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The reintegration of Walvis Bay and its Penguin/Off-shore Island into Namibia

- Kodisang, J M

  • Authors: Kodisang, J M
  • Date: 1996
  • Subjects: Penguin Islands , Walvis Bay (Namibia) -- International status , Namibia -- Politics and government , South Africa -- Foreign relations -- Namibia , Namibia -- Foreign relations -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2790 , http://hdl.handle.net/10962/d1003000 , Penguin Islands , Walvis Bay (Namibia) -- International status , Namibia -- Politics and government , South Africa -- Foreign relations -- Namibia , Namibia -- Foreign relations -- South Africa
  • Description: The thesis focuses upon the final reintegration of Walvis Bay and its twelve Penguin/Off-Shore Islands into Namibia. As Namibia's only deep water port, it escaped reintegration in 1989 when the United Nations Security Council Resolution (UNSCR) 435 (1978) was implemented. Hence the study argues that the exclusion of Walvis Bay from the Settlement Plan falls outside the parameters of various UNSC and UN General Assembly Resolutions, viz 385 and 432 of 1976 respectively. Such an arrangement has to be looked at as Pretoria's non-compliance with the above resolutions. South Africa got away with such an arrangement with the blessing of the Western Contact Group of Nations, i.e the United States; Britain; (former West) Germany; France and Canada. The argument advances further to capture the sudden emergence of Walvis Bay as a dispute between the National Party regime and the African National Congress (ANC) in particular. The dispute came about when the National Party submitted a controversial constitutional proposal during South Africa's transition to democracy at Kempton Park. They were proposing Walvis Bay to constitute part of the new Western Cape province in the postapartheid South Africa. Namibia's diplomacy paid off when the return of Walvis Bay was agreed upon as it became entangled in the constitutional talks for South Africa's transition to democracy at Kempton Park in 1993-1994.
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  • Date Issued: 1996

The reproduction biology of four species of South African dolphins

- Reddy, Kasturi

  • Authors: Reddy, Kasturi
  • Date: 1996
  • Subjects: Dolphins -- South Africa -- Reproduction , Bottlenose dolphin -- Reproduction , Striped dolphin -- Reproduction , Chinese white dolphin -- Reproduction
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5753 , http://hdl.handle.net/10962/d1005441 , Dolphins -- South Africa -- Reproduction , Bottlenose dolphin -- Reproduction , Striped dolphin -- Reproduction , Chinese white dolphin -- Reproduction
  • Description: Seasonality of reproduction in common dolphins (Delphinus delphis), bottlenosed dolphins (Tursiops aduncus), striped dolphins (Stenella coeruleoalba) and humpbacked dolphins (Sousa chinensis) was examined using standard light microscope techniques. In the males four stages of testicular development could be identified. Individuals less than 2.26m in length and 105kg in mass had testes that contained small seminiferous tubules (0.048mm ± O.Olmm in diameter) and were classified either as juveniles (gonocytes present) or inactive (no gonocytes). Adults whose testes contained spermatozoa were said to be in late spermatogenesis while those whose testes contained no spermatids or spermatozoa were referred to as being in early spermatogenesis. In the males of D. delphis, T. aduncus and S. chinensis, late spermatogenesis occurred throughout the year and there was no significant difference in the monthly mean seminiferous tubule diameters (p > 0.05) within species. I conclude therefore that in these three species spermatogenesis is aseasonal. No conclusions about seasonality of spermatogenesis could be made for S. coeruleoalba owing to the small sample size. Large Graafian follicles occurred in the ovaries of all four species in most months of the year. However, the presence of Graafian follicles can not be taken as an indication of timing of reproduction since they may be remnants of follicles that have not yet degenerated. In D. delphis, T. aduncus and S. coeruleoalba luteal bodies (corpora albicans or corpora lutea) occurred in most months of the year. Active corpora lutea will be present in all months, in some members of the population, since gestation is approximately 12 months. The sperm structure of D. delphis was examined by scanning electron microscopy. The sperm of D. delphis is essentially similar to that described for two other species of Cetacea (Physeter catodon and Tursiops aduncus), having an ellipsoidally shaped head and a short mid-piece with nine mitochondria. The sperm dimensions for D. delphis were head length, 4.4pm; head width, 2.0pm and mid-piece length, 2.4pm. An analysis of foetal age in D. delphis showed that the majority of the foetuses were conceived in January with birth occurring the following summer (December), suggesting that reproduction is seasonal. Neonates of T. aduncus were found throughout the year suggesting aseasonal reproduction. Foetal material was not available for S. coeruleoalba and S. chinensis. Seasonality of reproduction in the four species of dolphins studied has been discussed in relation to feeding, migration and worldwide distribution of the species.
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  • Date Issued: 1996

