A capabilities analysis: degree mobility and the impact of returning South African alumni on their home country’s sustainable development
- Authors: Mwatunga, Carine Brigitte
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436570 , vital:73283 , DOI 10.21504/10962/436570
- Description: The significance of sustainable development (SD) has gained increasing attention, particularly since introducing the Sustainable Development Goals (SDGs) in 2015. SDG 4 focuses on ensuring inclusive and high-quality education for all individuals, as well as the provision of equitable access to lifelong learning opportunities. In addition, SDG 4 recognises education as a fundamental element of societal progress and SD. Given the role of education in fostering economic growth, social cohesion, and individual empowerment, SDG 4 is a crucial component of global efforts to foster a more prosperous and equitable world. The primary focus of the study explained in this thesis was to address a specific aspect of Higher Education (HE) within the framework of the SDGs. While SDG 4 covers a wide range of targets, such as expanding scholarship opportunities for individuals from the Global South to study abroad, there remains a lack of comprehensive understanding of how pursuing a degree in a foreign country can influence graduates' potential contributions to sustainable development (SD) upon returning to their home countries. Moreover, despite researchers highlighting the need for attention to this topic, it has not received adequate focus thus far. Therefore, drawing upon the framework of the capability approach (CA) to sustainable development, the study explored whether returning graduates could contribute to SD in South Africa. To integrate the concepts of SD and CA, the study developed a framework for a responsible agent (RA), which was facilitated through previous studies. This framework provides a set of capabilities that are essential for supporting SD in South Africa. Based on this framework, the study comprehensively explored the experiences of postgraduate students and their potential to contribute to SD in South Africa. The study drew on survey data, semi structured interview, and document analysis to gain insights into how the structures of six selected scholarships aligned with SD objectives. However, upon analysing the eligibility criteria of these scholarships, it became evident that they already take into account certain capabilities associated with the RA in candidates. Furthermore, the analysis revealed that these scholarships tend to favour candidates who exhibit the potential to succeed in their professional endeavours. Therefore, this selection bias may exacerbate the existing inequalities within the South African education system. By disproportionately supporting candidates with advantages or resources, the scholarships may inadvertently perpetuate the disparities in educational opportunities and hinder progress toward a more equitable system. After administering questionnaires to alumni who had received these six scholarships, they were asked to voluntary participate in semi-structured interviews. Thereafter, data obtained was combined with document analysis, questionnaires, and interviews were analysed drawing on the RA framework with a narrative inquiry approach. The analysis of the data gathered during interviews with alumni revealed that certain capabilities were demonstrated and developed because of their degree mobility (pursuing degrees in different locations). However, it was also observed that some capabilities were negatively impacted by this mobility. Thus, the findings suggested a nuanced relationship between degree mobility and the development of specific capabilities amongst alumni, warranting further investigation to understand the implications of degree mobility on various capabilities. The investigation of the study revealed that the structure of the selected scholarships is not fully aligned with SD and that some capabilities can be damaged through degree mobility. To ensure that the scholarships truly support SD, they would require restructuring and (1) lowering expectations and preparing alumni for an often rather difficult return to South Africa; (2) limiting the available scholarships to degree programmes that are less or not affordable at all in South Africa; (3) implementing a re-entry strategy for returning alumni to make the return more manageable; and (4) collecting more data to create a deeper understanding about the possible achievements of individual alumni. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Mwatunga, Carine Brigitte
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436570 , vital:73283 , DOI 10.21504/10962/436570
- Description: The significance of sustainable development (SD) has gained increasing attention, particularly since introducing the Sustainable Development Goals (SDGs) in 2015. SDG 4 focuses on ensuring inclusive and high-quality education for all individuals, as well as the provision of equitable access to lifelong learning opportunities. In addition, SDG 4 recognises education as a fundamental element of societal progress and SD. Given the role of education in fostering economic growth, social cohesion, and individual empowerment, SDG 4 is a crucial component of global efforts to foster a more prosperous and equitable world. The primary focus of the study explained in this thesis was to address a specific aspect of Higher Education (HE) within the framework of the SDGs. While SDG 4 covers a wide range of targets, such as expanding scholarship opportunities for individuals from the Global South to study abroad, there remains a lack of comprehensive understanding of how pursuing a degree in a foreign country can influence graduates' potential contributions to sustainable development (SD) upon returning to their home countries. Moreover, despite researchers highlighting the need for attention to this topic, it has not received adequate focus thus far. Therefore, drawing upon the framework of the capability approach (CA) to sustainable development, the study explored whether returning graduates could contribute to SD in South Africa. To integrate the concepts of SD and CA, the study developed a framework for a responsible agent (RA), which was facilitated through previous studies. This framework provides a set of capabilities that are essential for supporting SD in South Africa. Based on this framework, the study comprehensively explored the experiences of postgraduate students and their potential to contribute to SD in South Africa. The study drew on survey data, semi structured interview, and document analysis to gain insights into how the structures of six selected scholarships aligned with SD objectives. However, upon analysing the eligibility criteria of these scholarships, it became evident that they already take into account certain capabilities associated with the RA in candidates. Furthermore, the analysis revealed that these scholarships tend to favour candidates who exhibit the potential to succeed in their professional endeavours. Therefore, this selection bias may exacerbate the existing inequalities within the South African education system. By disproportionately supporting candidates with advantages or resources, the scholarships may inadvertently perpetuate the disparities in educational opportunities and hinder progress toward a more equitable system. After administering questionnaires to alumni who had received these six scholarships, they were asked to voluntary participate in semi-structured interviews. Thereafter, data obtained was combined with document analysis, questionnaires, and interviews were analysed drawing on the RA framework with a narrative inquiry approach. The analysis of the data gathered during interviews with alumni revealed that certain capabilities were demonstrated and developed because of their degree mobility (pursuing degrees in different locations). However, it was also observed that some capabilities were negatively impacted by this mobility. Thus, the findings suggested a nuanced relationship between degree mobility and the development of specific capabilities amongst alumni, warranting further investigation to understand the implications of degree mobility on various capabilities. The investigation of the study revealed that the structure of the selected scholarships is not fully aligned with SD and that some capabilities can be damaged through degree mobility. To ensure that the scholarships truly support SD, they would require restructuring and (1) lowering expectations and preparing alumni for an often rather difficult return to South Africa; (2) limiting the available scholarships to degree programmes that are less or not affordable at all in South Africa; (3) implementing a re-entry strategy for returning alumni to make the return more manageable; and (4) collecting more data to create a deeper understanding about the possible achievements of individual alumni. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
- Full Text:
- Date Issued: 2024-04-05
A multidisciplinary study to assess the ecology of the Cape sea urchin, Parechinus angulosus, and its emerging use as a bioindicator to monitor coastal resiliency
- Authors: Redelinghuys, Suzanne
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435691 , vital:73179 , DOI 10.21504/10962/435692
- Description: The resilience of marine species in the face of unpredictable climate change stands as a paramount concern for the maintenance of ecological stability. Under such fluctuating conditions, it is critical to understand how organisms mitigate these effects in physiological, genetic, and morphological terms. To that end, this thesis focused on the Cape sea urchin, Parechinus angulosus, employing a multidisciplinary approach encompassing morphology, genomics, and gut microbial diversity to assess its potential as a bioindicator species and elucidate its adaptive strategies in response to varying environmental conditions along the South African coastline. This was achieved through studying their anatomy in order to link observed variation to prevailing local environmental conditions, aided by the species’ wide distribution range which allows insight into adaptations across broad geographic regions and ecological settings. The first empirical chapter, Chapter 3, focusing on eight key morphometric traits of test, Aristotle’s lantern and spines, revealed distinct variation in the Cape sea urchin's morphology between the east and west coasts of South Africa, suggesting the presence of some level of local adaptation to the prevailing environmental factors found on the east and west coasts of South Africa. This points to potential bioindicator capabilities of the species, reflecting adaptive divergence amidst contrasting environmental conditions. Further analysis is however necessary in order to isolate specific physiological trends that may be associated with these morphometric differences, thereby enhancing and tightening their ecological implications. The second experimental chapter, Chapter 4, delved into the genetic structure of the Cape urchin by investigating genome-wide diversity, the presence of cryptic population structure, and spatial patterns of genomic diversity. Moderate genomic differentiation was detected among populations along the eastern and western coasts of South Africa by outlier loci that may undergo natural selection, which could indicate local adaptation to environmental conditions. This pattern hints at adaptive differentiation and cryptic genetic structures within the Cape sea urchin populations and emphasises the species' potential adaptive responses to localised (in this case regional) environmental pressures. Assigning functional significance to these genetic variations will require a comprehensive annotated reference genome, a limitation acknowledged in the current study. Chapter 5 explored the gut microbial diversity and revealed significant compositional variations between the east and west coast populations of South Africa, confirming regional and inter-regional variation. This chapter also highlighted the essential biochemical pathways critical to the survival of the host which is crucial for assessing the health of the urchin host. Together, the functional content of the gut bacteria and microbial diversity showcases its potential as a bioindicator for coastal ecosystem health. Logistical challenges and confounding factors like host physiology will need to be fully considered for its effective application. Overall, the findings of this doctoral research suggest that the Cape sea urchin displays promising characteristics as a bioindicator species due to its morphological, genetic, and gut microbial variations in response to environmental differences, providing a diverse array of means in which urchins could be used as bioindicators, from their uses to assess water quality and detect pollution, to ecosystem health monitoring and biodiversity studies in which sea urchin abundance, distribution, and presence are monitored. Further research, integrating these multidisciplinary approaches is recommended to validate and refine its bioindicator potential. Additionally, the development of a comprehensive annotated reference genome is imperative to harness the species' genetic information effectively. This study underscores the significance of integrating multiple disciplines in understanding how species respond to environmental change and their potentials contributions to monitor ecological resilience. The original multidisciplinary approach, combined with high computational outputs presents a promising framework for a comprehensive ecological monitoring in marine ecosystems. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Redelinghuys, Suzanne
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435691 , vital:73179 , DOI 10.21504/10962/435692
- Description: The resilience of marine species in the face of unpredictable climate change stands as a paramount concern for the maintenance of ecological stability. Under such fluctuating conditions, it is critical to understand how organisms mitigate these effects in physiological, genetic, and morphological terms. To that end, this thesis focused on the Cape sea urchin, Parechinus angulosus, employing a multidisciplinary approach encompassing morphology, genomics, and gut microbial diversity to assess its potential as a bioindicator species and elucidate its adaptive strategies in response to varying environmental conditions along the South African coastline. This was achieved through studying their anatomy in order to link observed variation to prevailing local environmental conditions, aided by the species’ wide distribution range which allows insight into adaptations across broad geographic regions and ecological settings. The first empirical chapter, Chapter 3, focusing on eight key morphometric traits of test, Aristotle’s lantern and spines, revealed distinct variation in the Cape sea urchin's morphology between the east and west coasts of South Africa, suggesting the presence of some level of local adaptation to the prevailing environmental factors found on the east and west coasts of South Africa. This points to potential bioindicator capabilities of the species, reflecting adaptive divergence amidst contrasting environmental conditions. Further analysis is however necessary in order to isolate specific physiological trends that may be associated with these morphometric differences, thereby enhancing and tightening their ecological implications. The second experimental chapter, Chapter 4, delved into the genetic structure of the Cape urchin by investigating genome-wide diversity, the presence of cryptic population structure, and spatial patterns of genomic diversity. Moderate genomic differentiation was detected among populations along the eastern and western coasts of South Africa by outlier loci that may undergo natural selection, which could indicate local adaptation to environmental conditions. This pattern hints at adaptive differentiation and cryptic genetic structures within the Cape sea urchin populations and emphasises the species' potential adaptive responses to localised (in this case regional) environmental pressures. Assigning functional significance to these genetic variations will require a comprehensive annotated reference genome, a limitation acknowledged in the current study. Chapter 5 explored the gut microbial diversity and revealed significant compositional variations between the east and west coast populations of South Africa, confirming regional and inter-regional variation. This chapter also highlighted the essential biochemical pathways critical to the survival of the host which is crucial for assessing the health of the urchin host. Together, the functional content of the gut bacteria and microbial diversity showcases its potential as a bioindicator for coastal ecosystem health. Logistical challenges and confounding factors like host physiology will need to be fully considered for its effective application. Overall, the findings of this doctoral research suggest that the Cape sea urchin displays promising characteristics as a bioindicator species due to its morphological, genetic, and gut microbial variations in response to environmental differences, providing a diverse array of means in which urchins could be used as bioindicators, from their uses to assess water quality and detect pollution, to ecosystem health monitoring and biodiversity studies in which sea urchin abundance, distribution, and presence are monitored. Further research, integrating these multidisciplinary approaches is recommended to validate and refine its bioindicator potential. Additionally, the development of a comprehensive annotated reference genome is imperative to harness the species' genetic information effectively. This study underscores the significance of integrating multiple disciplines in understanding how species respond to environmental change and their potentials contributions to monitor ecological resilience. The original multidisciplinary approach, combined with high computational outputs presents a promising framework for a comprehensive ecological monitoring in marine ecosystems. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
