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A review of African praying mantises (Dictyoptera: Mantodea) incorporating molecular and morphological data

  • Authors: Roestof, Bruce
  • Date: 2024-10-11
  • Subjects: Biogeography , Mantodea Morphology , Mantodea Geographical distribution , Mantodea Classification , Sampling bias , Systematics
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464428 , vital:76510
  • Description: Praying mantises (Dictyoptera: Mantodea) are an iconic group of predatory insects, comprising around 2500 species globally, that occur in all zoogeographic regions except the poles. Their presence in the social psyche of many cultures has existed for millennia, but until the past decade, Mantodea has received little attention from the scientific community as the constituent species are of little economic or medical importance. Africa is rich in praying mantis diversity, accounting for approximately 45% of all described species, yet it remains largely under-sampled compared to the New World and Asian regions. Recent exploration of Gabon and Central African Republic have proved fruitful, with new species descriptions being major highlights. A recent re-cataloguing of southern African praying mantises has proved useful as specimen identifications were checked, new distributions were recorded, and most importantly, it was revealed that museum collections have significantly more diversity than previously recorded. A meta-analysis of African praying mantises was conducted; we present a species checklist to the countries of Africa, including Madagascar and surrounding islands. Currently, 17 families, 182 genera, and 1104 species occur in Africa.Historically, the classification of praying mantises was based solely on morphological features, and the novelty of the field at the time made it unclear which characteristics were of taxonomic importance. The onset of molecular systematics brought attention to incongruences between morphological and molecular phylogenies, believed to be attributed to convergent evolution masking the underlying evolutionary processes that occurred. Significant progress has been made in the past two decades regarding Mantodean classification and most described genera have their phylogenetic position. With the addition of more African taxa, we present mantodean phylogenies for molecular and morphological data. Molecular phylogenies were estimated through Bayesian Inference and Maximum Likelihood analyses using two nuclear (28S and H3) and two mitochondrial markers (16S and COI) for 210 individuals that represented 24 of the 29 families globally. Morphological phylogenies were estimated through Maximum Likelihood analyses of a morphological data matrix comprising 149 characters for 248 individuals that represent 24 families. The same data matrix was used to produce a key to all African mantodean families, accompanied by their descriptions. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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  • Date Issued: 2024-10-11

A revision of Late Devonian (Famennian) “thallophyte” (probable Rhodophyte and Phaeophyte) algae from the Witpoort Formation of South Africa

  • Authors: Reddy, Caitlin
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464955 , vital:76560
  • Description: Access restricted. Expected release in 2026. , Thesis (MSc) -- Faculty of Science, Geology, 2024
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  • Date Issued: 2024-10-11

A scoping review on problematic Internet use and Substance Use Disorder among men

  • Authors: Adolph, Miché Tania
  • Date: 2024-10-11
  • Subjects: Internet addiction , Substance abuse , Men Mental health , Scoping review protocol , Compulsive behavior Sex differences
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465788 , vital:76653
  • Description: Problematic Internet Use (PIU) and Substance Use Disorder (SUD) interact in complex ways that influence the current mental health landscape. Concurrently, the advent of the digital era has presented new difficulties, one of which is the emergence of problematic internet use as a significant issue that negatively impacts mental health. The increasing popularity of internet use has led to an increasing number of reports highlighting the potential negative consequences of overuse, such as substance use. Thus, the study aimed to synthesise literature on problematic internet use and substance use disorder, including the way in which they affect men, given that prior research has predominantly focused on women. The methods employed follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) which is largely based on a PRISMA statement and checklist, the JBI methodological guidance, and other approaches for undertaking scoping reviews. A total of 16 studies were eligible for final review, and the themes identified from the reviewed studies were obtained using Braun and Clarke’s thematic analysis. An analysis of the articles showed a large focus on gender differences in addiction patterns, vulnerability to problematic internet use across age groups, associations between substance use and behavioural addictions, problematic internet use and mental health disorders, the psychological consequences of problematic internet use and substance use disorders, and the various risk factors associated with the development of problematic internet use and substance use disorder. A clear understanding and conceptualisation of this behavioural addiction is vital, including the development and utilisation of appropriate and validated diagnostic and screening tools to measure its presence and, in turn, address it as an emerging mental health disorder. Focus should be given to the assessment of problematic internet use by distinguishing the two different forms, namely the generalised and specific forms of problematic internet use. Additionally, given that there were very few to no qualitative studies conducted on the topic of problematic internet use, much less addressing the possible association with substance use disorder, an assessment of the individual’s experience, especially that of men, is lacking. Future research could therefore aim to incorporate more qualitative studies to address the above. Further research is also needed to clarify the nature of the relationship between problematic internet use and substance use disorder for the purpose of establishing possible causality, including the neurobiological substrates involved. , Thesis (MA) -- Faculty of Humanities, Psychology, 2024
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  • Date Issued: 2024-10-11

A social realist account of the way smallholder farmers exercised their agency in the adoption of climate-smart agriculture practices in degraded landscapes in Machubeni, Eastern Cape, South Africa

