School of Animal, Plant and Environmental Sciences (ETDs)

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A comparative analysis of mining environmental management programme reports following a change to the one environmental system
(University of the Witwatersrand, Johannesburg, 2022) Mathe, Lebogang; Watson, I.
The mining fraternity has recently seen a shift in terms of environmental requirements under the ambit of the Mineral and Petroleum Resources Development Act 28 of 2002 (MPRDA) to the National Environmental Management Act 107 of 1998 (NEMA). The objective was to ensure a streamlined environmental compliance and to put emphasis on integrated environmental management. The One Environmental System (OES) was introduced which denotes that all environmental related projects or activities, including mining, are regulated through an ambit of one system. NEMA is recognised as an overarching law which provides for co-operative environmental governance; therefore, all environmental related activities are regulated under its ambit and EIA regulations. In this research report, the Environmental Management Programme (EMP) reports and Environmental Authorisations that were issued under the MPRDA and the 2014 NEMA regulations respectively, were analysed using the respective regulations to compare the environmental management measures outlined in the reports to achieve better environmental results. The aim of the research was to assess whether the Environmental Authorisations granted in terms of NEMA reflect better environmental results as compared to those issued under the MPRDA. Better environmental results mean improved management plans with clearer assessment of impacts, more detailed mitigation measures with specific, achievable, relevant and time bound actions that do not pose harmful effects on the environment and communities. A mixed method of analysis was implemented which included a review and comparison of legislation, evaluation and scoring of 20 EMPs (10 submitted under MPRDA and 10 submitted under NEMA) and interviews with key informants, namely competent authorities and the Environmental Assessment Practitioners (EAPs) were conducted to support the findings of the reports. In conclusion, the reports analysed presented a significant improvement and better environmental results under NEMA. The interviews conducted with authorities and the EAPs have also substantiated the observations made in terms of Environmental Management Programme reports and Environmental Authorisations submitted. The findings indicated that there were similarities in the MPRDA and NEMA regulations as 4 | P a g e regards some environmental requirements. However, the MPRDA lacked to outline a detailed description of environmental requirements needed to manage environmental impacts. Thus, applicants provided limited information in terms of the management of impacts. NEMA has provided additional requirements, including baseline environmental information, specialist reports and public participation amongst others; these contributed to improved environmental results. The study revealed that the reports submitted under NEMA provided better environmental management measures as compared to the reports submitted under MPRDA.
An essential variable approach for integrated social-ecological systems monitoring to determine sustainability in a South African catchment
(University of the Witwatersrand, Johannesburg, 2024-05) Itzkin, Adela; Clifford-Holmes, Jai Kumar; Coetzer, Kaera; Scholes, Mary
This thesis presents an essential variable (EV) approach tailored for integrated social ecological systems (SES) monitoring within the Tsitsa River Catchment (TRC) in South Africa. The study addresses the conceptual and methodological challenges inherent in SES integration and monitoring to provide insights into sustainable landscape management. The research methodology employed a transdisciplinary social learning process, integrating systems thinking and participatory research methods across three related publications. In the first publication, systems diagramming, qualitative interviews, and participatory data collection provided a systemic snapshot of the interconnected social and biophysical drivers of land degradation in the TRC. The findings underscored the dual benefits of changes in land use and grazing practices for landscape improvement and sustainable livelihoods, informing the identification of monitoring variables crucial for sustainable land management. In the second publication, a social learning process, termed participatory self-observation, explored approaches to enhance integration and monitoring of biophysical and social data for adaptive management. The process identified data integration, overload, scale, learning oriented monitoring, and relationship-building as key challenges in SES monitoring Recommendations included participatory approaches focusing on applied work, identifying essential data for SES monitoring, and improving transdisciplinary collaboration. In the third publication, a transdisciplinary process guided by EV development identified Essential Social-ecological System Variables (ESEVs) for the TRC, emphasising the relational connection between social and ecological aspects of SESs. ESEVs were prioritized based on essentiality scores and participant consensus, facilitating integrated planning and management at the catchment scale. The ESEVs identified for the TRC include 'soil erosion related to human actions on the land,' 'participation in natural resource governance,' 'grazing and rangeland sustainability,' and 'land cover and condition. Participants proposed three additional ESEVs, 'access to water,' 'local natural resource governance system,' and 'human well-being in the landscape'. The study concludes that collaborative learning informed by diverse transdisciplinary perspectives can guide adaptive monitoring approaches, with lessons from the TRC applicable to diverse contexts. The ESEV approach offers wider application value, addressing the question of the minimum variables needed for integrative landscape management in complex SESs. Overall, this thesis pioneers a transdisciplinary mixed-methods approach for efficiently monitoring social-ecological sustainability outcomes. Through advancements in conceptualizations of integrated, contextually grounded monitoring, it offers a novel perspective for understanding the implications of development interventions, bridging critical gaps in SES monitoring.
