2149 research outputs found
Sort by
Climate temperature changes and excessive airflow rate effect on two key parameters: Dissolved oxygen and microbes in the biological treatment process-aerobic bioreactor.
No full textThe biological treatment process, aerobic bioreactor is essential for biodegradation of nutrients using microbes. The survival of microbes relies on the availability of nutrients and dissolved oxygen (DO). The challenge is that oxygen gas does not dissolve easily in wastewater which motivates plant operators to apply excessive airflow rates to uphold oxygen in the aerobic bioreactor. In addition, the rising climate temperatures suppress DO, which threatens the survival of microbes, risking poor effluent discharge. Hence, the study analyzed the climate temperature changes and excessive airflow rate effect on microbes and DO simultaneously. Climate temperature changes and excessive airflow rate on microbes and DO were analyzed using linear regression, ANOVA, and coefficient of determination (R²). Findings disclosed that climate temperature changes produced R² (0.86) and negative linear regression (0.1076 mg/L) on DO while producing R² (0.59) and positive linear regression (0.168 mg/L) on microbes. Further findings disclosed that excessive airflow rates produced R² (0.84) and positive linear
regression (0.0057 mg/L) on DO while producing R² (0.0003) and positive linear regression (0.001 mg/L) on microbes. Overall climate temperatures showed variations on microbes' growth (P - 8.7424 × 109 0.05) and DO (P - 0.98512 > 0.05). This suggests that climate temperature change will benefit microbes despite DO being suppressed while excessive airflow rates will not benefit microbes but enhance global warming due to emissions released by blowers/pumps
A critical examination of the socio-onomastic controversy of Sepedi and Sesotho sa Leboa/ Northern Sotho language names and the role and effectiveness of the Commission for Cultural, Religious and Linguistic Communities.
No full textThe article examines the failure to take action and implement effective measures in resolving the socio-onomastic controversy surrounding the Sepedi and Northern Sotho/Sesotho sa Leboa language names, while evaluating the effectiveness of the Commission for the Promotion and Protection of the Rights of Cultural, Religious and Linguistic Communities (CRL Commission) as a Chapter 9 institution in the matter. The research was conducted at five South African universities where the language is offered as a module. Employing a qualitative approach, the study primarily uses content analysis of data from constitutional documents and minutes from the Parliamentary Joint Constitution Review Committee. In addition, self-administered questionnaires and face-to-face interviews were employed to supplement the content analysis as qualitative. A purposeful sampling technique was used to select 267 participants, including students, lecturers, language authorities and experts from the Department of Sport, Arts and Culture, as well as its provincial departments in Limpopo and Gauteng provinces. The article establishes that the lack of intervention by the CRL Commission exacerbates non-compliance issues as far as dual use of these names is concerned. It further argues that the lack of compliance not only undermines linguistic rights, but also disregards South Africa’s constitutional democracy, which should be safeguarded. Practical and decisive measures, rooted in constitutional principles, are recommended to resolve the matter effectively
Yield and quality response of indeterminate tomatoes to combined growing methods and rootstock cultivars.
