Natural and Mathematical Sciences Departments

Permanent URI for this community

https://univendspace.univen.ac.za/handle/11602/1914

Browse

Now showing 1 - 20 of 550

Open Access
3D Cranial Morphometry, Sensory Ecology and Climate Change in African Rodents
(2019-05-15) Nengovhela, Aluwani; Taylor,, Peter; Braga, Jose
The order Rodentia is the most speciose group of mammals with muroids being the most diverse superfamily. Since they are represented in arboreal, semiaquatic, subterranean and terrestrial niches, rodents may exhibit morphological traits reflecting their adaptations to such diverse environments. This thesis focuses on the morphology of the endocranium, auditory bulla and cochlea in three tribes (Otomyini, Taterillini and Gerbillini) representing 10 species of African rodents, concentrating on their variability, function and adaptability, using micro-CT imaging and 3D shape comparative methods. Additionally, variations in cranial size were also studied in respective of global warming and climatic variables. Morphological changes/variations are a result of environmental change, therefore each chapter in this study details the effect of environmental change (in space and time) on different morphological traits i.e. general cranial size (chapter 2), cochlea and auditory bulla (chapter 3) and endocranial size and shape (chapter 4). With chapter 2 dealing specifically with climate change in its strict sense and the remaining two chapters looking at different environmental gradients. Chapter 2 tests the applicability of the “third universal response to warming” (i.e. declining body size) and the Resource Rule in two murid subfamilies, Murinae and Gerbillinae. The study shows that the third response is not as universal as only one species conformed to this response. Further, food availability (Resource Rule) was shown to be the more important factor correlated with body size variations in rodent species than Bergmann’s Rule. Chapter 3 looks at the auditory bulla and cochlea, the morphological traits that play a role in hearing capabilities of rodents. I found, with some exceptions, that bulla and cochlea modifications between species could be explained by environment, phylogeny and/or allometry. In addition, I concluded that true desert adapted laminate-toothed rats and gerbils use both bulla and associated cochlea hypertrophy. Chapter 4 shows larger brain size in Taterillini and two species of Otomyini, with life histories and environment being the most probably factors responsible for xiv this. Using a novel method of diffeomorphism (deformation models), there was more variation in endocranial morphology between the gerbils and laminate-toothed rats than within them with olfactory bulb, paraflocculi, and posterior ventral cortex showing the most variability. Overall, this thesis shows that variations in the morphological traits studied are strongly influenced by the environment and function.
Open Access
A metagenomic snapshot of selected wastewater treatment plants in Vhembe Region, Limpopo, South Africa: Investigating the resistome
(2024-09-06) Jacobs, Damien; Potgieter, N.; Traore, A. N.
Background: Water is crucial for human life. Rural communities often rely on natural water sources which may become polluted by wastewater due to various activities such as domestic use and agriculture. Antibiotic resistance genes (ARGs) may be transferred from wastewater to the environment and pose a global challenge they affect both human and animal-related sectors. Studying antibiotic resistance in wastewater treatment plants within Vhembe offers a representation of antibiotic resistance genes from entire communities. Knowledge of antibiotic resistance circulating in Vhembe has been sparsely studied. Metagenomics approaches allow for a broad overview of the resistome and the bacterial communities within environmental samples. Aim: To perform wastewater surveillance of antibiotic resistance genes and associated bacteria within Vhembe, Limpopo, South Africa, using a metagenomics approach. Method: A total of 32 sample duplicates were collected from the influents (n=18) and the effluents (n = 14) from nine wastewater treatment plants (WWTPs) around the Vhembe region, Limpopo, South Africa. One hundred milliliter was filtered using sterile cotton gauze and Wattman filter paper to remove debris and membrane filtered through 0.22um membrane filters to capture the bacteria within each sample. DNA was extracted directly from the 0.22 μm filters using a DNA miniprep kit. DNA was quantified using a spectrophotometer. Shotgun 18 metagenomic sequencing was performed on DNA extracts. Open-source bioinformatics pipelines were used to process and analyze raw sequence data, uncovering information of the bacterial community composition and associated ARGs in wastewater. Results: Site observations reveal animal and human activities within and near the sites. ARG analysis revealed an overall number 0f 220 ARGs detected across the WWTPs. Thirty-six genes were common to influent samples and 16 in within effluent samples, encoding predominantly against macrolides, sulfonamides and tetracyclines, beta-lactamases, and aminoglycosides. Some unique ARGS were detected at sites near South African borders. Bacterial Diversity showed the predominance of some genera, such as Arcobacter, Aeromonas, Pseudomonas and Acinetobacter. Pathogens were predominantly enteric and pulmonary, with some being linked to animals in past studies. A notable increase in some members of Mycobactericeae, among other bacteria, was noted in effluents.