Augmentation of Aphytis melinus DeBach (Hymenoptera: Aphelinidae) for the control of California red scale Aonidiella aurantii Maskell (Hemiptera: Diaspididae) on citrus
- De Beer, Ernst Friedrich Ludwig
- Authors: De Beer, Ernst Friedrich Ludwig
- Date: 2024-04-05
- Subjects: Aphytis melinus , Aphytis , Aonidiella aurantii , Citrus Diseases and pests South Africa , Pests Biological control
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435638 , vital:73175 , DOI 10.21504/10962/435638
- Description: Aphytis lingnanensis was reared and tested in South Africa in the early 2000s for augmentation against red scale on citrus and was found to be ineffective. Aphytis melinus is now commercially available and it is important that the efficacy of augmentation thereof on red scale is determined locally. Field trials, fitness assessments and molecular identification on A. melinus from two insectaries were done. Field trials was done in seven, five and six pairs of comparable release and control orchards across the Eastern and Western Cape during the seasons of 2019/2020, 2020/2021 and 2021/2022 respectively. Red scale infestation was monitored and a sample of 20 infested fruit from each orchard was randomly collected every four weeks. Aphytis spp. responsible for parasitism were identified and the percentage parasitism recorded. Results of this study of field trials suggest that the augmentation of A. melinus did not significantly increase the level of parasitism above that of the untreated control. Five repetitions with six replicates of flight and longevity tests were performed with wasps from each insectary. Wasps in the longevity test from two insectaries were kept at 23 °C and 65% RH with honey. Flight tests were performed in tubes of 16 by 30 cm, with a light above a clear, sticky ceiling at 23 °C and 65% RH. On average in five replicates, 65%, 33% and 17% A. melinus wasps were alive on day one, five and 10 respectively. The overall sex ratio was 1.58 for females to males, but 1.05, 2.19 and 2.66 for non-flyers, non-crawlers, crawlers, and flyers respectively. In flight tests for both insectaries combined, only 36.97% of wasps could initiate flight in 24 h while 56.96% remained on the tube floor, and 6.05% attempted to crawl upwards. No significant differences in flight performance were recorded between the two insectaries. Wasps from the local insectary lived significantly longer during the longevity tests but were shorter in transit than wasps from the overseas insectary. COI genes were sequenced and compared against Genbank sequences using BLAST. Molecular identifications did not confirm morphological identifications for all species, indicating unexpected genetic complexity. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: De Beer, Ernst Friedrich Ludwig
- Date: 2024-04-05
- Subjects: Aphytis melinus , Aphytis , Aonidiella aurantii , Citrus Diseases and pests South Africa , Pests Biological control
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435638 , vital:73175 , DOI 10.21504/10962/435638
- Description: Aphytis lingnanensis was reared and tested in South Africa in the early 2000s for augmentation against red scale on citrus and was found to be ineffective. Aphytis melinus is now commercially available and it is important that the efficacy of augmentation thereof on red scale is determined locally. Field trials, fitness assessments and molecular identification on A. melinus from two insectaries were done. Field trials was done in seven, five and six pairs of comparable release and control orchards across the Eastern and Western Cape during the seasons of 2019/2020, 2020/2021 and 2021/2022 respectively. Red scale infestation was monitored and a sample of 20 infested fruit from each orchard was randomly collected every four weeks. Aphytis spp. responsible for parasitism were identified and the percentage parasitism recorded. Results of this study of field trials suggest that the augmentation of A. melinus did not significantly increase the level of parasitism above that of the untreated control. Five repetitions with six replicates of flight and longevity tests were performed with wasps from each insectary. Wasps in the longevity test from two insectaries were kept at 23 °C and 65% RH with honey. Flight tests were performed in tubes of 16 by 30 cm, with a light above a clear, sticky ceiling at 23 °C and 65% RH. On average in five replicates, 65%, 33% and 17% A. melinus wasps were alive on day one, five and 10 respectively. The overall sex ratio was 1.58 for females to males, but 1.05, 2.19 and 2.66 for non-flyers, non-crawlers, crawlers, and flyers respectively. In flight tests for both insectaries combined, only 36.97% of wasps could initiate flight in 24 h while 56.96% remained on the tube floor, and 6.05% attempted to crawl upwards. No significant differences in flight performance were recorded between the two insectaries. Wasps from the local insectary lived significantly longer during the longevity tests but were shorter in transit than wasps from the overseas insectary. COI genes were sequenced and compared against Genbank sequences using BLAST. Molecular identifications did not confirm morphological identifications for all species, indicating unexpected genetic complexity. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
Co-occurrence of Sympatric Poroderma Species
- Authors: Watson, Ralph Gareth Andrew
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436649 , vital:73289 , DOI 10.21504/10962/436649
- Description: Species exploiting similar ecological niches are expected to adapt their behaviour, which can either promote or hinder coexistence. This study examined the ecological (dis)similarity between the endemic Poroderma africanum (pyjama catshark) and Poroderma pantherinum (leopard catshark) in Mossel Bay, South Africa. The co-occurrence of these species was examined along the ecological axes of time, trophic position and space, between October 2015 and April 2018, through the use of Baited Remote Underwater Videos (BRUV), gastric lavage, and acoustic telemetry. Through the deployment of 197 BRUVs, P. africanum showed a seasonal, higher Relative Abundance (RA = 0.52), occurring more frequently during winter months, while showing an overall decline in RA over the course of the study period. Poroderma pantherinum on the other hand, showed a lower, unseasonal RA (0.20), remaining relatively stable throughout the study period. The BRUV deployments indicated that the two species showed a positive co-occurrence with one other, being sighted in BRUV deployments more frequently together as opposed to in isolation/at random. Acoustic telemetry indicated that the two species were active during different diel periods, influenced by a complex combination of tidal and diel rhythms, while P. pantherinum showed a higher residency compared to P. africanum (P. pantherinum: Continuous Residency Time (CRT)24 = 3.32 days (mean), 95% CI: 2.53–4.11 days; P. africanum: CRT24 = 2.01 days, 95% CI: 1.66–2.36 days). While the two species are sympatric in nature, and have an overlapping, endemic, distribution, acoustic telemetry indicated that 1 ABSTRACT P. africanum showed higher degrees of movement throughout the acoustic receiver array (P. africanum: edge density (ED) = 0.25; P. pantherinum: ED = 0.12); however, certain areas of the bay showed to be of high importance for both species. Both species revealed high levels of intra- and inter-specific variation in both residency and movement behaviour. Gastric lavage indicated partially overlapping trophic niches, between the two Poroderma spp. Poroderma africanum had a generalist diet, dominated by teleosts (Index of Relative Importance (IRI)% = 22.69), octopus (IRI% = 11.48) and discarded bait (IRI% = 64.54), while P. pantherinum showed indications of being a specialist predator, with a diet dominated by cephalopods (IRI% = 83.68). The two Poroderma spp. showed a partially overlapping, but separate trophic niches, while displaying spatial dissimilarity in diet. The study suggests that the two species are able to coexist within the same geographical area through niche differentiation across trophic and temporal ecological axes, with varying spatial use. The intra- and inter-specific differences between the two species may complicate elasmobranch management efforts for these co-occurring endemic catsharks, and as such, efforts should follow either an individual species approach, which is often not feasible, or an ecosystem-based approach, as opposed to considering the genus as a whole. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Watson, Ralph Gareth Andrew
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436649 , vital:73289 , DOI 10.21504/10962/436649
- Description: Species exploiting similar ecological niches are expected to adapt their behaviour, which can either promote or hinder coexistence. This study examined the ecological (dis)similarity between the endemic Poroderma africanum (pyjama catshark) and Poroderma pantherinum (leopard catshark) in Mossel Bay, South Africa. The co-occurrence of these species was examined along the ecological axes of time, trophic position and space, between October 2015 and April 2018, through the use of Baited Remote Underwater Videos (BRUV), gastric lavage, and acoustic telemetry. Through the deployment of 197 BRUVs, P. africanum showed a seasonal, higher Relative Abundance (RA = 0.52), occurring more frequently during winter months, while showing an overall decline in RA over the course of the study period. Poroderma pantherinum on the other hand, showed a lower, unseasonal RA (0.20), remaining relatively stable throughout the study period. The BRUV deployments indicated that the two species showed a positive co-occurrence with one other, being sighted in BRUV deployments more frequently together as opposed to in isolation/at random. Acoustic telemetry indicated that the two species were active during different diel periods, influenced by a complex combination of tidal and diel rhythms, while P. pantherinum showed a higher residency compared to P. africanum (P. pantherinum: Continuous Residency Time (CRT)24 = 3.32 days (mean), 95% CI: 2.53–4.11 days; P. africanum: CRT24 = 2.01 days, 95% CI: 1.66–2.36 days). While the two species are sympatric in nature, and have an overlapping, endemic, distribution, acoustic telemetry indicated that 1 ABSTRACT P. africanum showed higher degrees of movement throughout the acoustic receiver array (P. africanum: edge density (ED) = 0.25; P. pantherinum: ED = 0.12); however, certain areas of the bay showed to be of high importance for both species. Both species revealed high levels of intra- and inter-specific variation in both residency and movement behaviour. Gastric lavage indicated partially overlapping trophic niches, between the two Poroderma spp. Poroderma africanum had a generalist diet, dominated by teleosts (Index of Relative Importance (IRI)% = 22.69), octopus (IRI% = 11.48) and discarded bait (IRI% = 64.54), while P. pantherinum showed indications of being a specialist predator, with a diet dominated by cephalopods (IRI% = 83.68). The two Poroderma spp. showed a partially overlapping, but separate trophic niches, while displaying spatial dissimilarity in diet. The study suggests that the two species are able to coexist within the same geographical area through niche differentiation across trophic and temporal ecological axes, with varying spatial use. The intra- and inter-specific differences between the two species may complicate elasmobranch management efforts for these co-occurring endemic catsharks, and as such, efforts should follow either an individual species approach, which is often not feasible, or an ecosystem-based approach, as opposed to considering the genus as a whole. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-05
Ecological impacts of photoautotrophic Euendoliths on South African mussel beds
- Dievart, Alexia Madeleine Angèle
- Authors: Dievart, Alexia Madeleine Angèle
- Date: 2024-04-05
- Subjects: Mexilhao mussel , Polychaeta , Epibiosis , Infauna , Infrared thermography , Thermography , Common garden experiment
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435650 , vital:73176 , DOI 10.21504/10962/435650
- Description: Aphytis lingnanensis was reared and tested in South Africa in the early 2000s for augmentation against red scale on citrus and was found to be ineffective. Aphytis melinus is now commercially available and it is important that the efficacy of augmentation thereof on red scale is determined locally. Field trials, fitness assessments and molecular identification on A. melinus from two insectaries were done. Field trials was done in seven, five and six pairs of comparable release and control orchards across the Eastern and Western Cape during the seasons of 2019/2020, 2020/2021 and 2021/2022 respectively. Red scale infestation was monitored and a sample of 20 infested fruit from each orchard was randomly collected every four weeks. Aphytis spp. responsible for parasitism were identified and the percentage parasitism recorded. Results of this study of field trials suggest that the augmentation of A. melinus did not significantly increase the level of parasitism above that of the untreated control. Five repetitions with six replicates of flight and longevity tests were performed with wasps from each insectary. Wasps in the longevity test from two insectaries were kept at 23 °C and 65% RH with honey. Flight tests were performed in tubes of 16 by 30 cm, with a light above a clear, sticky ceiling at 23 °C and 65% RH. On average in five replicates, 65%, 33% and 17% A. melinus wasps were alive on day one, five and 10 respectively. The overall sex ratio was 1.58 for females to males, but 1.05, 2.19 and 2.66 for non-flyers, non-crawlers, crawlers, and flyers respectively. In flight tests for both insectaries combined, only 36.97% of wasps could initiate flight in 24 h while 56.96% remained on the tube floor, and 6.05% attempted to crawl upwards. No significant differences in flight performance were recorded between the two insectaries. Wasps from the local insectary lived significantly longer during the longevity tests but were shorter in transit than wasps from the overseas insectary. COI genes were sequenced and compared against Genbank sequences using BLAST. Molecular identifications did not confirm morphological identifications for all species, indicating unexpected genetic complexity. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Dievart, Alexia Madeleine Angèle
- Date: 2024-04-05
- Subjects: Mexilhao mussel , Polychaeta , Epibiosis , Infauna , Infrared thermography , Thermography , Common garden experiment
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435650 , vital:73176 , DOI 10.21504/10962/435650
