Spatial modelling of accessibility to tuberculosis treatment: the case of Ngaka Modiri Molema District
- Authors: Ramotsongwa, Karabo Naome
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55435 , vital:52000
- Description: Accessibility to healthcare refers to the availability, or the provision of healthcare-byhealthcare professionals and stakeholders and individuals' ability to obtain care and treatment. It affects overall physical, social, and mental health; disease and disability prevention; detection and treatment of health conditions; standard of living; preventable death; and life expectancy, and it is crucial to the performance of health care systems around the world. If healthcare services are available and are in sufficient supply, people will be able to seek health care, and a population will have access to services. The leading cause of death globally is Tuberculosis (TB) and South Africa is amongst the top 5 countries most affected by TB. This is aggravated by high HIV/AIDS statistics. Children belowthe age of 4, between the ages of 4- 15, and women and men of working ages are highly affected by TB and it is the primary cause of death in these groups in the Ngaka Modiri Molema District. This study used study tools like Spatial Modelling, Geographic Information Systems and software like ArcGIS 10.5, TerrSet IDRISI 18.30, and secondary data from the North West Departmentof Health (Tier.net &DHIS) and also TB patients’ home addresses to investigate the accessibility of TB treatment in Ngaka Modiri Molema, in order to spatially visualize the distribution of a communicable disease like TB and public healthcare facilities in the Ngaka Modiri Molema (NMM) District and suggest optimum sites for hospital facilities. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Ramotsongwa, Karabo Naome
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55435 , vital:52000
- Description: Accessibility to healthcare refers to the availability, or the provision of healthcare-byhealthcare professionals and stakeholders and individuals' ability to obtain care and treatment. It affects overall physical, social, and mental health; disease and disability prevention; detection and treatment of health conditions; standard of living; preventable death; and life expectancy, and it is crucial to the performance of health care systems around the world. If healthcare services are available and are in sufficient supply, people will be able to seek health care, and a population will have access to services. The leading cause of death globally is Tuberculosis (TB) and South Africa is amongst the top 5 countries most affected by TB. This is aggravated by high HIV/AIDS statistics. Children belowthe age of 4, between the ages of 4- 15, and women and men of working ages are highly affected by TB and it is the primary cause of death in these groups in the Ngaka Modiri Molema District. This study used study tools like Spatial Modelling, Geographic Information Systems and software like ArcGIS 10.5, TerrSet IDRISI 18.30, and secondary data from the North West Departmentof Health (Tier.net &DHIS) and also TB patients’ home addresses to investigate the accessibility of TB treatment in Ngaka Modiri Molema, in order to spatially visualize the distribution of a communicable disease like TB and public healthcare facilities in the Ngaka Modiri Molema (NMM) District and suggest optimum sites for hospital facilities. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
State antiquity and early agricultural transition as deep economic roots in Africa
- Authors: Fani, Sisipho
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55487 , vital:52374
- Description: Growth economists identified that current failures and successes of economies can be traced far in their histories. The Unified Growth Model has been developed to analyse the process of development. Economic researchers have developed and identified ‘deep roots’ variables that elaborate modern growth, institutions and development. These variables include State Antiquity and Early agricultural transition. The study is an examination of the effects of State Antiquity and Early agricultural transition in the 54 African economies. The study examines these effects employing the following years: 1990, 1995, 2000, 2005, 2010, 2015, and 2020. The study employs econometric models namely, Ordinary Least Squares, Ridge and Lasso regularization models to examine the effects of these deep root variables. The study borrows baseline regressions from the works of Bockstette, Chanda and Putterman (2002), Putterman and Weil (2010) and Borcan, Olsson and Putterman (2018). This study, to the best of our knowledge, is the first to empirically examine the effects of State Antiquity and Early agricultural transition in Africa. The results of the study suggest that African economies that have low level of state antiquity experience a positive effect on modern economic growth and development whilst African economies with high levels of state antiquity experience negative effect on modern economic growth and development. The results also suggest that African economies that transition at a later stage toward agriculture experience a positive effect on modern economic growth and development. The implications of these findings indicate that state antiquity and early agricultural transition influence modern economic development only when states have reached a certain level. Countries that transitioned early towards agriculture experience a negative effect on modern economic growth and development depicting a reversal of fortune. The study recommends that the implementation of polices should corelate with the state experience of the specific economy. , Thesis (M.Com.) -- Faculty of Business and Economic Sciences, School of Economics, Development & Tourism, 2022
- Full Text:
- Authors: Fani, Sisipho
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55487 , vital:52374
- Description: Growth economists identified that current failures and successes of economies can be traced far in their histories. The Unified Growth Model has been developed to analyse the process of development. Economic researchers have developed and identified ‘deep roots’ variables that elaborate modern growth, institutions and development. These variables include State Antiquity and Early agricultural transition. The study is an examination of the effects of State Antiquity and Early agricultural transition in the 54 African economies. The study examines these effects employing the following years: 1990, 1995, 2000, 2005, 2010, 2015, and 2020. The study employs econometric models namely, Ordinary Least Squares, Ridge and Lasso regularization models to examine the effects of these deep root variables. The study borrows baseline regressions from the works of Bockstette, Chanda and Putterman (2002), Putterman and Weil (2010) and Borcan, Olsson and Putterman (2018). This study, to the best of our knowledge, is the first to empirically examine the effects of State Antiquity and Early agricultural transition in Africa. The results of the study suggest that African economies that have low level of state antiquity experience a positive effect on modern economic growth and development whilst African economies with high levels of state antiquity experience negative effect on modern economic growth and development. The results also suggest that African economies that transition at a later stage toward agriculture experience a positive effect on modern economic growth and development. The implications of these findings indicate that state antiquity and early agricultural transition influence modern economic development only when states have reached a certain level. Countries that transitioned early towards agriculture experience a negative effect on modern economic growth and development depicting a reversal of fortune. The study recommends that the implementation of polices should corelate with the state experience of the specific economy. , Thesis (M.Com.) -- Faculty of Business and Economic Sciences, School of Economics, Development & Tourism, 2022
- Full Text:
The application of the prescription act in labour disputes
- Authors: Mncanca, Siyamthanda
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55498 , vital:52375
- Description: It is inevitable that in an employment relationship grievances and conflicts may emerge.1 This is attested to by the large volume of 193 732 disputes that were referred to the Commission for Conciliation, Mediation and Arbitration (CCMA) during the 2018/19 financial year.2 In the event where an employee is dismissed from work and he decides to challenge the dismissal, section 191 of the Labour Relations Act (LRA) grants the employee a right to refer the matter to the CCMA for conciliation or arbitration.3 The purpose of referring the disputes to the CCMA is to support an establishment of a voluntary, free of charge and expeditious mechanisms for labour disputes settlement and allow parties to resolve their disputes through a consensus based process before taking the route of a court process.4 There are time frames that are provided for the referral of disputes to the CCMA. Section 191 determines these time frames by stating that an employee must refer their alleged unfair dismissal to the CCMA within 30 days or 90 days when a dispute relates to an unfair labour practice in accordance with section 191(1)(b)(ii) of the LRA.5 The rationale behind these time frames was outlined in the Constitutional Court (CC) judgement of Toyota SA Motors (Pty) Ltd v CCMA,6 as a means to bring about the expeditious resolution of labour disputes which by their nature, require speedy resolution. , Thesis (L.L.M.) -- Faculty of Law, Mercantile Law, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Mncanca, Siyamthanda
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55498 , vital:52375
