was no obvious current seasonality observed, however, strong spectral signals in the period of a weather band (4 –7 days) were present. Current structures were generally positively correlated with wind variations in both bays. Thus, when westerly/easterly winds blew the overall surface current direction was eastward/westward. I observed a pronounced current spatiotemporal variability that was driven by local winds. The Bird Island surface currents in Algoa Bay were strongly correlated at 0–lag day with the winds, however, in Cape Recife the strongest correlations were usually observed at 1–lag day highlighting the spatiotemporal influence of wind regimes on current structures in Algoa Bay. Bird Island current speeds were higher and had an obvious bimodal directional variation (south westward /north eastward) compared to Cape Recife currents, which generally had a slower current speed with a strong west-north westward direction. In St. Francis Bay, the Schoenmakerskop surface currents showed weak positive correlation with winds at 0–lag day, however, stronger negative correlations were observed at 4–lag days. The current surface speeds in Schoenmakerskop were the lowest and varied directionally between north-north eastward and south-south eastward. The basic data requirements (i.e. SST/ UTR and ADCP time series) and the simplicity of the calculations make these indices a useful tool to apply to a large number of sites nationally and internationally, and to examine the generality of community and population-level responses to physical forcing. , Thesis (PhD) -- Faculty of Science, Journalsim and Media Studies, 2021
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  • Date Issued: 2021-12

On the ideals and semimodules of commutative semirings

  • Authors: Olivier, Ruan
  • Date: 2021-04
  • Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/52782 , vital:44026
  • Description: Semirings are a generalisation of rings where additive inverses need not exist. In this dissertation, we focus on results of commutative semirings with non-zero identity. Many results that we study are analogous to results from commutative rings with non-zero identity. Properties which are unique to semirings are also investigated, such as semirings where all elements are additively idempotent. The notion of ideals is examined in the context of a semiring. Specifically, prime ideals, maximal ideals, k-ideals and partitioning ideals of semirings are considered. Additionally, the module over a ring is generalised to a semimodule over a semiring. The emphasis is on prime subsemimodules and multiplication semimodules. Lastly, invertible ideals of semirings are examined. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
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  • Date Issued: 2021-04

Optimising the uptake of [𝐈𝐫𝐂𝐥𝟔]𝟐− by a diammonium resin: HCl effect and resin performance

