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Item Embargo Assessing indigenous knowledge systems for management of plant communities and water resources: A case study of Thulamela Local Municipality communities(2026-05-19) Ramasunzi, Ntanganedzeni; Mokgoebo, M. J.; Mudau, N. V.; Netshisaulu, K. N.This study assessed the contribution of Indigenous Knowledge Systems (IKS) to the management of natural vegetation and water resources in Thulamela Local Municipality, South Africa. The research aimed to assess the then-current use of IKS in resource management, identify prevailing indigenous methods, examine challenges to their implementation, and propose integrated management strategies that aligned indigenous and scientific approaches. Using a mixed-methods approach, data were collected from 400 respondents across ten villages through interviews, questionnaires, and field observations. Findings showed that 75% of participants actively used IKS methods such as sacred forest preservation, taboos, rainwater harvesting, storytelling, and community-based conservation. Qualitative insights revealed strong cultural and ecological values attached to these practices, while quantitative data showed clear associations between IKS application and improved perceptions of environmental health. However, generational shifts indicated declining interest among youth, driven by modernization and the lack of IKS inclusion in formal education. Spatial differences also emerged, with traditional villages maintaining stronger IKS practices than more urbanized areas. The study concluded that IKS was vital for local sustainability and climate resilience. Their integration into environmental policy, education, and planning was essential. Recommendations included documentation of IKS, policy recognition, and community-based awareness initiatives to ensure their preservation and application.Item Embargo Environmental Flow Determination in Headwater Catchments of Luvuvhu River in Limpopo Province, South Africa(2026-05-19) Gumbo, Anesu Dion; Nethengwe, N. S.; Kapangaziwiri, E.; Mugari, M. E.South Africa’s national water legislation officially integrates ecological flow allocation within its legal framework, yet implementation in data-scarce, ecologically sensitive headwaters remains uneven and/or underdeveloped. This study addresses the absence of defensible environmental flow requirements (EFRs) in the upper Luvuvhu River Catchment, a biodiversity-rich yet hydrologically compromised system within the Vhembe Biosphere Reserve. Based on a functional flow paradigm, the study aimed to develop and apply a functional flow-based environmental water management framework for headwater catchments in South Africa, to promote sustainable river rehabilitation amid elevated water needs. The research establishes grounded, first derivative, hydrology-based, spatially transferable, and resource-efficient ERF benchmarks using two complementary models: the Revised Desktop Reserve Model (RDRM) and the Global Environmental Flow Calculator (GEFC). The study area encompassed the quaternary sub-catchments A91A to A91D, which are part of the water source area catchment for the upper Luvuvhu River. These sub-catchments are characterised by sharp elevational gradients, seasonal flow discontinuity, and anthropogenic flow alteration. The study applied a multi-layered methodology. Bibliometric and systematic reviews identified knowledge gaps, a site selection protocol combining expert judgment and exploratory factor analysis to isolate representative study zones, spatial characterisation of catchment attributes using GIS and remote sensing, and stakeholder-participatory mapping to co-inform flow target development. Functional flow simulations were run using naturalised flow datasets, with present-day flow datasets used to quantify the impacts of water uses. The RDRM results showed total flow requirements of 46.28 million cubic meters per year (MCM/year) with low-flow thresholds of 19.63 MCM/year for the outlet the Albasini dam (i.e., referred to as point A91AB_Out in the thesis), and 59.42 MCM/year and 25.17 MCM/year respectively, at combined outlet of quaternary A91C and A91D in the Luvuvhu farming region (referred to as A91CD_out in the thesis) under Class D environmental management class (EMC). Monthly distributions and variations of these flow regimes were generated by the RDRM in the SPATSIM framework. The GEFC model results, when applied with global datasets, produced identical e-flow values for both A91AB_Out and A91CD_Out, highlighting its unsuitability for small catchments due to the coarse spatial resolution of input data. In contrast, user-defined datasets provided more realistic differentiation. EMC F, which reflects heavily modified systems, categorised the EFRs