  • Authors: Mbengo, Idah
  • Date: 2024-10-11
  • Subjects: Climate-smart agriculture , Climatic changes South Africa , Climate change adaptation South Africa Eastern Cape , Social realism , Farms, Small South Africa Eastern Cape
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466884 , vital:76795 , DOI https://doi.org/10.21504/10962/466884
  • Description: Over the last two decades, climate-smart agriculture (CSA) has been promoted as a way to address the challenges of climate change for smallholder farmers' productivity, food security and livelihoods. Given concerns about climate change, many studies have contributed to developing an understanding of resilience building and crop and livestock systems adaptation. Despite evidence of the effectiveness of CSA practices, several studies report on their limited uptake by farmers involved in various projects. The reasons for low rates of adoption remain unclear. In this context, the study on which this thesis is based drew on Bhaskar’s critical realism and Archer’s social realism to explore the way smallholder farmers in five villages in a rural area in South Africa were enabled and constrained as they exercised their agency in a project intended to introduce them to CSA practices. The study was not about adaptation and resilience building per se but rather, following Bhaskar and Archer, sought to identify the generative mechanisms enabling and constraining the adoption of CSA practices. Bhaskar’s critical realism posits a view of reality as layered. The topmost layer of reality is the Empirical. This consists of observations and experiences of the world around us and is understood to be relative. The second layer, the Actual, is the layer of events from which observations and experiences located at the level of the Empirical emerge. Events at the level of the Actual and experiences and observations at the level of the Empirical emerge from an interplay of mechanisms at the deepest layer of reality identified by Bhaskar, as the Real. In positing a layered ontology, critical realism allows for the relativity of experiences and observations while, at the same time, acknowledging the reality of structures and mechanisms, which cannot be directly observed but nonetheless exist. Archer’s work on agency accords personal powers and properties (PEPs) to all individuals. Although all individuals have the power to act in relation to the world around them, they are nonetheless conditioned by their previous histories and experiences as they do so. As individuals set about exercising their agency, they are enabled or constrained by structures and mechanisms in two domains at the level of the Real which are understood to possess their own powers and properties: the structural domain and the cultural domain. In addition to drawing on Archer’s conceptualisation of the interaction between agency, structure and culture, the study also uses her “morphogenetic framework” which allows for the identification of ‘whose conceptual shifts are responsible for which structural changes, when, where and under what conditions’ (Archer, 1998: 361) and for understanding change as a series of never-ending cycles. The first phase of Archer’s morphogenetic framework, entitled T1, involves social and cultural conditioning. In the study, T1 was understood to be the time until 2017 when the project on which the study focused began. The second phase, T2 to T3, is the phase of social and cultural interaction as agents exercise their PEPs to pursue concerns they have identified for themselves and encounter structural emergent powers and properties (SEPs) and cultural emergent powers and properties (CEPs) of mechanisms located in the domains of structure and culture as they do so. The final phase of the framework, T4, allows for an evaluation of what has changed and what has not changed. My claim is that the uptake of CSA practices is impacted by different forms of consciousness or ways of experiencing the world, which is the result of the social and cultural conditioning of different groups involved in the project at T1, and clashes between them. The use of the framework drawing on critical realism and social realism allowed for the identification of these different forms of consciousness in different social groups (project facilitators, elderly farmers and the youth). These different forms of consciousness were understood to condition the agency of the three groups and thus enable or constrain the introduction of CSA practices and how they were taken up. Elderly women in the project had been conditioned to be caregivers and to see their roles tending kitchen gardens as part of their identity. This consciousness led to the uptake of CSA practices in their home gardens. By contrast, young people engaged with the project shared a very different way of experiencing the world. They were better educated and had been socialised into using social media and watching films on electronic devices from a young age. As a result, they valued the role of money in accessing consumer goods and the good life and thus valued paid employment rather than working on the land to provide subsistence. This led to a limited uptake of CSA practices. It is envisaged that insights from the study will offer new ways of understanding what might otherwise be seen as resistance to adopting CSA practices as well as new ways of engaging with different groups of agents involved in projects in the future. The study demonstrates the explanatory power of critical realism and social realism to analyse a climate change adaptation project. , Thesis (PhD) -- Faculty of Science, Environmental Science, 2024
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  • Date Issued: 2024-10-11

A social realist analysis of health policy development: interests, ideas and community pharmacists

  • Authors: Allan, Lucie
  • Date: 2024-10-11
  • Subjects: Uncatalogued
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466328 , vital:76718
  • Description: Access restricted. Expected release in 2026. , Thesis (PhD) -- Faculty of Pharmacy, Pharmacy, 2024
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  • Date Issued: 2024-10-11

A social realist analysis of the professional identity formation of lecturers emerging from completing professional development at a South African research-intensive university

  • Authors: Adams, Anthea
  • Date: 2024-10-11
  • Subjects: Identity (Psychology) in education , Academic development , Staff development , Social realism , Critical realism , Scholarship of teaching and learning , Education, Higher South Africa
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466372 , vital:76722 , DOI https://doi.org/10.21504/10962/466372
  • Description: This doctoral study is part of a Department of Higher Education and Training (DHET) capacity development project, Phakamisa. Using Margaret Archer's Social Realism as a substantive theory and methodological tool and Roy Bhaskar's Critical Realism as a meta-theory, I was able to identify and explain the interplay between the structural, cultural and agential mechanisms within a professional development course that enabled or constrained the emergence of lecturers' professional academic identities. My research participants are fourteen lecturers who completed the Postgraduate Diploma in Higher Education (PGDip HE) at Rhodes University between 2007 and 2017. Social Realism's explanatory methodologies, analytical dualism, and the morphogenetic cycle allowed me to provide causal explanations and account for the historicity of the emergence of lecturers' professional academic identities as teachers. A qualitative research design involving case study research allowed me to search for generative mechanisms to understand and explain the conditioning influence of often unobservable phenomena and underlying mechanisms in developing lecturers' identities as teachers in a research-intensive university. As strong social actors imbued with power and material resources, university leadership should consider the constraining influence of contextual conditions, such as the hegemony of disciplinary research versus research in the Scholarship of Teaching and Learning (SoTL). The socio-cultural (S-C) interactions of the fourteen lecturers (agents) signal the possibilities for structural, cultural and agential morphogenesis when agents choose to exercise their agency, i.e., their personal emergent properties (PEPs) to mediate prevalent structural and cultural emergent properties (SEPs and CEPs) enabling or constraining their personal projects. Lecturers' personal projects are the courses of action they intentionally engage in as they strive to establish sustainable yet evolving practices as teachers in their disciplines. This thesis shows that exercising their PEPs involves subjective reflexivity and transforming from primary agents to corporate agents due to collective action and alliances with like-minded peers and colleagues to shape the teaching and learning agenda in their respective departments and the broader higher education context. Triple morphogenesis of lecturers' agency occurred through their realisation as social actors. It signified the formation of their professional identities as teachers and how they uniquely embodied and enacted their teacher roles. , Hierdie doktorale studie is deel van 'n Departement van Hoër Onderwys en Opleiding (DHOO) kapasiteitsontwikkelingsprojek, naamlik Phakamisa. Deur gebruik te maak van Margaret Archer se Sosiale Realisme ("Social Realism") as 'n substantiewe teorie en metodologiese instrument, en Roy Bhaskar se Kritiese Realisme ("Critical Realism") as 'n metateorie, was ek in staat om die wisselwerking tussen die strukturele, kulturele en agentiese meganismes binne 'n professionele ontwikkelingskursus te identifiseer en te verduidelik wat die ontstaan van dosente se professionele akademiese identiteite moontlik gemaak of beperk het. Die deelnemers in my navorsing is veertien dosente wat die Nagraadse Diploma in Hoër Onderwys (NGDip HO) aan Rhodes Universiteit tussen 2007 en 2017 voltooi het. Sosiale Realisme se verklarende metodologieë, analitiese dualisme en die morfogenetiese siklus het my toegelaat om oorsaaklike verklarings te verskaf en die historisiteit van die ontstaan van dosente se professionele akademiese identiteite as onderwysers te verantwoord. ’n Kwalitatiewe navorsingsontwerp wat gevallestudienavorsing behels het, het my toegelaat om na generatiewe meganismes te soek om die kondisionerende invloed van dikwels onwaarneembare verskynsels en onderliggende meganismes in die ontwikkeling van dosente se identiteit as onderwysers in ’n navorsingsintensiewe universiteit te verstaan en te verduidelik. As sterk sosiale rolspelers deurdrenk met mag en materiële hulpbronne, behoort universiteitsleierskap die beperkende invloed van kontekstuele toestande, soos die hegemonie van dissiplinêre navorsing versus navorsing in die Akademieskap van Onderrig en Leer (AvOL, of in Engels "Scholarship of Teaching and Learning", afgekort na SoTL) in ag te neem. Die sosiokulturele (S-K) interaksie van die veertien dosente (agente) dui op die moontlikhede vir strukturele, kulturele en agentiale morfogenese wanneer agente doelbewus kies om hul agentskap uit te oefen, dit wil sê hul persoonlike ontluikende eienskappe (in Engels "personal emergent properties", afgekort na PEPs) om heersende strukturele en kulturele ontluikende eienskappe te bemiddel (in Engels "cultural emergent properties", afgekort na CEPs) wat hul persoonlike projekte moontlik maak of beperk. Dosente se persoonlike projekte is die aksies wat hulle doelbewus aangepak het terwyl hulle daarna gestreef het om volhoubare dog ontwikkelende praktyke as onderwysers in hul dissiplines te vestig. Hierdie tesis dui aan dat die uitoefening van hul persoonlike ontluikende eienskappe ("PEPs") behels subjektiewe refleksiwiteit en transformasie van primêre agente na korporatiewe agente as gevolg van kollektiewe optrede en alliansies met eendersdenkende eweknieë en kollegas om die onderrigen leeragenda in hul onderskeie departemente en die breër hoëronderwyskonteks te beïnvloed. Drievoudige morfogenese van dosente se agentskap het plaasgevind deur hul verwesenliking as sosiale rolspelers. Dit het die vorming van hul professionele identiteite as onderwysers aangedui en die unieke manier hoe hulle hul onderwyserrolle interpreteer en uitleef. , Thesis (PhD) -- Faculty of Education, Centre for Higher Education Research, Teaching and Learning, 2024
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  • Date Issued: 2024-10-11

