The early proterozoic Makganyene glacial event in South Africa : its implication in sequence stratigraphy interpretations, paleoenvironmental conditions and iron and manganese ore deposition
- Authors: Polteau, Stéphane
- Date: 2005
- Subjects: Geology, Stratigraphic -- South Africa -- Northern Cape Geochemistry -- South Africa -- Northern Cape Paleogeography -- South Africa -- Northern Cape Petrology -- South Africa -- Northern Cape Ore deposits -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5039 , http://hdl.handle.net/10962/d1007612
- Description: The Makganyene Formation forms the base of the Postmasburg Group in the Transvaal Supergroup in the Griqualand West Basin. It consists of diamictites, sandstones, banded iron-formations (BIFs), shales, siltstones and carbonates. It is generally accepted that the Makganyene Formation rests on an erosive regional unconformity throughout the Northern Cape Province. However this study demonstrates that this stratigraphic relationship is not universal, and conformable contacts have been observed. One of the principal aims of this study is to identify the nature of the Makganyene basal contact throughout the Griqualand West Basin. Intensive fieldwork was carried out from Prieska in the south, to Danielskuil in the north. In the Sishen and Hotazel areas, only borehole material was available to assess the stratigraphy. The Griquatown Fault Zone delimits the boundary between the deep basin and platform facies. The Koegas Subgroup is only present south of the Griquatown Fault Zone, where it pinches out. However, the transition Griquatown BIFs-Koegas Subgroup occurs in lacustrine deposits on the Ghaap platform (Beukes, 1983). The Griquatown Fault Zone represents the edge of the basin, which corresponds to a hinge rather than a fault zone. The Makganyene Formation rests with a conformable contact on the Koegas Subgroup south of the Griquatown Hinge Zone, and north of it the Makganyene Formation lies unconformably on the Asbestos Hills Subgroup. The Makganyene Formation displays lateral facies changes that reflect the paleogeography of the Griqualand West Basin, and the development of ice sheets/shelves. The Ghaap platform is characterised by coarse immature sand interbedded with the diamictites. The clasts in this area contain local Asbestos Hills material and no dropstones are present. Such settings are typical of sediments that are being deposited below a grounded ice mass. At the Griquatown Hinge Zone, the sandstone lenses are smaller, and the clasts consist of chert, of which a great number are striated and faceted. In the Matsap area, the presence of dropstones is strong evidence for the presence of a floating ice shelf that released its material by basal melting. Further south, the Makganyene Formation contains stromatolitic bioherms that only form if clastic contamination is minimal and therefore the ice that transported the detritus to the basin did not extend far into open sea conditions. The base of the Hotazel Formation also contains diamictite levels. Dropstones have been identified, implying a glacial origin. The Hotazel diamictites are interbedded with hyaloclastites and BIFs. The Makganyene glacial event, therefore, was not restricted to the Makganyene Formation, but also included the Ongeluk Formation, through to the base of the Hotazel Formation. Petrographic studies of the Makganyene Formation and the base of the Hotazel Formation reveal mineral assemblages that are diagnostic of early to late diagenetic crystallisation and of low-grade metamorphism not exceeding the very low green-schist facies. The facies identified display the same sense of basin deepening, from shallow high-energy Hotazel area on the Ghaap platform, to the deep basin in the Matsap area. Whole-rock geochemical analyses reveal that the elemental composition of the Makganyene Formation is very similar to that of the Asbestos Hills BIFs, which were the most important source of clastic detritus for the Makganyene Formation. However, minor amounts of carbonates of the Campbellrand Subgroup, as well as a felsic crustal input from the Archean granitoid basement, made contributions. On the Ghaap platform, the Makganyene diamictite is enriched in iron, calcium, and magnesium, while in the deeper parts of the basin the diamictites are enriched in detrital elements, such as titanium and aluminium, which occur in the fine clay component. The Hotazel diamictite displays a distinct mafic volcanic input, related to the extrusion of the Ongeluk basaltic andesites, which was incorporated in the glacial sediments. Sequence stratigraphy is based on the recognition of contacts separating the different systems tracts that compose a depositional sequence. However, because the basal contact of the Makganyene Formation has not been properly identified in previous work, no correct model has been proposed so far. Therefore correlations between the Griqualand West and the Transvaal basins, based on lithostratigraphic similarities and extrapolations of unconformities, have to be reviewed, especially since the publication of new radiometric ages contradict all previously proposed correlations. It is proposed here that the Transvaal Supergroup in the Griqualand West Basin represents a continuous depositional event that lasted about 200 Ma. The Makganyene glacial event occurred during changing conditions in the chemistries of the atmosphere and ocean, and in the continental configuration. A Snowball Earth event has been proposed as the causative process of such paleoenvironmental changes. However, evidence presented here of less dramatic glacial conditions, with areas of ice-free waters, implies an alternative to the Snowball Earth event. The paleoenvironmental changes are thought to represent a transition from an anaerobic to aerobic atmosphere, that was responsible for the global cooling of the surface of the Earth, Such a glacial event may have aided in the large-scale precipitation of iron and manganese in areas of intense upwellings.
- Full Text:
- Authors: Polteau, Stéphane
- Date: 2005
- Subjects: Geology, Stratigraphic -- South Africa -- Northern Cape Geochemistry -- South Africa -- Northern Cape Paleogeography -- South Africa -- Northern Cape Petrology -- South Africa -- Northern Cape Ore deposits -- South Africa -- Northern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5039 , http://hdl.handle.net/10962/d1007612
- Description: The Makganyene Formation forms the base of the Postmasburg Group in the Transvaal Supergroup in the Griqualand West Basin. It consists of diamictites, sandstones, banded iron-formations (BIFs), shales, siltstones and carbonates. It is generally accepted that the Makganyene Formation rests on an erosive regional unconformity throughout the Northern Cape Province. However this study demonstrates that this stratigraphic relationship is not universal, and conformable contacts have been observed. One of the principal aims of this study is to identify the nature of the Makganyene basal contact throughout the Griqualand West Basin. Intensive fieldwork was carried out from Prieska in the south, to Danielskuil in the north. In the Sishen and Hotazel areas, only borehole material was available to assess the stratigraphy. The Griquatown Fault Zone delimits the boundary between the deep basin and platform facies. The Koegas Subgroup is only present south of the Griquatown Fault Zone, where it pinches out. However, the transition Griquatown BIFs-Koegas Subgroup occurs in lacustrine deposits on the Ghaap platform (Beukes, 1983). The Griquatown Fault Zone represents the edge of the basin, which corresponds to a hinge rather than a fault zone. The Makganyene Formation rests with a conformable contact on the Koegas Subgroup south of the Griquatown Hinge Zone, and north of it the Makganyene Formation lies unconformably on the Asbestos Hills Subgroup. The Makganyene Formation displays lateral facies changes that reflect the paleogeography of the Griqualand West Basin, and the development of ice sheets/shelves. The Ghaap platform is characterised by coarse immature sand interbedded with the diamictites. The clasts in this area contain local Asbestos Hills material and no dropstones are present. Such settings are typical of sediments that are being deposited below a grounded ice mass. At the Griquatown Hinge Zone, the sandstone lenses are smaller, and the clasts consist of chert, of which a great number are striated and faceted. In the Matsap area, the presence