and prescribed 21.1% of the naturalised mean annual runoff (MAR) for A91AB_Out and 19.1% for A91CD_Out. A stakeholder-informed framework for determining EFRs emerged from the findings, linking flow targets to default ecological function, hydrological condition, land use stressors, and governance interventions (which would be subject to refinement in further technical stakeholder engagements). The RDRM shows significant applicability within South Africa based on the current resources available (naturalised streamflow datasets). In data-constrained catchments, the GEFC can be used, with caution, as a baseline for EFRs. Recommendations included mainstreaming functional flows into national reserve assessments, expanding climate-informed flow modelling in upland systems, and integrating community-derived ecological knowledge into official flow classification regimes. The study concludes that ecologically meaningful EFR determinations can be achieved in structurally marginalised catchments if methodological flexibility is matched by institutional willingness to accommodate pluralistic, available resource-aware modelling approaches.Item Embargo Impact of Silvicultural Activities on Water Quality in the Thathe Vondo Forest Plantation, Limpopo Province, South Africa(2026-05-19) Ojelade, Babatunde Solomon; Adesoye, Peter Oluremi; Durowoju, Olatunde Samod; Gibb, Stuart W.; Stam, Edward MariaForests are vital ecosystems that control water resources for different life forms, store carbon, and provide goods and services for living organisms. The increasing need for timber and other forest products leads to the advancement of plantation forestry as a crucial technique for managing forest resources sustainably. The plantation, managed intensively for timber production, relies heavily on glyphosate for weed control. Concerns over its persistence, possible runoff, and other contaminants in the soil and water systems have surfaced. This study aimed to evaluate the amounts of glyphosate, aminomethylphosphonic acid (AMPA), heavy metals, microbial contamination, and assess the health risks linked to their concentrations in surface waters and the surrounding soils. It also assessed seasonal and spatial variations and identified the driving factors influencing contaminant levels. Field sampling was carried out during both wet and dry seasons at 16 strategically selected sites within the Thathe Vondo Forest Plantation, located in Limpopo Province, South Africa. Surface water and surrounding soil samples were collected to assess physicochemical parameters, glyphosate and AMPA concentrations, heavy metals, and microbial contaminants. Key water quality indicators—pH, electrical conductivity, turbidity, TDS, temperature, and salinity—were measured in situ using a multiparameter water quality instrument and turbidimeter. In both water and soil samples, glyphosate and AMPA were derivatised and quantified using Gas Chromatography-Mass Spectrometry (GC-MS), while heavy metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Ba) were determined via Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Microbial indicators (total coliforms and E. coli) were enumerated using the membrane filtration technique. The sampling design enabled seasonal comparison of contamination patterns. Data analysis involved statistical methods, including descriptive statistics, Tukey pairwise comparison, principal component analysis (PCA), and Pearson correlation analysis to identify trends, associations, and significant differences across sampling periods and sites. Results showed that glyphosate concentrations in surface waters ranged from 1.55 μg/L (Mufuvhani Stream) to 1.99 μg/L (Tshipfudoni Stream), exceeding WHO's guideline of 0.1 μg/L. Glyphosate concentrations in surrounding soil ranged from 2.22 μg/g (Mukumbani Dam) to 3.94 μg/g (Tshirovha River), far above WHO and SANS thresholds. AMPA was not detected in any samples, suggesting rapid parent compound dominance or limited microbial degradation, possibly suppressed by glyphosate. Glyphosate levels were positively correlated with electrical conductivity and TDS parameters, confirming the influence on ionic balance and salinity. Heavy metals in surface water revealed elevated values in Al (up to 73.52 μg/L), Cr, Mn, Co, and Fe, with wet season samples from the northeastern plantation zones recording the highest levels. These metals likely originated from both herbicide formulations and natural lithological weathering. PCA grouped glyphosate, Fe, Mn, and Cr into a strong component, indicating co-mobilisation through seasonal hydrological processes. Microbial contamination was severe. E. coli levels exceeded 100,000 CFU/100 mL in Tshitareni Stream during the dry season, while even the lowest count (Mapengoni Stream) reached 