A sociological study of women’s lived experience of menopause and understanding of menstruation in Mthatha and Makhanda, Eastern Cape Province

  • Authors: Makalima, Buthanani Vuyokazi
  • Date: 2024-10-11
  • Subjects: Menopause , Menstruation , Women South Africa Social conditions , Menopause Psychological aspects , Menstruation Social aspects
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466210 , vital:76707
  • Description: This qualitative study explored different sociocultural factors that influence and inform women’s menopause experience and perceptions. The aim of the study was to investigate the cultural beliefs about menstruation and menopause, with a focus on embodied experiences of menopause, as well as the perceptions of the transition from menstruation to menopause. Six in-depth interviews were conducted with women in their 60s and 70s in the Eastern Cape Province: four in-depth interviews were conducted in Umtata/Mthatha and two in Makhanda. Data was analysed thematically. A key study finding is that women’s definition and experience of menopause is significantly influenced by their sociocultural context. This also shapes their experience of menopause, and in the case of the women in this study, menopause is experienced as a natural process. Regardless of the participants’ acceptance of menopause, some women still need to be equipped with information on severe menopause symptoms, what they mean, and how they can be treated or managed. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

A spatial perspective of the population structure and connectivity of two small tuna species, Katsuwonus pelamis (Skipjack tuna) and Euthynnus affinis (Kawakawa), in the Southwest Indian Ocean

  • Authors: Taylor, Christopher John
  • Date: 2024-10-11
  • Subjects: Fishery management Indian Ocean Region , Geospatial analysis , Skipjack tuna , Euthynnus affinis , Fish populations Indian Ocean Region , Marine fishes Geographical distribution
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/467116 , vital:76816
  • Description: Katsuwonus pelamis and Euthynnus affinis are two small tuna species of socio-economic and fisheries importance across the Southwest Indian Ocean (SWIO). There is currently a dearth of data and information around various aspects of their biology in the SWIO, including their population structure and connectivity. The availability of such data, including spatially represented biological data, has the potential to address current management discrepancies through the provision of more robust assessments into the stock structure and connectivity of these species and their stocks. This study explored a spatial perspective of the population structure and connectivity of K. pelamis and E. affinis fisheries in the SWIO to determine the suitability of current Indian Ocean Tuna Commission (IOTC) management measures for the species. It employed two primary data sources: a) Western Indian Ocean Marine Science Association’s (WIOMSA) Marine and Coastal Science for Management (MASMA) Project and b) IOTC. WIOMSA MASMA and IOTC data was collected throughout many countries and small island states in the SWIO, and pertained to genetic diversity, catch-weight, length-at-maturity, and morphometrics. Such data were combined and analysed to conduct geospatial analysis. Spatially illustrated genetic divergence, length-at-maturity, catch-weight, and morphometric data supported the presence of three reproductively isolated subpopulations of K. pelamis in the SWIO (Dar es Salaam, Tanzania, and Kenya; Mtwara, Tanzania, Mozambique, and Eastern Cape, South Africa; Seychelles). Only spatially depicted genetic divergence data, and morphometrics, supported that E. affinis populations were not panmictic in the SWIO, with genetic divergence data supporting the presence of three reproductively isolated subpopulations of E. affinis (Northern Mozambique and Kenya; Tanzania; Seychelles). Spatially illustrated length-at-maturity and catch-weight data however did not provide sufficient evidence supporting spatial structuring among E. affinis populations in the SWIO. Whilst the present analyses are not definitive to delineate exact stock boundaries, findings supported the contention of current IOTC management policy, indicating spatial population complexity for both species. Future research must increase representation of fishery independent samples and must investigate oceanographic variables driving potential stock separation to further support effective management reform. Until available, a precautionary approach should be adopted for the management of these species across the SWIO, considering the presently proposed distribution of their stocks separate for management. , Thesis (MSc) -- Faculty of Science, Ichthyology and Fisheries Science, 2024
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  • Date Issued: 2024-10-11

