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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
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Developing biological control agents for the management of the invasive tree Robinia pseudoacacia

  • Authors: Wolmarans, Abigail
  • Date: 2024-04-05
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/435717 , vital:73181 , DOI 10.21504/10962/435717
  • Description: Robinia pseudoacacia (Fabaceae) is a deciduous tree native to the Appalachian Mountains of North America but has become naturalised and invasive in other countries such as temperate North America, Europe, Australia, and Southern Africa. In South Africa the tree is classified as a category 1B invasive alien under the National Environmental Management Act (NEMBA), which stipulates the species requires some form of control as it has already caused extensive negative ecological and economic impacts. In the invaded range the tree creates monocultures that displace native species and spreads rapidly from suckering roots, making it a proficient invader. The South Africa plant prioritisation system suggests R. pseudoacacia is in the top three species which should be considered for classical weed biological control in South Africa. This thesis investigates which insects known to be associated with tree should be prioritised as candidate agents, as well as offering interesting insights into prioritising insects for weed biological control and using plant phylogenies and available literature to predict insect specificity. To ensure that no candidate biological control agents were already present in South Africa as well as to prioritise which guilds of the tree to prioritise for potential biological control, pre-release surveys were conducted across nine sites where the tree has invaded South Africa. It was found that no insects from the native range of R. pseudoacacia were present in South Africa. Seed surveys revealed that generalist insects attack a sizable proportion (68 %) of the seeds on the trees. In combination with a low seed soil bank (15.8 %) this suggests that seed- feeding agents may be helpful, however, candidate agents which damage leaves should be prioritised due to R. pseudoacacia relying heavily upon vegetative reproduction and much less on sexual reproduction. Leaves may therefor reduce the spread of these invasive trees. The insect assemblages in the native range of R. pseudoacacia are well understood. In addition, several associated insects have unintentionally followed the tree on its global spread, where they are often regarded as pests. The third chapter is therefore aimed at prioritising the known insects associated with the tree in both the native and invaded range. Literature surveys and Harris (1973) prioritisation systems were used to prioritise close to 64 candidate biological control agents down to three foliage- feeding agents, namely Odontota dorsalis (Coleoptera, Chrysomelidae), Macrosaccus robiniella (Lepidoptera, Gracillariidae) and Obolodiplosis robiniae (Diptera, Cecidomyiidae). To further prioritise the six selected agents in Chapter 4, species distribution were modelled with known climatic variables. This was done by using the species known occurrence localities, from both the native and where applicable invaded ranges, to identify which species that would best match with South Africa’s climate. The study showed that O. dorsalis is best suited to survive in South Africa, followed by O. robiniae and then M. robiniella. Collected data aided in the introduction of the prioritised O. robiniae into South African quarantine facilities. Unfortunately, despite several attempts, cultures could not be established, making conventional host specificity testing impossible. Thus, in Chapter 5 we aimed to determine the potential host range of the midge using information from experts in the field of galling insects, literature surveys, agricultural pest lists, and social science platforms coupled with native and invaded range surveys. The list of non-target species to consider as potential hosts was refined by developing phylogenetic trees of closely related Fabaceae that share the same distribution (native and invaded) as R. pseudoacacia. Through the available information gathered, and field surveys of these species, O. robiniae has not been shown to utilise any species, other than those from the Robinoid clade. In addition, the midge has also never been recorded on a number of closely related leguminous fodder and horticultural species growing in close proximity at high densities to R. pseudoacacia - suggesting negligible risk to South African growers of the same species. Host-specificity assessments through field surveys can be regarded as one of the best indicators of the ecological host range, however, this information is difficult to quantify and infrequently available, thus seldom used when determining the safety of a candidate biocontrol agent. In this unique study, using the extensive data collected we are able to show that O. robiniae would be potentially safe for release in South Africa. However, open field tests exposing closely related non-target plant species under natural and semi-natural conditions are planned in Switzerland over the next two years aiming to confirm these conclusions. By identifying and prioritizing potential biological control agents, this research contributes to the development of a targeted and sustainable solution for managing R. pseudoacacia in South Africa. The economic implications of successful biological control include reduced costs associated with invasive species management and ecosystem restoration. Additionally, by mitigating the negative ecological impacts, the agricultural systems in affected regions stand to benefit from enhanced resilience and productivity. Furthermore, the study's approach of using plant phylogenies and available literature to predict insect specificity offers a valuable methodological contribution to the broader field of weed biological control. This methodology can be adapted and applied to other invasive species, providing a framework for efficient and informed decision-making in weed management strategies. In essence, this research not only addresses the specific challenges posed by R. pseudoacacia in South Africa but also provides a template for tackling similar issues in different geographical contexts, thereby contributing to global efforts in sustainable agriculture and environmental conservation. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
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Genetic connectivity of the slinger Chrysoblephus puniceus among Marine Protected Areas and unprotected areas along the east coast of South Africa