15,833 CFU/100 mL. Total coliforms peaked at 6.18×10⁴ CFU/100 mL in the Xhaxhani Stream. Contamination persisted across seasons, highlighting inadequate barriers between anthropogenic activity and water sources. Health risk assessments revealed alarming trends, especially glyphosate in children with CDI via water ingestion reached 0.0929 μg/kg/day at Mukumbani Dam (HQ = 0.9287), approaching the risk threshold. Soil-based exposure resulted in HQ > 1.0 across all sites, with a peak of 1.8387 at Tshirovha River. Lower CDI and HQ values were recorded for adults, yet some exceeded safety margins. HQ and HI for metals such as Cr, Fe, and Mn surpassed 1.0 in wet and dry seasons in Gwadza and Lwathuwa Streams, posing a chronic risk. QMRA infection probabilities for E. coli exposure reached 1.00 annually for all sites, with no substantial seasonal improvement. These findings confirm the environmental burden introduced by glyphosate-based forestry. The absence of AMPA suggests poor microbial resilience or inhibition of degradation pathways. An increase in the levels of heavy metals, alongside an increase in the microbial population, exacerbates the risks associated with ecosystems as well as the health of the public. Spatial patterns highlight the importance of hydrological movement, timing of herbicide application, slope of the land, and livestock proximity as dominant ranching influences. The study recommends urgent environmental precautions, including the establishment of vegetative buffer zones to trap runoff, restriction of herbicide application to dry intervals, fencing off water sources from livestock, and seasonal water quality monitoring for glyphosate, metals, and pathogens. Educating local communities that rely on untreated water is also critical. Consequently, this research utilises empirical evidence to inform forest management policies and develop integrated, ecologically sensitive weed control strategies that protect human health and ecosystem function.Item Embargo Geographic analysis of waste management practices in rural and urban schools: A case study of Maruleng Municipality, Limpopo Province, South Africa.(2026-05-19) Maponya, Makhei Jonas; Mudau, N. V.; Netshisaulu, K. H.This study examined the geographical factors influencing waste management practices across eleven primary schools in the Maruleng Local Municipality, comprising two urban and nine rural schools. Data was collected through focus group interviews with teachers and support staff, supplemented by a quantitative analysis using Chi-square tests to explore associations between school type and waste management challenges. The findings reveal clear disparities between urban and rural schools, with rural schools remaining significantly disadvantaged due to inadequate infrastructure, limited municipal waste collection, and entrenched informal disposal methods such as burning and burying waste. These practices reflect a reactive and unsustainable approach to waste management. Nonetheless, initiatives such as composting, recycling clubs, and environmental awareness programmes illustrate potential pathways for fostering environmental stewardship within school communities. The results further show that effective and sustainable waste management cannot rely solely on infrastructure; it depends on the interaction between cultural practices, learner behavior, institutional support, and municipal service provision. The success of composting initiatives at Seagotle, Makgwahleng, and Lepono demonstrates that integrating waste management activities into the school curriculum can position schools as catalysts for environmental change. In contrast, urban schools displayed more structured systems supported by partnerships and formal disposal mechanisms. Grounded in the Theory of Planned Behaviour, the study concludes that improving school-based waste management requires strengthening positive environmental attitudes, promoting supportive social norms, and enhancing perceived behavioural control through the provision of adequate resources, training, and municipal collaboration.Item Embargo Synthesis of carbon nanotubes from tyre rubber waste for application in the removal of pharmaceutical contaminants in aquatic ecosystems(2026-05-19) Tshotheli, Happiness; Mudzielwana, R.; Pindihama, G. K.The presence of pharmaceutical contaminants in aquatic ecosystems is a growing environmental concern due to their significant impacts. This study was designed to assess the occurrence of amoxicillin, aspirin, efavirenz, and levonorgestrel in effluent of selected wastewater treatment plants (WWTPs) in Vhembe and Mopani Districts, as well as in their respective receiving streams. The study further evaluated the feasibility of synthesising carbon nanotubes (CNTs) from tyre