Early stage ichthyofauna from shallow water habitats of the Angola-Benguela frontal zone
- Authors: Farthing, Matthew William
- Date: 2017
- Subjects: Fishes -- Larvae -- South Africa -- Atlantic coast , Fishes -- Larvae -- Angola -- Atlantic coast , Striped mullet -- Angola -- Atlantic coast
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/50442 , vital:25988
- Description: Early stage fishes (larvae and early juveniles) were collected from an array of shallow water (±1.5m) habitats on the warm-temperate southern Angolan coastline between June 2014 and June 2015. This study, the first assessment of the early stages of coastal fishes in Angola, provides important new understanding of non-estuarine shallow water nursery habitat use by coastal fishes from the region. In total, 51 species from 18 teleost families were observed. The exposed surf zone was dominated by postflexion larvae, while the moderately exposed beach and sheltered bay were dominated by early juveniles. Both fish density and diversity peaked in the wet season (Feb – Apr 2015) for all habitats, attributed to the influx of summer spawning species. Diplodus sargus dominated catches from the exposed surf zone, and the timing of observations supports the growing consensus that sparid spawning is dictated by temperature, not season. The similitude of the observed species to those observed in warm temperate South Africa highlights the historical connection of the warm-temperate study area with warm-temperate South Africa, prior to the formation of the Benguela Current as a vicariant barrier. The classification of the study assemblage into established estuarine utilization categories showed that the surf zone hosted more exclusively marine species than comparable surf zones in South Africa, attributed to the absence of estuaries in southern Angola. However, the observation of the marine estuarine dependent Mugil cephalus in this study area devoid of estuaries suggests that estuarine dependency may be regionally specific for some taxa. It appears that the warm, sheltered, nutrient rich waters of Tombua Bay provide typically estuarine associated taxa with a suitable alternative, non-estuarine nursery habitat. This study provides evidence that the importance of estuaries as critical nursery habitats has been overemphasized for some warm-temperate coastal fishes. However, the absence of other marine estuarine dependent species from the study area suggests that some warm-temperate taxa do intrinsically rely on estuarine function for survival.
- Full Text:
- Date Issued: 2017
- Authors: Farthing, Matthew William
- Date: 2017
- Subjects: Fishes -- Larvae -- South Africa -- Atlantic coast , Fishes -- Larvae -- Angola -- Atlantic coast , Striped mullet -- Angola -- Atlantic coast
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/50442 , vital:25988
- Description: Early stage fishes (larvae and early juveniles) were collected from an array of shallow water (±1.5m) habitats on the warm-temperate southern Angolan coastline between June 2014 and June 2015. This study, the first assessment of the early stages of coastal fishes in Angola, provides important new understanding of non-estuarine shallow water nursery habitat use by coastal fishes from the region. In total, 51 species from 18 teleost families were observed. The exposed surf zone was dominated by postflexion larvae, while the moderately exposed beach and sheltered bay were dominated by early juveniles. Both fish density and diversity peaked in the wet season (Feb – Apr 2015) for all habitats, attributed to the influx of summer spawning species. Diplodus sargus dominated catches from the exposed surf zone, and the timing of observations supports the growing consensus that sparid spawning is dictated by temperature, not season. The similitude of the observed species to those observed in warm temperate South Africa highlights the historical connection of the warm-temperate study area with warm-temperate South Africa, prior to the formation of the Benguela Current as a vicariant barrier. The classification of the study assemblage into established estuarine utilization categories showed that the surf zone hosted more exclusively marine species than comparable surf zones in South Africa, attributed to the absence of estuaries in southern Angola. However, the observation of the marine estuarine dependent Mugil cephalus in this study area devoid of estuaries suggests that estuarine dependency may be regionally specific for some taxa. It appears that the warm, sheltered, nutrient rich waters of Tombua Bay provide typically estuarine associated taxa with a suitable alternative, non-estuarine nursery habitat. This study provides evidence that the importance of estuaries as critical nursery habitats has been overemphasized for some warm-temperate coastal fishes. However, the absence of other marine estuarine dependent species from the study area suggests that some warm-temperate taxa do intrinsically rely on estuarine function for survival.
- Full Text:
- Date Issued: 2017
Experiences of pet loss in the South African context
- Authors: Lowen, Kathleen Louise
- Date: 2017
- Subjects: Pet loss -- Psychological aspects , Pet loss -- South Africa -- Case studies , Pets -- Death , Pet ownders -- Psychology , Human-animal relationships -- Psychological aspects , Grief
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4326 , vital:20649
- Description: In this research the experience of pet loss in relation to the intensity of grief and the repression of that grief due to societal restrictions was studied in a South African sample of 12 pet owners who had experienced the loss of a pet within 24 months prior to the study. A pilot study was conducted in order to refine the semi-structured interview schedule. Participants were asked about their pets, their experience of pet loss in relation to their feelings before and after the loss and whether they felt they could openly grieve around friends and family. The findings indicated that the intensity of grief experienced by the participants was influenced both by the intensity of their Bond with the pet and the repression of their grief due to assumed social sanctions surrounding mourning the loss of a pet. The findings from the study clearly indicate the necessity for pet loss counselling, however it was clear that societal views surrounding pet loss are shifting, thus allowing pet owners to mourn their loss more openly with family and friends. This indicates a decrease in cases of disenfranchised and complicated grief. Furthermore the impact of pet loss necessitates the social legitimation and acknowledgment of the significance of pet loss in contemporary society as these relationships with pets are an increasingly prominent feature both within and as an alternative to familial systems.
- Full Text:
- Date Issued: 2017
- Authors: Lowen, Kathleen Louise
- Date: 2017
- Subjects: Pet loss -- Psychological aspects , Pet loss -- South Africa -- Case studies , Pets -- Death , Pet ownders -- Psychology , Human-animal relationships -- Psychological aspects , Grief
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4326 , vital:20649
- Description: In this research the experience of pet loss in relation to the intensity of grief and the repression of that grief due to societal restrictions was studied in a South African sample of 12 pet owners who had experienced the loss of a pet within 24 months prior to the study. A pilot study was conducted in order to refine the semi-structured interview schedule. Participants were asked about their pets, their experience of pet loss in relation to their feelings before and after the loss and whether they felt they could openly grieve around friends and family. The findings indicated that the intensity of grief experienced by the participants was influenced both by the intensity of their Bond with the pet and the repression of their grief due to assumed social sanctions surrounding mourning the loss of a pet. The findings from the study clearly indicate the necessity for pet loss counselling, however it was clear that societal views surrounding pet loss are shifting, thus allowing pet owners to mourn their loss more openly with family and friends. This indicates a decrease in cases of disenfranchised and complicated grief. Furthermore the impact of pet loss necessitates the social legitimation and acknowledgment of the significance of pet loss in contemporary society as these relationships with pets are an increasingly prominent feature both within and as an alternative to familial systems.
- Full Text:
- Date Issued: 2017
The impact of good news and bad news on South Africa’s sectoral stock return volatility: an asymmetric GARCH analysis
- Authors: Muzinda, Edmond Toreva
- Date: 2017
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/6425 , vital:21108
- Description: This study explores the impact of good news and bad news on South Africa’s sectoral stock return volatility using an asymmetric GARCH analysis. Understanding the different impact of news on stock return volatility in different economic sectors has important implications for investors’ risk management practices, portfolio allocation strategies and asset pricing. The study employs data of daily closing prices for nine sectors and three benchmark indices for the period 2nd January 1997 - 17th August 2016. The data was split into sub-samples of pre-, during and post-global financial crisis, as well as the overall sample period. The incorporation of sub-samples was to help explain the outcomes of the overall sample period. To capture the different impact of good news and bad news on stock return volatility for each sector, asymmetric GARCH models namely, TGARCH and EGARCH were employed. The findings from this study revealed that volatility asymmetry was present in all sectors and benchmark indices of South African equity market. Bad news had more impact on stock return volatility for all sectors except the Oil and Gas sector, than good news of the same magnitude. In the Oil and Gas sector, good news was found to have an amplified effect on return volatility compared with bad news of the same magnitude. High volatility persistence was also found to be present in the Consumer goods, Financials, Industrials, All-share index and Mid-cap index. High differential impact of good and bad news were found in the Industrials, Financials, Basic materials, Consumer goods and the All-share index. Since the main objective of this study was to provide explanations of volatility asymmetry found in the South African sectors, the following were proposed as possible explanations of the findings. Within sectors, volatility asymmetry was explained by financial leverage, the role of the media, loss-averse investors and the behaviour of traders (overconfidence and extrapolation bias). Volatility asymmetry across sectors was explained by information flow, the uneven distribution of information by the media, investor sentiments, investor expectations and trading volumes. Overall, the results indicate that the stock return volatility of individual sectors of the South African equity market is driven mainly by bad news (except for Oil and Gas) and that leverage effects exist in all the sectors and in the benchmark indices.
- Full Text:
- Date Issued: 2017
- Authors: Muzinda, Edmond Toreva
- Date: 2017
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/6425 , vital:21108
- Description: This study explores the impact of good news and bad news on South Africa’s sectoral stock return volatility using an asymmetric GARCH analysis. Understanding the different impact of news on stock return volatility in different economic sectors has important implications for investors’ risk management practices, portfolio allocation strategies and asset pricing. The study employs data of daily closing prices for nine sectors and three benchmark indices for the period 2nd January 1997 - 17th August 2016. The data was split into sub-samples of pre-, during and post-global financial crisis, as well as the overall sample period. The incorporation of sub-samples was to help explain the outcomes of the overall sample period. To capture the different impact of good news and bad news on stock return volatility for each sector, asymmetric GARCH models namely, TGARCH and EGARCH were employed. The findings from this study revealed that volatility asymmetry was present in all sectors and benchmark indices of South African equity market. Bad news had more impact on stock return volatility for all sectors except the Oil and Gas sector, than good news of the same magnitude. In the Oil and Gas sector, good news was found to have an amplified effect on return volatility compared with bad news of the same magnitude. High volatility persistence was also found to be present in the Consumer goods, Financials, Industrials, All-share index and Mid-cap index. High differential impact of good and bad news were found in the Industrials, Financials, Basic materials, Consumer goods and the All-share index. Since the main objective of this study was to provide explanations of volatility asymmetry found in the South African sectors, the following were proposed as possible explanations of the findings. Within sectors, volatility asymmetry was explained by financial leverage, the role of the media, loss-averse investors and the behaviour of traders (overconfidence and extrapolation bias). Volatility asymmetry across sectors was explained by information flow, the uneven distribution of information by the media, investor sentiments, investor expectations and trading volumes. Overall, the results indicate that the stock return volatility of individual sectors of the South African equity market is driven mainly by bad news (except for Oil and Gas) and that leverage effects exist in all the sectors and in the benchmark indices.
