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Reform and democracy in Mozambique, 1983-1991

- Morgan, Glenda Nadine

Authors: Morgan, Glenda Nadine
Date: 1992
Subjects: Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2809 , http://hdl.handle.net/10962/d1003019 , Mozambique -- Politics and government -- 1975-1994 , Mozambique -- Economic conditions -- 1975-
Description: Africa is currently experiencing a movement toward more democratic systems of government. The causes of such changes are numerous, but the literature on African democratization, like that on similar changes elsewhere in the world, places emphasis on the role of internal or domestic factors. The role of international pressures toward democratization is almost completely ignored. The case of Mozambique illustrates the dangers of such an omission. During the past decade Mozambique has undergone considerable political change. The single-party, Marxist-Leninist oriented state has been replaced by a multi-party system, devoid of explicit references to any guiding ideology. The government has also expanded its contacts with the West, particularly by means of its assuming membership of the International Monetary Fund and the World Bank. These changes in Mozambique's political orientation have been accompanied by economic reforms, designed to arrest the precipitous decline in the Mozambican economy. In this dissertation I argue that the causes of both the economic and political reforms lie in this decline and in the government's need to secure capital and debt relief internationally. In order to do this, the Mozambican government had to change the aspects of its political system which were seen as being unacceptable by the West, in particular the lack of multi-party competition and its overtly Marxist orientation and close ties to socialist countries. Because the reforms had their primary genesis in Mozambique's need for international acceptance and not in the growth of popularly based democratic organisations, the reforms are fragile and their meaningfulness questionable.
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Date Issued: 1992

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Regulation of the indoleamines by sex steroids

- Awah, Edmund Kpabi

Authors: Awah, Edmund Kpabi
Date: 1992
Subjects: Steroids -- Research , Steroid drugs -- Research
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4053 , http://hdl.handle.net/10962/d1004114 , Steroids -- Research , Steroid drugs -- Research
Description: Alteration of serum tryptophan leads to parallel alterations in brain tryptophan levels. Such changes in brain tryptophan levels has been shown to lead to mood disturbances. The primary enzyme responsible for altering serum tryptophan levels is the liver cytosolic enzyme, tryptophan pyrrolase. Activation of this enzyme is responsible for the enhanced catabolism of circulating tryptophan. The purpose of the present study was firstly to establish whether there is a link between sex steroids and tryptophan pyrrolase activity especially since sex steroids are also known to cause mood disturbances and secondly to determine the effects of sex steroids on brain indolamine metabolism. The results show that all three sex steroids induce the activity of tryptophan pyrrolase implying that they decrease serum tryptophan levels by the activation of tryptophan pyrrolase, thus making less tryptophan available for uptake by the brain. It was also shown that the sex steroids enhance the uptake of ¹⁴C-tryptophan by brain synatopsomes. In addition, the sex steroids influenced the pattern of metabolism of serotonin by organ cultures of rat pineal glands. It is possible that the sex steroids regulate the availability and uptake of indoleamines in the brain.
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Date Issued: 1992

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Remote sensing of algae in inland southern African waters