rubber waste for the adsorption of prevalent pharmaceutical contaminants. The first chapter of results focused on assessing the presence of amoxicillin, aspirin, efavirenz, and levonorgestrel in wastewater effluent and the respective streams of the Vhembe and Mopane districts. A total of 42 samples collected in duplicate over a three-month period (July, August, and September) were subjected to solid-phase extraction (SPE), followed by analysis with a High-Performance Liquid Chromatograph (HPLC) coupled with a photodiode array (PDA) detector. The observed concentration range of the analysed compounds were 1.70×10-3 to 4.16×10-2 mg/L (effluent) and 4.0×10-4 to 1.68×10-2 mg/L (surface water) for efavirenz, 3.19×10-3 to 5.34×10-2 mg/L (effluent) and 1.0×10-3 to 2.44×10-2 mg/L (surface water) for levonorgestrel, 0.14 to 4.07 mg/L (effluent) and 0.52 to 4.13 mg/L (surface water) for amoxicillin, 0.46 to 4.75 mg/L (effluent) and 4.70×10-2 5 to 1.19 mg/L (surface water) for aspirin. Based on the results, amoxicillin was prevalent, with the highest concentrations in both the effluent and receiving streams. Owing to the dominance of amoxicillin in all treatment plants, the second chapter focused on the synthesis of CNTs from tyre rubber waste for the adsorption of amoxicillin from water. The CNTs were produced by pyrolysis of carbonised tyres, with ferrocene as a catalyst. For the characterisation of the CNTs, Fourier Transform Infrared Spectroscopy (FTIR) revealed functional groups typical of carbon nanotubes, including C=O, C–H, and C=C bonds. Additionally, Brunauer–Emmett–Teller (BET) analysis indicated a surface area of 90.16 m²/g. Scanning Electron Microscopy (SEM) identified fibrous features, while Transmission Electron Microscopy (TEM) revealed nearly spherical amorphous structures, which were concluded to be SWCNTs. Lastly, the particle size analyser recorded a particle size of 25.53 μm. Batch experiments were conducted to evaluate the removal efficiencies of amoxicillin by CNTs from water under various conditions. The maximum removal efficiency of 96.91% was achieved under the following conditions: a contact time of 90 min, a pH of 8, and an adsorbent dose of 60 mg at 35 °C. Furthermore, the adsorption process better fits the Freundlich isotherm model, indicating a heterogeneous surface influences multilayer adsorption. The adsorption capacity of amoxicillin was determined to be 25.46 mg/g for the synthesised CNTs. Additionally, the kinetics were better described by a pseudo-second order model, suggesting the dominance of a chemisorption mechanism. Adsorption isotherm studies revealed that amoxicillin adsorption on CNTs was endothermic and non-spontaneous. Furthermore, the material remained stable throughout 9 regeneration cycles, with efficiency decreasing to below 80% in the 8th cycle. The maximum amoxicillin removal efficiency from real water samples was 69.99%. From the observed results, the synthesised material has potential for application in the removal of amoxicillin from water In conclusion, amoxicillin, aspirin, efavirenz, and levonorgestrel were present in both wastewater effluent and receiving streams. Amoxicillin was detected at higher concentrations in the samples, prompting an investigation into its removal using in-house-synthesised CNTs derived from tyre rubber waste. This revealed significant potential to source adsorbents from environmental waste. This study further recommends (i) The inclusion of pharmaceutical contaminants in the routine monitoring of contaminants in essential water streams by relevant authorities, (ii) Further studies focusing on tertiary treatment methods targeting pharmaceutical compounds.Item Embargo Evaluating CMIP6 Models in Simulating Southwest Indian Ocean Tropical Cyclone Activity (1979–2014): Comparison with ERA-5 Reanalysis(2026-05-19) Nembilwi, Wamashudu Joel; Chikoore, H.; Engelbrecht, F.; Hodges, K.; Nethengwe, N. S.Tropical cyclones are environmentally and socio-economically destructive phenomena in sub-Saharan. Yet there is still a lack of early warning signs and minimal studies on the simulation of tropical cyclones which attribute more venerability to the societies in the sub-continent. This study investigates the performance of ten global climate models in simulating the characteristics of Southwest Indian Ocean (SWIO) tropical cyclone activities. The model’s simulation was performed for 35 years (1979-2014) and validated against the ERA-5 reanalysis data. The study also considers the influence of large-scale environmental conditions through a calculation of the genesis potential index (GPI). The strength of global climate models was tested through the simulation of the inter-annual variability of tropical cyclones in the SWIO. The results show each CMIP6 model