- Description: Aphytis lingnanensis was reared and tested in South Africa in the early 2000s for augmentation against red scale on citrus and was found to be ineffective. Aphytis melinus is now commercially available and it is important that the efficacy of augmentation thereof on red scale is determined locally. Field trials, fitness assessments and molecular identification on A. melinus from two insectaries were done. Field trials was done in seven, five and six pairs of comparable release and control orchards across the Eastern and Western Cape during the seasons of 2019/2020, 2020/2021 and 2021/2022 respectively. Red scale infestation was monitored and a sample of 20 infested fruit from each orchard was randomly collected every four weeks. Aphytis spp. responsible for parasitism were identified and the percentage parasitism recorded. Results of this study of field trials suggest that the augmentation of A. melinus did not significantly increase the level of parasitism above that of the untreated control. Five repetitions with six replicates of flight and longevity tests were performed with wasps from each insectary. Wasps in the longevity test from two insectaries were kept at 23 °C and 65% RH with honey. Flight tests were performed in tubes of 16 by 30 cm, with a light above a clear, sticky ceiling at 23 °C and 65% RH. On average in five replicates, 65%, 33% and 17% A. melinus wasps were alive on day one, five and 10 respectively. The overall sex ratio was 1.58 for females to males, but 1.05, 2.19 and 2.66 for non-flyers, non-crawlers, crawlers, and flyers respectively. In flight tests for both insectaries combined, only 36.97% of wasps could initiate flight in 24 h while 56.96% remained on the tube floor, and 6.05% attempted to crawl upwards. No significant differences in flight performance were recorded between the two insectaries. Wasps from the local insectary lived significantly longer during the longevity tests but were shorter in transit than wasps from the overseas insectary. COI genes were sequenced and compared against Genbank sequences using BLAST. Molecular identifications did not confirm morphological identifications for all species, indicating unexpected genetic complexity. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
Exploring and expanding teachers’ gender and culturally responsive practices when mediating learning of chemistry in rural schools in Namibia
- Authors: Haimene, Johanna Shetulimba
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436535 , vital:73280 , DOI 10.21504/10962/436536
- Description: Gender and cultural dimensions are critical aspects of the education system. Schools are full of gender and cultural stereotypes when it comes to the teaching and learning of science. This calls for the teachers to be gender and culturally responsive in their science classrooms. This is also to ensure that the educational needs of both boys and girls are addressed. The Namibian National Curriculum for Basic Education advocates the application of gender equity at all levels and in every aspect of the curriculum and teachers are central to the implementation of this curriculum. However, while the policy has been formulated at the macro level of the education system, little if any research has been done in Namibia on exploring how teachers are coping with and implementing the curriculum based on gender and cultural aspects. This includes how teachers are responding to gender issues and how they eradicate bias and discrimination to ensure equality and equity for both boys and girls in their science teaching. Against this backdrop, this study aimed to explore and expand Grade 9 Physical Science teachers’ gender and culturally responsive practices in science classrooms when mediating learning of chemistry topics using acids and bases and combustion reactions as examples. The study focused on working with teachers with the purpose of improving their practices through collaborative partnerships and enriching all the participants (teachers and researcher) as they were seen as co-learners and co-researchers. Hence, this study was underpinned by interpretivist and critical paradigms. It adopted a case study research design. Six Grade 9 Physical Science teachers from the Oshikoto Region were the participants in this study. Qualitative data were generated using questionnaires, interviews (semi-structured and stimulated recall), classroom observations and Change Laboratory Workshops (CLWs) in which we co-developed a tool to address gender and cultural responsiveness. Vygotsky’s socio-cultural theory and Engeström’s cultural-historical activity theory (CHAT) were used as theoretical frameworks to surface contradictions or tensions that exist in the teaching and learning process. A thematic approach to data analysis was employed to come up with sub-themes and themes. The findings of the study revealed that the teachers seemed to have an understanding of being gender and culturally responsive when they are mediating their lessons. However, some contradictions constrained them from being gender and culturally responsive. The surfaced contradictions included the lack of examples that are not gender and culturally biased, poor participation of the learners during lesson presentation and low confidence among the learners and language barriers. In addition, the findings revealed that teachers need professional development in interpreting policies and the curriculum and techniques for analysing gender and cultural issues pertaining to the teaching and learning process. Through CLWs, we co-developed a mediational tool that could guide teachers on how to be gender and culturally responsive. The findings also revealed that participation of teachers in the CLWs equipped them with resources on how to be gender and culturally responsive in their classrooms. The study recommends that teachers need to be involved in continuing professional development to support them with the correct interpretation and enactment of the curriculum and other policies. The policy developers need to be in contact with the policy implementers to evaluate the implementation of these policies and provide guidance where necessary. Moreover, teachers need to form professional learning communities in order to share their best practices and transform them. This might assist them in addressing gender and cultural issues that are encountered in the teaching and learning process. , Thesis (PhD) -- Faculty of Education, Secondary and Post School Education, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Haimene, Johanna Shetulimba
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436535 , vital:73280 , DOI 10.21504/10962/436536
- Description: Gender and cultural dimensions are critical aspects of the education system. Schools are full of gender and cultural stereotypes when it comes to the teaching and learning of science. This calls for the teachers to be gender and culturally responsive in their science classrooms. This is also to ensure that the educational needs of both boys and girls are addressed. The Namibian National Curriculum for Basic Education advocates the application of gender equity at all levels and in every aspect of the curriculum and teachers are central to the implementation of this curriculum. However, while the policy has been formulated at the macro level of the education system, little if any research has been done in Namibia on exploring how teachers are coping with and implementing the curriculum based on gender and cultural aspects. This includes how teachers are responding to gender issues and how they eradicate bias and discrimination to ensure equality and equity for both boys and girls in their science teaching. Against this backdrop, this study aimed to explore and expand Grade 9 Physical Science teachers’ gender and culturally responsive practices in science classrooms when mediating learning of chemistry topics using acids and bases and combustion reactions as examples. The study focused on working with teachers with the purpose of improving their practices through collaborative partnerships and enriching all the participants (teachers and researcher) as they were seen as co-learners and co-researchers. Hence, this study was underpinned by interpretivist and critical paradigms. It adopted a case study research design. Six Grade 9 Physical Science teachers from the Oshikoto Region were the participants in this study. Qualitative data were generated using questionnaires, interviews (semi-structured and stimulated recall), classroom observations and Change Laboratory Workshops (CLWs) in which we co-developed a tool to address gender and cultural responsiveness. Vygotsky’s socio-cultural theory and Engeström’s cultural-historical activity theory (CHAT) were used as theoretical frameworks to surface contradictions or tensions that exist in the teaching and learning process. A thematic approach to data analysis was employed to come up with sub-themes and themes. The findings of the study revealed that the teachers seemed to have an understanding of being gender and culturally responsive when they are mediating their lessons. However, some contradictions constrained them from being gender and culturally responsive. The surfaced contradictions included the lack of examples that are not gender and culturally biased, poor participation of the learners during lesson presentation and low confidence among the learners and language barriers. In addition, the findings revealed that teachers need professional development in interpreting policies and the curriculum and techniques for analysing gender and cultural issues pertaining to the teaching and learning process. Through CLWs, we co-developed a mediational tool that could guide teachers on how to be gender and culturally responsive. The findings also revealed that participation of teachers in the CLWs equipped them with resources on how to be gender and culturally responsive in their classrooms. The study recommends that teachers need to be involved in continuing professional development to support them with the correct interpretation and enactment of the curriculum and other policies. The policy developers need to be in contact with the policy implementers to evaluate the implementation of these policies and provide guidance where necessary. Moreover, teachers need to form professional learning communities in order to share their best practices and transform them. This might assist them in addressing gender and cultural issues that are encountered in the teaching and learning process. , Thesis (PhD) -- Faculty of Education, Secondary and Post School Education, 2024
- Full Text:
- Date Issued: 2024-04-05
Investigating occupation as frame for planning and developing agricultural extension VET skills for climate resilience: cross-case analysis of Alice, South Africa, and Gulu, Uganda
- Authors: Muhangi, Sidney
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436559 , vital:73282 , DOI 10.21504/10962/436559
- Description: In sub-Saharan Africa and most of the Global South, climate change is challenging work and livelihoods for smallholder farmers who depend on rainfed farming, demanding climate resilience. Smallholder agriculture in Africa remains a mainstay for most economies and livelihoods, including South Africa and Uganda. My firsthand experience in Uganda as a subsistence farmer revealed the vitality of extension services to farmers. Participating in VETAfrica 4.0, a VET skill planning project, sparked my interest in examining the adequacy of 'Occupation' as a skills planning tool for addressing contemporary climate change challenges faced by extension officers and farmers, with implications for skills development. This research sought to answer the question: What is the theoretical and practical history and current constitution of the agricultural extension officer occupation as a mediating unit of intervention for VET skills planning, and is it adequate for climate resilience? The study addressed five objectives. First, the study undertook a historical review of occupation as a mediating unit of intervention for skills planning. Secondly, the study examined current descriptions of the extension occupation as used for skills planning in Africa. Thirdly, in order to better understand the operationalisation of this skills planning instrument, the study examined aspects of skills development, specifically how VET preparation for extension work was taking place in response to the need for climate resilience through a curriculum review and the experiences and related work activities of extension services actors. The study also reviewed agricultural extension and VET policy, and labour market data for its responsiveness to climate resilience. In response to the findings of Objectives 1-4, a fifth objective was developed to offer expanded possibilities for a mediating unit of intervention for skills planning and development relevant to climate resilience in agricultural extension, as this appeared to be needed. To develop the study, I drew on the Social Ecosystems Model (SEM) for skills, which raises the issue of mediation in skills development. I also drew on Cultural-Historical Activity Theory (CHAT) to help theorise the mediation in the SEM for skills, where different activity systems (policy, training and extension, farming) were present. This framework allowed me to probe how these activity systems were mediating climate-resilient skills development with/for extension services (or not). Empirical data was produced through secondary and primary data, generated in two case study contexts using a cross-case design. Documentary analysis involved analysing policy documents, study curricula and historical literature to develop an understanding of historical sociology of occupation as a skills planning mediating unit and insight into contemporary understanding of how occupational frameworks are structured and deployed. Analysis was undertaken in two stages; firstly, through in-depth cases of occupation as mediating unit of intervention for skills planning, and aspects of skills development as influenced by this as influenced by this mediating unit (Chapter 5 and 6). This offered a first layer of analysis and insights into temporality, verticalities, mediation and horizontalities in the SEM for skills in each case. Secondly, abduction was undertaken to build models of the SEM for skills as found in each of the two countries using the SEM and CHAT analytical tools (Chapter 7), showing the need for skills planning tools that are more closely related to and relevant to the contexts of skills development. Findings revealed insights into the SEM for skills related to ecological time, notably a mismatch between the cultural-historical time of occupational skills planning and development, and the temporal demands for climate resilience. Historical analysis the deep rootedness of occupations and occupational structures in colonial histories and traditions, going back as far as the medieval era, with current occupations still bearing features of ancient occupational guild practices and hence not adequately responsive to climate change, affecting the SEM for skills in both cases and producing contradictions. Analysis further revealed that contemporary agricultural extension in Africa is decentralised and pluralistic, with few extension-related policies employed underdeveloped. Labour market in both South Africa and Uganda are not adequately orientated to climate resilience and fail to include climate resilience expertise, despite a need for this amongst farmers and by policy, revealing contradictions between various policy activity systems, which are not adequately facilitating. Empirical findings from study sites revealed that VET preparation for extension work lacks responsiveness to climate resilience within the skills ecosystem. Consequently, extension officers lack expertise in climate resilience, which is an increasing demand expressed by farmers and other horizontal activity systems in the SEM for skills. Through a more complex understanding of the extension officer occupation and its development in skills ecosystem in Africa, the study proposes a broader mediating unit of intervention for skills planning than that of ‘occupation’ only. The mediating unit of intervention put forward for skills planning is a workstream mapping approach for climate resilient extension training in VET. This planning approach has implications for skills development viewed as work, learning and living involving more than one activity system in the skills development landscape, thus also broadening the approach to VET. The study concludes with recommendations to further test this approach. Finally, it makes recommendations that can inform: 1) curriculum innovation, 2) extension practice, 3) policy, and 4) research. , Thesis (PhD) -- Faculty of Education, Secondary and Post School Education, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Muhangi, Sidney
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/436559 , vital:73282 , DOI 10.21504/10962/436559
