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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

An investigation of the treatment efficacy of permeable pavements for water quality performance in South Africa

Schieritz, René January 2016 (has links)
Stormwater pollution has been recognised as a leading cause of ecological degradation of urban streams. Sustainable Drainage Systems (SuDS) attempt to address stormwater impacts by flow attenuation and pollutant treatment, simultaneously providing amenities such as water for use in irrigation or other suitable uses. Permeable pavements are a form of SuDS that provide on-source treatment and storage of stormwater while retaining the functionality of hardened surfaces. They have been studied extensively in the international literature but no studies in a South African context have been published. This study investigated the water quality performance of a recently constructed permeable pavement at the University of Cape Town. Effluent quality was assessed against the South African Water Quality Guidelines and an ecosystem assessment tool. The results showed that, while the pavement had been constructed with unwashed aggregate and therefore exported suspended solids, effluent still met the standards required for irrigation and some industrial uses. However, the effluent did not meet desirable nutrient standards for discharge into the aquatic ecosystem. The performance of the pavement was similar to values reported in the international literature, suggesting that the quality ranges can be extrapolated to other permeable pavements. The newly constructed pavement displayed noteworthy inter-event progression, as well as identifiable intra-event variation of pollutant concentrations. Further research into effluent toxicity, long-term impacts of unwashed aggregate and catchment-wide impacts of permeable pavements are recommended.
452

Exploring the ecological and social benefits of the Khayelitsha Wetlands Park

Mathenjwa, Fezile January 2017 (has links)
In a world confronted by rapid urbanization linked with dramatic population growth rates, there is a general consensus that quality urban green spaces are important components of urban landscapes. Urban green spaces are defined as open spaces in urban areas primarily covered with vegetation, which are available to users within the community. They have the ability to shape the image of cities and provide various important socioecological benefits, which can contribute to improving the quality of life within these urban communities. In Cape Town, the provision of readily accessible quality urban green spaces is often overridden by other conflicting demands, such as biodiversity conservation and infrastructure development demands. The literature suggests that Cape Town has ample available green spaces. However, the accessibility of this green space is linked to issues of poor management and maintenance, and as a result poor urban spaces are often associated with criminal activities, and are therefore unavailable to benefit urban communities. This is particularly evident in areas which have a low socioeconomic status. This study explores the ecosystem services offered by the Khayelitsha Wetlands Park in the Khayelitsha Township on the Cape Flats. A variety of methods were used to establish the condition of the Wetlands Park and assess the impacts of various uses (e.g. recreation, agriculture etc.) on the vegetation structure and water quality. Qualitative semi-structured interviews were also conducted to assess the local community's uses and perceptions of this green space. A Complex Adaptive Landscape (CAL) approach was adopted to derive the positive and negative social-ecological impacts of the Khayelitsha Wetlands Park. The vegetation structure assessment results showed a dominance of emergent and invasive vegetation, such as Typha capensis and Acacia cyclops, and indicates a high level of degradation and a lack of indigenous vegetation species. The water quality analysis reveals high concentrations of physiochemical and microbial pollutants, where a majority exceeded the Targeted Water Quality Ranges (TWQR) recommended by the Department of Water Affairs for livestock watering, irrigation and human use. Findings from the semi-structured interviews, revealed that a majority of users v visit the Park for multiple activities offered by the Park. These include relaxation, creating and maintaining social relations, sports and recreation and agricultural use. The CAL framework revealed negative and positive feedback mechanisms at play in this urban green space. The negative feedback effects are illustrated and confirmed by poor water quality and a predominantly alien infested vegetation structure. The poor ecological condition of the Wetland is linked to a number of anthropogenic influences, including the discharge of treated waste and untreated waste from both agricultural and urban waste sources, indicating the complexity of managing the Khayelitsha Wetlands Park. Since a number of users and management institutions are connected to the Khayelitsha Wetlands Park, their involvement in the management thereof is crucial for effectively solving the issues identified.
453

The role of open streets Cape Town street events in shaping everyday mobility in Salt River and Observatory : towards bridging mobile, spatial and social divide