An ethnobotanical study of indigenous knowledge of the medicinal plants used by traditional healers in the rural communities of Nkomazi Local Municipality, Mpumalanga province
(University of the Witwatersrand, Johannesburg, 2024) Khoza, Nompendulo; Dukhan, Shalini; Ramalepe, Phillemon; Risenga, Ida
Traditional medicine continues to significantly impact many people’s lives amid all the advancements in modern medicine. Many rural communities in Mpumalanga province depend on indigenous traditional medicines to manage various ailments. The available research on the traditional usage of medicinal plants among rural communities in Mpumalanga is highly fragmented and under-researched. The decline of medicinal plant populations has led stakeholders to take various initiatives to counteract over-exploitation, including cultivation as a viable conservation approach. However, the scientists' inadequate understanding of the acceptance of cultivated medicinal plants by traditional healers is one of the issues contributing to the failure of medicinal plant cultivation programs. Consequently, this study aimed to document medicinal plants utilised by the Nkomazi Local Municipality's traditional healers and assess opportunities and constraints for medicinal plant conservation in the Nkomazi Local Municipality. The ethnobotanical data was obtained through semi-structured questionnaires and guided field walks with traditional healers. Individual interviews were conducted with ten traditional healers from eight villages across Nkomazi during field visits between July 2021 and February 2022. The study employed qualitative and quantitative approaches to understand traditional healers' perspectives concerning the ethnobotanical significance and medicinal plant conservation. The study found that the indigenous knowledge of medicinal plants in the Nkomazi Local Municipality is diverse, encompassing 111 species from 59 different families employed to treat 70 ailments. Most of the reported medicinal plants for this study are of Least Concern. Additionally, the top fourteen most reported species in the Nkomazi Local Municipality included commercially valuable plants such as Psidium guajava, Ricinus communis, Sclerocarya birrea, Aloe ferox, Aloe maculata, Leonotis leonurus, and Moringa oleifera. Most of the Nkomazi Local Municipality's traditional healers did not know about protected plant species and the National Environmental Management Act (NEMA). Traditional healers were aware of the decline in wild populations of medicinal plants, which they attributed to various factors such as overharvesting. Diviner’s and herbalist perception of using cultivated plants did not differ significantly (𝜒2=0.4762, df=1, P= 0. 490). The study provided a comprehensive inventory of medicinal plants utilised by Nkomazi traditional healers and essential data for future assessments of the use local use of indigenous medicinal plants.
Assessing habitat selection of grassland rodents in the Cradle of Humankind
(University of the Witwatersrand, Johannesburg, 2024) Pinto, Catiuscia-Jade; Mackay, Megan; Pillay, Neville
Habitat selection is a decision-making process undertaken by animals to select an appropriate environment suitable for fulfilling their survival and reproductive needs. These decisions are driven by a complex of biotic and abiotic factors. Habitat selection relies on how an animal interacts with its environment and is species-specific. The vegetation structure and composition influence how smaller animals, such as rodents, obtain food and cover, and are thus critical for their survival. The aim of my study was to assess the population demography and habitat selection of nocturnal rodents in two grassland sites located within the Cradle of Humankind Nature Reserve, Krugersdorp, Gauteng Province, South Africa. I obtained rodent data using Capture-Mark-Recapture (CMR) methods, and vegetation data were obtained through randomised quadrate sampling. The following six rodent species were sampled, Gerbilliscus leucogaster, Lemniscomys rosalia, Mastomys coucha, Micaelamys namaquensis, Mus minutoides and Otomys angoniensis. Rodent abundance differed between summer and winter, with winter showing a higher abundance, but richness and diversity indices did not differ significantly between sites or seasons. The three most common species, G. leucogaster, M. coucha and O. angoniensis, were selected for further population demography analyses. The demography of G. leucogaster, was mostly associated with the season since seasonal fluctuations were observed in their population size (higher in summer), reproductive activity (more active in summer) and body condition (higher in winter). Mastomys coucha was the most abundant species in the study, since it had the highest number of sampled individuals in both summer and winter, although its demography was not influenced by external factors (e.g.,, season, vegetation height, vegetation cover) recorded in both summer and winter. Otomys angoniensis had a positive relationship with vegetation height and rodents’ body condition. The three species were able to coexist with one another due to differences in foraging strategies, reproductive strategies, spatial and dietary partitioning, which help to facilitate habitat selection and illustrate that habitat selection is species specific. Key words: Rodents, habitat selection, Gerbilliscus leucogaster, Mastomys couch
Assessment of the Environmental Authorisation Processes and Mining Right Applications for Improved Environmental Outcomes
(University of the Witwatersrand, Johannesburg, 2023) Antoniades, Maria; Watson, Ingrid
This study investigates alignment of South African mining right and environmental authorisation application processes to determine their adequacy in catering for optimised early mine planning seeking to achieve enhanced environmental outcomes. First the legislative requirements for mining right and environmental authorisation applications are evaluated. Results are critically analysed, including an assessment of process alignments and disjunctions. Secondly, integration of the application study processes in practice are investigated. The practical implications of the application requirements are qualitatively examined through key informant and case study analysis. It is shown that integrated planning is not a legislated requirement nor readily adopted by proponents. Environmental planning conforms to technical outputs as tick-box exercises rather than being iterative and co-operative. Workstreams misalignments result in poor planning to the detriment of environmental outcomes. Finally, a practical guidance is presented for early integrated study processes aimed at meaningful project design through parallel planning to optimise environmental results.
Biodiversity stewardship in south africa - an assessment of the klipkraal biodiversity stewardship programme and its potential for conservation
(University of the Witwatersrand, Johannesburg, 2024) Butler, Kirsten
The importance of conservation in agriculture has become more apparent over the last couple of years, however it involves complex social-ecological relationships and as agriculture is a critical industry for human survival, biodiversity conservation in the industry is a major challenge worldwide. In South Africa, biodiversity stewardship programmes, which involve agreements between landowners and conservation authorities to secure land in biodiversity priority areas, are becoming a prominent method of conservation in agriculture. Yet there is a lack of research on the conservation benefits and whether they show improvements in the area’s biodiversity. This study focussed on the Klipkraal biodiversity stewardship programme which consists of two privately owned functional cattle farms in a peri-urban area of the southern grasslands of Gauteng making up 2 656 hectares of land of which 1 600 hectares are natural vegetation, and the remaining area is cultivated land used for farming maize and soya. The study sought to answer the question: what is the ecological state of the area and does this programme have potential for conservation in the long-term? The aim of this study was to assess the potential conservation benefits and sustainability of the Klipkraal biodiversity stewardship programme. The study involved both qualitative and quantitative data collection, including landcover mapping, field surveying to assess the vegetation state and mammal diversity and distribution of the site, and interviews with key stakeholders. The landcover mapping allowed for a visual representation of the various landcover types and percentage coverage of each of the six landcover types found in the study area. Vegetation assessments at five different sites resulted in an understanding of the vegetation structure, composition and cover across the two farms and from this it was established that the vegetation structure and species diversity differ, but the species composition is similar throughout the study site. An anthropogenic disturbance score was allocated to each site and the highest rated anthropogenic scores correlated with the sites consisting of the highest exotic species. The mammal assessments showed that the varying vegetation structure allows for specialist species to occupy a range of habitats within the site and also indicated that there are barriers to the movement of large mammals within the site. The results of the vegetation and mammal assessment which suggest a diverse range of vegetation units, habitats, and mammal diversity, emphasise that the area is important for conservation. The interviews revealed the multiple challenges involved in the Klipkraal Biodiversity Stewardship Programme and requirements in order for the programme to be successful in the long term. These include a need for willingness of landowners to put their time and resources into conservation efforts on their properties, a need for constant monitoring of management strategies, the importance of expanding the stewardship areas to ensure conservation of the entire area and not just isolated fragments of the area. However, key challenges in expanding the programme were also revealed, such as scepticism by landowners in entering land agreements with the government and in Gauteng, many areas of conservation interest are made of multiple small properties that are owned by different landowners which means a lot of effort is required in getting each landowner to sign up. Insight was also given into the roles of the various stakeholders and the relationship between the Gauteng Department of Agriculture and Rural Development (GDARD) and the landowners, and it was indicated that GDARD’s role is to provide guidance, education and resources when available to the landowners in order to manage their protected area. This study can be used as a baseline study for GDARD to measure the progress in conservation in terms of the landcover and ecological aspects at the site and to monitor any changes in landowner-GDARD dynamics.
