21623 research outputs found
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Leveraging remotely sensed data and machine learning for quantifying soil organic carbon stocks in woody-encroached areas of Bisley Nature Reserve.
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.Woody encroachment has emerged as a significant driver of land cover change in grasslands, with profound effects on Soil Organic Carbon (SOC). SOC is an important indicator of soil fertility, and thus crucial for grassland productivity. Previously, woody encroachment has been reported as a primary source of SOC alteration in grasslands. However, there are still debates and uncertainties on whether this phenomenon amplifies or reduces SOC sequestration. Therefore, it is necessary to further evaluate SOC accumulation in grasslands affected by proliferation of woody plants. Remote sensing offers freely available and cost-effective data with improved spatial and spectral resolution to quantify SOC. In this regard, the current study aimed to evaluate the role of remote sensing in quantifying the spatial variability of SOC across a woody encroached Bisley Nature Reserve. The first objective focused on quantifying the spatial variability of SOC stocks in both pristine and woody-encroached grasslands using PlanetScope spectral bands and vegetation indices. At a depth of 0-30 cm, the study found that landscapes dominated by woody encroachment exhibited higher SOC values compared to pristine grasslands. Using Deep Neural Networks, a combination of PlanetScope spectral bands and vegetation indices model achieved acceptable accuracy (R² = 0.64) for quantifying SOC stocks at this depth. Interestingly, NDVI was the most important variable for estimating SOC within woody encroached grassland. However, to fully understand the dynamics of SOC accumulation and its vertical distribution across different soil depths, it was necessary to expand the analysis. Hence the second objective extended the investigation by utilizing a Random Forest algorithm and integrating additional remotely sensed data to model SOC stocks at multiple soil depths (0-30 cm, 30-60 cm, and 60-100 cm). This approach provided a more comprehensive view of SOC variability, revealing a higher concentration of SOC in the top 30 cm compared to deeper layers. By incorporating topographic variables, Synthetic Aperture Radar (SAR), Sentinel-2, and PlanetScope data, the model produced higher accuracy for deeper soil layers, with R² values of 0.76 at 60 cm and 0.79 at 100 cm. SAR data enhanced the model by offering insights into subsurface conditions. These findings underscore the necessity of investigating SOC at different depths to fully capture its spatial distribution and highlight the potential of remote sensing and machine learning to improve SOC mapping accuracy across woody-encroached grasslands
Effect of genetically modified sugarcane in combination with sterile insect releases to control Eldana saccharina: a shade house trial.
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.Abstract available in PD
Ujamaa theology and human sexuality in Tanzania: a socio-historical and hermeneutical analysis of Ujamaa literature in the context of same-sex sexuality.
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.This thesis explores Ujamaa theology in the context of human sexuality, focusing on a sociohistorical and hermeneutical analysis of Ujamaa literature to uncover theological and biblical conceptual resources that could be employed in engagement with contemporary contestation over issues of same-sex sexuality in Tanzania. For a broader understanding of Ujamaa and its socio-historical setting, this study interrogates the pre-colonial history of the land that became Tanzania, spanning back several millennia, which is vital for a better understanding of Tanzanian peoples and their intimate ways of life, colonization and Christianization, the spirit of the Ujamaa movement and the need for liberation from colonization and its aftermath.
The study examines same-sex sexuality and explores how eroticism and sexual relationships have been experienced and practiced in Tanzania across time and space. It aims to shed light on aspects of life that were suppressed and silenced by colonial influences and have been neglected by mainstream biblical and theological studies in Tanzania. This study draws from historical texts as well as works by anthropologists, sociologists, medical scientists, and human rights advocates. On one level, it addresses the terminology, concepts, existence, prevalence, socio-cultural attitudes, and representations of same-sex-oriented individuals. On another, it investigates the politics and policies related to same-sex practices, along with religious and cultural discourses surrounding same-sex sexuality in Tanzania
There has been a deliberate crackdown on LGBTIQ persons, and countless people with perceived or assumed same-sex sexuality, LGBTIQ activists and allies whose names and stories are unknown, have suffered brutal physical, verbal and spiritual violence in the hands of some religious leaders, families, politicians and the public in Tanzania. The growing intolerance and violence against same-sex sexuality is foreign to the Tanzanian society of Ujamaa. Equally, denouncement of same-sex sexuality, or even the silence of theologians, is a matter of theological concern that requires interrogation.