- Full Text:
- Date Issued: 2017
“The Hellenistic ruler cult and Ptolemy I’s quest for legitimacy”
- Authors: Ntuli, Sihle
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6097 , vital:21031
- Description: Alexander III died suddenly in Babylon in 323 BC. With Philip III Arrhidaeus in a mentally deficient state and Alexander IV not being of age, Alexander died without a suitable heir. The task of succeeding one of the most storied legacies in the ancient world was left to the generals of Alexander III. On his deathbed, Alexander was asked who should lead the Macedonians, of which he allegedly replied “the strongest”. Thus began the process of selecting the individual who would succeed Alexander the Great, which ended up becoming a contentious task due to Macedonian succession customs. Subsequently the ‘Successors’ quarrelled over who should succeed Alexander as the true successor. The wars of the Successors are founded on an issue of legitimacy that qualifies the notion of the strongest. Being deemed the true successor of Alexander the Great meant the opportunity to continue a period of Macedonian dominance following the reigns of Philip II and Alexander III. Alexander III is hailed as one of the most extraordinary individuals of the ancient world with his imperial campaigns being widely documented, political stability being pinpointed as one of the Macedonian strong points during the period of their dominance. The ruler cult is a point of reference for the explaining the relative political stability throughout the reign of Alexander the Great. The ruler cult can be understood as a sociopolitical construct that hybridized the notion of the ruler with that of a religious leader. The oriental influence of Alexander’s campaigns in Asia would inform the customs and practices of the divine ruler. The Macedonians’ ability to establish a presence in foreign territories made such a social construct a necessity in the task of centralizing of minds for political stability. Alexander’s rendition of the cult informed the formalized Ptolemaic ruler cult. The similarities and differences of the renditions help us to understand this political tool that Ptolemy I required in order to be deemed the true successor of Alexander the Great. The following will be an investigation into whether Ptolemy I is able to attain legitimacy, firstly as a successor to Alexander the Great, secondly as Pharaoh of Egypt.
- Full Text:
- Date Issued: 2017
- Authors: Ntuli, Sihle
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6097 , vital:21031
- Description: Alexander III died suddenly in Babylon in 323 BC. With Philip III Arrhidaeus in a mentally deficient state and Alexander IV not being of age, Alexander died without a suitable heir. The task of succeeding one of the most storied legacies in the ancient world was left to the generals of Alexander III. On his deathbed, Alexander was asked who should lead the Macedonians, of which he allegedly replied “the strongest”. Thus began the process of selecting the individual who would succeed Alexander the Great, which ended up becoming a contentious task due to Macedonian succession customs. Subsequently the ‘Successors’ quarrelled over who should succeed Alexander as the true successor. The wars of the Successors are founded on an issue of legitimacy that qualifies the notion of the strongest. Being deemed the true successor of Alexander the Great meant the opportunity to continue a period of Macedonian dominance following the reigns of Philip II and Alexander III. Alexander III is hailed as one of the most extraordinary individuals of the ancient world with his imperial campaigns being widely documented, political stability being pinpointed as one of the Macedonian strong points during the period of their dominance. The ruler cult is a point of reference for the explaining the relative political stability throughout the reign of Alexander the Great. The ruler cult can be understood as a sociopolitical construct that hybridized the notion of the ruler with that of a religious leader. The oriental influence of Alexander’s campaigns in Asia would inform the customs and practices of the divine ruler. The Macedonians’ ability to establish a presence in foreign territories made such a social construct a necessity in the task of centralizing of minds for political stability. Alexander’s rendition of the cult informed the formalized Ptolemaic ruler cult. The similarities and differences of the renditions help us to understand this political tool that Ptolemy I required in order to be deemed the true successor of Alexander the Great. The following will be an investigation into whether Ptolemy I is able to attain legitimacy, firstly as a successor to Alexander the Great, secondly as Pharaoh of Egypt.
- Full Text:
- Date Issued: 2017
Deriving norms for learners in the disadvantaged schools of the peri-urban areas of the Eastern Cape: the case of the Vassiliou Mathematics Proficiency Test (VASSI)
- Masango, Siphesihle Polkadot
- Authors: Masango, Siphesihle Polkadot
- Date: 2017
- Subjects: VASSI Mathematics Proficiency Test , Mathematical ability -- Testing -- South Africa , Educational tests and measurements -- South Africa , Children with social disabilities -- Education -- South Africa , Children with social disabilities -- Education -- South Africa -- Makhanda -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/49929 , vital:25943
- Description: This study builds on South African cross-cultural research which highlights the need for careful stratification of normative samples for quality of education and geographical location. The aim of the present study was to produce an expanded set of preliminary norms for learners in the disadvantaged schools of the peri-urban areas of the Eastern Cape, Grahamstown, on the Vassiliou Mathematics Foundation Phase Test (VASSI) and Vassiliou Mathematics Proficiency Test (VASSI), respectively. The test was administered to Grade 1-6 learners in four different schools all within Joza location, Grahamstown. For the learners’ convenience the tests were translated into isiXhosa, the translations were provided together with the original English questions. Archival data collected by honours students was also incorporated in this study. The total number of participants was N=724 which was comprised of 147 grade 1s, 123 grade 2s, 117 grade 3s, 128 grade 4s, 113 grade 5s and 96 grade 6s. Norm-referenced criterion was used in analysing the data. The results of this study are in accordance with those purporting the low performance of disadvantaged learners on the school subject, mathematics. Stanines for the various grades (Grade 1 to 6) were calculated and are presented in the study. This study has demonstrated that although gender, language and other ethnic variables have an impact on mathematics performance, quality of education and socioeconomic status have a significant effect. Further research is needed on the effect of quality of education and socioeconomic status on learners in disadvantaged schools on this test in particular.
- Full Text:
- Date Issued: 2017
- Authors: Masango, Siphesihle Polkadot
- Date: 2017
- Subjects: VASSI Mathematics Proficiency Test , Mathematical ability -- Testing -- South Africa , Educational tests and measurements -- South Africa , Children with social disabilities -- Education -- South Africa , Children with social disabilities -- Education -- South Africa -- Makhanda -- Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/49929 , vital:25943
- Description: This study builds on South African cross-cultural research which highlights the need for careful stratification of normative samples for quality of education and geographical location. The aim of the present study was to produce an expanded set of preliminary norms for learners in the disadvantaged schools of the peri-urban areas of the Eastern Cape, Grahamstown, on the Vassiliou Mathematics Foundation Phase Test (VASSI) and Vassiliou Mathematics Proficiency Test (VASSI), respectively. The test was administered to Grade 1-6 learners in four different schools all within Joza location, Grahamstown. For the learners’ convenience the tests were translated into isiXhosa, the translations were provided together with the original English questions. Archival data collected by honours students was also incorporated in this study. The total number of participants was N=724 which was comprised of 147 grade 1s, 123 grade 2s, 117 grade 3s, 128 grade 4s, 113 grade 5s and 96 grade 6s. Norm-referenced criterion was used in analysing the data. The results of this study are in accordance with those purporting the low performance of disadvantaged learners on the school subject, mathematics. Stanines for the various grades (Grade 1 to 6) were calculated and are presented in the study. This study has demonstrated that although gender, language and other ethnic variables have an impact on mathematics performance, quality of education and socioeconomic status have a significant effect. Further research is needed on the effect of quality of education and socioeconomic status on learners in disadvantaged schools on this test in particular.
- Full Text:
- Date Issued: 2017
Exploring the relationship between course pedagogy and learning in workplaces: the case of the National Diploma in Environmental Education Training and Development Practice
- Authors: Misser, Shanu
- Date: 2017
- Subjects: National Diploma in Environmental Education Training and Development Practice , Environmental education -- South Africa , Occupational training -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8104 , vital:21354
- Description: This case study research provides insights on course pedagogy in the National Diploma in Environmental Education Training and Development Practice as registered with the South African Qualifications Authority. The study draws its findings from interviews, observations, and document analysis of course materials and workshop processes. The two case studies of employees working in a municipal and a provincial context in South Africa provide rich insights into workplace practices and its implications for pedagogical approaches in work-integrated courses. The role of scaffolding, reflexivity and situated learning in creating learning experiences that learners have a reason to value emerge as significant approaches to be considered in pedagogy for work-integrated courses. Critical open-ended questions supported by course material design, dialogue, participation in cooperative learning situation underpinned by reading and the use of case studies and real situated experiences emerge as important pedagogical approaches enabling scaffolding and reflexivity to support a “critical mode of being”. The significant role of pedagogical approaches in maintaining relevance to workplace practices are seen as important in developing capabilities of participants to value what they do on courses. Linked to the insights gained from this study three important recommendations are made. The first recommendation suggests that a pedagogical approach, which involves learner-practitioners and workplace representatives in the curriculum design, would help to maintain relevance of the assignments to the workplace. The second recommendation suggests creative and innovative pedagogical approaches to capture workplace practices in real authentic and meaningful situations for assessment. The third recommendation suggests that pedagogies used in workplace courses need to consider social-ecological sustainability competencies that transgress job tasks across occupations which foster appreciation and imagination of new possibilities in the work learner-practitioners engage in.
- Full Text:
- Date Issued: 2017
- Authors: Misser, Shanu
- Date: 2017
- Subjects: National Diploma in Environmental Education Training and Development Practice , Environmental education -- South Africa , Occupational training -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8104 , vital:21354
- Description: This case study research provides insights on course pedagogy in the National Diploma in Environmental Education Training and Development Practice as registered with the South African Qualifications Authority. The study draws its findings from interviews, observations, and document analysis of course materials and workshop processes. The two case studies of employees working in a municipal and a provincial context in South Africa provide rich insights into workplace practices and its implications for pedagogical approaches in work-integrated courses. The role of scaffolding, reflexivity and situated learning in creating learning experiences that learners have a reason to value emerge as significant approaches to be considered in pedagogy for work-integrated courses. Critical open-ended questions supported by course material design, dialogue, participation in cooperative learning situation underpinned by reading and the use of case studies and real situated experiences emerge as important pedagogical approaches enabling scaffolding and reflexivity to support a “critical mode of being”. The significant role of pedagogical approaches in maintaining relevance to workplace practices are seen as important in developing capabilities of participants to value what they do on courses. Linked to the insights gained from this study three important recommendations are made. The first recommendation suggests that a pedagogical approach, which involves learner-practitioners and workplace representatives in the curriculum design, would help to maintain relevance of the assignments to the workplace. The second recommendation suggests creative and innovative pedagogical approaches to capture workplace practices in real authentic and meaningful situations for assessment. The third recommendation suggests that pedagogies used in workplace courses need to consider social-ecological sustainability competencies that transgress job tasks across occupations which foster appreciation and imagination of new possibilities in the work learner-practitioners engage in.