- Description: In sub-Saharan Africa and most of the Global South, climate change is challenging work and livelihoods for smallholder farmers who depend on rainfed farming, demanding climate resilience. Smallholder agriculture in Africa remains a mainstay for most economies and livelihoods, including South Africa and Uganda. My firsthand experience in Uganda as a subsistence farmer revealed the vitality of extension services to farmers. Participating in VETAfrica 4.0, a VET skill planning project, sparked my interest in examining the adequacy of 'Occupation' as a skills planning tool for addressing contemporary climate change challenges faced by extension officers and farmers, with implications for skills development. This research sought to answer the question: What is the theoretical and practical history and current constitution of the agricultural extension officer occupation as a mediating unit of intervention for VET skills planning, and is it adequate for climate resilience? The study addressed five objectives. First, the study undertook a historical review of occupation as a mediating unit of intervention for skills planning. Secondly, the study examined current descriptions of the extension occupation as used for skills planning in Africa. Thirdly, in order to better understand the operationalisation of this skills planning instrument, the study examined aspects of skills development, specifically how VET preparation for extension work was taking place in response to the need for climate resilience through a curriculum review and the experiences and related work activities of extension services actors. The study also reviewed agricultural extension and VET policy, and labour market data for its responsiveness to climate resilience. In response to the findings of Objectives 1-4, a fifth objective was developed to offer expanded possibilities for a mediating unit of intervention for skills planning and development relevant to climate resilience in agricultural extension, as this appeared to be needed. To develop the study, I drew on the Social Ecosystems Model (SEM) for skills, which raises the issue of mediation in skills development. I also drew on Cultural-Historical Activity Theory (CHAT) to help theorise the mediation in the SEM for skills, where different activity systems (policy, training and extension, farming) were present. This framework allowed me to probe how these activity systems were mediating climate-resilient skills development with/for extension services (or not). Empirical data was produced through secondary and primary data, generated in two case study contexts using a cross-case design. Documentary analysis involved analysing policy documents, study curricula and historical literature to develop an understanding of historical sociology of occupation as a skills planning mediating unit and insight into contemporary understanding of how occupational frameworks are structured and deployed. Analysis was undertaken in two stages; firstly, through in-depth cases of occupation as mediating unit of intervention for skills planning, and aspects of skills development as influenced by this as influenced by this mediating unit (Chapter 5 and 6). This offered a first layer of analysis and insights into temporality, verticalities, mediation and horizontalities in the SEM for skills in each case. Secondly, abduction was undertaken to build models of the SEM for skills as found in each of the two countries using the SEM and CHAT analytical tools (Chapter 7), showing the need for skills planning tools that are more closely related to and relevant to the contexts of skills development. Findings revealed insights into the SEM for skills related to ecological time, notably a mismatch between the cultural-historical time of occupational skills planning and development, and the temporal demands for climate resilience. Historical analysis the deep rootedness of occupations and occupational structures in colonial histories and traditions, going back as far as the medieval era, with current occupations still bearing features of ancient occupational guild practices and hence not adequately responsive to climate change, affecting the SEM for skills in both cases and producing contradictions. Analysis further revealed that contemporary agricultural extension in Africa is decentralised and pluralistic, with few extension-related policies employed underdeveloped. Labour market in both South Africa and Uganda are not adequately orientated to climate resilience and fail to include climate resilience expertise, despite a need for this amongst farmers and by policy, revealing contradictions between various policy activity systems, which are not adequately facilitating. Empirical findings from study sites revealed that VET preparation for extension work lacks responsiveness to climate resilience within the skills ecosystem. Consequently, extension officers lack expertise in climate resilience, which is an increasing demand expressed by farmers and other horizontal activity systems in the SEM for skills. Through a more complex understanding of the extension officer occupation and its development in skills ecosystem in Africa, the study proposes a broader mediating unit of intervention for skills planning than that of ‘occupation’ only. The mediating unit of intervention put forward for skills planning is a workstream mapping approach for climate resilient extension training in VET. This planning approach has implications for skills development viewed as work, learning and living involving more than one activity system in the skills development landscape, thus also broadening the approach to VET. The study concludes with recommendations to further test this approach. Finally, it makes recommendations that can inform: 1) curriculum innovation, 2) extension practice, 3) policy, and 4) research. , Thesis (PhD) -- Faculty of Education, Secondary and Post School Education, 2024
- Full Text:
- Date Issued: 2024-04-05
Plankton and macroinvertebrate dynamics in the Khakhea–Bray transboundary aquifer region
- Mungenge, Chipo Perseverance
- Authors: Mungenge, Chipo Perseverance
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435674 , vital:73178 , DOI 10.21504/10962/435674
- Description: Temporary wetlands are prevalent in semi–arid and arid climates across the globe and harbour unique faunal assemblages that significantly contribute to regional aquatic biodiversity. This study aims to enhance our understanding of the ecological dynamics of temporary wetland ecosystems, focusing on plankton dynamics, large branchiopod diversity, trophic dynamics, water quality and the impacts of freshwater salinisation in temporary pans in the Khakhea Bray Transboundary aquifer region in the North west Province, South Africa. This body of work represents field, laboratory and writing components which span the period May 2021 to December 2023. The results from this study revealed seasonal patterns in plankton diversity with a winter peak in phytoplankton diversity dominated by Zygnematophyceae species, while Chlorophyceae were dominant in summer. Zooplankton diversity was high in summer as compared to winter, with both Rotifera and Copepoda dominant in both seasons. Six large branchiopod species were found in the region, and three of these were new distribution records for the North west Province, including the first record of Phallocryptus spinosa in the salt pan that was sampled in summer. Large branchiopod diversity was mainly influenced by water temperature and phosphorous in summer, while sediment sodium influenced the diversity in winter. The stable isotope analyses used to determine trophic dynamics in these temporary pans revealed that the food web had four trophic levels, with the top predators being the notonectids Anisops sp. The dominant consumers were predatory insects such as Sigara sp., Anisops sp., Lestes sp., Rhantus sp. and Cybister sp. adults and larvae, as well as detritivorous Tomopterna sp. tadpoles. High trophic niche overlaps were found between the notonectids and the dytiscids. These temporary pans are susceptible to anthropogenic impacts, and disturbed pans were found to have elevated pH, ammonium, phosphates and dissolved oxygen compared to the undisturbed pans. A strong positive relationship was observed between chl–a and temperature, pH, dissolved oxygen, phosphates and ammonium. Chlorophyll–a concentration increased as surface area and the distance from kraals, buildings and latrines decreased. Freshwater salinisation was found to cause notable shifts in abiotic factors and benthic phytoplankton communities, favouring the proliferation of saline–tolerant diatom species at the cost of more sensitive taxa. The study also revealed that in interaction with salinisation, time also exerted a notable influence on shaping the benthic phytoplankton community. Salinity levels of 2.5 ppt and above led to significant decreases in emergent taxa richness and abundance, with Spinicaudata and Ostracoda being the most sensitive taxa to high salinities. There was a limited effect on community hatching phenology dynamics from salinity. This suggests that the main impact of salinisation in these systems will be reductions in hatching success and, hence, reduced recruitment. The study highlights the vulnerability of temporary pan ecosystems to anthropogenic influences and the complexities of interactions of organisms and the environmental conditions in these systems. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Mungenge, Chipo Perseverance
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435674 , vital:73178 , DOI 10.21504/10962/435674
- Description: Temporary wetlands are prevalent in semi–arid and arid climates across the globe and harbour unique faunal assemblages that significantly contribute to regional aquatic biodiversity. This study aims to enhance our understanding of the ecological dynamics of temporary wetland ecosystems, focusing on plankton dynamics, large branchiopod diversity, trophic dynamics, water quality and the impacts of freshwater salinisation in temporary pans in the Khakhea Bray Transboundary aquifer region in the North west Province, South Africa. This body of work represents field, laboratory and writing components which span the period May 2021 to December 2023. The results from this study revealed seasonal patterns in plankton diversity with a winter peak in phytoplankton diversity dominated by Zygnematophyceae species, while Chlorophyceae were dominant in summer. Zooplankton diversity was high in summer as compared to winter, with both Rotifera and Copepoda dominant in both seasons. Six large branchiopod species were found in the region, and three of these were new distribution records for the North west Province, including the first record of Phallocryptus spinosa in the salt pan that was sampled in summer. Large branchiopod diversity was mainly influenced by water temperature and phosphorous in summer, while sediment sodium influenced the diversity in winter. The stable isotope analyses used to determine trophic dynamics in these temporary pans revealed that the food web had four trophic levels, with the top predators being the notonectids Anisops sp. The dominant consumers were predatory insects such as Sigara sp., Anisops sp., Lestes sp., Rhantus sp. and Cybister sp. adults and larvae, as well as detritivorous Tomopterna sp. tadpoles. High trophic niche overlaps were found between the notonectids and the dytiscids. These temporary pans are susceptible to anthropogenic impacts, and disturbed pans were found to have elevated pH, ammonium, phosphates and dissolved oxygen compared to the undisturbed pans. A strong positive relationship was observed between chl–a and temperature, pH, dissolved oxygen, phosphates and ammonium. Chlorophyll–a concentration increased as surface area and the distance from kraals, buildings and latrines decreased. Freshwater salinisation was found to cause notable shifts in abiotic factors and benthic phytoplankton communities, favouring the proliferation of saline–tolerant diatom species at the cost of more sensitive taxa. The study also revealed that in interaction with salinisation, time also exerted a notable influence on shaping the benthic phytoplankton community. Salinity levels of 2.5 ppt and above led to significant decreases in emergent taxa richness and abundance, with Spinicaudata and Ostracoda being the most sensitive taxa to high salinities. There was a limited effect on community hatching phenology dynamics from salinity. This suggests that the main impact of salinisation in these systems will be reductions in hatching success and, hence, reduced recruitment. The study highlights the vulnerability of temporary pan ecosystems to anthropogenic influences and the complexities of interactions of organisms and the environmental conditions in these systems. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
The influence of the physical environment on invertebrate larval transport, settlement and recruitment with insights on early-stage physiological performance
- Authors: Duna, Oliver Olwethu
- Date: 2024-04-05
- Subjects: Larvae Physiology , Bivalves , Invertebrates Habitat , Larvae Dispersal , Biological oceanography , Larvae Geographical distribution
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435663 , vital:73177 , DOI 10.21504/10962/435663
- Description: Most marine benthic organisms have a biphasic life cycle whereby the larvae are pelagic, and their distribution, transport and settlement are largely controlled by environmental factors. Among these factors, hydrodynamics have key direct effects. Nearshore water hydrodynamics are strongly influenced by wind. This study investigated whether wind indirectly affects the distribution, settlement and recruitment of invertebrate marine larvae. Additionally, larvae are exposed to a more constant, benign environment than they will experience after settlement, and therefore the possible effects of larval thermal history on the physiological plasticity of settled organisms was also estimated for possible long-term insights into population dynamics. Four sites, two on the western and two on the eastern side of Algoa Bay in Gqeberha (formerly known as Port Elizabeth), South Africa, were chosen for larval collection. Sites at opposite ends of the bay were selected as they were towards either side of the dominant wind directions in this region. At each site, two sampling stations were identified at 300 and 900 metres offshore, with station replicates 300 metres apart. Sampling of marine invertebrate larvae was conducted after two days of westerly or easterly winds at either of the two western or eastern sites. The number of hours of unidirectional wind determined the prevalent wind on the two days prior to sampling. Samples were collected with a plankton pump at three depths; surface, mid-depth and bottom. Simultaneously with plankton sampling, water properties (fluorescence, temperature, zonal and meridional flow, salinity and oxygen) were measured. Settlement/recruitment samples of mussels and barnacles were collected at six sites, two at either edge of the bay and two within the center of the bay. Plastic scouring pads and PVC plastic plates covered with safety-walk, placed at least 30 cm from each other, were used to collect settlers/recruits of mussels and barnacles, respectively. The pads and plates were replaced on a monthly basis for 14 months to quantify monthly settlement/recruitment. At four of the six sites used for quantifying settlement/recruitment, settlers and recruits were collected to measure the physiological responses of these two ontogenetic stages (settlers and recruits) to acute temperature variations which they might experience in the intertidal zone. Three temperature loggers were used to record real time temperature variation at each site over the period (one month) in which the artificial collectors were in position. Factorial ANOVA was used to investigate the effects of wind, depth, site, and distance from the shore on the abundance of larvae in the water column, as well as the effects of month and site on settlement/recruitment. Additionally, multiple regression analyses were used to investigate the effects of physical parameters, including upwelling and dissipation of turbulent kinetic energy, on the abundance of both larvae, settlers and recruits. Distance-based linear models and redundancy analyses were also carried out on the abundances of invertebrate larvae. Correlation analyses were performed to investigate the effect of the number of hours of directional wind on settlement. Lastly, correlation analyses between wind and currents were carried out. The results revealed a link between winds and currents, with wind speed directly proportional to surface current speed, which, as expected, decreased with depth. Current direction was, however, not perfectly aligned with wind direction. Larval distribution, settlement and recruitment were largely associated with the nearshore dissipation of turbulent kinetic energy and upwelling. Thus, overall larval, settler and recruit abundances were indirectly affected by wind. Physiologically, there was no significant difference in oxygen consumption between the juvenile ontogenetic stages (settlers and recruits) of mussels. Recruits exposed to average and maximum temperatures, however, consumed more oxygen than those exposed to low temperatures. Wind and wind-mediated currents as well as temperature have been shown to shape the distribution and shore supply of larvae, and this study contributes to the broad knowledge of population dynamics and replenishment, and the tight relation of abiotic factors affecting biological processes on the shore. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Duna, Oliver Olwethu
- Date: 2024-04-05
- Subjects: Larvae Physiology , Bivalves , Invertebrates Habitat , Larvae Dispersal , Biological oceanography , Larvae Geographical distribution