  • Authors: Ngayeka, Mbokazi Zizipho
  • Date: 2021-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/54089 , vital:46284
  • Description: The separation of [IrCl6]2- from [RhCl5(H2O)]2- by silica microparticles functionalized with 1,10-diamindecane (C10) and quaternized with 4-nitrobenzylchloride (NO2Benz) in various hydrochloric acid mediums was investigated by continuous column studies. The sorbent materials were synthesized using three different routes: Synthesis route 1 (NaI catalyzed synthesis of diammonium functionalized silica microparticles), Synthesis Route 2 (via silylazation of silica followed by functionalization) and Synthesis Route 3 (silane-based sorbent material). The functionalized sorbent materials were characterized by NMR, Microanalysis, SEM-EDS, FT-IR, TGA and BET surface area. The separation efficiency of the quaternary diammonium cations was investigated under dynamic flow adsorption conditions. Preliminary ICP-OES runs were done, at 6 M HCl, to assess which synthesis route gave the best performing sorbent material. [IrCl6]2- selectivity of the sorbent materials was achieved by washing with an HCl solution to remove unadsorbed metal species, then stripping off the [RhCl5(H2O)]2- with 0.05 M of sodium chlorate and the iridium species was eluted with a 20% HCl solution. From the preliminary ICP-OES, loading capacities were calculated, and it was observed that the three sorbent materials from synthesis route 2 (13.89 mg/g for (4) SSC10NO2Benz-A, 1.44 mg/g for (5) SSC10NO2Benz-HoA, and 1.0859 mg/g for (6) SSC10NO2Benz-DoA) showed the highest uptake of [IrCl6]2- and route 1 (1.89 mg/g for (1) SSC10NO2Benz-A, 1.25 mg/g for (2) SSC10NO2Benz-HoA and 0.99 mg/g for (3) SSC10NO2Benz-DoA ) and Route 3 (0.55 mg/g for (7) SC10-AI and 0.755 mg/g for (8) SC10-ACl) materials did not perform efficiently enough, thus were not used further for the HCl study. Within synthesis route 2, three sorbent materials were evaluated, which had varying quantities of the cation: SSC10NO2Benz-A (having a quantity previously used in our research and denoted A), SSC10NO2Benz-HoA (having a quantity Half of A) and SSC10NO2Benz-DoA (having a quantity double of A). SSC10NO2Benz-A showed the highest loading capacity than SSC10NO2Benz-HoA and SSC10NO2Benz-DoA; HCl studies were carried out using SSC10NO2Benz-A. HCl solution having different concentrations (5, 5.5 , 6 , 6.6 and 6.8 M) were used to prepare the metal solutions. This was done to assess which HCl concentration gave the best metal solution containing high amounts of [IrCl6]2- and [RhCl5(H2O)]2-, which would result in a more efficient separation. An auto titrator was used to standardize the HCl concentrations, and the metal ion chloride species solutions were determined by UV-Vis, and their concentrations were confirmed with ICP-OES. Column sorption of iridium and rhodium on SSC10NO2Benz-A using these HCl solutions was carried out, and loading capacities of [IrCl6]2- were obtained. The loading capacities of the 5 M, 5.5 M, 6 M, 6,6 M and 6.8 M HCl solutions for [IrCl6]2- were 2.64, 4.01, 13.89, 18.15 and 7.23 mg/g, respectively. The optimum separation conditions were thus determined by investigating effective parameters such as the method of synthesis, silica to cation ratio, HCl concentration and flow rate. This thesis presents quaternary diammonium sorbent materials that could be applied in feed solutions from ore processing for iridium recovery. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
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  • Date Issued: 2021-04

Optimization of liposomes for enhanced stability against degradation by gastrointestinal fluid content

  • Authors: Scholtz, Carla Chleo
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/54117 , vital:46305
  • Description: Motivation: Liposomes are nanoparticulate carriers consisting of a hydrophobic bilayer and a hydrophilic core. Their application as drug carrier systems arises from their unique physiochemical structure, biocompatibility and biodegradability. Their biphasic nature is significant in the delivery of peptide and protein drug molecules as it is thus able to encompass both hydrophobic and hydrophilic molecules. Liposomes are actively being used for drug delivery intravenously. These formulations have been successful in reducing side effects and improving therapeutic efficacy. However, the intravenous route poses many challenges and is not the preferred route of administration amongst patients. The oral route of administration is non-invasive, and administration is of ease, therefore it is the preferred route of administration amongst patients, especially those with complex medicine regimes. Problem: The gastrointestinal tract is a harsh environment. In order for liposomes to maintain their integrity during their course they require a level of stability against gastric and intestinal fluids and its associated constituents such as gastric and pancreatic enzymes, low pH and bile acid. Methodology: Based on recommendations extrapolated from literature, the incorporation of a bile salt, sodium glycocholate, into liposomes in conjunction with coating the surface with chitosan was selected as the optimization strategies to enhance the stability of liposomes against degradation in the gastrointestinal tract. Bilosomes with encapsulated calce in were produced using the thin-film hydration method and coated with chitosan. An in vitrocalce in release assay was conducted in simulated gastric and intestinal fluids which presented with in vivo conditions in terms of pH and enzymes and additional constituents such as a bile salt. Stability was determined by the extent of digestion within the simulated fluids with time. Results: Characterization results suggested that the addition of chitosan and sodium glycocholate to the liposomal formulation has significant effects on the physiochemical properties. The colloidal dispersions could not retain their stability during storage which was noticeable during HRTEM. Despite optimization of the liposomes, in vitro studies showed significant release in both simulated gastric and intestinal fluids, with majority release seen in the presence of pepsin and pancreatic, at low pH and in the presence of bile acid. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
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  • Date Issued: 2021-12

