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Item Open Access Rural Small, Medium and Micro Enterprises And Role of Local Economic Development Agencies in the Vhembe District, Limpopo Province(2006-09-16) Matloga, Selokela Reginald; Musyoki, A.Small, Medium and Micro Enterprises (SMME) are vital factors in the economy of less developed countries. It has been a major source of employment, motive force for local economic development and poverty alleviation in developing countries including South Africa. It is agreed world wide that strong SMMEs give a country strong economic growth. In South Africa, SMMEs are not strong especially in rural areas, which comprise mainly of emerging SMMEs owned by Africans. There are hosts of institutions in South Africa which are active in the development of rural SMMEs. Local Economic Development Agencies (LEDAs) in the study areas are engaged in helping rural SMMEs to flourish. However, rural SMMEs are still facing many problems and are unable to flourish. This research is aimed at evaluating Local Economic Development (LED) support on local rural SMMEs in the study area in order to advance feasible strategies for support to enhance rural SMME's growth from the survival stage. Social survey methods involving interview schedules were used, providing descriptive and analytic data. The qualitative and quantitative data was analysed using an SPSS programme. The research findings indicate that LED support in the study area is failing to enhance rural SMME growth. The support does not cover the entire business requirement necessary for rural SMME growth. The study therefore advances strategies for LED support, which would be effective enough to enhance rural SMME growth and sustainability.Item Embargo Analysis of gully erosion as a hydro-geomorphological hazard in Thulamela Municipality, Limpopo Province, South Africa(2025-09-05) Makuya, Asakundwi; Kori. E.; Maponya, M. G.Gully erosion, a severe form of environmental process, poses significant global environmental and socio-economic challenges, worsened by deforestation, overgrazing and climate change. This study examines gully erosion as a hydro-geomorphological hazard in Thulamela Municipality, Limpopo Province, South Africa. The aim of this research was to investigate the occurrence and intensity of gully erosion in Thulamela Municipality. The study's first objective was to map gully distribution in Thulamela Municipality. The second objective was to map the severity of gullying. The third and last objective was to map factors contributing to gully erosion formation. This study investigated the three objectives across four temporal benchmarks (2008, 2013, 2018 and 2023) using GIS and Remote Sensing techniques. Distribution in gully occurrence was tracked through interpolation. Sampled gullies were overlaid to assess their size and shape transformation over time to determine the severity of gully erosion. Land use/cover changes were classified to track how they influenced gully development over the 15-year period. Topography was analysed based on elevation, terrain characteristics, flow accumulation and flow direction to determine areas that are more prone to gully development. Rainfall was assessed based on its intensity and distribution over the period of the study to determine how it contributes to gully erosion. Soil moisture was analysed to determine susceptibility to gully erosion. The results revealed a significant and exponential increase in gully development influenced by all the analysed factors. The findings highlight that Thulamela Municipality contains areas highly susceptible to gully erosion, presenting severe threats to land stability, safe habitation and sustainable development.Item Embargo Spatio-temporal analysis of extreme rainfall events in Limpopo Province(2025-09-05) Muzila, Fulufhelo Marvellous; Kori, E.; Muthige, M. S.This research on the spatiotemporal analysis of extreme rainfall events in Limpopo Province is critical for understanding the changing rainfall patterns, intensity, and frequency, which have significant implications for water resources, agriculture, infrastructure, and disaster management. However, there is a lack of comprehensive and localized spatiotemporal analysis of extreme rainfall occurrences, particularly in Limpopo Province. The main aim of this study was to analyse spatial and temporal patterns of extreme rainfall in Limpopo province by identifying historical trends, frequency, intensity, and spatial distribution using statistical and geospatial techniques. This was undertaken using historical rainfall data obtained from the South African Weather Service (SAWS). The analysis involved using Geographic Information System (GIS) to examine trends in the frequency and intensity of extreme rainfall, analyse their spatial distribution, and analyse trends in extreme rainfall events using the Student's t-test, to determine the significance and Sen’s slope to assess the magnitude of those trends. Extreme precipitation indices developed by the World Meteorological Organization Expert Team on Climate Change Detection and Indices were used. The findings showed that the majority of Limpopo province saw an increase in the intensity of daily rainfall, aligning with global trends overall. A reduction in precipitation during the rainy period was observed in most regions of the east and northeast, while the eastern and southern sections near the slope received seasonal drought. Mara, Oudestad, and Tshivhasie tea Venda showed a strong upward trend in Consecutive Wet Days (CWD), R20mm, and R95p and a decline in Consecutive Dry Days (CDD) from the period of 1993-2023, showing that as the mean rainfall increases, so do extreme rainfall occurrences. In addition, the mean annual rainfall significantly influenced extreme precipitation indices in Limpopo Province. By assessing long-term trends and spatial variations, this study will assist decision-makers who emphasize climate resilience and sustainable development to properly allocate resources and establish areas that need attention in terms of managing impacts associated with droughts and floods, as well as enhancing local interpretation of rainfall and resource allocation to promote sustainability in the province.Item Embargo Effectiveness of Institutional Flood Adaptation Actions and Plans in Vhembe District Municipality, South Africa(2025-09-05) Nwanamidwa, Pfarelo; Nethengwe, N. S.; Mugari, N. E.The increasing frequency of climate-related disasters, including floods, can be attributed to a complex connection of environmental and anthropogenic factors. Proactive adaptation actions and plans are crucial for reducing flood risks and consequences, particularly in vulnerable rural communities. South Africa has made significant progress in flood risk reduction but face challenges in balancing structural measures with local adaptation strategies. Vhembe District Municipality experiences heavy rainfall, leading to floods, particularly in low-lying areas. This study, therefore analysed the perceived effectiveness of existing flood adaptation actions and plans used in response to flood disasters in Vhembe District Municipality and provide recommendations to enhance the effectiveness of the adaptation actions and plans. This study utilised a mixed-method approach, combining questionnaires, key informants interviews, and document reviews to comprehensively assess the effectiveness of flood adaptation actions and plans.The study identified various adaptation actions, measures, legal frameworks and acts used in response to flood disasters; this encompasses a range of measures, including structural, non-structural, and institutional approaches, such as the construction of flood barriers, and levees, early warning systems, and community response teams. The findings show that the nature of flood adaptation planning within Vhembe District Municipality is not inclusive; community members are not involved when planning, designing, and decision-making of the adaptation plans. The findings reveal that the perceived effectiveness of the existing adaptation actions and plans is inadequate and ineffective, which highlights that there is a significant need for