List of Titles

Negotiating family planning messages among Malawian men: A case study of vasectomy messages aimed at men in the Dedza and Karonga districts of Malawi

- Ntaba, Jolly Maxwell

Authors: Ntaba, Jolly Maxwell
Date: 2020
Subjects: Social marketing -- Malawi , Vasectomy -- Social aspects -- Malawi , Malawians -- Attitudes , Men -- Malawi -- Attitudes , Men -- Conduct of life -- Malawi , Men -- Sexual behavior -- Malawi , Masculinity -- Malawi , Reproductive health in mass media -- Malawi , Reproductive health services -- Malawi
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167200 , vital:41446
Description: Since the 1990s, vasectomy, the principal non-barrier method of contraception offered to men, has been vigorously promoted in Malawi, as a safe, effective and inexpensive form of birth control. Despite this marketing, the method has been chosen by only an estimated 0.01% of men in Malawi. This compares to about 11% of contraceptive using Malawian women, who have opted for tubal ligation, a more expensive and hazardous surgical procedure. Previous studies into this low uptake of vasectomy among men in Malawi, and other studies that have explored why no African country currently has a vasectomy rate of more than 1% of men, implicate cultural beliefs and traditional social practices among the key barriers to the diffusion of this particular innovation i.e. this method of contraception. Campaigns share new information in the hope that they will shift their audiences’ knowledge, and lead to changes in attitudes and practices, including the uptake of vasectomy. Social Marketing campaigns, even when they set out to explicitly accommodate these beliefs and challenge particular practices in order to promote various methods of contraception, are often inadequately conceived and sometimes poorly executed. Drawing on well-established theoretical perspectives developed by Cultural Studies scholars, including Reception Analysis and Thematic Analysis, this study investigates how men in two purposively selected districts of Karonga and Dedza in Malawi, interpret Social Marketing messages encouraging them to undergo vasectomies. The study examines key media texts and the nature of the involvement of a group of peer educators, dubbed ‘male champions’ in a 2017-2018 campaign by one of the leading Malawian providers of family planning services, the NGO Banja La Mtsogolo (BLM), to promote vasectomy. This is a purely qualitative case study that seeks to understand why these often-well-resourced campaigns have so little impact on the behaviour change they hope to inspire. Through individual interviews with the campaign’s designers, implementers, peer educators, focus group discussions with the campaign’s audiences, a close reading of texts used in the campaign, and observation, this study explores the circuits of communication and culture, through mechanisms of resonance, disconnection and even cognitive dissonance between the ‘encoders’ of the family planning messages and the decoders i.e. the intended audiences of the campaign. The study argues that as a result of several ‘modernist’ assumptions and outlooks, the campaign was unable to fully grasp the complex and contextually nuanced socio-cultural practices that factor into consideration of the campaign’s messages and the non-adoption of the proposed vasectomy method. The study further reveals, as many other studies have also observed, that the interpretation of the text promoting vasectomy is a complex process that is significantly shaped by the worldviews and lived experiences of the audiences. These views, as this study explores, are often complex and contradictory, interfacing aspirations of modernity with deeply held ‘traditional’ beliefs and practices. Although the campaigns are effective at transferring knowledge – it finds most targeted men have a relatively good understanding of the method and its efficacy – their prevailing socio-cultural attitudes and dispositions provide a strong countervailing discourse to the preferred reading of the campaign messages. This discourse exhorts having children, or the capacity to have children, even after a man has had several before, in current or previous marriages, or even in old age, as desirable and ‘rational’. The study therefore proposes, arising out of this detailed ethnographic research, a revised approach that argues that several social and cultural ‘vectors’ or ‘spheres of influence' need to be considered in new ways, in order to develop meaningful interventions in the promotion of vasectomy. This includes specific strategies to understand and challenge: 1. The enduring power of social stigma and scorn, and the notion of social shame. 2. The deep interplay between fertility and having children to notions of marriage, even in second or third marriages, and the interplay with perceptions of economic ‘value’ of children in the domestic political economy of marriage. 3. The embedded nature of provable fertility to notions of manhood. 4. The complex and nuanced involvement, at many levels, of broader social/family structures/personages in ‘personal’ decisions. 5. Forms of ‘hyperbolic discounting’, i.e. the calculating of precarious futures in various scenarios and its impact on current shorter-term calculations and gratifications. 6. Unusually high rates of infidelity in marriage, and seemingly low levels of trust in many partnerships. 7. The key role of interpersonal communication, i.e. the face-to-face elements of what are usually media-centric Social Marketing campaigns. The study recommends a more layered and nuanced approach to the promotion of vasectomy, propelled by a deeper understanding of these kinds of contexts and the interpretive power of the intended audience, as well as more nuanced segmentation of audiences, and more judicious use of peer-educators to support and deepen the mass media components of these communication campaigns.
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Date Issued: 2020

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NFComms: A synchronous communication framework for the CPU-NFP heterogeneous system

- Pennefather, Sean

Authors: Pennefather, Sean
Date: 2020
Subjects: Network processors , Computer programming , Parallel processing (Electronic computers) , Netronome
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/144181 , vital:38318
Description: This work explores the viability of using a Network Flow Processor (NFP), developed by Netronome, as a coprocessor for the construction of a CPU-NFP heterogeneous platform in the domain of general processing. When considering heterogeneous platforms involving architectures like the NFP, the communication framework provided is typically represented as virtual network interfaces and is thus not suitable for generic communication. To enable a CPU-NFP heterogeneous platform for use in the domain of general computing, a suitable generic communication framework is required. A feasibility study for a suitable communication medium between the two candidate architectures showed that a generic framework that conforms to the mechanisms dictated by Communicating Sequential Processes is achievable. The resulting NFComms framework, which facilitates inter- and intra-architecture communication through the use of synchronous message passing, supports up to 16 unidirectional channels and includes queuing mechanisms for transparently supporting concurrent streams exceeding the channel count. The framework has a minimum latency of between 15.5 μs and 18 μs per synchronous transaction and can sustain a peak throughput of up to 30 Gbit/s. The framework also supports a runtime for interacting with the Go programming language, allowing user-space processes to subscribe channels to the framework for interacting with processes executing on the NFP. The viability of utilising a heterogeneous CPU-NFP system for use in the domain of general and network computing was explored by introducing a set of problems or applications spanning general computing, and network processing. These were implemented on the heterogeneous architecture and benchmarked against equivalent CPU-only and CPU/GPU solutions. The results recorded were used to form an opinion on the viability of using an NFP for general processing. It is the author’s opinion that, beyond very specific use cases, it appears that the NFP-400 is not currently a viable solution as a coprocessor in the field of general computing. This does not mean that the proposed framework or the concept of a heterogeneous CPU-NFP system should be discarded as such a system does have acceptable use in the fields of network and stream processing. Additionally, when comparing the recorded limitations to those seen during the early stages of general purpose GPU development, it is clear that general processing on the NFP is currently in a similar state.
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Date Issued: 2020

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Non-marital fertility in South Africa: trends, determinants and implications

