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Item Open Access Access and constraints to commuting in Gauteng Province, South Africa(2016-05) Chakwizira, James; Bikam, Peter; Adeboyejo, Aina ThompsonSee the attached abstract belowItem Open Access Analysis of Heavy Metals and Persistent Organic Pollutants in Sewage Sludge from Thohoyandou Wastewater Treatment Plant and transfer to Vegetables.(2018-05-18) Akinsaya, Nurudeen Akinwale; Odiyo, J. O.; Popoola, E. O.; Msagati, T. A.. M.Sewage sludge (biosolids) from wastewater treatment plants (WWTPs) has been widely used as a soil improver in Europe, United States of America and some developing countries including South Africa. It has its benefits for farmers as a good source of organic matter and minerals, however, sludge after treatment still contains pathogenic organisms, heavy metals and persistent organic pollutants (POPs). The POP and heavy metal contaminants that accumulate in sludge may transfer through the food chain and cause adverse effects on human beings. In this study, a field experiment was carried out on farmland fertilized with sewage sludge from a wastewater treatment plant (WWTP) that vasically receives domestic wastewater and storm water. Vegetable spinach (Spinacia oleracea) was used for this study and was planted on a farmland under controlled conditions. Ten ridges each of dimensions 20 m × 0.3 m was made and dry sludge weights of 5, 10, 15, 20, 25, 30, 35, 40, 45 and 50 kg were applied as manure on each of the ridges, respectively. Representative samples of sludge and soil were taken for analysis of heavy metals and POPs. At maturity, in twelve weeks, the root and leave samples of the vegetable were taken from all the ridges including the control. The soil, sludge, and vegetable samples were analyzed for total heavy metal content (Cd, Cr, Cu, Ni, Pb, Co, Zn, Al, Fe, Mn), speciated heavy metal content and POP (PAH, PCB). Soil and sludge samples were also analyzed for total organic content, pH, cation exchange capacity (CEC), conductivity and alkalinity. The analysis for total heavy metals and speciated heavy metal content was carried out using inductively coupled plasma optical emission spectrophotometer (ICP-OES), and CEC analysis was carried out using atomic absorption spectrophotometer (AAS). A two-dimensional gas chromatograph with time of flight mass spectrometry detector (GC X GC TOFMS) was used for POP measurements. pH measurement was made using a pH meter and conductivity measurement using a conductivity meter. Alkalinity and total organic content analysis was performed using titrimetric apparatus. The highest total heavy metal concentration of 378.9 mg / kg was recorded in Fe metal in soil and Leaf sample while the lowest total metal concentration of 0.0003 mg / kg was in Cu metal in root sample. The highest heavy metal concentration of 1002 mg / kg in speciated forms was in Mn metal in F1 fraction and the lowest of 0.0004 mg / kg was in Cd metal in F5 fraction. PAHs were only found in soil samples and their concentrations ranged from 2.53 mg / kg to 146.5 mg / kg. There were no PCB detected in all the samples analysed. The results indicated that the trace metals concentrations found in the exchangeable fraction were higher than those observed in any of the preceding extractions except in the case of Cd, Cr, Fe and Pb where Fe-Mn oxide and organic matter fractions predominated and were closely followed by exchangeable fraction.Item Open Access Analysis of work accidents data: A case study of the South African mining industry(2023-10-05) Masindi, Masala Theron; Amponsah-Dacosta, F.; Mhlongo, Sphiwe EmmanuelFor any industry to be successful, its production needs must be met while the highest safety standards are maintained. Mining accidents and their subsequent fatalities have enormous social and economic consequences. The current study was undertaken to better understand the fundamental causes of mine accidents so that major remedial actions can be developed and implemented to improve safety in the mining industry. The purpose of this study was to analyse work accident data of the South African industry that was compiled for the period 2008–2017. Secondary data on accidents was requested from the Department of Mineral and Energy Resources (DMRE). Accident data obtained from DMR was summarized, characterized, and described in a meaningful manner to determine the variables or factors which contribute to accidents in the mining industry. Variables that contribute to accidents in the mining includes fall of ground/rock fall, machinery, transportation and mining, general, conveyance accidents, electricity, fires, explosive, heat sickness and miscellaneous. Descriptive statistics, figures, and tables were used to describe and understand the accidents within the mining industry. A chi-square test was used to quantify the extent to which accident outcomes and commodities are independent of each other by year and injury type. This was done to examine the association between the dependent accident outcome and the independent variables such as year, commodity type, and casualty type. The study was significant in that its findings will contribute to building a culture of safety within the mining environment1, which was not only to reduce the risks of miners being exposed to potential workplace accidents but also had an impact on their attitude and perceptions towards workplace safety and their perception of zero as this is one of the priorities which the mining industries need to achieve. The study produced results that summarize the influence of year, commodity type, and casualty type on accident outcome. In particular, the analysis of accidents helped in establishing the relationship between the dependent accident outcome variable and several independent variables, such as year, commodity type, and casualty type, there was an increased number of accidents with respect to different commodities with different in years. The findings of this study vi will be used in planning, designing, and implementing health and safety programmes that will contribute to decrease in the number of accidents for mining different commodities in South Africa. Keywords: mining accidents, accidents dataItem Open Access Application of GIS and Remote Sensing techniques to evaluate the impact of land cover and land use changes on the hydrology and water resources of Luvuvhu River Catchment in Limpopo Province, South Africa.