Open Access
AB INITIO and DFT computational study of Myristinin A and A structurally- related molecule
(2019-09-20) Tshilande, Neani; Mammino, Liliana; Ghio, Caterina
The computational study of biologically active molecules is particularly important for drug development because it provides crucial information about the properties of a molecule, which determine its biological activities. The current work considers the results of a computational study of myristinin A and a structurally-related molecule (2-(4-hydroxyphenyl)-4-[2,4,6-trihydroxy-3-(9tetradecenoyl)phenyl]-3,4-dihydro-2H-benzopyran-7-ol, here denoted as DBPO). The two compounds pertain to the class of acylphloroglucinols. They were firstly isolated from Horsfieldia amygdaline, and they exhibit a variety of biological activities, including potent anti-inflammatory activity, potent DNA-damaging activity and DNA-polymerase ß inhibition. Their molecular structures differ only by the acyl chain. Both molecules have a bulky substituent meta to the acyl group consisting of a ring system (2-(4-hydroxyphenyl)-3,4-dihydro-2H-chromen-7-ol). The DBPO molecule can exist as cis and trans isomers in relation to the double bond present in the R chain, and both isomers are here investigated individually. The OHs ortho to the acyl group can form an intramolecular hydrogen bond (referred to as the first IHB) with the sp2 O atom of the acyl group. The phenol OHs neighbouring the substituent ring system can form O–Hπ interaction with the aromatic rings of the substituent, if suitable oriented. This study focuses on the identification of the stable conformers of these molecules (considering all the possible geometries obtainable by rotations about relevant single bonds), and of the factors stabilising the conformers. Full-optimisation calculations were performed in vacuo and also in three conveniently selected solvents. The results show that the dominant stabilising factors are the first IHB and the O–Hπ interactions. Other factors which have significant influence on conformational preferences are the orientation of the ring systems of the substituent, the orientation of the OHs on substituent, the mutual orientation of the OHs of the phloroglucinol moiety and also the orientation of the acyl chain. The results in solution are consistent with the findings of other acylphloroglucinols, for instance, the narrowing of the energy gaps and the increase of the dipole moment with the increase of solvent polarity.
Open Access
Activity patterns, species composition and dietary analysis of bats on two macadamia farms in Levubu, South Africa
(2017-09-18) Mphethe, Vusani; Taylor, P. J.; Steyn, J. N.; Schoeman, M. C.
See the attached abstract below
Open Access
Adsorption of oxyanions of As, B, Cr, Mo and Se from coal fly ash leachates using A1/Fe modified bentonite clay
(2014-01-10) Masindi, Vhahangwele; Gitari, Wilson Mugera; Tutu, Hlanganani
Open Access
Alternative methods for solving nonlinear two-point boundary value problems
(2018-03-18) Ghomanjani, Fateme; Shateyi, Stanford
In this sequel, the numerical solution of nonlinear two-point boundary value problems (NTBVPs) for ordinary di erential equations (ODEs) is found by Bezier curve method (BCM) and orthonormal Bernstein polynomials (OBPs). OBPs will be constructed by Gram-Schmidt technique. Stated methods are more easier and applicable for linear and nonlinear problems. Some numerical examples are solved and they are stated the accurate findings.
Open Access
Alternative practices for optimising soil quality and crop protection for macadamia orchards, Limpopo Province, South Africa.
(2019-09-30) Steyn, Jakobus Nicolaas; Crafford, J. E.; Gliessman, S. R.; v. d. M. Louw, S.
