List of Titles

A study of the population dynamics, production and potential yield of the sardine Limnothrissa Miodon (Boulenger) in Lake Kariba

- Marshall, Brian Eric

Authors: Marshall, Brian Eric
Date: 1987
Subjects: Fishes Lake Tanganyika sardine
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5191 , http://hdl.handle.net/10962/d1001967
Description: The limnology of Lake Kariba, especially those aspects that affect sardine biology, are described. The hydrological regime of the lake is seen as a major influence and may be one of the reasons why the fish are very much smaller in Kariba than they are in Lakes Tanganyika or Kivu. Growth was reassessed and there appeared to be a correlation between rates of growth and limnological parameters. In particular, the fish appeared to grow faster, but smaller, in the man-made lakes and this may be a consequence of food shortages brought about by their hydrological characteristics. Mortality rates were also much higher in Kariba and this tended to support the view that the lake is a relatively unsuitable habitat for the sardines. However, estimates of biomass, expressed in terms of lake volume, contradicted this as they were very similar in both Kariba and Tanganyika. The life history strategy of Limnothrissa in Kariba was therefore to reduce its size and increase its productivity in order to maintain the maximum possible biomass and its very high P/B̄ ratio was probably the means by which this was achieved. In terms of lake volume the predicted yields from the pelagic communities of Kariba and Tanganyika were very similar, equivalent to about 20 000 t annually for Kariba. This is close to the yield predicted by several empirical models and the fishery now appears to be entering a phase where increases in effort will not be matched by increased yields. The mechanisms for controlling effort in the fishery appear to be inadequate and particular concern was expressed about the lack of co-ordination between the Zimbabwean and Zambian fishery authorities in planning the development of this shared resource.
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Date Issued: 1987

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Gold metallogeny of Australia

- Rankine, Graham M

Authors: Rankine, Graham M
Date: 1987
Subjects: Gold ores -- Geology -- Australia , Gold mines and mining -- Australia , Gold -- Metallurgy -- Australia
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4928 , http://hdl.handle.net/10962/d1004676
Description: The gold metallogeny of Australia is predominantly confined to the Archaean and Palaeozoic Provinces. The Archaean gold occurrences are predominantly hosted in ultramafic-mafic dominated greenstone belts, with less associated tofelsic-volcanic and sedimentary sequences. Most gold occurrences are confined to shear zones or faults, and adjacent discoveries of economic laterite-hosted deposits, host rocks. Recent are presently under investigation and will supply a significant proportion of production in the future. The Proterozoic gold deposits of Australia , are confined to geosyncinal sequences, commonly turbidites (eg: Telfer), with other hydrothermal deposits associated directly to granites. An important feature of the North Australian Craton deposits, is the spatial association of most deposits to granite bodies, although a genetic link has not been established conclusively. The Roxby Downs deposit in South Australia is a unique occurrence of gold in association to copper, uranium and R.E.E. This deposit is tentatively related to intraplate alkaline-magmatism, with further work necessary. The most significant recent discovery of gold mineralization in Australia is in the Drummond Basin in Queensland. This epithermal is tentatively related to mineralization within the Georgetown Inlier. The latter mineralization is Permo-Carboniferous, in a Proterozoic (and possibly Archaean) sequence of schists. It is tentatively suggested that all the gold mineralization in northern Queensland may be related to single tectonic event, a feature which requires further study . Other mineralization in the Phanerozoic includes the turbidite-hosted metamorphogenic deposits of Victoria, the rift related deposits in New South Wales and magmatic related deposits in Queensland. The gold deposits in Australia may in the future be classified in a tectonogeological framework, similiar to the layout of this dissertation, particularly once further data becomes available on recent discoveries.
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Date Issued: 1987

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A comparison of nesting behaviour and prey selection in some Southern African species of Ammophila (Hymenoptera : Sphecidae)