Hence, this thesis aims, first, to investigate the concept of Ujamaa and analyze its biblicaltheological elements that could inform contemporary discourse on same-sex sexuality. Second, to examine an Ujamaa interpretive approach to scripture and consider its application in the current Tanzanian context regarding same-sex sexuality. Third, to address issues related to same-sex sexuality, especially violence against LGBTIQ individuals, by utilizing theological insights from Ujamaa theology; and fourth, bring Ujamaa liberation theology into dialogue with present-day concerns surrounding same-sex sexuality, contributing academically to the theologically underresearched field of human sexuality in Tanzania.
Lastly, the study proposes Contextual Bible Study (CBS) on Genesis 18-19 and Galatians 3:26-28 respectively, as theological praxis for an inclusive Ujamaa theology that integrates issues of samesex sexuality through the CBS process, fostering a transformative and prophetic public theology that practically engages with the lived realities of LGBTIQ individuals in Tanzania
Aspects of the urban and rural ecology of Nile monitors (Varanus niloticus) in KwaZulu-Natal, South Africa.
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.Changing land use, which is taking place globally at an unprecedented rate, generally has a negative impact on biodiversity. However, some species persist in or even exploit these anthropogenically modified environments. Little is known about how reptiles are affected by urbanisation, especially in the global South. Nile monitors (Varanus niloticus) are Africa’s largest lizard and are amongst the most exploited tetrapods on the continent, yet they can be found in highly urbanised and densely populated areas of KwaZulu-Natal, South Africa. They remain greatly understudied, with many gaps in even basic aspects of their ecology. They are projected to become threatened in parts of their range without successful management. This thesis focuses on two broad aspects of the ecology of Nile monitors in KwaZulu-Natal Province, South Africa. Namely, a) their distribution and persistence in a mosaic of land-use type and human population density in two focal areas and b) their population size and morphometrics in rural and urban areas.
The aim was to fill important knowledge gaps in the ecology of this highly exploited, charismatic, and yet understudied species to make management recommendations and promote sustainable coexistence of people with Nile monitors in KwaZulu-Natal, South Africa. The first aim was to determine if Nile monitors occur in urban environments in KwaZulu- Natal and what land use types they are associated with. Using 419 Nile monitor sightings, two hotspots were found in the region, one dominated by protected land and the other dominated by mosaics of anthropogenic land use. They were found throughout regardless of human density. However, their use of residential areas was greater in the region with less available natural land.
Increasing human density was positively associated with the use of more wooded habitats, except for planted forests, which were avoided systematically. Their association with water was confirmed; however, increased human density also increased their mean distance to rivers, likely reflecting their use of swimming pools, storm drains and other anthropogenic water features. Both managed and unmanaged green spaces (e.g., gardens, parks, golf courses) in urban mosaic landscapes are important features for the persistence of Nile monitors. The second aim was to estimate the Nile monitor population size using a mark-resight method with baited camera traps on a gradient of land use in three different specific sites and also compare urban and rural morphometrics throughout KwaZulu-Natal. Nile monitor limbs, body width, tail base, heads, and body mass were larger in rural areas but only marginally. Furthermore, we found greater population size estimates with increased habitat modifications (golf course > farmland > nature reserve), but the average estimated snout-vent length decreased. Reduced size may result from intraspecific or interspecific competition and different predation dynamics in urban and rural ecosystems. More independent trigger events of potentially competing diurnal mesocarnivores were recorded in the nature reserve and farmland than on the golf course. Despite the larger population size estimate of monitors, there was evidence of poaching at the golf course. One individual was stolen from a trap, and four instances of deployed snare traps were recorded.
