Mundalamo, H. R.Ogola, J. S.Munyai, Phumudzo Gift2026-02-032026-02-032025-09-05Munyai, P.G. 2025. Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa. . .https://univendspace.univen.ac.za/handle/11602/3143PhD (Geology)Department of Earth SciencesPhytoremediation is an environmentally friendly technique that uses green plants to reduce, remove or extract environmental toxins, primarily those of anthropogenic origin, to restore sites to a condition suitable for private or public use. Its efforts have largely focused on the use of plants to accelerate the degradation of organic contaminants with root rhizosphere microorganisms or remove hazardous metals from the soils and water. Phytoremediation of contaminated sites is relatively inexpensive and aesthetically pleasing to the public compared to alternate remediation strategies which involve excavation or chemical in-situ stabilization. The Giyani Greenstone Belt is known for its gold mineralisation, and has been exploited at Klein Letaba, Louis Moore, Birthday, Golden Osprey and Fumani mines. All these mines are closed but the metals within their respective tailing’s dams can cause environmental and health problems. This study focuses on the Klein Letaba Tailings Dam which has metals such as Lead (Pb), Zinc (Zn), Copper (Cu), Arsenic (As), Nickel (Ni) and Cadmium (Cd) and traces of Gold (Au), which pose significant risks due to historical mining activities. Fieldwork involved geobotanical mapping, geochemical surveys, and pot culture experimental design. A total of 80 plants and tailings samples were randomly collected due to their dominance and abundance on the tailings dam. Tailings samples were collected at the same location as the plant samples. The samples were analysed at the University of Venda, Department of Earth Sciences, Faculty of Science, Engineering and Agriculture and Madzivhandila College of Agriculture. Pot-culture experimental design setup was conducted to evaluate the growth rate and metal uptake and accumulation by hyperaccumulating plant species at the South African National Biodiversity Institute (Thohoyandou Botanical Garden Nursery). The setup involved the use of 14 flower trays. This was done to mimic the Klein Letaba tailings natural environment. The duration of the experiment varied with the growth rate of the different plant species with an estimated period of 7 months for all plants followed by harvesting for four months. Metal concentrations of the plants and tailings were determined using inductively coupled plasma-optical emissions spectrometry (ICP-OES). Geochemical data analysis was done using Microsoft Excel, Arc GIS and Simple Kriging (SK) software to evaluate the metal distribution and plant metal uptake potential on different parts of the plant species at Klein Letaba tailings dam. The study identified three dominant native plant species: Combretum imberbe, Cynodon dactylon and Sporobolus africanus, which are naturally adapted to the tailings dam. Results revealed significant metal uptake, particularly in the roots of Combretum imberbe (CI), and Sporobolus africanus (SA). The metal concentrations of Pb, Ni, As, Cr, Zn and Cu in the tailings dam were found to be high, with a maximum of 11886 ppm, 2049 ppm, 1276 ppm, 1271 ppm, 695 ppm and 140 ppm respectively. The pot-culture experimental set-up constituted 4 harvests where Combretum imberbe demonstrated metal uptake for Cu, Pb and Zn, with concentrations in roots exceeding 7 ppm for Cu and 6 ppm for Pb. Sporobolus africanus showed notable accumulation of Cr, As and Pb with concentrations of 7.8 ppm, 6.6 ppm and 6.5 ppm respectively. Metal uptake was generally higher in the roots compared to the shoot and leaves, indicating that this species primarily acts as a stabiliser rather than a translocator of metals. The potential economic recoverability of metals from native plant species, such as Combretum imberbe, Sporobolus africanus, and Cynodon dactylon, was reviewed. The study identified Combretum imberbe as the most promising phytoremediator, recording high Zn, Fe and Cu uptake in the leaves and shoots, indicating potential for above-ground harvesting. Accumulation of Cu (~5 ppm), Zn (~8 ppm), and Fe (~10 ppm) make it viable for extracting economically valuable metals making it a potential candidate for phytomining. Combretum imberbe and Sporobolus africanus exhibited complementary potential for Zn recovery and stabilisation of Mn and Fe. Furthermore, the low concentrations of Cd and As uptake across all species suggest limited risk of secondary environmental contamination. Metals like Pb, Cu, Ni, Zn and Cd are economically valuable due to their market demand and can also be extracted by environmental remediation. Lead, for example, is currently valued at about $1.95 per kilogram, copper, $4.83 per kilogram, nickel, $7.11 per kilogram, manganese $1.55 per kilogram and zinc, $2.82 per kilogram. This research highlights the potential of native plant species to remediate and stabilise tailings environments while offering economically viable solutions through recovery of valuable metals. This environmentally friendly remediation strategy aligns with the global sustainability goals, fostering safer ecosystems and providing opportunities for rehabilitated land use in mining affected areas. Therefore, this remediation strategy is not only applicable in the studied site but can also be applied in other similar studies.1 online resource (xv, 219 leaves): color ilustrations, color mapsenUniversity of VendaPhytoremediationPhytominingKlein Letaba Tailings DamNative PlantsMetalsThesisMunyai PG. Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa. []. , 2025 [cited yyyy month dd]. Available from:Munyai, P. G. (2025). <i>Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa</i>. (). . Retrieved fromMunyai, Phumudzo Gift. <i>"Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa."</i> ., , 2025.TY - Thesis AU - Munyai, Phumudzo Gift AB - Phytoremediation is an environmentally friendly technique that uses green plants to reduce, remove or extract environmental toxins, primarily those of anthropogenic origin, to restore sites to a condition suitable for private or public use. Its efforts have largely focused on the use of plants to accelerate the degradation of organic contaminants with root rhizosphere microorganisms or remove hazardous metals from the soils and water. Phytoremediation of contaminated sites is relatively inexpensive and aesthetically pleasing to the public compared to alternate remediation strategies which involve excavation or chemical in-situ stabilization. The Giyani Greenstone Belt is known for its gold mineralisation, and has been exploited at Klein Letaba, Louis Moore, Birthday, Golden Osprey and Fumani mines. All these mines are closed but the metals within their respective tailing’s dams can cause environmental and health problems. This study focuses on the Klein Letaba Tailings Dam which has metals such as Lead (Pb), Zinc (Zn), Copper (Cu), Arsenic (As), Nickel (Ni) and Cadmium (Cd) and traces of Gold (Au), which pose significant risks due to historical mining activities. Fieldwork involved geobotanical mapping, geochemical surveys, and pot culture experimental design. A total of 80 plants and tailings samples were randomly collected due to their dominance and abundance on the tailings dam. Tailings samples were collected at the same location as the plant samples. The samples were analysed at the University of Venda, Department of Earth Sciences, Faculty of Science, Engineering and Agriculture and Madzivhandila College of Agriculture. Pot-culture experimental design setup was conducted to evaluate the growth rate and metal uptake and accumulation by hyperaccumulating plant species at the South African National Biodiversity Institute (Thohoyandou Botanical Garden Nursery). The setup involved the use of 14 flower trays. This was done to mimic the Klein Letaba tailings natural environment. The duration of the experiment varied with the growth rate of the different plant species with an estimated period of 7 months for all plants followed by harvesting for four months. Metal concentrations of the plants and tailings were determined using inductively coupled plasma-optical emissions spectrometry (ICP-OES). Geochemical data analysis was done using Microsoft Excel, Arc GIS and Simple Kriging (SK) software to evaluate the metal distribution and plant metal uptake potential on different parts of the plant species at Klein Letaba tailings dam. The study identified three dominant native plant species: Combretum imberbe, Cynodon dactylon and Sporobolus africanus, which are naturally adapted to the tailings dam. Results revealed significant metal uptake, particularly in the roots of Combretum imberbe (CI), and Sporobolus africanus (SA). The metal concentrations of Pb, Ni, As, Cr, Zn and Cu in the tailings dam were found to be high, with a maximum of 11886 ppm, 2049 ppm, 1276 ppm, 1271 ppm, 695 ppm and 140 ppm respectively. The pot-culture experimental set-up constituted 4 harvests where Combretum imberbe demonstrated metal uptake for Cu, Pb and Zn, with concentrations in roots exceeding 7 ppm for Cu and 6 ppm for Pb. Sporobolus africanus showed notable accumulation of Cr, As and Pb with concentrations of 7.8 ppm, 6.6 ppm and 6.5 ppm respectively. Metal uptake was generally higher in the roots compared to the shoot and leaves, indicating that this species primarily acts as a stabiliser rather than a translocator of metals. The potential economic recoverability of metals from native plant species, such as Combretum imberbe, Sporobolus africanus, and Cynodon dactylon, was reviewed. The study identified Combretum imberbe as the most promising phytoremediator, recording high Zn, Fe and Cu uptake in the leaves and shoots, indicating potential for above-ground harvesting. Accumulation of Cu (~5 ppm), Zn (~8 ppm), and Fe (~10 ppm) make it viable for extracting economically valuable metals making it a potential candidate for phytomining. Combretum imberbe and Sporobolus africanus exhibited complementary potential for Zn recovery and stabilisation of Mn and Fe. Furthermore, the low concentrations of Cd and As uptake across all species suggest limited risk of secondary environmental contamination. Metals like Pb, Cu, Ni, Zn and Cd are economically valuable due to their market demand and can also be extracted by environmental remediation. Lead, for example, is currently valued at about $1.95 per kilogram, copper, $4.83 per kilogram, nickel, $7.11 per kilogram, manganese $1.55 per kilogram and zinc, $2.82 per kilogram. This research highlights the potential of native plant species to remediate and stabilise tailings environments while offering economically viable solutions through recovery of valuable metals. This environmentally friendly remediation strategy aligns with the global sustainability goals, fostering safer ecosystems and providing opportunities for rehabilitated land use in mining affected areas. Therefore, this remediation strategy is not only applicable in the studied site but can also be applied in other similar studies. DA - 2025-09-05 DB - ResearchSpace DP - Univen KW - Phytoremediation KW - Phytomining KW - Klein Letaba Tailings Dam KW - Native Plants LK - https://univendspace.univen.ac.za PY - 2025 T1 - Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa TI - Phytoremediation of metals from Klein Letabs Gold Mine Tailings, Limpopo Province, South Africa UR - ER -