4. Electronic Theses and Dissertations (ETDs) - Faculties submissions

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    Naturally occurring asbestos (NOA) and asbestos contamination of the environment: Implications for in-situ risk assessment and rehabilitation
    (University of the Witwatersrand, Johannesburg, 2023-01) Schapira, Jessica Shaye; Bolhar, Robert; Master, Sharad; Rumbold, Karl
    The risk associated with asbestos minerals is an enduring global concern, especially with regards to exposure at the sources. The risks connected to exposure in their natural contexts (i.e., derelict mine sites and naturally occurring asbestos) form the subject of this study. These sites are plentiful throughout Southern Africa (and Africa) and are considered as unconfined, thereby constituting large environmental and human health risks. Asbestos in these settings is not inherently hazardous unless dispersed from its sources into environmental systems, such as the atmosphere, where it may be inhaled. Compared to occupational asbestos exposure, environmental sources present unique challenges with respect to their potential risks. Literature focused on these sites is lacking and without extensive knowledge the risks remain greatly unknown, and thus asbestos site assessment frameworks are imperative. South Africa, with its geological richness, allows for all aspects of environmental asbestos to be studied in its natural context. In this research, mineral fibres from derelict asbestos mine sites were characterised mineralogically and geochemically to identify and assess their human health hazard potential, to define the degree of toxicity and to determine the potential negative environmental effects. High concentrations of heavy metals, including copper, iron, magnesium, manganese and zinc detrimental to human health and environmental functioning were measured in these fibrous minerals using X-ray fluorescence (XRF) . The chemical stability of four asbestos minerals was studied using batch isothermal dissolution tests in acidic solutions and their stability determined as follows: chrysotile < crocidolite < amosite < anthophyllite. Significant inferences can be made regarding the persistence of asbestos particles in their natural environments from dissolution kinetics mechanisms. The mineralogical, geochemical, and microbiological characterisation of solid asbestos mine waste rock substrates indicate that their properties, such as low macro and micronutrients and lack of properties of true soils, strongly alkaline pH and low to zero microbial abundance and diversity present significant challenges to rehabilitation strategies. Such parameters are identified as important baseline conditions that need to be considered prior to rehabilitation implementation, if long-term, self-sustaining ecological restoration is to be achieved on these sites. Present bio-solutions to ensure asbestos mine land rehabilitation success are discussed and the potential of using available agronomic bio-fertilisers (microbial strain Pseudomonas fluorescens) is examined. The growth-based assays indicate that this micro-organism is suitable for an environmental biotechnology applied to ecosystem restoration of asbestos-mining lands. Naturally Occurring Asbestos (NOA) occurrences are highly dependent upon the geological conditions, and understanding these in a large variety of settings may allow the development of predictive strategies necessary for in situ identification and hazard assessment required for health risk mitigation in the context of mining and other geologically disruptive activities. A variety of natural asbestos rock samples was examined, showing how geological databases relevant for predicting natural occurrences of asbestos provide baseline data required for mitigating asbestos exposure risks.
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    The impact of Covid-19 on international migration and remittances in developing countries
    (University of the Witwatersrand, Johannesburg, 2023-03-20) Zihindula, Awa; Eyita-Okon, Ekeminiabasi
    International migration from developing countries and remittances to those same countries have risen steadily over time due to various factors. Remittance is a source of income for most developing countries. Both sending and receiving countries benefit from migration. However, shocks such as natural crises, pandemics and epidemics (COVID-19 and Ebola) have devastated the economy worldwide, with a high unemployment rate and lower income. This research report aimed to study the impact of COVID-19 pandemic on migration and remittances in developing countries to establish the relationship between inflow remittances and migration outflow controlling for other factors (such as unemployment rate, internet access, economic growth and GDP growth). World Bank data and UNDESA data were used in the study. However, the developing countries were dichotomized as African and non_African countries for an in-depth analysis. The study employed multiple regression model to identify the associations between variables. Results of the study found that in African countries before and during COVID-19, there was no significant relationship between migration outflow and inflow of remittances. Furthermore, the control variables did not have an effect on the dependent variable. For non-African countries, the result shows that COVID-19 did significantly affect the relationship between inflow remittances and migration outflow; when migration outflow increases, there is a decrease in remittances inflow.