- Full Text:
- Date Issued: 2017
Language and literacy development for a Grade 10 English first additional language classroom: a reading to learn case study
- Authors: Mataka, Tawanda Wallace
- Date: 2017
- Subjects: English language -- Study and teching (Secondary) -- South Africa Reading -- Study and teching (Secondary) -- South Africa Literacy -- Study and teching (Secondary) -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/249 , vital:19941
- Description: The problem of poor reading skills is a serious one in South Africa, with negative implications for learners’ educational achievement. The failure of learners to read at age- and grade-appropriate levels presents a major challenge to the teaching of reading in South African schools. It is against this background that this study aimed at ascertaining the positive impact of the Reading to Learn methodology in improving the literacy levels of learners in a Grade 10 English First Additional Language classroom in a township school. Reading ability levels were established via a passage extracted from a Grade Platinum English First Additional Learner’s book. Pronunciation and word recognition formed the basis of the reading assessment. Reading translates into writing, so the learners were also assessed in comprehension and creative writing. The results indicated that the learners’ reading abilities were weak, the methodology used to teach reading led to research findings that caused the study to yield findings that suggest that RtL may be the solution to reading problems in the classroom. In addition the study revealed that the ability to read corresponds with cognitive development. The study therefore calls for the adoption of RtL to assist in alleviating reading problems in the classroom.
- Full Text:
- Date Issued: 2017
- Authors: Mataka, Tawanda Wallace
- Date: 2017
- Subjects: English language -- Study and teching (Secondary) -- South Africa Reading -- Study and teching (Secondary) -- South Africa Literacy -- Study and teching (Secondary) -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/249 , vital:19941
- Description: The problem of poor reading skills is a serious one in South Africa, with negative implications for learners’ educational achievement. The failure of learners to read at age- and grade-appropriate levels presents a major challenge to the teaching of reading in South African schools. It is against this background that this study aimed at ascertaining the positive impact of the Reading to Learn methodology in improving the literacy levels of learners in a Grade 10 English First Additional Language classroom in a township school. Reading ability levels were established via a passage extracted from a Grade Platinum English First Additional Learner’s book. Pronunciation and word recognition formed the basis of the reading assessment. Reading translates into writing, so the learners were also assessed in comprehension and creative writing. The results indicated that the learners’ reading abilities were weak, the methodology used to teach reading led to research findings that caused the study to yield findings that suggest that RtL may be the solution to reading problems in the classroom. In addition the study revealed that the ability to read corresponds with cognitive development. The study therefore calls for the adoption of RtL to assist in alleviating reading problems in the classroom.
- Full Text:
- Date Issued: 2017
Understanding the policy-planning-implementation disjuncture: a case study of the Amathole District Municipality, Eastern Cape Province
- Authors: Mhlahlo, Andile
- Date: 2017
- Subjects: Municipal services -- South Africa -- Eastern Cape , Political planning -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Amathole District Municipality (South Africa) -- Planning
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/168521 , vital:41591
- Description: The aim of this study is to investigate why well planned policies are not getting implemented as intended. The study was conducted in the offices of Amathole District Municipality (ADM) in the Eastern Cape Province, including the cooperative project in Alice as one of the projects that was coordinated by the ADM. Concerning the research design and methodology, a qualitative research design was used. The data collection process involved conducting unstructured interviews with the officers from the Amathole District Municipality office (the ADM officers / the municipality officers) and the members of cooperative projects (cooperatives/projects). Mainly, an ethnographic approach was used; it involved embracing participant observation in the ADM offices for approximately 6 months. As the researcher, I participated as one of the ADM’s officers in different activities, namely: attending meetings and one workshop, and accompanying the development officer while conducting an observation of various projects in Butterworth. The findings in the study disclose that the disjuncture between policy planning and implementation may be attributed to 4 factors, which are associated with the ADM office as the development agency for the Amathole region. These are: the incapability to respond to policy implementation complexities, failure to exploit policy implementation complexities as learning opportunities, the insufficient understanding of ‘process monitoring’ as a tool that could be integrated in projects management, as well as the execution of policy implementation in the absence of policy documents as a guide in implementation processes. Moreover, these factors are examined as being related to each other, and they will be discussed in detail in the course of the thesis.
- Full Text:
- Date Issued: 2017
- Authors: Mhlahlo, Andile
- Date: 2017
- Subjects: Municipal services -- South Africa -- Eastern Cape , Political planning -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Amathole District Municipality (South Africa) -- Planning
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/168521 , vital:41591
- Description: The aim of this study is to investigate why well planned policies are not getting implemented as intended. The study was conducted in the offices of Amathole District Municipality (ADM) in the Eastern Cape Province, including the cooperative project in Alice as one of the projects that was coordinated by the ADM. Concerning the research design and methodology, a qualitative research design was used. The data collection process involved conducting unstructured interviews with the officers from the Amathole District Municipality office (the ADM officers / the municipality officers) and the members of cooperative projects (cooperatives/projects). Mainly, an ethnographic approach was used; it involved embracing participant observation in the ADM offices for approximately 6 months. As the researcher, I participated as one of the ADM’s officers in different activities, namely: attending meetings and one workshop, and accompanying the development officer while conducting an observation of various projects in Butterworth. The findings in the study disclose that the disjuncture between policy planning and implementation may be attributed to 4 factors, which are associated with the ADM office as the development agency for the Amathole region. These are: the incapability to respond to policy implementation complexities, failure to exploit policy implementation complexities as learning opportunities, the insufficient understanding of ‘process monitoring’ as a tool that could be integrated in projects management, as well as the execution of policy implementation in the absence of policy documents as a guide in implementation processes. Moreover, these factors are examined as being related to each other, and they will be discussed in detail in the course of the thesis.
- Full Text:
- Date Issued: 2017
Understanding the policy-planning-implementation disjuncture: a case study of the Amathole District Municipality, Eastern Cape Province
- Authors: Mhlahlo, Andile
- Date: 2017
- Subjects: Municipal services -- South Africa -- Eastern Cape , Political planning -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Amathole District Municipality (South Africa) -- Planning
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4422 , vital:20668
- Description: The aim of this study is to investigate why well planned policies are not getting implemented as intended. The study was conducted in the offices of Amathole District Municipality (ADM) in the Eastern Cape Province, including the cooperative project in Alice as one of the projects that was coordinated by the ADM. Concerning the research design and methodology, a qualitative research design was used. The data collection process involved conducting unstructured interviews with the officers from the Amathole District Municipality office (the ADM officers / the municipality officers) and the members of cooperative projects (cooperatives/projects). Mainly, an ethnographic approach was used; it involved embracing participant observation in the ADM offices for approximately 6 months. As the researcher, I participated as one of the ADM’s officers in different activities, namely: attending meetings and one workshop, and accompanying the development officer while conducting an observation of various projects in Butterworth. The findings in the study disclose that the disjuncture between policy planning and implementation may be attributed to 4 factors, which are associated with the ADM office as the development agency for the Amathole region. These are: the incapability to respond to policy implementation complexities, failure to exploit policy implementation complexities as learning opportunities, the insufficient understanding of ‘process monitoring’ as a tool that could be integrated in projects management, as well as the execution of policy implementation in the absence of policy documents as a guide in implementation processes. Moreover, these factors are examined as being related to each other, and they will be discussed in detail in the course of the thesis.
- Full Text:
- Date Issued: 2017
- Authors: Mhlahlo, Andile
- Date: 2017
- Subjects: Municipal services -- South Africa -- Eastern Cape , Political planning -- South Africa -- Eastern Cape , Local government -- South Africa -- Eastern Cape , Amathole District Municipality (South Africa) -- Planning
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/4422 , vital:20668
- Description: The aim of this study is to investigate why well planned policies are not getting implemented as intended. The study was conducted in the offices of Amathole District Municipality (ADM) in the Eastern Cape Province, including the cooperative project in Alice as one of the projects that was coordinated by the ADM. Concerning the research design and methodology, a qualitative research design was used. The data collection process involved conducting unstructured interviews with the officers from the Amathole District Municipality office (the ADM officers / the municipality officers) and the members of cooperative projects (cooperatives/projects). Mainly, an ethnographic approach was used; it involved embracing participant observation in the ADM offices for approximately 6 months. As the researcher, I participated as one of the ADM’s officers in different activities, namely: attending meetings and one workshop, and accompanying the development officer while conducting an observation of various projects in Butterworth. The findings in the study disclose that the disjuncture between policy planning and implementation may be attributed to 4 factors, which are associated with the ADM office as the development agency for the Amathole region. These are: the incapability to respond to policy implementation complexities, failure to exploit policy implementation complexities as learning opportunities, the insufficient understanding of ‘process monitoring’ as a tool that could be integrated in projects management, as well as the execution of policy implementation in the absence of policy documents as a guide in implementation processes. Moreover, these factors are examined as being related to each other, and they will be discussed in detail in the course of the thesis.
- Full Text:
- Date Issued: 2017
Stochastic models in finance
- Authors: Mazengera, Hassan
- Date: 2017
- Subjects: Finance -- Mathematical models , C++ (Computer program language) , GARCH model , Lebesgue-Radon-Nikodym theorems , Radon measures , Stochastic models , Stochastic processes , Stochastic processes -- Computer programs , Martingales (Mathematics) , Pricing -- Mathematical models
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/162724 , vital:40976
- Description: Stochastic models for pricing financial securities are developed. First, we consider the Black Scholes model, which is a classic example of a complete market model and finally focus on Lévy driven models. Jumps may render the market incomplete and are induced in a model by inclusion of a Poisson process. Lévy driven models are more realistic in modelling of asset price dynamics than the Black Scholes model. Martingales are central in pricing, especially of derivatives and we give them the desired attention in the context of pricing. There are an increasing number of important pricing models where analytical solutions are not available hence computational methods come in handy, see Broadie and Glasserman (1997). It is also important to note that computational methods are also applicable to models with analytical solutions. We computationally value selected stochastic financial models using C++. Computational methods are also used to value or price complex financial instruments such as path dependent derivatives. This pricing procedure is applied in the computational valuation of a stochastic (revenue based) loan contract. Derivatives with simple pay of functions and models with analytical solutions are considered for illustrative purposes. The Black-Scholes P.D.E is complex to solve analytically and finite difference methods are widely used. Explicit finite difference scheme is considered in this thesis for computational valuation of derivatives that are modelled by the Black-Scholes P.D.E. Stochastic modelling of asset prices is important for the valuation of derivatives: Gaussian, exponential and gamma variates are simulated for the valuation purposes.
