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Vegetation ecology of the Camdebo and Sneeuberg regions of the Karoo biome, South Africa

- Palmer, Anthony Riordan

  • Authors: Palmer, Anthony Riordan
  • Date: 1989
  • Subjects: Plants -- South Africa -- Great Karoo Great Karoo (South Africa)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4173 , http://hdl.handle.net/10962/d1002021
  • Description: An hierarchical syntaxonomic classification of the vegetation of the Camdebo and Sneeuberg regions of the karoo biome is presented as a second approximation after the earlier work by Acocks (1953). Details on the geomorphology, geology, climate, and early vegetation history of the area are given. The vegetation of the study area was stratified with the aid of Landsat imagery and the community classification was generated using two-way indicator species analysis (Twins pan) which produced ordered phytosociological tables. Tabular comparisons and final sorting of tables are according to the methods and techniques of the ZiirichMontpellier school of phytosociology. Syntaxonomic ranks are defined as five classes, nine orders and seventeen communities. The classes are Grasslands, Karoo Shrublands, Karoo Dwarf Shrublands, Sub-tropical Transitional Thicket, and Riparian Thicket. The distribution of syntaxa corresponds with the steep precipitation gradient experienced in the study area. These vegetation concepts are applied to the description of the flora of the Karoo Nature Reserve and an analysis of the total flora of the reserve is provided. The communities of the pediments, which contain the highest number of endemics, are poorly conserved. I test the validity of the vegetation classification by interpreting the results of an analysis of soils within the hypothesized vegetation units. There is a gradient of increasing Na, silt and pH levels from the Shrublands and Grasslands to the Succulent and Grassy Dwarf Shrublands of the pediments. A qualitative model of the vegetation history during the glacial-interglacial sequence in the Graaff-Reinet region of the eastern Cape is presented. Using a descriptive approach, the distribution patterns of 68 taxa, which are differential species for Karoo Shrublands, Succulent Thicket and Karoo Dwarf Shrublands, are investigated relative to major southern African biomes. The results indicate that a large proportion of the differential species in the phytosociological classification show affinity with Grassland and Savanna Biomes. Three species groups encountered in the Dwarf Shrublands show affinity with the Nama-Karoo biome. The differential species of the Succulent Thicket have a predominantly subtropical distribution. Using an historical approach, the palaeoenvironment of the region during the past 20 000 years is discussed briefly. On the basis of the descriptive and historical perspectives, a qualitative model of vegetation history is presented. The Succulent Thicket may have become established on edaphically favourable sites in the ameliorating conditions of the warmer, wetter Holocene subsequent to the Last Glacial Maximum. The Dwarf Shrubland and Succulent Dwarf Shrubland are depauperate in relation to ccmmunities in other southern African biomes, but the relatively large number of endemics suggests a long history in the region. Their differential species groups occur under arid conditions, accompanied by soils with high base and fertility status. The Dwarf Shrublands may have been more extensive during the drier glacial times on those sites currently occupied by Shrubland. The Shrublands display the expected affInity with the Grassland and Savanna Biomes. The small number of endemics suggest that these communities may have occupied the region in the period since the Last Glacial Maximum. Species with Succulent Karoo Biome affInity are poorly represented. The reliability of using Landsat products to detect and map the vegetation of the region is assessed. The manual classification of Landsat standard products provides a poor reflection of the vegetation of the arid, sparsely-vegetated bottomlands and pediments. The products provide good representation of the boundaries of thicket vegetation, but this uni-temporal approach does not distinguish between floristically different thicket communities. After analyzing digital Landsat data, I suggest that the multi-spectral scanner detects the boundaries of broad soil pedons and geological formations in areas of low vegetative cover. I describe and map the vegetation categories of the region after manual interpretation of six Landsat scenes. This is an effIcient, cost-effective method of mapping vegetation in extensive regions. The mapping units do not reflect the syntaxonomic classification, representing rather an integration of physiographic, pedological, geological and floristic information. With the view to improving the classification of these units, I develop a qualitative model of the natural resources of the region using an expert system
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  • Date Issued: 1989

Wealth or welfare?: a survey of local responses to government's proposed urbanisation policy in the greater Algoa Bay area

- Taylor, Beverley J

  • Authors: Taylor, Beverley J
  • Date: 1989
  • Subjects: South Africa -- Group Areas Act Urbanization -- South Africa Cities and towns -- Africa Freedom of movement Local government -- South Africa -- Eastern Cape Joint management centres South Africa -- Politics and government Algoa Bay (South Africa)
  • Language: English
  • Type: Book , Text
  • Identifier: http://hdl.handle.net/10962/1784 , vital:20225 , ISBN 0868101761
  • Description: This Working Paper sets out to investigate what has generally been taken for granted as part and parcel of the urbanisation and development process in South Africa, and to relate this to current government strategies. There has been no comprehensive policy for coping with urbanisation in South Africa. In particular, the urbanisation of Africans has not been accepted as an inevitable process. Instead, past policies have been guided by apartheid ideology and have tended to address only specific issues relating to urbanisation. Essentially, policies have attempted to control the urbanisation process through various pieces of legislation directed at, for example, housing, population migration, industrial decentralisation etc. Such legislative measures, rather than presenting a coherent urbanisation policy, have provided the main tools for the South African state to control and direct the urbanisation process in the country as a whole. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
  • Full Text:
  • Date Issued: 1989