A study exploring women’s experiences, knowledge, attitudes, and perceptions of fibroids in Diepsloot, South Africa

  • Authors: Nwanamidwa, Moreblessing Itani
  • Date: 2024-10-11
  • Subjects: Uterine fibroids , Reproductive health , Women's health , Women Health and hygiene South Africa Johannesburg , Health attitudes , Traditional medicine South Africa , Diepsloot
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466071 , vital:76682
  • Description: This study is an exploration of women’s experiences, knowledge, attitudes, and perceptions of fibroids. It is underpinned by social constructionism and the common-sense model of self- regulation theoretical frameworks. Eight in-depth semi-structured interviews were conducted with women in Diepsloot, South Africa. The study aimed to include diverse perspectives, thus participants included women who consulted biomedical and cultural practitioners or both. The findings of the research reveal that women’s experiences with fibroids are complex because of the many decisions they have to make about the diagnosis and treatment options and the multiple, and sometimes intersecting temporary disruptions, caused by fibroids. Furthermore, the low levels of awareness about fibroids and the prevailing culture of silence surrounding women’s reproductive health have negative consequences for women living with fibroids as this can result in delayed diagnosis and treatment. The findings highlight the importance of raising awareness about fibroids in communities such as Diepsloot where awareness initiatives are insufficient, given the high prevalence of fibroids among reproductive age black women. , Thesis (MA) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

A systematic revision of Aprionyx Barnard, an endemic South African genus of Leptophlebiidae (Ephemeroptera)

  • Authors: Ferreira, Ina Susan
  • Date: 2024-10-11
  • Subjects: Biogeography , Leptophlebiidae Geographical distribution , Leptophlebiidae Morphology , Leptophlebiidae Phylogeny , Leptophlebiidae Classification
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466770 , vital:76777 , DOI https://doi.org/10.21504/10962/466770
  • Description: Aprionyx Barnard, 1940 is the most speciose genus of Leptophlebiidae in South Africa and endemic to the southern region. Like the other African Leptophlebiidae, Aprionyx has received limited research. The earliest described Aprionyx species were based only on adults that were then placed in Atalophlebia Eaton, 1881. The first descriptions of nymphs were contributed by Barnard (1932), with the smooth claws of the nymphs being the distinctive feature that allowed him to create Aprionyx for all of the South African species placed in Atalophlebia at that time. This research aimed to improve knowledge of Aprionyx species by revising its molecular and morphological systematics. Molecular phylogenetic analysis of the COI, 16S and 28S genes generated a species tree illustrating the species’ relationships within Aprionyx. Species delimitation analyses (bPTP and GMYC methods) were generally congruent with the molecular phylogenetic species composition. The phylogeny identified up to ten potentially new species, a substantial increase in the species diversity of Aprionyx. Review of the descriptions of the eight named Aprionyx species resulted in major nomenclatural changes concerning A. tabularis (Eaton, 1884), A. phoeocera (Lestage, 1924) stat. rev. and A. intermedius Barnard, 1932 n. syn. With the redescriptions of all currently known species, the nymph of A. rubicundus Barnard, 1932 was described for the first time. An identification key to the species of Aprionyx was compiled from newly recognized descriptive characteristics and, for the first time, includes both imagos and nymphs. Molecular and morphological phylogenetic analyses recovered Aprionyx as monophyletic, although this was poorly supported morphologically. The phylogenies were topologically congruent and identified two clear geographically separated clades, a western and eastern Aprionyx group. Molecularly, morphologically and geographically, these two clades were recovered as two clearly distinct groups within the genus. The analyses further identified three lineages in Aprionyx: rubicundus, pellucidulus and eastern Aprionyx. The estimated age of Aprionyx indicated that initial diversification occurred during the Cretaceous (approximately 100 ma). Aprionyx peterseni (Lestage, 1924) was shown as the oldest of the analysed species, and the main drivers to species diversification were possibly the glacial cycles of the Quaternary period, through the mechanism of river anastomosis during fluctuating sea levels. Further research is needed to strengthen the support for the hypothesis identified in this study, but a substantial foundation has been laid by this work for future research, conservation and environmental decision-making. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2024
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  • Date Issued: 2024-10-11

Activist radio and the struggle to empower audiences: a case study of the Zimbabwean history