- Full Text:
- Date Issued: 2017
- Authors: Mazengera, Hassan
- Date: 2017
- Subjects: Finance -- Mathematical models , C++ (Computer program language) , GARCH model , Lebesgue-Radon-Nikodym theorems , Radon measures , Stochastic models , Stochastic processes , Stochastic processes -- Computer programs , Martingales (Mathematics) , Pricing -- Mathematical models
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/162724 , vital:40976
- Description: Stochastic models for pricing financial securities are developed. First, we consider the Black Scholes model, which is a classic example of a complete market model and finally focus on Lévy driven models. Jumps may render the market incomplete and are induced in a model by inclusion of a Poisson process. Lévy driven models are more realistic in modelling of asset price dynamics than the Black Scholes model. Martingales are central in pricing, especially of derivatives and we give them the desired attention in the context of pricing. There are an increasing number of important pricing models where analytical solutions are not available hence computational methods come in handy, see Broadie and Glasserman (1997). It is also important to note that computational methods are also applicable to models with analytical solutions. We computationally value selected stochastic financial models using C++. Computational methods are also used to value or price complex financial instruments such as path dependent derivatives. This pricing procedure is applied in the computational valuation of a stochastic (revenue based) loan contract. Derivatives with simple pay of functions and models with analytical solutions are considered for illustrative purposes. The Black-Scholes P.D.E is complex to solve analytically and finite difference methods are widely used. Explicit finite difference scheme is considered in this thesis for computational valuation of derivatives that are modelled by the Black-Scholes P.D.E. Stochastic modelling of asset prices is important for the valuation of derivatives: Gaussian, exponential and gamma variates are simulated for the valuation purposes.
- Full Text:
- Date Issued: 2017
An investigation of how Visual Technology for the Autonomous Learning of Mathematics (VITALmaths) video clips on mobile phones can be used by student teachers as a visualisation tool in the teaching of Number Sense: a case study
- Authors: Kangwa, Lemmy
- Date: 2017
- Subjects: Mathematics -- Study and teaching -- Zambia -- Case studies , Visualization , Number concept , Mobile communication systems in education , Mathematics -- Study and teaching -- Software , Telecommunications in education , Educational innovations , VITALmaths
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/6930 , vital:21201
- Description: Visualisation is increasingly being recognised as having a significant role in the learning of mathematics especially when students are solving mathematical problems (Thornton, 2001). It is argued that visualisation is a powerful tool for learners to construct mental and physical representations that correctly mirror mathematical relationships and concepts. To gain a thorough understanding of the scope of visualisation, three Visual Technology for Autonomous Learning of Mathematics (VITALmaths) (www.vitalmaths.com) video clips were uploaded on mobile phones of each of the eleven participating student teachers who used them in their teaching practice. This is in cognisance of the educational potential offered by mobile phones and their current pervasiveness in the daily lives of both teachers and learners in Zambia (Zambia. Ministry of Education [M.O.E], 2013]). This study sought to investigate how VITALmaths video clips on mobile phones could be used by student teachers as a visualisation tool in the teaching of Number Sense. The videos of the lessons formed the core of my analysis. The study was conducted at four primary schools by eleven student teachers of a public university in Zambia. The study is framed as a case study and is grounded within the interpretive paradigm. The findings revealed that the student teachers’ use of the video clips in the classrooms for teaching was generally approached from two perspectives: at the beginning of the lesson or at the end. The videos were used at the beginning of the lesson as a means to introduce a topic or an idea, and at the end of the lesson to consolidate what was taught. The videos were also used to enhance the conceptual understanding of Number Sense. The findings also revealed that students encountered both enabling and constraining factors in their use of mobile phones to teach number sense. The overall findings revealed that, if well utilised, mobile phones as visualisation tools had the potential to enhance the teaching of Mathematics in general and Number Sense in particular, and therefore teachers should be encouraged to use them in their teaching.
- Full Text:
- Date Issued: 2017
- Authors: Kangwa, Lemmy
- Date: 2017
- Subjects: Mathematics -- Study and teaching -- Zambia -- Case studies , Visualization , Number concept , Mobile communication systems in education , Mathematics -- Study and teaching -- Software , Telecommunications in education , Educational innovations , VITALmaths
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/6930 , vital:21201
- Description: Visualisation is increasingly being recognised as having a significant role in the learning of mathematics especially when students are solving mathematical problems (Thornton, 2001). It is argued that visualisation is a powerful tool for learners to construct mental and physical representations that correctly mirror mathematical relationships and concepts. To gain a thorough understanding of the scope of visualisation, three Visual Technology for Autonomous Learning of Mathematics (VITALmaths) (www.vitalmaths.com) video clips were uploaded on mobile phones of each of the eleven participating student teachers who used them in their teaching practice. This is in cognisance of the educational potential offered by mobile phones and their current pervasiveness in the daily lives of both teachers and learners in Zambia (Zambia. Ministry of Education [M.O.E], 2013]). This study sought to investigate how VITALmaths video clips on mobile phones could be used by student teachers as a visualisation tool in the teaching of Number Sense. The videos of the lessons formed the core of my analysis. The study was conducted at four primary schools by eleven student teachers of a public university in Zambia. The study is framed as a case study and is grounded within the interpretive paradigm. The findings revealed that the student teachers’ use of the video clips in the classrooms for teaching was generally approached from two perspectives: at the beginning of the lesson or at the end. The videos were used at the beginning of the lesson as a means to introduce a topic or an idea, and at the end of the lesson to consolidate what was taught. The videos were also used to enhance the conceptual understanding of Number Sense. The findings also revealed that students encountered both enabling and constraining factors in their use of mobile phones to teach number sense. The overall findings revealed that, if well utilised, mobile phones as visualisation tools had the potential to enhance the teaching of Mathematics in general and Number Sense in particular, and therefore teachers should be encouraged to use them in their teaching.
- Full Text:
- Date Issued: 2017
Exploring Grade 12 Biology teachers’ conceptions, dispositions and pedagogic strategies when mediating learning of evolution in Namibia
- Authors: Katuuo, Henry U
- Date: 2017
- Subjects: Biology teachers -- Attitudes -- Namibia , Biology teachers -- Training of -- Namibia , Evolution -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/13762 , vital:21856
- Description: The Namibian Senior Secondary Certificate Examiners’ Reports (2013) shed light on the topics in which learners often perform poorly and evolution is one of such problematic topics. Anecdotal reasons include religious views of teachers, opposition by learners to the topic, and inadequate understanding of the subject content knowledge. I have not come across any literature on evolution in Namibia that formally look closely at this problem. We do not have a clear idea of what is going on in Namibian science classrooms, when evolution is taught. We do not have a clear idea of the factors at play in the teaching of evolution in these classrooms, either when it is done well and completely or when it is not so. It is against this background that I was inspired to engage in this study which examined teachers’ conceptions, dispositions and pedagogical strategies that they use when teaching evolution. The study is underpinned by an interpretive paradigm, which afforded me an opportunity to understand the teachers’ worldviews in relation to evolution. It also allowed me to gain insight on the pedagogical strategies that teachers use when mediating learning of the topic of evolution and its related concepts. Within the interpretive paradigm, a case study approach was adopted, using a mixed-method design generating both quantitative and qualitative data. Teachers from two regions, namely, the Hardap region and Khomas region, participated in the study. Data were generated using questionnaires, semi-structured interviews and lesson observations. Fifteen questionnaires were completed and from those questionnaires, the sample included six teachers (40%) from the Hardap region while nine teachers (60%) were from the Khomas region. For the interview, the sample included two teachers - one from each region. For the observations, I observed five teachers teaching evolution. I presented quantitative data in tables and graphs, whereas the qualitative data was analysed inductively using Vygotsky’s (1978) socio-cultural theory as a theoretical framework. In addition, I used Ogunniyi’s (2006) Contiguity Argumentative Theory (CAT) as an analytical framework. These theories were used as lenses to interpret and make sense of the qualitative data, which I colour coded to form sub-themes. Thereafter, overlapping sub-themes were combined to form themes, which were linked to the research questions and in relation to literature/theory. Similarly, overlapping themes were combined to form analytical statements. It emerged from the study that religious views did not play a large role in most teachers’ views and attitudes towards the teaching of evolution. Instead, it emerged that lack of content knowledge on evolution is the main factor that influences teachers’ views and attitudes towards teaching evolution in schools. This is quite profound, as the assumption is that when teachers are religious, the likelihood is that they would object to the teaching of evolution. In light of this, the study recommends that there is a need for professional development and support of science teachers, so that they are able to properly mediate the learning of evolution.
- Full Text:
- Date Issued: 2017
- Authors: Katuuo, Henry U
- Date: 2017
- Subjects: Biology teachers -- Attitudes -- Namibia , Biology teachers -- Training of -- Namibia , Evolution -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/13762 , vital:21856
- Description: The Namibian Senior Secondary Certificate Examiners’ Reports (2013) shed light on the topics in which learners often perform poorly and evolution is one of such problematic topics. Anecdotal reasons include religious views of teachers, opposition by learners to the topic, and inadequate understanding of the subject content knowledge. I have not come across any literature on evolution in Namibia that formally look closely at this problem. We do not have a clear idea of what is going on in Namibian science classrooms, when evolution is taught. We do not have a clear idea of the factors at play in the teaching of evolution in these classrooms, either when it is done well and completely or when it is not so. It is against this background that I was inspired to engage in this study which examined teachers’ conceptions, dispositions and pedagogical strategies that they use when teaching evolution. The study is underpinned by an interpretive paradigm, which afforded me an opportunity to understand the teachers’ worldviews in relation to evolution. It also allowed me to gain insight on the pedagogical strategies that teachers use when mediating learning of the topic of evolution and its related concepts. Within the interpretive paradigm, a case study approach was adopted, using a mixed-method design generating both quantitative and qualitative data. Teachers from two regions, namely, the Hardap region and Khomas region, participated in the study. Data were generated using questionnaires, semi-structured interviews and lesson observations. Fifteen questionnaires were completed and from those questionnaires, the sample included six teachers (40%) from the Hardap region while nine teachers (60%) were from the Khomas region. For the interview, the sample included two teachers - one from each region. For the observations, I observed five teachers teaching evolution. I presented quantitative data in tables and graphs, whereas the qualitative data was analysed inductively using Vygotsky’s (1978) socio-cultural theory as a theoretical framework. In addition, I used Ogunniyi’s (2006) Contiguity Argumentative Theory (CAT) as an analytical framework. These theories were used as lenses to interpret and make sense of the qualitative data, which I colour coded to form sub-themes. Thereafter, overlapping sub-themes were combined to form themes, which were linked to the research questions and in relation to literature/theory. Similarly, overlapping themes were combined to form analytical statements. It emerged from the study that religious views did not play a large role in most teachers’ views and attitudes towards the teaching of evolution. Instead, it emerged that lack of content knowledge on evolution is the main factor that influences teachers’ views and attitudes towards teaching evolution in schools. This is quite profound, as the assumption is that when teachers are religious, the likelihood is that they would object to the teaching of evolution. In light of this, the study recommends that there is a need for professional development and support of science teachers, so that they are able to properly mediate the learning of evolution.