improvement in the flood adaptation actions and plans. The findings suggest that Vhembe District Municipality improves its level of community engagement by including traditional leaders, local stakeholders, and residents in decision making. There is a need for improvement, which includes enhancing flood infrastructure, early warning systems, and drainage systems. These measures can strengthen communities' ability to withstand and recover from flood events.Item Embargo Suitability of Thulamela Clays for Use in The Ceramic Industry: A Case Study in Thulamela Municipality, Limpopo Province, South Africa(2025-09-05) Ralushai, Murendeni; Odhiambo, Beneah D.; Kori. EdmoreThis study investigated the suitability of Thulamela Municipality clay samples for ceramic applications by examining their physical, chemical, and mineralogical properties. A comprehensive analysis was conducted using various tests, including particle size analysis, Atterberg limits, X-ray fluorescence (XRF), and X-ray diffraction (XRD). The study evaluated the clays' strength, cracking, water absorption, and linear shrinkage during and after firing at different temperatures (300°C, 700°C, 800°C, 900°C, and 1150°C), aiming to assess their potential for ceramic use. The study analysed the physical and chemical properties of clays from various locations. Sieve analysis revealed well-distributed particle sizes, while hydrometer analysis showed varying clay and sand content. Atterberg limit tests indicated high plasticity, and XRF analysis identified aluminium oxide (Al2O3), silicon dioxide (SiO2), and iron oxide (Fe2O3) as dominant chemical elements. XRD analysis detected quartz, kaolinite, and hematite as primary minerals, with variations between samples. The study identified Ha-Matsika, Lwamondo, Muledane, and Dzingahe clays as having optimal ceramic properties, suitable for high-end applications like refractory ceramics and sanitary ware. These clays exhibited moderate to low water absorption rates and stable linear shrinkage behaviour. In contrast, clays from Ngwenani, Madadani, Tshilungoma, and Tshino are better suited for less demanding ceramic products. The study's findings have significant implications for the ceramic industry, highlighting the potential of local clay resources for producing high-quality ceramics. The study recommends further research to improve the properties of certain clays (Ngwenani, Madadani, Tshilungoma, and Tshino). Utilising local clay resources can enable the ceramic industry to adopt sustainable practices, produce high-quality products, and promote environmentally friendly manufacturing.Item Embargo Synthesis of Ce/Al/Fe Tri-Metal Oxide Modified Diatomaceous Earth /Chitosan Composite Films for Fluoride Removal from Groundwater(2025-09-05) Budeli, Tshilidzi Llyod; Mudzielwana, R.; Gitari, M. W.Sustainable Development Goal 6.1 calls for developing technologies to improve water quality for human consumption to ensure clean drinking water for everyone by 2030. This study aims to contribute to the goal by synthesizing Ce/Al/Fe metal oxides modified diatomaceous earth and the fabrication of Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films for the adsorption of fluoride from drinking water. The results were presented in two chapters i.e. Enhancing the fluoride adsorption efficiency of diatomaceous earth through modification by Ce/Al/Fe metal oxides and Synthesis of Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films for fluoride removal from groundwater. The first chapter of results focused on enhancing the fluoride adsorption efficiency of diatomaceous earth through modification by Ce/Al/Fe metal oxides. Adsorption experiments were performed to determine the efficiency of the Ce/Al/Fe metal oxides modified diatomaceous earth in fluoride removal. About 98% fluoride removal efficiency was obtained from an initial fluoride concentration of 5 mg/L using 0.6 g/100 mL adsorbent dosage at an initial pH range of 7 after 50 mins’ agitation time. The adsorption kinetics models revealed that fluoride adsorption occurred via chemisorption, while the isotherm models confirmed both monolayer and multi-layer adsorption. Thermodynamic studies showed that the adsorption process was spontaneous, endothermic, and random, as denoted by the negative ΔG˚, positive ΔH˚, and positive ΔS˚, respectively. Regeneration studies showed that Ce/Al/Fe metal oxides modified diatomaceous earth can be reused for 8 successive regeneration-reuse cycles. This study revealed that modification of diatomaceous earth with Ce/Al/Fe metal oxides enhances the adsorption of fluoride and the material has the potential for use in defluoridation of groundwater. The synthesized adsorbent in the first chapter had low permeability due to its fine particle size which limits its applicability in a column set-up. Therefore, there was a need to further modify the synthesized adsorbent. The second chapter of results aimed to synthesize the Ce/Al/Fe tri-metal oxide modified diatomaceous earth-chitosan composite films for removal of fluoride from drinking water. The modified DE/chitosan films were developed using the casting method. The functional groups, elemental composition and morphology of the synthesized material were characterized using Fourier Transform Infrared (FTIR) and scanning electron microscopy-energy dispersion X-ray (SEM-EDX), respectively. Batch experiments were conducted to evaluate the effectiveness of the material in fluoride removal. The results showed 7.89 mg/g adsorption capacity towards fluoride from 5 mg/L initial fluoride concentration, when adsorbent dosage of 0.3 g/100 mL was used at initial pH range of 7 after 50 mins agitation time at shaking speed of 200 rpm. The data for adsorption kinetics showed a better fit to pseudo-second order which indicates that the adsorption mechanism was chemisorption. The adsorption isotherm model data best fitted to Langmuir isotherm model which suggests that the adsorption took place on a monolayer surface. The presence of co-existing anions such as Cl-, SO42-, CO32- and NO32- reduces the fluoride removal efficiency of the material. The Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films showed lower adsorption capacity relative to Ce/Al/Fe tri-metal oxide modified DE. Based on the results obtained, the synthesized Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films can be used for Groundwater defluoridation. It is therefore recommended that future studies further modify Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films to enhance their fluoride affinity. Furthermore, future studies should evaluate Ce/Al/Fe tri-metal oxide modified DE/chitosan composite films performance in a column set-up and further evaluate their anti-microbial potency.Item Embargo Development of an acid mine drainage treatment technology and recovery of minerals(2025-09-05) Shumba, Albert; Gitari, W. M.; Mudzielwana, R.; Ayinde, W. B.Acid mine drainage (AMD) is known to have negative environmental impacts due to low pH, high concentrations of toxic metals which can pollute freshwater sources. There is need for development of a technology which treats and recover beneficial minerals from AMD. Samples of AMD, water, sediments from the field and sludge from neutralization batch experiments were characterised for their chemical compositions using advanced research techniques. In designing the treatment method, hydrogeochemistry of decanting AMD from Mpumalanga was studied. Findings from this study revealed that decanting AMD continues to threaten the environment due low pH, high Electrical Conductivity (EC) and precipitation of secondary minerals. Simulated AMD prepared by choosing concentrations of worst-case scenario from Mpumalanga was used in batch experiment comparing flocculation and sonication techniques in treatment of AMD with calcined magnesite. Sonication technique was more effective in treatment of AMD because it raised pH faster and it enhanced precipitation of minerals than flocculation. Due to the superiority of sonication, it was used for recovery of metal oxides from AMD with calcined magnesite through sequential selective precipitation and recycling of metal enriched sludge over several