  • Authors: Chaunza, Garikai
  • Date: 2024-10-11
  • Subjects: Activism Zimbabwe , Radio broadcasting Political aspects Zimbabwe , Authoritarianism Zimbabwe , Democracy Zimbabwe , Zimbabwe Social conditions , Zimbabwe Politics and government
  • Language: English
  • Type: Academic theses , Doctoral theses , text
  • Identifier: http://hdl.handle.net/10962/466907 , vital:76797 , DOI https://doi.org/10.21504/10962/466907
  • Description: This study is grounded in my 18-year career in journalism in Zimbabwe. This journey began in January 2006 at the Zimbabwe Broadcasting Corporation (ZBC), where I started as a news reporter. In June 2008, I left ZBC and transitioned to freelance roles, including work at Radio Voice of the People (VOP), which broadcasted from South Africa using Radio Netherlands' transmitters in Madagascar. Simultaneously, I corresponded for The Zimbabwean Newspaper, edited in the UK, printed in Johannesburg, South Africa, and distributed to Zimbabwe, Radio Netherlands, Free Speech Radio News (USA), KPFA Pacifica Foundation Radio (USA), and DW (German). More recently, my work has expanded into the digital domain, contributing to New Zimbabwe, an online newspaper for the Zimbabwean diaspora in the UK, before transitioning to Community Radio Harare. Throughout my 18-year career as a media practitioner and journalist in Zimbabwe, I faced constant state-sanctioned interference, and even physical violence, while executing my responsibilities. Initially, at the Zimbabwe Broadcasting Corporation (ZBC), several colleagues and I, including our news editor, were politically victimised and ultimately fired for covering opposition political players and human rights activists. Later, when I was operating outside state-established media outlets, I experienced a series of threats, intimidation, arrests and detentions by state security. This was also true during my six-year tenure as the chairperson of the Media Institute of Southern Africa's Harare advocacy committee. This experience underscored the importance of studying the history of media activism in this country, focusing on the role that activists have played sustaining the alternative media despite intimidation by the state. I am convinced of the importance documenting their experiences, capturing their contribution to the creation of alternative communication platforms for marginalised audiences. In exploring the literature I discovered that the traditions of activist media, in which I have been involved myself, are rooted in a much older history that can be traced back to pre-independent Zimbabwe. At that time, colonial authorities also restricted media freedoms and employed violence against pro-democracy activities, referred to as nationalists. I decided, for the purpose of this study, to delve into this pre-history of media activism in Zimbabwe, focusing on radio in particular. I wished to gain insight into the way media activists have, over time, sustained their involvement in the traditions of radio practice that can empower marginalised communities. I was conscious that the continued survival of activist radio in this country has often been arduous, with activists facing harassment, arrests, and detentions by authoritarian administrations resisting the opening up of democratic spaces. I wished to trace this history of resistance from its origins in the mid-twentieth century to the time of my own involvement in such radio in the 21st century. In particular, I hoped to identify shared normative foundations as well as shared practices for the implementation of these ideals. Chapter One of the study explores the history of activist radio from the mid-20th century to the present, identifying five distinct phases in Zimbabwe's socio-political history and illustrating how each phase shaped the media landscape. Building on this, Chapter Two establishes a theoretical framework underpinning the values and principles driving media activists to create people-oriented radio projects to empower marginalized communities. Chapter Three delves into the documented history of activist radio within the broader context of media activism in Zimbabwe, engaging with each of the five key moments detailed in Chapter One. Chapter Four outlines the research plan for the empirical fieldwork and discusses its implementation. In Chapter Five, I present interviews with radio activists from the 1970s' nationalist radio and those involved in the pirate radio tradition that re-emerged at the turn of the millennium, sharing their practical experiences. Chapter Six focuses on interviews with community radio advocates, detailing their involvement in radio activism during the first decade of the millennium. Finally, Chapter Seven examines the activities of community radio practitioners, exploring their experiences with unlicensed radio projects and highlighting their creative endeavours. , Thesis (PhD) -- Faculty of Humanities, Journalism and Media Studies, 2024
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  • Date Issued: 2024-10-11

An analysis of tax incentives offered for investments by individuals in South Africa and the United Kingdom

  • Authors: Muzenda, Nokuthula Tafadzwa
  • Date: 2024-10-11
  • Subjects: Investments Taxation South Africa , Investments Taxation Great Britain , Tax incentives , Venture capital , Pensions , Life insurance endowment policies , Annuities , Savings bonds
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/463516 , vital:76416
  • Description: This research analysed the tax incentives available for investments by individuals in South Africa and compared them to investments in the United Kingdom. It answered the question whether, based on incentives provided in the United Kingdom, recommendations can be made for investment incentives to be implemented in South Africa. The type of investments described were venture capital schemes, tax-free investments, retirement savings, endowment policies, purchased annuities, workplace investment schemes, and fixed interest bonds. These classes of investments were discussed together with the tax incentives offered for them in South Africa and the United Kingdom. An interpretative paradigm was adopted for this research, together with a doctrinal methodology and a qualitative method. This research analysed the legislative provisions in South Africa and the United Kingdom. Information was also collected from secondary sources such as textbooks and articles written on investments and taxes. There were no ethical considerations in this research as the data that was used are publicly available. The tax incentive provisions in South Africa have not proven to be effective in increasing household savings, which remain low. The comparison of the taxes and incentives in South Africa and the United Kingdom indicated that there are some similarities on how certain investments are taxed, but for most types of investments, the United Kingdom provided more favourable tax incentives than South Africa. Recommendations were made for the venture capital company incentive previously applying to be reinstated, or to introduce some form of income tax and capital gains tax relief for direct investment into venture capital companies. The removal of the penalty for tax-free investments in excess of the maximum permitted was recommended, and to charge income tax according to the tax tables on contributions exceeding the limit. With regard to purchased annuities, it was recommended that no income tax should apply to annuities received in the case of disability, sickness, and similar circumstances. For the section 8B Broad-Based Share Incentive Scheme recommendations were made to not levy dividends tax on cash dividends retained for reinvestment into the scheme, and for employees not to be liable for income tax when shares are disposed of, where they are no longer in the relevant employment due to circumstances beyond their control. A recommendation was also made to consider introducing workplace savings schemes similar to the savings schemes applying in the United Kingdom. An education campaign by the South African Revenue Service was recommended, to inform the public of investment incentives. , Thesis (MCom) -- Faculty of Commerce, Accounting, 2024
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  • Date Issued: 2024-10-11

An analysis of the precarious livelihoods of Zimbabwean migrants in the informal economy in Makhanda, South Africa

  • Authors: Nderere, Nompumelelo Agnes
  • Date: 2024-10-11
  • Subjects: Precarious employment , Informal sector (Economics) South Africa Makhanda , Foreign workers, Zimbabwean South Africa Makhanda , Sustainable livelihood , Gig economy
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466262 , vital:76712
  • Description: The movement of people across borders is a complex phenomenon that has far-reaching social, political, and economic implications. In recent years, Zimbabwean migrants have become increasingly visible in the informal economy across South Africa. Through qualitative data collection methods, this study sought to broaden our understanding of the precarious livelihoods of Zimbabwean migrants working in the informal economy in South Africa. This study examined Zimbabwean migrants in the informal economy in Makhanda, Eastern Cape in South Africa. Underpinned by the Sustainable Livelihoods Approach (SLA) as the theoretical anchor, this thesis offers a comprehensive examination of not only the challenges but also the opportunities faced and presented to Zimbabwean migrants in the informal economy in Makhanda. The Sustainable Livelihoods Approach was used as a framework to guide the analysis aimed at understanding the precarious livelihoods of Zimbabwean migrants working in the informal economy in terms of the vulnerability context they find themselves in, the assets they use, the organizations or institutions that affect their activities and the results they get out of their efforts in the informal economy. Data was collected from a sample of 10 participants, consisting of 4 self-employed participants and 6 “employed” in the informal economy. Through in-depth interviews and thematic analysis, this thesis examined the strategies that the migrants adopt to cope with the challenges they face and the impact that these strategies have on their livelihoods. The findings suggest that working in the informal economy evolves as a sustainable livelihood strategy, which depends on external support for it to flourish. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