Taylor, Frances Jessica January 2015 (has links)
This study interrogates the role of Open Streets Cape Town's day-long street events in disrupting complex systems and hierarchies of everyday street mobility that maintain the mobile, spatial and social divides of Cape Town. The test was whether OSCT events 1) bridged the mobile divide by replacing car-dominated streets with people-centred public space; 2) bridged the spatial divide by bringing fluidity to the mobility of people between usually isolated public spaces; and 3) bridged the social divide by replacing practices of avoidance and exclusion with an everyday cosmopolitan sensibility. The investigation used mobile methodologies and an embedded approach. OSCT proved to be successful at bridging the mobile divide by creating a shared public space, but had mixed success with bridging spatial and social divides. A greater sensitivity to how existing social and spatial divides can be reproduced during events would improve this. Sager's (2006) freedom of mobility framework was reworked and proved to be useful in monitoring individuals situated differently in the shifting complex of power, identity and everyday life across a changing motilities landscape. The underlying mobility framework revealed a need for developing better street navigation skills to create robust and equitable freedom of mobility for street users, necessary for independence from mediators such as cars, private street security and prejudice ideas about people and places that perpetuate division. OSCT events are useful in opening up people's eyes to what could be, but the value is diminished if there are no ongoing interventions sustaining this new understanding. Interventions that tackle the everyday systems supporting the divisions are needed to supplement the interventions of OSCT events. This will add substance between events and enhance the value of the events themselves.
454

A socio-ecological analysis of environmental change in the Kannaland Municipality of the Klein Karoo, South Africa, over the last 100 years

Murray, Amy Louise January 2015 (has links)
This study utilizes a cyclical socio-ecological systems approach to explore change in natural vegetation and land use within the Kannaland Municipality of the Klein Karoo. Repeat ground photography, historical climate and agricultural data, and in-depth, semi-structured interviews were used to assess environmental, political and socio-economic change in the study area since the early 1900s. Few studies have had the opportunity to augment the analysis of repeat ground photography with contextual information from in-depth interviews making this study unique in its approach. For most of the 20th century agricultural land use within the Klein Karoo has undergone fluctuations of increased and decreased productivity. However, during the later decades a noticeable decline in agricultural land use, especially sheep and goat production, has been recorded. Largely due to this, and contrary to degradation projections for this area, evidence of growth in cover of natural vegetation, especially over the last 20 years, was found. From the mid 1990s change from largely agricultural to recreational game and weekend farming as well as tourism-related land use has increased. Implications of recent land use change are perceived as both positive and negative. Increases in natural vegetation cover and potential associated biodiversity improvements are considered positive implications associated with the demise in extensive agricultural land use for the area. A decline in farm-based employment and agricultural productivity are considered negative implications of this land use change. Substantial increase in game farming within the study area is perceived to require stringent monitoring and research into the long term implications of this land use on natural vegetation. For optimal land use management and conservation of natural vegetation this study recommends building the capacity of the agricultural and conservation extension services within the Klein Karoo. The study further promotes the diversification of land use inclusive of agricultural production, conservation of biodiversity and development, particularly within the tourism sector, as optimal for the sustainability of land use in the Klein Karoo.
455

From fork to farm: understanding Kitwe's food system through the fish lens

Siyanga-Tembo, Fridah January 2017 (has links)
Food production has been a constant feature of food security policies. This narrative has continued despite findings showing that food insecurity is structural, and more driven by issues of access than availability, particularly for low-income households in cities who live in a cash economy. While usually considered a rural issue, the urban poor with low and unreliable incomes also face food insecurity which manifests differently to that of their rural counterparts. Thus, this creates the need to understand how the urban poor get their food. Garneton, a low-income area in Kitwe, Zambia, was chosen as the case study area for understanding the food system that feeds the urban poor. Fish and the fish value chain were used as the lens with which to understand the food system. The primary aim of the study was to understand the flow of fish in the food system and how it gets to low-income households in Kitwe. A qualitative methodology using semi-structured in-depth interviews was used. A bottom up and systems approach which started by finding out what the low-income consumers ate, and following the fish value chain systematically up to the producers enabled the study to capture the actual food system that feeds the poor and uncovered the different issues affecting the food system. The study had three main findings. The first finding was that the low-income households bought their food from both formal and informal markets but were more highly dependent on the informal markets. The factors that drove their purchasing decisions included income, proximity and volumes of fish sold. Secondly, the study also found that informal traders bought their fish mainly through the informal markets although the imported fish was bought from the formal market. Thirdly, the study found that there were a number of factors that affected the food system. These included policy, economic and environmental factors. The pathways of fish were also found to change in accordance with the fish ban. The thesis argues that, there is greater need to have policy that addresses the needs of the urban poor. Food should also be looked at as a cross cutting issue with different food systems perceived as complementing each other to addressing the food needs, particularly of the urban poor. Finally, more attention must be paid to the informal market which plays a significant role in meeting the food security needs of the urban poor.
456