- Quibell, G. E

Authors: Quibell, G. E
Date: 1992
Subjects: Algae -- Remote sensing , Algae -- South Africa , Freshwater algae -- South Africa
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5752 , http://hdl.handle.net/10962/d1005440 , Algae -- Remote sensing , Algae -- South Africa , Freshwater algae -- South Africa
Description: Routine monitoring of algae in inland waters in southern Africa is a critical element in assessing the efficacy of eutrophication management options. Several authors have indicated that single point samples are not necessarily representative of conditions throughout the water body and some have suggested remote sensing as a means of overcoming this problem. Remote sensing of algae normally involves deriving the empirical relationship between radiance detected at a sensor, and contact sensed chlorophyll concentrations. Quantification of, or compensation for, contributions to the upwelling radiance other than that light reflected by the algae is critical for this approach. In southern Africa these contributions arise primarily from atmospheric effects and from scattering by sediments in the water. A review of the atmospheric correction models suggested that a cosine sun angle correction followed by dark pixel subtraction is the most feasible method to compensate for the former effects. Studies of the changes in upwelling radiance induced by addition of sediment to algal cultures indicated that subtraction of reflectance at ≈665nm from that at ≈700nm, may provide a means of compensating for the scattering by sediments. The disadvantage of this approach is that few sensor systems have narrow spectral bands centred at these wavelengths. Investigations of the nature of the reflectance from 5 algal species indicated that all had similar reflectance spectra, but the blue-green genera had a smaller peak at ≈650nm. Chlorophyll absorption at ≈665nm was evident by lower reflectance at this point, but the alga Microcystis sp. did not conform to the conceptual model of reflectance, in that reflectance at 665nm was higher at increased cell density. Spectra of natural waters confirmed the results obtained in the laboratory. Reflectance at ≈700nm showed the largest changes with increasing chlorophyll concentration and also had the highest correlations to chlorophyll concentrations. However, due to the strong absorption of these wavelengths by water, this reflectance peak only occurred when sufficient cells were found in the upper layers of water. Use of these wavelengths in remote sensing models should therefore be restricted to highly eutrophied waters. Although the reflectance spectra of different algae were similar, the amount of light scattered by each species (measured as turbidity) differed for any given chlorophyll concentration. This appeared to be due to the colonial nature of the cells and means that empirical models will be unique to the species on which they were developed. Comparisons of multispectral photography (MSP) and LANDSAT MSS imagery indicated the MSP data had higher correlations with chlorophyll concentrations than did the MSS data. Chlorophyll simulations from a test set of data using ordinary multiple regression showed that the MSP imagery had mean errors of 7.3M9/I, while that for the MSS imagery was 7.4M9/I. Similar tests using the canonical procedure produced larger mean errors of 9M9/I and 12M9/I for the MSP and MSS data respectively. This was due to the fact that the canonical procedure is not suitable for the spectral band widths of these sensors. In spite of similar simulation accuracies, the MSS imagery produced very patchy synoptic views. This was due to the lower variance (radiometric resolution) in the LANDSAT MSS data. This appears to be the most important criterion for accurate chlorophyll mapping in inland waters. Development of a single multidate algorithm for southern Africa is not yet feasible, and routine monitoring of chlorophyll using these techniques is impractical. However acceptable chlorophyll maps are possible if the model is recalibrated for each occasion and the sensor used has a high radiometric resolution.
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Date Issued: 1992

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Selecting educational computer software and evaluating its use, with special reference to biology education

- Beyers, Ronald Noel

Authors: Beyers, Ronald Noel
Date: 1992
Subjects: Biology -- Study and teaching -- Computer programs Education -- Data processing Biology -- Computer-assisted instruction
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1764 , http://hdl.handle.net/10962/d1003649
Description: In the field of Biology there is a reasonable amount of software available for educational use but in the researcher's experience there are few teachers who take the computer into the classroom/laboratory, Teachers will make use of video machines and tape recorders quite happily, but a computer is a piece of apparatus which they are not prepared to use in the classroom/laboratory. This thesis is an attempt to devise an educational package, consisting of a Selection Form and an Evaluation Form, which can be used by teachers to select and evaluate educational software in the field of Biology. The forms were designed specifically for teachers to use in preparation of a computer lesson. The evaluation package also provides the teacher with a means of identifying whether the lesson has achieved its objectives or not. The teacher may also be provided with feedback about the lesson. The data is gathered by means of a questionnaire which the pupils complete. It would appear that teachers are uncertain as regards the purchase of software for their subject from the many catalogues that are available. The evaluation package implemented in this research can be regarded as the beginnings of a data base for the accumulation of information to assist teachers with details on which software to select. Evidence is provided in this thesis for the practical application of the Selection and Evaluation Forms, using Biology software.
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Date Issued: 1992

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Sensitivity of different areas of the flexor aspect of the human forearm to corticosteroid-induced skin blanching