cycles using filtration and pH adjustment. The technology enriched Fe -rich and Al-rich sludge up to cycle 3 while Mn-sludge up to cycle 2. Fe, Al, and Mn in product water were below the guidelines for irrigation water, while Ca, Mg, and SO42- remained at higher levels. The technology may not be used for recovery of Mn due to co-precipitation with Mg. Future studies recommends the treatment of product water to recover portable water and salts and upscaling the technology to pilot for industrial applications. The high purity of recovered metals suggests their potential use for industrial applications such as catalysts, batteries, fertilizer, and pigment manufacturing.Item Embargo Ambient air pollution monitoring, modelling and human health risks in Thulamela Municipality, Vhembe District of Limpopo Province, South Africa(2025-09-05) Enitan, Ibironke Titilayo; Edokpayi, J. N.; Piketh, S. J.Ambient air pollution is a pressing global environmental concern, with pollutants from natural and anthropogenic sources contributing to deteriorating air quality. This research investigates the impact of sulfur dioxide (SO₂), nitrogen oxides (NOₓ), carbon monoxide (CO), and particulate matter (PM2.5 and PM10) on human health and the environment. PM2.5 in particular is a significant public health risk linked to respiratory and cardiovascular diseases. The study focuses on Thulamela Local Municipality (LM) in Limpopo Province, South Africa, a region with diverse semi-urban and rural environments, where air quality data is limited despite ongoing urbanisation and economic growth. Given the lack of comprehensive baseline data, this study aims to quantify, monitor, and model air pollution while assessing its potential health impacts. This research integrates the development of an emission inventory for criteria pollutants (SO₂, NOₓ, CO, PM2.5, and PM₁₀), real-time PM2.5 monitoring using Dylos DC1700 low-cost sensors (LCSs), PM2.5 dispersion modelling with AERMOD, health risk assessment (HHRA), and machine learning-based predictive modelling. By evaluating pollution sources, exposure risks, and predictive trends, the study provides critical insights to inform air quality management strategies in semi-urban settings. This study developed the first-ever 10-year vehicle emission inventory (VEI) for criteria pollutants (SO₂, NOₓ, CO, PM2.5, and PM₁₀) in Thulamela Local Municipality (LM), South Africa. In addition, it produced the first comprehensive bottom-up emission inventory for the year 2021, quantifying total SO₂, NOₓ, CO, PM2.5, and PM₁₀ emissions from two major anthropogenic sources: vehicular emissions and residential wood combustion (RWC). The results indicated annual emissions of 66.3, 1821.7, 21002.6, 2348.7, and 2649.3 tonnes, for SO₂, NOₓ, CO, PM2.5, and PM₁₀, respectively. RWC contributed over 96% of PM2.5 and PM₁₀ emissions, while NOₓ (84%) and SO₂ (60%) originated primarily from vehicular sources. The spatial analysis revealed that emissions were highest in the southwest and northwest, where population density and human activities were most concentrated. A one-year PM2.5 monitoring campaign (March 2021 – February 2022) was conducted at 14 sites, covering urban, suburban, and rural areas. The strong correlation (R² = 0.75) between Dylos and reference monitors (GRIMM EDM180) confirmed the reliability of LCS performance for PM2.5 measurements. The study found that annual PM2.5 concentrations exceeded both WHO guidelines and SA NAAQS, except at one site. Monthly trends showed higher PM2.5 levels from May to September, with diurnal peaks from 6–8 am and 6–8 pm, primarily influenced by traffic emissions and residential wood combustion. The bivariate polar plot (BVP) analysis identified pollution hotspots near traffic intersections, residential areas, and commercial zones. The study identified significant spatial and temporal variations in PM2.5 levels across different monitoring sites, with higher concentrations in suburban areas than rural ones due to vehicular emissions and wood-burning. VTV2 recorded the highest annual concentration (32.3 μg/m³), while RL4 had the lowest (19.1 μg/m³). The average seasonal PM2.5 levels, despite differences, consistently exceeded air quality guidelines, except in summer for specific locations. The results also showed that evening PM2.5 concentrations were generally higher than morning peaks, highlighting significant differences in pollution levels across the area. Using AERMOD, PM2.5 dispersion was modelled to assess spatial patterns and regulatory compliance. Results showed that pollution hotspots exceeded SA NAAQS (40 μg/m³ daily, 20 μg/m³ annually) and WHO standards (15 μg/m³ daily, 5 μg/m³ annually), with the highest daily PM2.5 concentration (49.2 μg/m³) in densely populated areas. Model validation comparing modelled and monitored PM2.5 showed systematic underestimation (R² = 0.176, negative fractional bias), indicating unaccounted sources such as biomass burning, unpaved roads, industrial activities, and agricultural emissions. At Lunungwi village (RL receptor group), the modelled hourly PM2.5 concentration (47.12 μg/m³) exceeded the observed value (32.27 μg/m³, FAC2 = 0.25), indicating localised overestimation. Daily peaks aligned with morning and evening rush hours. At the same time, monthly trends from May to September reflected seasonal variations and increased residential wood combustion, while a notable decline in July 2021 was due to COVID-19 lockdown restrictions, highlighting the impact of reduced human activity on air quality. Although AERMOD has limitations in accounting for some emission sources, it effectively identified pollution hotspots, offering valuable insights for policy interventions and air quality management. The study further assessed long-term exposure and health risks using the HHRA model, focusing on risk characterisation. The USEPA health risk assessment revealed that PM2.5 exposure posed both non-carcinogenic and carcinogenic risks, with infants and toddlers being the most vulnerable. Hazard Quotient (HQ) values exceeded safe limits (1.10 in winter) due to high PM2.5 levels in colder months. Excess Lifetime Cancer Risk (ELCR) values surpassed the acceptable threshold (10⁻⁴) for all age groups, with adults facing the highest long-term cancer risks (2.35 × 10⁻¹). These findings emphasise the urgent need for air pollution control measures, particularly in areas with high residential fuel combustion and vehicular emissions. To enhance PM2.5 predictions, machine learning models were applied using meteorological variables. Random Forest (RF) outperformed Multiple Linear Regression (MLR) and Polynomial Ridge Regression (PRR), with the highest R² (0.80) at VP4 for site-specific predictions and 0.604 for area-wide estimates. Seasonal performance showed better RF accuracy in winter (R² = 0.58, RMSE = 2.10 μg/m³) than in summer (R² = 0.45, RMSE = 4.72 μg/m³), reflecting the impact of seasonal meteorology on PM2.5 dispersion. In conclusion, this research provides a holistic approach to quantifying air pollution sources, exposure risks, and predictive modelling in Thulamela Municipality. The study highlights urgent public health risks and the need for stronger air quality regulations, improved monitoring networks, and targeted mitigation strategies by establishing a clear link between air quality and human health. The findings underscore the need to expand emission inventories, refine meteorological inputs, and integrate multi-pollutant assessments to develop a comprehensive air quality management strategy. To address identified challenges, the study proposes mitigation strategies, including eco-friendly phytoremediation techniques, promotion of cleaner cooking and transport technologies, and urban planning measures to minimise exposure in densely populated areas. By combining scientific research with practical applications, this work aims to support sustainable air quality management, improve public health, and contribute to a healthier environment.Item Embargo Evaluating the biomass of palatable grass species in the communal rangeland using the integration of UAV data with high-resolution satellite data(2025-05-16) Mavhina, Murendeni