The main aim of the research was to contribute means for converting conventional, high-input production systems to more sustainable ecological systems, thereby improving the sustainability of macadamia production and ultimately contributing to food security. This was achieved by a) investigating the potential use of cover crops and compost to enhance soil quality in macadamia orchards and b) investigating the potential use of use of cover crops and orchard heterogeneity to control stinkbug pests that target macadamia crops. Field experiments were conducted in three phases: phase one tested the potential of six cover crops for crop protection (as trap crops) and simultaneously for soil restoration or fertility enhancement purposes in macadamia orchards. Phase two repeated the trials of phase one (both soil restoration and trap crops) but with modifications to both categories. Soil restoration treatments were conducted with trees which were growing in what appeared to be healthy soils, and then repeated with trees in the same orchard where the topsoil had been degraded (totally removed) by agricultural operations. The third phase repeated the trap crop trials only, but this time on three different study areas (all commercial farms) with the single cover crop which performed the best as a trap crop during phase two. Trials were modified from the first to the last phase to overcome practical implementation problems encountered along the way and to adapt to local conditions experienced in the commercial macadamia farming systems which served as research sites. Diversity of natural orchard vegetation was enhanced in phase three to improve conditions for natural predators as part of the trap crop treatments in the last phase and cover crops were finally first composted and then returned to the root zones of the macadamia trees as part of the soil quality enhancement treatments in the second phase. The results from the trap crop trials shows a significant effect of trap crops combined with increased orchard diversity in reducing unsound kernel percentages caused by stinkbug pests and demonstrate that trap crops combined with an increase in orchard diversity could be utilized in macadamia orchards as a more sustainable alternative to inorganic pesticides against the stinkbug complex. The most notable changes in the soil that took place with soil quality enhancement treatments were the significant increases in soil phosphorous content and pH which resulted not in an improvement in soil quality in terms of these two indicators but revealed an important issue about the use of compost containing animal manure originating from dairies or feedlots. In summary however, it was clear that although not all the soil quality indicators that were employed to assess changes in the soil with compost treatments improved significantly, a holistic consideration of all indicators portrays an overall improvement which was particularly significant in the degraded soil plots where the topsoil had been removed by prior agricultural activities.
Embargo
An analysis of exposure and slope gradient impact on tree layer profile of Maroelakop vegetation in Nylsvley Nature Reserve, Limpopo Province, South Africa
(2024-09-06) Mavhila, Tendani; Tshisikhawe, M. P.; Magwede, K.
Since the 1850s, plant ecologists have been eager to investigate challenges in vegetation communities that are related to slope. The aspect of the slope is crucial in terms of the diversity and distribution of plants. This research was conducted on Maroelakop Mountain within Nylsvley Nature Reserve located in Mookgopong, Limpopo Province. The investigation aimed to assess and contrast the vegetation composition on the north-facing slope with that of the south-facing slope. The specific goals included ascertaining the density and frequency of dominant tree species on each slope, calculating the importance value indices of trees on both slope gradients and analyzing the population structure of the slope gradient. Point Centred Quarter (PCQ) was used in data collection. Shannon-Weiner diversity index, Simpson diversity index, and Evenness index were used to measure plant species diversity. In this study, a total of 600 trees were discovered and identified by their botanical names. The data represented 21 plant species in 17 genera and 12 families. The tree layer of the north-facing slope was dominated by Diplorhynchus condylocarpon, whereas that on the south-facing slope was dominated by Burkea africana. Both tree species had high-importance value indices. Shannon diversity index of 2.20 was obtained for the North-facing downslope, whereas the South-facing downslope had 1.74. The average Simpson diversity index for the North-facing slope was 0.82 and South-facing slope 0.77. The average Evenness index for the North-facing slope was 0.93 and, on the South-facing slope 0.81. This study concluded that Diplorhynchus condylocarpon is the most prevalent species within Maroelakop Mountain in the Nylsvley Nature Reserve.
Embargo
An evaluation of flood control mechanisms to withstand and adapt to flooding in Vhembe District, Limpopo Province
(2024-09-06) Munzhedzi, Lily; Nethengwe, N. S.; Mugari, M. E.