(2018-09-21) Singo, Lutendo Rhinah; Kundu, Peter Musula; Odiyo, John OgonyLuvuvhu River Catchment (LRC) exhibits diverse land use and land cover patterns that are influenced by seasonality and socio-cultural practices of the local communities. From 1950, the catchment has been undergoing land cover changes caused by expanding villages, new urban centres and clearing forest land for agriculture. Conversion of natural landscape for agricultural and urban purposes degraded the catchment by negatively affecting the hydrologic processes. This study was therefore conducted to evaluate the impact of land cover and land use change on the hydrology and water resources of LRC. Geographical Information Systems (GIS) and remote sensing techniques were applied to evaluate the impact of the changes on the catchment. Remotely sensed imagery was used as the primary sources of data for classification and detection of changes. Digital Elevation Models (DEMs) were used for hydrologic and geomorphic modeling in combination with information from remotely sensed imagery. Field data sets for soil and meteorology were obtained from selected sampling segments, based on the area frame sampling. The method of direct expansion was used to quantify land use classes. Flood frequency was analysed using probability distribution methods at recurrence intervals of 2, 5, 10, 20, 25, 50, 100, and 200 years. The FAO CROPWAT software based on Penman-Montheith equation was used to assess the impact of land cover changes on evapotranspiration regimes. To study the hydrological response of land cover change in the catchment, the Soil Conservation Services-Curve Number (SCS-CN) method was first used independently to simulate surface runoff and investigate the impact of land use change on runoff under historical land cover regimes. The Soil and Water Assessment Tool (SWAT) model was then applied in the Tshakhuma-Levubu subcatchment to assess the impact of land management practices on the soil and water bodies in the catchment. The results indicated that changes were having negative impacts on the hydrology of the catchment. The impact of land use and land cover change on hydrology of LRC was manifested in stream flow, surface runoff, suspended sediment and flood frequency and magnitudes. There was significant land cover and land use change from forestland, woodland and open grassland to medium size farms, subsistence agriculture and built-up land. These developments were concentrated on hillsides and hilltops in the catchment and they were of concern as they were ix impacting on the hydrological processes. Throughout the 2000’s, land use change revealed a decrease in natural forest from 32.15% to 20.67%, giving rise to agriculture which rose to 38.57% in 2010. Runoff was observed to be highly variable during the month of February with maximum runoff records of 1.63 m3 and 3.84 m3 upstream and downstream, respectively. Flood frequency results showed that an increase in the peak discharges was to be expected, especially for the discharge range corresponding to smaller and medium flood magnitudes. The use of imagery and DEMs within GIS was found to efficiently represent ground surface and allow automated extraction of features, thus bringing advantages in terms of processing efficiency, cost effectiveness, and accuracy assessments. This technique could therefore be adopted to improve land use planning, water management, and rapid identification of slopes and elevations in consideration for their functional and structural requirements. Analysis showed that the SWAT model was suitable for predicting the location and extent of pollution in the catchment. It assumed sheet and rill erosion as the dominant erosion type contributing to siltation and water pollution in rivers. The study recommends close monitoring and sustained enforcement of the rural land use regulations to prevent the conversion of land to urban land use.Item Open Access Application of smart value chain logistics for the small-medium brick manufacturing enterprises of Thohoyandou Town, South Africa(2023-10-05) Mawelewele, Lutendo; Chakwizira, J.; Ingwani, E.The study investigated the smart value chain logistics system application within the domain of the brick-making sector of Thohoyandou town, South Africa. The investigation has revealed new ways of re-imagining the operation of process inventory for produced and finished brick products from the supply chain to the distribution centers within rural towns through the utilization of Information and Communication Technology (ICT) platforms applied within the Small-Medium Brick Logistics enterprises. The Small-Medium Brick Enterprises (SMBEs) of Thohoyandou town consist of unlicensed small-scale enterprises and medium-scale enterprises. Little formal documented information was known about these enterprises in terms of the operational mode, production procedures, transportation, and socio-economic impacts on the host communities. The study aimed to demonstrate the application of the Smart Value Chain Logistics approach that could be applied