Sharon; Malahlela, O. E.; Murungweni, F. M.The biomass of palatable grass species plays a crucial role in sustaining livestock within rural and communal rangelands. Accurate biomass mapping techniques are essential in providing insights into the quantification and distribution of palatable grass biomass. Assessing the distribution of biomass and the effectiveness of biomass mapping is one of the important steps for the provision of crucial information on the health of rangelands while facilitating effective land management and sustainable resource utilisation. This study aimed to evaluate the biomass of palatable grass species in communal rangeland by integrating the use of unmanned aerial vehicle (UAV) obtained in December 2022 data with high-resolution PlanetScope(PS) satellite imagery (3 m spatial resolution) obtained in October 2022. The Supervised Maximum Likelihood Classification (MLC) algorithm was employed in mapping land cover classes across the study and achieved overall accuracy of 99.29% and a kappa of 0.98, indicating high reliability in mapping grazing areas. The grazing area size was quantified as 33 695 hectares (ha) from the total 66 982 hectares (ha) of the study area, with grazing areas accounting for 50%, followed by built-up areas (26%) and water bodies (0.21%). The study also evaluated the performance of linear and non-linear regression models for mapping the Palatable grass biomass by comparing the model performance using remotely sensed data derived from the PS imagery. According to the results, non-linear regression models outperformed the linear models, and obtained a root mean squared error (RMSE), mean absolute error (MAE) and coefficient of determination (R2) of 2.15, 1.69 and 0.11, respectively. Additionally, the study tested the performance of linear and non-linear models for mapping palatable grass biomass using the unmanned aerial vehicle (UAV) and PlanetScope data. The comparison between the PlanetScope subset data and the UAV data obtained an RMSE of 2.36 , MAE of 3.22 and R2 of 0.35 for the subset image, and an RMSE, MAE and R2 of 9.83, 6.57 and 0.23, respectively for the UAV data. Both the satellite imagery and the UAV imagery were used to develop and test models for predicting and mapping palatable grass biomass with the use of integration of spectral bands, vegetation indices, and grey level co-occurrence matrix (GLCM) features. These findings demonstrate possibilities offered by remote sensing techniques in improving rangeland management and sustainable resource planning.Item Embargo Mapping roadkill in the Kruger National Park(2025-05-16) Mashao, Talifhani Brilliant; Stam, E. M.; Mokgoebo, M. J.Roads not only create barriers for animals by preventing the free movement of individuals between populations but also cause mortality through collisions with vehicles (i.e. roadkill). In South Africa, most of our understanding of roadkill events stems from research on national and regional roads, but the impacts of roads in protected areas have been understudied. Though there have been ad hoc roadkill reports in protected areas by members of the public on social media, there have been little systematic roadkill surveys undertaken in South African protected areas and, road signage aside, no effective mitigation measures have been applied except traffic officers who are unable to monitor all roads simultaneously. This study formed part of a five-year project to undertake an assessment of roadkill in protected areas and assess mitigation measures to reduce it. This two-year project has recorded temporal and spatial roadkill in one section of the Kruger National Park, on both paved and unpaved roads. During this study a total of 189 roadkill were recorded in a period of 90 days covering 90 kilometres per day, and average roadkill rate was 0.4586 roadkill.km-1day-1. Roadkill incidents were randomly distributed along the roads. Reptiles and birds had most roadkill, and paved roads had a higher number of roadkill than unpaved roads on a per kilometre basis. Most roadkill happened during the hot-wet season. More awareness of roadkill risks is needed to ensure protection of biodiversity in the protected areas.Item Embargo Population Ecology of Rhabdomys dilectus dilectus in the Western Soutpansberg Mountains(2025-05-16) Msimango, Vumboni Harry; Stam, E. M.; Taylor, P. J.; Ganem, G.This thesis explores the population ecology of the four-striped grass mouse (Rhabdomys dilectus dilectus) at the Lajuma Research Centre, within the Luvhondo Nature Reserve in the Western Soutpansberg Mountains, South Africa. Conducted from July 2020 to November 2021, the study examined the species' population dynamics, habitat preferences, and reproductive patterns across three distinct ecological sites: Wetland, Wilderness Camp, and Patches. Specifically, it aimed to assess how environmental variables, such as rainfall and habitat characteristics, influence the distribution, abundance, and reproductive success of R.d. dilectus in these diverse habitats. R.d. dilectus is known to inhabit mesic environments, favoring continuous vegetation cover while avoiding bare soil. However, findings from this study suggest that its habitat range may be slightly broader than previously documented. Extensive bi-monthly trapping sessions using PVC live traps baited with peanut butter, oats, sunflower seeds, and salt were conducted to capture individuals, which were then identified, measured, marked, and released. Habitat characteristics, including vegetation cover and composition, were assessed alongside local weather conditions. Statistical analyses, including non-parametric and parametric tests, Jaccard Similarity Index for vegetation comparison, and rarefaction curves for species diversity, were used to evaluate trapping success, the influence of environmental factors, and the composition of the small mammal community. Results indicate that R.d. dilectus was the most abundant species across all study sites, with the highest population density observed in the Wetland due to its mesic conditions. Rainfall significantly influenced trapping success, with a delayed response linked to increased vegetation growth and resource availability, particularly in the Wetland. The Wilderness Camp exhibited greater species diversity, while the Patches had higher diversity indices despite lower overall species richness. Microhabitat conditions, such as grass cover and predation risk, played a crucial role in shaping the spatial distribution of R.d. dilectus and other small mammal species. Reproductive activity varied across sites, with continuous breeding observed in the Wetland, whereas the Wilderness Camp and Patches exhibited more sporadic reproductive patterns. This research provides valuable insights into the ecological flexibility and habitat preferences of R.d. dilectus, expanding current knowledge of its population dynamics in heterogeneous environments. The findings highlight the role of environmental factors in shaping small mammal communities and offer important implications for the conservation management of rodent populations in fluctuating ecosystems.Item Embargo Impacts of seasonal dynamics on cyanobacterial proliferation and cyanotoxins bioaccumulation in fish species: Comparative study of aquaculture fishponds in Nigeria and South Africa(2025-05-16) Bassey, Odo Jones; Gumbo, Jabulani; Mujuru, M.; Dondofema, F.Aquaculture production plays a pivotal role in advancing Sustainable Development Goals (SDGs), particularly those focused on food security, economic growth, livelihoods, sustainable production, biodiversity conservation, and improved nutrition. Locally produced fish from aquaculture ponds serve as an affordable and accessible protein source in countries like Nigeria and South Africa. However, the rise of cyanobacterial harmful algal blooms (CyanoHABs) poses a serious challenge to the sustainability of fish culture production and human health. In the aquaculture ecosystem, the consequences of these blooms have triggered widespread interest due to cyanotoxin bioaccumulation in cultured fish species. In tropical regions, especially in Africa, there is a paucity of research investigating the temporal drivers of cyanobacterial biomass