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    Double taxation agreements and their relevance for developing countries on the African continent
    (University of the Witwatersrand, Johannesburg, 2022) Klaas, Matthew
    Double Taxation Treaties have been developed and primarily used as a mechanism to remove double taxation between two independent states. With the onset of increased international or cross border trade it has become critical that governments engage in initiatives to avoid double taxation. African states have not been excluded from this phenomenon, as cross border trade and investment has been seen as a source of economic development for poor African states, and it is for this reason that the development or perhaps expansion of the tax treaty regime is a priority in Africa1. However, given the tax abuses that have beleaguered tax treaties and resulted in tax leakages, coupled with the fact that some tax treaties favour developed rather the developing states. The aim of this research report is to assess whether double taxation agreements are still relevant and whether these agreements provide any benefits for developing countries on the African continent. The research report will do this by reviewing the advantages and disadvantages of DTA’s, including the impact of DTA’s on Foreign Direct Investment and tax leakage on the African continent. The study will assess the different tax abuse’s that have beleaguered DTA’s. The research report will provide recommendations on how to deal with the current treaties in place and where there are no treaties what is the best course of action . The research methodology of this study will follow an analytical approach. This will be achieved by reviewing and analysing Secondary Data, such as Tax Treaties, research reports, textbooks, websites and opinions in articles to determine if double taxation agreements are still relevant and provide any benefits for developing countries on the African continent. The research report will conclude by providing recommendations on how to deal with the current treaties in place and where there are no treaties what is the best course of action. This will be based on the analyses and interpretation of the secondary data.
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    What are the challenges in taxing the informal economy and possible ways to overcome them?
    (University of the Witwatersrand, Johannesburg, 2021) Mbedu, Noluvuyo Bridgette
    Recent years have witnessed increased attention towards the challenges of taxing the informal economy (Joshi, Prichard & Heady 2012:1). However, this research report aimed to argue whether informal economy businesses in South Africa should be included in the tax system, given that the challenges of taxing the informal economy will need to be overcome. Other African countries such as Nigeria, Uganda, Cameroon and Ethiopia have attempted to tax the informal sector directly, and some businesses are bribing tax officers to reduce their company's tax payments. If the marginal bribe rate is lower than the statutory marginal tax rate, the company's tax payments will be reduced. (Kundt: 2017:6). Prichard (2012:16) has mentioned that the policy makers focus on the cost and benefits of taxing the informal economy. This research report also aimed to argue about the analysis that is needed to overcome the challenges of taxing the informal economy
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    The relationship between financial inclusion and economic development in developing countries
    (2020) Hlanti, Andile
    Financial inclusion in developing countries has not been explored to the same extent as for developed countries, and there is limited knowledge of what drives financial inclusion in developing countries. This paper looks at the relationship between financial inclusion and economic development in developing countries using an Index of Financial Inclusion (IFI) and three economic development parameters; GDP (PPP), GDP Per Capita and the Human Development Index (HDI). The study found a positive relationship between financial inclusion and economic development in developing countries. This paper analyses a combination of factors associated with the Index of Financial Inclusion by running 20 regression sets of transformed IFIs on two variable sets: aspects of the banking sector and socio-economic variables. The analysis also includes physical infrastructure factors in each regression, namely: transport infrastructure, mobile cellular subscriptions, internet connectivity and fixed telephone infrastructure. The study found that infrastructure requirements that are critical for enhancing financial inclusion in developing countries include: transport infrastructure, mobile cellular subscriptions and internet connectivity. The study further found that socioeconomic factors, such as access to credit, employment opportunities and adult literacy, are also important in ensuring financial inclusion. Certain banking variables hinder financial inclusion, like high-interest rates, while an increase in foreign assets is positively associated with financial inclusion in developing countries. This research ultimately contributes to the body of knowledge regarding financial inclusion in developing countries.