  • Authors: Ockhuis, Samantha Angelique Natasha
  • Date: 2024-04-05
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/435954 , vital:73215 , DOI 10.21504/10962/435954
  • Description: Marine Protected Areas (MPAs) are advocated worldwide for the conservation of biodiversity and fisheries management, as well as for adaptation and resilience in the face of climate change. Their effectiveness has been noted through increases in abundances, biomass, sizes and diversity of species, as well as the recovery of overexploited fisheries. For MPAs to realise their full potential, these benefits need to expand beyond their boundaries through larval dispersal and/or adult spillover. Connectivity between MPAs is critical for planning and placement of MPAs, as this promotes the persistence of metapopulations, their recovery from disturbance, as well as productivity in marine ecosystems. The effectiveness of MPAs in conserving biodiversity along the east coast of South Africa has been established; however, limited evidence is available on whether they offer benefits beyond their boundaries, enhancing biodiversity and fisheries in adjacent areas. The slinger Chrysoblephus puniceus, an endemic southern African sparid, is a major component of the commercial linefishery in KwaZulu-Natal (KZN), South Africa and southern Mozambique, and is also caught in the recreational ski-boat fishery in these regions. The spawning of slinger occurs in shoals on offshore reefs from southern Mozambique to the north of KZN, and larvae are likely transported southwards, assisted by the southward-flowing Agulhas Current and promoted by a relatively long larval duration. Slinger are relatively resident, but occasional northward migrations have been observed. These life history characteristics suggested that slinger would be a suitable biological model to test connectivity along the east coast, and particularly connectivity between MPAs. The aim of this study was therefore to investigate connectivity of slinger between MPAs and the surrounding areas along the east coast of South Africa, using restriction-site-associated DNA (RAD) sequencing. This formed part of the larger CAPTOR project investigating east coast MPA connectivity across a range of taxa and habitat types. A temporal comparison of genetic diversity in slinger spanning two sampling events (2012 and 2018) revealed no substantial changes in genetic diversity, as well as a lack of genetic structure along the KZN coast. Similarly, no substantial changes in effective population size (Ne) were found between 2012 and 2018 for microsatellites and Single Nucleotide Polymorphisms (SNPs). However, subtle, albeit non-significant, differences were observed both spatially and over time in the microsatellite data, indicating some instability along the KZN coast. A lack of genetic structure based on RAD sequencing was observed between east coast MPAs and the surrounding areas. This implies high connectivity along the coast - not only are east coast MPAs connected, the surrounding areas are also connected, and there is replenishment between all areas via larval dispersal and/or adult spillover. Analyses of multidirectional gene flow between MPAs, together with known spatial spawning patterns and prior particle dispersal modelling, identified the Richards Bay area as a key source of recruits. However, parentage analysis – a direct method to estimate connectivity – failed to match any parent-offspring pairs in this study; successful parentage assignments are highly dependent on intensive sampling of potential parents and are seldom feasible in marine systems, as most populations have large effective population sizes. Estimates of intergenerational effective population size for slinger in this study are considered large - >2 000 and infinite based on adults and juveniles, respectively. Population genetics revealed close genetic similarities between slinger adult and juvenile slinger sites, emphasizing genetic connectivity and the lack of structure between sites observed before. This was the first study on South African sparids to use RAD sequencing to assess genetic connectivity between MPAs along the east coast of South Africa. Overall, results provide evidence that MPAs along the east coast of South Africa are connected, and can readily replenish or be replenished by other sites along the east coast of South Africa, whether they are within MPAs or not. So too are the areas surrounding MPAs interconnected, and slinger forms a homogenous single population on the east coast of South Africa. This notwithstanding, it is important that east coast MPAs, particularly those that host spawning shoals of slinger, are well managed in order that they continue to provide recruits to sustain the population and support sustainable fisheries. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
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Implications of Lantana camara invasion on rural livelihoods and native woody species in the Kavango Zambezi Transfrontier Conservation Area, Zimbabwe

