List of Titles

Genetic connectivity of the slinger Chrysoblephus puniceus among Marine Protected Areas and unprotected areas along the east coast of South Africa

- Ockhuis, Samantha Angelique Natasha

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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Date Issued: 2024-04-05

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The role of hashtag activism in advocating against gender-based violence and promoting perpetrator accountability : subtitle if needed. If no subtitle follow instructions in manual

- Nontyi, Antonnet

Authors: Nontyi, Antonnet
Date: 2024-04
Subjects: Gender based violence , Victims of violent crimes , Women -- Crimes against -- South Africa
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10948/63421 , vital:73356
Description: This study is aimed at determining the role that hashtag activism has played in advocating against gender-based violence (GBV) and promoting perpetrator accountability. The study used major GBV hashtags such as #MeToo, #WhyIStayed and #AmINext to investigate how effective these hashtag movements have been in breaking the silence around GBV and fighting against GBV. The study made use of both qualitative and quantitative research methodology, which was useful to gain a deeper understanding of GBV and all the social and cultural practices that perpetuate it. Qualitative data were collected by means of interviews and tweets under the selected hashtags. An online survey questionnaire was used to collect quantitative data. The data provided an understanding of the complexities surrounding GBV and people’s views on hashtag activism and GBV. Through the data analysis, the study found that hashtag activism has been effective in changing dominant discourses, advocating against GBV, creating awareness and solidarity around GBV issues, and promoting perpetrator accountability. The study calls for a global collective effort to develop, record and archive feminist initiatives so that all the structural conditions which enable and perpetuate sexual violence are exposed and cannot be forgotten or ignored. Future research should look into how harmful societal norms can be challenged and how the effectiveness of hashtag movements can be enhanced , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2024
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Date Issued: 2024-04

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The role of angling-guides in promoting pro-environmental catch-and-release attitudes and behaviours in the recreational angling community

- Farthing, Matthew William

Authors: Farthing, Matthew William
Date: 2022-04-08
Subjects: Fishing , Fishing Catch effort , Fishing guides , Fishers , Human behavior , Role models
Language: English
Type: Academic theses , Doctoral theses , text
Identifier: http://hdl.handle.net/10962/294583 , vital:57235 , DOI 10.21504/10962/294585
Description: Angling-guides are respected as opinion leaders of the recreational angling community, but nothing is known of their influence on angler behaviour. Given their social-standing, angling-guides may be perceived as role-models by angling-clients – thereby promoting the adoption of best and/or poor catch-and-release (C&R) practices, depending on their individual knowledge, attitudes and behaviour. It is critical to understand their potential influence, their knowledge and their behaviours to inform effective intervention strategies which could exploit their extensive networking potential. The aim of this thesis was to better understand the potential utility of angling-guides in efforts to improve angler behaviour. Firstly, this was done by investigating whether angling-guides are perceived as role-models by angling-clients (Chapter 2). Secondly, it was done by assessing the current level of knowledge, attitudes and behaviours of angling-guides from around the world (Chapter 3). Thirdly, it was done by exploring the relationship between angling-guide knowledge, attitudes, intentions and actual behaviour in a case-study of guided-angling trips (Chapter 4). Lastly, it was done by exploring intervention frameworks and incorporating insights into potential strategies for promoting pro-environmental angling behaviours to angling-guides (Chapter 5). To understand if angling-guides are perceived as role-models by the recreational angling community (Chapter 2), a digital survey was designed to assess previous angling-clients’ attitudes towards angling-guides serving the three role-model functions proposed in the Motivational Theory of Role-Modelling, namely as Behavioural models, Representations of the Possible and Inspiration. Of the 492 angling-clients (27 countries), most agreed that angling-guides were competent, skilled, and worth emulating (91.1%), suggesting they are perceived as Behavioural Models. Less agreed that angling-guides were Inspirational or Representations of the Possible (54.8%), suggesting they are less likely to motivate anglers to adopt and/or pursue new goals. As Behavioural Models, angling-guide C&R practices are likely to be emulated, which is of both utility and concern to managers. As angling-guides are likely to be emulated, a digital survey was designed to assess their knowledge, attitudes and behaviours (particularly C&R best-practices) (Chapter 3). Of the 342 angling-guides (47 countries), few had accredited training (9.4%). However, most were deemed “knowledgeable of best-practices” (69.0%), but pervasive misconceptions of key C&R best-practices were observed. Attitudes towards best-practices were generally pro-environmental, and those deemed knowledgeable had significantly more pro-environmental attitudes (p = 0.003). Most angling-guides had pro-environmental attitudes towards their environmental responsibilities (87.1 - 89.5%), but these broad attitudes cannot predict specific pro-environmental behaviours during guided-angling trips where angler satisfaction is often at odds with best-practice. Angling-client satisfaction has important financial implications for angling-guides, and even those with pro-environmental intentions may struggle to adhere to C&R best-practices with inherent sacrifices for the angling-client’s enjoyment. Observation of behaviour in context is critical for understanding the behaviour to be changed. To explore the relationship between angling-guide knowledge, intentions and actual behaviour (Chapter 4), five angling-guides were observed (and filmed) interacting with groups of angling-clients during their guided-angling trips over a 30 day period. Five angling behaviours of interest were identified, and a survey focussed on these behaviours was disseminated (18 months later) to the five angling-guides previously observed to assess their knowledge, attitudes, reported behaviours and perceptions of the norm. Generally the subjects’ reported behaviours aligned well with their knowledge of best-practice, but their actual behaviour was not well aligned (24.4%). Instead, their actual behaviour aligned better with their perceptions of the norm (80.9%), which was generally a “worse” practice than what they reported. Angling-guides appeared to favour client-satisfaction over pro-environmental behaviour. Gaps between angling-guides’ knowledge of best-practice and their actual behaviour indicate that there may be obscure and complex barriers to pro-environmental angling-guide behaviour. Many barriers are seemingly impossible to overcome, such as economic limitations and financial disincentives. These barriers may limit the efficacy of traditional knowledge-attitude-behaviour (KAB) change interventions. The strong alignment of angling-guide behaviour with social norms, and the strong community orientation of recreational angling suggests that the Community-Based Social Marketing (CBSM) approach may be a more effective framework for interventions that aim to promote pro-environmental catch-and-release behaviours at angling-guide level. The CBSM approach allows interventionists to leverage a larger suite of cognitive biases than KAB approaches, provided that sufficient understanding of the context, barriers and benefits for a given segment of the angling-guide community (likely defined by style-of-participation) are obtained. Furthermore, the success of the CBSM approach will depend on the ability of interventionists to effectively recruit and incentivise disjunct and isolated communities of angling-guides to participate in training and workshops in order to achieve the important in-person contact on which the CBSM approach depends. , Thesis (PhD) -- Faculty of Science, Ichthyology and Fisheries Science, 2022
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Date Issued: 2022-04-08