- Kara, Reesha

Authors: Kara, Reesha
Date: 2020
Subjects: Fertility, Human -- South Africa , Child rearing -- South Africa , Parenting -- South Africa , Motherhood -- South Africa
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/165620 , vital:41264
Description: Background: Non-martial fertility is traditionally associated with teenage pregnancy however international and South African literature has detailed increases in the number of adult women who are having children outside of a marriage. South African literature on non-marital fertility is sparse as it lacks a national overview of the trends and determinants of non-marital fertility among women aged 30 and older. The aim of this study was to present a national overview of non-marital fertility among women aged 30 and older. South African’s attitudes to and opinions of non-marital fertility were also investigated, and the lived realities of older mothers were explored. Methods: A mixed-methods research design was employed where the General Household Survey, National Income Dynamics Study and the South African Social Attitudes Survey were the main data sources. Using these data sets, descriptive and inferential statistics were computed using Stata. Using purposive and snowball sampling, four never-married older mothers (NMOMs) from KwaZulu-Natal (Durban) were identified as research participants. The in-depth life histories of these women were collected through face-to- face semi-structured interviews. Results: The results show an 18.43% increase in never-married mothers aged 15- 49 between 2002 and 2017 and interestingly, this increase is not necessarily driven by older mothers (30-49). NMOMs belonged to households with a lower average per capita total monthly household income (R1873.91) compared to all mothers aged 30-49 (R3428.76). NMOMs were also more likely to live in female-headed households (89.52%), to be household heads (64.22%) and to live in traditional areas (35.72%). Between 2002 and 2017, there was a 76.76% increase in mothers (aged 30-49) who were never married and a 7.74% decrease in those who were married, indicating a change in the marital profile of mothers. Despite this national increase in non-marital fertility, South African’s believe that premarital sexual activity is wrong, and that childbearing should take place within a marriage. Similar sentiments were echoed in the in-depth life histories as being the sole breadwinner and primary caregiver, the research participants experienced challenges as single mothers. Conclusion and recommendations: The study has found that there has been an increase in non-marital fertility in South Africa between 2002 and 2017 and that there is an economic element to non-marital fertility in the country. Additional research into non-marital fertility at a national level is recommended with a focus on all women aged 15-49.
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Date Issued: 2020

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Not Yet Uhuru! Attuning to, re-imagining and regenerating transgressive decolonial pedagogical praxis across times Khapa(ring) the rising cultures of change drivers in contemporary South Africa

- Kulundu-Bolus, Injairu

Authors: Kulundu-Bolus, Injairu
Date: 2020
Subjects: Not Yet Uhuru (Arts Project) , Anti-imperialist movements -- South Africa , Education -- Social aspects -- South Africa , Social change -- South Africa , Education -- Philosophy -- South Africa , Arts and society -- South Africa
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/166081 , vital:41327 , 10.21504/10962/166081
Description: The “Not yet Uhuru!” project positions itself as emancipatory African research in motion. It is a regenerative project that responds to the concern that whilst dominant discourses can articulate what African states, societies and economies are not, we still know very little about what they actually are. This is a particularly important gap in how research on Africa is conceptualised, especially as it pertains to apprehending the futures that the majority of young people on the continent are instinctively leading themselves to (Mbembe, 2001, p.9). The project seeks to forgo youth development strategies that act as a form of containment by prescribing normative aspects of citizenship on young leaders in ways that stifle the transgressive impulses they have reason to value (Kelley in Tuck and Yang, 2014, p.89). The study traces rising cultures in transgressive decolonial pedagogical praxis across times, as a way of “khapa(ring)” or accompanying the contemporary questions that Change Drivers in South Africa hold at the edge of their praxis. The study co-conspired with 21 Change Drivers in South Africa who were interested in regenerating and re-imagining what transgressive decolonial praxis could be in these times based on their experiences and learnings. Residential art-based workshops that explored each co-conspirator’s offerings on the subject were distilled through the medium of film. These in turn were analysed using an “ethics of attunement” that produced songs as a reflexive pedagogical tool (Lispari, 2014, p.176). Sharing the resonate echoes of their praxis through song created another iterative reflection on their praxis two years after their initial offerings. As a way of weaving together the findings with a historical perspective, the resonant praxis of Change Drivers was put into conversation with three unconventional reviews that trace impulses around transgressive decolonial pedagogical praxis through fictional texts, political theory, poetry and intergenerational analysis, in order to surface resonant themes in praxis that echo across different times in history. This methodology sought to engage the question of the archive in pluriversal ways that appealed to different sensibilities, including the imaginative and hermeneutical, the traditionally analytical as well as the gifts of the lyrical and the erotic as different conceptual threads needed to resource the study. The reviews additionally spanned periods in the history of the continent that hold questions around precolonial and nascent colonial encounters, efforts to transgress within the liberatory movements and the intergenerational transmissions embedded in women and queer people’s struggles. The themes that coalesced across times were leveraged into capsules of rising cultures that form an experimental nexus for the practice of transgressive decolonial pedagogical praxis that is already underway. These rising cultures were conceptualised as meditations on what it means to live into a vision of home built on the explorations of a paradigm of peace, humanness, pluriversality and decolonial love for those like and unlike us that strive for freedom on this continent (Dlala, 2017, p.52; Ndlovu- Gatsheni, 2013, p.142; Gqola, 2017, pp.197, 199). The rising ultures were reconciled through the creation of a litany that chronicles different refrains in transgressive decolonial pedagogical praxis in contemporary times. The litany is a tool that charts particular experiences that are surfacing as symptomatic. It seeks to generously surface the contradictions that we are collectively starting to see past, whilst acknowledging the tensions that we need to straddle, integrate and navigate towards greater synthesis. The litany is an honest way of acknowledging the glimpses gained of who we are in this present moment, while we continually challenge ourselves to open up to questions about what it means to grapple towards decolonial futures. This stance has influenced my role as an educator to unconditionally embrace movements that already underway, and reflect these back to those that I am conspiring with in ways that promote an ethic of care, solidarity and critical engagement. The study celebrates what is possible when we do not theorise ourselves away from the questions embedded in our current praxis. This is an ethic that chooses to stay close to the phenomena arriving at present, whilst acknowledging the historical experiences that echo it as a collective pulse for meaningful experimentation and praxis. The study believes by being faithful to ways of amplifying, integrating and reflecting what has been emerging for us over time, we build our capacity to better respond with an ethic centred on transgressive decolonial pedagogical praxis. This is the kind of accompaniment and care that Change Drivers across the continent deserve as they make the way towards a future worthy of their longing (Rushdie, 1999).
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Date Issued: 2020

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Passphrase and keystroke dynamics authentication: security and usability

- Bhana, Bhaveer

Authors: Bhana, Bhaveer
Date: 2020
Subjects: Computer security -- Management , Computers -- Access control -- Codewords , Computers -- Access control -- Keystroke timing authentication , Entropy (Information theory)
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/146663 , vital:38546
Description: It was found that employees spend a total 2.25 days within a 60 day period on password related activities. Another study found that over 85 days an average user will create 25 accounts with an average of 6.5 unique passwords. These numbers are expected to increase over time as more systems become available. In addition, the use of 6.5 unique passwords highlight that passwords are being reused which creates security concerns as multiple systems will be accessible by an unauthorised party if one of these passwords is leaked. Current user authentication solutions either increase security or usability. When security increases, usability decreases, or vice versa. To add to this, stringent security protocols encourage unsecure behaviours by the user such as writing the password down on a piece of paper to remember it. It was found that passphrases require less cognitive effort than passwords and because passphrases are stronger than passwords, they don’t need to be changed as frequently as passwords. This study aimed to assess a two-tier user authentication solution that increases security and usability. The proposed solution uses passphrases in conjunction with keystroke dynamics to address this research problem. The design science research approach was used to guide this study. The study’s theoretical foundation includes three theories. The Shannon entropy formula was used to calculate the strength of passwords, passphrases and keystroke dynamics. The chunking theory assisted in assessing password and passphrase memorisation issues and the keystroke-level model was used to assess password and passphrase typing issues. Two primary data collection methods were used to evaluate the findings and to ensure that gaps in the research were filled. A login assessment experiment collected data on user authentication and user-system interaction for passwords and passphrases. Plus, an expert review was conducted to verify findings and assess the research artefact in the form of a model. The model can be used to assist with the implementation of a two-tier user authentication solution which involves passphrases and keystroke dynamics. There are a number of components that need to be considered to realise the benefits of this solution and ensure successful implementation.
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Date Issued: 2020

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Performance, functionalism and form in Ịzọn oral poety