Characterisation of Drought Using Hydrological and Meteorological Indices: A Case Study of Bethlehem, South Africa
(University of the Witwatersrand, Johannesburg, 2023) Tshabalala, Khanyisile; Evans, Mary; Masindi, Khuliso
The study aims to assess the severity and evolution of drought/s in Bethlehem using the hydrological: Streamflow Drought Index (SDI), Reconnaissance Drought Index (RDI), Effective Reconnaissance Drought Index (eRDI) and meteorological: Standardised Precipitation Index (SPI), Agricultural Standardised Precipitation Index (aSPI), and Precipitation Deciles (PD) indices. These indices were computed using the Drought Indices Calculator (DrinC). The RDI, eRDI, aSPI, and SPI identified three drought events between 1980 and 2017. The PD on the other hand, identified particular years between 1980 and 2017 that received below-normal to much below- normal precipitation. Further, the years identified to have received below normal to much below normal precipitation fell between the drought periods identified by the other indices, such as the 1980 – 1990 drought identified by the SPI, RDI, aSPI, and eRDI; the PD identified 1982, 198, 1985, and 1986 as specific years the received significantly low precipitation within the decade long drought. Of critical note is the absence of the SDI results, stream levels data was not available at the time the results presented in this report were computed. The unavailability of SDI values did not compromise or negatively affect the results presented in this study as the computed indices had a strong correlation, implying the reliability of the results presented in this report
Characterizing microclimates as potential thermal buffers for reptiles, birds, and mammals in an arid-zone environment
(University of the Witwatersrand, Johannesburg, 2023) Warner, Grace M.; Alexander, Graham J.; Fuller, Andrea
Aridification, increases in air temperatures and frequency of extreme weather events, such as heat waves, are predicted to intensify under climate change, suggesting dire consequences for dryland animals. Microhabitats may buffer dryland animals against the changing climate, yet microclimatic data remains scarce from Africa and arid regions. The distribution, abundance, and thermal buffering capacity of five microhabitat types (burrows, nests, rock crevices, tree hollows and vegetation) were investigated across three habitat types (dunes, plains, and mountains) in the Kalahari. The distribution and abundance of microhabitats were assessed via strip transects, while thermal buffering capacity was evaluated by comparing miniature black globe temperatures from 70 representative sheltered microhabitats with 12 localised exposed-site microhabitats. The data generated have provided a baseline measure of the abundance and distribution of microhabitats in the Kalahari and have produced a year-long fine-resolution microclimatic thermal dataset. Microhabitat types and abundance were found to differ per habitat type and across topographic gradients. Abiotic drivers, such as soil type and fire frequency, along with drivers such as biotic community composition, were highlighted as potential causes of these microhabitat distribution patterns. Burrows were the best buffered microhabitat across all tested temporal and spatial gradients, providing an average maximum decrease of -29.5 ˚C during the day, and an average maximum increase of 20.1 ˚C during the night. Well-buffered microhabitats were rare within the field-site, whereas some of the poorest buffering microhabitats (Vegetation) were abundant and widespread. Thus, competition for well-buffered microhabitats may increase under climate change, whilst the risk of traversing large distances between microhabitats may become too great for smaller animals as exposure risk to extreme temperatures increases. Furthermore, birds and large mammals may likely be at a high risk of extreme temperature exposure, as their size and structural adaptations may restrict them from access to well-buffered microhabitats. Therefore, the need for the concurrent assessments of microhabitat distribution, abundance and buffering capacity in future species vulnerability assessments is highlighted, as it is the combination of these factors that are likely to impact population viability under climate change.