displaying a different signature on simulations. The ten analysed CMIP6 models are capable of reproducing the observed annual mean of genesis potential index (GPI) and its associated terms (environmental conditions) in a given region, but most CMIP6 have a lower genesis potential index (GPI) (including terms) than the reanalysis. The selected CMIP6 analysis indicates that all models produce realistic representations of tropical cyclones over the SWIO, while some underestimate and overestimate tropical cyclone activities such as lifetime maximum intensity (LMI), mean intensity, and genesis. However, models that struggled to resemble ERA-5 reanalysis on tropical cyclone activities were able to simulate the inter-annual variability well relative to the reanalysis. The present study illustrates how different models of horizontal resolution simulate tropical cyclone activities and offers insights on how to improve future projections of tropical cyclone activity over the SWIO region.Item Embargo Characterizing the Land Use and Land Cover Change Within and Around Historically Disadvantaged Institutions of Higher Learning in Limpopo Province, South Africa(2026-05-19) Ramatlou, Moloko Shantel; Malahlela, O. E.; Maponya, M. G.The historically disadvantaged institutions (HDIs) of higher learning in South Africa play a pivotal role in advancing education, socio-economic equity, and development. Over time, these institutions have expanded their infrastructure to support their growing academic and socio-economic mandates. However, this development contributed to significant changes in land use and land cover (LULC) within and around their campuses over the years. These changes resulted in land degradation, water resource depletion, biodiversity loss, and climate change caused by carbon emissions and reduced carbon sequestration and storage. This makes it crucial to understand the effects of LULC changes in and around HDIs in South Africa. The geographical information systems (GIS) and remote sensing applications often aid in detecting changes in LULC. However, techniques used to detect these changes also present challenges. Such challenges include differences in spatio-temporal resolutions, inappropriate classification methods, and a lack of sufficient accuracy or robustness for complex classification tasks. Therefore, the study aimed to characterize the LULC change within and around HDIs of higher learning in Limpopo Province, South Africa. The study was conducted within a 10 km radius buffer area (100 km²) around both the Universities of Venda (UNIVEN) and Limpopo (UL), which are the HDIs. The study had two objectives, namely, to: (i) compare classification techniques for mapping LULC change, (ii) build and test hybrid models for mapping LULC change, and (iii) quantify the extent and rate of LULC change from 2010 to 2023. The Landsat 5 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI) images were downloaded freely from the United States Geological Survey (USGS) website. The downloaded images were pre-processed and used as input for classification. To achieve objective 1, several classification techniques, including Random Forest (RF), Support Vector Machines (SVM), Maximum Likelihood (ML), and K-Nearest Neighbour (KNN), were used to classify LULC. Based on the performance of the individual classifiers, hybrid models were developed using the weighting method that assigned higher weights to the best-performing algorithms to enhance the performance. At the University of Venda, RF and SVM outperformed ML and KNN. The SVM achieved 88.3% overall accuracy with a kappa coefficient (κ) of 0.85, and RF achieved 83.0% with a kappa coefficient of 0.79. The KNN achieved 81.0% (κ = 0.76), and the MLC achieved 73.7% (κ = 0.67). Similarly, SVM and RF at the University of Limpopo performed better than KNN and MLC. The SVM achieved 89.0% (κ = 0.86), RF achieved 82% (κ = 0.78), followed by KNN, which achieved 76.0% (κ = 0.70), and MLC, which achieved 72.0% (κ = 0.65). No significant difference was found between SVM and RF at UNIVEN (p = 0.86) and UL (p = 0.89). No significant difference was detected between KNN and MLC at UNIVEN (p = 0.88) and UL (p = 0.84). There was no significant difference between SVM and MLC at UNIVEN (p = 0.92) and UL (p = 0.93). To achieve objective 2, the best classifiers (SVM and RF) were utilised to construct and evaluate a hybrid model. They were assigned weights of 0.6 and 0.4, respectively, based on their overall accuracy to create a hybrid model (SVMRF) that was compared with the individual classifiers. The SVMRF demonstrated an improvement in classification capability, resulting in enhanced classification results. significantly outperforming individual algorithms. The overall results show a significant difference