The Vhembe district is currently grappling with a rising prevalence of flooding, a phenomenon attributed to a combination of natural elements, such as heavy rainfall, and human-induced activities like deforestation and inadequate infrastructure management. The resultant damages encompass infrastructure destruction, loss of life, crop and soil damage, and environmental harm, with implications extending to human health, housing, livelihoods, government resources, and significant economic consequences. Consequences vary based on the resources and development levels of different areas, emphasising the need to understand each community's unique aspects for the development of resilient flood control strategies. The aim of this study is to evaluate the flood control mechanisms to determine if they can withstand and adapt to flooding in the selected study areas of Musina, Duthuni, and Sane in the Vhembe District. The study pursues two objectives: investigating trends in extreme rainfall and its relationship to flood occurrences, and characterising the nature, effectiveness, and adaptability of flood control mechanisms in the Vhembe district area. Employing a mixed-methods approach, the research design integrates both quantitative and qualitative methods to gain comprehensive insights. The data collection process involved the administration of in-depth questionnaires to participants, coupled with observational analyses of flood control mechanisms. This multifaceted approach allowed for a qualitative assessment of the nature, effectiveness, and adaptability of these mechanisms. Additionally, daily rainfall data sourced from the NASA POWER website was utilised. This data facilitated the computation of an average seasonal precipitation table, the generation of monthly precipitation figures, and tables displaying the count of days when precipitation exceeded the 95th percentile. The findings reveal a recurring pattern of precipitation throughout the seasons, with the highest average precipitation consistently occurring from December to February, and January emerging as a critical month for flood risk. The analysis of flood events spanning from 2000 to 2020 establishes a connection between daily rainfall exceeding 20 mm and instances of flooding, particularly evident in Duthuni, where nearly annual flooding has been observed. The study identified diverse flood control mechanisms linked to the level of development and community traditions. Natural and traditional measures, such as furrows and vegetation-based flood control mechanisms, dominate the rural village of Sane. In contrast, the urbanised Musina prefers engineered solutions like culverts and concrete channels, while Duthuni integrates both approaches. Furrows are popular at the household level across all the study areas, although their effectiveness is considered to be lower in comparison to other household flood control mechanisms. The field observational analysis emphasises the construction of flood control mechanisms using reinforced materials and underscores the importance of regular maintenance. The study underscores the importance of region-specific flood control solutions tailored to local conditions and preferences, considering climate patterns and community traditions. By adopting this approach, the Vhembe district can enhance its readiness and adaptive capacity for flooding. The study's results provide a foundation for well-informed decision-making and policy development, emphasising the necessity for initiatives to align flood management with the distinct challenges and preferences of local communities.
Open Access
Analysis of a boundary value problem for a system on non-homogeneous ordinary differential equations (ODE), with variable coefficients
(2015-01-16) Makhabane, Paul Suunyboy; Hlomuka, V. J.; Garira, W.
Open Access
Analysis of antibiotics and PFAS as potential emerging pollutants in the water bodies and their accumulation in food samples
(2021-04) Mpela, Ntshani Gershom; Tavengwa, N. T.
Antibiotics and perfluoroalkyl substances (PFAS) are groups of anthropogenic substances that are found in industries and consumer products, i.e., antibiotics are used in healthcare facilities, pharmaceutical companies, and agriculture, whereas PFAS are used in industries and households. These compounds find their way into the environment through emission, landfill disposal, agricultural run-offs, irrigations, leaching and wastewater spillage. Their residues are widely detected in almost every environmental compartment. Their detection in drinking water and food is one of the global concerns. Their effect in living organisms have been widely documented ranging from allergic reaction to carcinogenic effect, and in serious situations they can lead to death. In this project, the background review on the behaviour of antibiotics and PFAS in different environments are discussed in chapter two. This has been done by looking into their physico-chemical properties, distribution pathways, accumulation and toxicity in various environmental compartments through available literature. After understanding their behaviour in the environment two review papers, namely Paper I and Paper II, were written. Paper I was a book chapter which focused on the application of miniaturised liquid phase extraction techniques used for extraction of antibiotics in environmental water samples. In this book chapter, the use of liquid-liquid extraction techniques was discussed and the evolution of liquid-liquid extraction technique into miniaturised extraction technique was reviewed. Paper II was a critical review which focuses on the application of dispersive liquid-liquid micro-extraction of PFAS in different environmental samples. In this paper, the principles of dispersive liquid-liquid micro-extraction was explained. Later, its application for pre-concentration of PFAS was reviewed and the future trends were discussed. In chapter four, three lab-based papers, namely Paper III, Paper IV and Paper V, were written. In Paper III, for the first time a dispersive liquid-liquid microextraction technique was developed and applied for extraction of multi-class antibiotics in macadamia nuts prior to UHPLC-qToF-MS analysis. In paper IV, a novel deep eutectic solvent was synthesised and characterised using FTIR spectroscopy. For the first time the synthesised deep eutectic solvent was applied for extraction of multiclass antibiotics in green beans prior to UHPLC-qToF-MS analysis. In Paper V, for the first a dispersive liquid-liquid micro-extraction technique was developed and applied for extraction of PFAS in food contact materials prior to UHPLC-qToF-MS analysis. Owing to their ease of operation, efficiency and sensitivity, these techniques can also be applied for preconcentration of antibiotics and PFAS in different food, environmental and biological samples.
