In areas of transported overburden there is frequently a weak relationship between soil and the underlying mineralized bedrock. Vegetation has the capability to absorb metals from the underlying substrate via its extensive root systems. These metals are translocated to the various organs of the plant such as leaves, twigs bark and roots without negatively impacting on the normal functioning of the plant. The analysis of the vegetation may therefore be used to locate deeply buried mineral targets. The main focus of this investigation was to determine the suitability of A. karroo and B. albitrunca for biogeochemical prospecting for gold in the Blue Dot Mine area. The appraisal of the suitability for both plant species requires an understanding of element absorption and distribution patterns in relation to variable composition of bedrock and associated underlying gold mineralization.

In areas of transported overburden there is frequently a weak relationship between soil and the underlying mineralized bedrock. Vegetation has the capability to absorb metals from the underlying substrate via its extensive root systems. These metals are translocated to the various organs of the plant such as leaves, twigs bark and roots without negatively impacting on the normal functioning of the plant. The analysis of the vegetation may therefore be used to locate deeply buried mineral targets. The main focus of this investigation was to determine the suitability of A. karroo and B. albitrunca for biogeochemical prospecting for gold in the Blue Dot Mine area. The appraisal of the suitability for both plant species requires an understanding of element absorption and distribution patterns in relation to variable composition of bedrock and associated underlying gold mineralization.

Please read the abstract in the section, 00front of this document / Dissertation (M Inst Agrar (Land-Use Planning))--University of Pretoria, 2008. / Agricultural Economics, Extension and Rural Development / MInst Agrar / Unrestricted

Magister Scientiae - MSc / In areas of transported overburden there is frequently a weak relationship between soil and the underlying mineralized bedrock. Vegetation has the capability to absorb metals from the underlying substrate via its extensive root systems. These metals are translocated to the various organs of the plant such as leaves, twigs bark and roots without negatively impacting on the normal functioning of the plant. The analysis of the vegetation may therefore be used to locate deeply buried mineral targets. The main focus of this investigation was to determine the suitability of A. karroo and B. albitrunca for biogeochemical prospecting for gold in the Blue Dot Mine area. The appraisal of the suitability for both plant species requires an understanding of element absorption and distribution patterns in relation to variable composition of bedrock and associated underlying gold mineralization. / South Africa

Plant nutrient management plays a vital role in the success or failure of modern Lucerne production. In South Africa, Lucerne is produced under a wide range of climatic conditions, under dryland and irrigation and in some areas throughout the year. This means that there is a continuous demand for nutrients under a wide range of environmental conditions. The most important factors affecting the nutrient requirement of Lucerne is yield, the cutting schedule, climate and management practices. To enable site-specific crop requirements, the spatial variation of soil and plant properties within a field can be managed with the use of geostatistical techniques. Some work has also been done to evaluate the use of geostatistics in the design of agricultural field experiments to provide better field characterization and improve plot layout. The aim of this study was to compare plant yield and composition with soil properties using both classical and geostatistical techniques. The study was conducted from June 2001 to February 2002 on an 18ha Lucerne stand in the Brits district in the North West Province. A rectangular area of 160m X140m was demarcated as the study area and comprised of two soil units (Hutton and Shortlands forms). Seventy-two sampling points (nodes) were laid out on a 20m square grid, with an additional 90 sampling points laid out on a 2.5m square grid at six randomly selected node points. Soil (0-300 mm) and plant samples were taken within a 0.6m square at each of the sampling points for chemical analysis. Starting in June 2001, yield sampling was done on six occasions, at approximate intervals of 5 weeks. A randomized complete block design trail layout was superimposed on the geostatistical grid design and consisted of seven pseudo treatments, replicated four times. Basic statistical analysis were performed and spatial presentations of the variation of the plant and soil properties and Lucerne yield were made using geostatistical analyses. Analyses of variance were used to test for differences between pseudo treatments for all plant and soil properties. The two soils on the stud site, exhibited differences in certain properties, which caused a bi-modal population in the data. Poor correlations were found between plant nutrient uptake and soil properties as well as yield, with little or no resemblance when comparing their spatial distribution. This emphasizes the fact that the uptake of elements is not solely dependant on the concentrations thereof in the soil solution, but on other factors. Temporal variations in Lucerne yield were also observed. Although there were large differences in spatial variation of Lucerne yields across harvesting events, similar spatial patterns were evident. From an analysis of variance of the RCB design it was concluded that the experimental field was homogeneous enough to lay out a standard block design experiment. However, scrutiny of the structure of spatial variability of pH(H2O) revealed that the standard RCB designs did not provide homogeneous blocks with respect to soil variability. The consequent redesign of the experiment whereby all plots were randomly allocated to treatments and replications, led to dramatically different results: significant differences were obtained for plant and soil properties as a function of the pseudo treatments. From this study it is clear that spatial variability of soil and plant properties can jeopardize the results of a standard block design field experiment and it is therefore recommended that the layout of field experiments should be designed to the cognizance of the spatial variation of a soil property that correlated highly with a chosen response variate. / Dissertation (MSc (Soil Science))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted

Several hundred chemical analyses of early Proterozoic lavas of the Witwatersrand triad (incorporating the Dominion Group, Witwatersrand Supergroup and Ventersdorp Supergroup) in the Klerksdorp area, have revealed the presence of various distinct magma types. These essentially correspond to formally defined lithostratigraphic units, but several inconsistencies have necessitated the use of informal nomenclature. The lavas have been regionally metamorphosed to low-grade, greenschist facies assemblages. Original igneous textures are preserved, despite a metamorphic overprint. Metamorphism has resulted in a certain degree of random chemical remobilization. Ba, Sr, Rb, K₂0, Na₂0 and CaO have been highly mobile, and their usefulness in petrogenetic modelling is extremely limited. In contrast, Zr, Nb, Y, LREE's, Cr, Ni, Ti0₂ P₂0₅ and Al₂0₃ have remained immobile. Ti/Zr and Ti/P ratios together constitute efficient discriminating variables for characterizing the different magma types. Lava compositions range from primitive Mg-rich tholeiites to rhyolites, the bulk being tholeiitic andesites. Al₂0₃ contents do not exceed 15%, a feature which reflects the tholeiitic, as opposed to calcalkaline, character of these lavas. Two magma-types are present within the Dominion Group, which is a typical example of bimodal volcanism. The Dominion basic lavas are overlain by the Dominion acid porphyries, with a limited amount of interfingering. The basic lava suite is highly fractionated, with compositions ranging from Mg-, Cr- and Ni-rich tholeiites (close to primary mantle melts) to evolved tholeiitic andesites. The most primitive liquids evolved by 45% fractional crystallization of hornblende, followed by a further 70% crystallization of an orthopyroxene-plagioclase assemblage containing up to 3% sulphides. The Dominion porphyries are rhyolitic, display very limited compositional variation, and probably represent a crustal melt related to the same magmatic event which produced the basic lavas. The only lavas from the Witwatersrand Supergroup present in the Klerksdorp area are those of the Crown Formation (Jeppestown amygdaloid). These are tholeiitic dacites which display extremely limited compositional variation, and are unrelated to any of the other magmas of the Witwatersrand triad. The Ventersdorp Supergroup comprises 4 magma-types: The Kliprivierberg Group lavas at the base are subdivisible into 3 sub-types on the basis of Zr contents. (Zr>11Oppm) are the most evolved. They are tholeiitic andesites which display fairly limited compositional variation. It is likely that more evolved compositions are present in other areas where the porphyritic lavas which characterize this unit are better developed. The overlying Orkney lavas are characterized by 110ppm>Zr>90ppm. They are tholeiitic andesites of similar composition to the Alberton lavas, but have lower incompatible element levels, higher siderophile element levels, and are of extremely uniform composition. The uppermost Loraine/Edenville lavas range from magnesian tholeiites to tholeiitic andesites. They are distinguished by Zr< 90ppm, and contain the most primitive magmas af the Witwatersrand triad, with up to 17,5% MgO, 2600ppm Cr, 600ppm Ni and M-values up to 77. The most primitive liquids evolved by 38% fractional crystallization of orthopyroxene ∓ chromite, followed by 35% fractional crystallization of an extract containing clinopyroxene and plagioclase. The absence of olivine precipitation is a result of the inherently high Si0₂ content of the magma. The Loraine/Edenville, Orkney and Alberton lavas do not lie on a common liquid line of descent, but are probably consanguinous. The Platberg Group overlies the Kliprivierberg Group, and has a coarse-clastic sedimentary unit, the Kameeldoorns Formation, at the base. Three petrographically distinct porphyritic lava sequences overlie the Kameeldoorns Formation, namely the informal "Goedgenoeg formation", the Makwassie quartz-feldspar porphyries and the Rietgat Formation. Despite petrographic differences, the Goedgenoeg and Rietgat lavas are chemically indistinguishable and thus form a single magma-type. The Makwassie porphyries are dacitic in composition with a high proportion of feldspar and quartz phenocrysts. Rational variation trends are attributed to a nett loss of Si0₂ during secondary alteration. The porphyries are probably of crustal origin. The Goedgenoeg/Rietgat lavas display unusual chemistry and a broad, irrational compositional spectrum. They contain very high incompatible element levels, high nonnative quartz, as well as high MgO, M-values, Cr and Ni relative to the other tholeiitic andesites of the Witwatersrand triad. It is tentatively suggested that they are hybrid magmas containing both crust and mantle components, the former possibly represented by the Makwassie porphyries. Field evidence suggests that Platberg volcanism commenced directly after Klipriviersberg volcanism ceased, and was accompanied by a period of enhanced tectonic activity. The Platberg lavas thus probably reflect a crustal melting cycle associated with the Klipriviersberg magmatic event. The Allanridge lavas are the youngest rocks of the Witwatersrand triad. They are separated from the Platberg Group by a unit of flat-lying sediments, the Bothaville Formation, which was deposited after an extended period of peneplanation. The Allanridge lavas form a separate magma-type. They are tholeiitic andesites of similar composition to the Alberton lavas, but have higher incompatible element levels and are not consanguinous. The compositional similarities amongst the basic magma-types of the Witwatersrand triad suggests that all were generated in an hydrous mantle. Interelement ratio differences between the various magma-types nevertheless support the concept that the mantle was chemically heterogeneous during the early Proterozoic.