to improve the transportation process in Small-Medium Brick Manufacturing Enterprises in Thohoyandou Town. The main objective was to recommend a smart value chain logistics framework. To analyze the value chain system that seeks to support the Small-Medium Brick Manufacturing Enterprises’ development in the brick-making sector of Thohoyandou town. The study analysis was conducted, where the sample size of the brick manufacturing enterprises in Thohoyandou town was 7 with (100%) responses. The sample size of the key informants from the local municipality and district municipality within the transport and housing departments was 5 with (100%) responses that were analyzed using the SPSS spatial analytical tool. The total sample size of all key respondents was 12. The research methodology selected for the study was the mixed method approach using qualitative and quantitative analysis approaches. The results revealed that the application of the smart value chain logistics framework approach could be adopted to improve the brick-making enterprise’s transport logistics in terms of operational efficiency, and effectiveness of the manufacturing activities.Item Open Access Assessing the use of wetting front detectors in water management at Dzindi Small Small Scale Irrigation Scheme in Limpopo Province(2017-04-18) Maduwa, Khathutshelo; Gumbo, J. R.; M'Marette, C. K.Irrigation uses the largest amount of water, estimating to 60 % of the total consumption in South Africa. For this reason, the efficient and reasonable use of water by irrigators is of paramount importance. Thus, this study was carried out to assess the suitability of Wetting Front Detectors (WFDs) in improving water management. The study involved an on-farm survey; field installations; testing of WFD technology on selected plots within the scheme; identification of the crops grown; documentation of the current water supply and documentation of the challenges faced by farmers in relation to irrigation. These were carried out to identify the ideal situations in the scheme. Irrigation scheduling helps farmers to know when to irrigate and amount of water required supplying for crop need. The study presented WFD, as a means of improving irrigation efficiency. The WFD is a simple tool that helps farmers to identify what is occurring around the root zone. Four plots with a representative farmer in each of the plot were identified in four Blocks (Block 1 farmer 1, Block 1 farmer 2; Block 2 farmer 1; Block 3 farmer 1 and Block 4 farmer 1). On-farm experiment of the WFD was carried out. However, with Block 4 farmer 1, insufficient data was collected due to absence of LongStop equipment. This also involved field installation, observation and measurements of the LongStops (LSs) and FullStops (FSs) WFDs at placement depth of 30 cm, 45 cm and 60 cm. The efficiency of an irrigation system depends on different performance indicators including Irrigation Efficiency (IE), Conveyance Efficiency (CE), Application Efficiency (AE), Storage Efficiency (SE), Distribution Uniformity (DU) and Coefficient uniformity (CU). In this study, attention was focused only on DU; CU and SE, as represented by water moisture availability. All the DU for all plots in blocks were below the standard DU of furrow, which is 65%. Farmer 2, in Block 1, had a higher DU and CU, which were 60% and 68%, respectively- considered closer to the standard DU value. For the other farmers, their DU and CU prior to irrigation were very low, which indicated that there was uneven distribution of water in these plots. The poor DU in Block 1 farmer 1, indicated by the uneven infiltrated water, resulted in excessive watering. Analysing the WFD showed that farmers were performed well in all the Blocks, except for farmer 1 in Block 1. Average soil moisture content result indicated high water loss through deep percolation. The highest volumes of water recorded before and after irrigation were 131 ml and 159 ml, respectively, for LS90 placed at a depth of 90 cm in Block 2 farmer 1. High volumes of water were collected in Block 1 farmer 2, Block 2 farmer 1 and Block 3 farmer 1 before and after irrigation. The result showed that, the more placement depth down the soil profile, the more accumulation of water in the LSs. Therefore, it was recommended that farmers continue to use the WFD as a tool for irrigation efficiency. However, there is need for improvement and capacity building in using the tool.Item Open Access An Assessment of Algae and cyanotoxins in small-holder Aquaculture farms in Vhembe, South Africa(2018-09-21) Tshifura, Rudzani Alice; Gumbo, Jabulani R.; Gitari, W. M.In South Africa, inland aquaculture is on the increase, especially among the rural communities. Thus aquaculture is able to provide a source of employment and improve rural incomes. This study assessed algae species and their cyanotoxins in small holder production in Vhembe district, Limpopo, South Africa. Thirteen study sites were selected to assess the algae species and their cyanotoxins. The water samples were collected in four quarters and analysed for water temperature, pH, total dissolved solids, Electrical conductivity, phosphates, nitrates, chlorophyll, cyanobacteria, cyanotoxins, metal species and quality of the water in the fish ponds. In the 1st quarter of the year there was variation in Water Temperature (23.7oC-31.4oC), pH (5.5-9.6), EC (3.82-46.8μS/cm), TDS (2.4-45 mg/L), Phosphate (0.0-1.09mgL-1), Nitrates (0.0-1.00mgL-1), Chlorophyll-a (5.8-11.5mg/m-3). In the 2nd quarter there was variation inwater temperature (22.4-25.0oC), pH (6.6-8.8.9), EC (19.23-21.47μS/cm), TDS (12.5-17.9 mg/L), Phosphate (1.64-1.84mgL-1), Nitrates (1.02-1.88mgL-1), Chlorophyll-a (4.6-15.6mg/m-3). In the 3rd quarter there was variation