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An evaluation of the socio-economic costs and benefits of the invasive Rubus (Blackberry/Bramble) genus at selected sites in South Africa

- Mason, Brett Anthony

Authors: Mason, Brett Anthony
Date: 2021-10-29
Subjects: Rubus South Africa Cost effectiveness , Invasive plants South Africa Cost effectiveness , Rubus Economic aspects South Africa , Ecology Economic aspects South Africa , Rubus Ecology South Africa , Environmental economics South Africa
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/191931 , vital:45180
Description: Rubus L. (brambles, blackberries, raspberries, or dewberries) are a globally recognised genus due to the edible fruit and negative impacts they can have as invasive species. There are at least 23 species of Rubus subgenus Rubus in South Africa. These include native, alien, naturalised alien, and invasive alien species. The invasive Rubus species are becoming an increasing problem in South Africa with experts in invasion biology urging caution regarding the genus (Henderson, 2011). The taxonomy of indigenous, alien and alien invasive species of Rubus are poorly understood and therefore efforts to understand the genus, the impacts and solutions to those impacts have been very limited (Stirton, 1981; Henderson, 2011; Sochor et al., 2018a). There has also been little research conducted on the economic or ecological impacts on the species or genus of species in South Africa (du Plessis et al., 1984; Botha, 2005), and yet species in the genus have been earmarked for prioritization by invasive species legislation. The potential value of certain species as well as the cost associated with their impacts could potentially create a complex conflict of interest scenario which has not been investigated. This study is an effort to inform future policy decisions regarding this suite of species by investigating the economic impacts of the invasive Rubus species. A method was developed unique to the study that incorporated research tools from environmental economics and geography to identify the nature of interactions between economic agents, experts, and alien and invasive Rubus species in South Africa. Two questionnaires were developed to generate economic data and ground proofing was used to develop geographic data. One questionnaire was directed specifically at researchers and academics that attended the 46th National Symposium on Biological Invasions that took place between 15–17 May 2019, at Waterval Country Lodge, Tulbagh and the other an economic agent questionnaire for economic agents that met strict and selective criteria relating to the impact of the six invasive Rubus species on their economic activity. Both questionnaires were designed with a mixed methods approach in mind. The ground proofing was aimed at understanding the composition and distribution of Rubus species at the selected sites: Cathcart and Hogsback (The Eastern Cape Province), Clarens (Free State Province), and Underberg (KwaZulu-Natal Province). The study established that all economic impacts of invasive Rubus species at selected sites are externalities. Invasive Rubus species in South Africa can be attributed as (i) harbouring vermin, (ii) impeding human and animal livestock, (iii) reducing crop yields, (iv) encroaching on grazing land, (v) presenting fire hazards, and (vi) negatively impacting fire regimes. These species also (i) provide berries that are retailed on a commercial level, or have been, (ii) that are utilized for personal consumption, (iii) provide an ingredient for alcohol brewing processes, and (iv) could potentially facilitate forest regeneration. The invasive species are infrequently browsed by certain livestock and far as we could ascertain do not provide ingredients for anti-inflammatory drugs or modern cosmetics in South Africa, as they do in other regions of the globe. The costs associated with the invasive species can be presented dichotomously; the estimated private cost-benefit ratio, for costs and benefits incurred or enjoyed by 18 private economic agents, stands at 0.33:1. A private-public benefit-cost ratio, that incorporates both private and public costs and benefits, stands at 13,5:1. The private-public benefit-cost includes public expenditure, or government control measures, directed at invasive Rubus and shifts the benefit-cost ratio so that costs now markedly dominate the estimated benefits. The benefits per hectare uncovered in this study stand at R13.14/ha. The private costs stand at R4.32/ha and a holistic cost, including both private and public expenditure, stands at R177,43/ha. The monetary values, when expressed per hectare, are misleading. This is due to a large standard deviation in the spread of benefits received. The benefits are enjoyed by a small number of the already small sample of respondents. The costs and benefits are not uniformly distributed across regions assessed. All benefits in this study accrue to economic agents in the Free State Province, whilst most of the costs accrued to economic agents in KwaZulu-Natal Province. The benefits appear to be primarily derived from an alien species, Rubus sect. Arguti. Management of the 6 species of invasive Rubus could be optimised by the prioritisation of those regions that incur the highest cost and derive the lowest benefit, in this case KwaZulu-Natal Province. Likewise, those regions with the highest benefits and lowest costs, the Free State Province, could provide sites for increased use and beneficiation of berries from invasive species. Management of individual species may prove difficult, given the similar morphologies, and thus, (i) either specialised training for those engaged in control must be instituted, (ii) all species of alien Rubus should be earmarked for management, or (iii) highly specific biocontrol agents for the most problematic species must be found. , Thesis (MEcon) -- Faculty of Commerce, Economics and Economic History, 2021
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Date Issued: 2021-10-29