- Armstrong, Imomotimi

Authors: Armstrong, Imomotimi
Date: 2020
Subjects: Ijo (African people , Ijo language , Folk poetry, Ijo , Folk poetry -- Nigeria
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/140641 , vital:37906
Description: Since the publication of Ruth Finnegan’s influential Oral Literature in Africa, way back in 1970, scholars have been paying earnest attention to oral traditions on the African continent. That seminal book pointed out to Africanist scholars the need to urgently collect and document the oral literatures of their various ethnic groups before they die out. However, it is the verbal arts of the major ethnic groups on the continent that very often benefit from this collection and documentation, as it were. Therefore, this study sought to examine the oral poetry of the Ịzọn, a minority ethnic nationality, located in the oil-rich Niger Delta region of Nigeria. The study employed unstructured interviews and participant observations to collect the data for the research. The transcribed and translated data was examined through three eclectic theories to the study of folklore: Russian formalism, performance and functionalism. The study found out that Ịzọn oral poetry is a combination of songs and one person’s praise chants. Moreover, it revealed that praise chanting is a recent practice amongst the Ịzọn that was introduced into Ịzọnland by Chief Adolphus Munamuna from the Yoruba of southwestern Nigeria. Furthermore, the study established that oral poetry plays important roles amongst the people. Besides, it ascertained that the performance of some sub-categories of the poetry is highly dramatic and theatrical. It also discovered that stylistic techniques such as formula, parallelism, proverb, ideophone, praise title, metaphor, repetition, alliteration, assonance, vowel lengthening, amongst others, give the poetry the quality of “literariness.” In addition, the study found out that the poetry, like oral poetry in other ethnic groups, demonstrates the three qualities of change, adaptability and survival. The study has contributed to existing scholarship on African oral traditions in the sense of collecting, documenting and generating awareness on Ịzọn oral poetry, most importantly pointing out the existence of praise chanting amongst a people who had no such culture and the conditions that gave rise to that practice.
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Date Issued: 2020

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Post release evaluation of the distribution and efficacy of Eccritotarsus catarinensis and Eccritotarsus eichhorniae on Pontederia crassipes in South Africa

- Maseko, Zolile

Authors: Maseko, Zolile
Date: 2020
Subjects: Water hyacinth -- Biological control -- South Africa , Weeds -- Biological control -- South Africa , Miridae -- South Africa , Insects as biological pest control agents -- South Africa
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/143046 , vital:38196
Description: Biological control involves the release of new species into the environment and therefore, needs to be carefully monitored through post-release assessments which have been largely neglected in the science. Post-release evaluations of biological control programmes reveal whether the control agent has established and if it impacts weed demography, while cost-benefit analyses require a different set of data that show the magnitude on return on investment. The biological control effort on Pontederia crassipes in South Africa uses, amongst others, two species of mirid, Eccritotarsus catarinensis and E. eichhorniae. Initially, they were released as a single species, but were recently divided using molecular techniques. Eccritotarsus catarinensis was released in 1999, and E. eichhorniae in 2007. After many releases over two decades, there was need to assess where each species was established in the country. Molecular techniques proved to be valuable in identifying the two species as they are morphologically indistinguishable in the field. Therefore, molecular techniques should be routinely used for screening biocontrol agents, whether new or as re-introductions. Annual surveys of the mirid release sites around South Africa were undertaken between 2016 and 2019. At each site both insect and plant parameters were measured. Only E. catarinensis is established in the field in South Africa despite the multiple releases of E. eichhorniae at over 70 sites across the country, and E. catarinensis has established at only 22 of the 45 release sites accessed during this study. This thesis tested climate, interaction with other agents already on P. crassipes, and direct competition between the two mirid species as reasons for the lack of establishment of E. eichhorniae. The results of the country-wide surveys showed that climate and water trophic status were the major determinants in the establishment of E. catarinensis. Most of the establishment was recorded in the warmer regions of the country, however, a few populations of the mirid also established in cooler areas, thus demonstrating a degree of thermal plasticity, and possible microclimates as the mirids persisted at sites shaded by riparian vegetation. Stochastic events such as active herbicide campaigns, winter frosts, droughts and floods were responsible for the absence of the mirid at some sites. At some of the eutrophic sites, despite the abundance of E. catarinensis, plants still proliferated as the water trophic status facilitated plant growth, thus, plants were able to compensate for the damage inflicted by the mirid. A more intensive, monthly, post-release evaluation was conducted on the Kubusi River, Eastern Cape Province between 2016 and 2019. This is regarded as one of the cooler water hyacinth sites. Populations of biological control agents at this site fluctuated seasonally. At this site, cold winters caused frosting of the leaves of P. crassipes with the exception of plants growing under overhanging vegetation that provided a refuge for the mirid. But, cool temperatures in the winter months (May to August) severely reduced the populations of E. catarinensis that required a long recovery phase in spring. The consequence of this was that the plants grew unchecked from the onset of the growing season forming dense mats. Of the four agents at the Kubusi River site, Eccritotarsus catarinensis recovered slowest after winter, with lag phases ranging from two months to several months of the three-year period. The release of a suite of agents has implications on the agents themselves, where interactions between the agents can be important. Interactions between pairs and even multiple agents can have implications for biocontrol, where agents are either complimentary or interfere with each other. In this case, because E. catarinensis recovered the slowest of the four agents at the site, plants were of a poor quality by mid-summer resulting in low mirid populations. Competition in weed biological control could be expected to be strongest between pairs of agents that share the same niche, and this could be the reason why E. eichhorniae failed to establish at sites where E. catarinensis had already been established for several years. When the two mirids were combined in manipulated trials in a polytunnel, populations were lower compared to when the two mirids occurred separately. Under warm conditions, it is likely that E. eichhorniae would be the superior agent compared to E. catarinensis. The evaluations discussed in this thesis highlighted gaps in agent release methodology in multispecies settings, as well as the need for strategic augmentation pre- and post-winter. It is important to release agents that will complement each other rather than compete, therefore, when releasing agents in a multispecies setting, niche differentiation needs to be considered. Here it is concluded that the best practice for dealing with the mirids is that they should be released individually, and at sites that have no other biological control agents in order to ultimately assess their efficacy. Landscape level, long-term monitoring of biological control programmes shows the impact of the control programme at a broader scale and, are far more informative than short-term studies and at fewer sites. Long-term post-release evaluations should be mandatory in biological control programmes. Furthermore, these assessments will help develop new strategies or improve on existing ones, thus achieve greater success in control.
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Date Issued: 2020

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Post-apartheid nostalgia and the future of the black visual archive

- Nsele, Zamansele Nsikakazi Busisiwe

Authors: Nsele, Zamansele Nsikakazi Busisiwe
Date: 2020
Subjects: Nostalgia in art , Memory in art , Africa -- In art , Africans in art , Fanon, Frantz, 1925-1961. Peau noire, masques blancs. English , South Africa -- In art , Black people in art
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167177 , vital:41444
Description: The implications of nostalgia often strike a discordant note in post-apartheid discourse and this has opened up critical possibilities for research scholarship. For instance, Jacob Dlamini’s memoir Native Nostalgia entered the discursive fray in 2009, and it was subsequently followed by Derek Hook’s psychoanalytical approach in (Post) apartheid Conditions: Psychoanalysis and Social Formation in 2014. Notably, there is not yet a sustained and intensive research focus that has been conducted on post-apartheid forms of nostalgia within the discipline of art history and visual culture. I present this dissertation as a response to this gap. This thesis identifies mainly two competing nostalgias in post-apartheid South Africa. Through the analysis of selected artwork and media imagery, this dissertation critiques the connections of these nostalgias to the representation of the black figure in post-apartheid visual culture and the implications thereof. I argue that nostalgias for an apartheid-colonial-imperialist past operate through erasure and in the sanitisation of memory and as a result they render suffering indiscernible or in a sadomasochistic way consumes suffering as enjoyable. This thesis simultaneously critiques art work and visual representation that responds to South Africa’s nostalgia for the future: a restorative nostalgia that has emerged in the form of “rainbow nationalism”. This is a form of nostalgia that is underpinned by a dogged commitment to triumphalism and as a result erases the ongoing scenes of abjection. I use nostalgia and Afropessimism as analytical frameworks to argue that both real and visual representational forces work in tandem to restrain the future and this, I suggest is fulfilled by the transference of the black body from one state of unfreedom to next, resonating with a cyclical pattern. Frantz Fanon’s (1967) Black Skin White Mask forms the conceptual bedrock of my study, particularly his visual layout of “negrophobogenesis” and colonial temporality, which he describes as a “hellish cycle” or as an “infernal cycle” wherein the past overwhelms the present and ideas of the future.
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Date Issued: 2020

