3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Detecting soil properties in agricultural lands using field spectroscopy and regression models(2020) Zahinda, Franck MugishoReflectance spectroscopy can be used to non-destructively characterize materials for a wide range of applications. In this study, visible-near infrared (Vis-NIR) spectroscopy was evaluated for the prediction of diverse soil properties (clay content, SOC, TN, and pH) related to different soil samples from the Eastern Cape Province in South Africa. Soil samples were scanned by a portable spectrometer at 1 nm wavelength resolution from 350 to 2500 nm. Calibrations between soil properties obtained from digital soil maps and reflectance spectra were then developed using cross-validation under partial least squares regression (PLSR) and support vector machine regression (SVMR). Raw reflectance and Savitzky-Golay first derivative data were used separately for all the samples in the data set. Key wavelengths to predict clay content, SOC, TN, and pH were identified using the variable importance projection (VIP) and Boruta algorithms. Data were additionally divided into two random subsets of 70 and 30% of the full data, which were each used for calibration and validation. The results indicated that Vis-NIR spectroscopy can be successfully used to predict soil clay content, SOC, TN and pH. For clay content, SOC, and pH, the best results were obtained by SVMR with first derivative data (RPD = 2.05, Rp2 = 0.83, RMSEP = 1.95% for clay content; RPD = 2.40, Rp2 = 0.87, RMSEP = 2.48 g.kg-1 for SOC; and RPD = 2.87, Rp2 = 0.89, RMSEP = 0.16 for pH). In contrast, PLSR with raw data outperformed SVMR models for TN prediction (RPD= 2.15, Rp2 = 0.77, RMSEP = 0.20 mg.kg-1). Key wavelengths to predict the four properties were identified mostly around 400-700 nm and 2200-2450 nm. In conclusion, Vis-NIR spectroscopy was variably good in estimating clay content, SOC, TN and pH in laboratory conditions, and showed potential for substituting traditional wet laboratory analyses or providing inexpensive dataItem Agro - pod an ecosystem of agriculral knowledge exchange in the Groblersdal area, Limpopo(2018) Sithole, Lebogang SinahThere are many threats facing the world’s population. Population growth, global warming and especially food security are challenging the conventional methods of food production that have used for centuries. These methods continue to impact the earth negatively and its ecosystems, hence the prevalence of the devastating effects of climate change on the earth. The resulting effects, coupled with our continued use of fossil fuels to keep up with a growing population can only harm the earth even further and therefore harm our very existence. My chosen site is an abandoned location along a T-junction just outside the town of Groblersdal in Limpopo. The site is already populated with street vendors who originate from the rural area surrounding the towns in the district. These vendors sell fresh produce sourced from the surrounding commercial farms. I find myself confounded by these vendors and their lack of produce variety and always wonder how they sustain their businesses with this typology. What especially bothers me about this dynamic is that these rural communities have been farming traditional crops historically and these highly nutritious crops have managed sustained to sustain them and their ancestors for centuries. These rural communities are native to the places where the crops are grown (or have become part of the culinary culture over time) and these crops are particularly well adapted to the prevailing conditions. With all this considered my intention is to design a self-sustaining hybrid agricultural support center and training facility. This facility will utilise community participation in the building process to promote economic empowerment and the preservation of local vernacular architectural methods and techniques. The programme aims to be inclusive in order to allow for all stakeholders to gain and impart knowledge, promoting a cycle of knowledge exchange By employing sustainable architectural interventions such as rainwater and energy harvesting, passive cooling systems and the preservation and re-use of resources, the architecture can become a transformative mechanism for change in the rural context and restore the pride of the Pedi peopleItem Exploring the implications of institutional fragmentation and the role of community participation in sustainable natural resource management in Zambia: a case study of Lochinvar National Park(2018) Mwale, ChandaZambia as a country has a considerable amount of land dedicated to the protected area network. It has been argued that this quantity of land resource under protection has not resulted in the desired quality of progressive natural resource management that yields benefits for people and nature. The legislative framework allows for interface of varied stakeholders to take part in the management of natural resources but this is yet to be achieved in a manner that benefits both resource managers and stakeholders. The majority of game management areas which are the mandated interface between ecological needs and social needs are often over exploited or without management plans that are adhered to, rendering them gateways to encroachment of national parks. The main aim of this study was to investigate the extent of institutional fragmentation in natural resource management and the role of community participation. The main methods utilized to investigate this were qualitative with use of mainly semi-structured interviews. The research findings indicate that although there are opportunities to sustainably manage the resources in and around Lochinvar National Park with community participation, this remains limited due to a number of reasons like: institutional fragmentation, cultural practices, lack of community benefits and a poor understanding of enabling participatory legislation. Community Based Natural Resource Management is a term that is not foreign to Zambian resource management as it has been a part of conservation circles for at least 4 decades. The successes of it however, seem few and far between. This study shed light on some of the factors that might be contributing to the limited success of CBNRM in Zambia. Recommendations of this research include: focus on governance rather than government pushing the NRM agenda, private sector involvement in management of natural resources, broadened community structures involved in management of natural resources management. Key words: natural resources management, community based natural resources management, governance, common pool resources, Zambia, Kafue Flats, legislative framework.Item A food sovereignty critique of the G8 New Alliance on food security and nutrition(2016-03-03) Crankshaw, AmyThe G8 New Alliance on Food Security and Nutrition (NAFN) is a new, under-researched and rapidly spreading partnership initiative. As the latest attempt to target hunger in Africa by developed countries, it deserves a certain level of scrutiny to decipher the intended development trajectory for African food systems and the possible implications for smallholder farmers, since these smallholders produce more than ninety percent of the continent’s food supply. Food sovereignty provides the ideal lens through which to analyse the New Alliance, being a political economy critique of agro-industrial food systems, as well as a constitutive approach to rights and the building of a grassroots movement and alternative. This research seeks to ascertain how the New Alliance may globalise African agriculture and undermine food sovereignty. An exploratory research design was used, first historicising African globalised agriculture, then decoding the main objectives of the New Alliance, and finally using the African Food Sovereignty Alliance as a case study to critique its translation into African countries’ commitments. The first few predictions of the hypothesis were strongly validated with findings that the New Alliance will result in large-scale investment of land, the commercialisation of the seed industry and an increased use of agro-chemicals and GMOs, increased foreign investment, and monopolisation of agribusiness by MNCs. To a lesser degree, the prediction that it would decrease barriers to trade and increase imports and exports was confirmed; however, there was little evidence that it intends to cut domestic support measures like some previous development programmes. The New Alliance is beyond reform, built on flawed neoliberal assumptions about development. This and further research could contribute to a movement to abolish the New Alliance before it induces negative long term effects, and to warn off other African countries contemplating this initiative.