The present study aims to examine the history, role and functions of trading in Soweto. The study documents the development of black trading in South Africa from the turn of the century to the mid-1980s. The imposition of increasingly restrictive legislation and negative attitudes towards black trading through the mid-1970s led to the development of small-scale, illegal trading operations, especially hawking. During the 1980s the restrictive legislation was relaxed and attempts, both legislative and financial were made to foster black business. The contemporary structure, form and functions of Soweto as an entity, and as part of metropolitan Johannesburg, are outlined. This is used as a backdrop to the discussion of the legislative constraints and case study analysis of trading in Soweto. The literature review examines the contributions of both the diffusionist paradigm and its offshoot, reformism, as well as various strands of the Marxist paradigm to studies of trading in Third World situations. The chapter then turns to an alternative construct, structuration, as a framework within which to place the study of trading in Soweto. The core of the study is a case study of trading in Soweto. To this end both traders and consumers are scrutinized and traders are ranked along a continuum from petty traders, small-scale and of ten illegal and mobile; to large-scale, formal, sanctioned traders. To carry out this analysis four areas were selected from the townships of Soweto, in pairs of contrasting socio-economic levels, and with two of the areas containing nodal concentrations of shops. The areas are Diepkloof, Dube, Moletsane and Pimville. Questionnaire interviews were conducted with consumers selected by systematic sampling of houses in the pre-selected areas, with traders operating from formal business premises, who were identified through the consumer survey and through fieldwork. The case study profiles the characteristics of formal 'and petty traders and investigates the differences in character between food, clothing and alcohol traders. Next is an investigation of the traders in Soweto in the context of metropolitan Johannesburg. An attempt to determine the degree to which petty traders are functional or alternatively dysfunctional to capital (i.e., formal enterprises) is undertaken. The theory of structuration is explored to investigate the actions of actors, namely traders and consumers. Legislative, economic and political institutions are examined as structures which may be both constraining and enabling for these actors under different circumstances. It is concluded that considerable diversity exists among the traders in Soweto and that, although government policy has moved from repression to active support of black businesses, the actual number of "formal" traders in Soweto has declined in recent years. The functionalist argument that petty traders provide low-cost goods which sustain the low wages paid to employees of formal enterprises, is not borne out by the data. It is felt, however, that the State benefits from the existence of petty traders as they ameliorate the need for a well- developed welfare system. Similarly, this group's demonstrated capacity to produce employment opportunities is seen as a survival strategy rather than part of a sustained development of the urban economy. The analysis of the actors in the context of structuration in this study adds an important dimension to research beyond that offered by structural-functionalist accounts of the Marxist paradigm. Future research on trading in Soweto and in other geographical locations may be profitably enhanced by the adoption of a structurationist perspective.

Includes bibliographical references (leaves 112-126). / This thesis investigates characteristics of the summer rainy season over the Limpopo region that are important to the agricultural sector and other user groups. The Limpopo region supports a large rural population dependent on rain-fed agriculture as well as significant biodiversity, particularly in the Kruger National/Limpopo Transfrontier Park and is vulnerable to severe flood and drought events. REcently, the region has been impacted by severe drought (2002-2004) and flooding in late summer 2000. The rainy season characterisitcs investigated are the frequency of wet and dry spells during the rainy season and the onset date of the season.