of dropstones is strong evidence for the presence of a floating ice shelf that released its material by basal melting. Further south, the Makganyene Formation contains stromatolitic bioherms that only form if clastic contamination is minimal and therefore the ice that transported the detritus to the basin did not extend far into open sea conditions. The base of the Hotazel Formation also contains diamictite levels. Dropstones have been identified, implying a glacial origin. The Hotazel diamictites are interbedded with hyaloclastites and BIFs. The Makganyene glacial event, therefore, was not restricted to the Makganyene Formation, but also included the Ongeluk Formation, through to the base of the Hotazel Formation. Petrographic studies of the Makganyene Formation and the base of the Hotazel Formation reveal mineral assemblages that are diagnostic of early to late diagenetic crystallisation and of low-grade metamorphism not exceeding the very low green-schist facies. The facies identified display the same sense of basin deepening, from shallow high-energy Hotazel area on the Ghaap platform, to the deep basin in the Matsap area. Whole-rock geochemical analyses reveal that the elemental composition of the Makganyene Formation is very similar to that of the Asbestos Hills BIFs, which were the most important source of clastic detritus for the Makganyene Formation. However, minor amounts of carbonates of the Campbellrand Subgroup, as well as a felsic crustal input from the Archean granitoid basement, made contributions. On the Ghaap platform, the Makganyene diamictite is enriched in iron, calcium, and magnesium, while in the deeper parts of the basin the diamictites are enriched in detrital elements, such as titanium and aluminium, which occur in the fine clay component. The Hotazel diamictite displays a distinct mafic volcanic input, related to the extrusion of the Ongeluk basaltic andesites, which was incorporated in the glacial sediments. Sequence stratigraphy is based on the recognition of contacts separating the different systems tracts that compose a depositional sequence. However, because the basal contact of the Makganyene Formation has not been properly identified in previous work, no correct model has been proposed so far. Therefore correlations between the Griqualand West and the Transvaal basins, based on lithostratigraphic similarities and extrapolations of unconformities, have to be reviewed, especially since the publication of new radiometric ages contradict all previously proposed correlations. It is proposed here that the Transvaal Supergroup in the Griqualand West Basin represents a continuous depositional event that lasted about 200 Ma. The Makganyene glacial event occurred during changing conditions in the chemistries of the atmosphere and ocean, and in the continental configuration. A Snowball Earth event has been proposed as the causative process of such paleoenvironmental changes. However, evidence presented here of less dramatic glacial conditions, with areas of ice-free waters, implies an alternative to the Snowball Earth event. The paleoenvironmental changes are thought to represent a transition from an anaerobic to aerobic atmosphere, that was responsible for the global cooling of the surface of the Earth, Such a glacial event may have aided in the large-scale precipitation of iron and manganese in areas of intense upwellings.
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The effect of personalised adjustments to computer workstations on the efficiency and physical comfort of computer operators
- Authors: James, Genevieve
- Date: 2005
- Subjects: Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5112 , http://hdl.handle.net/10962/d1005190 , Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Description: The present study sought to investigate the effects of a Standard workstation, designed for “average” users, on an anthropometrically diverse sample of computer operators, and to assess whether physical and perceptual responses, as well as performance efficiency were dependent on stature. Further investigation assessed the influence of personalised adjustments to the Standard workstation, based on the anthropometric characteristics of the subjects, as well as the introduction of a custom-designed ‘floating’ wrist support, on subject responses. All subjects (n=30) were tested in each of the three workstations: Standard, Personalised and Wrist Support. For analysis of responses in the Standard workstation, subjects were divided into three groups depending on their stature: Short (<1650mm), Medium (1650mm to 1800mm), Tall (>1800mm). The musculoskeletal responses indicated that Tall subjects were forced to adopt the most awkward general body postures as a result of the low computer screen. However, the low screen allowed for the Short subjects to adopt the most natural general body postures, although levels of muscular activity in the upper trapezius suggest that the muscular load imposed on both Short and Tall subjects was significantly greater than that imposed on the Medium subjects. In addition, the Medium subjects’ perceptions of the Standard workstation dimensions support the fact that this workstation was better suited to users with “average” morphologies. The responses elicited in the Personalised and Wrist Support workstations were improved significantly when compared to the Standard workstation. Joint angles were more natural, upper trapezius EMG was reduced, standard of performance improved and perceptual responses indicated a diminished incidence of body and visual discomfort, as well as greater perceived satisfaction with these workstation dimensions. The improved physical responses suggest a decrease in the risk of developing cumulative trauma disorders. Although subjects were unaccustomed to the wrist support device, this workstation demonstrated a further reduction in the range of wrist angles, as well as a general positive attitude towards the concept.
- Full Text:
- Authors: James, Genevieve
- Date: 2005
- Subjects: Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5112 , http://hdl.handle.net/10962/d1005190 , Human engineering , Engineering design , Work environment , Microcomputer workstations -- Health aspects , Occupational diseases -- Prevention
- Description: The present study sought to investigate the effects of a Standard workstation, designed for “average” users, on an anthropometrically diverse sample of computer operators, and to assess whether physical and perceptual responses, as well as performance efficiency were dependent on stature. Further investigation assessed the influence of personalised adjustments to the Standard workstation, based on the anthropometric characteristics of the subjects, as well as the introduction of a custom-designed ‘floating’ wrist support, on subject responses. All subjects (n=30) were tested in each of the three workstations: Standard, Personalised and Wrist Support. For analysis of responses in the Standard workstation, subjects were divided into three groups depending on their stature: Short (<1650mm), Medium (1650mm to 1800mm), Tall (>1800mm). The musculoskeletal responses indicated that Tall subjects were forced to adopt the most awkward general body postures as a result of the low computer screen. However, the low screen allowed for the Short subjects to adopt the most natural general body postures, although levels of muscular activity in the upper trapezius suggest that the muscular load imposed on both Short and Tall subjects was significantly greater than that imposed on the Medium subjects. In addition, the Medium subjects’ perceptions of the Standard workstation dimensions support the fact that this workstation was better suited to users with “average” morphologies. The responses elicited in the Personalised and Wrist Support workstations were improved significantly when compared to the Standard workstation. Joint angles were more natural, upper trapezius EMG was reduced, standard of performance improved and perceptual responses indicated a diminished incidence of body and visual discomfort, as well as greater perceived satisfaction with these workstation dimensions. The improved physical responses suggest a decrease in the risk of developing cumulative trauma disorders. Although subjects were unaccustomed to the wrist support device, this workstation demonstrated a further reduction in the range of wrist angles, as well as a general positive attitude towards the concept.