- Meyer, Eric, Smith, Eric W, Haigh, John M

Authors: Meyer, Eric , Smith, Eric W , Haigh, John M
Date: 1992
Language: English
Type: Article
Identifier: vital:6394 , http://hdl.handle.net/10962/d1006317
Description: The intensity of corticosteroid-induced blanching has been found to vary at different areas of the flexor aspect of the human forearm. A retrospective analysis of 38,880 observations of skin blanching in 56 volunteers was conducted to assess the sensitivity of forearm skin to betamethasone 17-valerate. The mid-forearm appears to be more sensitive to the blanching response than do the areas close to the wrist or elbow. These results indicate that each preparation under evaluation should be applied to several sites along the forearm when using the human skin blanching assay in order to obtain an accurate comparative assessment of corticosteroid release from topical delivery vehicles.
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Date Issued: 1992

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Small-scale gold mining in southern Africa

- Joubert, Barend Daniel

Authors: Joubert, Barend Daniel
Date: 1992
Subjects: Gold mines and mining -- South Africa , Abandoned mines , Abandoned mines -- South Africa
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5002 , http://hdl.handle.net/10962/d1005615 , Gold mines and mining -- South Africa , Abandoned mines , Abandoned mines -- South Africa
Description: The general characteristics of gold deposits are reviewed, and a classification of gold deposits based on mineability is proposed. Evaluation, mlnlng and beneficiation methods are briefly discussed. It is concluded that the most viable targets for small-scale companies comprise deposits that require the least pre-production time and expense. Great potential exists for the small-scale reclamation of gold from tailings dumps and abandoned mines in Southern Africa. There is also potential for developing new smallscale gold mines in the Archaean greenstone terranes of the Zimbabwean and Kaapvaal cratons.
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Date Issued: 1992

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Social development: theory, practice and evaluation

- Henderson, Thelma M

Authors: Henderson, Thelma M
Date: 1992
Subjects: Social service -- South Africa -- Grahamstown , Social service -- Evaluation , Community development -- South Africa -- Grahamstown , Rhodes University. Centre for Social Development
Language: English
Type: Thesis , Masters , MSocSc
Identifier: vital:697 , http://hdl.handle.net/10962/d1006418
Description: Prior to 1976 few facilities and projects existed to serve the underprivileged communities in Grahamstown. Numerous attempts to establish development programmes had failed. From 1976 to 1981 informal attempts were initiated and a number of community based facilities were established. From 1981 to 1991 the Centre for Social Development assumed responsibility for this work and was able, with an enlarged staff, to inaugurate a wide range of projects and programmes. These cater to thousands of deprived people and enable them and their children to realise an improved quality of life. The dynamic processes and policies which have been employed are investigated. The value of this work is noteworthy because of the limited number of research papers on indigenous grassroots development projects in South Africa. The methods which have been utilised to enable unemployed people to play meaningful roles in their own communities are investigated. These include the establishment of much needed facilities and the in-service training of workers and committee teams to run and service them. Of particular importance is the role and structure of the Centre as an umbrella and resource organisation. The work of the Centre and its projects is described and evaluated. The qualitative, quantitative, exploratory and descriptive methods are used. The relationships between social welfare, community work and social planning are considered in relation to the theoretical base of the Centre. The situation in the Black and Coloured townships of Grahamstown, where most of the projects are located, is described with special reference to population, housing, basic services, crime and disease. Reasons for the high unemployment rates are enumerated. Various development models are described and their strengths and weaknesses assessed. Of particular significance are the origins of the Centre, the qualities brought to the project by the founding Director, its fundraising techniques, and procedures for training, supervision and project support. Aspects of development strategy not stressed in the literature, but of particular importance in the South African situation, are highlighted. These include the basic necessity for adequate financing, the provision of bursaries for tertiary study, the importance of nutritious food, the creation of job opportunities and the value of child centred projects as an access to the wider community. The necessity of financial control in the individual projects is also stressed. The primary aim of this work is to ascertain how projects have been established and maintained in a community where nothing on this scale has been attempted before. A secondary objective has been to find the theoretical base that best suits the work of the Centre. This is the social planning model in the social welfare field
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Date Issued: 1992