Includes abstract. / Includes bibliographical references (leaves 132-145). / Mineral aerosols emitted from arid and semi-arid regions effect global radiation, contribute to regional nutrient dynamics and impact local soil and water quality. Satellite imagery has been central to the identification and determining the distribution of source areas and the trajectories of dust around the globe. This study focuses on the dryland regions of Botswana, Namibia and South Africa. It uses the capabilities of the ultraviolet channels provided by the older Total Ozone Mapping Spectrometer (TOMS), the Ozone Monitoring Instrument (OMI) (a TOMS follow up), the visible bands of Moderate Resolution Imaging Spectroradiometer (MODIS), and the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard Meteosat Second Generation (MSG). This study compares various dust detection products but also focuses on the application of thermal infrared bands from MSG through the usage of the new "Pink Dust" visua lisation technique using channels 7 (8.7 ~m), 9 (lO.8 ~m), and 10 (12.0 ~m). This multisensor approach resulted in a regional maps highlighting the distribution of source points and establishing some of the prevalent transport pathways and likely deposition zones. Southern African dust sources include a few large and many small pans, subtle inland depressions and ephemeral river systems, which are subject to a range of climatic conditions as part of the Kalahari and Namib region. This work in particular examines if source points are productive due to favourable climatic conditions. The debate around transport limit verses supply limit can only be solved at the local scale which requires observation at higher spatial and temporal resolution as provided by the latest dust detection products. MSG and MODIS in particular have shown distinct source point clusters in Etosha and the Makgadikgadi Pans which based on the courser resolution of older TOMS, have so far been treated as homogeneous sources. Data analyses reveal 327 individual dust plumes over the 2005-2008 study period, some of which are more than 300 km in length. These are integrated into existing climate and weather records provided by National Centers for Environmental Prediction (NCEP) data. The results identified a set dust drivers such as the Continental High Pressure, Bergwinds, Tropical Temperate and West Coast Troughs, and Westerly and Easterly Wave lows. This enhances our ability to predict such events, in particular, if transport acts as the limiting driver. Some of these find ings also have the potential to enhance our knowledge of the aerosol generation process elsewhere. The quality of findings are still limited by problems associated with dust plume substrates and clearly require significant surface validation relating to hydrological and climatic controls at the micro-scale. It is furthermore evident that no current instrument fully meets the requirements of the mineral aerosol research community.

In 2009, the City of Cape Town (CoCT) adopted a stormwater policy which mandates that new and existing developments should reduce the concentrations of phosphorus and suspended solids in stormwater runoff by 45% and 80% respectively, but offered no explicit guidance about how these water quality targets might be achieved. This study aims to contribute to the limited knowledge that exists about the performance of local plant species to treat stormwater.

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.

When Europeans settled in South Africa in the 17th century, maize was already being grown as part of diverse and traditional cropping systems. Over centuries maize has become embedded in a web of social, ecological, economic and political relations. Since the 1900s the development of maize seed has increasingly shifted location as scientific maize breeding has come to dominate its production. In this time maize seed has changed form, from open pollinated varieties (OPVs) to hybrid seed, and most recently to genetically modified (GM) seed. While the progression of seed developments alongside their co-technologies such as pesticides, fertilizers and herbicides has greatly boosted yields, the development of maize has become increasingly generic and disconnected from the specificities of local agroecosystems. Like all technologies, maize seed technologies are not neutral but are rather deeply entangled in the history and politics of knowledge production. Commercial technologies such as hybrid and GM seeds are products of a particular lineage of thought rooted in the post-enlightenment age of modernist, dualist science. This has resulted in a conceptual dualism in which humans are seen as separate from nature. Studies on the impacts of new seed technologies have tended to replicate this dualism, focusing either on social or ecological aspects. Few investigate the effects on relationships between humans and agro-ecosystems. This thesis aims to address this knowledge gap by exploring the effects of the technification of maize seed on knowledge and practices within two sites of agricultural knowledge generation and practice in South Africa: smallholder maize agriculture and maize research and development. These offer two unique sites of knowledge creation and practice, and historically have had a turbulent relationship, rooted in colonialism and apartheid histories. Through exploring human-agroecosystem interactions, the research hopes to contribute to a broadened understanding about the impacts of maize seed technification and implications for agricultural knowledge generation and sustainability. Drawing conceptually and methodologically on posthumanist theory, this thesis investigates the changing nature of social-ecological relationships of and between smallholder farmers and scientists and the agro-ecological systems in which they work. Building on the concept of agricultural deskilling, it argues that modern seed technologies have contributed to ecological deskilling both on smallholder farms and within research and development, as seed technologies become increasingly disconnected from the environments in which they are used. 2 Increasingly, however, there is renewed interest by both farmers and scientists in ecological-reskilling as new ‘silver bullet' seed technologies reveal many setbacks. The thesis concludes that in order to rebuild displaced ecological knowledge an ontological shift is needed to move beyond dualist science-based approaches to farming and research, towards those that learn from relational ways of knowing. Approaches should be embraced that acknowledge the relational knowledge of smallholder farmers that has been displaced and devalued for centuries and that builds this relationality into research. This c could contribute to restoring cognitive justice and fostering more resilient agricultural futures.