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The effects of the invasive mussel mytilus galloprovincialis and human exploitation on the indigenous mussel Perna perna on the South Coast of South Africa
- Authors: Rius Viladomiu, Marc
- Date: 2005
- Subjects: Mussels -- South Africa , Perna -- South Africa , Mytilus galloprovincialis -- South Africa , Mytilidae -- South Africa , Biological invasions , Marine resources conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5684 , http://hdl.handle.net/10962/d1005370 , Mussels -- South Africa , Perna -- South Africa , Mytilus galloprovincialis -- South Africa , Mytilidae -- South Africa , Biological invasions , Marine resources conservation -- South Africa
- Description: In South Africa, the indigenous mussel Perna perna is threatened by both an invasive species and excessive human exploitation. The Mediterranean mussel Mytilus galloprovincialis is an invasive species that has been introduced to many parts of the world. In South Africa, this species arrived in the 1970s and spread rapidly along the west coast where today it is the dominant mussel species. Along the west coast, M. galloprovincialis is competitively superior in all aspects to the indigenous mussel species, and, as a result, has displaced some of them. On the south coast, M. galloprovincialis found more oligotrophic waters, higher species richness, and a stronger competitor in the indigenous mussel P. perna. The rate of spread of M. galloprovincialis along the south coast has decreased over the last 10 years and the present eastern limit of its distribution in South African is East London. On the south coast, M. galloprovincialis has not yet completely replaced P. perna; instead, the two exhibit spatial segregation, with P. perna dominating the low shore, M. galloprovincialis the high shore and an overlap zone between the two. An experiment on competition was carried out at one site on the south coast. The results showed that, on the low shore, P. perna is a more dominant competitor for space than M. galloprovincialis. Also byssus attachment of the two species differs, P. perna being much stronger than M. galloprovincialis, which suffers high mortality due to wave action on the low shore, especially in monospecific beds. As a result, mortality of M. galloprovincialis through wave action is reduced by the presence of P. perna, which seems to confer protection against dislodgement. However, in the absence of strong wave action, P. perna competitively excludes M. galloprovincialis. Human exploitation along 160 km of coast was examined by sampling mussel populations and using aerial surveys to determine where harvesters were distributed. Collectors did not seem to discriminate between species. The study has shown that higher abundances of mussels were found in protected or inaccessible sites, while in unprotected sites mussels were scarce. Coastal nature reserves are being proven to be effective in protecting mussel populations.
- Full Text:
- Authors: Rius Viladomiu, Marc
- Date: 2005
- Subjects: Mussels -- South Africa , Perna -- South Africa , Mytilus galloprovincialis -- South Africa , Mytilidae -- South Africa , Biological invasions , Marine resources conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5684 , http://hdl.handle.net/10962/d1005370 , Mussels -- South Africa , Perna -- South Africa , Mytilus galloprovincialis -- South Africa , Mytilidae -- South Africa , Biological invasions , Marine resources conservation -- South Africa
- Description: In South Africa, the indigenous mussel Perna perna is threatened by both an invasive species and excessive human exploitation. The Mediterranean mussel Mytilus galloprovincialis is an invasive species that has been introduced to many parts of the world. In South Africa, this species arrived in the 1970s and spread rapidly along the west coast where today it is the dominant mussel species. Along the west coast, M. galloprovincialis is competitively superior in all aspects to the indigenous mussel species, and, as a result, has displaced some of them. On the south coast, M. galloprovincialis found more oligotrophic waters, higher species richness, and a stronger competitor in the indigenous mussel P. perna. The rate of spread of M. galloprovincialis along the south coast has decreased over the last 10 years and the present eastern limit of its distribution in South African is East London. On the south coast, M. galloprovincialis has not yet completely replaced P. perna; instead, the two exhibit spatial segregation, with P. perna dominating the low shore, M. galloprovincialis the high shore and an overlap zone between the two. An experiment on competition was carried out at one site on the south coast. The results showed that, on the low shore, P. perna is a more dominant competitor for space than M. galloprovincialis. Also byssus attachment of the two species differs, P. perna being much stronger than M. galloprovincialis, which suffers high mortality due to wave action on the low shore, especially in monospecific beds. As a result, mortality of M. galloprovincialis through wave action is reduced by the presence of P. perna, which seems to confer protection against dislodgement. However, in the absence of strong wave action, P. perna competitively excludes M. galloprovincialis. Human exploitation along 160 km of coast was examined by sampling mussel populations and using aerial surveys to determine where harvesters were distributed. Collectors did not seem to discriminate between species. The study has shown that higher abundances of mussels were found in protected or inaccessible sites, while in unprotected sites mussels were scarce. Coastal nature reserves are being proven to be effective in protecting mussel populations.
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The evaluation of a multi-modal cognitive-behavioural approach to treating an adolescent with conduct disorder
- Authors: Mashalaba, Eugenia Dudu
- Date: 2005
- Subjects: Conduct disorders in adolescence , Aggressiveness in adolescence , Violence in children , Behavior disorders in children -- Treatment , Attention-deficit disorder in adolescence , Oppositional defiant disorder in adolescence , Cognitive therapy Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3014 , http://hdl.handle.net/10962/d1002523 , Conduct disorders in adolescence , Aggressiveness in adolescence , Violence in children , Behavior disorders in children -- Treatment , Attention-deficit disorder in adolescence , Oppositional defiant disorder in adolescence , Cognitive therapy Case studies
- Description: Conduct Disorder (CD) is a repetitive and persistent pattern of behaviour in which the basic rights of others or major age-appropriate societal norms or rules are violated. It is one of the most common problems in South African schools, particularly in those that are poverty-stricken. The child who participated in the study lived in the shelter that was for homeless and disadvantaged children. He attended at Amasango School where the majority of children in the shelter attended. There were many conduct-disordered children in the shelter and the school, particularly in the school. They disrupted classes making in difficult for teachers to carry out their education activities. The aim of this study was to draw on the standard procedures of the CBT in order to design interventions that would be effective in reducing aggressive behaviour in an adolescent who had CD Adolescent-Type and who lived at the shelter. This case study evaluated the effectiveness of a multi-modal CBT programme in a 16 year-old Black male who had been displaying aggressive behaviour for about a year. The treatment consisted of 23 sessions and included teacher counseling, contingency management, self-control and self-instructional training. The treatment was evaluated qualitatively by means of interviews with the child and teacher and quantitatively by means of repeated applications of behaviour checklists completed by the teacher. The results showed a decrease in the client's aggressive behaviour and an increase in prosocial behaviour. The client ultimately ceased from all aggressive behaviour towards his peers and this outcome was sustained during his last two months in therapy.
- Full Text:
- Authors: Mashalaba, Eugenia Dudu
- Date: 2005
- Subjects: Conduct disorders in adolescence , Aggressiveness in adolescence , Violence in children , Behavior disorders in children -- Treatment , Attention-deficit disorder in adolescence , Oppositional defiant disorder in adolescence , Cognitive therapy Case studies
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3014 , http://hdl.handle.net/10962/d1002523 , Conduct disorders in adolescence , Aggressiveness in adolescence , Violence in children , Behavior disorders in children -- Treatment , Attention-deficit disorder in adolescence , Oppositional defiant disorder in adolescence , Cognitive therapy Case studies
- Description: Conduct Disorder (CD) is a repetitive and persistent pattern of behaviour in which the basic rights of others or major age-appropriate societal norms or rules are violated. It is one of the most common problems in South African schools, particularly in those that are poverty-stricken. The child who participated in the study lived in the shelter that was for homeless and disadvantaged children. He attended at Amasango School where the majority of children in the shelter attended. There were many conduct-disordered children in the shelter and the school, particularly in the school. They disrupted classes making in difficult for teachers to carry out their education activities. The aim of this study was to draw on the standard procedures of the CBT in order to design interventions that would be effective in reducing aggressive behaviour in an adolescent who had CD Adolescent-Type and who lived at the shelter. This case study evaluated the effectiveness of a multi-modal CBT programme in a 16 year-old Black male who had been displaying aggressive behaviour for about a year. The treatment consisted of 23 sessions and included teacher counseling, contingency management, self-control and self-instructional training. The treatment was evaluated qualitatively by means of interviews with the child and teacher and quantitatively by means of repeated applications of behaviour checklists completed by the teacher. The results showed a decrease in the client's aggressive behaviour and an increase in prosocial behaviour. The client ultimately ceased from all aggressive behaviour towards his peers and this outcome was sustained during his last two months in therapy.