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Quantifying ecosystem restoration recovery and restoration practice following the biological control of invasive alien macrophytes in Southern Africa

- Motitsoe, Samuel Nkopane

Authors: Motitsoe, Samuel Nkopane
Date: 2020
Subjects: Salvinia molesta , Ceratophyllum demersum , Nymphaea mexicana , Invasive plants -- Biological control -- South Africa , Aquatic weeds -- Biological control -- South Africa , Restoration monitoring (Ecology) -- South Africa , Biolotical invasions -- Environmental aspects
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167519 , vital:41488
Description: Invasive alien aquatic plants (IAAP) species are known to have deleterious effects on the freshwater ecosystems they invade. This includes both socio-economic and ecologically important ecosystem goods and services. Thus, IAAP species are declared a serious threat, second only to habitat modification for causing a loss of aquatic biodiversity. Three control methods have been widely applied to control IAAP species invasion globally; mechanical, chemical and biological control. Both mechanical and chemical control methods are considered short-term and expensive, whereas biological control methods are regarded an effective and long-term solution for IAAP species control at the landscape level. But, little is known of the ecological recovery following the biological control of IAAP species, with mechanical control known to have had mixed success and chemical control to have non-targeted effects on aquatic ecosystems, causing harm to wildlife and human well-being. Biological control practitioners measure the success of biological control based on: (1) the biological control agents’ establishment and the negative impacts they impose on the targeted weed; and (2) the weeds biomass reduction and an increase in native macrophytes species. Arguably, measures of biological control success have been subjective and variable across the globe. Although some field studies have demonstrated biological control success to have positive socio-economic returns, there is little literature on ecological benefits. Furthermore, there is limited understanding on ecosystem recovery and possible restoration efforts following the biological control IAAP species, as compared to alien weeds in terrestrial and riparian ecosystems. Thus, this thesis aimed to quantify the ecological recovery i.e. aquatic biodiversity, ecosystem processes and trophic interactions following the management of Salvinia molesta in freshwater ecosystems. The research employed a suite of Before-After Control-Impact mesocosm and field studies to investigate the response of aquatic microalgae, macroinvertebrates and their interactions (food web structure and function) during S. molesta infestation and after mechanical and biological control. The mesocosm experiment (Before invasion, During invasion & After control) showed that both aquatic microalgae and macroinvertebrate diversity indices were reliable biological indicators of S. molesta ecological impacts and recovery following control. The restored treatment (100% S. molesta cover + biological control agents), demonstrated complete aquatic microalgae and macroinvertebrate recovery following biological control, similar to the control treatment (open water), where the degraded/impacted treatment (100% S. molesta cover with no biological control agents) showed a drastic decline in aquatic biodiversity and a complete shift in aquatic biota assemblage structure. Thus, the biological control effort by Cyrtobagous salviniae, the biological control agent for S. molesta, assisted in the recovery of aquatic biota following successful biological control. The field study (four field sites, two sites controlled mechanically and two biologically) investigated water quality, aquatic biodiversity and community trophic interactions (aquatic food web) “before and after” S. molesta control. The study showed a drastic decline in aquatic biodiversity (with three sites showing no record of aquatic macroinvertebrates, thus no biotic interactions during infestation) and poor water quality due to the shade-effect (light barrier due to floating S. molesta mats on the water surface) during the “before” S. molesta control phase. However, following both mechanical and biological control (“after” S. molesta control phase), there was a significant shift in abiotic and biotic ecosystem characteristics as compared to the “before” S. molesta control phase. Thus, rapid ecosystem recovery was apparent as a result of aquatic microalgae and macroinvertebrates recolonisation. Sites showed a normal functioning ecosystem where improved water quality, increased biodiversity, productivity and trophic interactions, was indicative of the return of biologically and functionally important species which were lost during the “before” S. molesta phase. Although the clear water state showed positive outcomes at Westlake River, these were short lived when the system was dominated by a cosmopolitan submerged Ceratophyllum demersum, and later replaced by a floating-leaved emergent IAAP Nymphaea mexicana. Each state was responsible for a significant shift in both biotic and abiotic characteristics, affirming macrophyte abilities to influence aquatic environments structure and functions. Furthermore, this event showed a clear example of a secondary invasion. Thus, a holistic IAAP species management strategy is necessary to restore previously invaded ecosystems and prevent subsequent secondary invasion and ecosystem degradation. In conclusion, the S. molesta shade-effect like any other free-floating IAAP species, was identified as the main degrading factor and responsible for water quality reduction, loss of aquatic diversity and shift in aquatic biota assemblage structure. Following S. molesta removal (or shade-effect elimination), there was a positive response to aquatic ecosystem species abundance, richness, diversity and community structure. Therefore, in combination, aquatic biota recolonisation rate and increases in biological and functional diversity were instrumental in the recovery of ecosystem structure and functions, following the control of S. molesta. Echoing existing literature, this thesis recommends: (1) IAAP species management programmes (mechanical and/or biological control) should not only aim to control the weed but also focus on ecosystems recovery and possible restoration goals; (2) biological control should be used where appropriate to combat free-floating IAAP species in freshwater ecosystems, followed by active introduction of native macrophyte propagules since they are limited by anthropogenic activities; and (3) more freshwater case studies are needed to add to our understanding of IAAP species management and restoration effort incorporating long-term monitoring.
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Date Issued: 2020

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Reef fish associations with benthic habitats at a remote protected coral reef ecosystem in the Western Indian Ocean-Aldabra Atoll, Seychelles