  • Authors: Francis, Buhle
  • Date: 2024-04-05
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/435896 , vital:73210 , DOI 10.21504/10962/435896
  • Description: Lantana (Lantana camara Linn, Verbenaceae) is an invasive alien species found in many disturbed and conservation habitats worldwide. Much work has been conducted on the impacts that L. camara has on ecosystems and communities living in affected areas. In some localities, interventions to eradicate L. camara have been made to reduce the impacts, with follow-up assessments on the benefits of these restoration efforts at some locations. However, L. camara continues to spread globally, and the Zambezi Transfrontier Conservation Area (KAZA TFCA) in Zimbabwe has not been spared. The KAZA TFCA is an important area for biodiversity conservation, ecotourism, and enabling and encouraging regional peace, cooperation and socio-economic advancement. This study was carried out in the KAZA TFCA, covering the Hwange District in Zimbabwe, with the primary aim to ascertain the effects of L. camara on rural livelihoods, native woody species and the soil properties of KAZA TFCA, and whether the policy environment and passive restoration efforts have been effective in controlling it in the area. The study employed a mixed-methods approach using both qualitative and quantitative methodologies to resolve the research problem. Firstly, 102 plots were randomly established in the study areas where native woody species were recorded. In the first section of the Communal area, there were 60 plots in total comprising of 34 invaded and 8 uninvaded. In the other section of the Communal area, 21 plots were sampled, with 7 invaded, 7 control and the other 7 cleared. In the Victoria Falls National Park, 18 plots were established which comprised of 12 invaded and 6 uninvaded. In the Victoria Falls Rainforest area, 21 plots were established which comprised of 7 invaded, 7 cleared and 7 control. The criteria of selecting 102 plots was based on a number of factors which included; Research objectives, Randomisation, Historical data (From locals and Environmental Management Agency), Environmental variables, Spatial distribution if invasion, Accessibility, Budget and Time constraints. A total of 72 soil samples were collected for laboratory analysis of nitrogen, pH, organic carbon, phosphorous and potassium. The 72 soil samples were considered based on available funding for analysis. This soil samples collected samples were representative of the entire study site. In the Communal areas, 300 household questionnaires (representing approximately 12.35% of the total number of 2 430 households) were administered, two focus groups with elderly residents were conducted, and 11 key informant interviews were held. One-way ANOVAs and several multivariate tests were conducted to assess the impact of L. camara invasion on native woody species composition and soil properties. Descriptive statistics were used to conduct a cost-benefit analysis of the presence of L. camara in the study sites. This was coupled with a principal component analysis to assess vulnerability of respondents to invasion, based on variables such as age, gender and level of education. One-way ANOVAs and multivariate analysis were also used to assess if passive restoration contributed to the recovery of native woody vegetation and the improvement of soil properties. In invaded plots, restoration natural recovery occurred after removing the L. camara invasion with no further intervention done after the removal. Document and thematic analyses were conducted to evaluate perceptions and knowledge of policy and legislation pertaining to L. camara management. Lantana camara negatively affected the native woody species, as evidenced by a reduction in species richness, abundance, density, height and canopy cover. Lantana camara also altered soil properties such as texture, chemical composition, colour and porosity, as found by comparing invaded and non-invaded plots in both the Park and Communal areas. Once L. camara invades an area it tends to become dominant at the expense of native species, many of which are a source of livelihood for the local people. Thus, displacement of native species by L. camara potentially increases the vulnerability of local people, some of whom are already experiencing challenges, such as drought and human-wildlife conflict. The invasion of L. camara was found to date back over eight decades ago. Based on focus group discussions with elderly participants, the initial invasion of L. camara in the Ndlovu Communal area was approximated to 1942. This invasion was noted to have begun in ward 2 of Ndlovu Communal area and spread to the other four wards in the study area over 16 years. Despite the challenges of losses and costs induced by the invasion of L. camara, benefits and gains were reported in some areas. For example, in the protected areas, the fruits of L. camara are eaten by birds, while bees use the flowers for honey production. It is noted that L. camara seeds spread through bird droppings become a cost to the environment through further proliferation of the invasion. In some communal areas, households use L. camara for hedges, herbal medicine, cane for furniture, and as an ornament. The relative losses and gains associated with L. camara are context-specific and are dependent on several factors. In this study, the presence of L. camara resulted in negative impacts that included the reduced area of productive land for crops and grazing. Combined, the mean costs borne were US$ 483 household-1 year-1. Furthermore, the combined mean benefits of L. camara, such as use as live fencing around homesteads and fields, mosquito repellent, fruit, fire kindling and ornaments, protection of fowls from raptors, and the prevention of gully erosion along watercourses, were valued at US$ 716 household-1 year-1, thereby exceeding the costs by 48%. However, most (62%) households experienced a net negative cost-benefit ratio. The overall mean value across the sample indicates benefits outweigh costs because a minority of households experience large net benefits. Although L. camara is invasive in the area, communities have taken advantage of its presence to find uses that contribute to their day-to-day lives. Despite the use of L. camara by communities, efforts to remove it have been made in some parts of the Ndlovu Communal area as well as in the Parks (Victoria Falls and Rainforest). The study investigated the impact of passive restoration on native woody species and soil properties. The findings showed a significant improvement in species richness and diversity in cleared plots compared with invaded plots. The species composition differed in the cleared, invaded and uninvaded plots with specific species favouring the different types of “treatments”. This showed the relationship between invasion and associated species. Soil properties had visible differences due to passive restoration, with figures of cleared sites consistently being intermediates of invaded and uninvaded plots. Despite the passive restoration projects, an analysis of knowledge and management showed that most local respondents whose age ranged between 25- 93 years, did not consider L. camara to be invasive but viewed it as part of the vegetation in the area. They also took little responsibility for its management. A further analysis of documents and policies related to the management of invasive alien species found that there were legal instruments in place for the management of invasive alien plants in Zimbabwe, including L. camara. The key informant interviews and the questionnaire surveys showed conflicting views on perceptions and opinions about whose responsibility it was to manage L. camara, with communities saying it is the authority’s responsibility, while some of the authorities suggested that it was everyone’s responsibility. However, some of the key informants highlighted the need to review the policies, guided by empirical studies on of the impacts of L. camara. Currently, it appears the policies are adopted from international bodies as a means of alignment to global policies, but they are not contextualised to suit the dynamics in the country. Overall, the study showed that the presence of L. camara in the KAZA TFCA has notable negative impacts on the native woody vegetation, as well as on local livelihoods, but some households have adapted to using L. camara to benefit them. This, however, has implications for efforts to stop the spread of L. camara if its presence is considered a benefit by some and a cost by others. The efforts to remove L. camara show that the native woody vegetation recovered. The study showed the need to raise awareness of the invasive nature of L. camara because some respondents did not consider it invasive. Findings from this study have implications for the management of L. camara in KAZA TFCA and similar areas, and inferences can be made to assist in the management of other invasive alien plants. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2024
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Plankton and macroinvertebrate dynamics in the Khakhea–Bray transboundary aquifer region