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The exploration of the impact of state ownership on Uganda's New Vision Newspaper's social role
- Authors: Wasswa, John Baptist
- Date: 2005
- Subjects: New Vision (Uganda) , Government and the press -- Uganda , Press and politics -- Uganda , Newspaper publishing -- Uganda
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3493 , http://hdl.handle.net/10962/d1002948 , New Vision (Uganda) , Government and the press -- Uganda , Press and politics -- Uganda , Newspaper publishing -- Uganda
- Description: The global trends of democratisation and privatisation that swept much of the developing world in the 1980s and 1990s led to significant changes in the conceptualisation, organisation and performance of the media. In Africa democratisation attained a new meaning with associated processes of liberalisation of broadcasting to end the monopoly of broadcasting by the state. The private media of the liberalised market is increasingly putting the public media system, both broadcast and print, under serious competition, and forcing them to adjust to changing circumstances. The New Vision newspaper in Uganda is one such public service media organisations that are owned by the state and yet have to compete in the new more democratic and liberalised environment. This study set out to explore the extent to which state-ownership impacts on The New Vision’s social role. Using both qualitative and quantitative methods of date collection, I have established the that although The New Vision is a public service medium for which government remains the major source of news, it does not in most cases give the state more or preferentially prominent coverage at the expense of other interest groups in society. On contrary, basing of the amount of coverage of civil society I established that The New Vision enabled the various groups public sphere to interact. The newspaper to an extent also plays the democratic role of monitoring government although there was little evidence of monitoring of corporate abuse. The nature of The New Vision Statute, and the global trends that have changed the conduct of official and private business, have rendered the theories on the 1980s’ development media theories increasingly inapplicable, forcing The New Vision to develop its own version of development journalism that is socially relevant. The study recommends that whereas much of The New Vision Statute is progressive, sections of it should be removed to protect the newspaper from being manipulated by government functionaries, if the it is to continue enabling the public sphere. The newspaper should also increase its monitoring of corporate abuse, and make internal reforms to improve the coverage of development related issues.
- Full Text:
- Authors: Wasswa, John Baptist
- Date: 2005
- Subjects: New Vision (Uganda) , Government and the press -- Uganda , Press and politics -- Uganda , Newspaper publishing -- Uganda
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3493 , http://hdl.handle.net/10962/d1002948 , New Vision (Uganda) , Government and the press -- Uganda , Press and politics -- Uganda , Newspaper publishing -- Uganda
- Description: The global trends of democratisation and privatisation that swept much of the developing world in the 1980s and 1990s led to significant changes in the conceptualisation, organisation and performance of the media. In Africa democratisation attained a new meaning with associated processes of liberalisation of broadcasting to end the monopoly of broadcasting by the state. The private media of the liberalised market is increasingly putting the public media system, both broadcast and print, under serious competition, and forcing them to adjust to changing circumstances. The New Vision newspaper in Uganda is one such public service media organisations that are owned by the state and yet have to compete in the new more democratic and liberalised environment. This study set out to explore the extent to which state-ownership impacts on The New Vision’s social role. Using both qualitative and quantitative methods of date collection, I have established the that although The New Vision is a public service medium for which government remains the major source of news, it does not in most cases give the state more or preferentially prominent coverage at the expense of other interest groups in society. On contrary, basing of the amount of coverage of civil society I established that The New Vision enabled the various groups public sphere to interact. The newspaper to an extent also plays the democratic role of monitoring government although there was little evidence of monitoring of corporate abuse. The nature of The New Vision Statute, and the global trends that have changed the conduct of official and private business, have rendered the theories on the 1980s’ development media theories increasingly inapplicable, forcing The New Vision to develop its own version of development journalism that is socially relevant. The study recommends that whereas much of The New Vision Statute is progressive, sections of it should be removed to protect the newspaper from being manipulated by government functionaries, if the it is to continue enabling the public sphere. The newspaper should also increase its monitoring of corporate abuse, and make internal reforms to improve the coverage of development related issues.
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The feeding ecology and habitat use of lions reintroduced to small, enclosed reserves in the Eastern Cape Province, South Africa
- Authors: Rapson, Jackie Anne
- Date: 2005
- Subjects: Lion -- Food -- South Africa -- Eastern Cape , Lion -- Behavior -- South Africa -- Eastern Cape , Predation (Biology) , Lion -- Nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5938 , http://hdl.handle.net/10962/d1018268
- Description: Lions have recently been introduced to a number of small (<300km²), enclosed reserves in the Eastern Cape Province as a draw-card for tourists. However, there have been few studies of lion behaviour or predator prey interactions within small reserves. Thus the aim of this study is to contribute towards a better understanding of the effects of space on diet and habitat use of re-introduced lions. The research was conducted at two small private reserves, Shamwari and Kwandwe. Kills were mostly large (55%, >120kg), adult (41%) and male (39%) and the five most commonly killed species (kudu, black wildebeest, warthog, bushbuck and Blesbuck) comprised 67.9% of all kills and 67.8% of total biomass consumed. In an attempt to overcome the problem of gaps in the kill lists, a subset of data, which excluded kills more than five days apart, was analyzed and this gave similar results to analysis of the full kill lists. Mean daily intake rates varied annually between 2.26 and 5.23kg.FEQ⁻¹ for the full data set and 4.53 and 1 0.46kg.FEQ⁻¹ for the subset. The difference between estimated (calculated using daily intake rates of 5 and 7.12kg.FEQ⁻¹) and observed offtake for each ungulate species reflected the preference ratings for that species. Analysis of bone marrow indicated that: lions killed ungulates in moderate to good condition; condition of culled animals was lower than that of kills; distal bones could be used in analyses; and that that bones exposed to the environment for at least a week could be used to analyze condition of prey. Home ranges and activity centers ranged from 21.42km² to 73.27km² and 2.7lkm² to 17.47km² respectively, which was smaller than expected from previous studies. Although, lions at K wandwe and Shan1wari preferred different vegetation types, at both reserves they generally occupied areas that were structurally similar to what has previously been reported. Continuous monitoring and analyses of diet, including condition of the prey, and habitat use will provide reserve managers with some of the necessary information to enable them to effectively manage their lion populations and to predict and minimize potential problems.