An assessment of the status of psylloid species (Hemiptera: Psylloidea) as potential pests of commercial citrus in southern Africa: implications for pest management

  • Authors: Moagi, Raynold
  • Date: 2024-10-11
  • Subjects: Citrus Diseases and pests South Africa , Candidatus Liberibacter , Psylloidea , Polymerase chain reaction , Insect trapping Equipment and supplies , Pests Control
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/464417 , vital:76509
  • Description: Psylloids (Hemiptera: Psylloidea), constitute a group of plant sap-sucking insects, some of which are economically significant pests in different ecosystems due to their potential to transmit Gram-negative bacteria, such as the Candidatus Liberibacter species. The African citrus triozid (ACT), Trioza erytreae (Del Guercio), which transmits African citrus greening and the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, which transmits Asian citrus greening are significant threats to citrus. Asian citrus psyllid poses a global economic threat due to its ability to vector “Candidatus Liberibacter asiaticus” (CLas), which can rapidly kill citrus trees. However, both ACP and CLas are currently not present in southern Africa but are present in East and West Africa. In the Afrotropical region, 71 triozid species are known to occur and approximately 41 described Diaphorina species in southern Africa. Currently, two indigenous Diaphorina species, Diaphorina punctulata and Diaphorina zebrana have been documented to feed on citrus. There is a significant knowledge gap regarding the ecological roles of other indigenous psylloid species occurring within the citrus environments. Therefore, this study aimed to: (i) determine the diversity and community structure of psylloid species in citrus environments, and (ii) their host ranges through DNA analysis of gut contents to determine if they fed on citrus. Field surveys were carried out across 12 distinct commercial citrus environments across Limpopo and Mpumalanga provinces between 2022 and 2023. Psylloids were collected using yellow sticky traps and an insect sweep-net. Collected psylloid specimens were preserved in 70% ethanol vials and identified to the lowest possible taxonomic level (i.e. genus or species) using both published and unpublished dichotomous identification keys. Furthermore, citrus leaf samples were collected from the same plants on which psylloids were found in the orchards. Genomic DNA (gDNA) was extracted from both leaf and psylloid samples using two different DNA extraction methods. To confirm if citrus DNA could be detected in the psylloid guts, all leaf gDNA samples were initially amplified using the rbcLaF/R primer pair, targeting a 530-bp region of the chloroplast rbcL gene through the polymerase chain reaction (PCR). Lastly, gut content analysis was performed on 11 psylloid species using the same primer pair through PCR to detect citrus DNA. A total of 4,900 psylloids belonging to five families (i.e. Aphalaridae, Carsidaridae, Liviidae, Psyllidae and Triozidae), 19 genera and 47 species, were collected in citrus environments. More psylloids were recorded in Limpopo (3,754) than in Mpumalanga (1,146). The most abundant species were Pauropsylla trichaeta (1,680), followed by Diaphorina punctulata (466), Trioza erytreae (426), Diaphorina virgata (371), Euryconus sp. (358), Cacopsylla sp. (311), Retroacizzia mopanei (263), Acizzia russellae-group (240), Acizzia sp.3 (216) and Acizzia sp.2 (140). Yellow sticky traps captured 3,265 psylloids in citrus orchards, while an insect sweep-net collected 1,635 psylloids (477 from citrus orchards and 1,158 from adjacent natural vegetation). Data from the insect sweep-net revealed that 22 psylloid species were recorded on citrus. In comparison, nine psylloid species were found on Vachellia spp. and unidentified plant species separately, whereas six, three and two psylloid species were recorded on marula, Ficus sp. and mopane, respectively. The abundance, richness and community structure of psylloids differed significantly between the collection methods, provinces and among plant species. The rbcLaF/R primer pair amplified all citrus leaf gDNA samples, producing amplicons of the targeted 530-bp size. The PCR analysis of 11 psylloid species showed that the rbcLaF/R primer pair amplified plant DNA, with PCR-amplified plant DNA samples producing amplicons between 500-bp and 750-bp in the gut contents of five psyllid species: Diaphorina punctulata, Diaphorina virgata, Diaphorina zebrana, Euryconus sp. and Trioza erytreae. However, the targeted 530-bp plant DNA region was only amplified from the gut contents of Euryconus sp. and Diaphorina punctulata. This study documented psylloid diversity and community structure within commercial citrus environments. The findings indicate that the community of psylloids was diverse in citrus environments, with yellow sticky traps being more effective in monitoring different psyllid species within these environments. Furthermore, the PCR analysis detected citrus DNA in the gut contents of Euryconus sp. and Diaphorina punctulata, suggesting that they could be nibbling on citrus when their specific or main host-plants adjacent to citrus orchards are depleted. However, these insects do not lay their eggs or complete their life cycle on citrus, further confirming that citrus is not their host-plant. Thus, further studies, including Sanger sequencing of PCR-amplified plant DNA, are recommended to confirm the ingested plant species, and host-specific testing including infection trials needs to be conducted. , Thesis (MSc) -- Faculty of Science, Zoology and Entomology, 2024
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  • Date Issued: 2024-10-11

An evaluation study of the climate change adaptation plans for a provincial conservation authority in South Africa

