Economic evaluation of chemical and biological control methods on four aquatic weeds in South Africa
- Authors: Maluleke, Mary
- Date: 2020
- Subjects: Invasive plants -- Biological control -- Economic aspects -- South Africa , Introduced organisms -- Biological control -- Economic aspects -- South Africa , Aquatic weeds -- Biological control -- Economic aspects -- South Africa , Aquatic weeds -- Control -- Economic aspects -- South Africa , Aquatic resources -- Management , Cost effectiveness , Net present value , Herbicides -- Cost effectiveness , Working for Water Programme , Water conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/145953 , vital:38481
- Description: Invasive alien plants (IAPs) of various kinds pose a threat to ecosystems, biodiversity, conservation and overall economy. In a world experiencing exponential increase in IAPs – this issue has become endemic, especially for developing countries such as South Africa. South Africa is a water scarce country and IAPs increase water stress. Thus, South Africa must invest in a more realistic, environmentally and economically inclusive policy outlook on the management of IAPs including aquatic weeds. This is especially urgent when considering the changing global climate, which is predicted to further reduce the quantity and quality of potable water. The Working for Water Programme (WfW) in South Africa aimed at addressing the issue of IAPs in a way that protects the environment as well as produces maximum return to society through poverty alleviation. As such, the aquatic weeds management strategy put in place for four of South Africa’s aquatic weeds Pista stratiotes, Salvinia molesta, Azolla filiculoides and Myriophyllum aquaticum - should be one that is cost-effective, efficient and sustainable; yielding the best possible return on investment. Since these four weeds are already under complete biological control, in the absence of biological agents, the WfW programme would have used herbicides to control these weeds. As such, this thesis conducted a retrospective analysis of the relative herbicide cost-saving associated with the use of biological control. To do this, due to existing limitations, E. crassipes was used as a surrogate weed and its herbicide control costs were used as proxy for the herbicide control cost estimates of the four selected weeds; with reasonable conversion factors applied to cater for the biological difference of the five weeds. Using the cost benefit analysis (CBA) framework, the net present cost (NPC) of each control method was calculated to which the relative cost-saving was considered to represent the avoided cost of using biological control instead of chemical control on these weeds. The avoided cost was used as the main benefit component when deriving the relative benefit cost ratios (BCR). Two scenarios were used, one assuming no follow-up requirement and the other assuming one follow-up requirement for chemical control. Using an 8% discount rate, the study found that the estimated cost of the biological control method on all four aquatic weeds was about R7,843,205 while for chemical control the estimated costs would have costed R149,580,142, R268,264,838 and R881,711,738 for application by means of a boat, bakkie and knapsack. Chemical control cost estimates would have increased to about R164,538,052, R295,216,120 and R1,008,761,000 for boat, bakkie and knapsack approach respectively when including a possible follow-up programme. These would have led to positive BCRs of 90.24:1, 164.97:1 and 557.99:1 across the three chemical control approaches without a follow-up (with BCR of about 99.67:1, 182.00:1 and 631.56:1 for the boat, bakkie and knapsack approach respectively with the accepted follow-up programme). When running a sensitivity test with varying discount rates of 5% and 10%, these results remained robust. As such, failing to reject the dominant hypothesis in literature, the main conclusion of the study is that biological control is indeed the more cost-effective management option compared to chemical control with respect to herbicide cost-saving. Further, biological control is most-likely to produce more environmental cost-saving and water-saving over chemical control. The study recommends the continued use of the biological control investment on the four aquatic weeds under study as well as on emerging aquatic weeds such as Iris pseudacorus, Nymphaea mexicana and Sagittaria platyphylla in South Africa.