The inclusion of dead individuals for morphometrics has shed light on the added threats caused by domestic dogs (Canis lupus familiaris), people and vehicles for urban monitor populations. It is concluded that Nile monitors are successfully persisting in the mosaic urban landscapes of KwaZulu-Natal but are not as successful as some other urban varanids. The use of anthropogenic land-use, and thus conflict with people, will likely increase with continued land-use change. Future research should investigate Nile monitor interactions with people and pets as well as conflict mitigation strategies and both their urban and rural spatial ecology
Advancing sustainable gravel road construction through innovative nano-emulsion treatment of a micaceous gravel.
No full textDoctoral Degree. University of KwaZulu-Natal, Durban.Materials used for road construction play a critical role in the performance of the pavement structure. Winning and haulage of virgin materials have been highlighted as factors that contribute significantly to the increased construction cost and environmental degradation. In the quest to achieve sustainability, it has been recognised that functionalising locally available materials is one of the ways of tackling the challenge highlighted above. Such materials are enhanced through stabilisation traditionally using products such as cement and lime. However, these (cement and lime) have limitations and various products have been developed and marketed as viable alternatives for material enhancement.
This study evaluated the efficacy of Nano-Modified Emulsion (NME), a relatively new product, for stabilisation of gravel materials, particularly for use as a gravel roadwearing course. NME comprises of Conventional Bitumen Emulsion (CBE) modified with an organofunctional nanosilane. Therefore, the product (NME) draws on the properties of nanotechnology to functionalise and improve properties of materials traditionally considered of marginal quality. Previous studies show that this product has great potential in this regard. However, it is recognised that current knowledge of the product is limited and further research is required on the fundamental properties and behavioural traits of NME stabilised materials (NMESMs) to streamline concepts, understanding, leading to the development of design guidelines of the materials. A marginal quality micaceous gravel material was chosen as a suitable candidate to demonstrate the efficacy of the NME. The material, stabilised with varying NME applications from 0.7% to 1.5%, was evaluated for various engineering properties, including mechanical strength, stiffness and deformation characteristics. Results of tests for mechanical strengths conducted through California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS), Indirect Tensile Strength (ITS) and Static Triaxial Tests (STT) showed improved material properties by more than 70%. It was observed that minimal applications of NME are required to achieve specified strengths and that increasing the application dosage does not significantly improve material strength. The NME is also shown to impart hydrophobic properties on the gravel material such that increased applications of NME increase the gravel’s resistance to moisture damage as determined by the Moisture-Induced Damage Ratio (MDR). The STT results demonstrate that the NME improves the shear strength of materials by increasing the cohesion parameter by up to 54% while the angle of friction remains virtually unchanged. The resilient modulus of NMESMs exhibits a combination of stress-dependent and -independent behaviour and it was determined that the parabolic model suitably represents this behaviour. Results of plastic strain tests also show that NMESMs provide better performance with regard to resisting deformation. Modelling and pavement structure analysis was implemented using a Finite Element (FE) based software, ANSYS 2022 R2. This was done to simulate the performance of the material in an actual pavement structure. It was determined that incorporating a NMESM layer as a wearing course on a gravel road pavement structure improves pavement responses to loading i.e. strain and deflection by up to 14% and 28%, respectively. The use of NMESM also reduces the thickness of the layer, resulting in a saving on materials. Additional studies are recommended for Life-Cycle Cost Analysis (LCCA) to help in quantifying cost-benefit ratios of implementing NMEs in industry
Recruitment and presence of native migratory fish species in the uThukela River estuary and lower uMngeni River catchment, KwaZulu-Natal, South Africa
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.African rivers provide significant sources of freshwater and are ecologically and economically important to human livelihoods, especially regarding income and food sources. In Africa, ~200 million people consume freshwater fish daily, and ~10 million people are gaining an income associated with freshwater fisheries. Unfortunately, African rivers are some of the most unpredictable rivers as they fall victim to extreme variability in precipitation. These rivers and streams are under threat to anthropogenic activities, such as the building of dams, weirs and locks, water extraction, modified river embankments, water quality issues, flow modifications from hydropower dams, and climate issues, that are significant threats to all fish species. Estuaries are unique and highly productive systems that are rich in biodiversity, as they are tidal-driven. An intricate flow dynamic connecting freshwater systems, estuaries, and the sea needs to be maintained for optimum ecosystem functioning. Thus, rivers are fundamental to the connectivity they provide. Physical barriers decrease the ecological connectivity of river systems. This has a major impact on various fish species, especially migratory fish. Migratory fish are major ecological drivers that can shape the structure and function of ecosystems. They are fundamental in maintaining food webs as predators or prey. Many flagship migratory species (i.e. yellowfish (Labeobarbus spp.) and eels (Anguilla spp.) in South Africa are prevented from reaching their breeding grounds. Four of the globally nine recognised