- Weaving, Alan James Shelley

Authors: Weaving, Alan James Shelley
Date: 1987
Subjects: Hymenoptera
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5600 , http://hdl.handle.net/10962/d1002050
Description: Nesting behaviour and prey selection was compared in eight species of Ammophila. The frequent sympatry of these species was a central point of interest in the study. Nest siting differed markedly in several species. A. ferrugineipes, A. dolichodera, A. dolichocephala and, probably, A. conifera nested mostly in open habitats, this being regarded as the most common situation for the majority of Ammophila. A. beniniensis was unusual in nesting in well vegetated habitats, A. vulcania doing so amongst small clumps of vegetation in otherwise open habitats. A. insignis nested in vertical banks or old animal burrows and A. braunsi utilised abandoned burrows of other wasps situated in non-friable clay soils. This is the first time such nest siting has been reported for Ammophila and each of these two species is consequently unique. Many aspects of nest construction behaviour, in particular methods of soil waste disposal, sealing of nests and their final coverage, differed interspecifically, in some cases intraspecifically, but often apparently in response to the habitat. With regard to nest provisioning strategies, all species hunted after digging their nests, except A. dolichodera which is the first Afrotropical Ammophila reported to hunt before excavating its nest. This brings the total number of the world's species of Ammophila showing this behaviour to three. This species, A. beniniensis, A. braunsi and A. vulcania provided one caterpillar per nest; the others supplied several, A. insignis being the only mass provisioner. A. ferrugineipes showed a form of progressive provisioning and maintained several nests at a time; it is the only Afrotropical species known so far to do so. Only two extra-limital species have been reported showing similar behaviour. The observed variations in provisioning strategies can most easily be explained in relation to the habitat. Investigation of prey selection showed that there was very little interspecific overlap in the species of caterpillars used for provisioning nests. This was shown to be due mainly to differing hunting habitat preferences. The various overall patterns of nesting behaviour, and variations in the different components within these patterns, were considered most likely to have resulted from allopatric speciation in different types of vegetation, the more advanced patterns arising in open habitats. The frequent occurrence of sympatry appears to be a reflection of a shifting distribution of mosaic patterns of vegetation types and the post-speciation spread of species. This influence of habitat on behaviour and prey selection has emphasised the need for caution in drawing phylogenetic conclusions from ethology. Further, these considerations provide an alternative to competition in attempting to explain the observed behaviour patterns and distribution of these wasps.
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Date Issued: 1987

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COSATU constitution as amended at COSATU 2nd National Congress l987

- COSATU

Authors: COSATU
Date: 1987
Subjects: COSATU
Language: English
Type: text
Identifier: http://hdl.handle.net/10962/109708 , vital:33182
Description: We the Trade Union representatives here present firmiy commit ourselves to a unified democratic South Africa, free of oppression and economic exploitation. We believe that this can only be achieved under the leadership of a united working class. Our history has taught us that to achieve this goal we will have to carry out the following tasks. To organise the unorganised workers and build effective trade unions based on the democratic organisation of workers in the factories, mines, shops, farms and other workplaces. Organise national industrial trade unions, financed and controlled by their worker members through democratically elected committees. Unify these industrial unions into a national worker controlled federation. Combat the divisions amongst the workers of South Africa and unite them into a strong and confident working class. Encourage democratic worker organisation and leadership in all spheres of our society together with other progressive sectors of the community. Reinforce and encourage progressive international worker contact and solidarity so as to assist one another in our struggles.We call on all those who identify with this commitment to join us and the workers whom we represent as comrades in the struggle ahead. We call on all trade unions to strive to unite their members in their ranks without discrimination and prejudice, and therefore resolve that this federation shall determinedly seek to further and protect the interests of all workers and that its guiding motto shall be the universal slogan of working class solidarity: "AN INJURY TO ONE IS AN INJURY TO ALL".
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Date Issued: 1987

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A study of the nature, function and availability of orders of restitutio in integrum and specific performance as remedies in South African law

- Lambiris, Michael A

Authors: Lambiris, Michael A
Date: 1987
Subjects: Restitutio in integrum (Roman law) Restitutio in integrum -- South Africa Remedies (Law) -- South Africa
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3703 , http://hdl.handle.net/10962/d1004752
Description: This study is of two remedies that are available in South African law: orders of restitutio in integrum, and specific performance. The study demonstrates that, by treating these remedies as legal topics in their own right, a greater understanding emerges of their inherent characteristics, the role that they play in the law, and of the particular circumstances in which these remedies are available. An order of restitutio in integrum performs an important and unique function in South African law. The fundamental realisation is that it is a remedy in terms of which the courts exercise an extraordinary and discretionary power, and nullify ab initio legal transactions, or the legal consequences of events, which were previously perfectly valid and enforceable at law. Because of the extraordinary nature of this remedy, the circumstances in which it is available are limited by the requirement that iusta causa must exist to justify nullification. Further, before the remedy is available, the person seeking relief must have suffered loss or prejudice as a result of the event complained of. Finally, a mutual restoration of benefits received by the persons involved is required. The nature and effect of orders of restitutio in integrum, and the essential elements which determine the availability of the remedy, enable it to be distinguished from, and contrasted with, other remedies in South African law. An order of specific performance is available in South African law, at the option of a plaintiff, to enforce the actual performance of contractual undertakings. The remedy is appropriate to enforce positive undertakings, as well as acts of restraint. For the remedy to be available, it is firstly necessary that a contractual obligation be proved to exist. Secondly, performance of that obligation must be due. Thirdly, the performance sought must not in fact have already been rendered. These elements determine the availability of the remedy in particular factual circumstances, such as in cases involving pre-emptive rights. The nature and characteristics of the remedy are determined by principles of South African, and not English law. The remedy is available as of right in South African law, but subject to a discretionary power of a court to refuse to order specific performance. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
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Date Issued: 1987