Optimizing herbicide-use for the killing of eucalypt stumps

  • Authors: Mavhungu, Tshilidzi
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53857 , vital:46023
  • Description: The South Africa (SA) forest industry relies on plantations of exotic forestry trees (Pinus, Acacia and Eucalyptus) to fulfil its timber requirements. With 52.0% of the afforested land in South Africa planted to various eucalypts and their hybrid combinations. Of the total area planted to eucalypts in SA, 75 000 ha is re-established annually by means of silvicultural regimes and operations matched to site productivity, desired end-product and method of regeneration. Unlike other commercially grown tree species, eucalypt species have the ability to coppice after felling. Coppicing is a common form of regeneration in South African forestry as it allows the plantation owner the option of a second timber rotation without replanting. However, if any factors affecting coppicing are compromised, and the site is to be replanted, then it is important to kill the stumps before replanting as rapid initial growth of the coppice shoots will require earlier control than that associated with normal weeding operations. Over time, various methods of woody plant control have been proposed and tested, with most of these making use of herbicides as opposed to the repeated manual removal of coppice regrowth. Globally, most industries subscribe to standards associated with sustainable production (economic, environmental and social) against which they are measured. Within SA, 80% of the forests are certified though either the Forest Stewardship Council (FSC) or International Standards Organisation (ISO) which recommend the identification and avoidance of ‘highly hazardous’ chemicals; the promotion of ‘non-chemical’ methods for pest management as an element of an integrated pest and vegetation management strategy; and the appropriate use of chemicals that are used. To test the current recommendations for killing eucalypt stumps to include other species, the potential of reducing herbicides used, and the influence of time after application on the survival of eucalypt stumps, two trials were initiated at Entabeni plantation (Venda, Limpopo) and one at Wilgeboom plantation (Bushbuckridge, Mpumalanga) between 2018 and 2020. Extending eucalypt cut-stump control practices: Most of the trial work on killing of eucalypts in SA has been conducted on Eucalyptus grandis, Eucalyptus camaldulensis or Eucalyptus macarthurii, with all grown on shorter pulpwood rotations. To extend current recommendation to include Eucalyptus cloeziana (grown on a longer rotation for poles), a trial was established in 2018 at Entabeni plantation (Limpopo Province) to quantify the interaction between Application method (basal-frill; cut-surface; foliar) and Herbicide (no herbicide applied; Roundup; Garlon; Roundup + Garlon) for the killing of 12 year-old stumps following harvesting. Assessments were carried out at 1, 3 and 6 months following application and included Stump survival, Stump quarter with coppice and Coppice heath. Relative to the control plots (100% survival), all herbicides tested were equally effective, 70–90% of the stumps killed. This study confirms previous research regarding the killing of eucalypt stumps. Roundup, Garlon or a combination of two, when applied according to label recommendations to a stump as a basal-frill or cut-surface application (within 30 minutes of felling) resulted in 70-90% of the stumps killed. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
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  • Date Issued: 2021-12

Participatory mapping of cultural ecosystem services in the Mountain Zebra National Park, South Africa

