M.Sc. (Geology) / Three anomalous borehole core sequences from the north eastern Karoo Basin are examined. The boreholes are located up to 30 km from each other and are lithostratigraphically completely atypical for the Vryheid Formation, Ecca Group, Karoo Supergroup. The lithologies of the three boreholes are intensely brecciated for the most part, while all of the surrounding boreholes reveal normal stratigraphy; their sedimentary strata are normally horizontal with no faulting present. The only known disturbances to the Vryheid Formation in the study area are the occurrence of intrusive mafic dolerite sills and dykes, which are known to have been contemporaneous with and immediately following the eruption of the Drakensburg Group basaltic lavas. The borehole core lithologies are described in detail with reference to their textural, mineralogical and petrographic characteristics. Mineral and bulk rock chemical data are presented. Several modes of origin of the brecciated core sequences are considered, with the primary hypothesis that the brecciation is due to diatreme activity. A review of diatremes and their mode of emplacement is proposed with reference to their occurrence within the Karoo Igneous Province, as some diatremes in the Karoo are associated with dolerite sill emplacement. The isolated occurrences, lithologies, petrography, alteration and geochemistry of the sequences are used to argue that the Vryheid Formation, intersected in the form of the three anomalous boreholes, was disturbed by diatreme activity, which are genetically related to the late dolerite sill emplacement into the Karoo Supergroup rocks.

Thesis (M.Sc.(Agric.))(Agricultural Economics)--University of Pretoria, 2007. / Includes summary. Includes bibliographic references (leaves 96-100).

Children are a highly susceptible population to the effects of air pollution. To establish a current baseline of child respiratory health and associated risk factors in the Highveld Priority Area, a quantitative questionnaire was carried out among parents or guardians of children aged between 9 and 11 years in Witbank and Middelburg. Key health outcomes of interest were asthma and upper and lower respiratory tract complications. Air quality data were obtained for Witbank and Middelburg and compared with recently gazetted National Standards to establish potential risks. The prevalence of health outcomes and associated risk factors, such as indoor fossil fuel burning and parental smoking were considered and key risk factors identified. A unique method for the analysis of poor quality responses was introduced in order to derive the most meaning from the data. The study findings showed the air quality to be of concern particularly in Witbank; however, it also showed a similarity between the air quality in both towns. The health outcome with the highest prevalence was hay fever (occurring in the previous 6 months) with 31.7%. The use of non-electric heating sources, parental smoking and mould in the house were risk factors of most concern for respiratory health. During bivariate analysis mould was found to be associated with a number of health outcomes, most notably having bronchitis, with a crude OR of 4.74. An adjusted odds ratio of 4.05 was found for smoking in the house and having bronchitis. An adjusted OR of 6.32 was found for using gas or paraffin and having episodes of wheezing. These results may be used to direct future research studies as well as assist air quality management practices in the area. Finally, a technique to handle contradictions in questionnaire responses was developed to maximise use of data collected for application in under-resourced research environments. Copyright 2011, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Albers, PN 2011, Baseline assessment of child respiratory health in the Highveld Priority Area, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-02172012-162359 / > C12/4/230/gm / Dissertation (MSc)--University of Pretoria, 2011. / School of Health Systems and Public Health (SHSPH) / Unrestricted

Amid a growing world population and diminishing living space, the discerning and beneficial use of steel plant slag as liming material in agriculture has become a viable option. However, until the potentially detrimental effect on human health and environmental quality of heavy metals contained within the matrixes of slag has been assessed, the use of slag in agriculture cannot be deemed sustainable. This study aims to correlate the mechanisms by which chromium(III) and nickel are sorbed in Eastern Highveld soils to easily classifiable soil constituents. In addition, the influence of an external source of silicon, as would be the case in dissolving slag, on Cr(III) and Ni mobility was investigated. The study consisted of an investigation into the mechanisms by which Cr(III) and Ni are sequestered in soil within a single wetting and drying cycle, as well as over a period of five rewetting and drying cycles. The effect of Si was observed for the latter and a detailed mineralogical study conducted as part of the former. Additionally, the reactivity of and heavy metal (Cr and Ni) release from two commercially available slag samples used as liming material in a highly buffered soil was investigated. Five main conclusions were drawn: (i) whereas Cr(III) is effectively sorbed (even at near water saturated conditions) and precipitation ascribed to bulk-solution saturation, Ni is not sequestered as effectively, and initially precipitates owing to the influence of soil mineralogy; (ii) conclusive evidence could not be gathered for the further immobilisation after sorption of Cr(III) and Ni over a short time period; (iii) both Cr(III) and Ni associate mainly with the amorphous Fe oxide mineral phase; (iv) an external source of Si renders Ni less mobile in soil that does not sequester the element effectively, but more mobile in soil that does tend to sequester the element to some degree; and (v) although neither Cr(III) nor Ni mobility could be explained using field classifiable soil characteristics (soil colour and texture), soil mineralogical and detailed surface charge characterisation did provide explanations for sorption behaviour. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Plant Production and Soil Science / unrestricted