Cognition in urban-dwelling yellow mongoose, Cynictis penicillata
(University of the Witwatersrand, Johannesburg, 2024) Muller, Mijke; Pillay, Neville
Cognition involves perceiving and processing environmental cues and devising appropriate behavioural responses to act on the acquired information. Studying animal cognition in an urban setting provides insight into the occurrence of behavioural changes in urban-adapted animals. This thesis aimed to investigate the cognitive abilities of a population of yellow mongoose, Cynictis penicillata, inhabiting locations with differing extents of urbanisation in South Africa. First, I investigated whether mongooses could learn to solve a puzzle box problem of increasing complexity. The mongooses were able to solve the problem at each stage of complexity, but took longer in a residential ecological estate than those frequently visiting a residential garden. These results indicated that mongooses were capable of innovation, but their problem-solving abilities were influenced by the level of disturbance in their environment. Secondly, I investigated whether mongooses exhibited cognitive flexibility. The mongooses were able to inhibit a non-rewarding behaviour, even when it was previously rewarded, in favour of a newly rewarded behaviour during the puzzle box task. Additionally, they could solve the puzzle box problem during distraction, but took longer with the most distraction, likely splitting their attention between solving the problem and remaining vigilant. Combined, the mongooses were capable of reversal learning and divided/alternating attention, providing evidence of cognitive flexibility in this mongoose population. Thirdly, I investigated the effects of a direct human approach on the problemsolving ability of mongooses. In areas of heightened human disturbances, the mongooses had reduced tolerance to humans, but were equally efficient at solving the puzzle box problem following human disturbance than those in areas of reduced human disturbance. Those more tolerant of humans improved their problem-solving efficiency, likely adapting to the disturbance. Finally, I investigated whether mongooses experienced a paradox of choice (i.e. whether too much choice can be cognitively challenging). The mongooses in my study appeared to experience cognitive difficulties when presented with extensive choice, providing support for a paradox of choice. These results provide evidence that urban-living yellow mongooses’ successful adaptation to an urban habitat may be attributed to their cognitive abilities, allowing them to exploit novel resources and flexibly adapt to the rapid environmental changes associated with urbanisation. However, the disturbance associated with urbanisation may negatively affect problem-solving efficiency, which may impact successful food acquisition, and the increased availability of resources may be cognitively challenging for urban-living yellow mongooses.
Comparative Analysis of Water Hyacinth Efficiency as Biosorbent and Phyto remediating Plant for Removal of Lead (Pb) Water Contaminants
(University of the Witwatersrand, Johannesburg, 2023-08) Nwagbara, Victor Uzoma; Parrini, Francesca; Newete, Solomon
One of the major problems facing the modern society is the issues of water contamination. The ability of aquatic plants to serve as both heavy metal biomarkers and phytoremediators has been advocated for many years. The purpose of this study was therefore to compare the efficacy of water hyacith as a biosorbent and phytoremediating plant for removal of lead from contaminated waters. Dry and fresh water hyacinth biomass were exposed to Pb-contaminated water at different time intervals of 1, 7, 14 and 21 days. The results showed that with the increase of the exposure time, the Pb removal capacity of the plant biomass also increased. The Pb water concentration in day 1 and day 7 were significantly different from those in day 14 and day 21 which were not significantly different from each other. The average Pb removal from the Pb-treated waters for the different time exposure of 1, 7, 14 and 21 days in the fresh water hyacinth biomass were 40%, 56%, 78 % and 79%, respectively, the highest reduction being in the latter. The biomass of the freshwater hyacinth roots had the highest Pd concentration compared to the shoot. On The other hand the average Pb removal by the dry water hyacinth biomass were 78.9 %, 78.5%, 78.3 % and 78.3% for day 1, 7, 14 and 21 respectively, showing no significant difference between the different time series exposure. This suggests the instant adsorption of Pb by the dry plant material from the first day of exposure, after which the active sites for adsorption saturates to accommodate any further Pb ion uptake. There were some plant stresses such as leaf chlorosis, and significant decrease in biomass weight and length of leaf-2 petiole in the lead-treated fresh water hyacinth plants compared to the controls (Pb-free water hyacinth plant). Thus, this study confirms that the largest removal by the dry water hyacinth biomass, occurred in the first day as opposed to the last day (day 21) by the freshwater hyacinth biomass.
Eco-art for a transformative climate culture
(University of the Witwatersrand, Johannesburg, 2022) Warrington-Coetzee, Hannelie; Voge, Coleen; Manderson, Lenore
Human”‘development” since the industrial revolution has unequivocally attributed to a code red of climate disasters, according to the recent IPCC Sixth Assessment Report of the Intergovernmental Panel on Climate Change report (IPCC, 2022a). To selectively unlearn or de-grow the unsustainable industrial culture crisis, humanity needs seriously to consider and act to transform (e.g., through ecocitizenship) in support of governments, scientists, and other civic actions in our journey to sustainable futures. Using a transdisciplinary praxis approach, artists can provide various forms of transformative possibilities, including transgressive interventions at a grassroots level, deliberately designed to provoke and inspire change. This research interrogates how eco-art deeply engages audiences to identify the key characteristics of such potentially radically transformative artworks. Humans have a narrowing window to transform our relationship to the Earth’s resources and reverse or slow temperature rise. The ‘near term’ (2022 – 2030) will determine and define the extent of various climate transformation pathways (IPCC, 2022, p. 7). Relational eco-art creates spaces for meaningful dialogue to design opportunities for transcendence to ecological citizenship. Art also holds a potential revolutionary connection tool that can unite science and society in incidences of immersion and change to spur further creations and change. These works, which visually articulate diverse types of knowledge, are described in the literature as situated in the fecund middle, a hidden third zone in which components are rhizomatically connected. Here I use fecundity to refer to intellectual productivity. The study aimed to establish which characteristics in eco-art can contribute significantly more to sustainable eco-cultural development and what form and opportunities such transformative interventions manifest. The ways in which artists position their work to contribute to cultural climate change adaptation is interrogated in transdisciplinary praxis. In doing so, I interrogate previously published work of a select group of artists. This is not an inquiry into the methodology of transdisciplinary research, but, drawing on the artists’ praxis, I argue and expand on how the value of collaboration of scholars and artists working in these liminal spaces can reach new audiences. Two datasets are interrogated to analyse the approaches in art related to the environment, one eco-art characteristic derived from the author’s public art praxis, and the second, a broader interrogation of 50 international eco-artworks. By comparing and contrasting the two datasets, characteristics of intentionality, often built into the artworks, were identified. Six key characteristics were isolated, described and further interrogated to discover how they may create opportunities for society to build and foster potential cultural climate change solutions
Effects and consequences of natural and artificial light at night on small mammals in peri-urban Johannesburg, South Africa
(University of the Witwatersrand, Johannesburg, 2024) Oosthuizen, Tasha; Pillay, Neville; Oosthuizen, Marietjie