Open Access
Analysis of drought incidence, gendered vulnerability and adaptation in Chivi South, Zimbabwe
(2016) Chineka, Jestina; Musyoki, A.; Kori, E.; Chikore, M. R. H.
Climate change has brought about a number of global environmental challenges and the worst, climatic disasters such as floods and droughts. In Zimbabwe, particularly in the semi-arid Chivi District, droughts have become more frequent. At the household level, there are a multiplicity of vulnerability and coping mechanisms to this scourge, which have gender dimensions. This study analysed the vulnerability of the Chivi South community to drought and its adaptation with specific consideration to the gender dynamics. The specific objectives for this dissertation were to establish the characteristics and extent of drought occurrences in Chivi District in the last 30 years, assess Chivi South‟s vulnerability to drought, evaluate levels of gender vulnerability to drought, and analyse gendered adaptation to drought. Subsequently, a strategy for drought adaptation in the rural areas of Zimbabwe was drawn. The research was based on the mixed methods approach, as it employed both qualitative and quantitative approaches. Data collection methods included a review of official documents, key informant interviews with community leaders, Non-Governmental Organisations and government officials working in the area, household questionnaires and focus group discussions. The Standardized Precipitation Index was used to determine drought severity. Data was analysed using the SPSS 22.0 software. Capabilities such as Chi-square and cross tabulation were used to effectively analyse data. The Household Vulnerability Index was employed to infer vulnerability and adaptation of the community to drought. Research findings were illustrated using charts, graphs, tables and photographs. The study established the occurrence of droughts in Chivi, with a high prevalence of low magnitude droughts. A decrease in crop food production closely related to drought patterns was noted. Drought vulnerability cuts across the whole gender spectrum, with a sizable number of female headed households being severely exposed. However females adapt better to the effects of drought than males. A holistic approach which seeks to integrate both men and women in decision-making and to improve the community‟s adaptation to drought and other disasters was proposed
Open Access
Analysis of land use and land cover change and its impact on soil erosion in Nzhelele Valley, Limpopo Province, South Africa
(2022-07-15) Mavhuru, Blessing; Nethengwe, N. S.; Odhiambo, B. D.O.; Chikoore, H.
Globally, the rate of land use and land cover changes has affeceted the magnitude of soil eroion. Strategies to combat soil erosion can give assistance as solutions to provide food security in many agricultural areas. Although some changes are caused by natural factors, anthropogenic factors and an increase in population are major drivers of soil erosion. This study analyses land use and land cover change and its impact on soil erosion in Nzhelele Valley. To attain this goal, the objectives of this study are to classify land use and land cover change using GIS from 2005 to 2019 in Nzhelele Valley; assess the human influence of soil management strategies on soil erosion; determine the impact of soil fertility of different land use on soil erosion, and model soil erosion on different land-use areas of Nzhelele Valley. To select farmers, study used a stratified random sampling technique by dividing groups based on their villages. A systematic sampling technique was used to select 392 farmers. To collect 78 soil samples from Nzhelele Valley, the study used the Sampling Design Tool of ArcGIS 10.The study used supervised classification in Geographic Information System (GIS) to classify land use and land cover types. Semi-structured questionnaires were used to solicit data on human influence on soil management strategies on soil erosion. The study draws a systematic sample using Slovin’s formula to determine the size of the sample from the Nzhelele Valley, and with a target population size of 657 farmers from the village, 398 farmers were selected for the study. The study also measured soil organic matter, soil pH, phosphorus, and nitrogen from collected soil samples to determine the impact of soil fertility on soil erosion. To collect soil samples from Nzhelele Valley, the study used the Sampling Design Tool of ArcGIS 10. The tool assisted in selecting the soil sample points within the study area and a total of 78 soil samples were collected for the study. The Soil and Water Assessment Tool (ARCSWAT) with an interface of ArcView Geographic Information System software modelled soil erosion within Nzhelele Valley. In terms of LULCC, results show that from 2005 up to 2019, forest increased significantly by 5%, agricultural land cover significant decrease by 11% from 36% to 25% land use/cover, bare land built-up land increase by 3% from 14% to 17%, as well as grassland increase by 3% from 19% to 22%. The results also show a significant correlation (p < 0.05) between land use management strategies and economic support systems. The