  • Authors: Van den Berg-McGregor, Eleanor Charmell
  • Date: 2024-10-11
  • Subjects: Climate change adaptation , Climatic changes South Africa , Ecosystem-based adaptation , Resilience (Ecology) , Protected areas South Africa
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/461930 , vital:76252
  • Description: While there are natural changes in climate over time, the climate change phenomenon of global warming that the Earth is currently experiencing is human-induced. The impact of human-induced climate change has led to unprecedented global warming and has become evident as there have been increases in the frequency and intensity of extreme weather events such as inter alia, heatwaves, droughts and floods. This climate change trajectory poses a risk to the Earth’s ability to continue providing sustainable ecosystem services necessary to sustain life on Earth. Therefore, considering the risks and impacts of climate change, there is a need to strengthen the global response to the threat of climate change, and hence, there is a need for climate change adaptation (CCA). Some benefits of CCA include the reduction of risks to nature and people, biodiversity conservation, food security, livelihoods and human well-being. Through a CCA lens within the biodiversity and conservation sector, underpinned by Resilience Theory, this research study sets out to identify and evaluate the CCA plans of a provincial conservation authority. By reviewing the current literature for CCA, the insights gained allowed for the emergence of key characteristics for good CCA in the biodiversity and conservation sector, and the evaluation of CapeNature’s (a provincial conservation authority situated in the Westen Cape of South Africa) CCA plans against these key characteristics that emerged for CCA and resilience planning in protected areas and ecosystems. Qualitative data was gathered via focus groups and individual semi-structured interviews with seven key knowledge holders of CapeNature’s CCA planning processes, plans and management approaches, and through document analysis of the entity’s CCA plans, whereafter it was evaluated against the key characteristics. Challenges towards CCA and opportunities that can be explored for CCA were identified as well. This research study has revealed that CapeNature does not have a single all-encompassing CCA plan but has various CCA approaches that consider the key characteristics necessary for good CCA. However, the entity faces various challenges regarding its intention to implement these approaches over the long term. Challenges ranged from a fragmented approach to CCA to compromised capacity and capability to implement their CCA plans over time. A recurring challenge was the lack of financial resources, and this, combined with the entity’s current inability to secure sustainable financing, was emphasised as the key factor to be addressed towards facilitating the success of the entity’s CCA plans. It also emerged that CCA approaches are interdependent and linked as in various instances, when one key CCA characteristic was compromised, it had a detrimental effect on other CCA approaches. The study concludes by making recommendations to enhance CapeNature’s CCA and resilience planning, noting that these may be of relevance to other conservation agencies as well. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
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  • Date Issued: 2024-10-11

An exploration of the influence of gender dynamics on the experience of NGO staff members in Makhanda

  • Authors: Hove, Taguma Florence
  • Date: 2024-10-11
  • Subjects: Gender inequality , Non-governmental organizations South Africa Makhanda , Black feminism , Corporate culture South Africa Makhanda , Gender stereotype , Sex role
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/466139 , vital:76700
  • Description: This research explores gender dynamics within non-governmental organisations (NGOs) and examines whether, and to what extent women in the NGO sector perceive gender dynamics as playing instrumental roles in NGO organisational processes and structures. In conjunction with this, this research aims to explore the relationship between gender stereotypes and career progression. Black feminism and postcolonial feminism will be implemented as theoretical frameworks to explore how social or gender, age, race, and class interact with the organisational process of NGOs. The concepts of intersectionality and subjectivity are useful in understanding how interactions between race, class, and gender play a role in the subjective experiences of women of all backgrounds in post-apartheid South Africa. A postcolonial feminist approach focuses on the representation of African women, and allows an exploration of the knowledge of South African women within NGOs that will provide more perspectives to organisational studies. Traditional perspectives of gender stereotypes are widespread, but several respondents are indifferent to gender stereotypes while some of them feel that they are non-existent. The findings indicate that gender stereotypes continue to exist with forward movements in social progress, where progress might be stalled because of ingrained patriarchal norms, making it difficult to eradicate gender inequality. The findings from the research also suggest that there are tensions and contradictions involved when it comes to how female NGO staff members perceive gender discrimination, providing nuance to existing research. This research acknowledges the period of transition that society is in and recognises how complexities emerge. The findings capture the present state of gender identity, and applying an intersectional approach has indicated that other factors such as race, ethnicity and age take precedence. The research also recognises the importance of tracking and responding to changing societal attitudes in times of transition. Finally, the research also contributes to a broader understanding of the perceptions of gender identity and equality and ensures that discussions on patriarchy do not depend on established discussions that present reality in a stark way that does not leave space for nuance. , Thesis (MSocSci) -- Faculty of Humanities, Sociology, 2024
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  • Date Issued: 2024-10-11

An exploratory study of the benefits of reading clubs for learners in English First Additional Language classrooms

  • Authors: Mbebe, Xolela Desmond
  • Date: 2024-10-11
  • Subjects: English language Study and teaching (Secondary) South Africa , Second language acquisition , Group reading , Reading comprehension , Exploratory research
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/463724 , vital:76435
  • Description: The study explored how reading clubs inculcate the love of reading in Komani, Eastern Cape Province, South Africa. Reports indicate that learners at secondary schools do not understand the vocabulary used in comprehension passages. They need exposure to a variety of texts to promote reading comprehension. This study is situated in the interpretive paradigm. The participants were three educators with 24 learners in the reading clubs. Vygotsky’s Socio-Cultural Theory was the theoretical framework to explore how reading clubs promote the love of reading. Data was analysed by using an inductive, thematic approach. The findings indicate that the reading clubs instilled the love of reading among the learners, improving their comprehension skills. The other benefits were that reading clubs are a source of pleasure, instil the culture of reading, and develop the learners’ confidence. The implications of the findings of the study are that reading boosted thinking, reading skills, fluency, knowledge, writing, and vocabulary use. Reading clubs were beneficial to both teachers and learners. Teachers improved their practice and could determine, through oral and written reviews, whether reading took place during the silent reading sessions. Involvement in reading clubs had social benefits for learners. , Thesis (MEd) -- Faculty of Education, Institute for the Study of Englishes of Africa, 2024
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  • Date Issued: 2024-10-11

An investigation into the causes and effect of rising public debt in South Africa, 2009-2019

  • Authors: Mzumala, Mirriam
  • Date: 2024-10-11
  • Subjects: Debts, Public South Africa , South Africa Economic conditions , Global Financial Crisis, 2008-2009 , Expenditures, Public , Economic development South Africa
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/461918 , vital:76251
  • Description: This study delves into the intricate factors contributing to the rising public debt in South Africa between 2009 and 2019, while also scrutinising the efficacy of public debt expenditure during this period. By examining data sourced from the SA National Treasury of South Africa and the South African Reserve Bank (SARB), the research endeavours to elucidate the underlying causes behind the burgeoning public debt and assess the impact of expenditure patterns on economic outcomes. The global financial crisis of 2008/2009 marked a pivotal juncture for South Africa's economy, precipitating a series of fiscal challenges that reverberated throughout the subsequent decade. Against this backdrop, this study embarks on a dual mission: firstly, to decipher the drivers underpinning the surge in public debt, and secondly, to gauge the efficacy of public expenditure vis-à-vis economic growth and development objectives. From 2009 to 2019, fiscal analysis shows a clear pattern of growing budget deficits, with government spending surpassing revenue growth. South Africa's fiscal policy has heavily favoured deficit spending, relying on debt to cover revenue shortfalls and maintain expenditure growth. Most government spending goes towards current payments and social transfers, leaving little for capital formation. Despite the National Development Plan's emphasis on investing in productive assets, both public and private sector investments have consistently fallen below targets, hindering significant contributions to economic growth. The rising public debt in South Africa stems from numerous factors, including excessive spending on unproductive areas like government compensation and social transfers, alongside high borrowing costs. This consumption-focused economic approach, coupled with insufficient investment in productive assets, has hindered South Africa's economic progress compared to global counterparts. Given these challenges, it is crucial to shift fiscal priorities towards strategies focused on investment-led growth. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2024
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  • Date Issued: 2024-10-11