Studies investigating artificial light at night (ALAN) have increased over recent years. However, research examining the influence of ALAN on southern African small mammal species are lacking and even information on their basic biology is scarce. To close this knowledge gap, I investigated the effect of ALAN on different facets of animal behaviour in African small mammals. Firstly, I evaluated the impact of the natural (lunar cycle) and ALAN on the community composition and species abundance in two populations of small mammals. I chose two field sites: one facing Johannesburg (exposed to ALAN) and one facing away. I conducted mark-recapture trapping to ascertain the occurrence and abundance of small mammals. The Light site had both a higher species composition and a higher animal abundance when compared to the composition and abundance of the Dark site. The lunar cycle had an effect; on nights with a full moon, the species composition and animal abundance of both study sites declined, while on new moon nights, the opposite occurred, with an increase in both the species composition and abundance on the Light and Dark sites. The absence of a negative ALAN effect on the Light site can potentially be ascribed to the availability of microhabitats for small mammals to escape illumination, leaving them seemingly unaffected. Next, I assessed the locomotor activity of three species of commonly occurring rodents on the study area, one crepuscular (19 single-striped grass mice, Lemniscomys rosalia), one species with reportedly variable activity (19 angoni vlei rats, Otomys angoniensis) and one nocturnal (19 southern multimammate mice, Mastomys coucha). They were captured at a different location than the mark-recapture study sites and tested in captivity under natural (exposed to natural light and temperature changes), laboratory (standard laboratory conditions; 12h light:12h dark and constant temperature) and ALAN treatments. Lemniscomys rosalia exhibited crepuscular activity under all three experimental treatments, Otomys angoniensis was mostly nocturnal with some diurnal activity. The temporal activity profiles of the two species that showed some activity during the light hours were unaffected by ALAN. Mastomys coucha displayed strictly nocturnal activity during the natural and laboratory treatments, but during ALAN treatments the temporal activity profiles of some animals shifted so that they were active during the start of the day. Lemniscomys rosalia and O. angoniensis were more active under the natural treatment, whilst M. coucha was more active in the laboratory treatment. When exposed to 2 Lux ALAN presented remotely, there was no effect on the level of activity in O. angoniensis, L. rosalia showed a reduction of about 20% in its activity, whereas M. coucha reduced its activity by more than 50%. Finally, I studied how ALAN impacted the foraging behaviour of the three species under four treatments (during the day, at night, 2 Lux ALAN and 10 Lux ALAN). Foraging behaviour differed in the three species under different light conditions. Lemniscomys rosalia was risk-averse when feeding during the diurnal and nocturnal (no light at night) treatments. Otomys angoniensis showed irregular responses in their foraging behaviour under all foraging treatments. Mastomys coucha showed no differences when feeding under any of the nocturnal treatments, but it was inactive under the diurnal treatment. Overall, my study revealed that the effect of ALAN is not similar for all small mammalian species and appear to depend on both the spatial and temporal niches that the different species occupy. Strictly nocturnal animals seem to be affected the most, whereas animals that are active during the day showed lesser responses. Given the rapid increase in urbanisation and anthropogenic disturbances, more and more species are exposed to ALAN. Species that prefer darker, more secluded habitats appear to be more vulnerable and at higher risk of local extinctions as a result of disturbances, such as ALAN and habitat transformation. My study highlights that ALAN affects both nocturnal and diurnal rodents to the extent that it can have fitness consequences, including changed active times, foraging efficiency, movement patterns and susceptibility to predation. Finally, the disruption of rodent behaviour can have cascading effects for ecosystems and my study also emphasises the importance of safeguarding our night skies to protect biodiversity.
Employee Sentiments Concerning Workplace Greening
(University of the Witwatersrand, Johannesburg, 2023-09) Khorommbi, Phumudzo; Moolla, Raeesa
For centuries, people have continuously impacted the environment, resulting in an exponential rise in environmental problems and deterioration. In the quest to find solutions, business organisations have employed or tried to institute greening programmes, such as promoting waste at source and installing solar panels. However, it is essential for people, specifically in occupational settings, to see this as a need - for greening programmes to be effective. To this end, this study aimed to identify the elements that drive individuals to conduct environmentally responsible behaviours at work. This qualitative study collected data by administering surveys to research participants. Information related to eco-helping, eco-initiatives and eco-civic engagement was collected by administering surveys to local contractors at the PepsiCo site in Kempton Park, Johannesburg. The survey amassed 70 responses during October 2023. The study found that gender was an important indicator of pro-environmental behaviour, and that age affected a person’s inclination to act pro-environmentally. As this study relied on proclamations of good environmental intentions from participants, future studies should test this hypothesis in the field to quantify its success.
Environmental impact assessment performance in an african context: case studies from Southern Africa (South Africa, Namibia, Malawi, and Tanzania)
(University of the Witwatersrand, Johannesburg, 2024) Aljareo, Abdulhakim; Schwaibold, Ute; Watson, Ingrid
The Environmental Impact Assessment (EIA) system is a worldwide environmental policy tool, which has been introduced and adopted both in developed and developing countries. The EIA system is internationally acknowledged as an essential instrument to support sound decision-making in pursuit of sustainable development. Many countries have established the requirement for EIAs in their respective environmental legislative frameworks. However, considerable concerns are often raised about the inadequate performance of the EIA system in developing countries. The African developing countries have introduced EIA as an environmental policy implementation tool to their environmental policy and legal framework for environmental protection and management, as well as sustainable development promotion. However, the EIA system performance in the African developing country context is regarded as limited. The country context of the developing countries has been perceived to influence the performance of the EIA system. Fundamentally, the assessment of EIA system performance focuses on particular key EIA systemic components and EIA report, having limited consideration of the country context influence on the EIA system performance, and so does not provide a thorough understanding of the real causes of the limited EIA performance in the African context. Focusing on the EIA system performance in the African developing country context, an evaluation approach for EIA system performance and country context was developed. The developed approach was applied to four case studies from the southern African context (South Africa, Namibia, Malawi, and Tanzania). This was to evaluate EIA system components, EIA report, and country context. The research findings indicate that EIA system performance is limited due to the influence of the context of the case study countries. It was found that, despite the presence of the EIA legislative frameworks, EIA competent authorities, EIA procedural steps, and EIA reports in the case studies, different shortcomings have been identified such as misinterpretation of EIA provisions, limited EIA timeframes, incomprehensive EIA guidelines, insufficient provisions for conducting EIA follow-up and auditing. A further finding was the insufficient EIA report legal requirement which mirrored in the inadequate quality of the evaluated EIA reports. The most important v finding of this research is that EIA system performance depends on its country context. There is a clear relationship between country context of the case studies and EIA system development, implementation, and enforcement, thereby influencing EIA system performance. The key country context elements that were found to affect EIA system performance are the country legal, political, and socio-economic context, and the EIA stakeholders’ capacity. The consequences of the limited EIA stakeholders ‘capacity coupled with the inadequate country legal context due to insufficient laws to support justice in the administrative decisions, and access to information, had a significant impact on EIA system implementation and enforcement. The developmental state pressure on the EIA administration due to socio-economic challenges associated with political context issues such as interference and pressure also affected EIA system implementation and enforcement. The EIA system development was also influenced by the development state presented by the demand for economic development due to issues such as poverty and unemployment and the lack of political will and commitment to the EIA system. Based on this, a comprehensive understanding of the relationship between EIA system performance and the country context in Africa is required which can be achieved by using the developed evaluation approach in this study, to identify the possible measures for improving EIA system performance.