  • Authors: Mpapane, Nelsiwe Pertunia
  • Date: 2021-04
  • Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , Nature--Effect of human beings on--South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/52103 , vital:43432
  • Description: Cultural ecosystem services (CES) are an essential part of human well-being. CES characterize the intangible connections that people have with their surrounding environments, and act as vessels to facilitate the understanding of meaningful and respectful relationships between humans and nature, which are necessary for sustainability. However, CES render themselves as complex cultural dimensions that are difficult to connect to specific aspects of an ecosystem, or to measure and manage. Thus, a progressive approach is required for promoting effective management of CES within landscapes. This thesis endeavours to understand human─nature interactions in protected areas, the CES benefits that arise from such interactions, and the links of these to ecosystems, facilities or features within the landscape. Protected areas represent some of the last remaining intact ecological areas that support biodiversity conservation and human─nature experiences. Protected areas, such as the Mountain Zebra National Park, are therefore suitable study sites to cast light on: (a) how human─nature relationships manifest in parks, (b) which CES are experienced by visitors, (c) which landscape features are associated with CES benefits, (d) who visits the Park, and (e) how the delivery and/or accessibility of CES to visitors of the Park could be improved. My research involved qualitative and spatial elements as forms of enquiry over a period of six months of data collection. I used semi-structured interviews (n = 20) paired with a participatory mapping approach. Additionally, I performed a comparative analysis using a peer-reviewed paper that focused on the management perspectives of CES delivery, to seek out similarities and differences between management perspectives and actual visitor experiences. The findings of this study have outlined that the Mountain Zebra National Park offers significant benefits to visitors. Aesthetic, recreational, inspirational value and cultural heritage emerged as the most frequently mapped CES. The findings have also shown that CES benefits are widely distributed across the landscape, with a spatial correlation in hotspot areas. Moreover, amenities or built infrastructure such as picnic iii sites, camping areas and viewpoints within the Park, are crucial for strengthening social relationships among family and friends, as well as in aiding the delivery of CES. This study provides insights into the subjective and diverse ways that human─nature relationships translate into CES benefits. It also sheds light on the importance of adequate planning within protected areas, for the maximization of the benefits from CES to people without compromising the mandate of biodiversity conservation. This study also contributes to a growing body of evidence that documents human─nature interactions in, and non-material benefits acquired from, protected areas within South Africa. I further advocate for improved access, adequate infrastructure, awareness creation and strategies to attract the younger generation to the national parks of South Africa. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
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  • Date Issued: 2021-04

Perceptions of Nelson Mandela University social sciences post-graduate students on the decolonization of the social sciences modules

  • Authors: Manduluka, Lubabalo
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/54481 , vital:46603
  • Description: This research project is motivated by the students 2015-2016 higher education student protest that called for the decolonization of higher education institutions. It is widely accepted that for university module to serve students properly, it should be relevant to students it should be and must be localised. The research study considered the perceptions of post-graduate students on the decolonization of social sciences modules from the Nelson Mandela University. The objectives of the study are as follows: to investigate the perception of post-graduate students based within the School of Social Sciences on the decolonization of the social sciences modules at the Nelson Mandela University at South campus. To come up with recommendations with the view of addressing some to the challenges faced by tertiary institutions on decolonization of the social sciences modules at the Nelson Mandela University. The geographical area of the university is Eastern Cape, Port Elizabeth, Summerstrand, and the study was done on the south campus of the Nelson Mandela University. This study attempts to shed some light on the decolonization and Africanization of the modules through the lenses of post-graduate students. Literature is utilized to get a broader understanding of the concept of decolonization. The study also suggests how the university curriculum can be Africanized so that it can be more inclusive to African students and more relevant to African students. Interviews with post-graduate students are used as guideline to get a better understanding of how the modules affect them and the solutions to their concerns emerging from colonized modules. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
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  • Date Issued: 2021-12

Perceptions of small-scale vegetable farmers on drought mitigation strategies in the Amathole District Municipality of the Eastern Cape Province