An investigation into the relationship between information and environmental behaviour : a case study of Cape Town's Smart Living Campaign

Buckton, Karl January 2015 (has links)
Environmental campaigns have generally relied upon using information alone as a way to get messages across to the public. This approach is based on the assumption of a linear relationship between information and behaviour: it is believed that educating people will lead them to be more environmentally responsible. An example of this is the information deficit model. The information-deficit model (Blake, 1999), suggests that experts inform individuals about the environment in order to achieve behaviour change. Contrary to this model, dissenters claim that the information-deficit model is not participatory or deliberative and that human behaviours are determined by factors such as individual lifestyle. This dissertation tests the assumption behind the idea that added information leads to improved environmental behaviour. The research used a case study of an urban South African environmental education program: the Smart Living Campaign in the City of Cape Town. The study is split into two sections, the first which focuses on the workplace of the companies. The second which is aimed at the households of the employees of the companies. The study focused on two variables, the impact of waste management in terms of recycling, and energy usage in terms of electricity consumption on their behaviour.
457

Applying water footprint assessment with the aim of achieving sustainable water resource management at a large commercial beef cattle feedlot in Gauteng Province

Pearce, Lisa January 2016 (has links)
The commercial production of beef meat is associated with a wide array of environmental impacts, and is itself very sensitive to environmental conditions. Water in particular is a critical environmental resource and the commercial success of an agri-business is closely tied to reliance on fresh water resources. In an economic sector that is increasingly faced with competition for resources as well as negative public opinion about environmental impacts, the management of water-related risks and impacts is essential to ensure business resilience and sustainability. Global trends in animal production are causing the environmental problems to become more harmful, and intensive animal production is being separated from traditional crop farming systems where manure could be used as a fertilizer to replenish soil nutrients. There is a spatial disconnect in the production value chain brought about by commercial trends. An on-site water efficiency approach to water resources management of an agri-business does not enable it to evaluate value chain water-related risks, or its' own contribution to sustainable water use in the catchments where raw materials are produced and production wastes are distributed. The question of sustainable water use within the production value chain of beef meat is not solved with an on-site efficiency approach to water resources management because the approach is inadequate in evaluating the freshwater environmental impact, or in managing water-related business risks of the whole beef production value chain. It is argued that a systems approach is more credible because it allows a beef cattle feedlot enterprise to evaluate freshwater impacts across the production value chain and will enable a feedlot to transition towards a sustainable value chain water resources management model The Water Footprint of food, goods and services is a volumetric expression of the water that is consumed during the production process. Unlike water use, the water footprint refers to water that is imbedded into a product (also referred to as virtual water) or otherwise made unavailable for further use within a catchment, province or country through pollution dilution. The Water Footprint Network developed the Water Footprint Assessment and describes three types of WF: the green water footprint refers to evaporated water, typically in the form of rainwater. The blue water footprint refers to water that is abstracted from a resource and delivered to the point of use, for example in the case of irrigation from a river, borehole or dam. The grey water footprint is a volumetric expression of the amount of fresh water required to dilute chemical substances to a safe or acceptable concentration in the natural environment. A Water Footprint Assessment (WFA) was undertaken at a beef cattle feedlot in Gauteng, South Africa. The WFA focused on the Bovine WF of the 4-month winter- and summer finishing periods that cattle spend at the feedlot. The second focus was on the monthly grey WF of waste management activities at the feedlot. The purpose of the study was to determine how the application of a WFA would enable an agri-business to transition from an on-site approach to water resources management, to a value-chain systems approach to sustainable water resource management.
458

Environmental Initiatives within Canadian Christianity: Exploring Obstacles and Opportunities