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- Date Issued: 2020
The Impact of Energy Consumption on The Profitability and Renewable Energy Preference among SMEs in The KSD Municipality
- Authors: Vikela, Sithole Liso
- Date: 2019-03
- Subjects: Energy consumption , Cost effectiveness
- Language: English
- Type: Master's/Doctoral theses , text
- Identifier: http://hdl.handle.net/11260/6730 , vital:47570
- Description: This study investigated the impact of energy consumption on the profitability and renewable energy preference among SMEs in the King Sabata Dalindyebo (KSD) local municipality. Cross sectional data was collected using a questionnaire and the adoption of information acceleration (IA) technique. The theoretical framework applied in this study is the theory of consumer-fuel-energy choice which is based on the energy ladder model and the associated fuel switching. Short-run sensitivity analysis (SRA), cost-benefit analysis (CBA) and multinomial logit model (MNL) were employed to measure the profitability and switching behaviour of the firms. SRA showed that the average monthly profit/loss by all firm categories were positive indicating a profit in the consumption of non-renewable energy (NRE). In contrast, results showed that all categories of the firms’ ran at loss if they were to switch to the renewable energy (RE) immediately. Results for CBA indicate that only RE system option satisfied the economic viability of all the three CBA decision criteria on both discount rates, proving to be a viable investment choice for all firm categories. The MNL regression results showed that the number of rooms, firm revenue, irregular power experiences, product information, price, business age, firm grades, gender of the respondent, and the educational levels have a statistically significant impact on willingness to switching from substantial to full willingness. The study recommends establishment of financial subsidy to SMEs to enable them switch to RE system. The research also suggests the need for policies and incentives on profit enhancing strategies, symmetric product information and environmental benefits for switching to RE by SMEs in the rural areas. Key words: Energy consumption, Profitability, Willin¬gness to switch, Cost-Benefit analysis, Multinomial logit model. , Thesis (MCom) -- Faculty of Commerce and Administration, 2019
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- Date Issued: 2019-03
Dynamic adaptive cost model for wireless Internet connectivity in African rural communities
- Authors: Sibanda, Khulumani
- Date: 2010
- Subjects: Internet , Community development -- South Africa -- Eastern Cape , Cost effectiveness , Wireless communication systems , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Computer Science)
- Identifier: vital:11389 , http://hdl.handle.net/10353/380 , Internet , Community development -- South Africa -- Eastern Cape , Cost effectiveness , Wireless communication systems , Rural development -- South Africa -- Eastern Cape
- Description: In today’s dynamic technological landscape, wireless communication networks have become an important part of economic development. The emergence of wireless technologies raises hopes to extend communication to remote areas that have not seen any tangible deployment to date. As developing nations pin their hopes to wireless technologies, cost models for wireless communication networks are becoming vital to support the emerging technologies. However, varying cost changes raise critical challenges to the estimation of both capital expenditure and operational expenditure. The network deployment process has numerous events that may cause adjustments to initially estimated project costs. These adjustments are necessary for a cost management plan and this plan includes monitoring cost performance and ensuring that only appropriate changes are made to the network project. The incidents that may cause cost changes can not be entirely predicted as their distribution tend to change dynamically from time to time. Estimating network deployment costs in such a dynamic environment necessitates cost models that can adapt to random occurrence of cost changes. Widely used cost models are usually performed by experienced personnel whose engineering experience is derived from deploying similar networks. In this approach experienced personnel add a certain percentage to the cost estimate to cater for contingency costs. Certainly such an approach depends on individual opinion, making it subjective and void of mathematical estimating relationships which are of paramount importance in ensuring that estimated deployment costs are sufficient to deal with cost uncertainties. We observe that existing approaches can only explore a limited solution space and hence can lead to cost overruns if implemented in dynamically cost changing environments. This thesis presents a wireless communication network deployment cost model that incorporates uncertainties into the final cost estimate. The model is adaptive to unpredictable cost changes since it allows adjustments of confidence levels when calculating contingency costs. This allows dynamically updating the cost changes without the cost model being reconstructed from scratch. We make use of the Poisson process in modeling the occurrence of incidents that are responsible for causing cost changes during network deployment. We also show that the occurrence of the incidents causing cost change are random and tend to follow the Poisson distribution. Using different levels of confidence we model various cost contingencies and make sensitivity analyses to identify the probability of cost overrun when given different contingencies. The dynamic adaptive cost model can be used either at the strategic level to understand the cost of a particular technique or at the operational level, as a way to show how Poisson process in network deployment can compare with engineering experience and other estimating techniques. We believe that the model is useful for remote areas where deployment costs are volatile and the distribution of incidents causing cost change to original cost estimates are diverse and dynamically changing. Further we expect that our research improves the knowledge base of information about the costs for rural communities to connect to the Internet, consequently providing useful input to future policy debates. This work is further poised to be a utility function to help those planning internet infrastructure deployments in least developed regions.