- Haupt, Philip

Authors: Haupt, Philip
Date: 2020
Subjects: Coral reef ecology -- Aldabra Islands (Seychelles) , Reef fishes -- Aldabra Islands (Seychelles) , Benthic animals -- Aldabra Islands (Seychelles)
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/141629 , vital:37991
Description: The aim of the thesis is to develop an understanding of the associations between reef fish and benthic habitats and assess the modifying effects of environmental processes on these relationships at Aldabra, a pristine atoll in the Western Indian Ocean (WIO). Conducting research in pristine, or reference coral reef ecosystem, removes the impact of direct anthropogenic disturbances and provides essential information on natural ecosystem structure and functioning. Three primary hypotheses were tested: 1) Environmental drivers such as depth and exposure to wave energy determine the spatial distribution of benthic habitats; 2) The reef fish assemblage structure is explained by habitat at multiple scales and modified by the effects of environmental drivers such as depth, wave energy and cyclical temporal drivers such as time and tides; 3) The reef fish assemblage at Aldabra represents a pristine reef fish assemblage, comprising high levels of herbivores and predators. The research focussed on the benthic habitat on the seaward reefs between the shoreline and 50 m depth. The first objective was to characterise the benthic habitats on Aldabra Atoll’s seaward reefs and map their spatial distributions using remotely sensed imagery and ground truthing data. The second was to assess the influence of depth and exposure to wave energy on the distribution of benthic habitats. The third was to identify the most suitable standardised method to survey the reef fish assemblage structure on Aldabra’s, and fourth to determine the effect of tide and time of day on the reef fish assemblage. The fifth objective was to establish the association between reef fish assemblage structure and benthic habitats and to test how species-size influenced the scale of habitat at which the associations were most apparent. Four categories of geomorphic reef zones (reef flats (19.2 km2), top of the forereef slope (7.8 km2), deep forereef slope (11.6 km2), and reef platform (14.3 km2)) were manually delineated following the visual outlines of reef features from satellite imagery. The six broad-scale and twelve fine-scale benthic habitats were mapped using a supervised maximum likelihood classification and the spatial coverage of each determined. The broad-scale habitats were 1) Epilithic algal matrix, 2) Hard and soft (coral, 3) Rubble, 4) Macroalgae, 5) Seagrass and 6) Sand. Similarly, twelve fine-scale benthic habitats were characterised and mapped, for example, Hard coral (19 %) including massive and submassive forms with Millepora and Rhytisma. The broad-scale benthic habitat map had an overall producer accuracy of 54 % and fine-scale habitat map 29 %, which was consistent with studies using similar habitat classification methods. The prevailing wave energy, depth and the directional orientation of coral reefs (aspect) significantly influenced the probability of occurrence of each of the broad-scale benthic habitats, and there was a shift in peak probability of occurrence of all habitat categories to a greater depth with an increase in wave energy. The strong relationship of benthic habitats with depth and wave energy suggests that the distributions of benthic habitats are likely to change with sea-level rise and increased intensity and frequency of storms in future. Overall, 338 fish species from 51 families, including 14 species of elasmobranch were recorded using Baited Remote Underwater Video systems (BRUVs) and unbaited Remote Underwater Video systems (RUVS) from 231 samples. Fish were significantly more abundant when observed using BRUVs (119 ± 7) relative to RUVs (92 ± 7), and the assemblage structures were significantly different between the two sampling methods. Abundance and species richness of generalist carnivores and piscivores were significantly greater in BRUVs, while RUVs recorded significantly greater numbers of herbivores and more species of herbivore and corallivore. The results suggest that BRUVs are better suited when studying predatory fish which may not be detected without bait. However, when surveying a taxonomically and functionally diverse assemblage of fishes at a pristine reef, RUVs may provide a more accurate estimate of natural reef fish assemblage structure. Reef fish assemblages observed using RUVs were significantly different between morning-high-tide, midday-low-tide and evening-high-tide for all trophic groups. However, the reef fish assemblage structure observed using BRUVs was insensitive to change in tide and time of day, which may be explained by the attraction effect of bait dampening the effect of tide and time of day. While RUVs appear better to detect more subtle variations in fish assemblage structure, care needs to be taken when designing research programmes that use RUVs, as the sampling design should account for tide and time of day to avoid misinterpreting the cyclical variation, which may confound results. Reef fish assemblages were significantly different among habitats within geomorphic reef zones, broad-scale and fine-scale habitats. Species turnover rates were significantly different for all Actinopterygii size-class categories between the three scales of habitat. No marked differences in species turnover rates among habitats were detected for the majority of Elasmobranch size-class categories. The strong habitat dependency over various spatial scales indicates that effective conservation of Actinopterygii fish at Aldabra, and elsewhere in similar ecosystems requires protection of representative sets of benthic habitats. However, Elasmobranch conservation requires sufficiently large areas as these species utilise multiple habitats, over multiple scales, which are likely to exceed the confines of Aldabra’s reef.
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Date Issued: 2020

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Resource recovery options in brewery effluent treatment using activated sludge and high rate algal ponds: assessing environmental impacts

- Taylor, Richard Peter

Authors: Taylor, Richard Peter
Date: 2020
Subjects: Sewage -- Purification -- Activated sludge process , Sewage disposal plants , Sewage -- Purification -- Biological treatament , Sewage -- Purification -- Nitrogen removal , Brewery waste , Breweries -- Waste disposal , Microalgae -- Biotechnology , Algal biofuels
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/153746 , vital:39507
Description: Wastewater treatment plants (WWTPs) are designed to clean effluents, but they also consume resources and produce waste. Various treatment technologies allow for the recovery of energy, nutrients and water from effluents turning this waste into products, which increases their sustainability and decreases the impact of WWTPs on the environment. There is a lack of literature which comprehensively compares the treatment performances, environmental impacts and beneficial downstream uses of the biomass generated by high rate algal pond (HRAP) and activated sludge (AS) treatment systems. This thesis aimed to compare (1) effluent treatment performance, (2) emissions and (3) downstream use of algae cultured in HRAP to sludge produced in AS and to obtain data to conduct a life cycle analysis (LCA) to compare the systems. The focus was on adding value to the effluent treatment process, while identifying the associated environmental impacts and contributing to the first ever zero-waste brewery effluent treatment system. Furthermore, these data were used to provide a basis to critically review and contribute to improving the methods used in the LCA of effluent treatment systems; particularly since this was the first wastewater treatment LCA that compared AS and HRAP using data collected from the same temporal and geographic location and from a single effluent stream. The electrical consumption water emission and land application of waste biomass caused the major environmental impacts of both treatment systems. The HRAP had less than 50 % of the electrical energy consumption (0.11±0.01 kW/m3 of effluent treated) compared to the AS system (0.29±0.11 kW/m3) which resulted in the technology having a lower climate change, photochemical oxidant formation, freshwater and marine ecotoxicity and fossil fuel depletion impact. It is imperative to understand the method of electrical energy (fossil fuel vs renewable) generation when conducting a LCA and deciding which technologies to use, since they have a major influence on the aforementioned impacts. The biogas yield of algal and sludge substrates was similar with an average gas production of 241 ml/g volatile solids fed. Biogas from algae fed digesters had a significantly higher methane content (64.73±0.81 %) and lower carbon dioxide content (22.94±0.24 %) when compared to WAS fed digesters (60.08±0.18 % and 27.37±0.43 %) respectively due to it being a less oxidised substrate. Swiss chard plants (Beta vulgaris) fertilised with anaerobically digested (AD) algae or sludge had a significantly higher mean biweekly yield (5.08±0.73 kg/m2) when compared to the inorganic-fertiliser control (3.45±0.89 kg/m2; p<0.0001). No difference was observed in the soil’s physical fertility when algae or sludge were applied to the soil (p>0.05). The HRAP produced more biomass (317.18±27.76 g/m3) than the AS (83.12±64.91 g/m3), which resulted in a significantly greater downstream production of biogas and fertiliser per volume of effluent treated. According to the LCA, this also resulted in the HRAP system having a higher terrestrial ecotoxicity, due to the greater volume of solids and thus heavy metals applied to the soil. This interpretation can be misleading, because the mass of heavy metals released into the environment is the same for both systems, with a greater portion being applied to the land in the HRAP scenario and discharged into fresh water in the case of AS. Future LCA models should clarify if these biomasses are going to be applied to a single piece of land or multiple sites as this will influence the risk of contamination via pollutant build up in the soil. The application of sludge or algae on soil increased the soil’s sodium concentration and sodium absorption ratio from 774.80±13.66 mg/kg to 952.17±34.89 mg/kg and 2.91±0.04 to 3.53±0.13, respectively. Regulations on the application of algae or sludge on agricultural soils should be altered to consider the limit values for sodium and future LCA’s associated with effluent treatment facilities should incorporate the possibility of soil contamination through sodium build-up. This work also conceptualised the importance of reporting water emissions in wastewater treatment LCA in as much detail as possible, because this had a significant influence on the eutrophication impacts on water systems. Reporting water emissions as total nitrogen underestimated downstream eutrophication impacts compared with those using nitrogen-species concentration (ammonia, nitrite, nitrate etc). A marine eutrophication sensitivity co-efficient should be included in future LCA models which accounts for the probability of nitrogen and phosphorus emissions entering the coastal environment as well as the vulnerability of the marine environment to eutrophication. Activated sludge systems are favourable for situations where space is limited, were there are inadequate options for biomass disposal (biomass not be used in agriculture or AD) and were electricity is generated from a renewable source; whereas, HRAP are more suitable under circumstances where electricity production relies on fossil fuel that carries a high environmental impact and where options are available to use the biomass for economic gain such as biogas and fertiliser production. This thesis contributes towards a zero-waste brewery effluent treated process. The HRAP and AS treated effluent for reuse in the brewery or in agricultural irrigation. The solids were anaerobically digested, and the carbon was recovered as a biogas, while the digestate was applied as an agricultural fertiliser. This allowed for the recovery of water, nutrients and carbon.
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Date Issued: 2020