species of anguillid eels are located and documented along the East flowing African Rivers, including those in South Africa. A few studies have been conducted on the recruitment of glass eels into the rivers and estuaries in the Western Indian Ocean. There are limited studies on the location of spawning areas of African freshwater eels. Relatively little is known about the migratory requirements of African fish species; only a few quantitative studies have been conducted to support the understanding of the migratory habits of these fish species and their dependency on free-flowing and connected rivers. This study investigated the recruitment of African freshwater glass eels into the uThuleka River. Environmental data were collected. Glass eel species were identified by their tail and caudal fin pigmentation together with DNA barcoding. The findings included seasonal variation in recruitment, but the majority of glass eels were caught in the wet season, in warmer temperatures, during high spring tides and at night. These findings should encourage more frequent sampling in estuaries across all seasons along the Western Indian Ocean coast, as the timing of glass eel recruitment can be used to locate where the African Freshwater glass eels’ breeding area is. Additionally, this study aimed to characterise the risk of multiple stressors, including instream anthropogenic barriers, on the ecology of fish communities and their environmental drivers in the lower part of the uMngeni River catchment. Various fish sampling methods were used to capture fish and investigate their species diversity and evenness. Statistical analyses were used to evaluate the relationship between fish communities and environmental variables, including barriers. The findings showed distinct fish community structures found across all sites in the catchment, which were susceptible to multiple stressors impacting migratory fish, especially velocity and mean depth. These stressors result in impaired river connectivity, which reduces a fish’s ability to recolonise a river's range sufficiently. Restoring and considering river connectivity in the lower uMngeni catchment can potentially improve fish communities
Population ecology of Woolly-necked Storks (Ciconia microscelis) in a South African mosaic landscape.
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.As large, aquatic birds, storks (family Ciconiidae) and their population dynamics can provide useful information about how wildlife respond to changing land use. There are 20 extant stork species with varying conservation statuses, yet few species have received much research and conservation attention. Although storks can act as indicators for their usual wetland habitats, there is increasing evidence that some species are ecologically flexible and can persist in human-altered landscapes. This study aimed to use the African Woolly-necked Stork (Ciconia microscelis;
hereafter, ‘woollyneck’) in South Africa as a case study of urban wildlife colonisation and behavioural plasticity. Previously a rare and secretive species in South Africa, the woollyneck has expanded its range southward in KwaZulu-Natal over the past few decades, especially colonising urban and mixed use landscapes. We investigated how two important components of population dynamics–reproduction and nata dispersal–could have facilitated rapid population expansion in KwaZulu-Natal, and how spatially resident woollynecks use the urban environment. Firstly, we studied the urban breeding ecology of woollynecks by monitoring 112 nesting attempts during two nesting seasons in KwaZulu-Natal. We described previously unknown aspects of the natural history of woollynecks, including clutch size, breeding phenology, breeding metrics, and nest site fidelity. Fecundity in the two study seasons was very different (1.4 nd 0.7 fledglings per pair), suggesting that in some years, woollynecks produce a high number of chicks that may compensate for years of poorer reproductive output. The probability of fledging at least one nestling was significantly related to rainfall and egg-laying date, with higher success probability earlier in a breeding season and when rainfall was higher. Secondly, we investigated the dispersal of immature woollynecks using high-resolution telemetry and low-resolution colour-ring mark-resight. Immature woollynecks had large areas of spatial use, and these areas mostly decreased as they got older. From telemetry, we found the farthest distance moved from a natal nest site was 220 km. Colour-ringed woollynecks were resighted an average of 26.5 km from their natal site, with some as far as 98 km. Finally, we used telemetry to understand how resident adult woollynecks moved in an urban landscape. Adults had very small home ranges (x̄ = 4.37 km2) and travelled very short
distances on average (0.82 km) from the nest while breeding. Apparently, the abundance of nesting trees and food in the form of amphibians in residential gardens and supplemental anthropogenic food has allowed adult woollynecks to become highly sedentary following the colonisation of urban mosaic landscapes in KwaZulu-Natal. The results of this study provide novel insight into (1) how KwaZulu-Natal’s woollyneck population could have expanded so rapidly (i.e., high breeding success and natal dispersal), and (2) how the established urban population of woollynecks move in an urban mosaic landscape. Given the abundance of resources for woollynecks in such landscapes, it is possible the recruitment of a high number of young storks into the population and their far dispersal movements will facilitate the continued expansion of the population southward into Eastern Cape Province and inland in KwaZulu-Natal. In contrast to their historical description as shy and secretive, woollynecks in KwaZulu-Natal have demonstrated unexpected behavioural plasticity in their adjustment to an urban mosaic environment, which suggests other species may have similar capacity that has yet to be observed
Exploring the characterization of Esther and Mordecai in the book of Esther (Masoretic Text MT): a social Identity and biblical narrative criticism theory perspective and its implications for contemporary interpretation.