  • 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
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The impacts of bottom-up and top-down drivers in shaping the herbivore community in Pafuri, Kruger National Park, South Africa

  • Authors: Walker, Gareth Alexander
  • Date: 2024-04-05
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/435703 , vital:73180 , DOI 10.21504/10962/435703
  • Description: Globally, terrestrial mammal populations are facing critical population declines and range contractions owing to habitat fragmentation and destruction, wildlife overexploitation, and climate change driven by expansion of the human population. Mammalian herbivores are integral for maintaining ecosystem structure and functionality. They do this this through herbivory, by acting as prey and cycling soil nutrients. The impacts of herbivores on ecosystems, however, vary with their spatial occupancy which is influenced by interacting bottom-up and top-down factors. Modelling the drivers of herbivore communities is no trivial task given the myriad of potential bottom-up and top-down factors, and the interactions between the two, as well as the species-specific variations in intrinsic functional traits (e.g., foraging strategy, body size, metabolic rate, etc.) influencing herbivore responses (e.g., social structure, space-use, activity patterns, etc.) to these drivers. Consequently, few studies have attempted to model both bottom-up and top-down drivers in structuring herbivore communities, particularly in an African context where predator-prey guilds include multiple species, exposed to high levels of human activity. Therefore, the overarching aim of my research was to quantify the relative effects of both bottom-up and top-down factors driving the herbivore community in the northern Pafuri region of Kruger National Park, South Africa. I utilized a combination of field (i.e., camera trap and vegetation surveys) and analytical (i.e., stable carbon isotopes from faeces and plants) techniques in conjunction with geospatial data to evaluate the impacts of bottom-up (i.e., forage quantity, quality, and water availability) and top-down (i.e., predation and anthropogenic risks) factors on herbivore spatial occupancy and activity patterns. Herbivore responses to bottom-up and top-down factors were species-specific, even among members of the same feeding guild. Specifically, I found that herbivores (varying in body size and foraging strategy) displayed temporal, spatial and in some instances, dietary shifts that reflect species-specific, ecological trade-offs between resource acquisition, and predator and human avoidance. For example, kudu (Tragelaphus strepsiceros) displayed temporal and spatial avoidance of predators and humans, and exhibited previously undocumented levels of seasonal dietary shifts which suggests that the species traded forage acquisition for reduced predation and anthropogenic risks. Further, high levels of human activity appeared to eclipse the risks associated with natural predators resulting in human induced landscapes of fear. For example, warthogs (Phacochoerus africanus) and zebra (Equus quagga) occupied habitats with higher predation risks, but displayed spatial avoidance of nature reserve boundaries which were synonymous with high levels of bushmeat poaching. Most studies focussing on the impacts of bottom-up and top-down drivers neglect to consider the roles that humans play in structuring ecological communities. The results of my thesis, however, emphasize the importance of including anthropogenic drivers when investigating the roles that various bottom-up and top-down factors play in shaping ecological communities. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
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A systematic literature review of the current approaches to dream work: global and local trends