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- Date Issued: 2010
A cost-benefit analysis of electricity supply in a developing country, with reference to Venda
- Authors: Themeli, Tshimangadzo Booi
- Date: 1992
- Subjects: Electrification -- Economic aspects -- South Africa -- Venda , Electric utilities -- South Africa -- Venda , Cost effectiveness , Electrification -- Cost effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1022 , http://hdl.handle.net/10962/d1002757 , Electrification -- Economic aspects -- South Africa -- Venda , Electric utilities -- South Africa -- Venda , Cost effectiveness , Electrification -- Cost effectiveness
- Description: This study concentrates specificaUy on assessing those elements of private and external costs and benefits which need to be accounted for in analyzing the role of electricity supply in a developing region. To facilitate this aim, three interrelated questions are addressed. The first question examines the reasons why a critical need for electrification in developing areas exists. In this regard, a selective review of the literature on development economics is offered, illuminating the previous neglect of the rural dimension in development and the associated problems of poverty and inequality, a lack of infrastructure and the general inability to fulfill basic needs. The second question is devoted exclusively to an economic analysis of the supply of electricity in developing areas. A broad theoretical review on whether an unregulated or regulated (private or public) sector should be responsible for the provision of electrification is presented. This evaluation highlights the various welfare implications and efficiency considerations that appear to be relevant in the present context. The final question, which constitutes the central proposition of the thesis, establishes how electrification should be supplied in developing areas. To this end, the conditions specific to a region in Venda are discussed. An attempt is made to identify the private and external costs and benefits relating to electricity supply and the corresponding costs and benefits pertaining to alternative sources of energy. Since the incidence and nature of these costs and benefits could only be ascertained from individual households, it was deemed necessary to undertake a questionnaire study of residents in Makwarela township and its periurban settlement of Lufule-Tshisele. A number of basic trends were evident from the research results. As far as the various benefits are concerned, respondents tended to place a much higher value on both the private and external benefits associated with electricity than its alternatives. At the same time, the survey found that although the private (or monetary) cost of electricity far exceeded the corresponding cost of alternative energy sources, the external costs were significant in the case of alternative energy sources, but virtually non-existent in the case of electricity. On the whole, the Venda survey seems to suggest that an economic case can be made for involving the broader community in subsidising the supply of electricity in Makwarela, Lufule-Tshisele and other areas. While such a subsidy can perhaps be justified on distribution grounds alone, and more specifically in terms of the rapid and pronounced effect it is likely to have on the quality of life in the region, its real worth lies in the fact that it may confer certain external benefits on the community.
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- Date Issued: 1992
Some theoretical considerations in applying cost-benefit analysis to Black education in South Africa
- Authors: Hosking, Stephen Gerald
- Date: 1983
- Subjects: Cost effectiveness , Black people -- Education -- South Africa -- Economic aspects , Education -- Economic aspects -- South Africa , Education -- Finance -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1047 , http://hdl.handle.net/10962/d1006150 , Cost effectiveness , Black people -- Education -- South Africa -- Economic aspects , Education -- Economic aspects -- South Africa , Education -- Finance -- South Africa
- Description: From introduction: In this thesis some of the economic theory underlying the application of cost-benefit analysis to education is considered with the view to discussing its relevance to the field of educational provision for Black people in South Africa. The fact that educational facilities available to Blacks are so vastly inferior to those of the Whites has given rise to virtual consensus that more has to be provided for the Black population. The economic implications of education are frequently cited to support this viewpoint. Using (a ) the theoretical bases established in chapters 1 and 2, (b) the review of the rate of return to education studies in chapter 3 and (c) the broader socio-economic considerations introduced in chapter 4, it is concluded that this viewpoint is not necessarily well founded in South Africa and that the potential for greater use of the techniques described, is far from exhausted.
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- Date Issued: 1983