physical characteristics (slope and terrace) significantly correlate (p< 0.05) with soil management strategies that limit soil erosion. The results illustrate significant variation (p ≤ 0.0002) in nitrogen among different land-use classes. Significant variation was observed (p ≤ 0.0001) in soil pH, phosphorus, and organic matter among the different land-use areas. Changes in LULC are more likely to have an effect on soil erosion in the grassland and bare land/built-up areas where infiltration is very limited. The recorded decrease in agricultural land use and an increase in forest cover are likely to reduce the impact of soil erosion. Using SWAT to model soil erosion, 26-sub basin and 301 hydrological response units were delineated. The statistical elevation of the watershed obtained a minimum elevation of 384 m, maximum elevation of 1680 m with a minimum elevation of 808.81 m. Sub basins 13, 23, and 25 demonstrated high erosion-prone classes with average sediment yield of 15.3%, 11.26%, and 11.5% respectively. The lowest sediment yield (2.1 t/ha-1yr-1) in the study area was observed in sub-basin 3. Overall synthesis of the findings illustrates that research into land-use changes and type of land use activities factors were key aspects in addressing soil erosion challenges. These findings vibrate strongly on the need to develop a systematic land management system that can solve unplanned land cover and land-use change. Based on the results, fostering better management investments through collaborative land management in Nzhelele Valley might improve the dissemination of information. Farmer to farmer training can improve the skills of the individual, which might allow smooth dissemination of information vital for land management. The problem of soil nutrient deficiency can be a central issue put forward to the local government, which needs to be addressed with specific sectors of the government to create a better environment for agriculture and food security especially in the marginalized community of South Africa. Sediment output based on the land use classes is potentially influenced by cropland with the study. This allows for further solutions on the type of land use activities to be narrowed to understand the levels of soil erosion based on the activities. The study findings from this area can be used for comparison to other areas with the same characteristics to gain insight into possible solutions to the challenges of soil erosion.
Open Access
An analysis of patterns and trends of road traffic injuries and fatalities in Vhembe District, Limpopo Province, South Africa
(2016) Osidele, Olujimi Agbolahan; Nethengwe, N. S.; Dondofema, F.
Road transport safety is challenging globally, especially in developing countries, where it affects both road users and governments. The aim of road traffic safety is to ensure a reduction or total eradication of road fatalities and other injuries that are related to road accidents resulting from public road usage. In South Africa, one of the major problems faced by the Department of Roads and Transport is the issue of road traffic accidents. Between 2004 and 2010 the annual road traffic accidents increased to over 500,000 and 28,000 or more are fatal, which has led to serious injuries, as reported by the Department. This study analysed patterns and trends of road traffic injuries and fatalities in Vhembe District Municipality from January 2011 to August 2015. It also mapped road accident hotpots using Getis hotspot analysis and linear referencing in ArcGIS 10.2 spatial statistics extension. The research further established correlation between accidents spots and road design geometry. Factors that are responsible for road traffic accidents leading to fatalities, injuries, and loss of property were also examined. Pedestrian behavioural attitude towards adhering to road safety measures was studied using systematic random sampling, field observation and questionnaires. Finally, the study investigated if there has been any significant reduction in the road traffic injuries and fatalities occurrence rate within the last five years in Vhembe District since the commencement of World Health Organisation; Decade of Action for Road Safety 2011-2020. It was found out that most of the accidents occurred as a result of changes in human social behaviour, negligence and indulgence. The passenger road users category is the worst affected followed by drivers and pedestrians. It was found out that road crashes have decreased by 35% since the commencement of decade of action for road safety. The composition of road traffic injuries and fatalities since 2011 shows a reduction in the numbers of victims recorded. An average of 86 fatalities, 326 serious injuries and 701 minor injuries occurred per annum within the study period. There was high significant value (p  0.05) among all the categories of road users understudied. The differences observed were real and did not occurred by chance for the 5year period (2011 – 2015).
Open Access
Analysis of Peri-Urban Household Solid Waste Management System: A Case of Lwamondo Village
(2022-07-15) Nelwamondo, Fhumulani; Mudau, N. V.; Mokgoebo, M. J.