  • Authors: Feris, Eric-John Ricardo
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/435440 , vital:73157
  • Description: Dreaming is an inherent and universal aspect of human existence that offers a profound window into the realms of consciousness and cognition. It has captivated the human imagination for centuries, prompting various methods and theories to decipher its significance. Global research underscores the enduring importance of dreams in psychotherapy, expressed through diverse methodologies, techniques, and theoretical models. Curiously, within the South African context, a cultural landscape rich in traditional healing, there exists a noticeable lack of research concerning the utilisation of dreams in therapy. This systematic literature dove into 30 articles which remained after applying the systematic literature review strict inclusion and exclusion criteria of the literature searches. From these articles, the review delved into the multifaceted world of dream work, investigated prevailing approaches and themes both on a global scale and within the South African context, and addressed three key research questions: (1) What themes can be identified from a review of current approaches to dream work globally? (2) What themes can be identified from a review of current approaches to dream work locally? (3) What are the practical implications for working with dreams according to global and local themes? A thematic analysis of the literature identified three overarching themes: (1) Psychological approaches to dream work, (2) Psychiatric and medical approaches to dream work, and (3) Socio-cultural approaches to dreams. These findings highlight the necessity of recognising cultural nuances and, underscores the importance of developing a flexible, culturally sensitive framework for dream work, and advocates for the adaptation of global dream work methodologies into culturally specific approaches, fostering psychotherapeutic benefits tailored to the South African context. The research serves as a stepping stone to further investigation into the techniques and approaches of dream work in South Africa, ultimately contributing to the broader field of dream analysis. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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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
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English morphological awareness and reading comprehension in deaf and hearing grade 3 to 7 learners from Lesotho

  • Authors: Tšehla, Puleng Magret
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/${Handle} , vital:73169
  • Description: There is a noticeable literacy crisis observed in both Deaf and hearing learners from Lesotho. This study investigates the English Morphological Awareness and reading comprehension of 26 Deaf and 82 hearing learners enrolled in grades 3 to 7 in two schools in Lesotho. This study employs a correlational cross-sectional quantitative design. Each participant completed two literacy assessment tasks: a reading comprehension task and a Morphological Awareness task. The Morphological Awareness task encompassed five subtasks that assessed the learners’ inflectional, derivational, and compound awareness. The results of these assessments are analysed through appropriate statistical analyses. In addition, errors made by the Deaf and hearing learners on the literacy assessments are compared and analysed. This analysis determines the types of errors made by each group and identifies the factors that influence these errors. The performance of both groups in terms of task scores, in general, was low. Deaf learners and hearing learners’ performance on the tasks was similar. This outcome contradicts most previous studies, which indicate that Deaf learners typically exhibit lower levels of Morphological Awareness development and reading comprehension compared to their hearing counterparts. The results of this study also suggest that there is a statistically significant relationship between Morphological Awareness and reading comprehension in both groups. Finally, Deaf and hearing learners made similar errors on the tasks. There was some evidence of influence from both the Deaf and hearing learners’ first languages (Sesotho and Lesotho Sign Language, respectively). The study demonstrates the need for more explicit morphological instruction to improve both Deaf and hearing learners’ literacy. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2024
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Functional significance of mixed-species groups for zebra (Equus quagga) in savanna habitats

  • Authors: Corry-Roberts, Carys Alexandra
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • 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
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High-altitude temporary systems and macroinvertebrate composition in La Nina cycle, Maloti-Drakensberg