  • Authors: Dingiswayo, Xolisile
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53676 , vital:45686
  • Description: The present study aimed to investigate perceptions of small-scale vegetable farmers on drought mitigation strategies in the Amathole District Municipality of the Eastern Cape Province. The research objective was to investigate what small-scale vegetable farmers’ perceptions and readiness are in terms of strategies to cope with drought conditions. The study was conducted within the Mbashe, Mnquma, Amahlathi and Great Kei local municipalities of the Eastern Cape. Primary data collection was conducted among 44 small-scale vegetable farmers of the Amathole municipal district. These are farmers who receive social support from the government, are registered with the Department of Rural Development and Agrarian Reform and contribute to the fight against food insecurity in the Amathole district. The primary data was also collected from 13 agricultural extension officers with high experience in advising small-scale farmers residing in the Amathole district. Data collection took place in various local municipalities under Amathole District Municipality, namely: Mbashe, Mnquma, Amahlathi and Great Kei. A multi-method approach was adopted in this study as an appropriate technique to create an improved quality of research which eliminates the deep-rooted bias to either qualitative or quantitative methods alone. A self-administered questionnaires with both closed and open-ended questions – one for the small-scale farmer survey and the second for the extension officer survey – was employed as data collection instrument. The demographic characteristics of small-scale vegetable farmers in the survey area indicated that the present majority of farmers are married male Xhosa farmers between the ages of 56 and 65 years old, with a secondary level of education. The majority of the farmers are typically resource-poor − which implies that the added menace of drought poses the risk that small-scale vegetable farming could decline to mere subsistence level or worse. Drought was found to be a major problem in Mbashe, Mnquma, Amahlathi and Great Kei local municipalities within the Amathole municipal district, with an acute impact on farmers’ production and generation of income. From the data, it emerged that farmers are not sufficiently informed about and do not receive specific training in drought mitigation strategies. Farmers rely on drought alleviation methods but there is a lack of adaptive strategies and timely, long-term ii state intervention. Being resource-poor, these small-scale producers are reliant on natural resources – notably water for irrigating crops. The study established further that there is neither the resources nor sufficient training by and involvement of the extension service. Farmers therefore rely on the use of drought coping mechanisms and drought mitigation techniques and on adapting their production systems. The information-sharing sessions recommended can assist in improving rural livelihoods and the productivity of small-scale vegetable farmers. The absence of engagement of youth in farming means that modern conservation and innovative farming techniques and systems are not implemented towards reducing the impacts of climate change − as well as revitalizing rural areas such Amathole. Access to education about drought, improved drought coping mechanisms and adaptive strategies should be created to facilitate an exchange of traditional and modern agricultural information. The development of infrastructure in rural communities and farming areas is another factor crucial to improving farming systems and operations in the Amathole municipal district. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
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  • Date Issued: 2021-12

Perceptions regarding corporate citizenship behaviour in Zimbabwe

  • Authors: Muzvidziwa, Itai
  • Date: 2015-03
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53396 , vital:45144
  • Description: Corporate Citizenship (CC) has risen as a conspicuous term in the literature dealing with the social role of business. Citizenship‟s focal point is the rights and responsibilities of all members of the community. CC can be defined as the extent to which organisations undertake the compulsory economic, legal, ethical, and discretionary responsibilities imposed on them by their stakeholders. CC recognises organisations as legal persons with certain rights and responsibilities as members of a community. The upsurge in undertaking acts of social responsibility illustrates that CC tends to be a strategic measurement that investors use to consciously align ethical concerns with publicly held organisations. In Zimbabwe, some organisations have made some progress towards CC - yet a long journey lies ahead in promoting CC by both the private sector and the Government of Zimbabwe. Against this background, the following research question was addressed in this study: What are the perceptions regarding CC behaviour in Zimbabwe? This study has been motivated by the knowledge gap on CC as a dynamic and contextual response to internal and external environmental pressures and the shift in community expectations concerning the roles, responsibilities and accountabilities of businesses in Zimbabwe. The main objective of this study was to investigate perceptions regarding corporate citizenship behaviour in Zimbabwe. A hypothetical model shows various factors that may influence perceptions regarding CC behaviour in Zimbabwe. Three independent variables (internal factors, external factors and personal factors) were identified as variables that may influence perceptions regarding CC behaviour. The mediating variable (perceptions regarding CC behaviour) was also identified as a variable that have potential to affect the dependent variables (organisational performance, competitiveness, image and sustainability). Furthermore, seven null-hypotheses were developed to test the relationship between the independent, mediating and dependent variables. All these variables were clearly defined and operationalised with various items obtained from measuring instruments used in other similar studies. , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Management Sciences, 2021
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  • Date Issued: 2015-03

Performance management system at a public development corporation: success factors and challenges