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435663 , vital:73177 , DOI 10.21504/10962/435663
- Description: Most marine benthic organisms have a biphasic life cycle whereby the larvae are pelagic, and their distribution, transport and settlement are largely controlled by environmental factors. Among these factors, hydrodynamics have key direct effects. Nearshore water hydrodynamics are strongly influenced by wind. This study investigated whether wind indirectly affects the distribution, settlement and recruitment of invertebrate marine larvae. Additionally, larvae are exposed to a more constant, benign environment than they will experience after settlement, and therefore the possible effects of larval thermal history on the physiological plasticity of settled organisms was also estimated for possible long-term insights into population dynamics. Four sites, two on the western and two on the eastern side of Algoa Bay in Gqeberha (formerly known as Port Elizabeth), South Africa, were chosen for larval collection. Sites at opposite ends of the bay were selected as they were towards either side of the dominant wind directions in this region. At each site, two sampling stations were identified at 300 and 900 metres offshore, with station replicates 300 metres apart. Sampling of marine invertebrate larvae was conducted after two days of westerly or easterly winds at either of the two western or eastern sites. The number of hours of unidirectional wind determined the prevalent wind on the two days prior to sampling. Samples were collected with a plankton pump at three depths; surface, mid-depth and bottom. Simultaneously with plankton sampling, water properties (fluorescence, temperature, zonal and meridional flow, salinity and oxygen) were measured. Settlement/recruitment samples of mussels and barnacles were collected at six sites, two at either edge of the bay and two within the center of the bay. Plastic scouring pads and PVC plastic plates covered with safety-walk, placed at least 30 cm from each other, were used to collect settlers/recruits of mussels and barnacles, respectively. The pads and plates were replaced on a monthly basis for 14 months to quantify monthly settlement/recruitment. At four of the six sites used for quantifying settlement/recruitment, settlers and recruits were collected to measure the physiological responses of these two ontogenetic stages (settlers and recruits) to acute temperature variations which they might experience in the intertidal zone. Three temperature loggers were used to record real time temperature variation at each site over the period (one month) in which the artificial collectors were in position. Factorial ANOVA was used to investigate the effects of wind, depth, site, and distance from the shore on the abundance of larvae in the water column, as well as the effects of month and site on settlement/recruitment. Additionally, multiple regression analyses were used to investigate the effects of physical parameters, including upwelling and dissipation of turbulent kinetic energy, on the abundance of both larvae, settlers and recruits. Distance-based linear models and redundancy analyses were also carried out on the abundances of invertebrate larvae. Correlation analyses were performed to investigate the effect of the number of hours of directional wind on settlement. Lastly, correlation analyses between wind and currents were carried out. The results revealed a link between winds and currents, with wind speed directly proportional to surface current speed, which, as expected, decreased with depth. Current direction was, however, not perfectly aligned with wind direction. Larval distribution, settlement and recruitment were largely associated with the nearshore dissipation of turbulent kinetic energy and upwelling. Thus, overall larval, settler and recruit abundances were indirectly affected by wind. Physiologically, there was no significant difference in oxygen consumption between the juvenile ontogenetic stages (settlers and recruits) of mussels. Recruits exposed to average and maximum temperatures, however, consumed more oxygen than those exposed to low temperatures. Wind and wind-mediated currents as well as temperature have been shown to shape the distribution and shore supply of larvae, and this study contributes to the broad knowledge of population dynamics and replenishment, and the tight relation of abiotic factors affecting biological processes on the shore. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-05
Developing a community of practice to promote the use of biological control in the integrated management of Prosopis in South Africa
- Authors: Van Staden, Gretha
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434998 , vital:73122
- Description: Prosopis spp. are non-native species present in the arid parts of southern Africa. These trees originated in the Americas and were first introduced as a source of fodder, shade, and wood, but have become invasive, negatively impacting local biodiversity, and disrupting the delivery of ecosystem services. Some species of Prosopis hybridise freely, complicating identification and subsequent control. The control of Prosopis in the Northern Cape Province of South Africa is still contentious, because of the perceived benefits to some landowners. The effectiveness of biological control agents to control the spread of Prosopis has been quantified, more damaging agents have been considered in recent years because of the continued increase in Prosopis density. Research into the establishment of a Community of Practice (CoP) to address the differences in perceptions regarding the control of Prosopis in the Northern Cape Province is considered an appropriate starting point to conceptualise the challenges to the successful integrated management of Prosopis. As farmers are the main stakeholders involved with Prosopis control, understanding the role of farmers and the functioning of farming enterprises in the Northern Cape is imperative for the development of both a CoP as well as the appropriate management of Prosopis. To foster engagement with as many stakeholders as possible, workshops dealing with biological control as part on an integrated approach to the control of Prosopis were held in towns in the Northern Cape Province: Groblershoop, Brandvlei, Kenhardt, Upington, Prieska and Williston. Some of the main concerns of the landusers include the host specificity of the released biocontrol agents, as well as increased transparency and communication. This is especially in regards to the research on present and future biological control agents that will possibly improve the perceptions of stakeholders. The mechanical harvesting and use of biomass as a control method was supported, especially where farmers were removing Prosopis from their properties, leaving large amounts of biomass in the veld. Continued research into Prosopis in the Northern Cape needs to consider the possibility of secondary invasions, especially in areas where native bush encroachment is already a concern. The impact of clearing in terms of natural grazing and animal improvement needs to be quantified, to conceptualise the importance of maintaining better veld quality versus using Prosopis for fodder. Biological control targeting not only the reproductive output of the trees, but also the standing biomass has support from the majority of the land users in the Northern Cape Province following these workshops and this study shows the importance of a socio-ecological approach to the control of landscape scale invasion. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Van Staden, Gretha
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434998 , vital:73122
- Description: Prosopis spp. are non-native species present in the arid parts of southern Africa. These trees originated in the Americas and were first introduced as a source of fodder, shade, and wood, but have become invasive, negatively impacting local biodiversity, and disrupting the delivery of ecosystem services. Some species of Prosopis hybridise freely, complicating identification and subsequent control. The control of Prosopis in the Northern Cape Province of South Africa is still contentious, because of the perceived benefits to some landowners. The effectiveness of biological control agents to control the spread of Prosopis has been quantified, more damaging agents have been considered in recent years because of the continued increase in Prosopis density. Research into the establishment of a Community of Practice (CoP) to address the differences in perceptions regarding the control of Prosopis in the Northern Cape Province is considered an appropriate starting point to conceptualise the challenges to the successful integrated management of Prosopis. As farmers are the main stakeholders involved with Prosopis control, understanding the role of farmers and the functioning of farming enterprises in the Northern Cape is imperative for the development of both a CoP as well as the appropriate management of Prosopis. To foster engagement with as many stakeholders as possible, workshops dealing with biological control as part on an integrated approach to the control of Prosopis were held in towns in the Northern Cape Province: Groblershoop, Brandvlei, Kenhardt, Upington, Prieska and Williston. Some of the main concerns of the landusers include the host specificity of the released biocontrol agents, as well as increased transparency and communication. This is especially in regards to the research on present and future biological control agents that will possibly improve the perceptions of stakeholders. The mechanical harvesting and use of biomass as a control method was supported, especially where farmers were removing Prosopis from their properties, leaving large amounts of biomass in the veld. Continued research into Prosopis in the Northern Cape needs to consider the possibility of secondary invasions, especially in areas where native bush encroachment is already a concern. The impact of clearing in terms of natural grazing and animal improvement needs to be quantified, to conceptualise the importance of maintaining better veld quality versus using Prosopis for fodder. Biological control targeting not only the reproductive output of the trees, but also the standing biomass has support from the majority of the land users in the Northern Cape Province following these workshops and this study shows the importance of a socio-ecological approach to the control of landscape scale invasion. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
Functional significance of mixed-species groups for zebra (Equus quagga) in savanna habitats
- Corry-Roberts, Carys Alexandra
- Authors: Corry-Roberts, Carys Alexandra
- Date: 2024-04-04
- Subjects: Herding behavior in animals , Zebras Food , Foraging , Zebras Behavior , Zebras Conservation , Herbivores Habitat
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434925 , vital:73116
- Description: Globally, herbivore populations are facing decline, which threatens their crucial role within the ecosystems they inhabit. Herbivores are essential to ecosystem structure and function because they act as prey for higher trophic levels, cycle soil nutrients, and alter vegetation structure. Understanding the drivers that shape herbivore habitat use and selection are therefore critical for making informed conservation and management decisions. Like all prey species, herbivores must balance a trade-off between acquiring resources and avoiding predation which is influenced by a number of species-specific intrinsic traits and various ecological drivers. Herbivores can also track risk over space and time, and certain habitat structures and landscape features can influence risk perception; this is termed the landscape of fear. To mitigate the risk-reward trade-off, herbivores employ a suite of behavioural responses. Group formation is likely the most well-documented of these responses. However, grouping results in the information-competition trade-off, wherein group members may obtain valuable information regarding the location of resources and/or the risk of predation, but may suffer from increased competition, especially among larger group sizes. Mixed-species groups—an assemblage of two or more species in close spatial association—have the potential to mitigate some of the competitive costs of larger conspecific groups and enhance the anti-predator and/or foraging benefits of grouping. African savannas provide a particularly useful natural laboratory to study mixed-species groups, due to the high diversity of prey species and habitat heterogeneity present. Previous studies have investigated the mixed-species effect within these systems, but have yet to quantify some of the identity-dependent costs and benefits associated with mixed-species herding. Thus, the overall aim of my study was to quantify the functional significance of mixed-species groups for zebra (Equus quagga) herding with two of their most common herding partners, impala (Aepyceros melampus) and wildebeest (Connochaetes taurinus). My study was conducted at multiple spatial scales in the southern portion of the Kruger National Park, South Africa between 2021 and 2022. I found that mixed-species herding altered zebra landscape use, resulting in a quantifiable intensification of habitat use compared to when they herd with conspecifics. I did not observe significant habitat expansion for zebra in mixed-species herds compared to single-species herds, likely because the anti-predator benefits of mixed-species herding convey enhanced foraging opportunities in already-safe habitats. Zebra foraging with impala achieved greater foraging success and experienced lower levels of competition, compared to zebra foraging with wildebeest. However, compared to foraging with conspecifics, the levelled landscape of fear zebra experienced when foraging with wildebeest resulted in increased foraging success across the landscape. My findings highlight the context-dependency of the costs and benefits associated with different herding partners for zebra, and suggest that in mixed-species herds with wildebeest, zebra experience increased potential fitness benefits compared to herding with impala or conspecifics. Overall, the findings of my study suggest that mixed-species herding is an important tool in the suite of anti-predator behaviours employed by prey species, and one with significant implications for survivorship, habitat use, and ultimately, community level interactions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Corry-Roberts, Carys Alexandra
- Date: 2024-04-04
- Subjects: Herding behavior in animals , Zebras Food , Foraging , Zebras Behavior , Zebras Conservation , Herbivores Habitat
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434925 , vital:73116
- Description: Globally, herbivore populations are facing decline, which threatens their crucial role within the ecosystems they inhabit. Herbivores are essential to ecosystem structure and function because they act as prey for higher trophic levels, cycle soil nutrients, and alter vegetation structure. Understanding the drivers that shape herbivore habitat use and selection are therefore critical for making informed conservation and management decisions. Like all prey species, herbivores must balance a trade-off between acquiring resources and avoiding predation which is influenced by a number of species-specific intrinsic traits and various ecological drivers. Herbivores can also track risk over space and time, and certain habitat structures and landscape features can influence risk perception; this is termed the landscape of fear. To mitigate the risk-reward trade-off, herbivores employ a suite of behavioural responses. Group formation is likely the most well-documented of these responses. However, grouping results in the information-competition trade-off, wherein group members may obtain valuable information regarding the location of resources and/or the risk of predation, but may suffer from increased competition, especially among larger group sizes. Mixed-species groups—an assemblage of two or more species in close spatial association—have the potential to mitigate some of the competitive costs of larger conspecific groups and enhance the anti-predator and/or foraging benefits of grouping. African savannas provide a particularly useful natural laboratory to study mixed-species groups, due to the high diversity of prey species and habitat heterogeneity present. Previous studies have investigated the mixed-species effect within these systems, but have yet to quantify some of the identity-dependent costs and benefits associated with mixed-species herding. Thus, the overall aim of my study was to quantify the functional significance of mixed-species groups for zebra (Equus quagga) herding with two of their most common herding partners, impala (Aepyceros melampus) and wildebeest (Connochaetes taurinus). My study was conducted at multiple spatial scales in the southern portion of the Kruger National Park, South Africa between 2021 and 2022. I found that mixed-species herding altered zebra landscape use, resulting in a quantifiable intensification of habitat use compared to when they herd with conspecifics. I did not observe significant habitat expansion for zebra in mixed-species herds compared to single-species herds, likely because the anti-predator benefits of mixed-species herding convey enhanced foraging opportunities in already-safe habitats. Zebra foraging with impala achieved greater foraging success and experienced lower levels of competition, compared to zebra foraging with wildebeest. However, compared to foraging with conspecifics, the levelled landscape of fear zebra experienced when foraging with wildebeest resulted in increased foraging success across the landscape. My findings highlight the context-dependency of the costs and benefits associated with different herding partners for zebra, and suggest that in mixed-species herds with wildebeest, zebra experience increased potential fitness benefits compared to herding with impala or conspecifics. Overall, the findings of my study suggest that mixed-species herding is an important tool in the suite of anti-predator behaviours employed by prey species, and one with significant implications for survivorship, habitat use, and ultimately, community level interactions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