- Description: It is inevitable that in an employment relationship grievances and conflicts may emerge.1 This is attested to by the large volume of 193 732 disputes that were referred to the Commission for Conciliation, Mediation and Arbitration (CCMA) during the 2018/19 financial year.2 In the event where an employee is dismissed from work and he decides to challenge the dismissal, section 191 of the Labour Relations Act (LRA) grants the employee a right to refer the matter to the CCMA for conciliation or arbitration.3 The purpose of referring the disputes to the CCMA is to support an establishment of a voluntary, free of charge and expeditious mechanisms for labour disputes settlement and allow parties to resolve their disputes through a consensus based process before taking the route of a court process.4 There are time frames that are provided for the referral of disputes to the CCMA. Section 191 determines these time frames by stating that an employee must refer their alleged unfair dismissal to the CCMA within 30 days or 90 days when a dispute relates to an unfair labour practice in accordance with section 191(1)(b)(ii) of the LRA.5 The rationale behind these time frames was outlined in the Constitutional Court (CC) judgement of Toyota SA Motors (Pty) Ltd v CCMA,6 as a means to bring about the expeditious resolution of labour disputes which by their nature, require speedy resolution. , Thesis (L.L.M.) -- Faculty of Law, Mercantile Law, 2022
- Full Text:
- Date Issued: 2022-04
Evaluation of the extent of the public programming by Eastern Cape Provincial Archives and Records Services
- Tshebi, Siyathemba Mboneleli https://orcid.org/0000-0003-2833-9842
- Authors: Tshebi, Siyathemba Mboneleli https://orcid.org/0000-0003-2833-9842
- Date: 2022
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27663 , vital:69381
- Description: Public programming initiatives are an integral part of archival operations worldwide as they support the greater use of archival records by attracting prospective users and sponsors. Public programming comprises a sequence of strategies for publicizing and marketing archives to the public, which are crucial in archival operations as they promote better use of archives and records. South African National Archives and Records. Services depends on provisions of the National Archives of South Africa Act of 1996 in its strive to promote access and use of archives as sources of information. . unknown and therefore not used to their maximal utility value, likely due to low-key and ineffective archival public programming initiatives. Consequently, the primary purpose of this research study was to evaluate the extent of public programming strategies used by the Eastern Cape Provincial Archives and Records Services (EAPARS). The study used a mixed-method, embracing qualitative and quantitative research approaches. As an integrated record-keeping framework, Record Continuum was used as a theoretical framework to guide the study. Sixteen copies of questionnaire were distributed among staff and users ECPARS. The research uncovered that ECPARS does not have specific regulations and policies on public programming, but relies on the more general provisions of the Provincial Archives and Records Services Act of 1996 as a guiding instrument in executing its public programming operations. The study further revealed various factors, such as the limited budget and inadequate staff, as key hindering factors in the smooth execution of archival public programming plans by ECPARS. The study recommends a review and update by ECPARS of how it can specifically effectively implement the provisions of the 1996 Act to the modern ways of taking public archives to the people. The research also recommends that ECPARS engage additional staff or outsourced services to strengthen its the public programming of its archival resources and services workforce for Eastern Cape Provincial Archives and Records. The study concludes that improved financial resources, use of ICTs, and coherent policy framework, and public awareness creation and education can facilitate better to acquire, widen access to use of its archives. Keyword , Thesis (MLIS) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022
- Authors: Tshebi, Siyathemba Mboneleli https://orcid.org/0000-0003-2833-9842
- Date: 2022
- Subjects: Grahamstown (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/27663 , vital:69381
- Description: Public programming initiatives are an integral part of archival operations worldwide as they support the greater use of archival records by attracting prospective users and sponsors. Public programming comprises a sequence of strategies for publicizing and marketing archives to the public, which are crucial in archival operations as they promote better use of archives and records. South African National Archives and Records. Services depends on provisions of the National Archives of South Africa Act of 1996 in its strive to promote access and use of archives as sources of information. . unknown and therefore not used to their maximal utility value, likely due to low-key and ineffective archival public programming initiatives. Consequently, the primary purpose of this research study was to evaluate the extent of public programming strategies used by the Eastern Cape Provincial Archives and Records Services (EAPARS). The study used a mixed-method, embracing qualitative and quantitative research approaches. As an integrated record-keeping framework, Record Continuum was used as a theoretical framework to guide the study. Sixteen copies of questionnaire were distributed among staff and users ECPARS. The research uncovered that ECPARS does not have specific regulations and policies on public programming, but relies on the more general provisions of the Provincial Archives and Records Services Act of 1996 as a guiding instrument in executing its public programming operations. The study further revealed various factors, such as the limited budget and inadequate staff, as key hindering factors in the smooth execution of archival public programming plans by ECPARS. The study recommends a review and update by ECPARS of how it can specifically effectively implement the provisions of the 1996 Act to the modern ways of taking public archives to the people. The research also recommends that ECPARS engage additional staff or outsourced services to strengthen its the public programming of its archival resources and services workforce for Eastern Cape Provincial Archives and Records. The study concludes that improved financial resources, use of ICTs, and coherent policy framework, and public awareness creation and education can facilitate better to acquire, widen access to use of its archives. Keyword , Thesis (MLIS) -- Faculty of Social Sciences and Humanities, 2022
- Full Text:
- Date Issued: 2022
A data-driven decision-making model for the third-party logistics industry in Africa
- Authors: Moyo, Faith
- 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/10948/53875 , vital:46022
- Description: Third-party logistics (3PL) providers have continued to be key players in the supply chain network and have witnessed a growth in the usage of information technology. This growth has enhanced the volume of structured and unstructured data that is collected at a high velocity, and is of rich variety, sometimes described as “Big Data”. Leaders in the 3PL industry are constantly seeking to effectively and efficiently mature their abilities to exploit this data to gain business value through data-driven decision-making (DDDM). DDDM helps the leaders to reduce the reliance they place on observations and intuition to make crucial business decisions in a volatile business environment. The aim of this research was to develop a prescriptive model for DDDM in 3PLs. The model consists of iterative elements that prescribe guidelines to decision-makers in the 3PL industry on how to adopt DDDM. A literature review of existing theoretical frameworks and models for DDDM was conducted to determine the extent to which they contribute towards DDDM for 3PLs. The Design-Science Research Methodology (DSRM) was followed to address the aim of the research and applied to pragmatically and iteratively develop and evaluate the artefact (the model for DDDM) in the real-world context of a 3PL. The literature findings revealed that the challenges with DDDM in organisations include three main categories of challenges related to data quality, data management, vision and capabilities. Once the challenges with DDDM were established, a prescriptive model was designed and developed for DDDM in 3PLs. Qualitative data was collected from semi-structured interviews to gain an understanding of the problems and possible solutions in the real-world context of 3PLs. An As-Is Analysis in the real-world case 3PL company confirmed the challenges identified in literature, and that data is still used in the 3PL company for descriptive and diagnostic analytics to aid with the decision-making processes. This highlights that there is still room for maturity into using data for predictive and prescriptive analytics that will, in turn, improve the decision-making process. An improved second version of the model was demonstrated to the participants (the targeted users), who had the opportunity to evaluate the model. The findings revealed that the model provided clear guidelines on how to make data-driven decisions and that the feedback loop and the data culture aspects highlighted in the design were some of the important features of the model. Some improvements were suggested by participants. A field study of three data analytics tools was conducted to identify the advantages and disadvantages of each as well as to highlight the status of DDDM at the real-world case 3PL. The limitations of the second version of the model, together with the recommendations from the participants were used to inform the improved and revised third version of the model. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Moyo, Faith
- 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/10948/53875 , vital:46022