Evaluating the Effectiveness of Green Drop Audit Criterion in Relation to Its Link to Enforcement Protocol in South Africa
(University of the Witwatersrand, Johannesburg, 2022-08) Tshongweni, Olwethu Lenox; Tutu, Hlanganani; Richards, Heidi L.
The Green and Blue Drop programs are incentive-based regulatory systems based on the Department of Water and Sanitation's (DWS) realization that rewarding positive behaviour is more efficient and effective than penalizing undesirable behaviour. The Green Drop was developed for the Wastewater Quality Management Regulation certification program. In contrast, the Blue Drop was developed for the certification program for the Drinking Water Quality Management Regulation (Burgess, 2021). Most municipalities have accepted them and have raised awareness about the need for better efficiency in the wastewater sector. The Sand River, in Polokwane wastewater treatment works (WWTWs), was chosen as the research area for this study. This particular river was selected based on the premise of continuous non-compliance of the wastewater treatment plant and the resulting pressure it puts on the Sand River by compromising its quality, with the DWS not having a successful way of regulating and enforcing the water user to abide by the rules of the license that has been issued. This study aims to evaluate the effectiveness of the Green Drop Program audits and assessments about their link to the regulatory system within the DWS. Additionally, a risk assessment and cumulative risk rating are used to assess wastewater discharge into the Sand River in the Limpopo Province. Based on the observation made during the study, it appears that within the DWS organizational arrangements, the lack of coordination among the sectors (compliance monitoring, water quality management, the green drop program, and enforcement), lack of accountability, and the regulatory requirement of cooperation within DWS sectors have hindered implementation. Some of the non-compliance factors may be due to the misuse of funds meant for infrastructure development and difficulties relating to capacity, procurement, and management of the WWTWs. Moreover, DWS's absence of interactive data management systems and business processes contributes to non-compliance. The Polokwane WWTW, directly linked to the Sand River, is overloaded and needs to comply with the Water Use Licence (WUL) conditions. For example, the 21 August 2022, this facility was found to be non-compliant by 69.01%, collectively with administration and technical conditions of the WUL issued to the facility (DWS, 2022c). In addition, this investigation discovered that the Polokwane facility, which has been operating outside of regulations for the past four years, therefore, as calculated in equation 7 could be responsible for 72.3% of the hazards to people's health, the quality of the river's water, and the aquatic ecosystem life in the Sand River in a single month. As much as some municipalities do not perform according to the desired standards, there have been a few noticeable, well-performing ones reported in the green drop report released in 2022. These include Langebaan WWTW (90%), Riebeek Valley WWTW (97%), Gansevallei WWTW (84%), and Wellington WWTW (95%), and this illustrates that the Green Drop Certification is achievable if the municipalities follow and adhere to the Water Use Authorization (WUA) issued them (DWS, 2022b). The DWS must integrate the internal structures or link sectors responsible for monitoring and regulating municipal water service facilities and incentivize performing facilities to improve their performance. Additionally, facilities with minor compliance issues, such as water quality, must be referred to the Water Quality Management (WQM) unit for further investigation and recommendations. However, those non-compliances of authorized wastewater treatment facilities that require regulatory attention must be referred to the compliance monitoring sector through the system for compliance monitoring. Lastly, those facilities that are not authorized must be directed to enforcement for further action. Therefore, using the Integrated Regulatory Information System (IRIS) as the umbrella body for both database and work-based information has an imperative role that can curb some of the issues faced by the DWS. Standard operating procedures (SOPs) should guide all interactions between these systems.
Evaluation of the JSE’s environmental reporting requirements of South African listed companies
(University of the Witwatersrand, Johannesburg, 2024) Hariram, Viratha; Schwaibold, Ute
Through its mandatory environmental reporting requirements, the Johannesburg Stock Exchange (JSE) plays a pivotal role in the private sector to align to Environmental, Social and Governance frameworks and disclose information of a company’s environmental priorities and performance in addressing areas of concern. While there are attempts to safeguard the environment from damage and degradation, it is unclear if this framework is suitable at appropriately addressing the environmental areas of concern facing South Africa. In order to evaluate the JSE’s environmental requirements on listed companies, this study aimed to identify the local and global environmental priorities via the South African State of Environment Outlook Report (local view), National Development Plan (local view) and Sustainable Development Goals (global view) and thereafter determine if the Global Reporting Initiative, the only set of mandatory environmental requirements of the JSE, was adequately addressing the indicators they outlined. Furthermore, using a scoring system from zero to four, the study evaluated the alignment of ten randomly selected JSE listed companies against the requirements of the Global Reporting Initiative to note their level of adherence and alignment to the South African State of Environment Outlook Report, National Development Plan and Sustainable Development Goals. The results indicate that the Global Reporting Initiative (GRI) covers 73% of environmental priorities discussed in the South African State of Environment Outlook Report, National Development Plan and Sustainable Development Goals. Of the total 74 indicators of environmental concern identified from the three reports, the GRI did not require disclosure for 20 indicators. Only three indicators that were required to be disclosed by the GRI had scored a four on the rating scale due to it being an integrated disclosure that takes into account one or more other related environmental categories. The evaluation of the sampled listed company’s adherence to the GRI via their sustainability reports and integrated annual reports indicated that none of the companies had provided sufficient disclosures to meet the requirements of the GRI. 80% of the sampled listed companies made a strong alignment to the Sustainable Development Goals in their sustainability reports and / or integrated annual reports. A shortcoming of the JSE that was stated by all four sustainability experts interviewed was the lack of enforcement for listed companies to make quality and comprehensive disclosures or accountability expected from listed companies. There is no formal process of review or consequences for listed companies who do not comply.
