3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Images of a culture of diversity in a South African organisation(2008-10-22T11:26:36Z) Pillay, ShanyaThis study was interested in assessing whether any disparity between formal policy and employee experience exists within a South African organisation. Specifically, the research identified the images and metaphors presented within an organization’s formal policy documents on diversity and then assessed the extent to which those images reflect a culture of diversity within the organisation. The researcher made use of qualitative methods in the form of content and discourse analysis and in-depth interviews. The results suggest that while the images and metaphors found in policy documents do in fact represent a culture of diversity in its stated intentions, practically, as experienced by employees, a culture for diversity remains limited.Item The design of a risk assessment model to determine the impact of the herbal medicine trade on the Witwatersrand on resources of indigenous plant species(2008-08-08T10:11:27Z) Williams, Vivienne LindaExploitation of botanical resources has resulted in significant decreases in the sizes of some plant populations, especially for species that have a high commercial value and are important to the lives and livelihoods of rural communities. Medicinal plant resources are used and traded commercially in both rural areas and urban centres, and over-exploitation has become a deterministic factor in the extinction risks to certain species. The main aim of the study was to design a risk assessment model to determine the impact of the medicinal plant trade on the Witwatersrand (centred around Johannesburg) on indigenous plant resources. The goal was to incorporate trade variables correlated with harvesting risks together with biological characteristics of the harvested species to predict which species are most threatened by the trade and are thus high on the list for conservation priority. The study required semi-quantitative surveys of the medicinal plants sold by traders in the Witwatersrand to be conducted. In 1994 and 2001, the plants sold in 50 muti shops and by 100 vendors in the Faraday Street market respectively were inventoried. Quantitative trade data were also captured, including volume, pricing structures and plant size (e.g. bark thickness and bulb diameter). A scientific sampling strategy was adhered to throughout the study to add statistical validity to the results. In a novel approach to analysing ethnobotanical data, the frequency of plant occurrences in the markets was analysed using measures (analysed by EstimateS) of species diversity traditionally used in ecology. The measures allowed for sampling strategies and sizes to be compared between data sets and for the number of species likely to be sold in the region to be estimated. Furthermore, data sets could be compared in terms of species richness, diversity, evenness and complimentarity. Another novel approach taken in the thesis was to estimate the number of individual plants harvested annually by gatherers, specifically the number of trees that are debarked and the number of whole bulbs that are removed. In order to estimate the number of trees debarked, a study was conducted to determine the relationship between bark thickness and stem diameter for six species. The results made it possible to estimate the condition of the resource in the wild from market records (i.e. bark thicknesses) and to see how the availability of larger trees has declined for species such as Warburgia salutaris between 1994 and 2001. Results for bulbs showed that there has been a significant decrease in the diameter of Eucomis autumnalis bulbs present in the markets in the same period, suggesting significant levels of resource depletion. The thesis explored the use of a multivariate methodology for assessing the extinction risks of species and assigning species harvested for the medicinal plant trade to various hierarchies of risk and conservation priority. Hierarchical and non-hierarchical cluster analysis (Ward’s and K-means respectively) methods were found to be effective in assigning species to clusters of similar risk and conservation priority. From a combined list of 392 ethnospecies recorded in the muti shops and Faraday market, a short-list of 119 higher risk species was identified using four to five trade variables. This list was further reduced to 87 species to ascertain conservation priorities based on the additional inclusion of seven biological variables in the assessment. From this list, approximately 31 species were identified as having higher conservation priority and would be candidates for further research, management and protection within the ambit of conservation and sustainable utilisation programmes. These species would further benefit from Orange Listing or having their IUCN Red List status re-evaluated. The methods developed in this study are recommended for other ethnobotanical studies. Furthermore, the risk assessment method could be applied to the assessment of species similarly traded in other medicinal plant markets or applied to the assessment of species under threat from other stressors at a regional, provincial and/or national level using the appropriate variables.