- Description: Third-party logistics (3PL) providers have continued to be key players in the supply chain network and have witnessed a growth in the usage of information technology. This growth has enhanced the volume of structured and unstructured data that is collected at a high velocity, and is of rich variety, sometimes described as “Big Data”. Leaders in the 3PL industry are constantly seeking to effectively and efficiently mature their abilities to exploit this data to gain business value through data-driven decision-making (DDDM). DDDM helps the leaders to reduce the reliance they place on observations and intuition to make crucial business decisions in a volatile business environment. The aim of this research was to develop a prescriptive model for DDDM in 3PLs. The model consists of iterative elements that prescribe guidelines to decision-makers in the 3PL industry on how to adopt DDDM. A literature review of existing theoretical frameworks and models for DDDM was conducted to determine the extent to which they contribute towards DDDM for 3PLs. The Design-Science Research Methodology (DSRM) was followed to address the aim of the research and applied to pragmatically and iteratively develop and evaluate the artefact (the model for DDDM) in the real-world context of a 3PL. The literature findings revealed that the challenges with DDDM in organisations include three main categories of challenges related to data quality, data management, vision and capabilities. Once the challenges with DDDM were established, a prescriptive model was designed and developed for DDDM in 3PLs. Qualitative data was collected from semi-structured interviews to gain an understanding of the problems and possible solutions in the real-world context of 3PLs. An As-Is Analysis in the real-world case 3PL company confirmed the challenges identified in literature, and that data is still used in the 3PL company for descriptive and diagnostic analytics to aid with the decision-making processes. This highlights that there is still room for maturity into using data for predictive and prescriptive analytics that will, in turn, improve the decision-making process. An improved second version of the model was demonstrated to the participants (the targeted users), who had the opportunity to evaluate the model. The findings revealed that the model provided clear guidelines on how to make data-driven decisions and that the feedback loop and the data culture aspects highlighted in the design were some of the important features of the model. Some improvements were suggested by participants. A field study of three data analytics tools was conducted to identify the advantages and disadvantages of each as well as to highlight the status of DDDM at the real-world case 3PL. The limitations of the second version of the model, together with the recommendations from the participants were used to inform the improved and revised third version of the model. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
A spatial assessment of riparian vegetation density and implications for streambank erosion in relation to land tenure in the Mgwalana Catchment, Eastern Cape Province, South Africa
- Authors: Maxama, Asakhile
- 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/10948/53864 , vital:46026
- Description: Riparian vegetation provides an array of various ecosystem functions and has significantly shaped the conditions of catchments. It has strong controls on fluvial geomorphology and erosion processes. The Mgwalana catchment has been intensively studied over the years and the current environmental condition of the study has been linked to land use history. The catchment has been subjected to land use/cover changes (LUCC) over the years. However, spatial variations in riparian vegetation, their implications for stream bank stability and the contribution of land tenure systems to stream channel degradation are poorly understood. The study sought to assess the implications of the spatial variations in riparian vegetation density for stream bank erosion in relation to land tenure on a catchment scale. Land tenure units comprising the catchment of study are traditional and betterment villages (communal lands), and former white commercial farms. A three-pronged approach using GIS and remote sensing, field investigations and laboratory procedures for soil analysis was employed in this study. Variations of riparian vegetation density in the catchment were mapped using ArcGIS for the two land tenure units to assess the spatial variations of riparian density along stream reaches and to determine the spatial relationship between land tenure units and riparian vegetation diminution. Other mapped shape files include sediment accumulation zones to analyse the spatial relationship between riparian vegetation density and sediment sinks. LUCC classification and analysis of the Normalized Difference Vegetation Index (NDVI) were carried out in IDRISI Selva, using Landsat 8 TM imagery of 2018 to represent the current spatial riparian vegetation variations in the catchment. Field investigations were conducted to determine the coupling among hillslope gully erosion, riparian vegetation density and sink areas; and to assess physical characteristics of soil. This would permit an assessment of the implications of riparian vegetation for stream bank erosion and sediment accumulation within the tenure units. Soil samples were taken from scantily and densely vegetated stream reaches, as well as measurements of channel widths and depths. Analyses of soil physical properties viz; grain size distribution, bulk density, soil texture and aggregate stability were done. Results demonstrated that a sparse riparian vegetation distribution was consistent with the communal villages, confined to the upper catchment area. Dense riparian vegetation distribution was consistent with former commercial farms in the lower catchment area. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Maxama, Asakhile
- 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/10948/53864 , vital:46026
- Description: Riparian vegetation provides an array of various ecosystem functions and has significantly shaped the conditions of catchments. It has strong controls on fluvial geomorphology and erosion processes. The Mgwalana catchment has been intensively studied over the years and the current environmental condition of the study has been linked to land use history. The catchment has been subjected to land use/cover changes (LUCC) over the years. However, spatial variations in riparian vegetation, their implications for stream bank stability and the contribution of land tenure systems to stream channel degradation are poorly understood. The study sought to assess the implications of the spatial variations in riparian vegetation density for stream bank erosion in relation to land tenure on a catchment scale. Land tenure units comprising the catchment of study are traditional and betterment villages (communal lands), and former white commercial farms. A three-pronged approach using GIS and remote sensing, field investigations and laboratory procedures for soil analysis was employed in this study. Variations of riparian vegetation density in the catchment were mapped using ArcGIS for the two land tenure units to assess the spatial variations of riparian density along stream reaches and to determine the spatial relationship between land tenure units and riparian vegetation diminution. Other mapped shape files include sediment accumulation zones to analyse the spatial relationship between riparian vegetation density and sediment sinks. LUCC classification and analysis of the Normalized Difference Vegetation Index (NDVI) were carried out in IDRISI Selva, using Landsat 8 TM imagery of 2018 to represent the current spatial riparian vegetation variations in the catchment. Field investigations were conducted to determine the coupling among hillslope gully erosion, riparian vegetation density and sink areas; and to assess physical characteristics of soil. This would permit an assessment of the implications of riparian vegetation for stream bank erosion and sediment accumulation within the tenure units. Soil samples were taken from scantily and densely vegetated stream reaches, as well as measurements of channel widths and depths. Analyses of soil physical properties viz; grain size distribution, bulk density, soil texture and aggregate stability were done. Results demonstrated that a sparse riparian vegetation distribution was consistent with the communal villages, confined to the upper catchment area. Dense riparian vegetation distribution was consistent with former commercial farms in the lower catchment area. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2021
- Full Text:
- Date Issued: 2021-12
A value alignment smart city stakeholder model
- Van der Hoogen, Anthea Vivian
- Authors: Van der Hoogen, Anthea Vivian
- 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/10948/54129 , vital:46309
- Description: The concept of a Smart City has evolved over the last three decades and has attracted the increasing interest of the scientific research community. Unfortunately, many Smart City projects and initiatives do not provide the value expected by all the stakeholders. Many of the reasons for this relate to a lack of data management, data integration, data access and stakeholder participation. People are an integral part of any city’s ecosystem, and the Smart City concept was introduced to address the challenges of an ever-growing global population leading to the risk of depletion of economic, environmental and social resources. The problem addressed in this study is based on the challenges preventing the creation of the value of smart cities or stakeholders. Limited research has been published on the status of Smart City initiatives or on the impact of various success factors on the potential value creation for stakeholders including citizens. Studies on initiatives in developing countries, such as South Africa are even less. Whilst some challenges and constraints related to smart cities in Africa have been reported, there are no studies reporting on initiatives across the data value chain that consider all types of stakeholders, nor the impact of these initiatives. This study addressed this gap in research and designed a theoretical Value Alignment Smart City Stakeholder (VASCS) Model based on a Systematic Literature Review and a review of related theories. The model has important components that should form part of any Smart City project or Smart City initiative. These five main components are: 1) nine Smart City dimensions with related success factors; 2) four stakeholder roles (enablers, providers, utilisers and users); 3) the data value chain; and 4) the five phases of stakeholder benefits/value realisation that can be linked to; 5) stakeholder value alignment. This study applied the VASCS Model to Smart City initiatives in two case studies in the Eastern Cape Province of South Africa, which were the Nelson Mandela Bay and Buffalo City to investigate and understand the status of such initiatives and the alignment of value thereof. The stakeholder