Evaluation determines the impact of social services as well as job performance and assures communities that social workers render effective services. Post audits are done as part of performance management at the Christian Social Councils in the Highveld Synodal Region. The purpose of this research is to look at the experiences of social workers that had a post audit to determine whether adjustments to improve the audit system are needed. A qualitative approach with an exploratory, descriptive and contextual research design was followed. Participants were identified according to the purposive sampling method. Data was collected during semi-structured interviews. The data was analysed and verified according to the models of Tesch (in Creswell, 2003) and Guba (in Krefting, 1991), respectively, and processed in the research report. / Social Work / M. A. (Social Science)

Evaluation determines the impact of social services as well as job performance and assures communities that social workers render effective services. Post audits are done as part of performance management at the Christian Social Councils in the Highveld Synodal Region. The purpose of this research is to look at the experiences of social workers that had a post audit to determine whether adjustments to improve the audit system are needed. A qualitative approach with an exploratory, descriptive and contextual research design was followed. Participants were identified according to the purposive sampling method. Data was collected during semi-structured interviews. The data was analysed and verified according to the models of Tesch (in Creswell, 2003) and Guba (in Krefting, 1991), respectively, and processed in the research report. / Social Work / M. A. (Social Science)

In spite of the relative simple vegetation structure, the Grassland biome has surprisingly high species diversity. The Grassland biome is also the most transformed biome in South Africa, with cultivation having the largest impact. When croplands are abandoned, secondary succession leads to low diversity Hyparrhenia hirta dominated grassland. A combination of two seed mixtures, two seeding densities and two establishment methods was established in plots on a recently abandoned cropland at Suikerbosrand Nature Reserve to evaluate their effect on secondary succession. The rip plots, where more resources were available between the rip lines, have shown higher densities of relic weeds as well as local perennials, showing some progressive successional movement. However, Hyparrhenia hirta was one of the non-sown perennials increasing in the rip plots. Hyparrhenia invasion and relic weeds were best controlled in the plough plots. Although Hyparrhenia was successfully controlled in plough plots, no secondary succession occurred in these treatments. / Agriculture, Animal Health & Human Ecology / M. Tech. (Nature Conservation)

In spite of the relative simple vegetation structure, the Grassland biome has surprisingly high species diversity. The Grassland biome is also the most transformed biome in South Africa, with cultivation having the largest impact. When croplands are abandoned, secondary succession leads to low diversity Hyparrhenia hirta dominated grassland. A combination of two seed mixtures, two seeding densities and two establishment methods was established in plots on a recently abandoned cropland at Suikerbosrand Nature Reserve to evaluate their effect on secondary succession. The rip plots, where more resources were available between the rip lines, have shown higher densities of relic weeds as well as local perennials, showing some progressive successional movement. However, Hyparrhenia hirta was one of the non-sown perennials increasing in the rip plots. Hyparrhenia invasion and relic weeds were best controlled in the plough plots. Although Hyparrhenia was successfully controlled in plough plots, no secondary succession occurred in these treatments. / Agriculture, Animal Health and Human Ecology / M. Tech. (Nature Conservation)

The objectives of the study were to identify, classify, describe and map the plant communities in the proposed Highveld National Park, including the degraded Spitskop areas. Vegetation sampling was done by means of the Braun-Blanquet method and a total of 108 stratified random relevés were sampled. A numerical classification technique (TWINSPAN) was used and the result was refined by Braun-Blanquet procedures. The final results of the classification procedure were presented in the form of phytosociological tables and twelve plant communities were described. For indirect ordination, a Detrended Correspondence Analysis (DCA) algorithm was applied to the data set to confirm the phytosociological association and to assess floristic relations between communities. For direct environmental gradient analysis the Canonical Correspondence Analysis (CCA) was applied to the data using the CANOCO software program. The plant communities were combined into six management units based on similarities regarding vegetation composition, habitat, topography and soil characteristics. Characterization of land degradation was done by grouping erosion into different classes and different degrees of severity. Degraded areas in need of rehabilitation and restoration were identified and described. Recommendations were made with regard to rehabilitation and monitoring of all degraded areas in the HNP. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2008.

The objectives of the study were to identify, classify, describe and map the plant communities in the proposed Highveld National Park, including the degraded Spitskop areas. Vegetation sampling was done by means of the Braun-Blanquet method and a total of 108 stratified random relevés were sampled. A numerical classification technique (TWINSPAN) was used and the result was refined by Braun-Blanquet procedures. The final results of the classification procedure were presented in the form of phytosociological tables and twelve plant communities were described. For indirect ordination, a Detrended Correspondence Analysis (DCA) algorithm was applied to the data set to confirm the phytosociological association and to assess floristic relations between communities. For direct environmental gradient analysis the Canonical Correspondence Analysis (CCA) was applied to the data using the CANOCO software program. The plant communities were combined into six management units based on similarities regarding vegetation composition, habitat, topography and soil characteristics. Characterization of land degradation was done by grouping erosion into different classes and different degrees of severity. Degraded areas in need of rehabilitation and restoration were identified and described. Recommendations were made with regard to rehabilitation and monitoring of all degraded areas in the HNP. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2008.