for water temperature (22.9-25.0oC), pH (7.5-9.1), EC (7.91-293.3μS/cm), TDS (11.7-180.9 mg/L), Phosphate (1.10-1.80mgL-1), Nitrates (1.28-1.84mgL-1),Chlorophyll-a (6.8-15.6mg/m-3). In the 4th quarter there was variation forwater temperature (23.5-30.3), pH (7.1-9.3), EC (18.24-623μS/cm), TDS (23.7-136.4 mg/L), Phosphate (1.45-1.99mgL-1), Nitrates (1.43-1.68mgL-1), Chlorophyll-a (6.6-25.9mg/m-3). The metal content of the fish pond water was variable throughout the year but with moderate levels of Al, Cd, Cr, Mn, Fe, Cu, Zn and Ba were found. The metal Fe, exceeded the DWAF guideline values during this first quarter. The presence of Cd in the fish pond water could be attributed to rainfall eroding the earthen embankments of the fish pond. The results of physico-chemical parameters promotes the growth of cyanobacteria in the fish ponds. Flow cam and SEM were used to identify the cyanobacteria species and most cyanobacteria identified are hazard to human health, fish and other aquatic organisms. Molecular technologies were used to identify cyanotoxins and there was no cyanotoxins detected which was concluded that during collection of water samples no cyanobacteria produced toxins.Item Open Access Assessment of health risk association with groundwater from Collins Chabane and Makhado Municipality of Vhembe District(2021-11) Mutileni, N; Edokpayi, J. N.; Enitan, A. M.Water is essential to life, but many people lack access to clean and safe drinking water, and many die of preventable waterborne diseases. The study conducted assessed groundwater vulnerability to Physico-chemical and microbial contamination across the Collins Chabane and Makhado Municipality. A three-set of samples (for metals, non-metals and microbial analysis) were randomly collected from twenty (20) primary schools, fifteen (15) private boreholes, and three (3) communal boreholes of Vhembe district, Limpopo province, South Africa. The physicochemical water quality parameters (pH, EC, and TDS) were measured using the YSI Professional Plus meter . At the same time, turbidity and salinity were measured using an Orbeco-Hellige portable turbidimeter and Extech multimeter, respectively. The physicochemical parameters measure in the field comply with the recommended standard set by South African Nation Standard SANS (2015) apart from the pH value detected in one sample collected in the wet season. Nitrate concentration (2.03–1532 mg/L) was obtained in high values in the most sample in the wet season. Some boreholes can have a noticeable taste due to chloride concentration (14.12–690 mg/L). The following metals Cd, Pb, Hg, As, Al, Mn, Fe, Co, Ni, Cu, Cr and Zn, Ca, K, Mg, and Na were analysed using an Inductively coupled plasma Mass spectrometer. The analytical results for major cations i.e., Ca, Mg, K and Na range between 14.20 – 349 mg/L, 11.40 – 309 mg/L, 0.49–12.80 mg/L, and 13.60 – 97.80 mg/L, respectively. The high concentration of Ca and Mg recorded in some of the sites exceeded the recommended limit set by DWAF (1996) and WHO (2015). The analytical results of heavy metal indicated that Ni (16.35 – 308.53 μg/L), Cr (27.46 – 72.84 μg/L), and Al (0.14 – 0.76 mg/L) were above the standard limits of SANS 241 (2015) in some of the sites. The membrane filtration method was employed to determine faecal indicator organisms. The results obtained for E. coli ranged between 0.0 – 76 cfu/100 ml in the dry season, while numerous values were detected for total coliform in both dry and wet season. All borehole failed to comply with SANS 241 and WHO standard limit in terms of total coliform while, 42.11% of borehole failed to comply with SANS 241 in terms of E. coli. Groundwater geochemistry was evaluated through Gibb’s diagram and Piper plot. The most dominant water type across all groundwater sample was Mg-HCO3 (40.79%, n=76) and Mg-Cl water type (38.16%, n=76) throughout the study period. Twenty one parameters (pH, EC, Cl-, NO3- , F-, SO4-2, HCO3-, Ca, Mg, K Na, Total Hardness as CaCO3, Cr, Mn, Co, Ni, Cu, Zn, Hg, Pb and Fe) were taken into consideration for the computation of water quality index (WQI). The WQI values of the selected school, household, and communal samples (50-103 and 25-101, 26-485 and 21-442, and 35-57 and 50-56, respectively) fell between the excellent to poor, excellent to unsuitable and excellent to good water based on the physico-chemical parameters used during dry and wet season, respectively. Some household samples had poor (21.43%), and unsuitable water (10.71%) during the assessment period. Nitrate was the principal element with enormously high concentrations that violated the WHO and SANS 241 permissible limit for drinking purpose which caused high levels of WQI. The source of contamination could be anthropogenic activities. Human health risk associated with the water quality parameters assessed was calculated using noncarcinogenic effects using hazard quotient toxicity potential (HQing), cumulative hazard index (HI) and daily human exposure dose (Ding) of drinking water through ingestion pathway. The computed non-carcinogenic effects (HQing) and HI for children and adult were ≥1 throughout the assessment. The main contributors to non-carcinogenic health risks in this investigation were Cr, Hg, and As. The carcinogenic risk assessment evaluated from selected heavy metals (Cr, Cd, Hg, Pb and As) exceeded the suggested potential risk limits apart from As and Hg for Adult in Dry season. Cr and Pb were above the carcinogenic indices of 1E-04 and 1E-06 throughout the season. Hence, these parameters can pose potential risk to both age group. Therefore, preventive measure should be implemented to prevent long term cumulative exposure risk. Quantitative microbial risk assessment (QMRA) was carried out to determine the