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A revision of the genus Rafnia thunb.(fam. Fabaceae : sub. fam. Papilionoideae)

- Richardson, Gaynor Rose-Marie

Authors: Richardson, Gaynor Rose-Marie
Date: 1987
Subjects: Thunbergia -- Classification
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4237 , http://hdl.handle.net/10962/d1004746 , Thunbergia -- Classification
Description: A taxonomic revision of Rafnia Thunb. (Fam. Fabaceae, Subfam . Papili onoideae) is presented in which 21 species are recognised. The relative value of the taxonomic characters is discussed. An electron microscopy study of the seed surface, pollen grains and several sexual characters has been undertaken. Two keys are included , one using vegetative and floral characters and the other using ultrastructure of the testa. Each species description is accompanied by illustrations and a distribution map. Historical and ecological notes on the genus are given
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Date Issued: 1987

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The effects of relative speed on selected physiological, kinematic and psychological responses at walk-to-run and run-to-walk interfaces.

- Candler, Paul David

Authors: Candler, Paul David
Date: 1987
Subjects: Walking -- Physiological aspects , Running -- Physiological aspects
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5164 , http://hdl.handle.net/10962/d1016081
Description: [Conclusions] l) The two forms of human locomotion, walking and running, are distinctly different and in evaluating these gait patterns consideration must be given to this fact. 2) The impression created by the energy cost curves, that there is a single locomotor interface for both walking and running is a false one . There are two distinctly different locomotor interfaces, the walk-to-run interface and the run-to-walk interface. The former appears to correspond with the "metabolic intersection point" and therefore has some metabolic significance. The latter appears to be merely an "overshoot" of the walk-to-run interface and presently has no apparent metabolic significance. 3) Because the walk-to-run interface speed corresponds with the intersection point of the energy cost curves, physiological responses to walking and running at this speed do not differ significantly. However, cadence and stride length patterns for these two locomotor patterns are distinctly different at this point. 4) The identification of single physiological or kinematic factors during perceptions of exertion in any given situation is an extremely difficult if not impossible task. Perceived exertion should therefore be considered a multi-factorial concept and should be evaluated as such. 5) The use of relative speed as a technique for reducing inter-subject variability in physiological and kinematic factors is worthless unless diverse ranges in morphological linearity are a characteristic of one's subject pool
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Date Issued: 1987

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Die dood, die minnaar en die oedipale struktuur in die Ingrid Jonker-teks

- Van Wyk, André Johan

Authors: Van Wyk, André Johan
Date: 1987
Subjects: Jonker, Ingrid, 1933-1965 -- Criticism and interpretation Afrikaans poetry -- History and criticism
Language: Afrikaans
Type: Thesis , Doctoral , PhD
Identifier: vital:3608 , http://hdl.handle.net/10962/d1003917
Description: From Inleiding: In dié inleiding word die implikasies van die woord "teks", asook die resepsie van die Ingrid Jonker-teks in die lig van haar dood, en 'n eie benaderingswyse, in teenstelling met die tradisionele kritiese metodes, bespreek. 1.1 Die teks: Die Ingrid Jonker-teks behels (met die dood, die rninnaar en die OedipaIe struktuur as uitgangspunt) aIIes waarop die woorde "Ingrid Jonker", as teks - die parentese tussen die datums op haar grafsteen - dui. Dit beteken dat genre-onderskeidinge en die onderskeid biografie en literatuur opgehef word. Verdere implikasies van die woord "teks" gaan vervolgens ter inleiding ondersoek word. Daar sal ruim gebruik gemaak word van die literêr-teoretiese en filosofiese veronderstellinge van Julia Kristeva, Maurice Blanchot, Jacques Derrida, Jacques Lacan, Pierre Macherey en Roland Barthes.
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Date Issued: 1987