interviews were conducted in two rounds with various stakeholders of Smart City initiatives, referred to as cases in the two case studies. An expert review of the VASCS Model was conducted with eight experts in the field of Information Systems and Smart Cities. The findings of this review served to confirm the components of the model, with only minor improvements recommended. It was confirmed that all of the components need to be considered in planning Smart City projects. The first round consisted of six interviews with enablers and providers and the second round consisted of 22 interviews with users, utilisers and citizens. The interviews investigated the value and impact experienced by stakeholders of these initiatives, with a particular focus on the users, utilisers and citizens of the cases. The interview data was transcribed and qualitatively analysed by using Atlas.tiand Excel. The data was analysed according to the Technological, Organisational and Environmental theory constructs and other identified themes. The interview analysis findings revealed several drivers for these initiatives, which were primarily cost reduction, integration and quality assurance. The results also highlighted access to resources, such as technical skills as a challenge. Another challenge identified was connectivity related to access to data and the digital and physical divide that can impact decision making. The main benefits of Smart City initiatives highlighted were the provision of infrastructure, education and training and digitalisation. The theoretical contribution of this study is the VASCS Model, which can assist other researchers and practitioners with knowledge of the factors, drivers, challenges and value obtained in Smart City initiatives. The model has two supplementary components: A Stakeholder Classification Model and a Smart City Success Factor Evaluation Template. The practical contribution of this study is the potential use of the VASCS Model by practitioners, city management, researchers and other stakeholders, who can use the model, with the related model and template for planning and evaluating Smart City initiatives. The model can be used to classify the digital activities according to a Smart City’s success factors while evaluating the value created by these activities. The impact of these initiatives can then be assessed through value realisation and alignment for stakeholders. The scientific contribution is the adoption of the model to the cases in the Eastern Cape. To reveal in depth, rich, interview findings that provide important lessons learnt relating to the value created for the stakeholders and the addition of these findings to the body of knowledge. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Van der Hoogen, Anthea Vivian
- 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/10948/54129 , vital:46309
- Description: The concept of a Smart City has evolved over the last three decades and has attracted the increasing interest of the scientific research community. Unfortunately, many Smart City projects and initiatives do not provide the value expected by all the stakeholders. Many of the reasons for this relate to a lack of data management, data integration, data access and stakeholder participation. People are an integral part of any city’s ecosystem, and the Smart City concept was introduced to address the challenges of an ever-growing global population leading to the risk of depletion of economic, environmental and social resources. The problem addressed in this study is based on the challenges preventing the creation of the value of smart cities or stakeholders. Limited research has been published on the status of Smart City initiatives or on the impact of various success factors on the potential value creation for stakeholders including citizens. Studies on initiatives in developing countries, such as South Africa are even less. Whilst some challenges and constraints related to smart cities in Africa have been reported, there are no studies reporting on initiatives across the data value chain that consider all types of stakeholders, nor the impact of these initiatives. This study addressed this gap in research and designed a theoretical Value Alignment Smart City Stakeholder (VASCS) Model based on a Systematic Literature Review and a review of related theories. The model has important components that should form part of any Smart City project or Smart City initiative. These five main components are: 1) nine Smart City dimensions with related success factors; 2) four stakeholder roles (enablers, providers, utilisers and users); 3) the data value chain; and 4) the five phases of stakeholder benefits/value realisation that can be linked to; 5) stakeholder value alignment. This study applied the VASCS Model to Smart City initiatives in two case studies in the Eastern Cape Province of South Africa, which were the Nelson Mandela Bay and Buffalo City to investigate and understand the status of such initiatives and the alignment of value thereof. The stakeholder interviews were conducted in two rounds with various stakeholders of Smart City initiatives, referred to as cases in the two case studies. An expert review of the VASCS Model was conducted with eight experts in the field of Information Systems and Smart Cities. The findings of this review served to confirm the components of the model, with only minor improvements recommended. It was confirmed that all of the components need to be considered in planning Smart City projects. The first round consisted of six interviews with enablers and providers and the second round consisted of 22 interviews with users, utilisers and citizens. The interviews investigated the value and impact experienced by stakeholders of these initiatives, with a particular focus on the users, utilisers and citizens of the cases. The interview data was transcribed and qualitatively analysed by using Atlas.tiand Excel. The data was analysed according to the Technological, Organisational and Environmental theory constructs and other identified themes. The interview analysis findings revealed several drivers for these initiatives, which were primarily cost reduction, integration and quality assurance. The results also highlighted access to resources, such as technical skills as a challenge. Another challenge identified was connectivity related to access to data and the digital and physical divide that can impact decision making. The main benefits of Smart City initiatives highlighted were the provision of infrastructure, education and training and digitalisation. The theoretical contribution of this study is the VASCS Model, which can assist other researchers and practitioners with knowledge of the factors, drivers, challenges and value obtained in Smart City initiatives. The model has two supplementary components: A Stakeholder Classification Model and a Smart City Success Factor Evaluation Template. The practical contribution of this study is the potential use of the VASCS Model by practitioners, city management, researchers and other stakeholders, who can use the model, with the related model and template for planning and evaluating Smart City initiatives. The model can be used to classify the digital activities according to a Smart City’s success factors while evaluating the value created by these activities. The impact of these initiatives can then be assessed through value realisation and alignment for stakeholders. The scientific contribution is the adoption of the model to the cases in the Eastern Cape. To reveal in depth, rich, interview findings that provide important lessons learnt relating to the value created for the stakeholders and the addition of these findings to the body of knowledge. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
Administrative justice and the implementation of the reconstruction and development program in Berlin Town, Eastern Cape
- Authors: Makie, Fundiswa
- 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/10948/54460 , vital:46577
- Description: Housing delivery in South Africa is a crucial and topical issue affecting many citizens. The primary objective of the study was to determine the role of administrative justice in the implementation of the Reconstructive and Development Programme (RDP) in Berlin Town, in the province of the Eastern Cape in South Africa. In addition, the aim of this study was to explore the challenges of RDP housing in the study area, as a way of probing whether housing needs were being met. The study was conducted using a qualitative research methodology in gathering data from Berlin Town residents, Buffalo City Metropolitan Municipality staff and Berlin Town councillors. The data analysis revealed that respondents affirmed the importance of administrative justice and the effective implementation of the RDP with regard to housing. Based on the findings of the study, the researcher recommends that the Buffalo City Metropolitan Municipality prioritise the full implementation of the Integrated Development Plan (IDP) in dealing with the housing backlog and challenges in Berlin Town. Moreover, the findings of this study revealed that it is possible to highlight specific recommendations that can be used by various other local municipalities. Thus, the research study showed that efficient local municipal operations have a direct impact on the delivery of RDP houses. Relating to ethical considerations, the researcher ensured that all the requirements for credible research were met throughout the study. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Makie, Fundiswa
- 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/10948/54460 , vital:46577