Siegrist, Anthony 03 February 2022 (has links)
This qualitative study adds to our understanding of the obstacles and opportunities experienced by Canadian, Christian organizations relative to their engagement in environmental initiatives. The core of this inquiry was comprised of sixteen in-depth, semi-structured interviews conducted with representatives of denominations and humanitarian agencies. Interview questions and the initial coding categories were drawn from the findings of an auto-ethnographic study by Haluza-Delay (2008). The wider relevance of Haluza-Delay’s findings was explored by engaging a broader population and by using a more consistent methodology. While this study largely confirmed Haluza-Delay’s description of the obstacles and opportunities facing Christian organizations relative to their engagement in environmental initiatives, it also identified an additional set of issues. Political polarization and shrinking resources, previously unidentified barriers, were evident in the data gathered. Occasions to hear from new voices, especially those of indigenous persons and individuals from the global South, were previously unidentified opportunities. Finally, this study found that several of the Canadian, Christian organizations represented by interviewees were undergoing a transition in their understanding of Christian mission, thereby creating new possibilities for environmental engagement.
459

From drought to desalination: The case of Cape Town

Beerthuis, Sharda 08 February 2022 (has links)
The recent Cape Town drought and fear of a severe water crisis between 2015- 2018 was followed by a fast-tracked crisis management response. In line with a wider global trend, the City of Cape Town adopted a technology called ‘reverse osmosis desalination' into the water supply mix. This ‘water production' technology is alluring as it promises to be ‘drought- proof', preserving a constant flow of water in times of increased climatic uncertainty. Yet, the implementation of water technologies in Cape Town continues to be a highly debated topic. Cape Town suffers from a longstanding legacy of uneven racialized infrastructure development practices, resulting in unequal water access and consumption. In this context of unequal water security across social groups and increased climatic vulnerability, it is important to carefully consider the implications of new water technologies if the desired outcome is a more sustainable and equitable water future. Drawing on urban political ecology, this dissertation explores the process in which the instalment of three temporary desalination plants and planning for permanent desalination in Cape Town emerged. This, in order to carefully consider its consequences for equitable water security. By utilizing secondary official city documents, reports and news articles from several credible news platforms, supported by a number of personally conducted semistructured interviews and secondary sourced interviews with City employees, this thesis aims to understand how desalination is constituted as a crisis response. This exploration is organized around analyzing the relationships and dynamics between various actors, the events that signified the processual nature of the adoption and the emergent effects for water access across the City. The findings reveal that the promise that desalination holds as a technical solution to climatic uncertainty undermines the / contradictions that evolve alongside the instalments. While desalination was pushed by the municipality as a drought relief technology for all citizens, the results show that the emergence of this technology came with frictions, as it was contested, ecologically disturbed and critically questioned by multiple actors. As my findings demonstrate, desalination triggers the emergence of exclusive decision-making processes and financial constraints, especially for vulnerable citizens. This thesis thus argues that desalination implies to only secure water for some, while intensifying water insecurity for the already vulnerable. While the City strives towards a “shared water future”, the high focus on extending its water supply to meet growing demands lacks consideration of meeting existing demands, excluding the socio- political processes within current water decision making. This rather reinforces racialized- spatial and distributional inequities across a diverse range of social groups within the City.
460

Township churches as heritage: The case of Langa, Cape Town

Irrgang, Berendine January 2015 (has links)
This study investigates the perceived heritage significance of township churches. This is done by means of a case study which focuses on early churches in Langa, particularly the Wesleyan Methodist and the African Methodist Episcopal churches. The hypothesis is that heritage values are attached to certain churches of Langa and that these are regarded as heritage resources as a result of a particular character or built form. In support of this hypothesis, the intellectual realm of churches and heritage values was explored and the historical and spatial context which informed the development of the churches, investigated. A strong emphasis was placed on ascertaining the heritage values of the Langa community in a series of interviews. To understand the values attached to churches, views have been solicited from community members residing in the neighbourhood of the identified churches, members of the clergy and congregants and a number of 'experts’ - people who have been involved in the study of heritage in Langa, either from an academic or community perspective. Sixteen interviews, which took the form of focused, semistructured discussions, were conducted.

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