No full textLimited comparative research exists on evaluating the performance of tomato rootstocks under different growing methods, resulting in growers facing challenges when deciding which rootstock and growing method to use for improved yield. The effect of growing methods (scion of a single stem or double stems and non-grafted plant as the control) and rootstock cultivars (Goldbac, SVTX6258, and Booster) on the yield and quality of tomatoes grown in a plastic tunnel and a shade net structure was investigated. The splice grafting method was followed. In a plastic tunnel experiment, grafting and rootstock cultivar did not significantly affect the total soluble solids (TSS), pH, and electrical conductivity (EC) of the tomato juice, as well as percentage weight loss, yield, and fruit firmness. However, the Booster rootstock with a scion of 2 stems had high fruit Mg, K, P, and Fe contents, while the Goldbac rootstock with a scion of 1 stem and 2 stems had high fruit Ca and Fe contents compared to other treatments. The Goldbac and Booster rootstocks grafted to a scion of 2 stems had a high marketable yield. In a shade net experiment, the Booster rootstock with a scion of 2 stems had a high early harvest and total yield of tomatoes, followed by the Goldbac rootstock with a scion of 2 stems. Higher incidences of fruit cracking were noticed on the Booster rootstock grafted with a scion of a single stem. Generally, grafted plants on Booster and Goldbac had improved Mg, K, and P contents, unlike SVTX6258 with a scion of 1 stem. The Booster rootstock with a scion of 2 stems had significantly higher Mg, K, and P contents, while the sodium (Na) fruit content was high on the SVTX6258 rootstock with a scion of 1 stem. Grafting did not significantly affect fruit physiological disorders, weight loss, and TSS, or pH and EC of tomato juice. Grafting with a scion of two stems at the seedling stage significantly improved the tomato fruit mineral content and the total and marketable yield in a plastic tunnel and a shade net structure
Impact of combined rootstock cultivar and grafting method on growth, yield, and quality of soilless-grown cucumber (Cucumis sativus L.) in a non-temperature-controlled high tunnel.
No full textGrowers rarely use the grafting method on a double-root system due to limited information on the added advantages for increased plant vigour and yield of soilless-grown cucumber (Cucumis sativus L.). The study aimed to investigate the effect of combining rootstock cultivar and the grafting method on the growth, yield, and quality of soilless-grown cucumber in a non-temperature-controlled (NTC) tunnel. Two rootstock cultivars, Flexifort (Flex) (Cucurbita maxima × Cucurbita moschata) and Ferro (Fer) (C. maxima × C. moschata), were grafted with scion cultivar Hoplita (H) to either single- (1R) or double- (2R) root systems, and the original scion root system was combined with either a Flexifort or Ferro
rootstock (O1R) to two root systems and a non-grafted plant (Hoplita). Plants were grown in 10 L containers filled with sawdust as a growing medium. The leaf number was higher in ‘HO1RFlex’ combinations, while the non-grafted plants had a significantly lower leaf number. Thicker stem diameter was obtained from non-grafted plants. The tallest plants were obtained from HO1Fer combinations at 39, 53, and 101 days after transplanting (DAT), while non-grafted plants at 25 and 101 DAT were the shortest plants. Plants grafted to single or double-root systems, regardless of rootstock cultivar, had higher early, marketable, and total yield compared to non-grafted cucumber. Many medium-sized fruits were obtained in ‘HO1RFlex’ combinations during the early harvest. The total soluble solids (TSSs) of cucumber juice were higher in ‘H1RFer’ while fruit mineral content was not affected by the combined rootstock cultivar and grafting method. Grafting to a double-root system using the original scion roots combined with rootstock or double rootstock had a limited effect compared to plants grafted to a single-root system. It is recommended that scion be grafted to a single-root system of either rootstock Ferro or Flexifort compared to a double-root system, particularly for the cost effectiveness of seeds and labour used in grafting, as well as for improved vegetative growth, including early marketable and total yield of cucumber.
The growing containers of various sizes need further investigation to allow for the root extension and growth of grafted plants
Analysis, occurrence and removal of polychlorinated biphenyls (PCBs) in mine water – A review.
No full textBackground Polychlorinated biphenyls (PCBs) are persistent organic pollutants, and assuch, they are subject to prohibition under the Stockholm Convention, due to their environmental and health effects. Despite their historical utilisation in mining operations, the presence of PCBs in mining influenced water (MIW) remains a subject that has not been adequately investigated. PCBs sorbed to suspended solids are often overlooked in conventional water analyses, contributing to misconceptions about their presence in the environment. Given their bioaccumulative and endocrine-disrupting properties, even minute amounts of PCBs in MIW pose substantial risks to ecosystems and human health.