  • Authors: Moyo, Sibusisiwe
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/434963 , vital:73119
  • Description: The Maloti-Drakensberg Mountain is an important water catchment area for South Africa and Lesotho. It is rich in biodiversity in terms of endemic flora and fauna and has a high density of temporary wetlands in the form of Afromontane tarns and rock pools. There is, however, limited information on the distribution of macroinvertebrates in these ecosystems and environmental factors that drives their composition. To that end, this study investigated macroinvertebrate diversity and the effect of environmental factors on community assemblage in the Maloti-Drakensberg Mountain temporary wetlands, specifically tarns and rock pools. The main aims were to describe the abundance, diversity, and distribution of macroinvertebrates in temporary wetlands in the Maloti-Drakensberg Mountain. Furthermore, it aimed to investigate the effect of environmental variables on habitat structuring, spatial variations, and macroinvertebrate community composition in tarns and rockpools in the Maloti-Drakensberg Mountain. Seventy temporary wetlands (29 tarns and 41 rock pools) were surveyed over a once-off sampling (3 March – 7 April 2022). The wetlands were from 3 provinces including Eastern Cape, Free State, and KwaZulu-Natal. 15278 individual macroinvertebrates from 13 orders, 35 families, and 46 genera were collected and identified. Species accumulation curves incorporating both tarns and rock pools showed that observed results were significantly lower than Chao 1 and Chao 2 estimates meaning that the sampled sites were not enough to provide a comprehensive picture of the biodiversity in the region. This was also observed for rock pools when the temporary wetlands were analysed separately, however, the Chao 1 and Chao 2 values for tarns were almost equal to the observed values implying that sampled sites were enough to give a detailed picture of macroinvertebrate composition in tarns. Tarns and rock pools were significantly different in terms of species richness and Shannon-Wiener diversity index but showed no significant differences for relative abundance and Pielou’s evenness. Of the 35 families identified, 19 were considered core taxa with Dytiscidae and Corixidae being the most dominant. Additionally, there was moderate Nestedness metric based on Overlap and Decreasing Fill (NODF) value of 33.05369, with 32 out of 35 families being idiosyncratic. Predators were the dominant feeding group with omnivores being the least common. Non-Metric multi-Dimensional Scaling (NMDS) and PERMANOVA results showed that tarns and rock pools supported distinctly different macroinvertebrate communities per wetland type and location respectively. Physicochemically, tarns and rock pools were significantly different in terms of water temperature, depth, area, and chlorophyll-a concentration with tarns exhibiting higher values. Temporary wetlands in the sampled localities differed in terms of pH, EC, DO, water temperature, altitude, and phosphate. Principal Component Analysis showed that tarns were positively associated with area and depth whereas rock pools with phosphate. Akaike’s Information Criterion (AICc) selection showed that area, pH, and water temperature were significantly influencing community assemblage in temporary wetlands. Furthermore, area significantly influenced all four measured biodiversity indices: relative abundance, species richness, Pielou’s evenness and Shannon-Wiener Index, with water temperature also influencing relative abundance and altitude, species richness. Overall, the species composition showed that the sites were sampled later in the hydroperiod as evidenced by the dominance of active dispersers. The extended distribution of Prosthetops gladiator in the Eastern Cape highlights the need for extensive surveys to provide valuable insight into the distribution patterns of macroinvertebrates in the region. Furthermore, the interplay between physicochemical variables and biodiversity indices emphasized area, water temperature and pH as significant factors. However, their limited explanatory power suggests that obscure factors also influence the diversity cementing the need for further exploration of these enigmatic systems. Taxonomic challenges, especially regarding large branchiopods, hindered precise species distribution and conservation status determination. This study is the first to provide a comprehensive list of macroinvertebrates from temporary wetlands in the Maloti-Drakensberg Mountain. These results establish a valuable baseline for future biological monitoring studies, particularly in assessing species composition and responses to anthropogenic activities. It is a timeous study considering the sensitivity of these systems to climate change as they act as sentinel sites hence the need for foundational data on which to make future projections. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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Home is in the wandering

  • Authors: Purdon, Bradley Michael
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/435547 , vital:73167
  • Description: Submitted in partial fulfilment of the requirements for the degree of Master of Arts in Creative Writing , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
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Investigating playing-related musculoskeletal disorders in South African instrumental musicians

  • Authors: Green, Erryn Mae
  • Date: 2024-04-04
  • Subjects: Musculoskeletal disorder , Musculoskeletal system Diseases , Musicians Wounds and injuries , Musicians Health and hygiene , Human engineering South Africa , Musicians Health risk assessment , Biomechanics , Musical instruments , Music genre
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/435310 , vital:73146
  • Description: This study, one of the first studies in SA to investigate PRMD in a wideranging sample of instrumental musicians using a validated self-report tool, shows that PRMDs are highly prevalent among a range of SA musicians and have a considerably negative effect on musicians’ performance ability and quality of life. However, making inferences about most affected genre or instrumental group was challenging due to the small sample sizes in some categories. The results from this study confirm that the nature of PRMD development is indeed multi-factorial, with factors numerous individual and playing-related factors playing a role in the development of PRMDs in SA musicians. Better support and education on health promotion for musicians, including awareness of and prevention strategies for PRMDs in the SA context are needed which may reduce the prevalence of PRMDs. , Thesis (MSc) -- Faculty of Science, Human Kinetics and Ergonomics, 2024
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It's all in your head