The effect of Gracilaria gracilis (Rhodophyta) on growth and behaviour of farmed abalone Haliotis midae when included in the abalone diet
- Madlala, Njabulo Praiseworth
- Authors: Madlala, Njabulo Praiseworth
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435332 , vital:73148
- Description: Abalone feed naturally on algae, but commercial abalone farms rely on formulated feed. The inclusion of algae with the formulated feed in the diet improves growth, health and feed conversion ratio (FCR). However, the kelp that is currently included in the feed is wild harvested and this resource is limited and under increasing pressure. Thus, there is a need to develop an alternative sustainable source of algae. The aim was to use Gracilaria gracilis algae (that was produced with mussel in an integrated multitrophic aquaculture system; IMTA) which was then included into abalone feeds and its influence on abalone growth, FCR and behaviour was evaluated. Sea-based G. gracilis was harvested off an existing IMTA system, manufactured into Abfeed® and fed to abalone to determine growth efficiency. Abalone (30 - 40 g abalone-1) originated from the same cohort at Whale Rock Abalone Farm (Pty) Ltd., Hermanus. Abalone were fed either: Abfeed® S34 only with no algae (G0, the control); Abfeed® with sea-based IMTA G. gracilis included in the formulated feed at 0.75 % (G0.75); 1.50 % (G1.50); 3.00 % (G3.00); 6.00 % (G6.00); and 12.00 % (G12.00) inclusion; and Abfeed® S34 with fresh-live G. gracilis (cultured at Whale Rock Abalone Farm (Pty) Ltd.; Gfresh + S34s). Abalone shell length, whole body mass and FCR were measured at a four-months interval over eight months (two growth cycles). Differences in behaviour (i.e., level of activity and feeding activity) were also monitored and comparing between treatments. There was significant difference in mean whole-body mass between treatments (RMANOVA, F(6, 29) = 3.71, p = 0.007). Abalone fed the diet with the highest inclusion of dry G. gracilis (G12.00) had a lower mean whole-body mass value (74.13 ± 2.94 g abalone-1) than abalone from all the other diets after eight months. There was a negative relationship between the condition factor and dry G. gracilis inclusion rate for the first growth cycle (y = - 0.0044x + 1.222, R2 = 0.24, p=0.009) and second-growth cycle (y = - 0.0096x + 1.2233, R2 = 0.51, p = 0.00002). Abalone receiving fresh G. gracilis were less quiescent and more alert on the first hours after food distribution (p < 0.05). The same proportion of abalone with G0, G0.75, and G6.00 G. gracilis inclusion were feeding all along the 9 hours post-feeding. This study will potentially reduce the dependence of abalone farms on wild-harvested kelp in formulated feed. This will improve their contribution to a more environmentally sustainable global production of sea food products, making them more competitive on international markets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Madlala, Njabulo Praiseworth
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/435332 , vital:73148
- Description: Abalone feed naturally on algae, but commercial abalone farms rely on formulated feed. The inclusion of algae with the formulated feed in the diet improves growth, health and feed conversion ratio (FCR). However, the kelp that is currently included in the feed is wild harvested and this resource is limited and under increasing pressure. Thus, there is a need to develop an alternative sustainable source of algae. The aim was to use Gracilaria gracilis algae (that was produced with mussel in an integrated multitrophic aquaculture system; IMTA) which was then included into abalone feeds and its influence on abalone growth, FCR and behaviour was evaluated. Sea-based G. gracilis was harvested off an existing IMTA system, manufactured into Abfeed® and fed to abalone to determine growth efficiency. Abalone (30 - 40 g abalone-1) originated from the same cohort at Whale Rock Abalone Farm (Pty) Ltd., Hermanus. Abalone were fed either: Abfeed® S34 only with no algae (G0, the control); Abfeed® with sea-based IMTA G. gracilis included in the formulated feed at 0.75 % (G0.75); 1.50 % (G1.50); 3.00 % (G3.00); 6.00 % (G6.00); and 12.00 % (G12.00) inclusion; and Abfeed® S34 with fresh-live G. gracilis (cultured at Whale Rock Abalone Farm (Pty) Ltd.; Gfresh + S34s). Abalone shell length, whole body mass and FCR were measured at a four-months interval over eight months (two growth cycles). Differences in behaviour (i.e., level of activity and feeding activity) were also monitored and comparing between treatments. There was significant difference in mean whole-body mass between treatments (RMANOVA, F(6, 29) = 3.71, p = 0.007). Abalone fed the diet with the highest inclusion of dry G. gracilis (G12.00) had a lower mean whole-body mass value (74.13 ± 2.94 g abalone-1) than abalone from all the other diets after eight months. There was a negative relationship between the condition factor and dry G. gracilis inclusion rate for the first growth cycle (y = - 0.0044x + 1.222, R2 = 0.24, p=0.009) and second-growth cycle (y = - 0.0096x + 1.2233, R2 = 0.51, p = 0.00002). Abalone receiving fresh G. gracilis were less quiescent and more alert on the first hours after food distribution (p < 0.05). The same proportion of abalone with G0, G0.75, and G6.00 G. gracilis inclusion were feeding all along the 9 hours post-feeding. This study will potentially reduce the dependence of abalone farms on wild-harvested kelp in formulated feed. This will improve their contribution to a more environmentally sustainable global production of sea food products, making them more competitive on international markets. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
- Full Text:
- Date Issued: 2024-04-04
The mediating role of generational difference on the relationship between psychological capital, psychological empowerment, organisational support and the wellbeing of South African National Defence Force members
- Authors: Selepe, Babitsanang Annah
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435616 , vital:73173 , DOI 10.21504/10962/435616
- Description: There is a growing concern in understanding the contribution of generational difference (as a mediating variable) and factors that increase soldiers' well-being. This study aimed to determine the relationship between Psychological Capital, Psychological Empowerment and Organisational Support, and well-being. Additionally, it proposes the generational differences as a potential mediating factor among these variables. The study was guided by a positivist philosophy and quantitative research method was employed. The sample for this research consisted of 777 members from both Internal deployed within borders of Free state and those going for external deployment at De-Brug. The results show most respondents were male (78.3%) and 21.7% female. Most respondents were categorised as Gen Y (between 1981 - 1996, 67.0%), followed by Gen X (1965 - 1980, 24.8%) and Gen Z (1997 - 2012, 8.2%). Most respondents were in the SA Army, followed by SAAF and SAMHS and the SA Navy. Spearman’s Correlation and ANOVA analyses were conducted to test the relationship between the variables. The results revealed significant relationships between the variables included in the empirical model. However, Well-being does not have a statistically significant correlation with the mediation variable, generation cohort. Similarly, generation cohorts (X, Y, Z) do not significantly correlate with the predictor variables, Perceived Organisational Support, Psychological Empowerment. However, there is a statistically significant small negative correlation between generation cohort (Age) and Psychological Capital. The multiple regression analysis exhibited a significant overall model fit, indicating that 30% of the variance in employee well-being was accounted for by the predictors. Thus, this research implicates that the South African National Defence Force (SANDF) would benefit from developing a culture and adopting policies as well as programmes that prioritises psychological well-being above physical prowess. For this reason, the present study is regarded as offering a potentially valuable contribution to the existing body of research in the positive psychology and reveals practical implications and applications within the military context. The study recommends that combat readiness requires prioritising mental health above physical strength. Policymakers should consider psychological factors like psychological capital and psychological 6 empowerment. Training programmes should include Psychological Capital and cognitive resilience. There should also be further research on positive psychology and troops' well-being. These factors can help improve peacekeeping and combat force readiness. Understanding generational variations' mediating effect can inform resilience and training programmes. Military organisations should cultivate confident, capable, and educated leaders to improve military proficiency. , Thesis (PhD) -- Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Selepe, Babitsanang Annah
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435616 , vital:73173 , DOI 10.21504/10962/435616
- Description: There is a growing concern in understanding the contribution of generational difference (as a mediating variable) and factors that increase soldiers' well-being. This study aimed to determine the relationship between Psychological Capital, Psychological Empowerment and Organisational Support, and well-being. Additionally, it proposes the generational differences as a potential mediating factor among these variables. The study was guided by a positivist philosophy and quantitative research method was employed. The sample for this research consisted of 777 members from both Internal deployed within borders of Free state and those going for external deployment at De-Brug. The results show most respondents were male (78.3%) and 21.7% female. Most respondents were categorised as Gen Y (between 1981 - 1996, 67.0%), followed by Gen X (1965 - 1980, 24.8%) and Gen Z (1997 - 2012, 8.2%). Most respondents were in the SA Army, followed by SAAF and SAMHS and the SA Navy. Spearman’s Correlation and ANOVA analyses were conducted to test the relationship between the variables. The results revealed significant relationships between the variables included in the empirical model. However, Well-being does not have a statistically significant correlation with the mediation variable, generation cohort. Similarly, generation cohorts (X, Y, Z) do not significantly correlate with the predictor variables, Perceived Organisational Support, Psychological Empowerment. However, there is a statistically significant small negative correlation between generation cohort (Age) and Psychological Capital. The multiple regression analysis exhibited a significant overall model fit, indicating that 30% of the variance in employee well-being was accounted for by the predictors. Thus, this research implicates that the South African National Defence Force (SANDF) would benefit from developing a culture and adopting policies as well as programmes that prioritises psychological well-being above physical prowess. For this reason, the present study is regarded as offering a potentially valuable contribution to the existing body of research in the positive psychology and reveals practical implications and applications within the military context. The study recommends that combat readiness requires prioritising mental health above physical strength. Policymakers should consider psychological factors like psychological capital and psychological 6 empowerment. Training programmes should include Psychological Capital and cognitive resilience. There should also be further research on positive psychology and troops' well-being. These factors can help improve peacekeeping and combat force readiness. Understanding generational variations' mediating effect can inform resilience and training programmes. Military organisations should cultivate confident, capable, and educated leaders to improve military proficiency. , Thesis (PhD) -- Humanities, Psychology, 2024
- Full Text:
- Date Issued: 2024-04-04
The use of gabions as a tool for ecological engineering
- Authors: Seath, Jessica Lauren
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434987 , vital:73121
- Description: Anthropogenic activities are centred in coastal ecosystems, including the development of harbours and/or marinas. The artificial structures used in coastal development typically has a different composition, orientation and level of complexity to that of natural ecosystems contributing to loss of biodiversity and increased incidence of invasive species. Ecological engineering research is attempting to identify different types of structures and materials that can increase species diversity and target species of conservation concern in coastal systems. The aim of this study was to investigate the efficacy of gabions (rock filled structures) as an ecological engineering tool by comparing community structure on these structures with pre-existing seawall structures within a small harbour and marina in South Africa (Knysna Harbour). The objectives of the study were to compare the differences in; 1) fish and; 2) colonising organisms’ diversity and composition between two artificial structures. Thirteen gabion boxes were deployed in Knysna Harbour and together with corresponding seawalls, monitored quarterly over a period of 12 months (August 2020 – August 2021) to assess taxon and functional richness, diversity, abundance and composition of fish, invertebrate and algal species. Physico-chemical characteristics of the water body were also monitored quarterly. Remote underwater video systems were used to quantify MaxN (maximum number of a fish species in the frame at any one time during each set that gives an indication of relative abundance) and identify fish species. The results of the two-way crossed ANOVAs indicated that gabion habitats recruited greater numbers and more types of fish species and from more functional groups than the seawalls, especially omnivorous and carnivorous fish. Additionally, photoquadrats were used to quantify percentage cover, counts and to identify colonising taxa. The results of the two-way crossed ANOVAs indicated that gabions hosted greater numbers of species resulting in a higher overall diversity and abundance of colonising organisms than seawalls. By contrast, the seawalls supported more types of functional groups of colonising organisms than gabions, largely due to abundances of different algal species. The results from the crossed PERMANOVAs indicated that the composition of fish and colonising organisms were vastly different from one another, and that each habitat was supporting very different functional groups. Results indicate that whilst both gabions and seawalls contain several alien species, that the ratio of native to alien species is higher in gabion habitats. Additionally, this research observed that gabion structures hosted four species listed on the IUCN Red List of Threatened Species. This study has highlighted that the use of gabions (with their natural increased complexity) could be important to consider for the future of urban coastal development in harbours such as in Knysna Harbour. Ecological engineering projects using gabions have the potential to be used in South Africa in projects that aim at increasing biodiversity in urban coastal environments. As well as increasing the settlement and abundance of habitat-forming ecosystem engineers to ensure the long-term stability of these ecosystems. They can be used both in the development of new costal development projects as well as in an ad-hoc fashion where they can be interspersed on seawalls in harbours. Additionally, gabions have the potential to be used in projects that target species of conservation concern such as the endangered Knysna Seahorse (Hippocampus capensis). It is, however, important to monitor the invasion by non-native species in future ecological engineering projects in South Africa as well as their potential for creating ecological traps (a situation in which an organism may be convinced to settle in a low-quality habitat) for certain species. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