  • Authors: Saki, David Siphosethu
  • Date: 2021-04
  • Subjects: Gqeberha (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's , text
  • Identifier: http://hdl.handle.net/10948/52935 , vital:44733
  • Description: Public sector organisations often lack effectiveness in the implementation of an organisational strategy and seek out means of utilising a performance management system to ensure the productive implementation of its strategy (Auditor General South Africa, 2017). Therefore, it is important for organisations to utilise tools and techniques to ensure that the performance management system is efficiently implemented. Performance management is defined as a strategic and integrated approach aimed at delivering sustained success by using tools and techniques to improve the performance of people by developing the capabilities of teams and individual contributors (Armstrong, 2006). The main purpose of the study was to identify success factors that contributed to the effective implementation of a performance management system and then determine the extent to which these factors have been successfully incorporated in the performance management system at the CDC. The literature review was conducted, highlighting the process of performance management, tools and techniques, success factors and challenges in order to effectively implement a performance management system. In this study, a positive correlation between the PM purpose, success factors and tools revealed that the various success factors in relation to systems, resources, staff and measurement linked with the PM purpose. In addition, it was also revealed that the human resources component was considered as very important in driving an effective performance management system. , Thesis (MA) -- Faculty of Business and Economic Sciences, Human Resources Management, 2021
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  • Date Issued: 2021-04

Plastic particle characterization and concentrations found in the river and marine water environment of Algoa Bay, South Africa

  • Authors: Moss, Kerry-Leigh
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10948/53874 , vital:46025
  • Description: Only 12% of the world's published plastic research includes references to Africa despite it being a significant contributor to the global plastic waste and mismanagement problem (~88.5% of Africa's plastic waste is mismanaged). Ocean plastics are transported from land by rivers to the sea. However, source contextualization is complex. Many African rivers predominantly run alongside human settlements that host informal waste dumpsites. In this study a simple cost effective, easily deployed, consistent and replicable survey methodology was employed. The study quantified macro plastic in three rivers discharging into Algoa Bay, South Africa. The results indicated that industrial Swartkops and metropolitan Baakens Rivers both illustrate moderate plastic pollution (>3000 plastic particles/day), with the relatively natural Sundays River to showing minimal evidence of river macroplastic (<100 plastic particles/day). The types of plastic were noted using the RIMMEL app (premier African implementation), enabling proportional comparison of different plastic litter types to be completed. , Thesis (MSc) -- Faculty of Science, Oceanography Department,2021
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  • Date Issued: 2021-12

Possible futures for the African built environment towards 2050

  • Authors: Adendorff, Gillian Lorraine
  • Date: 2014-04
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Master's/Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53325 , vital:45136
  • Description: Purpose –The purpose of this thesis is to develop four scenarios for Africa’s built environment over the nextfortyyears: The ”Angel” or “Good Governance”Scenario,in which positive elements become a realisation for Africa’s built environment and are conjointly favourable; The “Dwarf” or “Uneven African Development”Scenario, in which key driving forces unfold inan uneven pattern, or have a differentiated impact on Africa’s built environment; The “Elf” or Bad Governance Scenario,in which less good governance prevails, but where a fortunate built environment and securemanagement allowsAfrica to become competitive and benefit from satisfactory economic growth;and The “Hobgoblin” or “Business and Governance as usual” Scenario,in which negative regional drivers of change corrode positive policies and initiatives in a manner which compounds the pre-existing threats of Africa’s built environment development.Design/Methodology/Approach –The goal of this thesis is not only to affirm what is already known and knowable regardingwhat is happening right now at the intersections of Africa and its built environment development, but also to explore the many ways in which environmental scanning and built environment development could co-involve,both push and inhibit each other,in the future. Thereafter, this thesis beginsto examine what possible paths may be implicatedfor Africa’s poor and vulnerable built environment. Scenario planning is a methodology designed to help researchers, organisations and even nations alike through this creative process. This thesis begins to identifydriversof change, and then combines these driversin different ways to create a set of scenarios regardinghow the future built environment of Africa could evolve.Practical implications –This thesis provides a useful insight regardingdrivers for change for Africa’s built environment,and how to anticipate these changes in the mostcurrentScenario planning.Originality/Value –This thesis addressesthe future of Africa’s built environment from a decision maker’s point of view over the next 40 years. , Thesis (PhD) -- Faculty of Engineering, the Built Environment and Technology, School of the Built Environment and Civil Engineering, 2021
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  • Date Issued: 2014-04