- Full Text:
- Date Issued: 2017
The medical profession and the universalisation of South African Health Care: analysing the response of Eastern Cape general practitioners to the National Health Insurance proposals
- Authors: Hannah, Bridget
- Date: 2017
- Subjects: Health insurance -- South Africa , Health insurance -- Government policy -- South Africa , Medical care, Cost of -- South Africa , National health insurance -- South Africa , Medical policy -- South Africa , Physicians -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6075 , vital:21029
- Description: In 2011, the Green Paper on National Health Insurance (NHI) in South Africa was released, committing the South African government to a 14-year plan to radically transform the currently inequitable health system towards providing comprehensive quality health care free at point of access to all citizens. The pursuit of universal health coverage (UHC) in South Africa forms part of a global aspiration to achieve more equitable healthcare delivery. One of the critical issues emerging from the Green Paper was how the NHI would be staffed. The NHI is unlikely to be adequately staffed without GPs but evidence suggests that private sector doctors have always been resistant to nationalisation or socialisation as a threat to their occupational power and professional status. The core work of this thesis is a study undertaken of 78 doctors in the Eastern Cape, focusing on private sector general practitioners (GPs), as the largest constituency of medical professionals in the country. The interview schedule was designed to gauge doctors' responses to the NHI, encourage discussion on their reactions to the reforms, and its implications in their view for private medical practice. The responses of the doctors are analysed through application of two theoretical themes, namely: (i) actor-centred policy creation, discussed through application of Walt and Gilson's (1994) shared focus on content, context, process and actors in the policy process, and (ii) the debate on medical professionalism, espoused by Freidson (1973, 1994) and argued against by Haug and Sussman (1969), and McKinlay (1972, 1993). Thus, if the process of policy making must take into account key actors in order to deliver a successful policy transition, what are the implications if these actors are actively excluded, or do not willingly cooperate? Does this indicate anything telling about the private sector's role to play in the pursuit of universal healthcare?
- Full Text:
- Date Issued: 2017
- Authors: Hannah, Bridget
- Date: 2017
- Subjects: Health insurance -- South Africa , Health insurance -- Government policy -- South Africa , Medical care, Cost of -- South Africa , National health insurance -- South Africa , Medical policy -- South Africa , Physicians -- South Africa -- Attitudes
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/6075 , vital:21029
- Description: In 2011, the Green Paper on National Health Insurance (NHI) in South Africa was released, committing the South African government to a 14-year plan to radically transform the currently inequitable health system towards providing comprehensive quality health care free at point of access to all citizens. The pursuit of universal health coverage (UHC) in South Africa forms part of a global aspiration to achieve more equitable healthcare delivery. One of the critical issues emerging from the Green Paper was how the NHI would be staffed. The NHI is unlikely to be adequately staffed without GPs but evidence suggests that private sector doctors have always been resistant to nationalisation or socialisation as a threat to their occupational power and professional status. The core work of this thesis is a study undertaken of 78 doctors in the Eastern Cape, focusing on private sector general practitioners (GPs), as the largest constituency of medical professionals in the country. The interview schedule was designed to gauge doctors' responses to the NHI, encourage discussion on their reactions to the reforms, and its implications in their view for private medical practice. The responses of the doctors are analysed through application of two theoretical themes, namely: (i) actor-centred policy creation, discussed through application of Walt and Gilson's (1994) shared focus on content, context, process and actors in the policy process, and (ii) the debate on medical professionalism, espoused by Freidson (1973, 1994) and argued against by Haug and Sussman (1969), and McKinlay (1972, 1993). Thus, if the process of policy making must take into account key actors in order to deliver a successful policy transition, what are the implications if these actors are actively excluded, or do not willingly cooperate? Does this indicate anything telling about the private sector's role to play in the pursuit of universal healthcare?
- Full Text:
- Date Issued: 2017
Chemical composition of leaf essential oils of Lantana camara varieties in South Africa and their effect on the behavioural preference of Falconia intermedia
- Authors: Ngxande-Koza, Samella W
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4877 , vital:20739
- Description: Lantana camara L. (Verbenaceae) is one the most problematic invaders in South Africa invading forest edges, sand dunes, and shorelines by forming impenetrable thickets. Lantana camara invasions degrade natural biodiversity, reduce the value of land and consequently it has been a target for biological control, over the last 50 years in South Africa. Studies that have reported on chemical profile of Lantana camara have been conducted around the world but not in South Africa. Hence, the first aim of the current study was to identify the chemical baseline of L. camara varieties in the Eastern Cape, South Africa. Recent studies have shown that feeding by one of the agents released against L. camara, Falconia intermedia (Distant) (Hemiptera: Miridae), induces anti-herbivory response through increased leaf toughness and trichome density. A preliminary study conducted also reported the production of volatile chemicals by one variety, Whitney Farm, due to feeding by the mirids. Therefore, the second aim was to determine the induced changes in chemical compounds of L. camara varieties after feeding by F. intermedia. A third aim was to determine the effect these chemical compounds have on the behaviour of F. intermedia. To identify the chemical baseline of L. camara varieties, the essential oils of four L. camara varieties (East London, Port Alfred, Whitney Farm and Heather Glen) were analysed using gas chromatography mass spectrometry (GC-MS) and that resulted to the identification of 163 constitutive and 75 induced chemicals across the varieties tested. Lantana camara varieties showed different chemical classes but were highly dominated by terpenes. A great variation in the number of constitutive chemical compounds was found in all the varieties. There were 56 constitutive chemical compounds in the Whitney Farm variety, 41 in the East London variety, 36 in the Heather Glen variety and 30 in the Port Alfred variety. The Whitney Farm variety had the highest number (22) of unique constitutive chemicals identified when compared with other varieties. This indicates the chemical distinctiveness of the Whitney Farm variety from the other varieties. In the varieties tested, there were common chemical compounds identified in constitutive and induced (discussed below) states of the plants such as caryophyllene, hexane, naphthalene, copaene and a-caryophyllene. Besides naphthalene, the majority of chemical compounds in South African L. camara varieties were similar to compounds that have been identified across the world, suggesting that they are closely related. The expression of naphthalene in these varieties may be due to changes in the chemicals expressed over evolutionary time as predicted by the Novel Weapons Hypothesis. Amongst the varieties, a great variation in chemical compounds and their concentrations was shown in the induced states of the plants. The concentration of constitutive caryophyllene ranged from (3.13 - 15.7) %, to (4.02 - 11.10) % after feeding. The concentration of constitutive hexane ranged from (6.13 - 71.19) %, to (33.3 - 75.8) % after feeding. The concentration of constitutive naphthalene ranged from (0.21 - 4.79) %, to (0.92 - 2.11) % after feeding. The concentration of constitutive copaene ranged from (0.57 - 1.57) %, to (1.20 - 2.72) %. Lastly, the concentration of constitutive a-caryophyllene ranged from (1.18 - 9.03) %, to (0.78 - 5.48) % after feeding. The changes in chemical concentrations in lantana varieties indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. To determine the effect of the identified compounds on the behaviour of F. intermedia adults, olfactometer bioassays were conducted using a Y-tube technique. A significantly higher proportion of F. intermedia were attracted to undamaged leaves over damaged leaves and purified air. Undamaged leaves attracted 52 % of F. intermedia from the East London variety, 62.5 % from the Port Alfred variety, 56 % from the Whitney Farm variety, 58 % from the Lyndhurst variety and 54.5 % from the Heather Glen variety in dual choice trials versus damaged leaves. Furthermore, a significantly higher proportion of F. intermedia were attracted to damaged leaves over purified air. Damaged leaves attracted 67 % of F. intermedia from the East London variety, 67 % from the Port Alfred variety, 65.9 % from the Whitney Farm variety, 65.3 % from the Heather Glen variety and 64.5 % from the Lyndhurst variety. Olfactometer bioassays were also conducted using purified standard compounds of four chemical compounds identified from essential oils, hexane was used as a positive control as it is reported to be an insect attractant in literature. Hexane was highly attractive to the mirids compared to three standard compounds caryophyllene, caryophyllene oxide and naphthalene at the rate of 80 %, 73 % and 80 %, respectively. The standard compounds tested against F. intermedia are major compounds contained by L. camara varieties and they have proven to have a repellent effect. This may indicate that after feeding by F. intermedia, the major compounds expressed by the plant varieties repel F. intermedia contributing to the invasiveness of this weed. The increased expression of hexane and caryophyllene after feeding may also indicate increased attraction to some insects, opening up the potential for third trophic level interactions in varieties where this is the case. This is the first study on the chemical composition of essential oils of L. camara in South Africa. Therefore, we recommend that where appropriate chemical profile studies of the invasive alien plants should be considered during host specificity testing, and the vital role of chemical compounds on agent-weed interactions must be taken into consideration with other factors before and after the biological control agents are released.