- Full Text:
- Authors: Rapson, Jackie Anne
- Date: 2005
- Subjects: Lion -- Food -- South Africa -- Eastern Cape , Lion -- Behavior -- South Africa -- Eastern Cape , Predation (Biology) , Lion -- Nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5938 , http://hdl.handle.net/10962/d1018268
- Description: Lions have recently been introduced to a number of small (<300km²), enclosed reserves in the Eastern Cape Province as a draw-card for tourists. However, there have been few studies of lion behaviour or predator prey interactions within small reserves. Thus the aim of this study is to contribute towards a better understanding of the effects of space on diet and habitat use of re-introduced lions. The research was conducted at two small private reserves, Shamwari and Kwandwe. Kills were mostly large (55%, >120kg), adult (41%) and male (39%) and the five most commonly killed species (kudu, black wildebeest, warthog, bushbuck and Blesbuck) comprised 67.9% of all kills and 67.8% of total biomass consumed. In an attempt to overcome the problem of gaps in the kill lists, a subset of data, which excluded kills more than five days apart, was analyzed and this gave similar results to analysis of the full kill lists. Mean daily intake rates varied annually between 2.26 and 5.23kg.FEQ⁻¹ for the full data set and 4.53 and 1 0.46kg.FEQ⁻¹ for the subset. The difference between estimated (calculated using daily intake rates of 5 and 7.12kg.FEQ⁻¹) and observed offtake for each ungulate species reflected the preference ratings for that species. Analysis of bone marrow indicated that: lions killed ungulates in moderate to good condition; condition of culled animals was lower than that of kills; distal bones could be used in analyses; and that that bones exposed to the environment for at least a week could be used to analyze condition of prey. Home ranges and activity centers ranged from 21.42km² to 73.27km² and 2.7lkm² to 17.47km² respectively, which was smaller than expected from previous studies. Although, lions at K wandwe and Shan1wari preferred different vegetation types, at both reserves they generally occupied areas that were structurally similar to what has previously been reported. Continuous monitoring and analyses of diet, including condition of the prey, and habitat use will provide reserve managers with some of the necessary information to enable them to effectively manage their lion populations and to predict and minimize potential problems.
- Full Text:
The feeding ecology, habitat selection and hunting behaviour of re-introduced cheetah on Kwandwe Private Game Reserve, Eastern Cape Province
- Authors: Bissett, Charlene
- Date: 2005
- Subjects: Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5698 , http://hdl.handle.net/10962/d1005384 , Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Description: The re-introduction of cheetah onto small reserves in the Eastern Cape Province has created the opportunity to study this species in an environment (Valley Bushveld) in which it has not previously been studied and which is quite different from the less wooded habitats in which previous studies have occurred. Thus the aim of this study is to add to the growing number of studies of cheetah in more wooded habitats and to contribute a better understanding of the level of specialization or adaptability in space use, habitat selection, diet and hunting behaviour that the cheetah possesses. The research was conducted on Kwandwe Private Game Reserve from February 2003 to August 2004. Direct observations, scat analysis and continuous observations were used to avoid bias towards large sized prey found when only using direct observations to study diet. The cheetah killed 15 species and four of the five most important prey species (kudu, springbok, grey duiker and bushbuck) were hunted according to their abundance on the reserve, while impala, the fifth most important prey species, was avoided (i.e. preference index less than one) by the cheetah. The cheetah’s main prey was medium sized ungulates, although the three male coalition killed larger prey than females and females with cubs. The daily food intake per cheetah per day was calculated to range from 5.3kg/cheetah/day for the coalition to 8kg/cheetah/day for a solitary female. Home range areas ranged from 11.1 km² for female cheetah with cubs in a den to 65.6 km² for single female cheetah and core areas ranged from 6 km² for the three male coalition to 26.5 km² for independent cubs. Habitat selection by cheetah on Kwandwe varied between the social groups depending on their susceptibility to predation by lions, their need for cover and need for water, and was similar to what has been previously reported. The home range of the coalition incorporated the most open vegetation type (karroid shrubland) with surrounding denser vegetation, while females occupied areas of denser vegetation. Activity patterns and hunting behaviour varied between different cheetah social groups with female cheetah being more active during day light hours compared to males which made 38% of their kills after dark. The average chase distances for the various cheetah groups varied considerably, and the chase distance for successful hunts was longer than for unsuccessful for all groups except single female cheetah. The percentage of kills’ kleptoparasitised on Kwandwe was very low compared to other studies possibly due to the low density of direct competitors, which in turn lead to longer mean kill retention times. These results suggest that cheetah are more adaptable than previously thought and this adaptability may have important implications for their conservation.
- Full Text:
- Authors: Bissett, Charlene
- Date: 2005
- Subjects: Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5698 , http://hdl.handle.net/10962/d1005384 , Kwandwe Game Reserve (South Africa) , Cheetah -- Behavior -- South Africa -- Eastern Cape , Cheetah -- Nutrition -- South Africa -- Eastern Cape , Cheetah -- South Africa -- Eastern Cape
- Description: The re-introduction of cheetah onto small reserves in the Eastern Cape Province has created the opportunity to study this species in an environment (Valley Bushveld) in which it has not previously been studied and which is quite different from the less wooded habitats in which previous studies have occurred. Thus the aim of this study is to add to the growing number of studies of cheetah in more wooded habitats and to contribute a better understanding of the level of specialization or adaptability in space use, habitat selection, diet and hunting behaviour that the cheetah possesses. The research was conducted on Kwandwe Private Game Reserve from February 2003 to August 2004. Direct observations, scat analysis and continuous observations were used to avoid bias towards large sized prey found when only using direct observations to study diet. The cheetah killed 15 species and four of the five most important prey species (kudu, springbok, grey duiker and bushbuck) were hunted according to their abundance on the reserve, while impala, the fifth most important prey species, was avoided (i.e. preference index less than one) by the cheetah. The cheetah’s main prey was medium sized ungulates, although the three male coalition killed larger prey than females and females with cubs. The daily food intake per cheetah per day was calculated to range from 5.3kg/cheetah/day for the coalition to 8kg/cheetah/day for a solitary female. Home range areas ranged from 11.1 km² for female cheetah with cubs in a den to 65.6 km² for single female cheetah and core areas ranged from 6 km² for the three male coalition to 26.5 km² for independent cubs. Habitat selection by cheetah on Kwandwe varied between the social groups depending on their susceptibility to predation by lions, their need for cover and need for water, and was similar to what has been previously reported. The home range of the coalition incorporated the most open vegetation type (karroid shrubland) with surrounding denser vegetation, while females occupied areas of denser vegetation. Activity patterns and hunting behaviour varied between different cheetah social groups with female cheetah being more active during day light hours compared to males which made 38% of their kills after dark. The average chase distances for the various cheetah groups varied considerably, and the chase distance for successful hunts was longer than for unsuccessful for all groups except single female cheetah. The percentage of kills’ kleptoparasitised on Kwandwe was very low compared to other studies possibly due to the low density of direct competitors, which in turn lead to longer mean kill retention times. These results suggest that cheetah are more adaptable than previously thought and this adaptability may have important implications for their conservation.