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Aspects of brutality : anxious concepts in sculpture since 1950

- Lang, Graham Charles

Authors: Lang, Graham Charles
Date: 1987
Subjects: Sculpture, Modern -- 20th century Violence in art
Language: English
Type: Thesis , Masters , MFA
Identifier: vital:2484 , http://hdl.handle.net/10962/d1012724
Description: It would be wrong to suggest that this essay is in any way a comprehensive study of brutal sculpture. Certainly not. There have been many deliberate omissions for reasons which become clear in the text. Very briefly, omissions of certain sculptors and their work are largely due to my wish to avoid repetitive ideas and images. My view in this essay is to provide a cross-section of ideas and works, whereby the reader might gain some insight into the varied nature of this kind of sculpture. Thus, there seemed very little need for endless similarities of concept and expression. It was the diversity which I felt was important. The chapter which discusses concepts of beauty is also not a comprehensive study. This subject demands more than a humble essay to do it any justice. However, my reasons for touching the vague and controversial outline of these concepts were, primarily, to suggest that notions of beauty as the sole criterion in the judgement of art are too limiting, and, consequently, to introduce the concept of vitalism, which I believe is more valid. Finally, I wish to mention the personal motive behind this work. Over the years, I have witnessed the emergence of brutal elements in my own work, which I found disturbing at times. I have never been able to answer satisfactorily the criticism I've received. All I knew was that these things came from a very deep source. It is with this in mind that I embarked on this project, hoping to achieve two things. Firstly, to provide an objective survey of an important development in art, and, secondly , to answer some of my criticism. Foreword, p. 1.
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Date Issued: 1987

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A survey of the curricula for the pre-service education of secondary school geography teachers in South Africa, with special reference to Transkei

- Mniki, Claribel Pumzile

Authors: Mniki, Claribel Pumzile
Date: 1987
Subjects: Education -- Curricula , Education -- South Africa -- Transkei , Black people -- Education -- South Africa -- Transkei , Geography -- Study and teaching (Secondary) -- South Africa -- Transkei , Teachers -- Training of -- South Africa -- Transkei
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1340 , http://hdl.handle.net/10962/d1001406
Description: Programmes designed for the pre-service education of secondary school geography teachers reflect the assumptions held by programme designers regarding the nature of education, teaching in general and geography teaching in particular. The general practice is that in universities, individual method lecturers design their programmes and in colleges within a department of education the programmes are centrally planned. Each programme focuses on a specific context. This, together with the autonomy enjoyed by university method lecturers in designing their courses, has resulted in the variations found in geography teacher education programmes. The evidence of this is found in the structure and duration of courses, the course content, the strategies used to educate teachers and the way in which the course is evaluated. This thesis is an attempt to establish consensus and divergence in pre-service education programmes for secondary school geography teachers regarding their organisation, specific knowledge imparted to student teachers; skills, values and attitudes developed. The pre-service education of secondary school geography teachers in South Africa is revealed in an analysis of views held by method lecturers, practising teachers in secondary schools, and student teachers and an analysis of course outlines , teaching practice assessment forms and geography method examination papers. Conclusions are drawn and recommendations made for improving the initial education of secondary school geography teachers in Transkei
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Date Issued: 1987

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The petrology and geochemistry of the upper critical zone of the Bushveld complex at the Amandelbult section of Rustenberg Platinum Mines Limited, Northwestern Transvaal, South Africa