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Southern African Journal of Gerontology, volume 1, number 1, October 1992

- Ferreira, Monica (editor), Moller, Valerie, HSRC/UCT Centre for Gerontology

Authors: Ferreira, Monica (editor) , Moller, Valerie , HSRC/UCT Centre for Gerontology
Date: 1992
Subjects: Older people -- Care -- South Africa , Gerontology -- South Africa
Language: English
Type: Text
Identifier: vital:8065 , http://hdl.handle.net/10962/d1012658
Description: Southern African Journal of Gerontology; Produced within the framework of the Co-operative Research Programme on Ageing , The broad social issue of generational competition versus generational interdependence is discussed. The way elders are housed offers an excellent example of how benefits putatively allocated to older people in fact more often than not subsume benefits to family members of all ages. Data on generationally shared households from a number of countries and the results of recent studies from the United States are discussed in this context. Separate housing of generations is often preferred where feasible. Where economic, environmental. health, or social needs of either elder or young generations make autonomous households dysfunctional, members of each generation show in their household-formative behaviour their willingness to assist the other generation .
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Date Issued: 1992

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Standardization of Raven's standard progressive matrices for secondary school African pupils in the Grahamstown region

- Vass, Vasili Arthur

Authors: Vass, Vasili Arthur
Date: 1992
Subjects: Black people -- Education -- South Africa , Intelligence tests -- South Africa , Educational tests and measurements -- South Africa , Cognition and culture , Raven's Progressive Matrices
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3078 , http://hdl.handle.net/10962/d1002587 , Black people -- Education -- South Africa , Intelligence tests -- South Africa , Educational tests and measurements -- South Africa , Cognition and culture , Raven's Progressive Matrices
Description: Arising out of a need, expressed by Clinical Psychologists in the Grahamstown region, for the fair assessment of secondary School African pupils, norms for the Raven's Standard Progressive Matrices (SPM) were established. Two methods of presentation were used, the first using the original instructions of John Raven translated into the students' first language of Xhosa, hence-forth referred to as the Alternate sample. The second method of presenting the instructions was adapted, to include the use of visual aids and active participation in the instruction phase of the test, hence-forth referred to as the Normative sample. In addition to the establishment of norms, the two methods of test presentation were investigated to see if the method of presentation had an effect on the results of the Raven's SPM. The population was drawn from the three African Secondary Schools in the Grahamstown municipality. The total population consisted of 3 232 students. Classes were randomly sampled across the three schools, with the average age of the Normative sample being 19.3 years. The sample consisted of 812 pupils, 711 in the Normative sample and 101 in the Alternate Sample. The following results and conclusions arose from the study: 1) Norms generated were considerably lower than previously established norms in similar studies. 2) t-Test results indicated that the method of test presentation on the Raven's SPM is important when assessing students that may be regarded as 'disadvantaged'. 3) Respondents scored significantly higher when the method of presenting the instructions ensured a greater understanding of the task demanded of the respondents. 4) The analyses of covariance indicate that male subjects score significantly higher than female subjects, and that there is a significant difference between the ages and educational standard, on the scores of the Raven's SPM. 5) The differences found contradict previous findings using the test, and question the cultural fairness of the test.
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Date Issued: 1992

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Structural analysis of some Escherichia coli capsular antigens