risks of infection and illness due to consumption of groundwater. The estimation of QMRA indices values suggest that school boreholes had higher risk of infection than household and communal sites. Highest risk of infection has been detected during the month of November (wet season) in 2019. Only 30% school boreholes had an extremely high annual risk (90.52-100% probability) of E. coli infections to children. High probability values (90.5-100% probability) for annual risk of infection in all age group has been observed in 35.90% school samples throughout the assessment. Only 10.26% of school samples had annual risk of illness probability value of 35% in all age group. The annual risk of E. coli infections and illness was high in household site with 100% and 35% for all age group respectively. Meanwhile, 80.94 and 28.33% were the highest maximum values assessed for infection and illness in communal site. The estimation of QMRA indices suggest groundwater from the investigated study being a hazard. The methods of analysis in this study, suggested possible contamination of groundwater by anthropogenic activities such as small-scale agricultural activities, faecal contamination (pit latrines and septic storage), domestic waste on land, waste from concentrated livestock and natural processes such as microbial interference, weathering and dissolution. Preventive and mitigation measures to minimise such risks are indispensable.Item Open Access Assessment of impact of corporate social responsiblity on sustainable development of Shamva Mining Community in Zimbabwe(2016-05) Laisani, John; Amponsah-Dacosta, F.; Mhlongo, Sphiwe EmmanuelSee the attached abstract belowItem Open Access Assessment of Potential Temporal Impacts of “Land use Activities on Water Quality of the Luvuvhu River “Catchment, South Africa(2023-10-05) Shibambu, Thivhonali Hilton; Edokpayi, J. N.; Kahler, D.River health is crucial to benefit from the full resource potential of surface water bodies. This benefit becomes compromised when there’s high water quality degradation in the system. Considering the South African context, the use of untreated river water for domestic uses such as laundry, recreation, and crop irrigation, is a common practice in various urban and rural communities. The Luvuvhu River Catchment (LRC), in Limpopo Province, South Africa, serves as an essential water resource for the communities within the catchment. Thus, the main focus of this study was to assess the impacts of land use activities on the water quality of the Luvuvhu River Catchment (LRC). This was achieved by analysing the spatiotemporal variation of river water, sediment quality and the potential ecological as well as human health risks associated with the river water and sediments. Sediment and water “samples were collected from 22 sampling sites along” the Luvuvhu River Catchment between November 2020 and October 2021. Water samples were analysed for physicochemical parameters, nutrients, major metals and heavy metals, while sediments were analysed for heavy metals only. Physicochemical and nutrients data analysed consisted of pH, total dissolved solids (TDS), turbidity, temperature, dissolved oxygen (DO), salinity, biological oxygen demand (BOD), chemical oxygen demand (COD), electrical conductivity (EC), nitrate (NO3⁻), chloride (Clˉ), sulphate (SO4 2ˉ), and phosphate (PO₄³⁻). Samples were digested “using microwave acid digestion (EPA 3051) and analysed using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and inductively coupled plasma mass spectrometer” (ICP-MS) for major metals (Na, Mg, K, and Ca) and heavy metals (Mn, Fe, Al, Cr, Cu, Zn, As, Co, Ni, Mo, Ba, Hg, Cd, and Pb), respectively. The study examined the spatial distribution of these parameters using the Interpolated Distance Weighted (IDW) method on Esri ArcGIS Pro software. The findings were compared to South African Water Quality Guidelines and the World Health Organization. The results show that the water quality fluctuated during the sampling period. Some parameters such as turbidity, EC, nitrate, Al, Mn, and Fe exceeded the drinking water standards. The findings also show spatiotemporal differences in water quality. The upstream catchment of the river is predominantly covered by agricultural activities and land use becomes more naturally vegetated in the downstream catchment inside the Kruger National Park. Further, the study reveals that the Luvuvhu River Catchment receives a significant amount of pollutants from the upstream and midstream reaches as well as upstream rivers in the Limpopo River before the confluence of the Luvuvhu River. The quality of water further degrades towards the downstream catchment along the gradient as the river flows through various land use activities. It is therefore, concluded that upstream activities and other tributaries of the Limpopo River have a significant impact on the river’s water quality. The quality of water in some sampling sites are not suitable (higher than the Department of Water Affairs and Forestry guidelines) for agricultural use and protection of aquatic ecosystems due to elevated concentrations of some parameters such as Hg, Cu, Mn, Fe, and Al. Generally, about 72% of the metals in “sediments and water are higher during the wet season than the” dry season. It is also found that high runoff during the wet season act as a transporting mechanism for pollutants though some parameters are not seasonally influenced. The statistical tools used were able to analyse the water quality data of the river and provided meaningful and relevant information about the river. Multivariate Principal Component Analysis (PCA) revealed substantial anthropogenic contributions of metals in sediment and Cluster Analysis (CA) revealed three classes