- Full Text:
The Grameen Bank model of microcredit and its relevance for South Africa
- Authors: Akpan, Iniobong Wilson
- Date: 2005
- Subjects: Grameen Bank , Microfinance -- South Africa , Microfinance -- Bangladesh , Credit -- Management , Risk management , Poor -- Finance, Personal , South Africa -- Economic conditions , Bangladesh -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:980 , http://hdl.handle.net/10962/d1002714 , Grameen Bank , Microfinance -- South Africa , Microfinance -- Bangladesh , Credit -- Management , Risk management , Poor -- Finance, Personal , South Africa -- Economic conditions , Bangladesh -- Economic conditions
- Description: Among the reasons for financial exclusion is the fact that the poor, being largely illiterate and unemployed, are traditionally perceived as ‘bad credit risks’. This is the dominant perception of the poor in the formal credit markets – a perception that also exists in the microcredit sector. In other words, while information asymmetry is a recognized problem in lender-borrower relationships, lenders consider the problem particularly severe when they contemplate doing business with the poor. A contrasting paradigm, such as the one adopted by Grameen Bank of Bangladesh, views the poor as possessing economic potentials that have not been tapped – that is, as ‘good credit risks’. Grameen Bank’s microcredit features appear to have successfully mitigated the problems of information asymmetry and, to a large extent, made it possible for the poor to access microenterprise credit. Using the Grameen Bank model as a benchmark, this study examined the lending features of private sector microlenders in South Africa and those of KhulaStart (credit) scheme. The aim was to identify how the lending features affect microenterprise credit access. Primary data were obtained through interviews, while relevant secondary data were also used in the study. A key finding of the study was that while the Khulastart scheme was, like Grameencredit, targeted at the poor, the method of its delivery appeared diluted or unduly influenced by the conventional (private sector) paradigm that pre-classifies people as ‘good’ or ‘bad’ credit risks. As a result, the scheme was not robust enough to support microenterprise credit access. This has consequences for job-creation and poverty reduction. Based on the findings, the study maintains that a realistic broadening of microenterprise credit access will not occur unless there is a fundamental paradigm shift in microcredit practices, and unless measures designed to mitigate information asymmetries are sensitive to the historical, economic and sociocultural realities of the South African poor.
- Full Text:
- Authors: Akpan, Iniobong Wilson
- Date: 2005
- Subjects: Grameen Bank , Microfinance -- South Africa , Microfinance -- Bangladesh , Credit -- Management , Risk management , Poor -- Finance, Personal , South Africa -- Economic conditions , Bangladesh -- Economic conditions
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:980 , http://hdl.handle.net/10962/d1002714 , Grameen Bank , Microfinance -- South Africa , Microfinance -- Bangladesh , Credit -- Management , Risk management , Poor -- Finance, Personal , South Africa -- Economic conditions , Bangladesh -- Economic conditions
- Description: Among the reasons for financial exclusion is the fact that the poor, being largely illiterate and unemployed, are traditionally perceived as ‘bad credit risks’. This is the dominant perception of the poor in the formal credit markets – a perception that also exists in the microcredit sector. In other words, while information asymmetry is a recognized problem in lender-borrower relationships, lenders consider the problem particularly severe when they contemplate doing business with the poor. A contrasting paradigm, such as the one adopted by Grameen Bank of Bangladesh, views the poor as possessing economic potentials that have not been tapped – that is, as ‘good credit risks’. Grameen Bank’s microcredit features appear to have successfully mitigated the problems of information asymmetry and, to a large extent, made it possible for the poor to access microenterprise credit. Using the Grameen Bank model as a benchmark, this study examined the lending features of private sector microlenders in South Africa and those of KhulaStart (credit) scheme. The aim was to identify how the lending features affect microenterprise credit access. Primary data were obtained through interviews, while relevant secondary data were also used in the study. A key finding of the study was that while the Khulastart scheme was, like Grameencredit, targeted at the poor, the method of its delivery appeared diluted or unduly influenced by the conventional (private sector) paradigm that pre-classifies people as ‘good’ or ‘bad’ credit risks. As a result, the scheme was not robust enough to support microenterprise credit access. This has consequences for job-creation and poverty reduction. Based on the findings, the study maintains that a realistic broadening of microenterprise credit access will not occur unless there is a fundamental paradigm shift in microcredit practices, and unless measures designed to mitigate information asymmetries are sensitive to the historical, economic and sociocultural realities of the South African poor.
- Full Text:
The historiographical development of the concept "mfecane" and the writing of early Southern African history, from the 1820s to 1920s
- Authors: Richner, Jürg Emile
- Date: 2005
- Subjects: South Africa -- History , South Africa -- Historiography , Bantu-speaking peoples -- Migrations , Africa, Southern -- History -- Mfecane period, 1816-ca. 1840
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2554 , http://hdl.handle.net/10962/d1002406 , South Africa -- History , South Africa -- Historiography , Bantu-speaking peoples -- Migrations , Africa, Southern -- History -- Mfecane period, 1816-ca. 1840
- Description: The mfecane was for most of the twentieth century regarded as a historical certainty for the South African public and the Apartheid government, as well as for historians here and world-wide. The mfecane had achieved the permanence of a paradigm and a dominant discourse, as it was accepted equally by settler, liberal, Afrikaner, Africanist and Neo-Marxist historians. This certainty was shaken when Cobbing’s mfecane critique appeared in 1988, with which I concur. This study examines how mfecane history was written from the first published articles in mid-1823 until Walker coined the concept mfecane in 1928. This thesis undertakes a journey through a host of published works, books, pamphlets and articles in journals, magazines and newspapers, from which a number of conclusions emerge. The mfecane narrative was developed over a period of a hundred years in the English language by almost exclusively white, English-speaking male amateur historians and ethnographers. Their occupations, age, ideology and level of education differed markedly, but they shared one European ideological value, the discourse of the European “Image of Africa”, which regarded Africans as the negative Other of their own positively perceived society. This was a culturallyshared view of Africans, which formed the baggage in the mind of all writers examined, and accounts for the mfecane narrative’s negative attitude towards Africans. Furthermore, mfecane history was influenced by racism and the use of literary devices such as the gothic novel and the romance. Authors writing in the 1823 to 1846 period on events which had taken place in the “blank space” beyond the Cape Colony, which most of them had never visited, laid the basis for the mfecane narrative. It constituted a set of geographical or ethnically focused, separate accounts. These separate accounts focused on the themes of Shaka’s creation of the Zulu state, including his expulsion of several chiefdoms; his depopulation of Natal and the flight of the Fingo to the Transkei; the path of destruction of the Hlubi and Ngwane during their flight from Natal via the greater Caledon Valley area to the Transkei; the incorporation of the Kololo and other Sotho chiefdoms into the Mantatees - due to pressure from the invaders from Natal - who subsequently laid waste the Free State and Transvaal as far as Dithakong, where they were defeated; the further depopulation of the Transvaal by the Ndebele during their escape from Shaka; the flight of Moshoeshoe and his people to Thaba Bosiu where he built up the Sotho state, with Moshoeshoe being the only positive figure in this history. This multi-narrative was thereafter repeated without any critical thought by all authors examined until in 1885 Theal created a Zulu-centric, geographically integrated mfecane narrative whereby he integrated the previously separate accounts into one coherent whole - a whole which was so much more than the sum of its parts, but so far without a defining name. That was provided by Walker in 1928 when he coined the Xhosa neologism, mfecane. The Theal, Cory and Walker racist mfecane was thus bequeathed as the mfecane to the rest of the twentieth century.