  • Authors: Namukuta, Sonia Charity Sajjabi
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/435536 , vital:73166
  • Description: My thesis is a collection of short stories that delve into the multifaceted nature of death, with a specific emphasis on murder, violence, death and their profound aftermath, including themes of loss, grief, and trauma. These stories offer diverse perspectives, narrated by perpetrators, voiceless victims, and those left to pick up the shattered pieces. Additionally, some stories are seen through the eyes of those tasked with handling the bodies. Often set in unnamed locations, they delve into imaginary and fantastical worlds, while remaining grounded in recognisable situations and spaces. I draw inspiration from popular and genre fiction such as horror, crime fiction and true crime stories, but approach my writing from a psychological lens, employing stylistic experimentation to challenge readers' expectations. The power of silence is a recurring motif. Rather than focusing on unearthing facts or revealing the "truth" like crime fiction often does, my narratives delve into what isn't or at times cannot be told — the unsayable. Some of my stories explore silence inherent in violence, grief, and the inability to articulate one's experience in the face of a violent act or a life prematurely ended. Others delve into the silence of untold stories and the dark secrets of the perpetrators. By exploring these contrasting perspectives, I aim to offer a nuanced exploration of death and its aftermath. The writing styles of Stephen Graham Jones, Lydia Davis, and Kuzhali Manickavel influence my work. Lydia Davis, known for her mastery of very short, flash fiction, ranging from single sentences to a paragraph or two, inspires me with her precise observations of the human condition. Her minimalist prose, carefully selecting and arranging words and sentences, encapsulates the power of less-is-more storytelling. Manickavel creates surreal yet tangible worlds, combining idiosyncratic, intense and eerie elements with unfiltered expression. Drawing from her ability to blur the lines between the surreal and the real, I infuse my stories with a sense of disquieting authenticity. Stephen Graham Jones stands out for his ability to explore morbid themes in a compelling and unconventional manner. His experimentation with horror fiction tropes, the visceral realism of his prose, and his complex characters inspire me to capture the unsettling feeling that something dreadful has occurred without explicitly detailing the facts and intricacies. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2024
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The effect of Gracilaria gracilis (Rhodophyta) on growth and behaviour of farmed abalone Haliotis midae when included in the abalone diet

  • 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
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“COVID-19 made me a single parent”: an interpretative phenomenological analysis of a woman’s perinatal experiences during the COVID-19 pandemic

  • Authors: Hadebe, Asanda Locresia
  • Date: 2024-04-04
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/435437 , vital:73158
  • Description: The COVID-19 pandemic resulted in unprecedented challenges across various aspects of life. In particular, pregnant women encountered unique challenges and circumstances that necessitated adaptation to the experience of the perinatal period1 Satyanarayana et al., (2011). A considerable amount of research has been conducted regarding women's experience of the perinatal period during COVID-19, especially in first world countries. However, inadequate research has been done in the South African context and specifically, there is a lack of qualitative research providing thick descriptions of experience. The analysis describes three master themes supported by subordinate themes. The main themes are (1) A sense of loss and change, (2) Managing COVID-19 and its regulations during the perinatal period, and (3) Glimmers of hope and desirable aftermaths. The study’s findings expand and support the growing literature of women’s experiences on the perinatal period during the COVID-19 pandemic. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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A critical analysis of the factors influencing knowledge sharing in Indian family owned businesses in South Africa

  • Authors: Sha, Shafeek
  • Date: 2024-04-03
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/434817 , vital:73107 , DOI 10.21504/10962/434817
  • Description: It is commonly believed that family businesses have formed the backbone of many economies around the globe and that they have been the predominant form of enterprise that has given rise to some of the most famous multinational enterprises. Family businesses contribute to the wealth creation in most economies and conservative estimates suggest that 65% to 80% of all businesses worldwide are owned and managed by families. In South Africa, Indian family owned businesses contribute more to employment than any other family business. There is a general perception amongst South Africans that Indian family owned businesses are more successful and that this success is continued from one generation to the next. Intrigued by this “phenomenon” for many years, the researcher decided to investigate it. The perspective adopted for this research was to look at the research problem from a knowledge management discipline viewpoint, in general, with a specific focus on knowledge sharing and Indian family owned businesses. The purpose of this study is to critically analyse the factors that influence the effectiveness of knowledge sharing in Indian family owned businesses. So the research answered the question: How do Indian family owned businesses in South Africa share their knowledge to ensure the continued success of their businesses through succeeding generations? A positivist research paradigm and philosophy was adopted for this research together with a quantitative research approach using survey research as the research strategy of choice. After conducting an extensive literature review, the next step was to develop and formulate a theoretical model, and flowing from the model and prior research, a research instrument was developed and administered to a qualifying sample of Indian family owned businesses in South Africa. Structural equation modelling was used as the principal mode of statistical analysis to measure the relationships amongst the variables in the model proposed in this study. After analysing the empirical data, the following key factors were identified as statistically significant in being determinants of knowledge sharing in Indian family owned businesses in South Africa: organisational culture, learning organisation, and leadership. These findings serve to contribute to the existing literature within the fields of knowledge management and family business. This study will richly contribute to research-based evidence of the factors that influence knowledge sharing in Indian family owned businesses. The outcomes will allow existing and emerging family businesses to ensure the future success of their enterprises from one generation to the next by embracing the empirical findings of this research and thus ultimately contribute to the future success of the family business as a whole. , Thesis (PhD) -- Faculty of Commerce, Management, 2024
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Dictionaries as pedagogic tools: a case study of selected schools in Makhanda, Eastern Cape