indicating three major anthropogenic (land use activities) contributions. While the “Pollution Load Index (PLI), Enrichment Factor (EF), Contamination Factor (Ci f) and Geo-accumulation Index (Igeo) indicate that the level of contamination is low to moderate in most of the” sediment samples. In consideration of “the potential ecological risk, the LRC sediments show low potential ecological” risk. Also, chronic daily intake of metals because of ingestion was below the recommended guidelines. The overall hazard index for children and adults did not exceed the recommended limit (HI < 1) indicating no or low health risk (non-carcinogenic). The carcinogenic risks of As, Pb and Cd at various sampling sites via ingestion were lower than 10-6 indicating no or low risk to develop cancer. This study recommends further studies to be conducted in specific time frames to limit heavy metal content and to prevent further pollution of catchment ecosystems including Kruger National Park by future industrialisation and urbanisation processes upstream of the catchment.Item Open Access An assessment of solid waste management practices in rural areas : a case study of Shigalo(2014-01-10) Simango, Thembi; Binala, J.Item Open Access Assessment of the contributions of air transportation in stimulating local economic development in Vhembe District(2016-02-10) Mutapanduwa, Simbarashe MorganItem Open Access Assessment of the Efficiency of Wastewater Treatment Facilities and the Impact of their Effluents on Surface Water and Sediment in Vhembe District, South Africa(2016-05) Edokpayi, Nosa Joshua; Odiyo, J. O.; Msagat, T. A. M.; Popoola, E. O.See the attached abstract belowItem Open Access Assessment of the use of ceramic water filters with silver nitrate as point-of-use water treatment devices in Dertig, North West Province, South Africa(2020-03) Ndebele, Nkosinobubelo; Odiyo, J. J.; Smith, J. A.; Edokpayi, J. N.Water borne diseases due to inadequate and unsafe drinking water is a global challenge that has led to a significant number of deaths and illnesses reported annually. These diseases are prevalent in less-developed countries, especially in rural areas where there is shortage of basic infrastructure and inadequate funds for piped water systems in individual households. Community members are forced to resort to collecting water from communal water points and later storing the water in containers for daily use. Recontamination of microbiologically safe drinking water during and after collection from the water source has been recognised as a problem; hence treating water at household level is one way to provide potable water for affected communities. The microbiological quality of household water may be improved by using point-of-use treatment technologies such as chemical disinfection, solar disinfection and ceramic water filters. Some of these technologies are expensive, less effective and difficult to implement in rural communities. This research thus focused on ceramic water filters and finding an appropriate method for silver application so as to produce filters that are effective in both the provision of clean drinking water and the release of silver levels that are safe for human consumption. An assessment of the efficiency of ceramic water filters made with silver nitrate as point-of -use water treatment device in Dertig Village, North West Province, South Africa was carried out. During production of filters made with silver nitrate, the filters undergo firing in an electric kiln and ionic silver is reduced to metallic nanopatches dispersed throughout the porous ceramic media. Both filters made with silver nitrate and conventional silver nanoparticles impregnated ceramic water filters were manufactured at the PureMadi Dertig Ceramic Filter Facility, South Africa. Resulting filters were evaluated and quantified for total coliform and E. coli removal as well as silver concentration in the effluent. Ceramic water filters made with silver nitrate had a high removal efficiency for total coliforms (94.7%) and E. coli (99.3%). A comparison of the performance of filters made with silver nitrate and silver nanoparticles in the provision of potable water was carried out and results showed that the different filters had similar levels of total coliform and E. coli removal, although the silver nitrate filters produced the highest average removal of 97.23% while silver nanoparticles filters produced the lowest average removal of 85.43%. Reasonable silver levels were obtained in effluent from all filters. Average effluent silver levels were 0.07±0.04mg/L, 0.6±1.10 mg/L and 0.8±1.0mg/L for 1 g, 2 g and silver nanoparticle filters, respectively (below the EPA and WHO standard of 100 mg/L). Because silver nitrate filters resulted in the lowest effluent silver concentrations, this could potentially increase the effective life span of the filter. A cost analysis of the process proved that it was cheaper to produce ceramic water filters using silver nitrate as the chemical can be purchased locally and also eliminates labour related costs. Thus, filters made using silver nitrate could potentially improve performance, reduce production costs, and increase safety of production for workers. The results obtained from this study will be applied to improve the ceramic filtration technology as point-of-use water treatment device in an effort to reduce health problems associated with microbial contamination of water stored at household level.Item Open Access An assessment of water quality of the wetland downstream of Makhado oxidation and its potential effects on irrigation waters(2016) Shibambu, C. S.; Gumbo, Jabulani; Gitari, W. M..; Pindihama, GlenWetlands are known of their pollution reduction characteristics due to their