- Full Text:
- Authors: Richner, Jürg Emile
- Date: 2005
- Subjects: South Africa -- History , South Africa -- Historiography , Bantu-speaking peoples -- Migrations , Africa, Southern -- History -- Mfecane period, 1816-ca. 1840
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2554 , http://hdl.handle.net/10962/d1002406 , South Africa -- History , South Africa -- Historiography , Bantu-speaking peoples -- Migrations , Africa, Southern -- History -- Mfecane period, 1816-ca. 1840
- Description: The mfecane was for most of the twentieth century regarded as a historical certainty for the South African public and the Apartheid government, as well as for historians here and world-wide. The mfecane had achieved the permanence of a paradigm and a dominant discourse, as it was accepted equally by settler, liberal, Afrikaner, Africanist and Neo-Marxist historians. This certainty was shaken when Cobbing’s mfecane critique appeared in 1988, with which I concur. This study examines how mfecane history was written from the first published articles in mid-1823 until Walker coined the concept mfecane in 1928. This thesis undertakes a journey through a host of published works, books, pamphlets and articles in journals, magazines and newspapers, from which a number of conclusions emerge. The mfecane narrative was developed over a period of a hundred years in the English language by almost exclusively white, English-speaking male amateur historians and ethnographers. Their occupations, age, ideology and level of education differed markedly, but they shared one European ideological value, the discourse of the European “Image of Africa”, which regarded Africans as the negative Other of their own positively perceived society. This was a culturallyshared view of Africans, which formed the baggage in the mind of all writers examined, and accounts for the mfecane narrative’s negative attitude towards Africans. Furthermore, mfecane history was influenced by racism and the use of literary devices such as the gothic novel and the romance. Authors writing in the 1823 to 1846 period on events which had taken place in the “blank space” beyond the Cape Colony, which most of them had never visited, laid the basis for the mfecane narrative. It constituted a set of geographical or ethnically focused, separate accounts. These separate accounts focused on the themes of Shaka’s creation of the Zulu state, including his expulsion of several chiefdoms; his depopulation of Natal and the flight of the Fingo to the Transkei; the path of destruction of the Hlubi and Ngwane during their flight from Natal via the greater Caledon Valley area to the Transkei; the incorporation of the Kololo and other Sotho chiefdoms into the Mantatees - due to pressure from the invaders from Natal - who subsequently laid waste the Free State and Transvaal as far as Dithakong, where they were defeated; the further depopulation of the Transvaal by the Ndebele during their escape from Shaka; the flight of Moshoeshoe and his people to Thaba Bosiu where he built up the Sotho state, with Moshoeshoe being the only positive figure in this history. This multi-narrative was thereafter repeated without any critical thought by all authors examined until in 1885 Theal created a Zulu-centric, geographically integrated mfecane narrative whereby he integrated the previously separate accounts into one coherent whole - a whole which was so much more than the sum of its parts, but so far without a defining name. That was provided by Walker in 1928 when he coined the Xhosa neologism, mfecane. The Theal, Cory and Walker racist mfecane was thus bequeathed as the mfecane to the rest of the twentieth century.
- Full Text:
The labour market drop-out rate : a new approach to estimating the returns to government investment in higher education : the case for marine science in South Africa
- Authors: Grootes, Pieter Brian
- Date: 2005
- Subjects: Labor market Marine scientists -- South Africa Education -- Economic aspects -- South Africa Higher education and state -- South Africa Education -- Social aspects Human capital -- South Africa Education, Higher -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:950 , http://hdl.handle.net/10962/d1002684
- Description: The private and social returns to education literature share the same conclusion: that education is beneficial for both the individual and society. However, the theoretical underpinnings are flawed as the literature does not account for the main feature that leads to the acquisition of education: the private demand for education. An understanding of the factors that motivate the individual to invest in education would lead to a deeper insight as to why both private and social returns to education exist, and would provide a clearer framework on which to base the government funding of education. This thesis provides a first attempt at filling this gap by introducing a method of estimating the returns to government investment in education, which is labelled the ‘labour market drop-out rate approach’. The approach focuses on the social return to education, not in terms of graduate earnings, but in terms of the interaction of the graduate with the economy. The approach introduces a measure of expertise utilisation, based on the premise that there is no social return to an individual acquiring education if he or she does not utilise the acquired knowledge base on entering the labour market. The approach is tested using the labour market for marine scientists in South Africa as a case study. In this case the private demand for education is found to be heavily influenced by the provision of student bursaries from the National Research Foundation, with a resulting estimate of the social return to a degree in marine science being a mere 20% to 25%. Owing to this, a new approach to government investment in marine science is introduced, that of graduate contribution schemes. Of broader significance is the ease of application of this approach, it may be adopted to analyse any funding programme in which a government may decide to invest. As such, the labour market drop-out rate provides an extension to the returns to education literature through its theoretical dealings of the private demand for education, as well as a practical tool which government agencies can use to evaluate the efficacy of any government funding of education.
- Full Text:
- Authors: Grootes, Pieter Brian
- Date: 2005
- Subjects: Labor market Marine scientists -- South Africa Education -- Economic aspects -- South Africa Higher education and state -- South Africa Education -- Social aspects Human capital -- South Africa Education, Higher -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:950 , http://hdl.handle.net/10962/d1002684
- Description: The private and social returns to education literature share the same conclusion: that education is beneficial for both the individual and society. However, the theoretical underpinnings are flawed as the literature does not account for the main feature that leads to the acquisition of education: the private demand for education. An understanding of the factors that motivate the individual to invest in education would lead to a deeper insight as to why both private and social returns to education exist, and would provide a clearer framework on which to base the government funding of education. This thesis provides a first attempt at filling this gap by introducing a method of estimating the returns to government investment in education, which is labelled the ‘labour market drop-out rate approach’. The approach focuses on the social return to education, not in terms of graduate earnings, but in terms of the interaction of the graduate with the economy. The approach introduces a measure of expertise utilisation, based on the premise that there is no social return to an individual acquiring education if he or she does not utilise the acquired knowledge base on entering the labour market. The approach is tested using the labour market for marine scientists in South Africa as a case study. In this case the private demand for education is found to be heavily influenced by the provision of student bursaries from the National Research Foundation, with a resulting estimate of the social return to a degree in marine science being a mere 20% to 25%. Owing to this, a new approach to government investment in marine science is introduced, that of graduate contribution schemes. Of broader significance is the ease of application of this approach, it may be adopted to analyse any funding programme in which a government may decide to invest. As such, the labour market drop-out rate provides an extension to the returns to education literature through its theoretical dealings of the private demand for education, as well as a practical tool which government agencies can use to evaluate the efficacy of any government funding of education.