The role of microzooplankton in carbon cycling in the Southern Ocean

- Froneman, Pierre William

  • Authors: Froneman, Pierre William
  • Date: 1996
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:21066 , http://hdl.handle.net/10962/6234
  • Description: A 3-year study was carried out on the role of microzooplankton in carbon cycling in the south Atlantic and the Atlantic sector of the Southern Ocean. Microzooplankton grazing impact on phytoplankton was estimated during austral summer and winter employing the dilution technique. Carnivory by larger zooplankton on microzooplankton during summer was estimated using in vitro incubations. Microzooplankton assemblages were always dominated by protozoans comprising ciliates and dinoflagellates. In the ( 20 um chlorophyll fraction, microzooplankton grazing was sufficient to control the growth of the nano- and picophytoplankton suggesting that, where larger microphytoplankton cells dominate, micro zooplankton maintain the background concentrations of the nano- and picophytoplankton. During winter, when small nano- and picophytoplankton cells dominate total chlorophyll concentrations, the microzooplankton grazing impact on phytoplankton is dramatically increased. Microzooplankton removed on average 37% of the initial phytoplankton stock or 70% of the daily phytoplankton production. These results suggest that in winter, micro zooplankton are the main sink for phytoplankton production. Carnivory experiments conducted with selected meso- (copepods) and macro zooplankton (euphausiids and tunicates) showed that all species examined consumed micro zooplankton in the presence of substantial chlorophyll concentrations. Microzooplankton can, therefore, be regarded as trophic intermediates between bacterioplankton, small phytoplankton cells and larger zooplankton species in the Southern Ocean. The results of this investigation suggest a spatiotemporal shift in efficiency of the biological pump mediated by changes in the size composition of the phytoplankton assemblages. South of the Antarctic Polar Front (APF) large IV microphytoplankton cells dominate the summer chlorophyll biomass, suggesting that larger zooplankton grazers represent the main sink for phytoplankton production. Under these conditions, carbon flux to the interior of the ocean will be high due to diel vertical migrations by grazers and the production of large, fast sinking faecal pellets. The sedimentation of large phytoplankton cells also contributes to flux. In the permanently open waters south of the APF and throughout the Southern Ocean during winter, small phytoplankton cells dominate total chlorophyll, resulting in the microbial loop being the main sink for phytoplankton production. The close coupling between the micro zooplankton and the microbial loop dramatically reduces the transfer of organic carbon from the surface layers to depth. Carnivory by metazoans on microzooplankton may reduce the high grazing impact of micro zooplankton and, may also represent an important source of carbon flux originating from the microbial loop.
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  • Date Issued: 1996