Extreme weather events and human health in South Africa: implications for climate services
(University of the Witwatersrand, Johannesburg, 2022) Manyuchi, Albert Edgar; Erasmus, Barend; Wright, Caradee; Vogel, Coleen
Extreme weather events (EWEs), defined as ‘weather events that are rare at a particular place and time of the year’, have increasingly been affecting many countries worldwide (IPCC 2014). The increased occurrence and intensity of EWEs, among other factors, has increased public interest and demand for climate information. More detail is needed on EWEs and how they can be more effectively coupled to climate services in Africa. This study brings a compendium of empirical evidence, conceptual clarity and transdisciplinary approaches to policymakers, researchers and practitioners dealing with these crucial issues. The main aim of this study is to explore the human health effects of EWEs, particularly heat and the delivery of climate services for health in Africa. Through a systematic review, the study examines the potential impacts of heat on human health in Africa. Using a case study approach heathealth effects are evaluated including the status of climate services in the Agincourt subdistrict of South Africa. A novel systems theory-based conceptual framework and an inclusive analytical framework are employed to explore climate services delivery within the context of climate change adaptation. The study produces two main findings. First, EWEs particularly heat, potentially affects human health in Africa by changing mortality and morbidity patterns. In the Agincourt sub-district in particular, heat may be associated with adverse health effects on vulnerable populations, including inter alia the elderly, children and outdoor workers. Despite this, Africa-specific heat-health interventions and policy suggestions are scarce. Second, climate services are generally in embryonic stages of development and climate services for health in Agincourt subdistrict are non-existent. Within the South African context, the main barriers to delivery of climate services for health are paucity of interagency coordination and gaps in meteorological data. One of the key conclusions of the study is that African countries can promote development of climate services to adapt to EWEs such as heat. Heat, and heatwaves, for example, are already affecting populations, and are projected to increase in frequency and intensity with concomitant adverse effects on health outcomes on vulnerable population groups. The three key recommendations from this study are as follows. First, African policymakers and practitioners must avoid a reductionist approach to analysis of EWEs, especially heat impacts and start viewing these as harmful to human health. Therefore, governments must prioritise interventions, create institutions and formulate policy measures to deal with the health effects of heat within their national adaptations plans. Second, African countries must prioritise policy mixes that promote climate services in general and climate services for health in particular. And finally, further policy-science research that generates empirical evidence for African policymakers and practitioners engaged in international negotiations and programmes for climate change adaptation and climate services should be encouraged.
Factors affecting mammal utilisation of non-wildlife railway underpasses within the Greater Kruger, South Africa
(University of the Witwatersrand, Johannesburg, 2023) de Villiers, Hannah; Parrini, Francesca; Teren, Gabriella
Railways are an integral component of sustainable transport systems, but cause significant impacts to biodiversity, primarily through wildlife-train collisions and the habitat fragmentation created in the landscape. Crossing structures (CSs) for wildlife are the key mitigation measure for these adverse impacts, which will be critical throughout Africa, where 55,000 km of new railway lines are predicted to cut through hundreds of protected areas. For the first time in southern Africa, mammal usage of railway underpasses that were not designed to facilitate wildlife movement was studied using camera traps in the Greater Kruger National Park, South Africa. This study demonstrates that 70% of the terrestrial medium and large mammals species present in the area used at least one non-wildlife CS during the study period, with a total of 1,823 usage events by 33 species. Twelve medium to large African mammal species used underpasses regularly, improving the permeability of the railway line for these species. A viaduct design was characterised by almost four times the usage rate of a typical box culvert and was used by twice as many species, including megaherbivores and mesoherbivores, whereas box culverts supported a smaller number of species, of which the majority were predators. Species most affected by rail collisions in the study area were mostly herbivorous and seldom used non-wildlife underpasses. These results indicate that a railway line with only drainage culverts and the occasional viaduct is not effective in providing adequate safe crossing structures for megaherbivores and ungulate mesoherbivores. Contrary to expectations, vegetation and environmental factors influenced mammal usage of box culverts more than structural dimensions. Ensuring that there is high visibility through the structure, with less herbaceous cover and more woody cover outside of entrances, is likely to enhance culvert usage by most trophic groups. In a savanna context where faunal diversity is high and no single species is a target for mitigation, a range of underpass designs including larger viaducts, located in different types of vegetation cover, thereby combining the range of requirements of different guilds, is recommended.