No full textMasters Degree. University of KwaZulu-Natal, Pietermaritzburg.In an age where identity is multifaceted and often disputed, my dissertation explores the intricacies of social identity in ancient and modern contexts by delving into the narrative of Esther and Mordecai from the Book of Esther Masoretic Text (MT). This study employs Biblical narrative criticism and Social identity theory to reveal how these historical figures navigated their complex identities, mirroring contemporary struggles faced by many, including myself as a mixed-race South African. Drawing from my journey of identity negotiation in post-apartheid South Africa, I find resonances with Esther’s concealment and eventual revelation of her Jewish identity and Mordecai’s steadfastness amidst systemic discrimination. These Biblical characters' experiences of duality and resilience offer valuable perspectives on the ongoing challenges of maintaining cultural heritage while assimilating into new social environments. For example, Esther's hidden identity in the Persian court parallels the modern immigrant experience, where individuals often balance dual cultural expectations. My research questions focus on character analysis through Biblical narrative criticism and (SIT) lenses and aim to understand how Esther and Mordecai's identities were shaped and expressed within their narrative. By examining their portrayal in the Masoretic Text (MT), I seek to uncover broader themes of power dynamics, assimilation, and resistance that are equally relevant today. This intersection of ancient text and modern identity issues enriches Biblical studies and provides a nuanced framework for interpreting contemporary social identities. The study aims to contribute to Biblical studies by integrating social scientific methods, offering a multidimensional approach that bridges historical and literary contexts with modern identity exploration, encouraging a more comprehensive engagement with the complexities of self in a
multicultural world
The evolution of flower colour variation in the endangered grassland daisy Gerbera aurantiaca (Asteraceae)
No full textDoctoral Degree. University of KwaZulu-Natal, Pietermaritzburg.Flower colour variation is widespread within and between populations and has long been a focus for research into natural selection. I investigated the potential factors influencing the capitulum colour variation exhibited by Gerbera aurantiaca (Asteraceae), an endangered grassland daisy endemic to the sub escarpment mistbelt grasslands of eastern South African. Widely scattered and fragmented flower colour polymorphic and monomorphic populations comprise long-lived clones with inflorescences ranging from yellow through orange to deep red. An earlier study investigated some aspects of pollination biology and population structure in the southern monomorphic, red-flowered G. aurantiaca populations, but little was previously known about the yellow and flower colour polymorphic communities in the central and northern parts of the distribution. Geographical variation in flower colour of a plant species may reflect the outcome of selection by pollinators or may reflect abiotic factors such as soil chemistry or neutral processes such as genetic drift. I found no strong associations between morph colour and abiotic factors, including soil chemistry, and plants in a common garden retained the capitulum colour of the source population, even when grown from seed, suggesting that flower colour variation is not a result of phenotypic plasticity. Distribution of the various colour morphs in a flower colour polymorphic population further supported this lack of association. Hopliine beetles were the most abundant flower visitors in all populations and in a colour polymorphic population, all colour forms were equally attractive to these beetles and did not differ significantly in terms of fruit set. Native honeybees visited only yellow capitula in a monomorphic population. I found that G. aurantiaca is largely self-incompatible, completely dependent on pollinators for pollen transfer, and pollen quantity limited in some of the red coloured populations. This species is therefore highly susceptible to pollinator colour sensitivities for visits and fruit set. Hopliine beetle abundance appeared to be the most important factor in fecundity in all populations, but visited all colour forms equally, suggesting that it is maintaining the current colour pattern rather than driving change. The absence of this pollinator in two red-flowered populations has resulted in critically