in aquaculture fishponds. Cyanobacteria are integral to the pond food chain, yet their seasonal dynamics factors and influencing factors remain poorly understood. This knowledge gap is particularly critical as these factors significantly impact aquaculture productivity and the risks associated with cyanobacterial blooms. Therefore, this study investigated the impact of seasonal dynamics on cyanobacterial proliferation and cyanotoxin bioaccumulation in cultured fish. A comparative study design between small-scale commercial fishponds located in Nigeria (NGA) and South Africa was employed in this study. A total of six fishponds located in Calabar Municipality, Cross River State, Nigeria, and Duthuni, Vhembe District, Limpopo Province, South Africa (SA), were selected. Water and Clarias gariepinus (African catfish) samples were collected from each fishpond at seasonal intervals (SA - summer, winter, NGA - dry and wet seasons). Seasonal variations in water quality parameters were observed in NGA and SA fishponds. Cyanotoxins analysis was carried out using the Liquid Chromatography-Mass Spectrometry (LCMS). The results of the study revealed that elevated temperatures (>20°C) were consistent during dry, wet, and summer seasons, with a notable winter decrease (16.5°C) at Duthuni, South Africa. Dissolved oxygen (DO) and electrical conductivity (EC) levels were consistently low across seasons, while total dissolved solids (TDS) peaked during winter in South Africa (125–193.2 mg/L) and were lower in Nigeria (15.9–37.7 mg/L). Nutrients, particularly nitrite and nitrate, peaked in Nigeria during wet (10.42 mg/L) and dry (6.45 mg/L) seasons, while South African fishponds exhibited lower concentrations in both summer and winter. The study revealed that cyanobacterial biomass and cyanotoxins in fishponds were not driven by seasonal factors like warmer temperatures or precipitation. Cyanobacteria biomass was predominantly influenced by management practices, including feeding, fertilization, nutrient levels, water volume, stocking density, water exchange, and retention time. The LCMS analysis revealed that the microcystin variant MC-RR was absent in fish tissue, while MC-YR was detected in the intestines, gills, muscles, and liver. The highest concentration of 20.9 μg/g was found in the liver. Additionally, untargeted LC-MS identified a broader range of cyanotoxins, including aeruginosins, anabaenopeptins, microcystins, and microginins, in the water samples and fish tissue. These findings underscore the critical influence of fishpond management practices on cyanobacterial dynamics and cyanotoxin bioaccumulation. This study highlights the need for targeted interventions to mitigate cyanotoxins risks in aquaculture systems. Understanding and addressing these factors are essential for ensuring the sustainability of aquaculture production and safeguarding public health in tropical regions.Item Embargo Evaluation of public participation process in environmental impact assessments of selected development projects in the Vhembe District of South Africa(2025-05-16) Magosha, Tendani Amos; Nethengwe, N. S.; Mudau, N. V.Ensuring a pragmatic balance between environmental imperatives and community development within Vhembe district in South Africa has been a growing concern since communities’ right to an environment that sustains their wellbeing is being infringed due to ecologically unsustainable development activities carried out in the area. In the wake of this, this research study evaluated the extent to which Environmental Impact Assessments (EIAs) of development projects in Vhembe district complied with public participation as stipulated by EIA policy guidelines and goals provided within EIA legislation in South Africa. The objectives of the study were: to evaluate the level of awareness of guidelines for public participation by the community; to assess the extent to which Environmental Assessment Practitioners (EAPs) have complied with guidelines for public participation in EIA legislations; and to assess public participation practice by EAPs in relation to community expectations in Vhembe district. This study relied mainly on qualitative method of data collection and analysis supplemented by quantitative method. In order to achieve the main aim of this research, a case study was used. Simple random sampling method was done on development projects that required EIA due to their potential to cause irreversible harm to the Earth’s systems thus undermine sustainable development. These development projects were sampled from the four local municipalities within Vhembe district. Systematic sampling was used to identify respondents to whom questionnaires were administered. Interviews were conducted with twelve key informants and also with four EAPs who conducted EIAs for the sampled development projects. The reviewed documents for the development projects included Basic Assessment Reports (BARs); and Scoping and Environmental Impact Report (S&EIR). For data analysis, Statistical Packages for the Social Sciences (SPSS) was used. The results revealed that community members are generally not conversant with EIA guidelines for public participation. Furthermore, it was revealed that EAPs only complied with some of the minimum requirements of EIA procedure. Also notable is that EAPs displayed lack of requisite expertise on how to conduct public participation and as a result infringed on the public’s right to access information by making projects’ information only available in libraries and websites. Key recommendation is that public participation should be made effective and participative by ensuring that community members are capacitated accordingly. As a key contribution to the body of knowledge, this study developed a context-based adaptive strategic framework for ensuring effective and participative public participation practice based on local realities thus to ensure sustainable development.Item Open Access Assessing the potential of biochar to restore degraded lands(2024-09-06) Shirinda, Hazel; Stam, E. M.; Mugwedi, L.Land degradation and climate change are interlinked processes that negatively impact sustainable development. Globally, they pose a risk to human livelihoods, but their effects are even more prominent in developing nations, especially in sub-Saharan Africa. Even with land degradation and climate change currently happening, communities, especially in developing countries, still need to adapt to the changes. This may be due to the high adaptation costs and the need for more knowledge. Biochar is the product of the thermochemical conversion of biomass through pyrolysis. Using biochar as a soil ameliorant has been increasingly advocated because of its effects on soil properties, crop productivity, and carbon sequestration. Biochar has been reported to improve soil quality, crop yield, and soil carbon sequestration potential. Despite this, little is known about the effects of biochar on soil physical properties, making it difficult to recommend biochar to improve soil quality in agriculture. Thus, this study aims to assess the potential of biochar to restore severely degraded land by improving soil properties and crop productivity and mitigating climate change through carbon sequestration at the Lapalala Wilderness Reserve, Waterberg District, Limpopo Province, South Africa. For this purpose, four treatments (biochar, biochar with fertilizer, biochar without fertilizer, and control) were applied to four plots, each replicated five times. A 14-species grass mixture was sown in each of the 20 plots. Soil physical and chemical properties, plant biomass, carbon stock, species richness, and species composition were then measured. None of the four treatments had a significant effect on soil bulk density while only biochar had a significant effect on soil chemical properties of soil Total C, Na and soil pH. No treatment had a significant effect on plant biomass. The analysis of similarity showed no significant difference in species composition for all treatments at month three and month six. The species composition for both treatments and sites for months three and six was mostly similar. The effects of biochar were not