- Full Text:
- Date Issued: 2017
- Authors: Ngxande-Koza, Samella W
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4877 , vital:20739
- Description: Lantana camara L. (Verbenaceae) is one the most problematic invaders in South Africa invading forest edges, sand dunes, and shorelines by forming impenetrable thickets. Lantana camara invasions degrade natural biodiversity, reduce the value of land and consequently it has been a target for biological control, over the last 50 years in South Africa. Studies that have reported on chemical profile of Lantana camara have been conducted around the world but not in South Africa. Hence, the first aim of the current study was to identify the chemical baseline of L. camara varieties in the Eastern Cape, South Africa. Recent studies have shown that feeding by one of the agents released against L. camara, Falconia intermedia (Distant) (Hemiptera: Miridae), induces anti-herbivory response through increased leaf toughness and trichome density. A preliminary study conducted also reported the production of volatile chemicals by one variety, Whitney Farm, due to feeding by the mirids. Therefore, the second aim was to determine the induced changes in chemical compounds of L. camara varieties after feeding by F. intermedia. A third aim was to determine the effect these chemical compounds have on the behaviour of F. intermedia. To identify the chemical baseline of L. camara varieties, the essential oils of four L. camara varieties (East London, Port Alfred, Whitney Farm and Heather Glen) were analysed using gas chromatography mass spectrometry (GC-MS) and that resulted to the identification of 163 constitutive and 75 induced chemicals across the varieties tested. Lantana camara varieties showed different chemical classes but were highly dominated by terpenes. A great variation in the number of constitutive chemical compounds was found in all the varieties. There were 56 constitutive chemical compounds in the Whitney Farm variety, 41 in the East London variety, 36 in the Heather Glen variety and 30 in the Port Alfred variety. The Whitney Farm variety had the highest number (22) of unique constitutive chemicals identified when compared with other varieties. This indicates the chemical distinctiveness of the Whitney Farm variety from the other varieties. In the varieties tested, there were common chemical compounds identified in constitutive and induced (discussed below) states of the plants such as caryophyllene, hexane, naphthalene, copaene and a-caryophyllene. Besides naphthalene, the majority of chemical compounds in South African L. camara varieties were similar to compounds that have been identified across the world, suggesting that they are closely related. The expression of naphthalene in these varieties may be due to changes in the chemicals expressed over evolutionary time as predicted by the Novel Weapons Hypothesis. Amongst the varieties, a great variation in chemical compounds and their concentrations was shown in the induced states of the plants. The concentration of constitutive caryophyllene ranged from (3.13 - 15.7) %, to (4.02 - 11.10) % after feeding. The concentration of constitutive hexane ranged from (6.13 - 71.19) %, to (33.3 - 75.8) % after feeding. The concentration of constitutive naphthalene ranged from (0.21 - 4.79) %, to (0.92 - 2.11) % after feeding. The concentration of constitutive copaene ranged from (0.57 - 1.57) %, to (1.20 - 2.72) %. Lastly, the concentration of constitutive a-caryophyllene ranged from (1.18 - 9.03) %, to (0.78 - 5.48) % after feeding. The changes in chemical concentrations in lantana varieties indicated that feeding by the mirid on L. camara varieties causes an induction by either reducing or increasing the chemical concentrations. To determine the effect of the identified compounds on the behaviour of F. intermedia adults, olfactometer bioassays were conducted using a Y-tube technique. A significantly higher proportion of F. intermedia were attracted to undamaged leaves over damaged leaves and purified air. Undamaged leaves attracted 52 % of F. intermedia from the East London variety, 62.5 % from the Port Alfred variety, 56 % from the Whitney Farm variety, 58 % from the Lyndhurst variety and 54.5 % from the Heather Glen variety in dual choice trials versus damaged leaves. Furthermore, a significantly higher proportion of F. intermedia were attracted to damaged leaves over purified air. Damaged leaves attracted 67 % of F. intermedia from the East London variety, 67 % from the Port Alfred variety, 65.9 % from the Whitney Farm variety, 65.3 % from the Heather Glen variety and 64.5 % from the Lyndhurst variety. Olfactometer bioassays were also conducted using purified standard compounds of four chemical compounds identified from essential oils, hexane was used as a positive control as it is reported to be an insect attractant in literature. Hexane was highly attractive to the mirids compared to three standard compounds caryophyllene, caryophyllene oxide and naphthalene at the rate of 80 %, 73 % and 80 %, respectively. The standard compounds tested against F. intermedia are major compounds contained by L. camara varieties and they have proven to have a repellent effect. This may indicate that after feeding by F. intermedia, the major compounds expressed by the plant varieties repel F. intermedia contributing to the invasiveness of this weed. The increased expression of hexane and caryophyllene after feeding may also indicate increased attraction to some insects, opening up the potential for third trophic level interactions in varieties where this is the case. This is the first study on the chemical composition of essential oils of L. camara in South Africa. Therefore, we recommend that where appropriate chemical profile studies of the invasive alien plants should be considered during host specificity testing, and the vital role of chemical compounds on agent-weed interactions must be taken into consideration with other factors before and after the biological control agents are released.
- Full Text:
- Date Issued: 2017
Beyond War, Violence, and Suffering: Everyday Life in the Honde Valley Borderland Communities during Zimbabwe’s Liberation War and the RENAMO Insurgency, c.1960-2016
- Authors: Nyachega, Nicholas
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7023 , vital:21210
- Description: This thesis examines the history of the Honde Valley area, in Mutasa District, along the Zimbabwe-Mozambique border. It uses two historic developments: the Zimbabwe liberation war and RENAMO insurgency to explore daily life and mundane experiences of the borderland communities, mainly from the late 1970s to 2016. Because earlier historians of these two historic developments have been much interested in studying the aspects of violence and suffering, this study extends the focus of analysis to the mundane experiences. I argue that in borderland areas, there are other wartime aspects of life worth investigating other than violence and suffering. In doing so, the thesis deploys the notions of conviviality and the everyday to understand the daily experiences of the Honde Valley communities during the disruptions caused to everyday life by these wars. Admittedly, twentieth century wars in Zimbabwe and Mozambique transformed the area that had previously remained at the fringes of colonial power from 1890-1950, into a new and bitterly contested ‘sharp end’ of the war. Nonetheless, peoples’ experiences during these wars cannot be understood merely in relation to violence and suffering. Furthermore, I argue that although some families were forcibly moved into liberation war “Protected Villages ”, they innovatively designed new mechanisms and alternative lifestyles in response to the state’s routinised control. The thesis concludes that beyond the confines of war-induced violence and suffering, Honde Valley communities used their borderland location to evade the pressures of war and continued with life.
- Full Text:
- Date Issued: 2017
- Authors: Nyachega, Nicholas
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7023 , vital:21210
- Description: This thesis examines the history of the Honde Valley area, in Mutasa District, along the Zimbabwe-Mozambique border. It uses two historic developments: the Zimbabwe liberation war and RENAMO insurgency to explore daily life and mundane experiences of the borderland communities, mainly from the late 1970s to 2016. Because earlier historians of these two historic developments have been much interested in studying the aspects of violence and suffering, this study extends the focus of analysis to the mundane experiences. I argue that in borderland areas, there are other wartime aspects of life worth investigating other than violence and suffering. In doing so, the thesis deploys the notions of conviviality and the everyday to understand the daily experiences of the Honde Valley communities during the disruptions caused to everyday life by these wars. Admittedly, twentieth century wars in Zimbabwe and Mozambique transformed the area that had previously remained at the fringes of colonial power from 1890-1950, into a new and bitterly contested ‘sharp end’ of the war. Nonetheless, peoples’ experiences during these wars cannot be understood merely in relation to violence and suffering. Furthermore, I argue that although some families were forcibly moved into liberation war “Protected Villages ”, they innovatively designed new mechanisms and alternative lifestyles in response to the state’s routinised control. The thesis concludes that beyond the confines of war-induced violence and suffering, Honde Valley communities used their borderland location to evade the pressures of war and continued with life.
- Full Text:
- Date Issued: 2017
Lizalise Idinga Lakho [Honour Thy Promise]: The Methodist Church Women’s Manyano, the Bifurcated Public Sphere, Divine Strength, Ubufazi and Motherhood in Post-Apartheid South Africa
- Authors: Ngcobozi, Lihle
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/17717 , vital:22271
- Description: This study examines the socio-political role of the Christian church based women’s Manyano organisations in post-apartheid South Africa. Specifically, the study examines the ways in which the women’s Manyano organisations offer black women a site for the performance of citizenship. The study is based on life history interviews conducted with seventeen members of the Methodist Church Women’s Manyano of the Lamontville Circuit in Kwa-Zulu Natal. The study shows that dominant literature on Manyano women is primarily located in the historiography of the formation of Manyano groups within the historical development of the black church from the moment of missionary contact in South Africa. This literature shows that the missionaries used the coming together of black women in the church to promote ideas of devout domesticity that are based on Anglophone Victorian womanhood. This literature also shows that the structural constraints of colonisation and apartheid transformed the black church into a counterpublic space which focused largely on the liberation of the black majority from political, economic, and social exclusion from the colonial and apartheid public sphere. These constraints also transformed the role of women’s Manyano organisations to become an important space from which black women came to resist and defeat apartheid. This study shows that this historical framing of women’s Manyano groups has shaped their role in post-apartheid South Africa. Located in the African feminist theory, the study argues that Manyano women’s publicness is not limited to gendered expressions of the public and private sphere. Instead, Manyano women demonstrate that their publicness in post-apartheid South Africa ought to be understood through a combination of the varied identities that they straddle, such as those of a politically and culturally defined womanhood and communally based motherhood, which express their understanding and performance of citizenship. The thesis, therefore, argues that the contemporary role and functioning of Manyanos is located within both the hegemonic public sphere that is granted by the civil liberties of the new South Africa, and the historical black bifurcated counterpublic -which combined offer black women the ability to devise strategies to confront present-day socioeconomic challenges such as structural poverty that shapes the lives of the majority of black women in post-apartheid South Africa. The study contributes, therefore, to the reconstruction of the concept of the public sphere through the use of Manyano women’s dynamic position in post-apartheid South Africa. It shows that the dualist nature of Manyano women’s position and identity allows for a multifaceted approach in the understanding of citizenship for Manyano women today. Furthermore, and importantly, the study shows that the complex roles that Manyano women navigate within the different spheres complicate the interpretations of womanhood and motherhood as understood in dominant (white western) feminist theory in ways that often lead to the delegitimisation and erasure of Manyano women’s contributions to ideas about post-apartheid feminisms.
- Full Text:
- Date Issued: 2017
- Authors: Ngcobozi, Lihle
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/17717 , vital:22271
- Description: This study examines the socio-political role of the Christian church based women’s Manyano organisations in post-apartheid South Africa. Specifically, the study examines the ways in which the women’s Manyano organisations offer black women a site for the performance of citizenship. The study is based on life history interviews conducted with seventeen members of the Methodist Church Women’s Manyano of the Lamontville Circuit in Kwa-Zulu Natal. The study shows that dominant literature on Manyano women is primarily located in the historiography of the formation of Manyano groups within the historical development of the black church from the moment of missionary contact in South Africa. This literature shows that the missionaries used the coming together of black women in the church to promote ideas of devout domesticity that are based on Anglophone Victorian womanhood. This literature also shows that the structural constraints of colonisation and apartheid transformed the black church into a counterpublic space which focused largely on the liberation of the black majority from political, economic, and social exclusion from the colonial and apartheid public sphere. These constraints also transformed the role of women’s Manyano organisations to become an important space from which black women came to resist and defeat apartheid. This study shows that this historical framing of women’s Manyano groups has shaped their role in post-apartheid South Africa. Located in the African feminist theory, the study argues that Manyano women’s publicness is not limited to gendered expressions of the public and private sphere. Instead, Manyano women demonstrate that their publicness in post-apartheid South Africa ought to be understood through a combination of the varied identities that they straddle, such as those of a politically and culturally defined womanhood and communally based motherhood, which express their understanding and performance of citizenship. The thesis, therefore, argues that the contemporary role and functioning of Manyanos is located within both the hegemonic public sphere that is granted by the civil liberties of the new South Africa, and the historical black bifurcated counterpublic -which combined offer black women the ability to devise strategies to confront present-day socioeconomic challenges such as structural poverty that shapes the lives of the majority of black women in post-apartheid South Africa. The study contributes, therefore, to the reconstruction of the concept of the public sphere through the use of Manyano women’s dynamic position in post-apartheid South Africa. It shows that the dualist nature of Manyano women’s position and identity allows for a multifaceted approach in the understanding of citizenship for Manyano women today. Furthermore, and importantly, the study shows that the complex roles that Manyano women navigate within the different spheres complicate the interpretations of womanhood and motherhood as understood in dominant (white western) feminist theory in ways that often lead to the delegitimisation and erasure of Manyano women’s contributions to ideas about post-apartheid feminisms.