Post-apartheid geographies of studentification at Nelson Mandela University, Port Elizabeth, South Africa

  • Authors: Mzileni, Pedro Mihlali
  • Date: 2021-12
  • Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10948/53758 , vital:45759
  • Description: This study takes the concept of studentification from its British conception to the post-apartheid African city, Port Elizabeth (Gqeberha), where the Nelson Mandela University is situated. Studentification refers to the mass arrival of students in university cities and towns and the economic, infrastructural, geographic and sociopolitical changes that the settlements of these students make overtime to such cities and towns. For the case of Nelson Mandela University in Port Elizabeth, this study identified four major areas that are engulfed by studentification and sought to understand how this phenomenon takes shape in them. The study extends the existing terms and languages used to comprehend studentification by introducing a viewpoint of how it emerges in an African post-apartheid city. This is a city that has deindustrialised and has also experienced a capital flight out of its city centre since the 1970s. These declining economic indicators over decades have left the city to decay and experience high rates of unemployment, poverty and housing displacements. But, the post-1994 massification of the South African higher education system introduced new micro-economies for the city mainly through the emergence of student accommodation as a thriving business opportunity in the city in light of increased university enrolments. However, the economic injection brought by student accommodation in this city that has been deindustrialising remains minimal in having the necessary power to turnaround the city’s fortunes and transform the urban space towards a developmental path. This socioeconomic problem is also compounded by the presence of a weak arm of the state (particularly local government) that is unable to play an active role in driving capital flows to deliver tangible urban development. As a result, the university emerges as one of the active public actors in the renewal efforts of the city even though this is not its primary mandate. Thus, the process of studentification in this case takes place in a context defined by a declining higher education political economy and a weak city planning regime. As a result, these factors leave studentification to be vulnerable to being impacted by old colonial-apartheid structures of the city and the economic shortfalls of post-apartheid urban South Africa that have produced a precarious urban space where the private property market and the illicit economy have a stronger hand in determining the power relations that emerge in the city space. Studentification in this African city is expressed in four major geographies: (1) the Summerstrand suburb that is nearest to the University’s main urban campuses, (2) the Central CBD that has experienced capital flight and currently has tall buildings that are former offices of apartheid commerce which have been converted to student accommodation, (3) the deindustrialised and abandoned manufacturing sites at the North End margins of the city which have also been converted to student accommodation, and (4) the Zwide township, an underprivileged black community that is close to the former black Missionvale campus of the University – this is the furthest student accommodation area in the city. The study examines these student communities that emerge out of these four identified areas of the urban space and it also underscores the genre of the political, social, and economic relations of each of these four geographies and their interconnectedness. The study found that the South African post-apartheid city is characterised by an urban model and a university campus design that is a structural outcome of colonisation, apartheid spatial planning, and racial capitalism that still has continuing legacies today. As a result, these four geographies of studentification in the city are historical, racial and economic outcomes of urban power relations that originate from colonialism. Key defining features of studentification in each of these four areas were identified and analysed to illustrate that the South African account of studentification resembles the city’s apartheid legacy and these untransformed urban structures get further compounded by the country’s underfunded higher education massification strategy, its declining economic indicators and a weak state that has ‘soft’ planning and governance systems that are unable to decisively impact the trajectory of socioeconomic development in this university city. These intersecting forces translate into precarious day-to-day student life experiences and structural complications for the governance of the University and the city. These socioeconomic misfortunes also handicap the potential of the city to renew through a studentification economy. Henri Lefebvre’s Production of Space Theory was utilised to frame the study. Methodologically, the study utilised qualitative narrative interviews and document interpretation. This is the first doctoral thesis written about the concept of studentification in South Africa. , Thesis (PhD) -- Faculty of Humanities, The Department of Sociology and Anthropology, 2021
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  • Date Issued: 2021-12
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