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Synthesis, characterisation and electrocatalytic behaviour of three series of Metal Organic Frameworks

- Murinzi, Tafadzwa Wendy

Authors: Murinzi, Tafadzwa Wendy
Date: 2020
Subjects: Electrochemistry , Metal-organic frameworks , Polyoxometalates , Fourier transform infrared spectroscopy , Electrocatalysis , Cysteine
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167598 , vital:41495
Description: Metal organic frameworks (MOFs) have received a lot of attention over the past few years due to their vast range of interesting properties and applications, such as catalysis, environmental sensing and storage. This wide range of potential applications is afforded by careful selection and manipulation of the components chosen in assembling of MOFs. In this study, three series of MOFs were synthesized from Co(II), Cu(II) and Mo(VI) polyoxometallates with either 1,3,5-benzenetricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid or 2,6- pyridinedicarboxylic acid as the ligands. In series 1, the common 1,3,5- benzenetricarboxylic acid MOF, HKUST-1, and POM modified HKUST-1 compounds involving encapsulation and encorporation of the POM were utilised. In series 2, flexible cobalt(II) benzenepolycarboxylate MOFs which investigated the effect of varying the degree of carboxylate substituent were utilised. In series 3, flexibly reduced heterocyclic polycarboxylate MOFs using 2,6-pyridine dicarboxylate were utilised. Solvothermal and slow evaporation synthesis conditions were employed. Where single crystals of good quality were produced, single crystal X-ray diffraction (SC-XRD) was employed for structural elucidation. In the absence of such crystals, a combination of elemental analysis, inductively coupled plasma optical emission spectrometry (ICP-OES) and powder X-ray diffraction (PXRD) was used. Characterization of the MOFs was done by Fourier transform infrared spectrometry (FTIR) and thermal methods, namely thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The electrocatalytic potential of the compounds in the oxidation of L-cysteine was then investigated using a variety of techniques. Cyclic voltammetry was used for L-cysteine detection whilst chronoamperometry and differential pulse voltammetry were used to determine the nanoprobes’ sensitivity, rate constants and detection limits. Electrochemical impedence spectroscopy was used to investigate the charge transfer resistance (RCT) and electron transfer kinetics. Of the three, series 3 gave the best signals and sensitivities for electrocatalysis of L-cysteine followed by series 2 and lastly series 1. Series 2 showed the highest stability and series 1 required the least overpotential. The results highlight the effects of different metal centres and ligands on electrocatalysis. The application of MOFs in electrochemistry is a relatively new field making the findings of this study a significant addition to the body of knowledge.
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Date Issued: 2020

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Temporal patterns and seasonal variation in microplastic loads in the water column and in the tissues of consumers along the southern and south-eastern coasts of South Africa

- Redelinghuys, Suzanne

Authors: Redelinghuys, Suzanne
Date: 2020
Subjects: Microplastics -- South Africa -- Eastern Cape , Plastic marine debris -- South Africa -- Eastern Cape , Marine pollution -- South Africa -- Eastern Cape , Ocean circulation -- South Africa -- Eastern Cape , Marine invertebrates -- Effect of pollution on -- South Africa -- Eastern Cape , Marine animals -- Effect of pollution on -- South Africa -- Eastern Cape , Mexilhao mussel -- Effect of pollution on -- South Africa -- Eastern Cape , Mytilus galloprovincialis -- Effect of pollution on -- South Africa -- Eastern Cape , Barnacles -- Effect of pollution on -- South Africa -- Eastern Cape , Tetraclita -- Effect of pollution on -- South Africa -- Eastern Cape , Octomeris angulosa -- Effect of pollution on -- South Africa -- Eastern Cape
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/115623 , vital:34201
Description: Plastic pollution in the marine environment has become an environmental concern and a subject of ecological research. The field of microplastic pollution in particular has expanded dramatically in the last few years. Though much data exists on the spatial variability of microplastics in the marine environment globally, little is known about temporal variability, especially on short-term time scales in the southern hemisphere. Similarly, virtually nothing is known about the temporal patterns in microplastic ingestion by marine invertebrates, despite the fact that numerous studies have demonstrated that vertebrates and invertebrates routinely ingest microplastics with varied physiological effects. This study aimed to, 1) provide base-line data for microplastic loads in the nearshore environment along the Eastern Cape Province of South Africa over four short-term time scales: daily, weekly, monthly, and yearly; and, 2) assess whether there are any seasonal patterns in microplastics ingested by selected filter-feeding consumers at two sites along the southern and south-eastern Cape coastlines of South Africa. Results for part one of this study demonstrate no temporal patterns over the different time scales considered (ANOVA, p > 0.05 in all cases). Microplastic counts ranged on average from 55 ± 289 to 930 ± 462 microplastic particles.m-3. With the exception of two instances, microfibres constituted > 50 % (range: 47 to 97 %) of the total microplastic counts. Part two of this study assessed the size range of, and seasonal and spatial patterns in ingested microplastic. No significant differences were found in the number of microplastics ingested within seasons between the mussels Perna perna (Linnaeus, 1758) and Mytilus galloprovincialis (Lamarck, 1819), and the barnacles, Octomeris angulosa (Sowerby, 1825) and Tetraclita serrata (Darwin 1954) (Student’s t-test; d.f = 18; p > 0.05 in all cases), or between the two sites sampled, Kenton-on-Sea, Eastern Cape, and Wilderness, Western Cape (ANOVA; d.f. = 18; p > 0.05 in all cases). The nitric acid digestion technique was used to determine the presence of ingested microplastics. Microplastic loads ranged from 2 ± 1 to 33 ± 19 microplastics.g-1 wwt across all consumers, and the size of ingested microplastics ranged from 1 to 16 μm. Though highly variable, the absence of statistically significant differences in ingestion rates points to a ubiquity in the availability of microplastics within the water column over time and space.
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Date Issued: 2020

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The current role of palm species Hyphaene Coriacea and Phoenix Reclanata in local livelihoods in the Zitundo area, southern Mozambique