- Description: Housing delivery in South Africa is a crucial and topical issue affecting many citizens. The primary objective of the study was to determine the role of administrative justice in the implementation of the Reconstructive and Development Programme (RDP) in Berlin Town, in the province of the Eastern Cape in South Africa. In addition, the aim of this study was to explore the challenges of RDP housing in the study area, as a way of probing whether housing needs were being met. The study was conducted using a qualitative research methodology in gathering data from Berlin Town residents, Buffalo City Metropolitan Municipality staff and Berlin Town councillors. The data analysis revealed that respondents affirmed the importance of administrative justice and the effective implementation of the RDP with regard to housing. Based on the findings of the study, the researcher recommends that the Buffalo City Metropolitan Municipality prioritise the full implementation of the Integrated Development Plan (IDP) in dealing with the housing backlog and challenges in Berlin Town. Moreover, the findings of this study revealed that it is possible to highlight specific recommendations that can be used by various other local municipalities. Thus, the research study showed that efficient local municipal operations have a direct impact on the delivery of RDP houses. Relating to ethical considerations, the researcher ensured that all the requirements for credible research were met throughout the study. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text:
- Date Issued: 2021-12
Assessing service delivery protests in the Nelson Mandela Bay Municipality: the case of Walmer Township
- Authors: Mdanyana, Esethu
- 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/10948/54492 , vital:46609
- Description: In many South Africa’s areas, citizen’s frustration with poor or slow service delivery has resulted in a surge of service delivery protests. Some of these service delivery protests are violent in nature, resulting in the damage of public and private property. Therefore, it is imperative to scrutinize service delivery protests. The South African constitution states that municipalities have the responsibility to make sure that all citizens are provided with services to satisfy their basic needs. These services include water supply, sewage collection and disposal electricity, gas supply health services, roads, storm water drainage, street lighting, municipal parks and recreation. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Mdanyana, Esethu
- 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/10948/54492 , vital:46609
- Description: In many South Africa’s areas, citizen’s frustration with poor or slow service delivery has resulted in a surge of service delivery protests. Some of these service delivery protests are violent in nature, resulting in the damage of public and private property. Therefore, it is imperative to scrutinize service delivery protests. The South African constitution states that municipalities have the responsibility to make sure that all citizens are provided with services to satisfy their basic needs. These services include water supply, sewage collection and disposal electricity, gas supply health services, roads, storm water drainage, street lighting, municipal parks and recreation. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
Effect of coal and microalgae biomass co-firing on CO2, SO2 and NOx emissions: An experimental evaluation
- Authors: Magida, Nokuthula Ethel
- 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/10948/53817 , vital:45984
- Description: There is increasingly stringent legislation on the environmental impact of energy production from coal combustion, and this has led to growing pressure to reduce the emission of greenhouse gases (GHGs). Thus, there is a significant need to develop and implement clean coal combustion technologies that would reduce the environmental gas pollutants. For power generation, the co-firing of biomass fuels at conventional coal-fired power stations is recognised as one of the low-cost, low-risk options to achieve significant reductions in GHG emissions. When coal is co-utilized with biomass there is added attractiveness because the biomass is CO2 neutral, and there is interest in using waste biomass and microalgae. Thus, the co-combustion of coal and biomass for energy production results in pollutant reduction, especially in the emissions of NOx, SOx, volatile organic compounds and polyaromatic hydrocarbons. The synergistic activity observed for toxic organic emissions is not well understood and is thought to involve chemical interaction between the volatiles from each fuel coupled with possible catalytic activity from the inorganic constituents of the fuels. The characterization of co-firing products and gases emitted from coal and microalgae (particularly the Scenedesmus strain) co-combustion has received limited attention. Therefore, this study seeks to understand possible interactions occurring during co-combustion of coal and Scenedesmus microalgae (Coalgae®). Additionally, the study aims to determine the effect of co-firing coal and Scenedesmus microalgae on CO2, SO2 and NOx emissions. The term “Coalgae®” refers to the mixture of coal and microalgae biomass. The study looks at physico-thermal characteristics as well as CO2, SO2 and NOx emissions of various coal-microalgae blending ratios by mass; 100:0 (coal), 95:5 (Coalgae® 5%), 90:10 (Coalgae® 10%), 85:15 (Coalgae® 15%) and 80:20 (Coalgae® 20%). Characterization techniques carried out included proximate and ultimate analyses, Fourier-transform infrared (FT-IR) and Scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDS). For combustion studies two techniques were applied. Low heating rate was obtained through a Thermogravimetric-Mass spectrometer analysis (TG-MS). Other combustion experiments were performed on the five lumpy fuels (coal and Coalgae® 5% - 20%) exposed to the flame in a fixed-bed combustion reactor. The emission concentrations of CO2 (%), NOx (ppm) and SO2 (ppm) of coal and Coalgae® blends were measured during the combustion of the five materials using a Lancom 4 portable flue gas analyser. The mass reduction (g) and temperature (°C) at the reactor exit were recorded during the combustion tests to compare the combustion behaviour of the four mixtures to that of raw coal. TG-DTG curves of coal and microalgae confirmed that the combustion behaviour of these materials was different. Coal showed one reaction during the combustion process, while microalgae and the Coalgae® blends showed three reactions. A significant reduction in activation energies of 160.4 kJ/mol, 159.6 kJ/mol, 151.3 kJ/mol, and 134.2 kJ/mol for Coalgae® 5% - Coalgae® 20%, respectively, compared to coal (161.3 kJ/mol) was achieved. The lowering of activation energy could be attributed to the relative fixed carbon content. SEM morphology images of ash obtained from the combustion of coal and Coalgae® 5% - 20% confirmed changes in devolatilization and combustion behaviour of solid raw fuel. The ash of Coalgae® blends had higher fluxing elements (Fe, Ca, K and Mg) than coal and this shows possibility of slagging and fouling in combustion systems. The Coalgae® blends showed a synergistic effect due to different combustion characteristics of coal and Scenedesmus microalgae. The combustion results obtained from the fixed-bed reactor showed significant reductions in concentrations of CO2, SO2 and NOx emissions for Coalgae® blends compared to baseline coal. Microalgae reduced CO2 emissions from baseline coal by 14.9%, 19.5%, 23.5% and 31.4% for Coalgae® 5%, 10%, 15% and 20%, respectively. SO2 reductions of 1.9%, 10.6%, 15.8% and 18.2%, and NOx reductions of 22.4%, 26.1%, 24.4% and 16.9% were achieved with Coalgae® 5%, 10%, 15% and 20%, respectively. Moreover, the combustion efficiency of Coalgae® blends increased significantly by up to 14.5% from baseline coal (86.4%) to Coalgae® 20% (98.9%). Based on the above findings, the co-firing of coal and Scenedesmus microalgae biomass was necessary for the reduction of CO2, SO2, and NOx emissions. As such, Coalgae® blends can be considered as alternative fuels in any coal driven process for energy generation. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Magida, Nokuthula Ethel
- 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/10948/53817 , vital:45984
- Description: There is increasingly stringent legislation on the environmental impact of energy production from coal combustion, and this has led to growing pressure to reduce the emission of greenhouse gases (GHGs). Thus, there is a significant need to develop and implement clean coal combustion technologies that would reduce the environmental gas pollutants. For power generation, the co-firing of biomass fuels at conventional coal-fired power stations is recognised as one of the low-cost, low-risk options to achieve significant reductions in GHG emissions. When coal is co-utilized with biomass there is added attractiveness because the biomass is CO2 neutral, and there is interest in using waste biomass and microalgae. Thus, the co-combustion of coal and biomass for energy production results in pollutant reduction, especially in the emissions of NOx, SOx, volatile organic compounds and polyaromatic hydrocarbons. The synergistic activity observed for toxic organic emissions is not well understood and is thought to involve chemical interaction between the volatiles from each fuel coupled with possible catalytic activity from the inorganic constituents of the fuels. The characterization of co-firing products and gases emitted from coal and microalgae (particularly the Scenedesmus strain) co-combustion has received limited attention. Therefore, this study seeks to understand possible interactions occurring during co-combustion of coal and Scenedesmus microalgae (Coalgae®). Additionally, the study aims to determine the effect of co-firing coal and Scenedesmus microalgae on CO2, SO2 and NOx emissions. The term “Coalgae®” refers to the mixture of coal and microalgae biomass. The study looks at physico-thermal characteristics as well as CO2, SO2 and NOx emissions of various coal-microalgae blending ratios by mass; 100:0 (coal), 95:5 (Coalgae® 5%), 90:10 (Coalgae® 10%), 85:15 (Coalgae® 15%) and 80:20 (Coalgae® 20%). Characterization techniques carried out included proximate and ultimate analyses, Fourier-transform infrared (FT-IR) and Scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDS). For combustion studies two techniques were applied. Low heating rate was obtained through a Thermogravimetric-Mass spectrometer analysis (TG-MS). Other combustion experiments were performed on the five lumpy fuels (coal and Coalgae® 5% - 20%) exposed to the flame in a fixed-bed combustion reactor. The emission concentrations of CO2 (%), NOx (ppm) and SO2 (ppm) of coal and Coalgae® blends were measured during the combustion of the five materials using a Lancom 4 portable flue gas analyser. The mass reduction (g) and temperature (°C) at the reactor exit were recorded during the combustion