Main body This review article describes the occurrence, environmental fate and treatment of PCBs in MIW and addresses critical knowledge gaps in the mining industry. Historical data demonstrate that PCBs were extensively utilised in mining applications, including dielectric fluids and hydraulic systems. Despite decades of regulatory oversight, residual PCBs persist in MIW, often at concentrations below DIN or ISO detection limits, yet they accumulate through the food web. The sampling challenges posed by the low solubility and sorption of PCBs to solids necessitate the employment of advanced analytical techniques. This study summarises the results of literature searches, laboratory analyses and discussions with international experts. There is still a global lack of monitoring and awareness of PCB contamination in MIW, with Germany being a notable exception. The study’s primary sections address PCB detection methods, sampling techniques and environmental behaviour, emphasising the persistence and mobility of PCBs through adsorption and desorption processes. Treatment strategies encompass biodegradation, filtration, and thermal processes; however, the efficacy of these strategies is contingent on the specific characteristics of the site.
Conclusions PCBs in MIW pose a substantial environmental challenge and necessitate multidisciplinary efforts to monitor, understand and eliminate their adverse effects. This review is a comprehensive resource for researchers, regulators and industry representatives, facilitating science-based decisions to protect ecosystems and comply with international environmental standards. Continued research is essential to refine detection methods and develop innovative remediation technologies for PCBs
A Recycling Nexus: The Design of a Plastic Upcycling Facility in Pretoria
No full textSubmitted in partial fulfilment of the requirements for the degree, Master of Architecture (MArch) in the Department of Architecture and Industrial Design within the Faculty of Engineering and the Built Environment at the Tshwane University Of Technology.Plastic waste poses a significant threat to both human health and the natural environment. In Pretoria, the Municipal Solid Waste Management System (MSWMS) is struggling to keep up with the city’s rapid urbanisation, while informal communities have resorted to collecting recyclables to sell and sustain their livelihoods. Although waste pickers are recognised in various policies, they are yet to be formally integrated into the MSWMS. The activities of waste pickers often lead to problematic environmental conditions, including illegal dumping, sorting and burning of plastic waste. This dissertation explores the informal economy and its economic contributions in order to identify approaches for integrating and empowering waste pickers. An architectural intervention was proposed in the form of a plastic upcycling facility that will integrate waste pickers and recognise the critical role they play in recycling, without the municipality adapting the existing waste management system (WMS). The architectural response entails moving from the “ugliness” of plastic waste to the “beauty” of architecture through upcycled plastic elements captured in the final architectural product. A centralised plastic upcycling facility would increase plastic waste collection rates and improve social equity and environmental sustainability, as it would be within reach of more informal settlements and economic areas. A systematic approach was adopted to analyse and examine the different aspects of the project while using pragmatic thinking and an iterative design approach to develop the architectural intervention through trial and error. This resulted in a facility dedicated to empowering waste pickers, recycling and upcycling plastic waste. It will streamline plastic waste collection and promote social equity through the integration of waste pickers to provide formal employment opportunities
TUT Connect- Golaganya-Chumanisa-Kgokanya
No full textHeita!, TUT’s electronic student newsletter, scooped a Silver Award of Excellence at the Marketing, Advancement and Communication in Education (MACE) Excellence Awards, held at the Indaba Hotel in Fourways, Johannesburg, on 13 November. The MACE Excellence Awards celebrate outstanding achievement by
specialists and practitioners in marketing, advancement and communication within the higher-education sector, recognising excellence on an annual basis
Understanding PFAS behavior: Analysing contamination patterns in surface water and sediment of the Apies river, South Africa.