This study examines the expansion and utilisation of Fadama irrigation in the Sokoto Rima River Basin using the ground yield and remote sensing data. Decadal land use land cover (LU/LC) change detection was conducted using remotely sensed data from Landsat 4,5,7 ETM for 1988, 1998 and Landsat 8 OLI for 2018 using a digital classification and a cloud-based classification provided by Google Earth Engine (GEE) API, with an overall accuracy of 97% in 1988, 92% in 1998 and 90% in 2018. Additionally, the Normalised Difference Vegetation Index (NDVI) derived from MODIS, GEE NDVI, and the Landsat was used to assess the crop yield patterns of the irrigation farming at the Fadama sites in conjunction with the limited ground yield data from 2000-2005, and was found to be a positive change over the years. The result generated from the classification was juxtaposed with observable field characteristics of the LU/LC identified. The decadal trend between 1988 to 1998 saw an increase of 114% in dam surface water and 166% of the natural vegetation, while the nonvegetated areas and the Fadama areas decreased in size by -100% and -65% respectively. Between 1998 and 2018, the reverse of the previous pattern was observed, with water and vegetated areas decreasing in their surface area in hectares by -80% and -23% respectively. Non-vegetated areas increased by 3% while Fadama areas increased in size by 112%, indicating that the Fadama areas were under-utilised by - 65% of the total hectarage in the past, and in recent years a 47% increase was recorded between the two periods. In addition, the Standardised Precipitation and Evapotranspiration Index (SPEI) data from 1950 was used to analyze the meteorological and hydrological drought pattern at four locations within the basin and was found to be a moderate drought. The SPEI data was then correlated with the Global Surface Water Explorer data to observe the surface water dynamics and to show the drought extent around Bakolori, Goronyo, Jibia, Wurno and Zobe dams. The result showed that the dams are shrinking in size due to risen temperature and consequent evaporation caused by moderate drought and water use for irrigation. Lastly, this research uncovers the utilization of the Fadama in recent years by 47%, but with mismanagement of the resources in the Sokoto Rima River floodplain because not all the irrigation fields are put into cultivation, with 39,907 ha put into use from the planned irrigation of 105,472 ha in the entire basin. Therefore, this research recommends a proper intervention of the government to promote and enhance sustainable management of the Fadama lands, water, and the vegetation resource. This should be done in consideration of the deteriorating climate to close yield gaps, with much emphasis on engaging the local farmers by monitoring yearly ground yield data and ensuring all incentives are distributed effectively to brace an active and sustainable management of the entire basin and its vast resource.

The City of Cape Town's integrated housing database is used to manage the allocation of state housing across the city. It is a technical intervention in a contested and politicised context. On the surface, it appears to be an effective state tool that determines eligibility for housing assistance, and subsequently, the implementation of fair housing allocation practices. This veneer of technicality, however, conceals the complex state work involved in the production, maintenance, and use of the database. In the context of South Africa's transition from apartheid to democratic modes of governance, this research examines the database to engage with the state's work in producing tools for legitimate decision-making. As a state tool, the database and its functioning has been largely rendered invisible, either dismissed because of the opacity of its functioning, or positioned as a political myth, a smokescreen that conceals the state's inability to deliver on its housing promises. However, a technopolitical lens challenges researchers to pay attention to the form, function and development of state tools; nuances that are too often overlooked. In this research I therefore examine the housing database as a legitimate state tool for fair housing allocations. Using archival material, I explore the making of the database. Based predominantly on interview material with key informants, I investigate the production of the data held within the database. I consider, through policy and document analysis, the use of the database and its data in the actual practice of housing allocation decision-making. In sum, the research tracks the ideological, political, bureaucratic, and technological shifts that have shaped the database over three decades of housing allocation reform. Through this analysis of the development, form, and function of the database, I substantiate the ways in which the database works as a mode of governance, crafted by the state, that builds and sustains housing allocation decision-making. Demystifying the database as a state tool highlights its gradations, textures and contradictions. Its analysis makes visible the state craft that is key to its development, form, and function – what shapes the state's housing allocation decision-making. This analysis opens up the South African housing crisis beyond the impasse where citizen need exceeds the state's capacity to supply houses, and shifts the narrative away from an ambivalent, unwilling or uncaring state, to one that makes visible and describes the state's craft on housing allocation decision-making.