tests to compare the combustion behaviour of the four mixtures to that of raw coal. TG-DTG curves of coal and microalgae confirmed that the combustion behaviour of these materials was different. Coal showed one reaction during the combustion process, while microalgae and the Coalgae® blends showed three reactions. A significant reduction in activation energies of 160.4 kJ/mol, 159.6 kJ/mol, 151.3 kJ/mol, and 134.2 kJ/mol for Coalgae® 5% - Coalgae® 20%, respectively, compared to coal (161.3 kJ/mol) was achieved. The lowering of activation energy could be attributed to the relative fixed carbon content. SEM morphology images of ash obtained from the combustion of coal and Coalgae® 5% - 20% confirmed changes in devolatilization and combustion behaviour of solid raw fuel. The ash of Coalgae® blends had higher fluxing elements (Fe, Ca, K and Mg) than coal and this shows possibility of slagging and fouling in combustion systems. The Coalgae® blends showed a synergistic effect due to different combustion characteristics of coal and Scenedesmus microalgae. The combustion results obtained from the fixed-bed reactor showed significant reductions in concentrations of CO2, SO2 and NOx emissions for Coalgae® blends compared to baseline coal. Microalgae reduced CO2 emissions from baseline coal by 14.9%, 19.5%, 23.5% and 31.4% for Coalgae® 5%, 10%, 15% and 20%, respectively. SO2 reductions of 1.9%, 10.6%, 15.8% and 18.2%, and NOx reductions of 22.4%, 26.1%, 24.4% and 16.9% were achieved with Coalgae® 5%, 10%, 15% and 20%, respectively. Moreover, the combustion efficiency of Coalgae® blends increased significantly by up to 14.5% from baseline coal (86.4%) to Coalgae® 20% (98.9%). Based on the above findings, the co-firing of coal and Scenedesmus microalgae biomass was necessary for the reduction of CO2, SO2, and NOx emissions. As such, Coalgae® blends can be considered as alternative fuels in any coal driven process for energy generation. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
Engineering nanocatalysts using mixed metals for hydrodesulfurization of fuel oil
- Authors: Majodina, Siphumelele
- 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/10948/53861 , vital:46021
- Description: Crude oil is a complex blend containing thousands of hydrocarbons, non-hydrocarbon compounds and heavy metals. These hydrocarbons are mixed with variable quantities of sulfur-, nitrogen-, and oxygen-containing compounds. The combustion of fuel containing organosulfur compounds results in the emission of sulfur oxides (SOx) into the atmosphere. These toxic gases escape into the atmosphere resulting in air pollution, which is a large contributor to global warming. Air pollution also causes pulmonary diseases, allergies and may even lead to human death. It can also cause harm to other living organisms such as animals and food crops. Thus, mandating the reduction of sulfur in organosulfur compounds in fuel to <10 ppmS by the environmental protection agency. Several studies have been conducted to remove sulfur from fuels, most of which have focused on removing refractory sulfur compounds due to the difficulty in removing sulfur in these compounds. However, the currently employed hydrodesulfurization (HDS) catalysts suffer in producing fuels complying with the future standards of fuels quality. Generally, HDS catalysts are made up of metallic components, Co (Ni) and Mo (W), on porous supports, the catalytic activity of these catalysts strongly depends on the amount of NiWS (CoMoS) phases in it and to the extent in which these phases are exposed on the catalyst support surfaces and this is engineered using chelating agents and size of catalysts. To this end, nanosized materials (nanocatalysts) are considered most suitable, as reported active phases of HDS catalysts are exposed, hence improving the hydrodesulfurization of sulfur-containing compounds in fuels. Nanocatalysts results in nanoparticles and when impregnated on a support will results in high surface area, and enhances electronic property, which increases the activity of the catalyst allowing the most refractory sulfur to be removed. The addition of chelating agents such as EDTA, acetic acid, and citric acid further improves the activity of the catalysts by producing more active phases on the catalyst. In this research project, nanocatalysts will be synthesised using mixed metals with and without chelating agents and tested for HDS activity and selectivity towards sulfur using refractory organosulfur compounds in fuels under industrial HDS conditions. This work was divided into two sections, and this dissertation summarizes the research outcomes of each phase. The first section examines the effect of chelating ligands, namely, ethylenediaminetetraacetic acid (EDTA), citric acid (CA), and acetic acid (AA), on CoMo HDS activity and the sulfidation mechanism. In this study, chelating ligands seem to have a beneficial effect on HDS activity. Detailed mechanistic aspects of interactions between chelating ligands and metallic species (Co-chelating ligands) were also studied. Characterization by SC-XRD revealed that the presence of the chelating ligand result in the formation of complex with cobalt, and the effect of this complex was shown by TG-DSC analysis. This showed that the presence of chelating ligand leads a to delay of cobalt sulfidation as the complex decomposes at higher temperatures, which was the main cause of improving HDS activity. It was also shown that chelating ligands play a role in dispersion of metal oxides and sulfided metal oxides (TEM and XPS). XPS results showed low MoS2 phase for CoMo/Al2O3 (45%), while CoMo-EDTA/Al2O3 (63%) catalyst resulted in high MoS2 phases. From all the catalysts, CoMo-CA/Al2O3 (98%) gave the highest catalytic activity, and the increase in activity could be attributed to the formation of octahedral molybdenum oxides as they are easily reducible during sulfidation and result in more dispersed active phases and weak metal-support interaction. The second section examines the effect of a promoter (Rh) and different chelating ligands (EDTA, AA, and CA) on the catalyst RhMo supported with alumina. In this phase, rhodium was used as promoter, the following trend for catalytic activity was observed: RhMo/Al2O3 (88%) > RhMo-AA/Al2O3 (73%) > RhMo-CA/Al2O3 (72%) > RhMo-EDTA/Al2O3 (68%). This could be that the addition of chelating ligand complexed both metallic species retarding sulfidation of both metals, hence lowering the HDS activity. Studies show that it is possible for the citric acid to complex with both promoter and an active metal (Mo), and this might result in the formation of molybdenum dimers, trimers and tetramers which are difficult to sulfide. XPS analysis showed that unchelated catalyst have more MoS2 phases of 63%, hence higher dispersion than the chelated catalyst, this could be the reason for high activity in RhMo/Al2O3 (88%) catalyst. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Majodina, Siphumelele
- 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/10948/53861 , vital:46021
- Description: Crude oil is a complex blend containing thousands of hydrocarbons, non-hydrocarbon compounds and heavy metals. These hydrocarbons are mixed with variable quantities of sulfur-, nitrogen-, and oxygen-containing compounds. The combustion of fuel containing organosulfur compounds results in the emission of sulfur oxides (SOx) into the atmosphere. These toxic gases escape into the atmosphere resulting in air pollution, which is a large contributor to global warming. Air pollution also causes pulmonary diseases, allergies and may even lead to human death. It can also cause harm to other living organisms such as animals and food crops. Thus, mandating the reduction of sulfur in organosulfur compounds in fuel to <10 ppmS by the environmental protection agency. Several studies have been conducted to remove sulfur from fuels, most of which have focused on removing refractory sulfur compounds due to the difficulty in removing sulfur in these compounds. However, the currently employed hydrodesulfurization (HDS) catalysts suffer in producing fuels complying with the future standards of fuels quality. Generally, HDS catalysts are made up of metallic components, Co (Ni) and Mo (W), on porous supports, the catalytic activity of these catalysts strongly depends on the amount of NiWS (CoMoS) phases in it and to the extent in which these phases are exposed on the catalyst support surfaces and this is engineered using chelating agents and size of catalysts. To this end, nanosized materials (nanocatalysts) are considered most suitable, as reported active phases of HDS catalysts are exposed, hence improving the hydrodesulfurization of sulfur-containing compounds in fuels. Nanocatalysts results in nanoparticles and when impregnated on a support will results in high surface area, and enhances electronic property, which increases the activity of the catalyst allowing the most refractory sulfur to be removed. The addition of chelating agents such as EDTA, acetic acid, and citric acid further improves the activity of the catalysts by producing more active phases on the catalyst. In this research project, nanocatalysts will be synthesised using mixed metals with and without chelating agents and tested for HDS activity and selectivity towards sulfur using refractory organosulfur compounds in fuels under industrial HDS conditions. This work was divided into two sections, and this dissertation summarizes the research outcomes of each phase. The first section examines the effect of chelating ligands, namely, ethylenediaminetetraacetic acid (EDTA), citric acid (CA), and acetic acid (AA), on CoMo HDS activity and the sulfidation mechanism. In this study, chelating ligands seem to have a beneficial effect on HDS activity. Detailed mechanistic aspects of interactions between chelating ligands and metallic species (Co-chelating ligands) were also studied. Characterization by SC-XRD revealed that the presence of the chelating ligand result in the formation of complex with cobalt, and the effect of this complex was shown by TG-DSC analysis. This showed that the presence of chelating ligand leads a to delay of cobalt sulfidation as the complex decomposes at higher temperatures, which was the main cause of improving HDS activity. It was also shown that chelating ligands play a role in dispersion of metal oxides and sulfided metal oxides (TEM and XPS). XPS results showed low MoS2 phase for CoMo/Al2O3 (45%), while CoMo-EDTA/Al2O3 (63%) catalyst resulted in high MoS2 phases. From all the catalysts, CoMo-CA/Al2O3 (98%) gave the highest catalytic activity, and the increase in activity could be attributed to the formation of octahedral molybdenum oxides as they are easily reducible during sulfidation and result in more dispersed active phases and weak metal-support interaction. The second section examines the effect of a promoter (Rh) and different chelating ligands (EDTA, AA, and CA) on the catalyst RhMo supported with alumina. In this phase, rhodium was used as promoter, the following trend for catalytic activity was observed: RhMo/Al2O3 (88%) > RhMo-AA/Al2O3 (73%) > RhMo-CA/Al2O3 (72%) > RhMo-EDTA/Al2O3 (68%). This could be that the addition of chelating ligand complexed both metallic species retarding sulfidation of both metals, hence lowering the HDS activity. Studies show that it is possible for the citric acid to complex with both promoter and an active metal (Mo), and this might result in the formation of molybdenum dimers, trimers and tetramers which are difficult to sulfide. XPS analysis showed that unchelated catalyst have more MoS2 phases of 63%, hence higher dispersion than the chelated catalyst, this could be the reason for high activity in RhMo/Al2O3 (88%) catalyst. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