significant on soil chemical and physical properties as well as plant growth and biomass. Longer-term studies with higher rates of biochar application are required to confirm the effects of biochar on soil properties, plant growth, and species composition. The biochar feedstock (e.g., agricultural residues, forestry residues, and grassland cutting), biochar properties (such as porosity, bulk density, carbon content) and soil types need to be taken into consideration before application of biochar into the soil to enhance soil properties and plant growth.Item Open Access Synthesis of Acid Leached Diatomaceous Earth/ Amine-Functionalized Activated Carbon Composite and its Potential Application in Oily Wastewater Treatment(2024-09-06) Mabidi, Thinawanga Jennifer; Gitari, W. M.; Mudzielwana, R.; Izevbekhai, O. U.Due to the expanding worldwide oil exploration, a significant amount of oily wastewater is being produced. Oily wastewater lowers the diversity of aquatic life and plants by changing the structure of aquatic communities and food chains, among other ecological disturbances. Therefore, the overall aim of this project is to synthesize acid-leached diatomaceous earth (DE) and amine-functionalized activated carbon composite adsorbent for the treatment of oily wastewater. Acid leached diatomaceous earth was synthesized by leaching the raw diatomaceous step-wisely in a 120 mL volume of 2.2 M Nitric acid (HNO3) for three hours on a hotplate set to 60°C at a speed of 300 rpm. Thereafter, the mixture was filtered and the residue was washed with 1.5 L of deionized water. The residue was oven-dried at 50°C for 12 hours. The acid leached DE was then ground with mortar and pestle and then kept in a zip lock bag for further use in oily wastewater treatment. Activated carbon was synthesized from raw macadamia nutshell using of Orthophosphoric acid (H3PO4). Response surface methodology was used to determine the optimum conditions for synthesizing activated where 3 parameters (activation time, impregnation ratio, and activation temperature) were varied. Furthermore, 13 runs were completed at diverse conditions from the response surface methodology. To modify the synthesized activated carbon, hydroxylamine hydrochloride was used as a chemical agent to enhance the adsorption efficiency on the surface of the activated carbon and the amine-functionalized activated carbon was used in the removal of oil from oily wastewater. Lastly, a composite was prepared using both the synthesized acid leached diatomaceous earth and amine functionalized activated carbon and further evaluate its adsorption capacity and oil removal efficiency. All the synthesized adsorbents were applied in oily wastewater treatment and response surface methodology was used to optimize the variable parameters (adsorbent dosage, initial oil concentration and contact time) and to determine the optimum conditions for the oil removal efficiency. Therefore, this study was divided into 3 sections of results as discussed below. The first section of results is focused on the preparation of acid leached diatomaceous earth and its application in oily wastewater treatment. The results showed that acid treatment does not alter the physical structure of the diatomaceous earth significantly although there was an increase of silica content, its surface area, and pore volume from 78.98 to 91.57%, 15.02 to 22.40 m2/g, and 60.88 to 68.71 Å, respectively. The maximum adsorption capacity of 124.16 mg/g and oil removal efficiency of 78.55% were achieved at initial oil concentration of 3229.69 using 0.05 g adsorbent dosage and 119.20 mins contact time. The adsorption kinetics data fitted better to pseudo-second order model (R2=0.98) of reaction kinetics indicating that adsorption occurred through chemisorption. The adsorption isotherms were descried better by the Freundlich isotherms model (R2=0.87) indicating that adsorption occurred in a heterogeneous and multilayer surface. The second section focused on the synthesis of amine functionalized activated carbon for oily wastewater treatment. Activated carbon was prepared from macadamia nutshells (MNS) using H3PO4 as activating agent and further modified with amine groups using hydroxylamine hydrochloride. Amine-functionalization increases the adsorption capacity and removal efficiency due to expansion of the adsorbent’s particles. The oil removal experiment using amine-functionalized activated carbon showed a maximum percentage removal of 82.93% with adsorption capacity of 167.96 mg/g when initial oil concentration of 10 000 mg/L, adsorbent dosage of 0.1 g adsorbent dosage and contact time of 60 mins were used. The adsorption kinetics data fitted to pseudo-second order model (R2=0.92) of reaction kinetics indicating that adsorption occurred via chemisorption. The adsorption isotherm data fitted Freundlich adsorption isotherms (R2=1) model indicating that adsorption took place on heterogeneous and multilayer surface. The last section of the study focused on the preparation of the acid leached diatomaceous earth/amine-functionalized activated carbon composite adsorbent and its application in treatment oily wastewater. Due to challenges associated with synthesizing an ideal adsorbent for oily wastewater treatment, this composite adsorbent was synthesized to overcome the activated carbon drawbacks which include low thermal conductivity affecting the regeneration efficiency leading to a reduced adsorption capacity after being used for a certain period. Consequently, the advantages of the diatomaceous earth which include excellent heat resistance and its high porosity can improve the physicochemical properties such as surface area and thermal conductivity on the composite adsorbent. The SEM micrographs showed the presence of pores and rough surface with some particles of varying sizes on the surface of the composite material due to the addition of some functional groups which allowed the transfer of the oil molecules into the inner surface of the composite adsorbent. The prepared composite adsorbent showed a maximum oil removal percentage of 90.02% with maximum adsorption capacity of 416.67 mg/g at initial oil concentration of 5250 mg/L, an adsorbent dosage of 0.3 g, and contact time of 60 mins. The adsorption kinetics data showed a better fit to the pseudo-second order model (R2=0.98) showing that adsorption took place via chemisorption. Freundlich adsorption isotherm model descried the adsorption better showing that adsorption occurred on a heterogeneous and multilayer surface. Based on these findings, both materials prepared in this study has potential for use in treatment of oily wastewater. However, the composite displayed higher affinity towards treatment of oily wastewater compared to the acid leached diatomaceous earth and amine-functionalized activated carbon. Based on the conclusions, the main recommendations made from this study were to: 1) test the feasibility of adsorbent in field application and 2) conduct the cost-benefit analysis for this adsorbent.Item Open Access Assessment of pharmaceutical waste management in Vhembe District, Limpopo Province, South Africa(2024-09-06) Malema, Mpho Bridget; Edokpayi, J. N.; Masindi, V.Administering of pharmaceutical products is recognized as a crucial component of healthcare services, since these are used to treat, prevent, and cure diseases, however, rapid population growth has significantly increased the demand for pharmaceutical products, leading to a noticeable surge in their waste generation. This poses serious ecological and health risks if not properly managed, as pharmaceutical waste includes hazardous by-products that can contaminate various environmental spheres. Traces of pharmaceuticals have been detected in wastewater treatment plants, which often lack the necessary infrastructure to remove these compounds effectively. Consequently, the management of pharmaceutical waste is a critical concern for regional, national, and international communities, necessitating a thorough understanding of their management and potential eco-toxicological impacts to devise effective handling and containment strategies. This study was designed to appraise the holistic management of