- Authors: Seath, Jessica Lauren
- Date: 2024-04-04
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/434987 , vital:73121
- Description: Anthropogenic activities are centred in coastal ecosystems, including the development of harbours and/or marinas. The artificial structures used in coastal development typically has a different composition, orientation and level of complexity to that of natural ecosystems contributing to loss of biodiversity and increased incidence of invasive species. Ecological engineering research is attempting to identify different types of structures and materials that can increase species diversity and target species of conservation concern in coastal systems. The aim of this study was to investigate the efficacy of gabions (rock filled structures) as an ecological engineering tool by comparing community structure on these structures with pre-existing seawall structures within a small harbour and marina in South Africa (Knysna Harbour). The objectives of the study were to compare the differences in; 1) fish and; 2) colonising organisms’ diversity and composition between two artificial structures. Thirteen gabion boxes were deployed in Knysna Harbour and together with corresponding seawalls, monitored quarterly over a period of 12 months (August 2020 – August 2021) to assess taxon and functional richness, diversity, abundance and composition of fish, invertebrate and algal species. Physico-chemical characteristics of the water body were also monitored quarterly. Remote underwater video systems were used to quantify MaxN (maximum number of a fish species in the frame at any one time during each set that gives an indication of relative abundance) and identify fish species. The results of the two-way crossed ANOVAs indicated that gabion habitats recruited greater numbers and more types of fish species and from more functional groups than the seawalls, especially omnivorous and carnivorous fish. Additionally, photoquadrats were used to quantify percentage cover, counts and to identify colonising taxa. The results of the two-way crossed ANOVAs indicated that gabions hosted greater numbers of species resulting in a higher overall diversity and abundance of colonising organisms than seawalls. By contrast, the seawalls supported more types of functional groups of colonising organisms than gabions, largely due to abundances of different algal species. The results from the crossed PERMANOVAs indicated that the composition of fish and colonising organisms were vastly different from one another, and that each habitat was supporting very different functional groups. Results indicate that whilst both gabions and seawalls contain several alien species, that the ratio of native to alien species is higher in gabion habitats. Additionally, this research observed that gabion structures hosted four species listed on the IUCN Red List of Threatened Species. This study has highlighted that the use of gabions (with their natural increased complexity) could be important to consider for the future of urban coastal development in harbours such as in Knysna Harbour. Ecological engineering projects using gabions have the potential to be used in South Africa in projects that aim at increasing biodiversity in urban coastal environments. As well as increasing the settlement and abundance of habitat-forming ecosystem engineers to ensure the long-term stability of these ecosystems. They can be used both in the development of new costal development projects as well as in an ad-hoc fashion where they can be interspersed on seawalls in harbours. Additionally, gabions have the potential to be used in projects that target species of conservation concern such as the endangered Knysna Seahorse (Hippocampus capensis). It is, however, important to monitor the invasion by non-native species in future ecological engineering projects in South Africa as well as their potential for creating ecological traps (a situation in which an organism may be convinced to settle in a low-quality habitat) for certain species. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
- Full Text:
- Date Issued: 2024-04-04
A discourse analysis study of traditional health practitioners’ role in the treatment of female sexual violence and its mental health sequelae in KwaZulu-Natal
- Authors: Muthwa, Nqobile
- Date: 2024-04
- Subjects: Women -- Violence against -- South Africa , Sex discrimination against women -- South Africa , Physicians -- South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/63904 , vital:73625
- Description: South Africa is considered the epicentre of rape, leading to its reputation as the ‘rape capital of the world’. As a way of mitigating the risk of re-victimisation to individuals who have experienced rape, hospital-based post-rape centres were developed to offer services and support to rape victims. The uptake of these services remains scant as issues such as rape stigma, limited knowledge on their availability and alternative health systems limits their usage. In South Africa, there exists medical pluralism, which refers to multiple ways of making sense of illness and treatment seeking methods. It is estimated that around 80% of South Africans utilise the services of traditional health practitioners in conjunction with biomedical health practices or as a standalone service to get alternative solutions for their health needs. Victims of rape need to access a wide range of services such as post-exposure prophylaxis (PEP), medical examinations, and emergency contraception. There has been a paucity in research looking into the alternative treatments accessed by rape victims who do not access services in the formal healthcare system. It is against this backdrop that this study explored the construction and treatment formulation of rape by traditional health practitioners. The study focused on the use of language and how it becomes action that influences the services rendered to rape victims. Thematic analysis, discourse and conversational analytical approaches were used to analyse data that emerges from the one-on-one interviews. 15 traditional healers who identified as abathandazi, Izangoma and izinyanga were selected to participate in the present study. The healthworlds framework and social constructionism were used to make sense of how traditional health practitioners construct rape and how the dominant discourses surrounding rape influence how they understand their position as healthcare providers. The main findings of the study illustrated that in the healthworld of traditional healers’ understanding of rape was constructed as ukungcola nobumnyama / impurity and darkness. These discourses spoke to the perception of rape as an aberration as one’s ancestors should prevent traumas and catastrophes from befalling on the individual. When rape occurs, it signalled spiritual problems resulting into a phenomenon where ancestors cannot safeguard the living. Under these discourse rape was also constructed as something that taints, impurifies and contaminates not just the raped individual but their entire bloodline and ancestors. As a result of the discourse surrounding rape, cleansing and purification rituals played a huge role in post-rape care. In addition, traditional health practitioners viewed their role as facilitators in reestablishing the relationship between the raped individual and their ancestors. The study observed that rape victims who share the same healthworld are likely to experience spiritual transgressions following rape which will have long-lasting effects on the psychological health outcomes of victims. The present study recommends a post-rape care model that advocates for collaborative opportunities between biomedical and traditional healthcare practitioners. This model can be integrated into existing post-rape care systems to provide holistic and comprehensive healthcare that addresses biopsychosocial as well as the spiritual and cultural influences of rape. , Thesis (DPhil) -- Faculty of Health Science, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Muthwa, Nqobile
- Date: 2024-04
- Subjects: Women -- Violence against -- South Africa , Sex discrimination against women -- South Africa , Physicians -- South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/63904 , vital:73625
- Description: South Africa is considered the epicentre of rape, leading to its reputation as the ‘rape capital of the world’. As a way of mitigating the risk of re-victimisation to individuals who have experienced rape, hospital-based post-rape centres were developed to offer services and support to rape victims. The uptake of these services remains scant as issues such as rape stigma, limited knowledge on their availability and alternative health systems limits their usage. In South Africa, there exists medical pluralism, which refers to multiple ways of making sense of illness and treatment seeking methods. It is estimated that around 80% of South Africans utilise the services of traditional health practitioners in conjunction with biomedical health practices or as a standalone service to get alternative solutions for their health needs. Victims of rape need to access a wide range of services such as post-exposure prophylaxis (PEP), medical examinations, and emergency contraception. There has been a paucity in research looking into the alternative treatments accessed by rape victims who do not access services in the formal healthcare system. It is against this backdrop that this study explored the construction and treatment formulation of rape by traditional health practitioners. The study focused on the use of language and how it becomes action that influences the services rendered to rape victims. Thematic analysis, discourse and conversational analytical approaches were used to analyse data that emerges from the one-on-one interviews. 15 traditional healers who identified as abathandazi, Izangoma and izinyanga were selected to participate in the present study. The healthworlds framework and social constructionism were used to make sense of how traditional health practitioners construct rape and how the dominant discourses surrounding rape influence how they understand their position as healthcare providers. The main findings of the study illustrated that in the healthworld of traditional healers’ understanding of rape was constructed as ukungcola nobumnyama / impurity and darkness. These discourses spoke to the perception of rape as an aberration as one’s ancestors should prevent traumas and catastrophes from befalling on the individual. When rape occurs, it signalled spiritual problems resulting into a phenomenon where ancestors cannot safeguard the living. Under these discourse rape was also constructed as something that taints, impurifies and contaminates not just the raped individual but their entire bloodline and ancestors. As a result of the discourse surrounding rape, cleansing and purification rituals played a huge role in post-rape care. In addition, traditional health practitioners viewed their role as facilitators in reestablishing the relationship between the raped individual and their ancestors. The study observed that rape victims who share the same healthworld are likely to experience spiritual transgressions following rape which will have long-lasting effects on the psychological health outcomes of victims. The present study recommends a post-rape care model that advocates for collaborative opportunities between biomedical and traditional healthcare practitioners. This model can be integrated into existing post-rape care systems to provide holistic and comprehensive healthcare that addresses biopsychosocial as well as the spiritual and cultural influences of rape. , Thesis (DPhil) -- Faculty of Health Science, School of Behavioural & Lifestyle Sciences, 2024
- Full Text:
- Date Issued: 2024-04
A framework for the strategic alignment of internal auditing in the public sector
- Authors: Nyenyiso, Sizwe
- Date: 2024-04
- Subjects: Auditing, Internal , Auditing , Accounting
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/65368 , vital:74095
- Description: The role of internal auditing has evolved from a control-based function to a strategic partner of strategy formulation and execution. In today’s fast paced business environment, the demand for internal audit (IA) services has increased enormously as management struggles to respond to disruptions. To maximise the IA value and effectively respond to the expectations of stakeholders, the internal audit functions (IAFs) must be properly aligned with the strategic direction of their organisations. Public sector IAFs must align their work with the strategies, objectives and risks of the public sector organisations and promote organisational improvement. Failure to strategically align the IAFs may lead to the non-delivery of their mandate, and thus be unable to assure, advise and provide the insights that inform strategic decision making. It is concerning that the public sector IAFs may not be adequately aligned to the strategic direction of their organisations, and that no mechanism is in place to enable this alignment. Hence the primary objective of this study to develop a framework for aligning public sector IAFs with the strategic direction of the South African public sector organisations. The secondary objectives were to investigate factors that impact on IA alignment with the strategies of the public sector organisations; and how these can be integrated into the IA strategic alignment framework. This qualitative Delphi study used a combination of the Agency Theory and Strategic Alignment Theory (SAT) to better understand the phenomenon of IA strategic alignment. An iterative process of three Delphi rounds was followed to facilitate consensus among participants, who were selected using a purposive sampling method. This culminated in the development of IA strategic alignment framework, encompassing five components: organisational context; IA governance; IA planning approach; IA processes and IA resourcing, as well as 48 factors (35 positive and 13 negative) of IA strategic alignment. The study also found 15 benefits of IA strategic alignment (eight benefits to the organisation and seven to the IAF). , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Accounting, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Nyenyiso, Sizwe
- Date: 2024-04
- Subjects: Auditing, Internal , Auditing , Accounting
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/65368 , vital:74095
- Description: The role of internal auditing has evolved from a control-based function to a strategic partner of strategy formulation and execution. In today’s fast paced business environment, the demand for internal audit (IA) services has increased enormously as management struggles to respond to disruptions. To maximise the IA value and effectively respond to the expectations of stakeholders, the internal audit functions (IAFs) must be properly aligned with the strategic direction of their organisations. Public sector IAFs must align their work with the strategies, objectives and risks of the public sector organisations and promote organisational improvement. Failure to strategically align the IAFs may lead to the non-delivery of their mandate, and thus be unable to assure, advise and provide the insights that inform strategic decision making. It is concerning that the public sector IAFs may not be adequately aligned to the strategic direction of their organisations, and that no mechanism is in place to enable this alignment. Hence the primary objective of this study to develop a framework for aligning public sector IAFs with the strategic direction of the South African public sector organisations. The secondary objectives were to investigate factors that impact on IA alignment with the strategies of the public sector organisations; and how these can be integrated into the IA strategic alignment framework. This qualitative Delphi study used a combination of the Agency Theory and Strategic Alignment Theory (SAT) to better understand the phenomenon of IA strategic alignment. An iterative process of three Delphi rounds was followed to facilitate consensus among participants, who were selected using a purposive sampling method. This culminated in the development of IA strategic alignment framework, encompassing five components: organisational context; IA governance; IA planning approach; IA processes and IA resourcing, as well as 48 factors (35 positive and 13 negative) of IA strategic alignment. The study also found 15 benefits of IA strategic alignment (eight benefits to the organisation and seven to the IAF). , Thesis (PhD) -- Faculty of Business and Economic Sciences, School of Accounting, 2024