The role of student writing in learning in zoology

- Moore, Robin Stanley

  • Authors: Moore, Robin Stanley
  • Date: 1996
  • Subjects: Zoology -- Study and teaching Communication in science -- Study and teaching Science -- Study and teaching
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1752 , http://hdl.handle.net/10962/d1003636
  • Description: In this study I attempt to develop a rationale for the role of student writing in advancing learning in Zoology. To this end, I use the informed and insightful voices of five academics from the University of Cape Town's Department of Zoology to present a picture of the goals of the discipline, how they view the role that student writing plays in advan~ing these goals, a sense of the tensions they face in dealing with student diversity, and the promise and challenges of innovative approaches. My interest in how staff view student writing stems from a belief that staff make use of student writing in different ways, depending on their assumptions about writing. I explore these assumptions by means of interviews with members of staff, in which I ask about how they understand the pursuit of science, the qualities a scientist needs to develop, the best ways to develop these qualities in students, and the part that student writing plays in this development. What emerges in this study is the understanding that the kinds of writing we ask students to do reflect the forms of educational practice that we sustain. On the one hand, certain forms of writing may support forms of transmission pedagogy that are viewed as being at odds with progressive science education. On the other hand, if we are to develop alternative teaching approaches which are in keeping with contemporary views of science and learning, then we need to develop new genres of student writing that give expression to these goals and methods. The study concludes with suggested avenues into curriculum review that would operationalise the insights developed by this study.
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  • Date Issued: 1996

The role of the cadence as determining factor of phrasing of the organ toccatas, preludes and fantasias of Johann Sebastian Bach

- Du Plooy, Jacobus Stephanus

  • Authors: Du Plooy, Jacobus Stephanus
  • Date: 1996
  • Subjects: Bach, Johann Sebastian, 1685-1750 -- Criticism and interpretation
  • Language: English
  • Type: Thesis , Masters , MMus
  • Identifier: vital:2636 , http://hdl.handle.net/10962/d1002301
  • Description: This study examines the phrasing of J.S. Bach's preludes, toccatas and fantasias for organ. Consequent upon Bach's silence on the subject and the inadequacy of available sources, the cadence has been used as a means to determine the phrasing of these works. The goal of this thesis is to identify those characteristics of the cadence that can assist the performer in two ways: On the one hand, to select the appropriate type of break between phrases, and, the other hand, selecting the appropriate changes in tempo and articulation essential to the shaping of phrases. The term, 'cadence', therefore, applies not merely to an isolated entity of two chords, but rather to a broader formula including the progressions towards and away from it. This investigation follows an eclectic approach. Accordingly, the exploration of various sources is combined with diverse methods of analyses. The first method is a detailed structural analysis of Bach's cadential progressions, and more specifically, the way in which he integrated the basic musical elements into them. This shows the points of tension and relaxation, two musico-psychological effects fundamental to any decision regarding phrasing. The second method puts Bach's cadences within the context of the larger musical structure, including the 'extra-musical' (i.e. grammatical, rhetorical and 'affective') forms. This method organises cadences according to their various punctuation functions, hence main and secondary cadences. The cadences of twenty-eight works - those works of which the authenticity is more or less secure - are analysed. Descriptions cover a selection from these works considered to be the most representative. A significant number of examples, induding performing suggestions, accompany and elaborate in detail on all descriptions of cadences. An application of the findings is presented by an analysis and di scussion that elaborates in detail on the suggested performance of two works, BWV 542 and 541. These two works epitomize, and simultaneously form the culmination of the two principal styles (i.e. the improvisatory and motorically-orientated) prevalent in Bach's free organ works. Examination of the findings of this study and implications for further research conclude this thesis.
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  • Date Issued: 1996

The significance of trade policy in promoting the international competitiveness of South African industry

- Hofmeyr, Lynne Mary

  • Authors: Hofmeyr, Lynne Mary
  • Date: 1996
  • Subjects: South Africa -- Commerce , South Africa -- Commercial policy , International trade
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2781 , http://hdl.handle.net/10962/d1002991 , South Africa -- Commerce , South Africa -- Commercial policy , International trade
  • Description: This study proposes to examme the significance of trade policy in promoting the international competitiveness of South African industry during the period from the early 1970s up until the present day. By providing a background of South Africa's past trade policies, it is argued that the origins of South Africa's low levels of competitiveness essentially lie in the apartheid years where trade policies were not linked to the attainment of international competitiveness and improved productivity. The study then reviews the development of South Africa's trade policies in the 1990s. In so doing, it reveals weaknesses in the areas of implementation which are critiqued in greater detail by using the clothing and textile industries as a case study, and other selected examples. The study finally concludes that trade policy is crucial to global competitiveness and that it is the responsibility of all parties concerned to ensure that trade policies enhance and not inhibit competitiveness.
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  • Date Issued: 1996