- Hackland, Peter Linton

Authors: Hackland, Peter Linton
Date: 1992
Subjects: Antigens , Enterobacteriaceae , Escherichia
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3758 , http://hdl.handle.net/10962/d1003236 , Antigens , Enterobacteriaceae , Escherichia
Description: The work presented in this thesis forms part of a collaborative effort to determine the chemical structures of the surface antigens of bacteria which belong to the Enterobacteriaceae. These antigens are largely polysaccharides and occur as lipopolysaccharides and capsular polysaccharides which give rise to the somatic or 0 antigens and the capsular or K antigens, respectively. In recent years interest has mostly been focused on the extracellular polysaccharide antigens expressed by the genus Escherichia coli because of the effect they exert on normal immunological processes and their structural relatedness to the surface antigens of other more pathogenic bacteria. Therefore the molecular structures of the capsular polysaccharides (Kantigens)produced by E. coli 09:K35(AI04a) and 09:K38(A262a) have been determined by novel enzymic, chemical and spectroscopic procedures. These investigations show that the structures of these polysaccharides can be determined by a combination of chemical and spectroscopic procedures , or almost entirely by n.m.r. spectroscopy alone. The in vitro bacteriophage mediated depolymerisation of the native E. coli K35 polysaccharide demonstrates the value of this method for the isolation of oligosaccharides representing the repeating- unit and multiples thereof. Finally E. coli K37 and K38 capsular polysaccharides were used as model compounds for the evaluation of partial and selective reductive cleavage as methods of generating oligosaccharide for further structural analysis. The products of these reactions were analysed largely by a combination of mass spectrometric procedures.
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Date Issued: 1992

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Sylvia Plath images of life in a poet of death

- Mather, Mary Lynn

Authors: Mather, Mary Lynn
Date: 1992
Subjects: Plath, Sylvia , Plath, Sylvia -- Criticism and interpretation
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2245 , http://hdl.handle.net/10962/d1002288 , Plath, Sylvia , Plath, Sylvia -- Criticism and interpretation
Description: On a creative and a personal level, Sylvia Plath seems to have been fascinated by the relationship between life and death. Her work reflects an ongoing preoccupation with duality and a sense of tension between two opposing forces suffuses virtually every poem she wrote in the period from 1956 to early 1963. Because her attitude to both life and death is deeply ambivalent, Plath's poetry rests on a strong awareness of conflict and her art is characterized by a continual pull between extremes. This thesis is an examination of how she uses images of life in poems that ostensibly deal with death.While Plath draws on the events of her own life for her poetic material, she also converts her personal experiences into a universal myth. She was familiar with Robert Graves's eclectic study of the pagan nature deity, The White Goddess, and she seems to have incorporated part of his symbolism into her own code of images. In particular, she adopts Graves's triple goddess of nature as one of the dominant figures in her created world, for the White Goddess is associated with life and death alike.Plath's dichotomy of life and death works on different planes. Firstly, she frequently envisages the self as divided and the opposition between life and death takes on the dimensions of an internal psychological war. Secondly, she extends the battle between life and death to the creative sphere. Thirdly, she explores the idea of life as a journey from birth to death. The White Goddess is linked with the three natural realms of earth, sky and underworld. And Plath relies largely on seasonal, lunar and chthonic images in her poetry. Furthermore, the three colours of the goddess - white , red and black - are the dominant hues of her poetry.
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Date Issued: 1992

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The "Big E": the English (first language) endorsement on the teacher's bilingualism certificate: an investigation into the background to and origin of this requirement, an evaluation of past and current examining practices and standards and criteria, a needs assessment, and suggestions and recommendations for sound practice