- Full Text:
- Date Issued: 2017
An analysis of flood activity over the past century based on the sedimentary deposits in the Mfolozi floodplain
- Authors: Mbao, Chabala
- Date: 2017
- Subjects: Floodplain morphology -- South Africa -- Mfolozi River , Floodplains -- South Africa -- Kwazulu-Natal , Sedimentation and deposition -- South Africa -- Kwazulu-Natal , Floods -- South Africa -- Kwazulu-Natal -- Measurement , Hydrology -- Research -- South Africa -- Kwazulu-Natal , Stream measurements -- South Africa -- Kwazulu-Natal
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/53711 , vital:26312
- Description: Floods are natural phenomena that are of widespread interest to the scientific community, particularly in the context of understanding the impact of climate change as well as changing land use patterns and the security of infrastructure such as towns and roads. In northern KwaZulu-Natal, large flood events have been a reoccurring feature over the past century. The geographical position and extent of the region means that is affected by both inland and coastal weather phenomena, each with the potential to cause large flood events. While information pertaining to large floods in the region in the form of flow data is readily available, flow data is often incomplete and limited in terms of how far back in time the records extend. The Mfolozi River floodplain itself also houses a record of flood activity in the region in the form of sedimentary deposits, which have the potential to reveal flood activity over a much longer timescale, even when monitoring of flood activity in the region was not present. Establishing a link between the hydrological and sedimentary features of floods may be useful in establishing a record of flood activity extending beyond the limits of historical records. The aim of this project was to construct a record of major flood events on the Mfolozi River floodplain over the last century and determine their source. The first objective involved establishing the history of flood events in the Mfolozi River catchment utilising hydrological data recorded throughout the catchment. Thirty nine different large floods (defined as being over 800 m3.s-1) were recorded on the floodplain over the past century. The data also highlighted differences in the extent of known coastal and inland systems (tropical cyclones and cut-off lows respectively), allowing for inferences to be made about the area of the catchment most likely affected by each event; some flood events were identified as having mostly affected the upper reaches of the catchment, while others mostly affected the lower reaches, closer to the coast. The second objective was to identify the various physical, mineralogical and geochemical features of the sediment deposited on the Mfolozi floodplain. Multiple individual flood deposits were identified in the sedimentary record, with sediment tracing analysis providing insight into the source of the deposits within the catchment; no traces of igneous or metamorphic material could be found within the sediment. The source rocks were identified as mostly quartzite, with minor shale and sandstone deposits as well. This put the source of the sediment in the upper to middle reaches of the catchment. The sedimentary analysis was combined with the hydrological records to establish a chronology of flood events extending back to the 1960's. Unfortunately, this record could not be extended further due to the limited amount of sediment collected as well the limits of readily available analytical techniques; radionuclide dating methods were unsuccessful due to the low amounts of fallout radionuclides present in the sediment. The study has however successfully established a history of flood events in the region, as well as providing a link between the hydrological and sedimentary features of flood events that could potentially be useful for current and future research.
- Full Text:
- Date Issued: 2017
- Authors: Mbao, Chabala
- Date: 2017
- Subjects: Floodplain morphology -- South Africa -- Mfolozi River , Floodplains -- South Africa -- Kwazulu-Natal , Sedimentation and deposition -- South Africa -- Kwazulu-Natal , Floods -- South Africa -- Kwazulu-Natal -- Measurement , Hydrology -- Research -- South Africa -- Kwazulu-Natal , Stream measurements -- South Africa -- Kwazulu-Natal
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/53711 , vital:26312
- Description: Floods are natural phenomena that are of widespread interest to the scientific community, particularly in the context of understanding the impact of climate change as well as changing land use patterns and the security of infrastructure such as towns and roads. In northern KwaZulu-Natal, large flood events have been a reoccurring feature over the past century. The geographical position and extent of the region means that is affected by both inland and coastal weather phenomena, each with the potential to cause large flood events. While information pertaining to large floods in the region in the form of flow data is readily available, flow data is often incomplete and limited in terms of how far back in time the records extend. The Mfolozi River floodplain itself also houses a record of flood activity in the region in the form of sedimentary deposits, which have the potential to reveal flood activity over a much longer timescale, even when monitoring of flood activity in the region was not present. Establishing a link between the hydrological and sedimentary features of floods may be useful in establishing a record of flood activity extending beyond the limits of historical records. The aim of this project was to construct a record of major flood events on the Mfolozi River floodplain over the last century and determine their source. The first objective involved establishing the history of flood events in the Mfolozi River catchment utilising hydrological data recorded throughout the catchment. Thirty nine different large floods (defined as being over 800 m3.s-1) were recorded on the floodplain over the past century. The data also highlighted differences in the extent of known coastal and inland systems (tropical cyclones and cut-off lows respectively), allowing for inferences to be made about the area of the catchment most likely affected by each event; some flood events were identified as having mostly affected the upper reaches of the catchment, while others mostly affected the lower reaches, closer to the coast. The second objective was to identify the various physical, mineralogical and geochemical features of the sediment deposited on the Mfolozi floodplain. Multiple individual flood deposits were identified in the sedimentary record, with sediment tracing analysis providing insight into the source of the deposits within the catchment; no traces of igneous or metamorphic material could be found within the sediment. The source rocks were identified as mostly quartzite, with minor shale and sandstone deposits as well. This put the source of the sediment in the upper to middle reaches of the catchment. The sedimentary analysis was combined with the hydrological records to establish a chronology of flood events extending back to the 1960's. Unfortunately, this record could not be extended further due to the limited amount of sediment collected as well the limits of readily available analytical techniques; radionuclide dating methods were unsuccessful due to the low amounts of fallout radionuclides present in the sediment. The study has however successfully established a history of flood events in the region, as well as providing a link between the hydrological and sedimentary features of flood events that could potentially be useful for current and future research.
- Full Text:
- Date Issued: 2017
An analysis of the impact of financialization on commodity markets
- Authors: Ndawona, Takudzwa Maitaishe
- Date: 2017
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/7113 , vital:21218
- Description: An unprecedented increase in real commodity prices from 2002-2011 fuelled an intense debate as to the causes of the steep rise in prices and its possible implications for producers and consumers. On the one hand, the prolonged and dramatic rise in almost all commodity prices is attributed to growing demand from emerging market economies, supply shocks such as adverse weather conditions, export bans as well as other macroeconomic factors. Collectively these are known as the fundamental (demand and supply) factors. On the other hand, there is a growing body of evidence that suggests these fundamental factors alone are not sufficient enough to explain recent commodity price developments. It is noted that alongside changes in the fundamental factors, there was a major shift in trading activities on commodity derivative markets related to the increasing presence of financial investors, institutional investors and hedge funds. This had important effects, it is argued, on the microstructure of these markets and on price dynamics in a process termed “fmancialization”. Most of the empirical literature covers the period of rising commodity prices from 20022011. This study seeks to add to the existing literature by examining, in addition, the impact of financialization when commodity prices were falling from 2011-2015. Whereas the literature focuses mainly on the rise of agricultural commodity prices, the focus of this study is on metals, oil and bulk commodities (coal and iron ore). Two techniques are employed, namely the calculation of rolling correlations for futures and spot returns. Granger causality tests are then performed to examine the relationships between futures and spot prices. Rolling return correlations are calculated for i) different exchange- traded commodities and ii) exchange-traded commodities and bulk commodities not traded on exchanges. This is done to establish whether the increased correlations between different commodities found in the literature still hold now that commodity prices across all categories are falling. Granger causality tests are used in order to establish the link between the futures prices and spot prices both during the upswing period (2002-2011) and downswing period (2011-2015). It is found that rapidly growing indexed-based investment in commodity markets (financialization) during the upswing period is concurrent with increasingly correlated returns on the prices of unrelated commodities in both the futures and spot markets. These correlations decline during the period of falling commodity prices (2011-2015). This was a period in which the total amount of commodity assets under management fell sharply. This supports the a priori expectation that if the increased correlations of previously seemingly correlated and unrelated commodities during the upswing had been driven by financialization, the correlation would decline in the downturn. Granger causality results reveal statistically significant evidence of futures prices (returns) driving spot prices (returns) during the financialization period. However, post-financialization there is a shift to more bidirectional relationships. The study therefore concludes that, in addition to changing fundamental and macroeconomic factors, the financialization of commodity markets further drove the excessive and volatile price levels in commodity markets from 2002 to 2011.
- Full Text:
- Date Issued: 2017
- Authors: Ndawona, Takudzwa Maitaishe
- Date: 2017
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/7113 , vital:21218
- Description: An unprecedented increase in real commodity prices from 2002-2011 fuelled an intense debate as to the causes of the steep rise in prices and its possible implications for producers and consumers. On the one hand, the prolonged and dramatic rise in almost all commodity prices is attributed to growing demand from emerging market economies, supply shocks such as adverse weather conditions, export bans as well as other macroeconomic factors. Collectively these are known as the fundamental (demand and supply) factors. On the other hand, there is a growing body of evidence that suggests these fundamental factors alone are not sufficient enough to explain recent commodity price developments. It is noted that alongside changes in the fundamental factors, there was a major shift in trading activities on commodity derivative markets related to the increasing presence of financial investors, institutional investors and hedge funds. This had important effects, it is argued, on the microstructure of these markets and on price dynamics in a process termed “fmancialization”. Most of the empirical literature covers the period of rising commodity prices from 20022011. This study seeks to add to the existing literature by examining, in addition, the impact of financialization when commodity prices were falling from 2011-2015. Whereas the literature focuses mainly on the rise of agricultural commodity prices, the focus of this study is on metals, oil and bulk commodities (coal and iron ore). Two techniques are employed, namely the calculation of rolling correlations for futures and spot returns. Granger causality tests are then performed to examine the relationships between futures and spot prices. Rolling return correlations are calculated for i) different exchange- traded commodities and ii) exchange-traded commodities and bulk commodities not traded on exchanges. This is done to establish whether the increased correlations between different commodities found in the literature still hold now that commodity prices across all categories are falling. Granger causality tests are used in order to establish the link between the futures prices and spot prices both during the upswing period (2002-2011) and downswing period (2011-2015). It is found that rapidly growing indexed-based investment in commodity markets (financialization) during the upswing period is concurrent with increasingly correlated returns on the prices of unrelated commodities in both the futures and spot markets. These correlations decline during the period of falling commodity prices (2011-2015). This was a period in which the total amount of commodity assets under management fell sharply. This supports the a priori expectation that if the increased correlations of previously seemingly correlated and unrelated commodities during the upswing had been driven by financialization, the correlation would decline in the downturn. Granger causality results reveal statistically significant evidence of futures prices (returns) driving spot prices (returns) during the financialization period. However, post-financialization there is a shift to more bidirectional relationships. The study therefore concludes that, in addition to changing fundamental and macroeconomic factors, the financialization of commodity markets further drove the excessive and volatile price levels in commodity markets from 2002 to 2011.