Thesis (M. Tech.) -- Central University of Technology, Free State, 2008 / In this study, the development and implementation of a quality-monitoring program for raw milk as part of the quality management system of a milk processor was studied. Various aspects that contribute to raw milk quality were also included. Ten factors that are important in the production of good quality raw milk were summarised in the Ten Point Plan for the production of quality raw milk. Thirty-eight producers, who have supplied raw milk to the processor over a period of five year, were involved in this program. The producers are located all over the Northwest Province. Sixty thousand litres of milk is processed at the processor daily. The milk is taken in from the farms on alternative days by tankers supplied by the processor. A mark sheet was developed to evaluate control points during milking that can be measured directly from the laboratory. This was done monthly. Factors that could not be measured in the laboratory were evaluated when visits to the milk parlours were done twice a year. At the end of the year, the results of the mark sheet as well as the results of the parlour audits were compiled on a quality chart and the results were calculated as a percentage. The processor used the results of the quality charts to reward producers for quality milk. It was found that producers do not have the necessary infrastructure and knowledge to analyse milk. Analysing the raw milk and releasing the results to the producer are important measures to identify and manage problem areas that can pose a risk to the production of good quality raw milk. It is very important to supply the producer with the correct and relevant information because most of the representatives of companies, which visit the farms, supply information to the benefit of the product they sell. A formal monitoring program ensures that raw milk adhere to quality measures due to the fact that producers know the basic principles necessary for the production of good quality raw milk and the fact that the producer can implement measures in his/her own unique farm environment. The implementation of the Ten Point Plan for the production of quality raw milk at the processor had a significant influence on the quality of raw milk that was bought from producers. During times of milk shortages, the processor had to buy milk from alternative sources, which have no quality-monitoring program. Most of the times, this milk did not comply with the law regarding the total bacterial count, the coliform count, and the E. coli count. Record keeping is an important part of the management system of a dairy. Results from this study stressed a meaningful relationship between the keeping of records as mentioned in the Ten Point Plan and the production of good quality raw milk. It is recommended that producers be sharpened regarding the requirements for the production of good quality raw milk. Purchasing good quality raw milk assured the marketing of the best quality dairy products to the consumer. The contribution of this study to the dairy industry is the fact that the implementation of a quality-monitoring program ensures the maintenance of a sustainable quality of raw milk to the industry.

Thesis (M. Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2020 / Food security is a broad concept especially as far as rural food security in countries is concerned. In essence, it is a phenomenon with the goal of ensuring that all individuals have at all times, an adequate level of food and which they will be able to utilize to meet their increasing consumption demand. Studies have shown that like other countries, South Africa is food secure at the national level but very food insecure at the household level. It is also shown that food insecurity is not fuelled by a lack of food but a lack of food insecurity tackling strategies. The aim of the study is to examine the determinants of food security among rural households in Magong, North West Province, South Africa where the main prevalent economic activity is farming supported with other formal and informal types of employment. A multi-stage sampling technique was used to select the respondents that were interviewed. The first stage involved selecting districts and the second stage was the selection of municipalities. Farm and non-farming households were selected. Structured questionnaire were administered to 108 households. The third stage involved a selection Magong village using purposive sampling based on high concentration of both farming and non-farming activities were selected, which in our case is Magong. The fourth stage involved the selection of respondents based on simple random sampling proportionate to size. The study employed logit model for as data analysis. Of the variables modelled, only income and land size had a significant influence on food security. As far as age is concerned, it was evident that the youth participation in agriculture lacks. This is because most young people are still after white collar jobs. Some were still in the academic world awaiting their certificates which they hope to use a ticket to their first job. The participation in agriculture increases steadily between ages 31 and 50 which could be because the persons in this age brackets were looking for ways to store their wealth as they approach their retirement age. Some of the respondents have inherited the farms from family members and are therefore “forced” to keep the family business running for the sake of sustainability. With regards to the marital status, there is a high number of single/ never married respondents compared to the other groups. This could be people co-habiting and choosing not to marry as a result of the economic conditions making marriage costs unaffordable. Divorce was at its lowest amongst the respondents.v In terms of the gender of the respondents, there was a high participation of women in agriculture. This may be a result of women-based agricultural programmes implemented in the past in the study area. All the variables had a positive relationship with food security. Age had a positive effect of food security, with a positive parameter (β=0.013) which indicated that contrary to what other researchers found, an increase in age when all other factors are held constant, resulted in an increase in food security. The marital status of the household head also positively affected food security. This indicated that compared to their unmarried counterparts, married household heads were food secure (β=0.049). The findings also indicated that married couples and people living with partner had a higher chance of being food secure than those who were single, divorced or widowed. According to the results, male headship of households increases food security by 0.398. It was found that the larger the household size, the more food secure it is. This may be because as the number of members in the household increase, they find more ways of making money and combating food insecurity. A unit increase in household size increases food security by .093 while an increase in land size, increases food security by 0.394. This is expected because as the land size increases, there are chances that the productivity will also increase. From the results of the survey household income had a positive effect on food security. Income is very important as it determines the household’s affordability and its ability to meet its needs