- Spingies, Conrad

Authors: Spingies, Conrad
Date: 1992
Subjects: Teachers -- Training of -- South Africa Teachers -- Selection and appointment Teachers -- Language Teachers -- Certification -- South Africa Bilingualism -- South Africa
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1427 , http://hdl.handle.net/10962/d1003308
Description: South African education authorities demand of teachers a high degree of competency in both official languages. In the Cape Province in particular, teachers are not considered eligible for promotion posts unless they possess the so-called Higher Bilingualism Certificate, signifying their command of both official languages at "First Language" level. In view of the fact that the overwhelming majority of schools nowadays are single-medium institutions; this requirement may strike the objective observer as an anomaly. An attempt was made, therefore, first of all to investigate the historical background to this requirement. The "language question", a problematic feature of South African education since the beginning of the nineteenth.century, was not resolved when legislators chose "bilingualism and language equality" for the Union of South Africa in 1910. The available evidence suggests, however, that bilingualism was actively pursued as an educational ideal at least until the end of the 1940s, and for this reason education authorities placed a high premium on teachers who were "fully bilingual". Nowadays the typical (White) school is a single-medium institution where the second language is rarely if ever heard outside the classroom where it is taught as a subject. The present policy, to demand a high degree of proficiency in both official languages of teachers occupying promotion posts at such a school, may then be described not only as an anomaly, but as an anachronism. A further problem is the fact that the various educational institutions (specifically teachers' colleges and universities) that set examinations leading to the Higher Bilingualism Certificate rarely communicate with one another, and are therefore unable to agree on uniform standards and criteria, or to ensure that such standards are maintained. That this is indeed the case, was confirmed by examination of "Big E" test papers set at three teachers' colleges, two Colleges for Continued Training, and four universities in the Cape Province. In an attempt to establish what assistance and support might be needed by a "second language" user of English in order for him to improve to the point where he resembled a "first language" user of English in his "terminal language behaviour", a comparison (by means of error analysis) of the responses of two groups (an Ll and an L2 group) to the same test paper was undertaken. The available evidence suggests that L2 users may need to be helped to acquire a more extensive vocabulary, but, above all, that they need to improve their ability to handle two crucially important aspects of usage: idiom and grammar. The final chapter attempts to establish pedagogic and linguistic bases for a course intended for "Big E" candidates, and makes recommendations with regard to (i) the content and the form of the course, and (ii) sound examination practice. The concluding thoughts offer the view that such a course could remain useful even in a future South Africa where the emphasis may shift from a demand for teachers who are "fully bilingual" to teachers who have a good command of English.
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Date Issued: 1992

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The administration and organisation of independent study topics with special reference to secondary school geography

- van Harmelen, Ursula

Authors: van Harmelen, Ursula
Date: 1992
Subjects: Geography -- Study and teaching (Secondary) , Project method in teaching
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1419 , http://hdl.handle.net/10962/d1003300
Description: Traditional school subjects are having to compete for a place in a curriculum which is increasingly judged according to its perceived utilitarian value. According to current educational theory, geography's role in the curriculum is to develop concepts, skills, values and attitudes that allow pupils to understand the human and environmental issues which face their communities and communities throughout the world. In order to achieve these aims, teachers need to adopt a learner-centred teaching approach, yet geography teachers are faced with the dilemma of having to develop participatory teaching strategies within an existing structure which is largely product oriented. This thesis attempts to illustrate how changes can be effected in the approach to the teaching of geography, while working within existing syllabus constraints and while continuing to meet the demands made by the current examination system. To this end, Independent Study Topics are analysed as a means to bring about the desired changes in geographical education. The concept, Independent Study Topics as a 'blanket term' (Diepeveen, 1986) for pupil-centred activities is relatively recent in terms of the South African geography syllabus. In order to obtain greater clarity about the concept and its implications for geography teaching, this study examines current geographical theory relating to learner-centred approaches and relates them to teachers' perceptions of the role of IST in the geography curriculum. The second aspect of the study is concerned with the implementation of Independent Study Topics in a classroom research setting. The organisation and administration of Independent Study Topics in a single school setting is analysed and evaluated as a process of change. This analysis provides guidelines for developing a learner-centred approach which is necessary to ensure that geography retains its position in the school curriculum of the 1990's and beyond.
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Date Issued: 1992

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The anatomy and ecophysiology of Mariscus congestus from three different habitats in the Albany and Bathurst districts of the Eastern Cape, investigated under field and laboratory conditions