pharmaceutical waste in Vhembe District, Limpopo Province, South Africa. To fulfil this objective, various data collection methods were employed, including questionnaires, on-site observations, and interviews with medical practitioners and waste management personnel. A checklist was used to evaluate compliance with regulatory frameworks, focusing on healthcare facilities and pharmaceutical outlets. Data from observations were analysed descriptively, supported by visual aids like photographs; the interviews were categorized, coded, and abbreviated for easier analysis, while the questionnaire data were processed using SPSS and other statistical tools to generate meaningful outputs. The study's findings reveal significant deficiencies in pharmaceutical waste management within the Vhembe District. Inadequate waste management practices were observed, marked by the absence of source segregation and the use of suboptimal temporary storage containers chosen for convenience rather than efficacy. The infrastructure for waste storage within some of these facilities proved substandard, thereby, failing to meet regulatory requirements. Most facilities rely on municipal waste collection services and the sewer drainage systems, raising environmental and health concerns. The study also identified a significant gap in education and training regarding pharmaceutical waste management with healthcare professionals, who often perceive their responsibility as ending after writing a prescription. This lack of knowledge and preparedness to manage pharmaceutical waste, in line with legal requirements, is a major concern. Additionally, the study revealed participants’ challenges related to understanding waste categories and regulations, hence, emphasizing the need to sensitize healthcare professionals about these regulations. The results showed that 71% of consumers were aware of pharmaceutical waste, but only 20.1% understood its associated environmental and health risks. Alarmingly, 71.8% consumers lacked essential information about the consequences of pharmaceutical waste, and 80% frequently had surplus medications due to practitioners’ over-prescribing or discontinuation of treatment, contributing to waste accumulation. Furthermore, 86% of participants did not segregate pharmaceutical waste from general household waste. A significant 58.3% disposed of pharmaceutical waste in standard trash bins, leading to landfills and potential soil and water contamination through leaching and migration. The study also highlighted the absence of dedicated regulatory measures addressing pharmaceutical waste; they are often categorised under the broader healthcare waste management framework. The existing framework suffers from a disconnect in policy development, implementation and enforcement, with regulations frequently formulated by different stakeholders who do not effectively collaborate. This lack of clarity makes it challenging for stakeholders to understand their separate roles and responsibilities, necessitating improved stakeholder engagement, education, and clear regulatory measures. Future efforts should focus on holistic approaches, proper stakeholder engagement, and stringent regulatory compliance to enhance proper pharmaceutical waste management and conserve the environment for future generations.Item Open Access The Impact of Nandoni Dam construction on selected indigenous plant diversity: A case study in Thulamela Municipality within Vhembe District of Limpopo Province South Africa.(2024-09-06) Thovhogi, Ntevheleni Justice; Odhiambo, B. D. O.; Ligavha-Mbelengwa, H. H.; Mokoebo, M. J.The study assessed the impact of Nandoni Dam construction on selected indigenous plant species (IPS) diversity: A case study in Thulamela Municipality within Vhembe District. The construction of Nandoni Dam started in 1998 and was completed in 2005. The research focused on the following three specific objectives: to examine the selected IPS diversity before dam construction, to determine whether some selected IPS diversity were protected after dam construction, and to assess the community’s perceptions on the need to develop long-term management plans for the conservation of selected IPS diversity. The literature reviewed concentrated on the background of the study, problem statement, justification of the study, Environmental Impact Assessment (EIA), and other studies. Under the methodology of data collection and research design, both qualitative and quantitative methodologies were used. Primary data collection includes field surveys, interviews, and observations. Secondary data were collected from documentary reviews, library books, published articles, theses, etc. Permission was requested and granted by the traditional leaders of Tshiulungoma, Budeli, Dididi, and Mulenzhe villages, which were affected by the construction of Nandoni Dam. For systematic data analysis, the researcher used Statistical Package for the Social Sciences (SPSS) Version 25, narrative, and ethnography. Government officials were visited and communicated face-to-face and telephonically. Ethical consideration was granted by UHDEC. Results: Documentation of selected IPS diversity before 1998; photos of submerged and protected selected IPS diversity after dam construction in 2005. Recommendation: Community environment alliance, public community education on EIA reports, and conservation of selected IPS diversity.Item Open Access Assessing climatic and non-climatic impacts on smallholder maize production in Tshimapha Irrigation Scheme, Limpopo Province.(2024-09-06) Mudzanani, Ntsemeni Rainah; Murungweni, F. M.; Chikoore, H.Globally, climatic extremes and non-climatic factors are a major concern due to their emerging and expected impacts on maize production. Climatic extremes come through drought and floods, whilst non-climatic factors include lack of education, poor management, and lack of support. The study evaluated the impacts of climatic extremes and non-climatic factors on the production of maize yield and further examined measures for sustainable production of maize yield in Tshimapha Irrigation Scheme, Limpopo Province of South Africa. The irrigation scheme was established in the 1960s, and today has 115 smallholder farmers, each having 1.5 hectares. Climate data was obtained from the Agricultural Research Council (ARC), South African Weather Services (SAWS) and from literature. Questionnaires were administered among the 115 smallholder farmers. The key informant interviews were conducted among the farmer’s leaders, community leaders and extension officers. The extension officer and smallholder farmers assisted with generating maize yield data. For the first objective, rainfall data was analysed using Mann- Kendall test analysis in R-Studio. Furthermore, Sen’s slope was also done to determine the magnitude of the trend of the rainfall, monthly, seasonal, and yearly and questionnaires were analysed using Microsoft Excel Version 2310. For the second objective, the Standardized Precipitation Index (SPI) was analysed using rainfall data in Microsoft Excel, and the last objectives were analysed using Statistical Package for the Social Sciences (SPSS) by looking at the percentage distribution. The findings of this study indicated an increase in the intensity and amount of rainfall received during flood years, with floods peaking in January and February. The SPI indicated that the area is not prone to severe drought as it is mountainous. The highest production of maize yield was 3.4 tons, with the least being 1 ton per year (based on the available data). Water and land for farming in the scheme were sufficient before the establishment of the Mutshedzi dam, which restricts access to dam water, and the land taken for some of the farmers during the establishment of the dam. This study is in response to national, regional, and global demand for knowledge on how smallholder farmers can adapt to erratic climates and in support of achieving the Sustainable Development Goal (SDG) Number 2. This study can be useful the in working towards alleviating challenges experienced by smallholder farmers in South Africa to ensure sustainability in smallholder production.Item Open Access Synthesis of