An investigation into the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of Tulbaghia violacea collected from the Eastern Cape and Gauteng Province

  • Authors: Kader, Tasmeera
  • Date: 2024-10-11
  • Subjects: Tulbaghia violacea , Phytochemicals , Alliaceae Geographical distribution , Diabetes , Alzheimer's disease
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/461819 , vital:76242
  • Description: Introduction: The number of communicable and non-communicable diseases continues to rise and has become more prevalent. While drugs exist to manage and/ or treat majority of the communicable and non-communicable diseases, the rise in disease prevalence puts pressure on researchers to find new drug molecules to treat and manage these ailments. Traditional medicine refers to the knowledge, skills and practices which are based on the beliefs and experiences indigenous to cultures and is used to maintain health. Most of the research into traditional medicine focuses on the medicinal plants used. Medicinal plants are any plants in which one or more of its organs contain substances which are used for therapeutic purposes or for the synthesis of drugs. Tulbaghia violacea is a monocotyledonous genus of herbaceous perennial bulbs which is native to Africa and can be readily found throughout South Africa. It is popular for its antimicrobial, antifungal, anticoagulant, antioxidant and anticancer properties. It has been that ecological factors influence the composition and quantity of phytochemicals present in a plant. Aim of the study: The aim of the study was to investigate the impact of geographical location on the phytochemical composition, pharmacological and toxicological activities of T. violacea collected from the Eastern Cape and Gauteng Province. Methods: The leaves of T. violacea were collected from the Eastern Cape and Gauteng Province. The leaves were dried and extracted using serial maceration with solvents hexane, acetone and methanol. The resulting extracts were subjected to qualitative preliminary phytochemical analysis and a quantitative total phenol content test was carried out using gallic acid as the standard. Thin layer chromatography (TLC) was performed to identify classes of compounds present in T. violacea. xix Antioxidant activity of T. violacea was determined qualitatively using a dot-plot and quantitatively using a DPPH radical scavenging activity assay. Ascorbic acid was used as the standard. Anti-diabetic properties of T. violacea were assessed using an α- amylase inhibition assay and an α- glucosidase inhibition assay. Acarbose was used as the standard for these assays. The anti-Alzheimer properties of T. violacea leaf extracts was determined using and acetylcholinesterase (AChE) inhibition assay. Donepezil was used as the standard for this assay. The DPPH radical scavenging activity, the α- amylase inhibition assay, the α- glucosidase inhibition assay and the AChE inhibition assay was combined with linear regression to determine the IC50 values of the T. violacea extracts and the standards. Statistical analysis was conducted to determine any differences between the plant samples and the standards as well as any differences between the EC and GP sample. Results: The results of the qualitative phytochemical analysis revealed the presence of saponins, flavonoids, tannins, alkaloids, steroids, cardiac glycosides and phenolic compounds present in T. violacea collected from EC and GP. However, their presence in the samples were different based on where the plant was cultivated. The results of the total phenolic content test, revealed that the hexane, acetone and methanol extracts of T. violacea contained phenolic compounds with the highest quantity of phenolic compounds being present in the methanol extracts. Significant statistical difference in total phenolic content between the EC and GP samples were seen for the hexane and methanol extracts. The results of the TLC revealed the presence of multiple bands which confirmed the presence of multiple phytochemicals in T. violacea. All of the extracts of T. violacea from EC and GP, showed antioxidant activity using both the dot-plot and the DPPH radical scavenging activity assay. The highest DPPH radical scavenging activity was seen by the hexane extract of the EC sample of T. violacea. The results showed significant statistical difference between the DPPH radical scavenging activity of the EC and GP samples. , Thesis (Msc (Pharmacy)) -- Faculty of Pharmacy, Pharmacy, 2024
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  • Date Issued: 2024-10-11

An investigation of geospatial technologies in precision agriculture: a case study on a citrus orchard in the Eastern Cape

  • Authors: Nish, Declan Mark
  • Date: 2024-10-11
  • Subjects: Geospatial technology , Agricultural innovations , Precision farming South Africa Eastern Cape , Citrus orchard , Citrus fruit industry , Drone aircraft , Remote sensing
  • Language: English
  • Type: Academic theses , Master's theses , text
  • Identifier: http://hdl.handle.net/10962/465080 , vital:76571
  • Description: Citrus production is an input-intensive farming practice that carries a high cost of production. A multitude of both local and global factors continue to put pressure on farmers to produce enough food for local consumption as well as international exports. Despite these challenges production and exports continue to increase, fighting to meet the growing rise in global demand for citrus (Genis, 2018). Growers are continuously in search of anything that may provide them with the ‘edge’ or an advantage to overcoming some of these challenges (Jupp, 2018). One way in which these issues could be addressed is the use of precision agriculture (PA). Precision agriculture, particularly that of commercial, Unmanned Aerial Vehicle (UAV) based PA, provides growers with solutions to these issues in the form of high quality, near real-time data, and provides access and benefits from technology driven agriculture to growers at all levels (Sishodia et al. 2020). The aim of this research therefore was to investigate the potential of high resolution, multi-spectral UAV, and satellite imagery to help citrus farmers manage their inputs better, save costs and increase their yields in a sustainable manner. Supervised image classification using a support vector machine (SVM) was applied to map and classify a citrus farm in the Eastern Cape. The approach aided the identification of Phytophthora spp in the section of interest and implies that remotely sensed data can be used to detect changes in citrus health. Guidelines for applying geospatial technologies at farm level were developed to provide a framework for enabling growers to enhance data driven farm management strategies. , Thesis (MSc) -- Faculty of Science, Geography, 2024
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  • Date Issued: 2024-10-11
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