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The role of funding composition on efficiency in public universities in South Africa

- Nkohla, Tumi Vuyolwethu https://orcid.org/0000-0003-2426-9509

Authors: Nkohla, Tumi Vuyolwethu https://orcid.org/0000-0003-2426-9509
Date: 2020-08
Subjects: Education, Higher -- Finance
Language: English
Type: Doctoral theses , text
Identifier: http://hdl.handle.net/10353/20373 , vital:45659
Description: Studies on the relationship between funding and efficiency of public universities in South Africa were triggered mainly by the decline of government spending on public universities while the enrolment of financially needy students is increasing. This increase is a product of government’s initiatives to redress the imbalances in access and success caused by the apartheid regime. However, the government seems to be grappling to strike a balance between its initiatives and funding. While the government’s HE transformation initiatives are appreciated, public universities are caught in a dilemma: their revenue is no longer sufficient for the operations given the increase in the number of unfunded and financially constrained students. It is with this background that the study evaluates the efficiency of public South African universities for the period 2009–2016 and how funding composition affects their efficiency. The study contributes to the existing literature in various ways First, a recent study on this subject matter found a decline in the average technical efficiency (TE) score of the South African public universities from 83percent in 2009 to 78percent in 2013. However, the study did not include non-academic staff among other input variables that are assumed to potentially influence performance outcomes of the universities. We therefore developed an argument that a biased conclusion on the subject matter is likely, if academic staff are assumed to dominate efficiency of public universities in South Africa while the efforts of non-academic staff are not considered. Using a Data Envelopment Analysis (DEA) model, the findings of this study revealed that over the study period the average TE of public universities in South Africa increased from 91percent to 95percent. These results suggest that academic and non-academic staff can be deemed as mutually inclusive variables and therefore neglecting either of them can lead to biased estimated average TE scores. The efficiency levels provided in this study can be used as performance benchmarks for identifying potential improvements required to reach a satisfactory level of efficiency. Second, the literature argues that different streams of revenue utilised for funding universities’ activities can provide alternative incentives which might have an impact on efficiency. However, none of the studies examined comparatively the impact of different revenue streams on the efficiency of the public universities in South Africa. Using a fixed-effects regression model, this study found that only traditional universities’ efficiency can be affected by student fees and private income, while government funding does not seem to bear a significant impact on the efficiency of all universities irrespective of their category. Precisely, student fees enhance the efficiency of traditional universities while private income is deleterious on the efficiency of the traditional universities. The study concluded that traditional universities use students’ fees efficiently to deliver quality academic services in a bid to safeguard their reputation and image while revenue from private funders is not efficiently utilised due to the principal-agent problem. In terms of state funding, it was concluded that government spending on public universities is yet to reach a minimum threshold level at which it can contribute significantly to the efficiency of the universities. Third, recent literature used Stochastic Frontier Analysis (SFA) efficiency scores to determine the drivers of efficiency of public universities in South Africa. Although SFA can control for the stochastic error component in the econometric estimation, the model imposes several theoretical assumptions in the production function which may lead to biased estimations. As a result, several studies on efficiency analysis of Higher Education Institutions (HIEs) around the globe have reverted to using DEA. Using DEA efficiency scores and a Tobit model, this study found that that quality of staff, government funding, student fees, private income, and GDP per capita are positive factors of efficiency while the share of non-white to white staff was found as the determinant of inefficiency. It was concluded that adequate funding and proper management of income by the universities, economic growth and employment of highly educated academic staff can increase efficiency levels of public universities in South Africa, whereas an increase of non-white to white staff in South African public universities is a threat to the universities’ efficiency. Overall, the findings of this study suggest that a cost-sharing framework is inevitable in the South African higher education (HE) system, particularly now that the government is heavily burdened due to the prevailing economic turmoil in the country. As a results, private funders and parents and/guardians are encouraged to honour their portion of obligations with universities. Due to limited funding across all sources, efforts dedicated to strengthen managerial competencies of public universities in South Africa can eliminate the principle-agent problem and therefore promote managerial efficiency. The South African government is encouraged to support its transformation initiatives on HEIs with adequate funding, otherwise the initiatives need to be revisited and revised to suit the current economic environment. Revision of these initiatives may include adjustment of the education standards such that state funding can be allocated to deserving students in terms of both finances and students’ performance starting from matric. , Thesis (PhD) -- Faculty of Management and Commerce, 2020
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Date Issued: 2020-08