compared to individual algorithms. The p-value for all comparisons is p < 0.05. To achieve objective 3, the hybrid model (SVMRF) was used to classify and to quantify the extent and the rate of LULC change. The results showed a significant change in LULC between 2010, 2015, and 2023. The result showed notable declines in woodland, bare land, water, and forest in and around the University of Venda. In return, a significant increase was detected in agriculture, tea plantations, and built-up areas. Similarly, in and around the University of Limpopo, areas of bare land, woodland, water, and shrubland have declined, while built-up areas and agricultural land have increased. Across the buffer zones (1 km, 2 km, 5 km, and 10 km radii), the results showed that LULC changes around the University of Venda and University of Limpopo appeared to be driven by rapid settlement expansion fuelled by growing student populations and infrastructure demands. The infrastructure development was spreading into surrounding villages, while agricultural land declined sharply, especially in outer zones (5km and 10 km radii). Woodlands and forests suffered consistent losses, with some forest patches near UNIVEN disappearing entirely, and bare land also shrank slightly. Water bodies initially covered a large area, possibly due to high rainfall, but later declined as a result of land encroachment by infrastructure development, raising concerns in Limpopo’s semi-arid climate. Around the UL, similar trends emerged, with robust growth in built-up areas, slight gains in agriculture followed by losses, and steady declines in woodlands, shrublands, and water areas. These changes pose a threat to biodiversity, ecosystem services, and food security. The results from the statistical analysis showed no significant difference in all the LULC, achieving a p >0,05. The study concludes that hybrid models are more effective for mapping LULC change than individual classifiers. Thus, recommends the use of hybrid modelling for mapping LULC change. Also, the study recommends that future research should use higher-resolution satellite imagery and extend the study period to 30 years to better detect significant LULC change within and around these HDIs.Item Open Access Sedimentological and mineralogical characteristics of Limpopo River Sand at Beit Bridge Border between South Africa and Zimbabwe(2025-09-05) Ramavhunga, Mukondeleli; Odhiambo, Beneath; Kori, EdmoreThe research aimed to investigate the sedimentological and mineralogical characteristics of Limpopo River sand upstream of Beit Bridge, situated on the South Africa/Zimbabwe border. Due to limited information available about the minerals and sediments associated with Beit Bridge, this study was conducted to fill this knowledge gap and enhance knowledge of the river’s history and environmental changes. Samples of sediment representing the river were collected from upstream of Beit Bridge along the Limpopo River. The sieve analysis technique was used to classify the particle size of the samples. The X-ray Diffractometer (XRD) analysis identified mineral composition, detecting quartz, feldspar, and other minerals. The petrographic analysis offered detailed mineral component observations, confirming XRD findings. Subsequently the X-ray fluorescence (XRF) analysis traced sediment provenance by identifying specific elements and compounds, illuminating geological history. The results showed that sand was the most dominant component across all stations, with varying proportions of fine silt and gravel. XRD and microscopic analysis revealed minerals such as quartz, plagioclase, microcline, muscovite, and actinolite to be dominant. The prevalence of quartz suggests a quartz-rich source, while plagioclase indicates a predominance of igneous and metamorphic rocks in the local geological formations. The geochemical analysis indicated intense weathering, as evidenced by the high concentration of SiO2 in the sediments. The SiO2/Al2O3 ratio suggests significant leaching processes. Enrichment of Large Ion Lithophile Elements (LILE) in the sediments indicates a provenance from the subduction zone's geochemical region. The Al2O3/TiO2 ratio reflects diverse sources, including basic and ultrabasic plutonic protoliths. These geochemical insights contribute to understanding the area's geological history and mineral resource potential, guiding future exploration and exploitation efforts. The research successfully determined the sedimentological and mineralogical characteristics of the Limpopo River sand upstream of Beit Bridge. The combination of sieve analysis, XRD analysis, petrographic analysis, and XRF analysis yielded valuable insights into the historical transformations in the river's surroundings and the geological mechanisms that