- Sonnenberg, Bernd Jürgen

Authors: Sonnenberg, Bernd Jürgen
Date: 1992
Subjects: Cyperaceae -- South Africa , Plant anatomy , Plant physiology
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4229 , http://hdl.handle.net/10962/d1003798 , Cyperaceae -- South Africa , Plant anatomy , Plant physiology
Description: An investigation of the anatomy and gas exchange characteristics of Mariscus congestus in three different habitats was undertaken in order to establish whether M. congestus from the three different habitats displayed any ecotypic responses when placed in a new similar environment. It was hoped that the results of this investigation would yield evidence that would support the ecotype concept similar to the investigations of Milner and Hiesey (1964), Green (1969) and Slayter and Ferrar (1977). On the basis of the site leaf anatomy, M. congestus investigated at the coast (site 1) differed in many respects from the inland plants (sites 2 and 3). These differences suggest that the coastal plants may have undergone a slight ecotypic divergence from the inland plants. The anatomical investigation also suggested that the leaves of M. congestus from all three sites may either be C₄ NADP-ME or PCK and that all had typical Chlorocyperiod anatomy. The habitat microclimates at sites 1-3 had different light and water regimes. There were no significant differences between the 12 month temperature environments of the three sites. There was however, a minor difference between the coastal (high temperature) and the inland (lower temperature) sites. M. congestus at the three sites had significantly different CO₂ assimilation rates, transpiration and stomatal conductance in response to the differing habitat microclimates. The water use efficiency of the sites were however, similar. Site 1 attained the highest CO₂ assimilation rates, transpiration, stomatal conductance, and water use efficiency and site 3 the lowest. Under similar conditions the gas exchange data for the potted plants indicated that M. congestus from the different sites was typically C₄. The optimal photosynthetic temperatures of all the sites was above 30°C and they did not show significant inhibition of CO₂ assimilation by different oxygen concentrations. The results of the laboratory investigation of the potted plants suggested that the only site-specific (ecotypic) response of M. eongestus was the light intensity at which the plants from the different sites were light saturated. The light and temperature response of field plants under field conditions was not comparable to the light and temperature response of potted plants under laboratory conditions. This may have been due to the field results being obtained under differing water and soil nutrient regimes. The potted plants may also have had a reduced root mass compared to their field counterparts and the potted plants may have also have become root bound. Under field conditions the plants had differing light saturation points and optimal photosynthetic temperatures compared to the potted plants. This investigation thus did not support the hypothesis stated in this thesis. The data in this investigation thus may indicate that plants with as diverse habitats as Mariscus congestus that are removed from their natural habitats display rapid changes in gas exchange characteristics in response to their new microclimates, with few ecotypic physiological characteristics of the old habitat being retained.
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Date Issued: 1992

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The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer

- Wright, Alan

Authors: Wright, Alan
Date: 1992
Subjects: Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4817 , http://hdl.handle.net/10962/d1005491 , Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
Description: The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
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Date Issued: 1992

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The attitudes and perceptions of secondary school pupils in Transkei towards geography: a case study of the Butterworth district

- Sarpong, Emmanuel

Authors: Sarpong, Emmanuel
Date: 1992
Subjects: Students, Black -- South Africa -- Attitudes Geography -- South Africa -- Transkei -- Study and teaching (Secondary)
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1425 , http://hdl.handle.net/10962/d1003306
Description: Considerable attention has in recent times been given to the attitudes of secondary school pupils towards Geography among black schools in South Africa. Many reasons account for this. It is partly because of the poor results and falling numbers of pupils in the discipline. Concern has also been expressed on the relevance of the Geography syllabus to the black pupils. Evidence suggests that these problems are evident in Transkei. The need therefore exists to assess pupils' attitudes towards Geography in Transkei. Arising from this background, this study sets out to assess the attitudes of secondary school pupils in Transkei towards Geography. Two hundred and thirty four pupils from eight urban and rural secondary schools in the Butterworth District of the Republic of Transkei were used in the study. Attitudes were measured in terms of "interest in Geography", "desire to study the discipline", "commitment to Geography" and the perceived relevance of the discipline. Through the use of techniques such as percentages, chi-square and principal component analysis - among others - for the analysis of the data, the following information emerged from the study: (1) Geography is generally perceived as being worthy of study; (2) Differences in responses were noted to result from a complex of factors which were grouped into home environmental factors and school environmental ones. (3) The major factor influencing attitudes towards Geography was noted to be home environmental conditions.In general pupils from lower income families expressed more positive views about the worth of Geography than those from the upper income families. From the above findings, it has been proposed that teachers and educational planners need to be made aware of these findings as they are important for classroom practice. It has also been recommended that there is a need to improve certain school practices such as taking pupils on Geography excursions more often as factors such as this were shown to improve pupils' attitudes towards the discipline.
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Date Issued: 1992

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