- Full Text:
- Date Issued: 2017
Browsing as a demographic bottleneck in a semi-arid savanna: the effect of size and age on compensatory responses of Vachellia karroo seedlings after simulated herbivory
- Authors: Perumal, Lavinia
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4899 , vital:20741
- Description: Savannas are characterised by a continuous grass layer with scattered trees at varying densities. This vegetation structure is determined by several interacting factors, including fire, herbivory, resource competition and atmospheric CO2 concentration. The preservation of savanna biomes is important and a shift towards a woody biome threatens savanna globally. Bush encroachment which describes the shift towards domination of savannas by C3 woody plants, is especially acute in southern Africa. In semi-arid rangelands, encroachment progresses to dense thickets dominated by thorny and unpalatable bushes and trees. There is evidence that bush encroachment is driven by a reduction in fire and browsing events as well as their interaction. Despite browsing having strong effects on African savannas its isolated role in maintaining tree-grass coexistence has not received as much attention as the role of fire. Therefore the overall aim of this study was to examine the effects of browsing on seedlings of a commonly encroaching species, Vachellia karroo. Browsing was hypothesized to be a demographic release bottleneck for bush encroachment in a semiarid (MAP ~550mm) savanna in the Eastern Cape of South Africa, where fire has been historically rare. In a single study I explored the fate of V. karroo seedlings (less than a year old) following browsing in sub canopy and inter canopy microhabitats. Additionally, I explored how the fate of a seedling changed under high and low tree cover. Firstly, I investigated the type, intensity and frequency of herbivory, from both small and large herbivores, which seedlings were subjected to. Results revealed that browsing was severe and frequent with the majority of seedlings browsed more than twice over a 12 month period. Large browsers such as kudu and impala caused high seedling mortality (46%) while smaller browsers such as invertebrates were more effective at suppressing growth. Microhabitat had little impact on seedling survival, but significantly influenced plant compensatory growth. Reduced seedling growth following browsing was observed in the sub-canopy in comparison to seedling growth in full sunlight in the intercanopy, suggesting V.karroo may be shade intolerant. Secondly, the effect of tree cover on browsed seedlings was determined by quantifying browsing frequency and intensity at high and low tree cover. No differences in browsing intensity and frequency were observed between high and low tree cover. However, high tree cover due to bush encroachment limited seedling above ground growth. The aim of the second study was to investigate how V.karroo survival and growth were influenced by its age and size following simulated browsing. I explored this aim through field and greenhouse experiments. I was particularly interested in testing how plant sensitivity to varying defoliation intensities of repeated browsing varied with plant age (known ages of 6, 12, 16 and 30 weeks). There were large differences in mortality between the different age groups. Furthermore, age interacted with repeated browsing and negatively influenced seedling survival and regrowth. Older seedlings (16 and 30 week old) had greater survival and higher browsing frequencies resulted in greater mortality and reduced growth. The threshold age after which seedlings become more tolerant to herbivory occurs at an age of 28 weeks. Seedlings less than six weeks old experiencing intense (100 % defoliation)browsing had a very low probability (33%) of survival following just a single defoliation. Interestingly, all 16 week old seedlings regrew most of their foliage following a moderate (50%) defoliation with some plants overcompensating for leaf loss. The field study revealed two distinct demographic stages based on age and size (seedlings< 9 mm and saplings >9 mm in stem basal diameter (SBD)). Browsing had a strong negative effect on seedlings, resulting in reduced investment in leaf biomass. These findings suggest plant size and age can be used as robust predictors of a plants vulnerability to browsing. An increase in tree cover requires successful transitions of seedlings to saplings (also known as release). The results of this study suggest that in semi-arid savannas, browsing can impact tree cover through imposing a release bottleneck for tree seedlings and to lesser extent saplings. By limiting tree growth plants are kept in a disturbance trap and will therefore be exposed to not only browsers but fire. These findings also have important implications for tree-grass coexistence dynamics, suggesting that specific size and browsing thresholds should be considered in savanna management.
- Full Text:
- Date Issued: 2017
- Authors: Perumal, Lavinia
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4899 , vital:20741
- Description: Savannas are characterised by a continuous grass layer with scattered trees at varying densities. This vegetation structure is determined by several interacting factors, including fire, herbivory, resource competition and atmospheric CO2 concentration. The preservation of savanna biomes is important and a shift towards a woody biome threatens savanna globally. Bush encroachment which describes the shift towards domination of savannas by C3 woody plants, is especially acute in southern Africa. In semi-arid rangelands, encroachment progresses to dense thickets dominated by thorny and unpalatable bushes and trees. There is evidence that bush encroachment is driven by a reduction in fire and browsing events as well as their interaction. Despite browsing having strong effects on African savannas its isolated role in maintaining tree-grass coexistence has not received as much attention as the role of fire. Therefore the overall aim of this study was to examine the effects of browsing on seedlings of a commonly encroaching species, Vachellia karroo. Browsing was hypothesized to be a demographic release bottleneck for bush encroachment in a semiarid (MAP ~550mm) savanna in the Eastern Cape of South Africa, where fire has been historically rare. In a single study I explored the fate of V. karroo seedlings (less than a year old) following browsing in sub canopy and inter canopy microhabitats. Additionally, I explored how the fate of a seedling changed under high and low tree cover. Firstly, I investigated the type, intensity and frequency of herbivory, from both small and large herbivores, which seedlings were subjected to. Results revealed that browsing was severe and frequent with the majority of seedlings browsed more than twice over a 12 month period. Large browsers such as kudu and impala caused high seedling mortality (46%) while smaller browsers such as invertebrates were more effective at suppressing growth. Microhabitat had little impact on seedling survival, but significantly influenced plant compensatory growth. Reduced seedling growth following browsing was observed in the sub-canopy in comparison to seedling growth in full sunlight in the intercanopy, suggesting V.karroo may be shade intolerant. Secondly, the effect of tree cover on browsed seedlings was determined by quantifying browsing frequency and intensity at high and low tree cover. No differences in browsing intensity and frequency were observed between high and low tree cover. However, high tree cover due to bush encroachment limited seedling above ground growth. The aim of the second study was to investigate how V.karroo survival and growth were influenced by its age and size following simulated browsing. I explored this aim through field and greenhouse experiments. I was particularly interested in testing how plant sensitivity to varying defoliation intensities of repeated browsing varied with plant age (known ages of 6, 12, 16 and 30 weeks). There were large differences in mortality between the different age groups. Furthermore, age interacted with repeated browsing and negatively influenced seedling survival and regrowth. Older seedlings (16 and 30 week old) had greater survival and higher browsing frequencies resulted in greater mortality and reduced growth. The threshold age after which seedlings become more tolerant to herbivory occurs at an age of 28 weeks. Seedlings less than six weeks old experiencing intense (100 % defoliation)browsing had a very low probability (33%) of survival following just a single defoliation. Interestingly, all 16 week old seedlings regrew most of their foliage following a moderate (50%) defoliation with some plants overcompensating for leaf loss. The field study revealed two distinct demographic stages based on age and size (seedlings< 9 mm and saplings >9 mm in stem basal diameter (SBD)). Browsing had a strong negative effect on seedlings, resulting in reduced investment in leaf biomass. These findings suggest plant size and age can be used as robust predictors of a plants vulnerability to browsing. An increase in tree cover requires successful transitions of seedlings to saplings (also known as release). The results of this study suggest that in semi-arid savannas, browsing can impact tree cover through imposing a release bottleneck for tree seedlings and to lesser extent saplings. By limiting tree growth plants are kept in a disturbance trap and will therefore be exposed to not only browsers but fire. These findings also have important implications for tree-grass coexistence dynamics, suggesting that specific size and browsing thresholds should be considered in savanna management.
- Full Text:
- Date Issued: 2017
A review of how teachers are using the renewable energy materials in their lessons
- Authors: Lambrechts, Therese
- Date: 2017
- Subjects: Renewable energy sources -- Study and teaching -- South Africa , Renewable energy sources -- Study and teaching -- South Africa -- South Africa , Curriculum evaluation -- South Africa , Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/13888 , vital:21864
- Description: Climate change and renewable energy have recently become part of the school curriculum in South Africa. Many teachers at the secondary school level thus have to teach topics with which they are not (necessarily) familiar. The Centre for Renewable and Sustainable Energy Studies at Stellenbosch University has established a schools' programme to provide materials to aid the educators in the teaching of renewable energy topics. A research-based set of Learning Teaching Support Material (LTSM) was developed for high school educators. The learning material includes a DVD, PowerPoint presentations, posters, a teacher's manual, and assignments that can be used in different subjects. This study reports and reviews how teachers are currently using the material. Teacher accounts of materials use and evidence of learning in students work were solicited using an appreciative inquiry review process. The data reflected the value being created through patterns of materials use. A Vygotskian based task sequencing framework of Anne Edwards was used to examine the patterns of use which support learning. The use of the task sequencing as an analytical lens allowed the review to probe how knowledge representation was the primary use by teachers. Here they introduced learners to key concepts and to broaden their knowledge on renewable energy. The activities served to scaffold a clear learning progression but the activities were not strongly enough orientated towards ESD as learner-led processes of enquiry and action. The outcomes of the study will be used to update and better align the materials with a need for teachers to strengthen important ESD outcomes in the current curriculum.
- Full Text:
- Date Issued: 2017
- Authors: Lambrechts, Therese
- Date: 2017
- Subjects: Renewable energy sources -- Study and teaching -- South Africa , Renewable energy sources -- Study and teaching -- South Africa -- South Africa , Curriculum evaluation -- South Africa , Environmental education -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/13888 , vital:21864
- Description: Climate change and renewable energy have recently become part of the school curriculum in South Africa. Many teachers at the secondary school level thus have to teach topics with which they are not (necessarily) familiar. The Centre for Renewable and Sustainable Energy Studies at Stellenbosch University has established a schools' programme to provide materials to aid the educators in the teaching of renewable energy topics. A research-based set of Learning Teaching Support Material (LTSM) was developed for high school educators. The learning material includes a DVD, PowerPoint presentations, posters, a teacher's manual, and assignments that can be used in different subjects. This study reports and reviews how teachers are currently using the material. Teacher accounts of materials use and evidence of learning in students work were solicited using an appreciative inquiry review process. The data reflected the value being created through patterns of materials use. A Vygotskian based task sequencing framework of Anne Edwards was used to examine the patterns of use which support learning. The use of the task sequencing as an analytical lens allowed the review to probe how knowledge representation was the primary use by teachers. Here they introduced learners to key concepts and to broaden their knowledge on renewable energy. The activities served to scaffold a clear learning progression but the activities were not strongly enough orientated towards ESD as learner-led processes of enquiry and action. The outcomes of the study will be used to update and better align the materials with a need for teachers to strengthen important ESD outcomes in the current curriculum.
- Full Text:
- Date Issued: 2017