In this Thesis, from the disciplinary vantage point of English Studies, I explore some of the complex meanings that may be attributed to several forms and practices of South African consumer culture: magazines, malls and themed leisure. While these contemporary cultural 'texts' are often ephemeral, and people's attachments to them fractured, transient or at least ambivalent rather than unproblematic, my argument takes issue with the pessimism that informs much local and international criticism of consumer culture. My Thesis turns to concepts of affect, image, sign and discourse which have become features of current English Studies in order to generate readings of commercial culture more nuanced than the 'hard analyses' favoured by dominant practitioners of 'radical' South African cultural studies. At the same time, though, my analyses have learnt through disparate forms of local cultural study the necessity of grounding textuality in the structures of political economy. By means of manageable yet conceptually-suggestive South African instances, I consider how commodities and commodified experiences - generated in the first instance by the vested interests of Capital and related ideologies - may nevertheless be experienced by people in a plethora of ways not directly tied to the commercially-expedient construct of the 'target audience'. This experiential process entails a rampant volatility typical of a mass-mediated lexicon which challenges boundaries between high and low, formal and unofficial, propriety and the improper. While advertising and promotion, for instance, function as corporate attempts to contain proliferating signifiers and to secure a preferred, 'authorised' meaning for cultural goods or services, it is also the case that consumers themselves, perhaps creatively and certainly in clandestine ways that escape the supposed authorities of either market researcher or academic intelligence, author meanings that rework the limitations of what still tends to be construed within the university as a culture industry at once banal and insidious. The meanings of the contemporary cultures with which I deal, then, are highly mediated and many-layered, rather than constituting the mere surface announcement often imagined by scholars of both literary culture and of media- and cultural studies. The contexts of my Thesis are particular: it was completed in 1998, and has been produced from a university in KwaZulu-Natal by an academic formally trained in English Studies. In some respects, then, the interpretations I offer are narrow: geographically, historically and disciplinarily focussed. Yet in working on South African examples of commoditised forms and practices that derive from metropolitan vectors and have convoluted international genealogies, I have also sought to theorise the shifting interrelations of regional and national, local and global, discipline-specific and interdisciplinary knowledge. Drawing widely on studies into consumer relations - and at apposite points identifying conceptual connections and differences between 'foreign' figures like Michel de Certeau and influential South African thinkers such as Njabulo S. Ndebele - I suggest that for all its shortcomings consumerism needs to be understood as active process rather than as passive effect. My argument implies that such a rethinking of the conventional binaries of production and consumption is appropriate in a South Africa which is gradually giving substance to a democratic social order. Even within a politics premised on the individual, forms of consumption such as magazine reading and shopping need not necessarily be scorned as the selfish, even hedonistic pursuits caricatured by ideological purists: the Thesis seeks to demonstrate that people are at once citizens and consumers, individuals searching after distinctive identity and style as well as desirous of achieving a variety of community inflected bonds. Overall, the commercial culture examined in the Thesis is represented not as inevitably marred by cultural deficiency and degraded value - despite the dissatisfactions, irritations and deferred pleasures which for many of us form at least one facet of consumption - but as an everyday spectacle which is available for symbolic interpretation and aesthetic investment. This investment may be emotional as well as cognitive, sensuous as well as critical, mundane as well as exceptional, since individuals come to commodity culture with a range of longings, dreams, fears and sedimented allegiances. As my readings demonstrate, it is such diversity of response - provisional and elusive rather than predictable and guaranteed - which gives the lie to theories which are 'always-already' premised on the prior inscription and encoding of consumerism as manipulation. / Thesis (Ph.D.)-University of Natal, Durban, 1998.