The social identity and inter-group attitudes of white English- and Afrikaans-speaking adolescents

- Smith, Timothy Byron

  • Authors: Smith, Timothy Byron
  • Date: 1996
  • Subjects: Afrikaners -- Ethnic identity , Whites -- South Africa -- Attitudes , Teenagers -- South Africa -- Attitudes , Youth -- South Africa -- Attitudes , Identity (Psychology) in adolescence , Prejudices -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:3059 , http://hdl.handle.net/10962/d1002568 , Afrikaners -- Ethnic identity , Whites -- South Africa -- Attitudes , Teenagers -- South Africa -- Attitudes , Youth -- South Africa -- Attitudes , Identity (Psychology) in adolescence , Prejudices -- South Africa
  • Description: Issues of group identity and prejudice have played a large role in the history of South Africa. To examine differences between White English- and Afrikaans-speaking adolescents within the context of the "new" South Africa, data was collected from 553 high school students using a questionnaire which assessed aspects of these groups' perceptions of themselves (their identities), attitudes toward other racial groups (their prejudices), and beliefs about their rapidly changing socio-political environment. A discriminant function analysis conducted with these variables correctly identified group membership at a rate much higher than chance (p < .00001). Post hoc univariate analyses indicated that compared with Afrikaans-speakers, English-speakers demonstrated significantly less identification with their own culture, less racial prejudice but also less willingness to make retribution to those who were oppressed by Apartheid, and less concern/confusion over the recent changes which have taken place in the country. Descriptive and correlational analyses also provided additional, valuable information regarding the variables assessed in the study. Overall, the results seemed to indicate that the adolescent subjects of this study find themselves in a state of transition.
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  • Date Issued: 1996

The taxonomy and life-history of Argyrosomus japonicus and A. inodorus, two important sciaenids off the South African coast