low fecundity. Pre-dispersal tephritid fly seed predators damaged similar numbers of capitula in all study populations making it unlikely that these biotic agents are driving colour variation. Since community flower has been shown to influence the suite of pollinators and subsequently predominant flower colour, I compared the petal reflectance spectra of all coflowering species across five representative G. aurantiaca populations but found no differences. Insect vision models showed that the yellow morphs were visible to honeybees, but the red forms were not different to the background, while all colour forms, in particular red, were conspicuous to the beetles. These results confirmed field pollinator observations. Pigment distribution and petal structure may be important in pollinator attraction. In G. aurantiaca pigments are concentrated in the upper epidermal cells of the ray florets which have an epidermal cuticular surface micro structuring suggesting that pollinator attraction is important in this species. Flower colour inheritance may play a vital role in self-incompatible species in flower colour polymorphic populations. Here I crossed true breeding red and yellow colour forms from different populations which produced primarily yellow and orange F1 offspring, suggesting a polygenic inheritance of anthocyanins in G. aurantiaca. The results presented here show that capitulum colour in G. aurantiaca is geographically structured, but the ultimate evolutionary basis of this colour variation remains elusive, and further research using genetic techniques should be pursued to answer this question. Some recommendations for the long-term conservation of this flagship endangered species are detailed
Fashioning identities: an autoethnographic study of being-becoming a fashion design lecturer at a University of Technology.
No full textDoctoral Degree. University of KwaZulu-Natal, Durban.This visual autoethnography explores my process of being-becoming a fashion design lecturer within a University of Technology, highlighting the fluid and entangled nature of identity formation in academic contexts. Through a feminist new materialist stance, it considers how identities are performed, negotiated, and shaped through intra-actions with the human and non-human. Drawing on theories of performativity, materiality, and intra-action, I move beyond fixed notions of emerging academic identities. From this open, naked space, I embrace the opportunity to engage in multiple relationalities—remaining open to change, fluidity, and the non-rational. The ‘auto’ component of autoethnography positions me as both subject and object of inquiry, entangling my be(com)ing within broader sociocultural and historical contexts. The ‘ethno’ component critiques enduring institutional norms and culture that shape my experiences as a fashion design practitioner. The ‘graphy’ element connects my visual and narrative data to critically examine my be(com)ing as a fashion design lecturer. This analysis highlights the complexities of identity formation in navigating the interplay between academic and professional contexts. Embracing the ‘visual,’ I employ arts-based methods—like comic doodles, metaphor drawings, and concept mapping—to deeply engage with my lived experiences. These visual texts function as data, capturing embodied aspects of becoming a lecturer, and as analytic tools, surfacing cultural narratives and professional tensions that shape my identities as both practitioner and academic. This research demonstrates how arts-based research and visual methods in autoethnography can offer nuanced insights into identity and professional development, challenging traditional methodologies by foregrounding often-unspoken, affective dimensions of scholarly inquiry. This combination of methods, creative practice, and theoretical analysis works together to enrich the understanding of complex, lived experiences within higher education. The findings reveal that visual methods effectively illustrate the intricate processes of uncovering the self, making visible often-overlooked stories of experiences, emotions, and the entangled materiality of cultural norms. Through vulnerability, reflexivity, and creativity, this study challenges conventional writerly academic expectations, moving towards inclusive and dynamic approaches to knowledge production. This visual autoethnography shows practitioner-academics how they might integrate artful inquiry, artistic practice, and scholarly knowledge to enrich the understanding of identity within professional contexts