Peri-urban solid waste management has become a challenge caused by population growth, urbanization which increases the volume of waste generated into bulk quantities and change in the waste composition of solid waste generated, and neglect from a local municipality. It condones illegal disposal of household solid waste and improper use of waste management hierarchy which negatively affects the environment. The overall study examined the current peri-urban solid waste management system at Lwamondo village, with the specific objectives of the study include analysing the waste composition of solid waste generated; examine current solid waste management practices and analyse factors influencing current solid waste management, to achieve the objective of the study. Various quantitative and qualitative techniques were employed. Simple Random Sampling (SRS) technique was used as a sampling method, and 10% of the households in each sub-village were sampled for questionnaire distribution. The study also incorporated convenience sampling as a method for sampling households within 500m proximity to the illegal open dumping spots to conduct interviews. Using the designed checklist, field observation was undertaken for both households and illegal open dumping spots to identify waste composition. The study adopted a mixed-method integrating both qualitative and quantitative techniques. Using the field observation and checklist designed, findings confirmed that most of the waste generated are plastics and tin waste, rubble from demolition and construction activities, dead domestic pets, and metals waste. Due to lack of proper waste management plan, the community practice dockyard disposal, dumping, and burning waste which later have an empirical negative effect on the environment and their health. The study found that villages around the area lack waste management by-laws enforcement, lack of access roads, rapid population growth and urbanisation are the main identified factors influencing solid waste management. Based on the findings, the study recommends a nearby transfer facility and communal skin bins to cover residents, solid waste education and awareness to the community, recycling and reuse initiatives, establishment of formal buy-back centre, and waste composting.
Open Access
Analysis of soil erodability and rainfall erosivity on the Soutpansberg Range, Limpopo Province, South Africa
(2023-10-05) Kori, Edmore; Odhiambo, B. D. O.; Chikoore, H.; Van den Heever, S. C.
Soil erosion is a global challenge that threatens ecological functionality. The need for better soil conservation practices keeps growing due to the twin challenges of climate change and population growth. However, effective soil erosion management solutions remain elusive to practitioners due to the complexity of the soil erosion process. This is especially true for mountainous tropical regions which experience rainfall as high intensity thunderstorms accompanied by gusts of wind. Therefore, the aim of this research was to analyse soil erodibility and rainfall erosivity on the Soutpansberg range to establish the characteristics of the factors that influence soil erosion. The specific objectives were to classify geomorphic features of the Soutpansberg range; to characterise the spatial-temporal aspects of potentially erosive rainfall; to assess the influence of topography on wind speed and rainfall erosivity; and to compare rainfall erosivity derived from the USLE and the SLEMSA incorporating WDR erosivity. The classification of geomorphic features needed soil, hydrology, slope, geology and land-use-land-cover data. Soil data were obtained from the Harmonised World Soil Database (HWSD v 1.21) layer downloaded from The International Institute for Applied Systems Analysis (IIASA) online database. Additional soil data were obtained from field samples and splash cups. Hydrological data were downloaded from Department of Water Affairs, Forestry and Fisheries (DWAFF) website. Slope data were derived from the 30m pixel size SRTM DEM obtained from National Geo- Spatial Information (NGI). Geological data were downloaded from South African Geosciences online database. Land-use-land-cover were extracted from the South African National Land Cover 2018 dataset accessed online on the Department of Forestry, Fisheries and Environment website. Rainfall and wind speed data for the spatial-temporal characterisation of rainfall from 2000 to 2019 were obtained from the South African Weather Services. The data analysis followed different tools. Erodibility was assessed using GIS tools to combine the five factors to create a final soil erodibility map. Potentially erosive rainfall spatial-temporal characterisation section was done using spatial GIS interpolation and spatial autocorrelation. Spatial interpolation was achieved through co-kriging. Spatial autocorrelation was determined by the fusion of the coefficient of variation and the Moran’s I. The influence of topography on wind speed and rainfall erosivity was analysed through a Likert scale, simple linear regression and MANOVA. Finally, simple regression analysis and simple comparison were employed to establish the influence of wind on rainfall erosivity. This was treated from the wind free rain (WFR) and wind driven rain (WDR) perspective. The analysis produced the following results. The geomorphic classification for erodibility was based on intrinsic erodibility, landform position, slope position, geological setting as well as rain exposure. The factors operate on fourteen soil types found on the Soutpansberg range that fall into five granulometric groups. The erodibility maps for both USLE