flat topography and dense vegetation which capture pollutants on the settling sediments. Three processes take place on the captured pollutants in the sediments, the physical, chemical and biological processes, which facilitate the removal of pollutants from the wetlands. This research was carried out in order to assess the Water Quality of wetland downstream of Makhado oxidation ponds and its potential effects on Irrigation Waters by determining the Physical-chemical parameters (pH, Dissolved Oxygen, temperature, electrical conductivity and turbidity); the nutrient levels (Nitrates, phosphates, nitrites, bromide) and heavy metals. The water samples were collected from the effluent discharge of Makhado oxidation ponds (upstream), the middle section of the wetland (midstream) and downstream of the wetland. The climate data for the study was also used assess the contribution to variation in the physical-chemical parameters during their passage through the wetland. The use of waters in the wetland by subsistence farmer’s was also assessed to determine their farmer’s perception on wastewater reuse, sustainability, water quality, health hazards and crop yield. At the discharge and midstream point, the physical parameters tested were found to be mostly outside the target water quality range of irrigation water set out by DWAF but are within the DWAF guidelines for discharge of wastewater. The exceptions were with total dissolved solids which were higher than 25 mg/l guideline value of the said standards. The anions were analysed by Ion chromatography and showed spatial variation in content and seasonality. The nutrients (nitrates, nitrites and phosphates) and chloride were higher than the DWAF guidelines for discharge of wastewater. The heavy metal content in the wetland was analysed by ICP-OES and varied throughout the wetland. The following metals were reduced during their passage in wetland and were within DWAF guidelines: zinc, lead, cadmium and total chromium. Iron and manganese were reduced during the drier season but were above the DWAF guideline values during the wet season. Also the metal contents in the wetland are out of the target water quality range of the same standards bringing forth the risks of toxicity in the wetland. The anion analysis also suggests that the wetland is becoming a nutrient rich environment bringing forth risks of eutrophication. Nitrite concentrations did not conform to the South African viii Water Guidelines on target water quality ranges for irrigation water. Farmers have expressed a positive opinion on wastewater use for irrigation since there are loads of nutrients. The presence of nutrients in wetland may contribute to development of harmful algal blooms.Item Open Access Bioprospecting of plants species with potential to uptake inorganic chemical species from gold mine tailings and acid mine drainage(2021-10) Makhado, Khumbelo Priscilla; Gitari, M. W.; Mudzielwana, R.; Dube, G.In South Africa, mining of gold and coal has huge negative impacts on the environment. This is due to the exposure of sulphide-bearing minerals such as pyrite (FeS2) to oxygenated water during and after the extraction of ore deposits which results in the formation of acid mine drainage (AMD). Acid mine drainage is characterised by low pH ranging between 1-4, high concentration of sulphate and chemical species which degrade the water quality and threaten the life of terrestrial and aquatic organisms. This study aims at bio-prospecting plant species with potential use in phytoremediation of AMD and gold mine tailings. First batch of samples of plants, water leachates and mine tailings were collected from Crown Mine within Witwatersrand gold fields in Johannesburg, South Africa while the second batch of samples of plants, water and sediments were collected from the mine water discharging points and within the AMD impacted wetlands streams in eMalahleni, Mpumalanga Coal Fields. In the first part of the study deals with the characterization of gold mine tailings and acidic mine leachates collected from crown mines in Johannesburg and further identification of plants species with potential for use phytoextraction of inorganic chemical species from the acidic leachates and gold mine tailings. The physicochemical parameters of leachates such as pH, electrical conductivity (EC), redox potential (Eh), total dissolved solids (TDS), dissolved oxygen (DO) and salinity were measured in the field using pH multi-meter. Elemental composition of mine tailings were analysed x-ray fluorescence (XRF) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) techniques. Leachates samples were analysed for metals contents using Inductively Coupled Plasma Spectrometry (ICP-MS) and anions using Ion Chromatography. Plant samples were digested using aqua-regia method and analysed with ICP-MS for elemental composition. The results showed that the mine tailings are mainly composed of SiO2, Al2O3, Fe2O3, MgO and K2O as major oxides and Cr, Co, Cu, Ni, Zn, Tb, Ta, Tm, Mo, Eu, Lu, Ho and Cs as trace elements. The pH, EC, TDS of the leachates were found to be ranging from 3.31 to 5.21, 3 857 to 5 517 mS/cm and 1930 to 2704 mg/L, respectively. The leachate samples were characterized by higher concentrations of Mn, As, Cr, Al, Pb, Ca, Na, K and Fe. The most dominating anions within the leachates were Cl- (135.97-201.28 mg/L) and SO42- (59.39-62.65 mg/L). Cortaderia selloana and Populus alba accumulated high concentration of Mn, Zn, P, Mg, K and B in their leaves than other parts of the plant. Translocation factor (TF) reflected that Cortaderia selloana plant species has the potential to translocate all the chemical species from the roots to the shoots except Se. Cortaderia selloana showed bioconcentration factor greater