influenced the terrain in the examined area.Item Embargo The Use of Veld Restoration Techniques for Rehabilitating Degraded Waterberg Mountain Bushveld in Lapalala Wilderness Reserve, Limpopo Province(2025-09-05) Munarini, Gumani Colbert; Steyn, J. N.; Dannhauser, C. S.The natural rangelands of southern Africa have undergone significant degradation due to human and climatic activities. Fortunately, rehabilitation measures have been extensively researched and are available to address this issue. A variety of techniques exist to remedy the damage done to our rangeland ecosystems. However, the correct and timely application of these strategies remains a challenge. Further research is needed to provide farmers and landowners with clear and detailed guidelines for successful implementation. This research project aimed to investigate the effectiveness of a combination of rangeland rehabilitation strategies to provide guidelines for the successful restoration of degraded rangelands where a bare and compacted surface has developed as a result prior treatment. Field experiments were conducted to assess the use of brush-packing and other techniques for rehabilitating degraded land. The study took place in trial plots at Lapalala Private Game Reserve in Limpopo Province. Eight treatments were applied, including soil ripping, sowing grass seed mixtures, and covering treated areas with single and double layers of thorn branches known as brush-packing. These treatments were duplicated at two sites within the game reserve, one of which was located inside the enclosure of the Lapalala Wilderness School. Treatments without protection from brush-packing failed to produce sustainable grass growth, as emerging plants were constantly grazed off by herbivores. However, where soil ripping, seed sowing, seedbed compaction, and brush-packing were applied, significantly more biomass was produced, resulting in sustainable growth of grass plants. The research outcomes highlight several key principles for the use of rangeland rehabilitation strategies in areas with bare soil and compacted topsoil crust. Firstly, where soil is exposed with a compacted topsoil crust or hard pan, rainwater penetration and infiltration must be improved. This can be achieved by breaking the compacted hard pan through soil ripping along the contour, allowing surface water to flow into furrows and penetrate the ground. Secondly, while the natural seedbank may provide seeds for pioneer plants to establish in a favourable environment with increased moisture and loose soil, the natural succession process is slow. To accelerate rehabilitation, grass seeds can be sown into furrows. Thirdly, newly emerging seedlings must be protected from grazing animals. The practice of brush-packing has proven effective for this purpose. Double layers of brush-packing create a favourable environment for seedling establishment and growth, offering longer protection than single layers. This protection is crucial for safeguarding grass stems, preventing grazing herbivores from damaging flowers and seeds essential for reproduction and ecosystem restoration. While grazing animals can be managed away from areas undergoing rehabilitation in commercial farming situations with domestic farm animals, this is more challenging in game reserves and parks, making brush-packing a valuable tool in these contexts.Item Embargo Three Quaternary Catchments in Vhembe District Municipality: A GIS Approach(2025-09-05) Musumuvhi, Ndamulelo; Momba, M. N. B.; Dondofema, F.; Nethengwe, N. S.This study investigates microbiological water safety risks in three quaternary catchments within the Vhembe District Municipality (VDM) using Geographic Information Systems (GIS). The aim is to assess the abundance and distribution of faecal indicator bacteria (FIB) in surface and groundwater sources across wet and dry seasons and to examine the impact of land use on FIB levels. Using GIS, we analyzed FIB concentrations in rivers and boreholes. The study found higher FIB levels during the wet season due to increased runoff. Significant contamination was observed in the Mutshindudi and Luvuvhu rivers, and in groundwater sources, notably in A91E, A91F, and A91G boreholes. Land use significantly influenced groundwater contamination, with bare soils, cultivated lands, and vegetation showing higher FIB levels. Furthermore, there were no significant differences (P = 0.05) in FIB levels between water treatment plants and households (e.g., faecal coliforms: Z = -1.342, p = 0.180; E. coli: Z = -0.535, p = 0.593). One-Way ANOVA indicated significant differences in FIB levels across land use categories during the wet season (e.g., A91E E. coli: F (3,15) = 16.601, p < 0.001).In conclusion, GIS proves to be a vital tool in assessing and managing