and SLEMSA, a result of a weighted sum overlay of all the erodibility factors, show high to very high erodibility on the south facing slopes of the mountain range. A large part of the range Analysis of Soil Erodibility and Rainfall Erosivity on the Soutpansberg Range, Limpopo Province, South Africa on the western part of the mountain range is classified as of very low erodibility in the SLEMSA method. The spatial-temporal characterisation indicates that rainfall on the Soutpansberg Range is very highly variable. The potentially erosive rainfall distribution is spatially dependent on the mountain range and the spatial variation mostly simple. Most rainfall is concentrated in the central areas of the south facing slope. The epicentre is located at elevations above 1200 m.a.s.l. However, rain days are dominated by medium spatial variability. The spatio-temporal characterisation mapping indicates that flash flood hotspots are in low to very low rainfall regions. This implies that high erosion areas are not defined by total rainfall amounts only because the temporal distribution of the rainfall is also important. Furthermore, the simple linear regression analysis revealed that elevation influences erosivity. In addition, hypothesis tests showed that wind speed and topography increase rainfall erosivity. Empirical data confirm that WFR and WDR erosivity are different. Wind Driven Rain computations where wind is above 2 m/s1 produce results similar to samples collected from splash cups. The research concludes that a deep understanding of the factors controlling soil erodibility is the foundation of effective erosion control. The soils’ intrinsic characteristics and raindrop exposure (represented by land use and land cover) explains more of variation in soil loss on the Soutpansberg mountain range. Furthermore, the mountain setting causes rainfall to be concentrated on the central south facing slopes at elevations above 1000 m.a.s.l. sending the very low potentially erosive rain zone to the western region of the mountain range. However, the highest peak of the mountain is in the western region. Erosion hazard potential is not confined to high rainfall zones only. Potentially erosive rainfall hotspots are located in low and very low rainfall zones. Furthermore, rainfall erosivity is not a function of rainfall amount only because topography increases both wind speed and rainfall erosivity. However, rainfall amount and wind speed are not correlated, and wind speed is not implied in rainfall amount. Nonetheless, wind speed is correlated with rainfall erosivity. Wind speed above 2m/s-1 increases rainfall erosivity. therefore, wind driven rain (WDR) erosivity is a better representation of rainfall energy than wind free rain (WFR). The research recommends soil erosion management approaches that also consider rainfall temporal distribution. In addition, further studies on rainfall spatial distribution need to be done using satellite-based rainfall data for more accuracy. Additional research on rainfall erosivity considering rainfall temporal distribution is necessary to identify erosion hazard zones. Intensive and extensive research on incorporating wind speed in the computation of rainfall erosivity can improve soil erosion estimation models. Analysis of Soil Erodibility and Rainfall Erosivity on the Soutpansberg Range, Limpopo Province, South Africa
Open Access
Analysis of the peak power of a photovoltaic array system under outdoor conditions at Vuwani Region of Limpopo Province
(2014-01-10) Nekhubvi, Vhutshilo 1st Mountaineer; Sankaran, V.
Open Access
Analysis of the solar radiation data and the determination of regression coeffients for Vhembe Region, Limpopo Province
(2012-12-11) Mulaudzi, Tshimangadzo Sophie; Sankaran, V.; Lysko, M. D.
Open Access
Animal taxa contrast in their scale-dependent responses to land use change in rural Africa
(2018-05-08) Foord, Stefan Hendrik; Swanepoel, Lourens Hendrik; Evans, Steven Wiiliams; Schoeman, Colin Stephan; Erasmus, Barend Frederik N.; Schoeman, M. Corrie; Keith, Martin; Smith, Alain; Mauda, Evans Vusani; Maree, Naudene; Nembudani, Nkhumeleni; Dippenaar-Schoeman, Anna Sophia; Munyai, Thinandavha Caswell; Taylor, Peter John
Human-dominated landscapes comprise the bulk of the world's terrestrial surface and Africa is predicted to experience the largest relative increase over the next century. A multi-scale approach is required to identify processes that maintain diversity in these landscapes. Here we identify scales at which animal diversity responds by partitioning regional diversity in a rural African agro-ecosystem between one temporal and four spatial scales. Human land use practices are the main driver of diversity in all seven animal assemblages considered, with medium sized mammals and birds most affected. Even the least affected taxa, bats and non-volant small mammals (rodents), responded with increased abundance in settlements and agricultural sites respectively. Regional turnover was important to invertebrate taxa and their response to human land use was intermediate between that of the vertebrate extremes. Local scale (< 300 m) heterogeneity was the next most important level for all taxa, highlighting the importance of fine scale processes for the maintenance of biodiversity. Identifying the triggers of these changes within the context of functional landscapes would provide the context for the long-term sustainability of these rapidly changing landscapes
Open Access
Ant and spider diversity in a rural landscape of the Vhembe Biosphere, South Africa
(2017-09-18) Mauda, Evans Vusani; Foord, S. H.; Munyai, T. C.
See the attached abstract below