- Griffiths, Marc H

  • Authors: Griffiths, Marc H
  • Date: 1996
  • Subjects: Argyrosomus Sciaenidae -- South Africa Sciaenidae -- Namibia
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5323 , http://hdl.handle.net/10962/d1005169
  • Description: A study of the biology, anatomy and taxonomy of the sciaenid fishes of the genus Argyrosomus from South Africa and Namibia revealed that three species were confused under the name "Argyrosomus Izololepidotus (Lacepède 1801)". Comparison of morphometric and meristic data, otoliths, swim-bladders, drumming muscles, and other morphological features of specimens from southern Africa, Madagascar, the Mediterranean, the eastern Atlantic Ocean, Japan and Australia, revealed that "A. hololepidotus" is a complex of four species: A. japonicus (Temminck & Schlegel 1843), which occurs off southern Africa, Japan and Australia; A. inodorus sp. nov., which is known from Namibia to the Kei River (32°40'S) on the east coast of South Africa; A. coronus sp. nov., which is known from central and northern Namibia and Angola, and A. hololepidotus, which appears to be endemic to Madagascar. Both A. japonicus and A. inodorus are important recreational and commercial linefish species in South Africa. Although A. inodorus occurs on the east and west coasts of South Africa, and A. japonicus is found between Cape Point and Mozambique, the former species is abundant only between Cape Point and the Kei River, and the latter species from Cape Agulhas to northern KwaZulu/Natal. The life-histories of Argyrosomus japonicus and A. inodorus, within these respective ranges, were elucidated using length-at-age, reproductive, catch and effort, size composition, otolith dimension/fish length and tagging data. Median sizes at maturity (L₅₀) for A. japonicus were 920 mm TL (5 years) for males and 1070 mm TL (6 years) for females. All males >1100 mm TL (7 years) and all females >1200 mm TL (8 years) were mature. Females grew faster than males, but in both sexes growth slowed dramatically after maturity. Maximum age recorded was 42 years, but fish older than 27 years were rare. Adult A. japonicus were predominantly found in the nearshore marine environment, but also occurred in estuaries and in the surf zone. Spawning takes place in the nearshore environment, from August to November in Natal, and from October to January in the Southern and South-Eastern Cape regions. A large proportion of the adult population migrate to Natal to spawn, although spawning may continue once they return to the Cape. Early juveniles of 20-30 mm TL recruit into turbid estuaries along the entire east coast, possibly aided by olfactory cues. They appear to remain in the upper reaches of the estuaries where they find suitable food and refuge from predators until they grow to about 150 mm TL. Juveniles larger than this size were found in the middle and lower reaches of estuaries and also in the surf zone. Juvenile A. japonicus (<1000 mm TL) generally did not migrate long distances, but remained as separate sub-stocks until they reached maturity. A. inodorus grows more slowly than A. japonicus, and attains a lower maximum age (25 years) and a smaller maximum size (34 vs 75 kg). There was no significant difference between the growth rates of male and female A. inodorus. Those in the South-Westem Cape initially grew faster than those on the east coast, but growth slowed sooner in the former region with the result that these fish attained a smaller maximum size. Although ripe A. inodorus were sampled throughout the year, there was a distinct spawning season from August to December, with a peak in spring (Sept-Nov). Spawning occurred throughout the study area for this species, in <50 m depth. Size at sexual maturity for A. inodorus was smaller in the South-Eastern Cape than in the Southern Cape. Median size at maturity for females was attained at 310 mm TL (1.3 years) in the former and at 375 mm TL (2.4 years) in the latter region, and the length at which all females were mature was 400 mm (3.5 years) and 550 mm (4.7 years) respectively. For males the estimates of Lso and total maturity were 200 mm (1 year) and 400 mm (2.8 years) for the SouthEastern Cape and 250 mm (1.5 years) and 450 mm (3.4 years) in the Southern Cape. East of Cape Agulhas, A. inodorus was found from just beyond the surf zone to depths of 120 m. Adults occurred predominantly on reef (>20 m) while juveniles were found mainly over soft substrata of sand/mud (5-120 m depth). Early juveniles do not enter estuaries, but apparently recruit to nursery areas immediately beyond the backline of breakers (5-10 m depth), and then move seawards with growth. No juveniles were obtained from the area west of Cape Agulhas as substrates <200 m depth were unsuitable for trawling. Due to lower water temperatures, the adults in this area were found from within the surf zone to depths of only 20 m. East and west of Cape Agulhas there was evidence of offshore dispersal in winter, in response to oceanographic changes. Based upon otolith morphology, juvenile and adult distribution patterns, sizes at sexual maturity and on tagging data, A. inodorus between Cape Point and the Kei River apparently exist as three separate stocks, one in the South-Eastern Cape, one in the Southern Cape and one in the South-Western Cape, with limited exchange. The life-histories of A. japonicus and A. inodorus are discussed in terms of their management. The large size at maturity of A. japonicus together with evidence for considerable human impact on the early juvenile, juvenile, and the adult phases of the life-cycle indicate that estuarine nursery habitats need to be conserved, that the minimum size limit should be increased, and that current bag limits for this species should be reviewed. Although the current minimum size limit provides protection for A. illodorus until maturity, evidence is presented which indicates that at least one and possibly all of the stocks of this species are currently over-exploited. Stock assessment of the South African A. japonicus and A. inodorus resources, and the implementation of effective management strategies, are therefore a matter of urgency.
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  • Date Issued: 1996

The use of wood ash for the protection of stored cowpea seed (Vigna unguiculata (L.) Walp.) against Bruchidae (Coleoptera)