  • Authors: Wababa, Zola Richman
  • Date: 2024-04-03
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/434651 , vital:73093 , DOI 10.21504/10962/434656
  • Description: The importance of dictionaries in society has been confirmed in relevant literature while their specific role in education is underlined by several studies focused on the use of dictionaries in teaching and learning. This study focuses on mother-tongue or first language (L1) isiXhosa learners and their use of dictionaries across subjects in the Intermediate Phase of primary schooling. The research sought to examine how dictionaries are used in teaching and learning and how they could be used more effectively in the teaching and learning processes, with a focus on isiXhosa L1 learners in the Makhanda area of the Sarah Baartman District of education, Eastern Cape. The general aim of this study was to improve the process and practice of using and producing Language for General Purpose (LGP) and Language for Specific Purpose (LSP) dictionaries across subjects. The study also sought to contribute to improving the functional value and user-friendliness of teaching support materials, such as dictionaries. The Curriculum and Assessment Policy Statement (CAPS) policy document states that dictionaries are essential in teaching and learning of both language and content subjects. In relation to language subjects, the CAPS is explicit about the use of dictionaries in the acquisition of vocabulary, meaning, spelling, pronunciation, and grammar, among other types of information that are integral in language attainment and learning. Nonetheless, the CAPS document does not clearly articulate the use of dictionaries in content subjects. The study draws on two branches of lexicography – namely, dictionary user research and dictionary criticism – to examine the extent to which dictionaries are problem-solving tools which assist users to meet their cognitive and communicative needs. Thus, the study seeks to influence policy and practice of the use of dictionaries as teaching and learning resource materials that could help teachers and learners better understand key concepts across subjects. A mixed-method approach was used to collect both quantitative and qualitative data using a variety of data collection instruments, viz., observation schedules, questionnaires, and interviews. The study found that although teachers were aware of dictionaries, they did not use them as a resource in teaching. Furthermore, teachers lacked skills in the use of dictionaries, therefore, they were not able to effectively integrate dictionaries in their lessons. The research also found that learners had little awareness of dictionaries and did not fully understand their role in language acquisition or content. Lastly, the study offered some insights on how dictionaries could be integrated in teaching and learning, and how their use could address some communicative and cognitive problems faced by non-mother tongue English speakers in a context where English dominates teaching and learning at the expense of learners’ L1. , Thesis (PhD) -- Faculty of Humanities, School of Languages and Literatures, 2024
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Electricity demand and supply in South Africa: is nuclear energy a feasible alternative to coal for baseload energy supply in South Africa?

  • Authors: Maqanda, Vuyani
  • Date: 2024-04-03
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/434802 , vital:73106 , DOI 10.21504/10962/434802
  • Description: Climate change mitigation has created pressure on the energy mix choices of all countries. Highly polluting energy sources are increasingly unpopular. Renewable energy options have emerged as preferred choices for the low-emissions transition. Proponents of nuclear power have promoted the technology as a low-emissions technology by focusing on the operational phase and ignoring the other polluting phases. South Africa generated about 83% of its electricity supply from coal in 2019 and was rated as the 12th most polluting country in the world. In addition to the high pollution levels, the ageing coal fleet suffered from poor maintenance that resulted in frequent power blackouts. One of the government’s energy plans from 2010 proposed the addition of 9 600 MW of nuclear capacity by 2030. However, this plan was not implemented. This study investigates why nuclear power historically never expanded beyond a single power facility in South Africa as well as the possible future role of nuclear power in alleviating South Africa’s current electricity supply constraints and emissions commitments in the period up to 2050. Qualitative analysis is used for this study with a focus on historical document analysis and interviews with energy experts. Two research methods, case studies, and expert opinions were used in this study with data sourced from policy documents, Statistics South Africa, the World Bank, and published articles from various platforms. The Hotelling model, focusing on the impact of price differentials on energy transitions, was used as a theoretical framework. The conclusion from applying the model was that nuclear power was more expensive than the other options even when internalisation of pollution externalities was considered and therefore nuclear power could not displace the cheaper alternatives like coal based on price factors alone. The Multi-Level Perspective, working through institutions, revealed that the institutional setting did not support a transition to nuclear energy. The lack of coordination of strategies derailed the transition. The comparative case study analysis of Germany, the UK, Australia, and India reaffirmed this as countries with better coordination succeeded in transitions. Energy experts offered differing views on the feasibility of nuclear power but many agreed that South Africa should focus on technologies it has better competencies in. , Thesis (PhD) -- Faculty of Commerce, Economics and Economic History, 2024
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Garden bird ringing at 3 Florence Street, Oatlands, Mkhanda (Grahamstown): the closing chapter

  • Authors: Craig, Adrian J F K
  • Date: 2024
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/449836 , vital:74856 , https://doi.org/10.15641/bo.1500
  • Description: This is the third and final report summarizing 42 years of bird ringing in a garden in Mkhanda. In total, 2036 birds of 59 species were ringed, of which 217 individuals (27 species) were recaptured at least once, and 34 birds (17 species) were recovered dead.
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