- Martins, Angelina R O

Authors: Martins, Angelina R O
Date: 2020
Subjects: Ilala palm -- Economic aspects -- Mozambique , Palms -- Economic aspects -- Mozambique , Non-timber forest products industry -- Mozambique , Sustainable development -- Mozambique , Conservation of natural resources -- Mozambique
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/150613 , vital:38989
Description: The majority of rural households in developing countries are heavily dependent on non-timber forest products (NTFPs) to fulfill much of their basic daily needs. In Mozambique more than 64% of the population lives in rural areas and depends heavily in the extraction of NTFPs to complement agricultural production. One substantial source of NTFPs are palm species. Palms are sources of food, building materials, cloth, ornaments, medicines, and are also used for cultural purposes. In southern Mozambique two important palms species used as NTFPs are Hyphaene coriacea and Phoenix reclinata. These two species provide an array of subsistence and commercial products. The sap, leaves and stems of these two palms are harvested by local people as sources of traditional beverages, weaving, roofing, fencing and furniture material as well as other household utensils. The effects (if any) of harvesting of these palm products on palm distribution, population structure, dynamics and viability have never been examined, and thus the sustainability of the practices and benefits flows to local livelihoods are unknow-n. Any effects harvesting effects may also be exacerbated by predicted climate change for the area. The present study aims to investigate the role of the palm species Hyphaene coriacea and Phoenix reclinata in the livelihoods of households in the Zitundo area, Matutuine district, southern Mozambique and under future climate scenarios. Specifically, this study: i) evaluates the abundance, population structure and harvesting selection of these species; ii) characterizes the ethnobotanical knowledge and use of the two species; iii) examines the local production and trade of palm wine in the area; iv) examines the contribution of palm income to livelihoods and income diversification in area; v) describes the local management practices and perceptions on palm productivity and abundance; and vi) models the current and future distribution of the these palm species in the area. To evaluate the abundance, population structure and stability of these two palm species a population census was carried out, and the size class distribution, Simpson index of dominance, permutation index and the quotient between successive size classes were calculated. I further calculated the preference ratio for specific size classes. Additionally a questionnaire survey was conducted with 179 randomly selected households from the 16 villages in the study area to characterize the ethnobotanical knowledge and use of these two species, as well as to examine the contribution of palm income to livelihoods and diversification. Standard ethnobotanical indices were used as measures of each palm species use and knowledge while principal component analysis and cluster analysis were applied to highlight the livelihood patterns and the role of diversification and of palm income in local livelihoods. Structured interviews with 37 palm tappers were additionally used to examine the local production and trade of palm wine in the area, while both the household survey and palm tappers interviews, were employed to investigate the local management practices and perceptions on palms productivity and abundance. Maxent Software was used to model the current and future under climate change distribution of the two palm species. Hyphaene coriacea was more abundant than Phoenix reclinata. Both species exhibited steep negative slopes in the regression analyses of size class distribution, indicating the presence of more individuals in shorter size classes. Although there was a dominance of shorter over taller size classes, limited recruitment was observed through low stem densities of seedlings and juveniles compared to the 1-50 cm size class The Simpson index of dominance, the permutation index, and the fluctuating quotients between the consecutive size classes showed a level of instability in both populations. Hyphaene coriacea appeared to be more resilient to tapping than Phoenix reclinata as showed by the higher rate of stem survival after tapping. Hyphaene coriacea was favored for tapping compared to Phoenix reclinata. The most preferred size class to tap for both species was between 101cm and 150 cm. Currently the distribution of Hyphaene coriacea and Phoenix reclinata was mostly confined to the eastern side of the study area. Most of the area was predicted as unsuitable for both palm species, with less than six percent predicted to be suitable or higher. The occurrence of both species appeared to be influenced mostly by water related variables, such as precipitation, and distance to rivers and distance to water bodies. The habitat suitability for Hyphaene coriacea was predicted to increase under future climate conditions scenarios, while little variation was predicted for Phoenix reclinata distribution. The knowledge about the uses of these two palm species was widespread in the area, although only 32% of respondents were engaged in palm exploitation. Thirteen palm products were exploited, with palm wine production from the sap of both palms being the dominant activity, followed by broom production from Phoenix reclinata stems and basket production from Hyphaene coriacea leaves. The cultural importance of these species included the production of anklets and skirts used during traditional dances and the use of palm wine in the traditional ritual of libation. Palm tapping was practiced year round in five of the sixteen villages in the area. Palm tapping was an important livelihood activity, contributing over 80% of tappers’ total annual income, and tappers earned up to three times more than the national minimum wage for the agricultural and forestry sector. Palm wine was also a highly commercial commodity in Zitundo area, with an average commercialization index above 60%. The income from palm wine sales showed an important role in mitigating the level of poverty in the area. Palm income accounted for over 60% reduction on poverty incidence among palm tappers. Households in Zitundo further engaged in some level of livelihood diversification. The majority of households adopted a wage-based strategy, although this strategy was among the less remunerative in terms of per capita cash income. A palm-based livelihood strategy, although adopted only by 11% of households, was one of the most remunerative strategies. Palm income played a vital role in enhancing household livelihoods and mitigating poverty in the area as shown by the lower poverty incidences among households engaged in the palm-based livelihood strategy than alternatives strategies. The village of household residency, along with household demographic and socio-economic characteristics appeared to determine the knowledge and exploitation level of palms as well as a households’ choice of livelihood strategy, level of palm wine returns, commercialization index and palm income dependency. The importance of palms in local livelihoods and poverty alleviation needs greater acknowledgement by government and development agencies in the area. Palm wine, broom and basket production have a high potential for income generation, and therefore should be included in future local development policies and poverty reduction strategies. Although palms are an open access resource in Zitundo area, the perception is that they are abundant and that tapping does not have many detrimental effects. However, this study found some negative impacts of tapping on the recruitment of both palms species. The inclusion of palm products in future development programs and poverty reduction strategies will require the design of participatory conservation and management strategies that involve all palm users groups and others stakeholders and include long-term participatory monitoring of the effect of palm use on the populations.
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Date Issued: 2020

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The determination of whether a Unified Communication System can be effective in supporting informal communication and collaboration in virtual teams

- Hill, Kyle

Authors: Hill, Kyle
Date: 2020
Subjects: Telecommuting , Virtual work teams , Telecommunication systems , Computer networks
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/146343 , vital:38517
Description: The overall objective of the research is to determine whether a Unified Communication System intervention can be effective in supporting informal communication and collaboration in virtual teams. In so doing, this research is aimed at developing a current framework of critical success factors for facilitating informal collaboration and communication. As teams have evolved to the point where there is no longer a need for team members to be co-located, with a greater importance now being placed on how they collaborate, this framework will also highlight how it can support virtual teams due to the huge potential advantage they can provide to the organisation. A virtual communication and collaboration system will be selected based on the outputs of the current framework and interactions which occur through the system will be observed to provide quantitative and qualitative results. In conclusion, the research will suggest recommendations for the successful implementation of informal communication and collaboration technologies within the organisation. The research will also indicate to a limited degree, the impact of the implementation of these technologies, and the outcome for the organisation, whether positive or negative. Whilst conducting the research, it became apparent that while the UCS was capable of performing the processes and functions required, the individuals and teams engaging with the technology did not always make use of the full scope of the technology provided. Regardless, a UCS was observed to provide direct benefits to an organisation in increasing communication and collaboration in the organisation. These increases can be observed in both the physical and virtual sense. However, the converse is true for generating social capital which lead to the observation that there are a smaller number of interactions happening in the smaller teams, but these are of higher value when compared to the larger teams of this study. It is also clear that the larger a team becomes, the more the trend is to focus on adopting new technologies to make their roles more efficient. This adoption is not however translated into outputs such as social capital but is translated into stronger networks and the formation of new networks. It is also clear that most negative factors around the UCS are related to the respondent’s hardware rather than the solution itself. Cost reductions because of virtuality will also be observed and using the Developed Framework as a blue print, an organisation should be able to observe direct benefits for an organisation by being able to confirm the thesis of this research in that having a UCS intervention is effective in supporting informal communication and collaboration in virtual teams.
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Date Issued: 2020

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The effects of economic and political instability on decentralised secondary schools in Mashonaland Central Province, Zimbabwe: a case study

- Katsinde, Tapfuiwa James

Authors: Katsinde, Tapfuiwa James
Date: 2020
Subjects: Education, Secondary -- Political aspects -- Zimbabwe , Political violence -- Zimbabwe , Zimbabwe -- Economic conitions -- 1980- , Zimbabwe -- Politics and government -- 1980-
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/165610 , vital:41263
Description: The purpose of the study was to analyse the effects of economic and political instability on decentralised secondary schools in Mashonaland Central Province, Zimbabwe between 2000 and 2017. Previous studies in Zimbabwe and elsewhere have shown that schools were negatively affected by economic and political instability. This study adds to this literature by using habitus as a conceptual framework. This was a qualitative study which made use of a multi-case research design. Data was collected using focus group discussions, interviews and document analysis. Eight research sites in the form of secondary schools in four districts were used. Data analysis was done using theoretical prepositions guided by research objectives and research questions. Data presentations was characterised by quotes of participants. Trustworthiness based on dependability, credibility, transferability and conformability formed the basis of quality assurance measures. The study revealed that economic and political instability had similar negative results in the field of secondary schools in the province. Economic instability negatively affected school activities which included teaching and learning, administration and development work. In addition economic instability affected individual secondary school actors psychologically. Economic instability affected relations among the secondary school actors by aggravating already existing contestations amongst actors. Similarly, political instability affected secondary school activities such as teaching and learning, school administration, development, donations and social benefits. Secondary school actors were individually affected psychologically and through physical abuse and the way they responded to political instability. The study has shown that decentralised secondary schools found it difficult to solve the problems introduced by economic and political instability especially when the instabilities occurred within the difficulties of the broader Zimbabwean context. It is therefore recommended that decentralised secondary schools should be assisted financially and with resources to withstand economic challenges. There is a need to protect secondary schools from political activities and activists as these have devastating effects on education if allowed to have a free reign. Further similar research is recommended for other provinces in the country.
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Date Issued: 2020