Factors limiting karoo shrub populations in the Nama-Karoo
(University of the Witwatersrand, Johannesburg, 2023-09) Hebbelmann, Lisa; O’Connor, Tim; Witkowski, Ed
The Nama-Karoo Biome occupies the central and western region of South Africa. Nama-Karoo shrublands are dominated by karoo dwarf shrubs and in the wetter eastern regions annual and perennial grasses are interspersed among shrubs. Rainfall and grazing are the main drivers of vegetation change in the Nama-Karoo. Stocking rate, season of grazing and animal type are important influences on vegetation community composition, and rainfall determines shrub growth and the abundance of grass. More recently, fire has been identified as a driver of vegetation change. Understanding vegetation change is important for land managers in the Nama-Karoo as changes in karoo shrub communities have implications for forage availability. This thesis is focused on understanding how grazing, fire, grass-shrub competition, and soil moisture and temperature affect the composition, structure, growth and phenology of karoo shrubs in the Eastern Upper Karoo. Livestock type and stocking rate vary greatly over the greater Nama-Karoo area. Plant composition data from the Afrikaner-Hereford grazing trial at Grootfontein show that grazing has a strong legacy effect on Karoo rangelands and grazing-induced compositional and structural changes are clear many years after grazing has ceased. Different sheep breeds affect karoo shrub communities in different ways. There was a severe negative effect of heavy stocking with dorper sheep on karoo shrub communities and their structure; the impacts of merino sheep were significant but less severe. Effects of animal type and stocking rate were not consistent across the sites but appear to be dependent on edaphic factors. Soil physical properties appear to play an important part in determining the long term effects of grazing on karoo shrub communities. Fire is a novel disturbance in the Karoo. Nine sites which had experienced fire for the first time in history were studied for the effect of fire on the composition and structure of their shrub communities. The immediate effect of fire on karoo shrub communities was severe and the legacy effect of fire was significant. The nature of recovery after a fire depended on the abundance of fire-intolerant obligate reseeder shrubs that are killed by fire compared to the abundance of fire-tolerant resprouting shrubs. Rainfall and grazing management were important determinants of shrub recovery after a fire. As rainfall increases, grass biomass is predicted to increase, and this may result in fire becoming a more frequent occurrence in the Nama-Karoo. During periods of high rainfall, the biomass of grass in the Nama-Karoo increased at the expense of shrub cover. The effect of grass-shrub competition on shrub growth and phenology is not adequately explained by existing hypotheses of niche separation and succession. A field experiment which examined the growth and phenology of karoo shrubs in the presence of grass (unclipped control) and the absence of grass (grass removed by clipping) did not provide evidence of a competitive effect from grass on shrub growth or phenology. It did, however, provide valuable insight into how shrub growth and phenology are influenced by soil moisture and temperature. Rainfall in the Nama-Karoo is sporadic and a karoo shrub’s ability to utilise soil moisture will determine its ability to grow and successfully recruit. Shrub growth, with or without grasses in the vicinity, was strongly correlated with rainfall, but this was modified by temperature. Similarly, soil moisture and temperature were important for stem growth and phenology. Flowering occurred in response to soil moisture all year round but seeding occurred mainly during summer. Patterns of growth and phenology can be used by land managers to optimise shrub production while allowing phenological processes to take place. The findings of this study provide further insight into how grazing, fire, competition, soil moisture and temperature influence shrub populations and their structure, and these are discussed in the context of an existing state-and-transition model for the Eastern Upper Karoo. The importance of animal type and stocking rate, and how they vary across Nama-Karoo landscapes, is highlighted. The legacy of both grazing and fire reveal that the transitions between the alternate states of Nama-Karoo shrublands are not easily reversed in a management timeframe. It may take decades for a community changed by grazing or fire, acting independently or in conjunction, to return to their former state even under benign management. These findings along with a description of how soil moisture and temperature influence shrub growth and phenology have been used to make ecologically sound recommendations for the management of Nama-Karoo rangelands. Future research is needed to improve our understanding of how edaphic factors limit and influence karoo shrub populations across a variety of karoo landscapes, how repeat fires might change karoo vegetation, and whether temperature and the presence of pollinators influences shrub seed set. An assessment of the economic implications of vegetation change in the Nama-karoo is warranted so that management recommendations can be made with both ecology and economy in mind.
Functional feeding groups of mayfly nymphs (Ephemeroptera) in South African rivers of the North West and Limpopo Provinces
(University of the Witwatersrand, Johannesburg, 2024-02) Bossman, Esi H.; Harrison, James du G.; Woodford, Darragh J.
Researchers, primarily in the Northern hemisphere, have extensively studied mouthpart morphology and dietary variability in Ephemeroptera (colloquially called mayflies). Ephemeroptera are key primary consumers in rivers around the world and are used as aquatic biomonitoring indicators due to interspecific variation in ecological tolerances that make them good indicator taxa. Cummins (1973, 1974) created a functional feeding groups (FFG) classification system, based on northern hemisphere macroinvertebrates, as a universal tool to functionally categorise organisms based on their primary feeding mode within their habitat. The FFG classification system is useful in identifying interrelations between structural and functional components of an ecosystem. The aim of this study was to contribute knowledge on FFGs for particular mayfly species, in the southern African savanna biome, through mouthpart morphology and gut content analysis. Four study sites were sampled from the Magaliesberg (M) and Waterberg (W) catchments. There were three species studied, namely Afroptilum parvum (Family Baetidae), Afronurus barnardi (Family Heptageniidae) and Elassoneuria sp. (Family Oligoneuriidae). These species’ mouthparts were dissected and their macro- and microstructures were prepared for viewing with Scanning Electron Microscopy (SEM) and light microscopy. Micrographs and images showed variation in mouthpart morphology between all three species, with special attention to the labia and maxilla microstructures. The identification and description of microstructures that differentiate mayfly species (and the adaptations of these appendages to facilitate food uptake and ingestion) are important to address knowledge gaps regarding mayfly mouthpart morphology. A Principal Component Analysis (PCA) showed distinct grouping of the three species, with mandibles and maxillary palps showing the most variation between species. After analysis, the following feeding groups were assigned: Afroptilum parvum is a collector-gatherer feeder, Afronurus barnardi is a brusher-scraper feeder and Elassoneuria sp. is a filter feeder. This study showed, in part, that the Cummins’ (1973, 1974) classification categories were too broad for classifying organisms from a South African savanna stream. However, it is a good foundational starting point for region specific FFG classification systems. Thus, it is recommended to use the classification system Cummins created as a starting point for classifying organisms into FFGs with an initial definition that can be expanded upon to create individual classification systems for different localities.

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