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Vachellia erioloba (camel thorn) and microbial interactions

- Van Aswegen, Sunet

Authors: Van Aswegen, Sunet
Date: 2018
Subjects: Vesicular-arbuscular mycorrhizas , Cadmium , Rhizobacteria , Plant growth-promoting rhizobacteria , Acacia erioloba
Language: English
Type: Master's theses , text
Identifier: http://hdl.handle.net/10962/63716 , vital:28475
Description: Vachellia erioloba (camel thorn) is one of South Africa’s economically important tree species and therefore requires further investigation to improve its health and growth. Beneficial soil microbes have positive effects on plants through various mechanisms such as nitrogen fixation, phosphate solubilisation, indole acetic acid and siderophore production and biofilm formation. These traits enhance plant growth and protect the host plant against parasitic organisms that are present in soil. The arbuscular mycorrhizal (AM) fungi are well known for their beneficial symbiotic effects on host plants. The objective of this study was to determine the role of AM fungi and associated beneficial rhizobacteria in improving the growth of V. erioloba seedlings. Soil and root samples were collected from a farm in the Northern Cape, South Africa. Fifty-seven bacterial cultures were isolated from the soil and tested for plant growth promoting characteristics. Fourteen isolates showing at least four beneficial traits were molecularly identified using the GenBank database. The AM fungal and bacterial populations in the soil samples were assessed using Illumina sequencing. Sequences were identified using the MaarJAM and GenBank databases, respectively. Three separate pot trials were conducted to determine; 1) the effects of cadmium (Cd) on seedling growth; 2) the individual effects of three selected bacterial isolates and AM fungi alone and combined on seedling growth, and 3) the combined effects of the selected bacteria on AM fungal inoculated and uninoculated seedlings. Of the fourteen isolates the Enterobacter genera was the dominant species identified, with Acinetobacter, Pantoea and Bacillus each having one isolate. All were described as plant growth promoting rhizobacteria. One isolate from each genus, excluding Pantoea, was used in the pot trials. Three genera were identified in the AM fungal population that was assessed, namely Ambispora, Paraglomus and Glomus with Ambispora being the dominant genus. The bacterial population assessed showed a high diversity of bacteria from the Actinobacteria phylum being the dominant group. The results of the heavy metal pot trial showed that the symbiotic relationship between the seedlings and AM fungi increased the seedlings’ health and growth during heavy metal stress. The combination of bacteria and AM fungi increased growth parameters in all the inoculated seedlings, but not when compared to uninoculated seedlings indicating a possible competition for nutrients. The results were influenced by the presence of a nematode, which was suspected to have been seed borne. Further investigations on these interactions are required. Inoculation of AM fungi and selected PGPR is recommended for V. erioloba seedling production. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2018
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Date Issued: 2018

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