- Full Text:
- Date Issued: 2024-04
A skills development framework for the built environment
- Authors: Sibanda, Cynthia , Els, Deon
- Date: 2024-04
- Subjects: Construction industry -- Management -- Study and teaching (Higher) -- South Africa , Employees -- Training of -- South Africa , Occupational training -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64808 , vital:73916
- Description: The built environment is one of the largest sources of employment and makes a significant contribution to the gross domestic product of many countries around the world. The built environment is a significant contributor to socio-economic development in every nation irrespective of the geographical difference between countries. Therefore, it is imperative that new graduates of the built environment identify key indicators of competitiveness in order to survive and ensure their success in a constantly changing market. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop a performance framework for perceived success of skills development within the built environment. A descriptive survey was conducted among past and present Infrastructure Skills Development Grant programme graduates from the following built environment disciplines: Electrical Engineering, Construction Project Management, Architectures, Town and Regional Planners, Environmental Scientists, Chemical Scientists, Quantity Surveyors and Civil Engineering as well as past built-environment graduates of Nelson Mandela University (NMU) in South Africa. The findings of the study suggested that the following variables had a positive influence on the perceived success of skills development within the built environment: Education; Transformational Decolonisation in Education; Accelerated Advanced Training; Emotional Intelligence; Self-Empowerment Skills; Research; Corporate Governance; Transformation in the industry and Project Management. In addition, the following variables in the empirical framework were identified as having an effect on the perceived success of skills development within the built environment: Education; Transformational Decolonisation in Education; Accelerated Advanced Training; Emotional Intelligence; Self-Empowerment Skills; Research; Corporate Governance; Transformation in the industry and Project Management. , Thesis (MSc) -- Faculty of Engineering, the Built Environment, and Technology, School of Built Environment and Civil Engineering, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Sibanda, Cynthia , Els, Deon
- Date: 2024-04
- Subjects: Construction industry -- Management -- Study and teaching (Higher) -- South Africa , Employees -- Training of -- South Africa , Occupational training -- South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64808 , vital:73916
- Description: The built environment is one of the largest sources of employment and makes a significant contribution to the gross domestic product of many countries around the world. The built environment is a significant contributor to socio-economic development in every nation irrespective of the geographical difference between countries. Therefore, it is imperative that new graduates of the built environment identify key indicators of competitiveness in order to survive and ensure their success in a constantly changing market. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop a performance framework for perceived success of skills development within the built environment. A descriptive survey was conducted among past and present Infrastructure Skills Development Grant programme graduates from the following built environment disciplines: Electrical Engineering, Construction Project Management, Architectures, Town and Regional Planners, Environmental Scientists, Chemical Scientists, Quantity Surveyors and Civil Engineering as well as past built-environment graduates of Nelson Mandela University (NMU) in South Africa. The findings of the study suggested that the following variables had a positive influence on the perceived success of skills development within the built environment: Education; Transformational Decolonisation in Education; Accelerated Advanced Training; Emotional Intelligence; Self-Empowerment Skills; Research; Corporate Governance; Transformation in the industry and Project Management. In addition, the following variables in the empirical framework were identified as having an effect on the perceived success of skills development within the built environment: Education; Transformational Decolonisation in Education; Accelerated Advanced Training; Emotional Intelligence; Self-Empowerment Skills; Research; Corporate Governance; Transformation in the industry and Project Management. , Thesis (MSc) -- Faculty of Engineering, the Built Environment, and Technology, School of Built Environment and Civil Engineering, 2024
- Full Text:
- Date Issued: 2024-04
An in vitro evaluation of the anti-breast cancer activity of Nigella sativa extracts and its bioactive compound in combination with curcumin
- Authors: Botha, Susanna Gertruida
- Date: 2024-04
- Subjects: Herbs -- Therapeutic use , Radiation-protective agents , Breast -- Cancer -- Treatment
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/63639 , vital:73571
- Description: Breast cancer constitutes 23% of all cancers in South African females. Curcumin and Nigella sativa have anti-cancer, anti-metastatic and antioxidant-properties and may be effective against breast cancer. This study focused on the effect of N. sativa extracts or thymoquinone and curcumin, individually and in combination, on breast cancer cells. An MTT assay showed that curcumin reduced cell viability by 50% (IC50) at 18 ± 2.63 μg/mL and thymoquinone (TQ) at 5 ± 0.95 μg/mL against the MDA-MB-231 cells. The IC50 values for curcumin and TQ were 35 ± 6.98 μg/mL and 4 ± 0.96 μg/mL against the MCF-7 cells, respectively. The IC50 value for the NSBE was determined to be 350 ± 55 μg/mL. The IC50 value of NSAE did not fall within the selected concentration range. Synergism was noted for combinations of NSBE with curcumin, and combinations of TQ with curcumin, against both MCF-7 and MDA-MB-231 cells. Two synergistic combinations per treatment per cell line, as determined by the combination index analysis, were chosen for further investigation. The combinations and individual treatments tested against the MCF-10A cells, were not significant, except for NSBE80:CURC20 combination. Curcumin had the most significant anti-oxidant activity; however, no link was noted between the anti-oxidant activity and the cytotoxicity of the combinations. The combination treatments induced apoptosis more effectively than the individual treatments. Caspase-3 dependent apoptosis was noted for NSBE10:CURC90 and TQ80:CURC20 combinations against the MDA-MB-231 cells, and the TQ60:CURC40 combination against the MCF-7 cells. The individual and combined treatments effectively reduced MDA-MB-231 cell adhesion to fibronectin, but not all reduced the cell adhesion to laminin. Based on these results, the combinations of curcumin with TQ or NSBE, have promising anticancer benefits against breast cancer. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Botha, Susanna Gertruida
- Date: 2024-04
- Subjects: Herbs -- Therapeutic use , Radiation-protective agents , Breast -- Cancer -- Treatment
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/63639 , vital:73571
- Description: Breast cancer constitutes 23% of all cancers in South African females. Curcumin and Nigella sativa have anti-cancer, anti-metastatic and antioxidant-properties and may be effective against breast cancer. This study focused on the effect of N. sativa extracts or thymoquinone and curcumin, individually and in combination, on breast cancer cells. An MTT assay showed that curcumin reduced cell viability by 50% (IC50) at 18 ± 2.63 μg/mL and thymoquinone (TQ) at 5 ± 0.95 μg/mL against the MDA-MB-231 cells. The IC50 values for curcumin and TQ were 35 ± 6.98 μg/mL and 4 ± 0.96 μg/mL against the MCF-7 cells, respectively. The IC50 value for the NSBE was determined to be 350 ± 55 μg/mL. The IC50 value of NSAE did not fall within the selected concentration range. Synergism was noted for combinations of NSBE with curcumin, and combinations of TQ with curcumin, against both MCF-7 and MDA-MB-231 cells. Two synergistic combinations per treatment per cell line, as determined by the combination index analysis, were chosen for further investigation. The combinations and individual treatments tested against the MCF-10A cells, were not significant, except for NSBE80:CURC20 combination. Curcumin had the most significant anti-oxidant activity; however, no link was noted between the anti-oxidant activity and the cytotoxicity of the combinations. The combination treatments induced apoptosis more effectively than the individual treatments. Caspase-3 dependent apoptosis was noted for NSBE10:CURC90 and TQ80:CURC20 combinations against the MDA-MB-231 cells, and the TQ60:CURC40 combination against the MCF-7 cells. The individual and combined treatments effectively reduced MDA-MB-231 cell adhesion to fibronectin, but not all reduced the cell adhesion to laminin. Based on these results, the combinations of curcumin with TQ or NSBE, have promising anticancer benefits against breast cancer. , Thesis (MSc) -- Faculty of Science, School of Biomolecular & Chemical Sciences, 2024
- Full Text:
- Date Issued: 2024-04
Analysing the influence of banking loyalty programmes on South African consumer behaviour post-Covid
- Authors: Jordaan, Ross
- Date: 2024-04
- Subjects: Banks and banking -- South Africa , Customer loyalty programs , Customer clubs , consumer behaviour
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/65075 , vital:74016
- Description: Banking institutions promote loyalty programmes that offer customers cost saving benefits. The research investigates the perceived loyalty programme benefits from a customer perspective. The research analyses the customer satisfaction and the effect the banking loyalty programmes has on customer behaviour post Covid-19. Focusing on customer retention and customer relationship management, banking institutions have adopted loyalty programmes as a strategic tool to enhance customer loyalty and satisfaction. The findings of this research provided valuable insights into the key factors that drives customer loyalty and engagement with banking loyalty programmes. This study used quantitative research methodology utilizing surveys and statistical analyses to gather and interpret data using simple random sampling from a diverse sample of banking customers from the Gqeberha area. A response rate of 50.5% was achieved in this study. The findings of this study underscore a pivotal realisation that banking loyalty programmes in isolation prove insufficient to exert a significant influence on banking customer behaviour in the post-Covid era. A contemporary approach is required to meet the evolving expectations and dynamics within the customer base. The study observed that digital transformation and strategic partnerships are a key determinant in shaping banking customer behaviour, hence the study advocates for a synergised approach, where banking loyalty programmes, digital transformation, and strategic partnerships operate in tandem. It is recommended that banks should understand the dynamics of consumer behaviour in the context of loyalty programmes, hence they can optimize their strategies to strengthen their position and relationships with their customers. Traditional silos of banking loyalty programmes must integrate and adapt to the current banking customer preferences, this holistic approach is not just a recommendation but also imperative for sustainable growth and resilience in the banking sector. The study will contribute to academic research and offer practical implications for banking executive seeking to build, design and implement effective loyalty programmes in a highly competitive banking industry. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-04
Analysing the influence of banking loyalty programmes on South African consumer behaviour post-Covid
- Authors: Jordaan, Ross
- Date: 2024-04
- Subjects: Banks and banking -- South Africa , Customer loyalty programs , Customer clubs , consumer behaviour
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/65075 , vital:74016
- Description: Banking institutions promote loyalty programmes that offer customers cost saving benefits. The research investigates the perceived loyalty programme benefits from a customer perspective. The research analyses the customer satisfaction and the effect the banking loyalty programmes has on customer behaviour post Covid-19. Focusing on customer retention and customer relationship management, banking institutions have adopted loyalty programmes as a strategic tool to enhance customer loyalty and satisfaction. The findings of this research provided valuable insights into the key factors that drives customer loyalty and engagement with banking loyalty programmes. This study used quantitative research methodology utilizing surveys and statistical analyses to gather and interpret data using simple random sampling from a diverse sample of banking customers from the Gqeberha area. A response rate of 50.5% was achieved in this study. The findings of this study underscore a pivotal realisation that banking loyalty programmes in isolation prove insufficient to exert a significant influence on banking customer behaviour in the post-Covid era. A contemporary approach is required to meet the evolving expectations and dynamics within the customer base. The study observed that digital transformation and strategic partnerships are a key determinant in shaping banking customer behaviour, hence the study advocates for a synergised approach, where banking loyalty programmes, digital transformation, and strategic partnerships operate in tandem. It is recommended that banks should understand the dynamics of consumer behaviour in the context of loyalty programmes, hence they can optimize their strategies to strengthen their position and relationships with their customers. Traditional silos of banking loyalty programmes must integrate and adapt to the current banking customer preferences, this holistic approach is not just a recommendation but also imperative for sustainable growth and resilience in the banking sector. The study will contribute to academic research and offer practical implications for banking executive seeking to build, design and implement effective loyalty programmes in a highly competitive banking industry. , Thesis (MBA) -- Faculty of Business and Economic Sciences, Business School, 2024
- Full Text:
- Date Issued: 2024-04
Balancing an educator’s right to strike and a child’s right to basic education.
- Authors: Maluleke, Mongwena John
- Date: 2024-04
- Subjects: Educational law and legislation , Children's right to education , Basic education
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/66128 , vital:74400
- Description: This thesis examines how a fair balance can be realised between the educator’s right to strike and the child’s right to education. International and constitutional frameworks are analysed to uncover South Africa’s position on the two opposing rights and the various balancing approaches available. The study recommends a consensus-based approach to balance the rights of educators with that of the child’s right to education. It further proposes the establishment of a structured and organised forum or institution with the sole purpose of dealing with the rights of educators that compete with the rights of learners. , Thesis (LLD) -- Faculty of Law, Department of Mercantile law, 2024
- Full Text:
- Date Issued: 2024-04
- Authors: Maluleke, Mongwena John
- Date: 2024-04
- Subjects: Educational law and legislation , Children's right to education , Basic education
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/66128 , vital:74400
- Description: This thesis examines how a fair balance can be realised between the educator’s right to strike and the child’s right to education. International and constitutional frameworks are analysed to uncover South Africa’s position on the two opposing rights and the various balancing approaches available. The study recommends a consensus-based approach to balance the rights of educators with that of the child’s right to education. It further proposes the establishment of a structured and organised forum or institution with the sole purpose of dealing with the rights of educators that compete with the rights of learners. , Thesis (LLD) -- Faculty of Law, Department of Mercantile law, 2024
- Full Text:
- Date Issued: 2024-04