than 1 for chemical species such as B, Mn, Zn, Sr, Ca, Mg, P, and Si. Similarly, Populus alba showed the bioconcentration greater than 1 for Mn, Ni, Cu, Sb, Na and Mg. In addition, Populus alba showed bioconcentration factor greater than 10 showing hyperaccumulation ability for species such as B, Co, Zn, Ca, Cd, K, P and Sr. These plants can be used for the phytoremediation of mine tailings. Second part of the thesis focused on characterising mine water discharging from abandoned mine shafts and assessing the change in water quality from the discharging point, within retention ponds, upstream to downstream of the wetland. Furthermore, evaluating the role of sediments and native plants species in the remediation of acid mine drainage. The physicochemical characteristics such as pH, EC, TDS, Eh, DO and Salinity were found to be ranging from 2.53 to 3.6, 1066 to 2285 μS/cm, 610 to 5230 mg/L, 194 to 256.8 mV, 2.94 to 8.24 mg/L and 0.82 to 6.09 psu, respectively. The concentration of SO42-, Cl-, NO32- and F- were found to be ranging from 992.90 to 12580.38, 19.63 to 160.61, 1.77 to 23.56, and 4.76 to 14.95 mg/L, respectively. The dominant inorganic chemical species in water were found to be Ca, K, Mg, Na, Si, Al, Fe, Zn and Mn. The sediments collected along the streams showed higher concentration of Fe, Ca, Al, K, Mg, Na, P, Si, Zn, Mn, and V as compared to concentration in water. This implied that sediments are adsorbing chemical species from acid mine drainage and hence improve the quality of water. The concentration of metals in plants tissues are in the following order: Fe > Mg > Al > Mn > Zn > Cr > Ni > Cu > Co > Pb > As > Cd. Amongst all the native plant species, Cyperus esculentus had higher translocation factor (greater than 1) in Cr, Mn, Ni, Zn, Ca, K, Mg, Na, P and higher bioconcentration factor (greater that 1) in Cr, Co, Ni, Cu, and Zn, and a bioconcentration factor of greater than 10 in Cd, Ca, K, Mg, Na and P. This implied that Cyperus esculentus have the potential in phytostabilization of Cr, Co, Ni, Cu, Zn, and Cd, and Cd, Ca, K, Mg, Na and P and phytoextraction of Cd, Ca, K, Mg, Na and P. In nutshell, the results from this study showed all the plants species identified in this study (Cortaderia selloana, Populus alba, Cyperus esculentus, Phragmites mauritianus, Cynodon dactylon, Typha capensis and Juncus effussus and Juncus lomatophyllus) has potential for use in the phytoextraction of inorganic contaminants from the AMD and gold mine tailings. Therefore, the study recommends detailed studies optimizing the species application in phytoremediation of AMD and gold mine tailings in a pilot scale project.Item Open Access Characterization of potential acid leachate from raw coal, discard coal and slimes from Mafube Colliery : a replication to a proposed new extension, Mpumalanga Province, South Africa(2014-01-10) Novhe, Ntshengedzeni Obed; Ogola, J. S.; Maree, J. P.Item Open Access Coal Occurrence and Quality at Mushithe Area, Soutpansberg Coalfield, South Africa(2023-10-05) Mphanama, Thangeni; Mundalamo, H. R.; Ogola, J. S.South Africa is the 7th largest coal producer in the world and continues to rely on coal as its primary energy source, owing to its abundant availability and low cost. The Mushithe coal occurrence, located within the Pafuri basin of the Soutpansberg Coalfield, has been overlooked compared to other coal occurrences in the Tshikondeni area. The coal occurrence at Mushithe outcrops at Mbodi River. The study aims at establishing the geological setting, mode of occurrence, coal quality and economic value of the Mushithe coal occurrence. Geological mapping and sampling, petrography, and geochemical analysis were done on 14 host rock and 6 coal samples. Coal bearing rocks at Mushithe are occurring as a valley isolated from the Pafuri Basin. The outcropping seam at Mushithe is exposed along the Tshamatsha Fault. The coal measures contain four to seven seams, ranging from 0.35 m to 11.38 m in thickness. Pink and red quartzite, mudstone, basalt, quartz vein, sandstone, shale, carbonaceous shale, and calcrete were identified as associated rock types. The general strike is northeast, and the dip direction is northwest, with an average dip angle of 23°. Mushithe coal is dominated by vitrinite (65.77%) and inertinite (34.23%), with no liptinite detected. The high presence of vitrinite suggests that the coal is formed in a wet swamp environment. Additionally, signs of weathering such as cracks, fissures, and oxidation rims were observed in the coal. Coal quality belongs to bituminous C on UNECE 1998 classification, being characterised by low sulphur content (0.23 to 0.38 wt %) and high moisture (6.07 to 10.94 wt %), ash yield (16.7 to 41.9 wt %), volatile matter (29.7 to 35.8 wt %), fixed carbon (25.25 to 50.49 wt %) and calorific value (12.97 MJ/kg to 23.35 MJ/kg). Mineral matter constitutes approximately 5.7 to 35.8 wt %, predominantly quartz with varying proportions of clay (kaolinite), as well as minor carbonates (siderite) and sulphides (pyrite). The geochemistry is characterised by high values of Al2O3 from 7.56 to 15.83 wt %, SiO2 (9.76 to 20.04 wt %), and MgO (0.26 to 2.80 wt %). The outcropping seam was found to be of economic value and suitable for use as thermal coal for electricity generation.Item Open Access Community management of wetland ecology and socio-economic costs of wetland degradation in mudaswali Wetland, Limpopo Province, South Africa(2010-09) Sinyati, MollelSee the attached abstract belowItem Open Access Defluoridation of groundwater using vermiculite modified with hexadecyltrimethylammonium: a case study of Siloam Village, Limpopo Province, South Africa(2016-05) Ologundudu, Tayo Oladipo; Odiyo, J. O.; Ekosse, G. E.See the attached abstract below