Zr4+/Ag+ metal oxides modified zeolite for application in fluoride and pathogens removal from water(2024-09-06) Nemakanga, Selby; Mudzielwana, R.; Ayinde, W. B.People living in developing nations are challenged by acute water scarcity, hence they often rely on groundwater as their primary drinking water sources. Unfortunately, in most cases, groundwater is often contaminated with high levels of fluoride and pathogens, posing a significant health risk. This dissertation aims to synthesize Zr4+/Ag+ metal oxides modified zeolite adsorbent for use in fluoride and pathogens removal from water. The first section of this research aimed at optimizing the synthesis of zeolite from bentonite clay using the response surface methodology (RSM). The process involved alkali dissolution of calcined bentonite clay through ultrasonication, followed by hydrothermal treatment to obtain zeolite. The ultrasonication conditions were optimized by varying NaOH concentration (0.5 to 2.5 M) and aging time (10 to 120 minutes). Temperature (70 °C to 140 °C) and time (1.5 to 6 hours) were evaluated for hydrothermal treatment. The X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDX) and Fourier transform infrared (FTIR) analysis were used to characterize the obtained materials, revealing that crystallinity of the obtained synthesized materials increased at higher hydrothermal temperatures and times. Furthermore, the XRD analysis indicated there was the formation of zeolite NaP phases at lower temperatures and times, while higher temperatures and times led to hydroxy sodalite mineral phases. Preliminary defluoridation experiments were conducted on all hydrothermally treated samples, with the sample prepared at 2 hours sonication, 105°C hydrothermal treatment, and 1 hour 30 minutes exhibiting a capacity for adsorbing fluoride of 0.19 mg/g hence, this zeolite was used subsequent experiments. The second chapter of results presented the evaluated effectiveness of the synthesized zeolite NaP on fluoride and pathogen removal. Batch experiments were conducted to assess zeolite NaP's effectiveness in removing fluoride from water under various operating conditions while the well-assay diffusion method was used to study the antimicrobial potency of the zeolite. The optimum conditions for achieving maximum fluoride adsorption were identified as a contact time of 60 minutes, an initial concentration of 6.2 mg/L using a synthetic fluoride solution, an initial pH of 2, and an adsorbent dosage of 0.5 g/100 mL. Under these conditions, the maximum adsorption capacity reached 0.16 mg/g. Additionally, it was determined that the fluoride adsorption process followed a chemisorption mechanism, as evidenced by the fitting of experimental data to a pseudo-second-order kinetic model. Moreover, the adsorption isotherm data fitted well with the Langmuir model. This indicates that fluoride adsorption occurred on a surface in a single layer, with a limit on the number of active sites at any given time. Antimicrobial assessments revealed that zeolite NaP lacked v potency against gram-negative E. coli and gram-positive S. aureus strains. In conclusion, zeolite NaP demonstrated minimal defluoridation efficiency and no antimicrobial efficacy. The chapter suggests enhancing fluoride adsorption, antimicrobial potency, and material reusability through the introduction of cations into the zeolite frameworks. The third chapter of results focused on the modification of zeolite NaP by incorporating zirconium/silver metal oxides to enhance its efficacy in removing fluoride and pathogens from water. The Zr4+/Ag+ modified zeolite NaP was prepared using 0.5 M and 0.3 M ZrCl4 and AgNO3 respectively. The mixture of 10 g of calcined bentonite, 2 M of NaOH, and Zr and Ag solutions was subjected to ultrasonication for 2 hours followed by hydrothermal treatment at 105 °C for 90 minutes. The obtained material was therefore characterized using XRD, XRF, FTIR, Particle Distribution Analysis, and SEM-EDS. Defluoridation and antimicrobial potency were evaluated through batch adsorption experiments and well-assay diffusion method, respectively. Under optimal conditions, including a pH of 6 ± 0.5, a contact time of 270 minutes, an initial fluoride concentration of 6.2 mg/L, and an adsorbent dosage of 0.5 g/100 mL at an agitation speed of 250 rpm, the modified zeolite demonstrated a peak fluoride removal percentage of approximately 50%. The data fitted better to the pseudo-second-order kinetic model suggesting the dominance of chemisorption as the fluoride removal mechanism while adsorption isotherm data followed the Langmuir isotherm model suggesting that adsorption occurred on a monolayered surface for the Zr4+/Ag+ modified zeolite. Antimicrobial studies revealed a 15 mm and 12 mm zone of inhibition against the gram-negative E. coli and gram-positive S. aureus strains, respectively. In conclusion, the synthesized zeolite functionalized with zirconium and silver metal oxides exhibited improved fluoride removal efficiency and antimicrobial potency. Further research is recommended to improve the properties of synthesized zeolite for better removal of fluoride and pathogens from water.Item Open Access Assessing the effects of sampling time on the accuracy of extracting water quality indicators through geospatial techniques: A case study of Rietvlei Dam(2024-09-06) Rabohale, Mokabolane Innocent; Malahlela, Oupa E.; Mugwedi, LutendoFreshwater is scarce, and the Earth’s ability to supply it is equally limited. Anthropogenic activities, urbanisation, and the effects of climate change degrade freshwater quality at a rapid rate. To design an effective water quality monitoring strategy that can respond to the rapid changes in surface water, regular sampling and analyses are essential. In developing countries, traditional methods of water sampling and laboratory analyses are adopted to generate water quality information. There is, however, a growing global adoption of optical remote satellite sensing for monitoring water quality, in conjunction with field surveys. One of the main challenges of optical remote sensing is sensitivity to cloud cover, which makes it difficult to synchronise with field surveys. This research addressed the question: “What is the effect of sampling time on the accuracy of extracting water quality indicators through remote sensing and geospatial techniques?”, using a case study of Rietvlei Dam, South Africa. The research established the correlation between laboratory-analysed water quality and the Sentinel-2 (S2) data extracted from the months before, during and after the given field sampling date. This covered four sampling periods i.e., mid-winter, late winter, early spring, and mid-spring. Through multiple regression and accuracy analyses, the study determined the efficacy of the S2 remote sensing models for the chlorophyll-a, turbidity, coloured dissolved organic matter (CDOM) and total suspended solids (TSS) water quality indicators from the different field and satellite sampling periods. The S2 remote sensing models predicted the spatial distribution of the water quality indicators and high concentration area coverage of the dam in hectares (ha). S2 models were found to be best for early spring. Chlorophyll-a was extracted five days after field sampling at R2= 0.79; for late winter CDOM was derived 44 days before the field sampling period at R2 = 0.64; for late winter turbidity was optimally extracted 36 days after field sampling season at R2= 0.54; and mid-winter TSS was extracted seven days before field sampling season at R2=0.62. The turbidity and chlorophyll-a S2 models’ spatial prediction of highly concentrated areas covered 36.14 and 28.92ha, respectively. In conclusion, the accuracies of mapping water quality indicators with remote sensing data and field observations differ based on an indicator measured and the time sampling difference between them. In general, the mapping accuracies decrease outside a seven-day sampling difference, whether before or after satellite image acquisition. This study contributes to the scientific understanding of remote sensing applications to the management of water quality in a given area, especially inland water quality.