Factors influencing first-year students’ career decisions to pursue an IT career
- Authors: Twani, Malibongwe
- 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/10948/54135 , vital:46306
- Description: The process of deciding on a career is a dauntingand life-changing decision,which all scholarshave had to make. Various factors influence a first-year student’s career choice decision and selected field of study. Career decision-making,as a field of study, has been extensivelyresearched,globally. The research studies focusingon IT career choicesof studentshave indicated that scholars choosing careers in Information Technology (IT) are influenced by factors such as salaries, knowledge of career opportunities, the reputation of IT-related fields in society and by parents, teachers and role models. Recent research indicates that exposure to new technologies and programming concepts at the school level can influence a scholar’s IT career choice. Theories relating to career choice have focused on the characteristics of individuals and their environment. Career choice models have identified factors that influenced a student’s career choice.In South Africahowever,there have been limited studies investigating the factors influencing students’ career decisions in choosing careers in Computer Science (CS), Information Systems (IS) and Information Technology (IT)using mixed-methods.This study aims to investigate the factors that influence first-year students’ decisionsin choosing an IT career at the Nelson Mandela University.The research study pursueda pragmatisticapproach,using a mixed-methods approach. In investigating theories andfactors that influence students’ decisionsin choosing IT careers,the study used systematic literature reviews. The decision-making theories and factorsin theliterature review facilitated the creation of the conceptual framework for IT career decision making. A questionnaire was developed and distributed amongst ITand Non-ITfirst-year studentsin 2021. Fourhundredand eightparticipants completed the survey. The data obtained from the survey were statistically analysed, includingdescriptive analysis andExploratory Factor Analysis(EFA). Additionally, inferential statistics were used namely; Correlations, t-test, Confirmatory Factor Analysis(CFA)and Structural Equation Modelling(SEM). The study results wereinterpreted andcompared with iiiotherrelevantstudies. Recommendations were madeto address the factorsthat influencefirst-year students’ IT career decisions.The study highlighted that high academic confidence and personal attributes amongststudents,whowereinvolved at an early age in programming and using computers,chose IT as a career. The study showed significant statistical differences betweenIT and Non-IT groups in perceptions about the IT industry and identifying job title descriptions.Additionally, a significant statistical difference between languages and genders was identified in understanding careers. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Twani, Malibongwe
- 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/10948/54135 , vital:46306
- Description: The process of deciding on a career is a dauntingand life-changing decision,which all scholarshave had to make. Various factors influence a first-year student’s career choice decision and selected field of study. Career decision-making,as a field of study, has been extensivelyresearched,globally. The research studies focusingon IT career choicesof studentshave indicated that scholars choosing careers in Information Technology (IT) are influenced by factors such as salaries, knowledge of career opportunities, the reputation of IT-related fields in society and by parents, teachers and role models. Recent research indicates that exposure to new technologies and programming concepts at the school level can influence a scholar’s IT career choice. Theories relating to career choice have focused on the characteristics of individuals and their environment. Career choice models have identified factors that influenced a student’s career choice.In South Africahowever,there have been limited studies investigating the factors influencing students’ career decisions in choosing careers in Computer Science (CS), Information Systems (IS) and Information Technology (IT)using mixed-methods.This study aims to investigate the factors that influence first-year students’ decisionsin choosing an IT career at the Nelson Mandela University.The research study pursueda pragmatisticapproach,using a mixed-methods approach. In investigating theories andfactors that influence students’ decisionsin choosing IT careers,the study used systematic literature reviews. The decision-making theories and factorsin theliterature review facilitated the creation of the conceptual framework for IT career decision making. A questionnaire was developed and distributed amongst ITand Non-ITfirst-year studentsin 2021. Fourhundredand eightparticipants completed the survey. The data obtained from the survey were statistically analysed, includingdescriptive analysis andExploratory Factor Analysis(EFA). Additionally, inferential statistics were used namely; Correlations, t-test, Confirmatory Factor Analysis(CFA)and Structural Equation Modelling(SEM). The study results wereinterpreted andcompared with iiiotherrelevantstudies. Recommendations were madeto address the factorsthat influencefirst-year students’ IT career decisions.The study highlighted that high academic confidence and personal attributes amongststudents,whowereinvolved at an early age in programming and using computers,chose IT as a career. The study showed significant statistical differences betweenIT and Non-IT groups in perceptions about the IT industry and identifying job title descriptions.Additionally, a significant statistical difference between languages and genders was identified in understanding careers. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
Ifuthe lenkolo yobuKristu kulwimi lwesiXhosa
- Authors: Mwanda, Siyasanga Pulani
- 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/10948/54511 , vital:46617
- Description: Le ngxongxo iza kuthi ithethe ngefuthe lenkolo yobuKristu kulwimi lwesiXhosa. Akuyomfihlo ukuba ulwimi luthi lukhule okanye ludodobale ngenxa yendlela abantu bolwimi abaphila ngayo notshintsho oluthi lubekho kwindlela abaphila ngayo. AmaXhosa ke athi nawo aziswa kwinkolo yobuKristu. Le ngxoxo iza kuthi icacise ngokuthe gca ithiyori yeSimiyotiki esisiseko sesi sifundo, idakance iizimvo zeengcali zeSimiyotiki, ize ke iveze amagama amatsha ayengekho esiXhoseni mhla mnene, intsusa yalamagama nentsingiselo yawo. Okwesibini izakuthi ivelele intsingiselo yemiqondiso neempawu zobuKristu negalelo lazo kulwimi lwesiXhosa. Okokugqibela iza kuthi iveze izaci namaqhalo esiXhosa angobuKristu. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Mwanda, Siyasanga Pulani
- 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/10948/54511 , vital:46617
- Description: Le ngxongxo iza kuthi ithethe ngefuthe lenkolo yobuKristu kulwimi lwesiXhosa. Akuyomfihlo ukuba ulwimi luthi lukhule okanye ludodobale ngenxa yendlela abantu bolwimi abaphila ngayo notshintsho oluthi lubekho kwindlela abaphila ngayo. AmaXhosa ke athi nawo aziswa kwinkolo yobuKristu. Le ngxoxo iza kuthi icacise ngokuthe gca ithiyori yeSimiyotiki esisiseko sesi sifundo, idakance iizimvo zeengcali zeSimiyotiki, ize ke iveze amagama amatsha ayengekho esiXhoseni mhla mnene, intsusa yalamagama nentsingiselo yawo. Okwesibini izakuthi ivelele intsingiselo yemiqondiso neempawu zobuKristu negalelo lazo kulwimi lwesiXhosa. Okokugqibela iza kuthi iveze izaci namaqhalo esiXhosa angobuKristu. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text:
- Date Issued: 2021-12
Igalelo lokutshintsha-tshintsha ulwimi xa kufundiswa isiXhosa kwigumbi lokufundela kwibanga le-12
- Authors: Mini, Nolwandle
- 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/10948/54506 , vital:46619
- Description: Olu phando luza kugxila kwigalelo lokutshintsha kolwimi xa kufundiswa isiXhosa kwizikolo ezifundisa isiXhosa kulwimi olongezelweyo. Lo msebenzi wolu phando usekeleze kwigalelo lokutshintshwa tshintshwa kolwimi xa kufundiswa isiXhosa kwigumbi lokufundela. Olu phando luza Kubeka iliso elibanzi kwindlela ekuhlolwa ngalo ulwimi olongezelweleyo kunye nengxelo yeziphumo zokuphela konyaka wama – 2016 nowama- 2017. Abavavanyi kwingxelo zovavanya zovavanyo bayibeke elubala into yokungaphumeleli kwabafundi ngenxa yefuthe lokungawuvi umbuzo. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Mini, Nolwandle
- 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/10948/54506 , vital:46619
- Description: Olu phando luza kugxila kwigalelo lokutshintsha kolwimi xa kufundiswa isiXhosa kwizikolo ezifundisa isiXhosa kulwimi olongezelweyo. Lo msebenzi wolu phando usekeleze kwigalelo lokutshintshwa tshintshwa kolwimi xa kufundiswa isiXhosa kwigumbi lokufundela. Olu phando luza Kubeka iliso elibanzi kwindlela ekuhlolwa ngalo ulwimi olongezelweleyo kunye nengxelo yeziphumo zokuphela konyaka wama – 2016 nowama- 2017. Abavavanyi kwingxelo zovavanya zovavanyo bayibeke elubala into yokungaphumeleli kwabafundi ngenxa yefuthe lokungawuvi umbuzo. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2021