- Field, Matthew

Authors: Field, Matthew
Date: 1987 , 2013-03-06
Subjects: Geology -- South Africa -- North-Western Transvaal , Petrology -- South Africa -- North-Western Transvaal
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5037 , http://hdl.handle.net/10962/d1007499 , Geology -- South Africa -- North-Western Transvaal , Petrology -- South Africa -- North-Western Transvaal
Description: A study of petrological and geochemical variations through the upper Critical Zone of the Bushveld Complex at Amandelbult section of R.P,M. was undertaken. The sequence at this locality may be divided into seven "units" two of which appear to be complete, possessing the sequence harzburgite-pyroxenite-norite-anorthosite. The other five Units lack basal, intermediate or upper members. Considerable lateral variations are apparent in this sequence, but these are restricted to the Lower Pseudo Reef-Merensky Reef interval, tne same portion of the succession which is affected by pothole structures. The single most important petrographic feature of genetic significance is the occurrence of annealed, recrystallized anorthosite immediately underlying ulstramafic layers. This, together with the undulatory nature of the contact between the two rock layers, suggests that the ultramafic layer was emplaced as a hot liquid over a pre-existing, crystalline anorthosite floor, and that some remelting of this layer occurred. Variations in the chemical make-up of constituent silicate minerals reveal a number of significant processes which may have been operative in the magma chamber prior to crystallization, Olivine grains, for instance, exhibit extremely wide chemical variations both within single layers and from one layer to the next. These variations are best explained by re-equilibration processes with spinel and base metal sulphides, rather than by wide variations in original liquidus compositions. It appears that the compositions of the initial liquids from which each basal olivine-bearing layer crystallized, were approximately similar. Variations in the iron-magnesium ratio of ortho-pyroxenes indicate well defined continuous fractionation trends in units which are considered to be complete. Magnesian compositions are recorded in ultramfic members, while increasingly iron-enriched values are recorded upwards through the sequence pyroxenite-norite-antorthosite. Plagioclase grains exhibit less well defined fractionation trends, but it is clear that an upward increase in An is encountered through indivitual Units. This is in direct contrast to the trend exhibited by orthopyroxene. A further feature of plagioclase grains is the considerable degree of chemical zonation exhibited by them. In cumulus grains this is commonly manifested as strongly reversed rims, while in intercululus grains normal zoning is ubiquitous. Whole-rock chemical variations through the succession indicate that cyclical variations occur through successive Units, but that these merely reflect changes in modal mineralogy and not liquid fractionation trends. Such trends can be shown for selected element ratios, where these elements are known to partition into a single mineral phase. Rations of pyroxene components such as the nickel/scandium ratio, exhibit a saw tooth pattern through successive Units, while ratios of plagioclase components such as the strontium/alumina ratio have unique, fairly constant values for each individual Unit but different values for successive Units. The latter type of cyclicity is not always strictly confined to lithologically recognized boundaries between Units, and a slight overlap into overlying ultramafic layers is apparent. An investigation of variations in trace element levels in a single layer in five widely separated boreholes revealed that there is some evidence for a lateral fractionation trend from the southwest (more primitive) to the northeast (more evolved), although the small number of data points available preclude definite conclusions. There exists in the data some evidence that the Giant Mottled Anorthosite differs chemically from the other anorthosites in the study section, and that it more closely resembles rocks of the Main Zone. This evidence is particularly apparent in variations of the chromium/aluminium ratio of orthoyroxene grains, and in the An content of plagioclase grains, both of whose trends exhibit distinct inflections at the base of this member. The features of the succession at Amandelbult are best explained by the model of Eales et al. (in press, a), which visualizes the input of a number of pulses of new, hot liquid into a magma chamber containing the fractionated residua of previous influxes. At a critical point in time, just prior to the mafic Merensky Reef input, a large input of gabboic liquid was intruded at high levels in the chamber. The lower portions of this liquid mixed with the residua of earlier mafic inputs, which in turn mixed with new inputs of mafic, typical Critical Zone liquids. Thus the lower portions of the study section represent mixtures of new Critical Zone liquids with the residua of previous such influxes, while the upper portions have the added complication of mixture with a Main Zone-type liquid. The unique chemical character of the Giant Mottled Anorthosite appears to be a direct manifestation of the influence of the Main Zone liquid. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Date Issued: 1987

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Some aspects of concept acquisition in history

- Macrae, Michael John

Authors: Macrae, Michael John
Date: 1987
Subjects: History -- Study and teaching -- South Africa , History -- Study and teaching -- Testing , History -- Study and teaching -- Methodology
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1367 , http://hdl.handle.net/10962/d1001433
Description: There is concern that school history is often purposeless, taught by chalk and talk and textbook methods, giving thin and unassimilated information. At a time when subjects are under increasing scrutiny and pressure to justify their existence as relevant in the school curriculum, many of the defects inherent in the 'traditional' approach to history have made it difficult to present a forceful and valid argument for its continued inclusion as a school subject.This has led to the adoption of new approaches which are designed to get pupils more actively involved in their learning. One such approach was adopted by the Schools Council 13-16 project in Britain. It laid emphasis on the methodology of the subject and identified five ways in which history could prove to be a useful and necessary subject for adolescents to study. These were: as a means of acquiring and developing such cognitive skills as those of analysis, synthesis and judgement; as a source of leisure interests; as a vehicle for analysing the contemporary world and pupils' place in it; as a means for developing understanding of the forces underlying social change and evolutioni and, finally, as an avenue to self-knowledge and awareness of what it means to be human (Introduction, p. ii)
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Date Issued: 1987

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