The utilisation of wild products is a mainstay of household livelihoods for millions of forest and rural dwellers worldwide. While many are used for subsistence purposes, some wild products are also exploited commercially. Commercialisation has often coincided with state-led conservation strategies that have brought previously unregulated resources under state regulation. Mopane worms are a caterpillar phase of the Imbrasia belina moth, used as a household food source and, increasingly, part of a lucrative cross-border trade in southern Africa. Across Botswana and South Africa, the statutory regulation of these resources is overlaid upon customary forms of governance that continue to regulate resource access and use. The effectiveness of such interactions is important for the success or failure of different governance arrangements and resource-based livelihoods. Using the cross-border trade of mopane worms as a lens, this research examines the ways in which actors navigate different governance systems, including the complexities of informal trade. In doing so, the research aims to improve understanding of the implications of the interplay between different governance arrangements and informality and their influence in configuring access to resources and cross-border markets. A key finding is that the inadvertent consequence of integrating multiple forms of governance and resultant interactions has led to the emergence of constraints that impact resource users across the cross-border trade chain. Interactions between statutory and customary governance systems have, in turn, led to the emergence of informality as an adaptive strategy across the trade. The study demonstrates that the informal and cross-border nature of mopane worm trade compels actors to use their agency to adopt multiple strategies to navigate complex governance arrangements. This in turn results in an uneven distribution of constraints and opportunities across the trade chain. Power imbalances shape diverse and complex forms of social relations, affect access to resources and markets, and marginalise destitute actors. Fragmented governance arrangements benefit actors with privileged access to market information, knowledge, capital, and resources, enabling them to navigate the constraints and incompatibilities that characterise informal cross-border trade. The study underscores the need to streamline statutory, customary, and informal governance approaches particularly as the three systems are not separate but dynamic, and to pursue an unambiguous, pro-poor agenda, focused on safeguarding informal, resource-based livelihoods and the sustainable use of mopane worms.

The specificities of the African decision context are not well understood and are often not considered in the development, tailoring and supply of climate services for Africa. Yet, the utility of climate services relies on them being suitable for the decision context, so an understanding of the decision context should be central to climate services development. One unexplored approach to deepening an understanding of the decision context for climate services is through climate change risk perceptions, because perceptions of climate change risk influence whether decision makers take action on climate change as well as what information they seek and use to take action. Accordingly, this study uses data collected through a regional survey (N = 474) and semi-structured interviews (N = 36) to explore and better understand climate change risk perceptions amongst policy decision influencers in east Africa. The data informs three separate analyses. First, a climate change risk perceptions model is constructed, elucidating how various risk perception determinants interact to influence climate change risk perceptions and professional action on climate change in east Africa. This model shows that the pathway to climate change risk perceptions differs depending on individual value systems. Heightened climate change risk perceptions of those with primarily self-enhancing (inward looking) values are predominantly influenced by social norms, whereas heightened climate change risk perceptions of those with primarily self-transcending (outward facing) values are predominantly influenced by experience of extreme events and the psychological proximity of climate change. Second, the identified climate change risk perception determinants are quantified and explored to better understand the specificities of the decision context in which climate services are used. Climate change risk perceptions are found to be heightened, driven by observance of social norms, perceptions of climate change as a proximal risk, frequent experience of extreme weather events and a predominantly self-transcending value system among policy decision influencers. Lastly, the relationships between determinants of climate change risk perceptions and the use of climate services information are quantified and explored to evaluate gaps in currently available climate services. The analysis reveals three main gaps, namely the lack of long-term climate change projections disseminated through National Meteorological Services, the limited locally ground-truthed delivery of impact-based forecasts and inadequate capacity development of climate services users to understand and use complex climate information. The study culminates in a proposed framework for the enhancement of climate services for east Africa, based on understanding gained through the study.