- Katanga Apuuli, J, Villet, Martin H

  • Authors: Katanga Apuuli, J , Villet, Martin H
  • Date: 1996
  • Language: English
  • Type: Article
  • Identifier: vital:6864 , http://hdl.handle.net/10962/d1011196
  • Description: Dry wood-ash has been reported to provide effective, cheap and safe control of several pests of stored seeds by providing mechanical protection, especially if it is thoroughly mixed with the seed. Mixtures of seed and either clays, ash, talc, or sand are among the earliest recommendations for controlling bruchids in beans (Metcalf 1917; Headlee 1924; Subramanian 1935; Deay & Amos 1936; Lever 1941). Such use of ash has been reported on subsistence farms in Uganda (Davies 1970). However, little is known of the actual ratios of ash and beans needed for effective protection, or of the mechanism of protection. These issues motivated this investigation.
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  • Date Issued: 1996

Three dimensional kinetic analysis of asymmetrical lifting

- Li, Jian-Chuan

  • Authors: Li, Jian-Chuan
  • Date: 1996
  • Subjects: Lifting and carrying , Human engineering , Materials handling , Manual work
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5174 , http://hdl.handle.net/10962/d1018240
  • Description: Manual lifting is dynamic in nature and involves asymmetrical loading of the human body. This study investigated kinematic and kinetic characteristics of asymmetrical lifting in three dimensions, and then constructed a 3-D biomechanical force model of the lower back which is capable of quantifying torsional stress on the human spine. Eleven healthy adult male manual workers were recruited as subjects and lifted a 1 Okg load placed at the sagittal plane (0°) and at 30°, 60° and 90° lateral planes to the right, from 150mm and 500mm initial lift heights, respectively, to an 800mm high bench in the sagittal plane. Subjects' spinal motions and the trajectorial movements of the load in three-dimensional space were monitored simultaneously by a Lumbar Motion Monitor and a V-scope Motion Analyzer. Generally, the spinal motion factors increased as a function of increasing task asymmetry and differed (p < 0.05) between the lower (150mm) and higher (500mm) levels in the sagittal plane. In all asymmetrical conditions the motion factors showed a dramatic increase at the 500mm level compared to the increase at the 150mm level. The rates of increase in the horizontal and frontal planes were greater than those in the sagittal plane. Task asymmetry had a significant effect on the spinal kinematic parameters in the frontal plane at the two lift heights, and only at the high level (500mm) in the horizontal plane, with exception of average acceleration . Initial lift height exerted a significant effect on peak velocity and acceleration in both frontal and horizontal planes and on range of motion in the horizontal plane. Kinetic characteristics of the object being lifted in three-dimensions increased with an increase in task asymmetry. The increase was more dramatic in the lateral direction in the horizontal plane. However, motion factors in the vertical direction dominated the full range of the lift, irrespective of task asymmetry and lift height. The kinetic measures differed (p < 0.05) between the lower ( 1 50mm) and the higher (500mm) levels in the vertical direction except for average force. Task asymmetry had a significant effect on dynamic measures in the anterior-posterior direction. Both task asymmetry and lift height had a significant effect on dynamic motion factors in the lateral direction. From insights gained in the empirical study a three-dimensional biomechanical force model of the lower back was constructed based on a mechanism of muscle force re-orientation in the lumbar region. Acknowledging that the lower back is designed to be able to rotate around its longitudinal axis, the proposed model accounts for compression and shear forces and a torsional moment. The model has similar predictability to Schultz and Andersson's (1981) model when the human trunk exerts only a flexion-extension moment in the sagittal plane, but additionally predicts dramatic increases in shear forces, oblique muscle forces and torsional moment under asymmetrical lifting conditions which the Schultz-Andersson model does not. The increase rates in these forces and moment are not linearly related over task asymmetric angle.
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  • Date Issued: 1996

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- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

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- Dinah, Group Composition, Dargie, Dave

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- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

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- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

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- Nonine, Dinah, Group Composition, Dargie, Dave

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- Hogsback festival participants, Nofetyi, Dargie, Dave

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- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

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- Hogsback festival participants, Composer not specified, Dargie, Dave

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- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

Title not specified

- Ngqoko music ensemble participants, Composer not specified, Dargie, Dave

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