Workers Tax - How to calculate your tax under the new SITE system

- TURP

  • Authors: TURP
  • Date: 1989
  • Subjects: TURP
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/135681 , vital:37288
  • Description: Through their organisations, workers have raised ill many problems with the tax system in South Africa. The main issue is that although everyone in South Africa pays tax, the majority of the people cannot choose their government and so they have no say in how their money is spent. Only 14% of South Africans can vote for the government. However, the government decides howto use everyones’ money. Clearly, then, the payment of tax is a political issue. Everyone should have an equal say in how their money is spent. Tax is also an issue that particularly concerns workers. Since the introduction, in 1988, of the Standard Income Tax on Employees (SITE), workers have had their tax assessed by their employers. How this happens and the problems that this can cause, are set out in this booklet. Many workers may have paid too much tax between March and July this year. They should be refunded the money. It is important to check and see if this has happened. The booklet will explain howtodo this and will teach people how to work out how much tax they should be paying. Tax is also being taken up as a womens' issue because married women pay more tax than anyone else.
  • Full Text:
  • Date Issued: 1989

Xinyimpfana xa Xikwembu

- Church Choir and Congregation, Composer not specified, Dargie, Dave

Yankele izipho zethu Nkosi

- Church Music Workshop Participants, Composer not specified, Mbobosi, Nomangesi, Dargie, Dave

Yazisa Uyihlo Nonyoko

- Sacred Music Festival Participants, Composer Not Specified, Dargie, Dave

Yihla Moya, usiKhumbule

- Church Music Workshop Participants, Composer not specified, Mbobosi, Nomangesi, Dargie, Dave

Zinc inhibition of cell division : its relevance to cancer cells and possible mechanism of action

- Skeef, Noel Samuel

  • Authors: Skeef, Noel Samuel
  • Date: 1989
  • Subjects: Cell division , Cancer cells -- Growth -- Regulation , Zinc in the body , Zinc -- Physiological effect , Cancer -- Research
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4144 , http://hdl.handle.net/10962/d1016266
  • Description: A description of two techniques used extensively in this study namely cell counting with a "cell counting plate" and argentation TLC for the separation of ω -6 -fatty acids is given. Zn supplementation into GM of two malignant (BL-6 and Hep- 350) and a non-malignant (LLC-MK) cell line/s resulted in an increased uptake of Zn by the cells and progressively suppressed proliferation of particularly the malignant cells. Zn chelation by EDTA suppressed in vitro proliferation of all 3 cell line, this effect being more pronounced in the malignant cells. A dietary Zn deficiency resulted in alopecia in mice and both a dietary Zn deficiency and Zn excess reduced growth of BL-6 tumours implanted subcutaneously in mice. Zn supplementation into GM progressively increased the uptake of [1-¹⁴C]-LA by BL-6 and LLC-MK cells but had a very slight though irregular effect on this parameter in the Hep- 350 cells. Zn supplementation also stimulated desaturase activity in the BL-6 cells. These results suggested that there are select cell lines whose Δ⁶-desaturase activity responds positively to Zn supplementation (e.g. the BL-6 cells). Delta-6-desaturase activity was also assayed in microsome preparations from different tissues. No enzyme activity was detected in the microsomes prepared from the BL-6 tumours. There was no significant effect with the addition of Zn or EDTA, on Δ⁶-desaturase activity of the regenerating liver microsomes. In the resting liver microsomes this enzyme activity was reduced only when EDTA and Zn were added together and when EDTA was added to the reaction medium as well as to the microsome preparations 2 hr before the enzyme activity assay was initiated. The results of these experiments suggested that the Δ⁶-desaturase enzyme in the microsome preparations may have had an adequate amount of Zn with further additions having no stimulatory effect on the enzyme. Two independent mechanisms of control of cell proliferation by low and high Zn are suggested to operate.
  • Full Text:
  • Date Issued: 1989

Records of the inquest into the murder of Matthew Goniwe, Sparrow Mkonto, Fort Calata and Sicelo Mhlauli near Port Elizabeth on 21 June 1985

DD134-02.mp3

- Andrew

  • Authors: Andrew
  • Identifier: http://hdl.handle.net/10962/314219 , vital:59575
  • Description: Composition Workshop Performance with Marimba and clapping accompaniment.
  • Full Text: false
  • Date Issued: 1989
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