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The forensic mental health profile of women offenders in the Eastern Cape, South Africa

- Nagdee, Mohammed

Authors: Nagdee, Mohammed
Date: 2020
Subjects: Female offenders -- Mental health , Female offenders -- South Africa -- Psychology , Female offenders -- South Africa -- Mental health , People with mental disabilities and crime , Women murderers -- South Africa , Forensic psychology -- South Africa , Fort England Psychiatric Hospital
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/167109 , vital:41438
Description: Introduction There is a dearth of research on mental health issues in women offenders in South Africa, especially regarding their socio-demographic backgrounds, offence characteristics, and forensic mental health profiles. Objectives This study examined the psychosocial and forensic mental health profile of women offenders referred by eastern Cape courts for forensic evaluation. A range of socio-demographic, criminological, clinical and forensic mental health variables were systematically explored. Methods A bi-phasic, mixed methods study design was adopted. The clinical and forensic records of all women referred for forensic evaluation to Fort England forensic psychiatric hospital in the Eastern Cape, South Africa were retrospectively reviewed, comprising 173 individual cases in the study period of 1993-2017. Inferential statistical analyses (chi-squared and multivariate logistic regression) were applied to explore relationships between variables and offending outcomes of nterest. Detailed semi-structured interviews were subsequently conducted with a sub-sample of 8 women with mental disorder and violent offending ackgrounds. Interview transcripts thematically analysed. Results Most women came from impoverished and disadvantaged backgrounds. Whilst the majority were first offenders, a high proportion had violent index offences, with murder, attempted murder and assault with intent to do grievous bodily harm accounting for over half of cases. The majority of victims of violence were well known to the perpetrator, especially as biological children, intimate male partners or close family members. Biological children in their first year of life were particularly vulnerable to being victims of homicidal violence. Disproportionately high rates of pre-offence mental illness, alcohol misuse, HIV infection and prior abuse of the offender (especially by intimate male partners) were present. High rates of severe mental disorders (especially psychiatric comorbidity and psychotic-spectrum disorders), and relatively low rates of personality disorders and substance disorders were diagnosed. The majority of women were declared to lack trial competence and criminal capacity, respectively, following forensic evaluation. Women who had backgrounds of prior abuse themselves had over three mes the odds of subsequent violent offending in general, and almost six times the odds of homicidal offending in particular. Homicidal offences were significantly more commonly committed by women with no prior psychiatric history and no psychiatric comorbidity. Women who committed homicide had over eleven times of killing children as opposed to adults. Women over the age of 30 years, and those without psychiatric comorbidity, were significantly less likely to have killed children. Thematic analysis of interviews emphasized the important roles played by gender, self-image, and mental health in violent offending pathways. Conclusions A complex array of socio-demographic, criminological, clinical and forensic variables interact in women offenders of the Eastern Cape referred by courts for forensic evaluation. Exploration of these factors improves understanding of the broader psychosocial context of female offending, and of the personal experiences of the women themselves. This in turn provides an enhanced gender-focus to guide the progressive changes required in policy, legislative, clinical and research endeavours in this field.
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Date Issued: 2020

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The incidence of musculoskeletal disorders and stakeholder perceptions of work challenges in South-Eastern Nigerian quarry mining industry

- Egwuonwu, Victor Afamerfuna

Authors: Egwuonwu, Victor Afamerfuna
Date: 2020
Subjects: Quarries and quarrying -- Health aspects -- Nigeria , Musculoskeletal system -- Diseases -- Nigeria , Miners -- Health and hygiene -- Nigeria
Language: English
Type: text , Thesis , Doctoral , PhD
Identifier: http://hdl.handle.net/10962/141263 , vital:37957
Description: Musculoskeletal disorders (MSDs) are very common among industrial labourers, leading to sick leave absence, disability and low productivity at work. MSDs have multifactorial causes, thereby making it difficult to pinpoint the extent of the contributions of the various risks regarding the mechanism of its pathophysiology. Previously, attempts were made to study regional pain symptoms in varying occupational groups, disregarding the particularities of the different workplace situations. It is important to highlight, that quantifying physical exposure factors that contribute to MSDs occurrence using quantitative approach alone could be inadequate. It is therefore imperative to incorporate qualitative approach to unmask accompanying psychosocial stressors, which are mostly explanatory variables. The study investigated the following: 12-month retrospective prevalence of MSDs, prospective incidence, risk factors and pattern of MSDs in a 6-month follow-up survey of selected quarry mineworkers, who reported MSDs complaints at the mine clinic. The study also determined the level of psychosocial stress associated with working in the mine by understanding stakeholders’ perception of work challenges, and how it influenced recurrence of MSDs. The study utilised a mixed method design with two phases: phase 1 was an initial baseline retrospective prevalence and a prospective cohort-control incidence survey. The Cultural and Psychosocial Influence on Disability (CUPID) questionnaire was translated into an Igbo-language version, cross-culturally adapted and utilized. The instrument was administered via oral interview and sought information on the following: demographic characteristics; pain in different anatomical sites and associated disability for tasks of daily living; as well as information on any change of job and reason during the study period, recent pain in different anatomical sites and associated disability for tasks of daily living; distress from common somatic symptoms; mental health status, sickness absence in the past 5-months for musculoskeletal pain. Phase 2 was a qualitative focus group discussion that engaged mine stakeholders on their perceptions of work challenges. Descriptive statistics of mean and standard deviation was utilised to analyse sociodemographic characteristics of participants. MSD incidence rates were estimated and the patterns of MSD incidence at different anatomical sites were also determined. The Cox proportional regression analyses were utilised to compare hazard ratios of MSD risks between the exposed cohorts and unexposed cohorts in the phase one incidence survey, alpha level was set at 0.05. Transcription, thematic and content analyses with the aid of Nvivo version 11 for windows was used to interpret stakeholders’ perception of work challenges. The incidence of MSD was 6.2 per 1000, with shoulder pain being the most reported complaint (40% prevalence). This was followed by back pain with the distribution of back pain presented as follows: upper back (20.37%), lower back (45.50%) and both (34.13%). All participants reported previous medical history of back, shoulder and neck pain. The relative risk ratio of mineworkers to MSDs was 4.57, which implies that the mineworkers were approximately 5 times more at risk of developing MSDs compared to the recruited unexposed cohorts. Meanwhile, wrist pain (43.58%) was the highest MSD complaints which lead miners to be absent from work, followed by knee and back with 35.42% and 21% respectively. Physical job risks, such as III working underground and squatting or kneeling at work were all significantly associated with MSDs recurrence in all six body parts (HR: 1.12-1.92, 95%CI). Similarly, time pressure to complete task, low decision latitude, poor job satisfaction, somatisation and mental disorder, job insecurity, poor incentive system (HR: 1.01-1.75, 95%CI) were perceived by stakeholders’ and participants alike in the study to be significantly associated with MSDs incidence. Quarrymen are exposed to high MSD risks associated with elevated psychosocial stress from their difficult work situations. The South Eastern Nigerian mine stakeholders believed that the high incidence of MSDs may have a substantial impact on health and productivity in the near future. Necessitating a clear need for the promotion of stakeholder’s engagement concerning safe work policy implementation initiatives in the sector.
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Date Issued: 2020

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