microbial water safety risks, offering essential insights for sustainable water management in rural areas.Item Embargo The effect of product formulation on the uptake efficacy of micronutrient elements applied as foliar sprays and how micronutrients affected fruit set and yield of Macadamia trees(2025-09-05) Mushezha, Rolivhuwa; Steyn, Jacobus; Joubert, ElsjeFoliar fertilization has lately been advocated by some advisors as being a more efficient method of fertilization than soil applications and has been promoted as a viable economic way to supplement the plants’ nutrients (Girma et al., 2007). Through foliar fertilizations, nutrients can be delivered directly to the target organs during critical periods of rapid uptake creating little opportunity for its runoff and waste. The factors affecting the uptake and translocation of foliar applied nutrients by mist blower applicators which produce atmospheric aerosols are however, poorly understood. Many trace elements are also notorious for poor uptake and translocation in plants and many gaps in knowledge in this regard, exist (Niu et al., 2021; Hu et al., 2023). An experiment was conducted to investigate the impact of different formulations of zinc (zinc oxide, zinc nitrate, and zinc chelate) and iron (iron sulphate and iron chelate) on the uptake efficiency of these micronutrient elements when applied as foliar sprays to macadamia trees. Additionally, the study aimed to assess how these micronutrients, along with various other elements (including magnesium, manganese, boron, copper, calcium), as well as two products containing multiple nutrient elements (namely Kelpak (cold pressed seaweed), and Budding Mix (a blend of essential trace elements for budding and fruit set in trees), influenced fruit set? fruit drop? and final yield in macadamia trees. Field trials were conducted in macadamia orchards where trial plots contained 200 macadamia trees each. The trees were of the same cultivar i.e. Beaumont (or ‘695’) and age of 23 years old. A total number of 9 treatments were applied where each trial plot was sprayed three times over a 3-month period to coincide with 3 important phenological stages of the macadamia trees i.e., flowering, fruit set and fruit drop. Each treatment contained a trace element or combinations of trace elements and other nutrients and these were applied as foliar sprays on the leaves of the trees. A control plot received no treatment. Nutrient uptake of the different zinc and iron formulations in the macadamia leaves were analysed and compared and fruit set, fruit drop and final yield were measured for all treatments and compared. Results showed that zinc nitrate was not significantly better taken up by the macadamia leaves compared to the zinc oxide and zinc chelate formulations but showed significantly higher zinc contents than the control. The other two formulations did not show results that significantly differed from the control. Concerning the iron formulations, iron sulphate was not taken up significantly higher than the Fe chelate formulation, but the leaves contained significantly more iron than the control although the Fe chelate formulation did not significantly differ from the control. The second phase of the study produced mixed outcomes. Among all the foliar element spray treatments, Zn nitrate demonstrated the best performance in terms of fruit set, albeit with the highest incidence of fruit drop. Conversely, Zn oxide applications led to the highest yield among all treatments in the final yield results. The evaluation of final yield was particularly crucial, representing the most significant aspect of the study from a commercial agricultural standpoint. While final yields did not show significant differences in many cases among treatments, a gross income analysis revealed slight increases in yield (nuts harvested per hectare), resulting in substantial income boosts. Some treatments resulted in more than R30 000 income per hectare than the control. This finding is noteworthy as South African macadamia nuts are exported, generating foreign currency, and positioning them as a high-value crop. Although the results from this study did not reveal significant and clear outcomes in terms of foliar applications of microelements for the commercial macadamia farming industry, it made two important contributions; firstly, that foliar applications of microelements are indeed a viable way of supplementing micro element deficiencies and secondly, this study demonstrated some knowledge gaps which have also been also been cited by other researches like Hu et al., (2023) and the need for more research in the field of applying micronutrients with the aid of foliar applications for plant nutrition.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.