- Full Text: false
- Date Issued: 2021-12
In-vitroevaluation of bridelia ferruginea extract gold nanoparticles for the treatment of colon cancer
- Zosela, Itumeleng, Davids, Hajierah
- Authors: Zosela, Itumeleng , Davids, Hajierah
- 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/10948/54124 , vital:46311
- Description: Colorectal cancer (CRC) has become a health burden, being the third common cancer worldwide. Treatment of colorectal cancer is very important to manage the high prevalence rate of this disease. The available treatments for CRC have their drawbacks and side effects. Available treatments of colon cancer include surgery, chemotherapy, and radiation. Due to the side effects associated with these treatments, alternative treatments that pose less side effects are being developed worldwide. Nanotechnologies have gained global consideration due to their potential to improve the current standards and techniques for the diagnosis and treatment. The use of plants for synthesis of gold nanoparticles has opened a new venture of synthesizing environmentally friendly and cost-effective nanoparticles which possess great properties for CRC treatment. The aim of this study was to investigate the use of green synthesized AuNPs from Bridelia ferruginea for potential cancer treatment. In this work study gold nanoparticles were synthesized utilizing Bridelia ferruginea stem bark extract. The nanoparticles were characterized using UV–Vis spectroscopy, Dynamic Light Scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and High-Resolution Transmission Electron Microscopy (HRTEM). The in vitroanti cancer activity of the AuNPs was investigated using Presto Blue assay, cellular morphology, caspase 3/7 assay on the human colon cancer cell line at different times to assess the optimum time for cell death. The cellular uptake and localization of AuNPs was investigated using HRTEM to assess uptake and location of the AuNPs within the cell. Results obtained from this study showed that the AuNP synthesis from Bridellia ferrugenia was successful. The Presto Blue cell viability results showed that the AuNPs reduced cell viability (%) significantly (p<0.05) after 24 h. The optimum treatment time of HT-29 cells with AuNPs was determined to be 24 h. The apoptotic effects of the AuNPs were assessed using Cell Event reagent, and the results from this assay indicated that caspase 3/7 was activated with treatment with AuNPs which induced cell death via apoptosis. The HRTEM results indicated that there was no uptake of AuNP targeting in HT-29 therefore localization could not be determined. It can be concluded that the AuNPs synthesized from Bridellia ferrugenia have anti-cancer properties and are able to induce cell death through apoptosis. Furthermore, this study revealed that optimization of the AuNPs for cellular uptake is needed to further understand the interaction between the nanoparticles and the cells. This will provide more insight on how cellular death is induced by the nanoparticles. , Thesis (MSc) -- Faculty of Science, Department of Biochemistry and Microbiology (including Physiology), 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Zosela, Itumeleng , Davids, Hajierah
- 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/10948/54124 , vital:46311
- Description: Colorectal cancer (CRC) has become a health burden, being the third common cancer worldwide. Treatment of colorectal cancer is very important to manage the high prevalence rate of this disease. The available treatments for CRC have their drawbacks and side effects. Available treatments of colon cancer include surgery, chemotherapy, and radiation. Due to the side effects associated with these treatments, alternative treatments that pose less side effects are being developed worldwide. Nanotechnologies have gained global consideration due to their potential to improve the current standards and techniques for the diagnosis and treatment. The use of plants for synthesis of gold nanoparticles has opened a new venture of synthesizing environmentally friendly and cost-effective nanoparticles which possess great properties for CRC treatment. The aim of this study was to investigate the use of green synthesized AuNPs from Bridelia ferruginea for potential cancer treatment. In this work study gold nanoparticles were synthesized utilizing Bridelia ferruginea stem bark extract. The nanoparticles were characterized using UV–Vis spectroscopy, Dynamic Light Scattering (DLS), Fourier Transform Infrared Spectroscopy (FTIR) and High-Resolution Transmission Electron Microscopy (HRTEM). The in vitroanti cancer activity of the AuNPs was investigated using Presto Blue assay, cellular morphology, caspase 3/7 assay on the human colon cancer cell line at different times to assess the optimum time for cell death. The cellular uptake and localization of AuNPs was investigated using HRTEM to assess uptake and location of the AuNPs within the cell. Results obtained from this study showed that the AuNP synthesis from Bridellia ferrugenia was successful. The Presto Blue cell viability results showed that the AuNPs reduced cell viability (%) significantly (p<0.05) after 24 h. The optimum treatment time of HT-29 cells with AuNPs was determined to be 24 h. The apoptotic effects of the AuNPs were assessed using Cell Event reagent, and the results from this assay indicated that caspase 3/7 was activated with treatment with AuNPs which induced cell death via apoptosis. The HRTEM results indicated that there was no uptake of AuNP targeting in HT-29 therefore localization could not be determined. It can be concluded that the AuNPs synthesized from Bridellia ferrugenia have anti-cancer properties and are able to induce cell death through apoptosis. Furthermore, this study revealed that optimization of the AuNPs for cellular uptake is needed to further understand the interaction between the nanoparticles and the cells. This will provide more insight on how cellular death is induced by the nanoparticles. , Thesis (MSc) -- Faculty of Science, Department of Biochemistry and Microbiology (including Physiology), 2021
- Full Text:
- Date Issued: 2021-12
Investigating customary marriage conflict among the Ndebele speaking people in Mathula Village in Limpopo Province
- Authors: Msiza, Dina
- 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/10948/54504 , vital:46618
- Description: Recognition of Customary Marriages Act of 1998 in South Africa remains one of the greatest initiatives towards equality amongst spouses. However, even with the RCMA of 1998 that is set to regulate customary marriages, customary marriage conflict remains rife across various ethnic groups in South Africa. The RCMA of 1998 leaves a lot of room for interpretation by different cultures and some elements that certain ethnic groups consider as crucial in fulfilling customary marriages are excluded. So, to contribute to Conflict Studies with reference to customary marriage conflict, this study investigated customary marriage conflict among Ndebele speaking people in Mathula Village in Limpopo. The purpose of this study was to investigate the causes of customary marriage among Ndebele speaking people in Mathula Village in Limpopo. Data was collected through semi-structured interviews and analysed through content analysis, coding, and thematic analysis. During the interviews, non-participant observation was used. Purposeful sampling was used to select participants. In the final analysis, this study provides some recommendations with the view of addressing some of the challenges that were identified. Some of the recommendations include that there is a need to rethink the process of customary marriage in relation to the payment of lobola. Further, there is a need for an in-depth research going forward. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Msiza, Dina
- 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/10948/54504 , vital:46618
- Description: Recognition of Customary Marriages Act of 1998 in South Africa remains one of the greatest initiatives towards equality amongst spouses. However, even with the RCMA of 1998 that is set to regulate customary marriages, customary marriage conflict remains rife across various ethnic groups in South Africa. The RCMA of 1998 leaves a lot of room for interpretation by different cultures and some elements that certain ethnic groups consider as crucial in fulfilling customary marriages are excluded. So, to contribute to Conflict Studies with reference to customary marriage conflict, this study investigated customary marriage conflict among Ndebele speaking people in Mathula Village in Limpopo. The purpose of this study was to investigate the causes of customary marriage among Ndebele speaking people in Mathula Village in Limpopo. Data was collected through semi-structured interviews and analysed through content analysis, coding, and thematic analysis. During the interviews, non-participant observation was used. Purposeful sampling was used to select participants. In the final analysis, this study provides some recommendations with the view of addressing some of the challenges that were identified. Some of the recommendations include that there is a need to rethink the process of customary marriage in relation to the payment of lobola. Further, there is a need for an in-depth research going forward. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2021
- Full Text:
- Date Issued: 2021-12
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
- Full Text: false
- Date Issued: 2021-12
- 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
- Full Text: false
- 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
- Full Text:
- Date Issued: 2021-12
- 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
- Full Text:
- Date Issued: 2021-12
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
- Full Text:
- Date Issued: 2021-12
- 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
- Full Text:
- 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
- Full Text:
- Date Issued: 2021-12
- 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
- Full Text:
- Date Issued: 2021-12