No full textPer- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants widely detected in water and sediment worldwide. Despite growing concerns about their ecological and health risks, their distribution in African aquatic
environments remains understudied. This study addresses the knowledge gap in PFAS contamination by analysing the spatial and temporal distribution of 18 PFAS in Apies River water and sediment in Pretoria, South Africa. Surface water
and sediment samples were collected upstream and downstream of the Apies River during dry seasons. The analysis of PFAS concentrations was conducted using liquid chromatography-tandem mass spectrometry. Statistical analysis, including paired t-tests, non-metric multidimensional scaling, and hierarchical cluster analysis, were applied to determine spatial and temporal trends. The study revealed significant spatial variations in PFAS contamination, with upstream locations consistently exhibiting higher concentrations than downstream. In surface water samples, L_PFBS, 4:2 FTS, 6:2 FTS, and L_PFHpS showed statistically significant differences (p<0.05) between sites. Perfluorocarboxylic acids were the dominant PFAS class in surface water (50.47–57.15%), whereas perfluorosulfonic acids were more prevalent in sediments. Upstream sediment had higher L_PFHpS (43.00 ng/g), L_PFDS (38.89 ng/g), and L_PFHxS (23.91 ng/g) than downstream (31.96, 27.84, and 18.02 ng/g, respectively). The findings reveal contamination sources and partitioning between surface water and sediments, aiding in water quality management and pollution mitigation strategies
Shifting sands of the past and the present in drama of the new south africa: Neil Coppen’s Tin Bucket Drum and nadia davids’ What Remains.
No full textThe experimental pedigree of South African drama of the anti-apartheid period requires no introduction. This pedigree was established during the years of antiapartheid playwriting of the 1970s and 80s when South Africa’s iniquitous politics of race relations was put under the spotlight on local and world stages. This was achieved through the work of playwrights such as mbongeni Ngema, Percy mtwa, Athol Fugard and matsemela Manaka, among others. This paper focuses on the drama of the post-apartheid era to argue that three decades after the formal end of apartheid, some of the most recent plays from South Africa have adopted themes and styles that draw from an atavistic recourse to the stylistics and experimental drama of apartheid era protest plays to address new challenges which are steeped in continuing social injustice. The paper adopts the climatic metaphor of shifting sands to analyse how post-apartheid drama simultaneously crosses and integrates aesthetic borders to create innovative and complex narratives which bring together the craft of African storytelling theatre, dance and choreography that are in turn infused with multi-media as social commentary. The paper focuses on Neil coppen’s Tin Bucket Drum and Nadia Davids’ What Remains as examples of the continuing provenance of experimental aesthetic border crossing in the
drama of South Africa today. This aesthetic border crossing deploys new forms of multimedia as decentring social critique in post-apartheid South Africa. The paper showcases how Nadia Davids and Neil coppen use the past and the present both literally and metaphorically to craft intriguing contemporary dramas in which incident and character come together as profound metaphors of the country’s ongoing struggles to reconcile a troubled past and imagined future
Climate governance in the BRICS: Pathways toward net‑zero emissions.
No full textClimate governance is essential for tackling global climate challenges and advancing toward net-zero objectives. This study focuses on the BRICS nations—Brazil, Russia, India, China, and South Africa—examining their strategies, policies, and challenges in tackling climate change. It explores similarities and distinctions in climate governance across BRICS countries, offering recommendations for enhancing responsible climate governance. The study uses an integrated comparative
trend analysis of literature to examine and contrast strategies and analyse policies and challenges across BRICS nations. This study finds that the BRICS economies’ persistent dependence on coal and other fossil fuels remains a major barrier to the transition toward net-zero emissions, underscoring the structural complexities of aligning economic growth with sustainability goals. Findings highlight the importance of collective action, policy coherence, and regional leadership in promoting effective climate governance within BRICS. It further emphasizes the need for Environmental, Social and Governance (ESG)-aligned practices and proactive engagement to address the complexities of climate change. The paper recommends increased investment in climate finance while promoting regional and international cooperation to support transition to a low carbon economy. It contributes valuable insights into the responsibilities of BRICS nations in influencing the trajectory of global climate governance