- Full Text:
The life history patterns of the polychaete, Terebrasabella heterouncinata, a pest of cultured abalone
- Authors: Simon, Carol Anne
- Date: 2005
- Subjects: Polychaeta -- Physiology Sabellidae -- Physiology Abalones -- Diseases Polychaeta -- Reproduction Sabellidae -- Reproduction Abalone culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5336 , http://hdl.handle.net/10962/d1005632
- Description: Terebrasabella heterouncinata is a small K-selected sabellid polychaete. It is a simultaneous hermaphrodite with a semi-continuous mode of reproduction, producing relatively few large eggs that are brooded within the parental burrow until the larvae emerge, to settle on the growing edge of the abalone shell. Despite its low fecundity, this worm has become problematic on abalone farms in South Africa. The present study was conducted to gain an understanding of the life history patterns of T. helerouncinata to determine how they contributed to the success of these worms under altered conditions. This study demonstrated that conditions prevalent on abalone farms were conducive to enhancing the reproductive success of this worm, and suggests that larger, more fecund worms may have been selected for in the decade that these worms have been present on the farms. Increased nutrient availability, and possibly the increased stability of the farm environment relative to its natural environment, has led to a 1.5-fold increase in the average size of the worms. Body size was found to be positively correlated with brood size, and this resulted in worms on farms brooding 3 to 4.5 times more offspring at a time than worms from wild abalone. The ability to increase the number of eggs produced at a time may have been limited by the fact that these worms have only two ovaries. Thus, the increase in fecundity may have been related primarily to the increase in the rate at which the eggs were laid by the worms on the farms, and the increase in the coelomic space available for the storage of these rapidly developing eggs. The ability to increase the rate at which oocytes develop may be related to the vitellogenic mechanisms employed by these worms. Vitellogenic oocytes are able to incorporate high molecular weight yolk precursors from the surrounding coelomic fluid through endocytotic activity. This may allow the oocytes to increase the rate at which they incorporate yolk material under conditions of nutrient enrichment. The increase in fecundity did not occur at the expense of offspring size and, presumably, quality. The increased reproductive output on the farms was compounded by a proportionate increase in the number of reproducing worms within the population. In addition, these worms are long-lived (worms from farmed abalone reached a maximum age of approximately 40 months) and exhibit negligible senescence. Thus, their reproductive output did not change significantly with an increase in age. Furthermore, the proportion of the reproductive worms did not decrease with an increase in age. Thus, within the age range tested, worms of all ages have the potential to make equal contributions to population growth. While diet and abalone stocking density could not be identified as having a significant effect on reproductive output and infestation rate under intensive culture conditions, it was demonstrated that in a naïve abalone population, the total intensity of infestation increased exponentially with time. This increase may be a consequence of an increase in fertilisation success. These worms continuously produce entaquasperm that are released into the water column. The sperm are collected by other individuals that then store the sperm in a single spermatheca. The ability to store sperm relieves individuals of a dependence on the synchronisation of spawning of eggs and sperm. As the population size and density increases, there could be more individuals releasing sperm into the water column, resulting in a continuous supply of sperm. The increased production of eggs would therefore not be constrained by a lack of sperm. The stored sperm are released into the brood chamber to fertilise eggs as they are laid, and this would probably increase the fertilisation success in the species. This study also provides evidence to suggest that reproduction in this worm has a seasonal component. Future studies should concentrate on measuring fertilisation success in greater detail, measuring the effect of season on reproduction, determining whether there are genetic differences between worms on farmed and wild abalone and determining whether wild worms have similar life-spans and age-related fecundity as worms on farms.
- Full Text:
- Authors: Simon, Carol Anne
- Date: 2005
- Subjects: Polychaeta -- Physiology Sabellidae -- Physiology Abalones -- Diseases Polychaeta -- Reproduction Sabellidae -- Reproduction Abalone culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5336 , http://hdl.handle.net/10962/d1005632
- Description: Terebrasabella heterouncinata is a small K-selected sabellid polychaete. It is a simultaneous hermaphrodite with a semi-continuous mode of reproduction, producing relatively few large eggs that are brooded within the parental burrow until the larvae emerge, to settle on the growing edge of the abalone shell. Despite its low fecundity, this worm has become problematic on abalone farms in South Africa. The present study was conducted to gain an understanding of the life history patterns of T. helerouncinata to determine how they contributed to the success of these worms under altered conditions. This study demonstrated that conditions prevalent on abalone farms were conducive to enhancing the reproductive success of this worm, and suggests that larger, more fecund worms may have been selected for in the decade that these worms have been present on the farms. Increased nutrient availability, and possibly the increased stability of the farm environment relative to its natural environment, has led to a 1.5-fold increase in the average size of the worms. Body size was found to be positively correlated with brood size, and this resulted in worms on farms brooding 3 to 4.5 times more offspring at a time than worms from wild abalone. The ability to increase the number of eggs produced at a time may have been limited by the fact that these worms have only two ovaries. Thus, the increase in fecundity may have been related primarily to the increase in the rate at which the eggs were laid by the worms on the farms, and the increase in the coelomic space available for the storage of these rapidly developing eggs. The ability to increase the rate at which oocytes develop may be related to the vitellogenic mechanisms employed by these worms. Vitellogenic oocytes are able to incorporate high molecular weight yolk precursors from the surrounding coelomic fluid through endocytotic activity. This may allow the oocytes to increase the rate at which they incorporate yolk material under conditions of nutrient enrichment. The increase in fecundity did not occur at the expense of offspring size and, presumably, quality. The increased reproductive output on the farms was compounded by a proportionate increase in the number of reproducing worms within the population. In addition, these worms are long-lived (worms from farmed abalone reached a maximum age of approximately 40 months) and exhibit negligible senescence. Thus, their reproductive output did not change significantly with an increase in age. Furthermore, the proportion of the reproductive worms did not decrease with an increase in age. Thus, within the age range tested, worms of all ages have the potential to make equal contributions to population growth. While diet and abalone stocking density could not be identified as having a significant effect on reproductive output and infestation rate under intensive culture conditions, it was demonstrated that in a naïve abalone population, the total intensity of infestation increased exponentially with time. This increase may be a consequence of an increase in fertilisation success. These worms continuously produce entaquasperm that are released into the water column. The sperm are collected by other individuals that then store the sperm in a single spermatheca. The ability to store sperm relieves individuals of a dependence on the synchronisation of spawning of eggs and sperm. As the population size and density increases, there could be more individuals releasing sperm into the water column, resulting in a continuous supply of sperm. The increased production of eggs would therefore not be constrained by a lack of sperm. The stored sperm are released into the brood chamber to fertilise eggs as they are laid, and this would probably increase the fertilisation success in the species. This study also provides evidence to suggest that reproduction in this worm has a seasonal component. Future studies should concentrate on measuring fertilisation success in greater detail, measuring the effect of season on reproduction, determining whether there are genetic differences between worms on farmed and wild abalone and determining whether wild worms have similar life-spans and age-related fecundity as worms on farms.
- Full Text:
The motivating force of moral beliefs
- Authors: Vos, James Antony
- Date: 2005 , 2013-06-14
- Subjects: Hume, David, 1711-1776 -- Ethics , Ethics , Motivation , Practical reason , Rationalism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2729 , http://hdl.handle.net/10962/d1003804 , Hume, David, 1711-1776 -- Ethics , Ethics , Motivation , Practical reason , Rationalism
- Description: I investigate the issue of whether or not one's holding a moral belief is sufficient to motivate one to act as that belief prescribes. I argue that rational persons who hold a moral belief that is also a 'self-referential belief' will form a desire to act as that belief prescribes and thereby be motivated to act on the moral belief. I argue for this claim by, firstly, showing that the demand that moral judgements must be intrinsically motivating, Internalism, should only apply to rational persons, that is, the link between moral judgement and motivation can be broken in cases of irrationality. Secondly, I argue against the Humean claim that one cannot rationally form a desire simply because one believes that one ought to have that desire. This claim requires an investigation into a variety of views of Practical Reason and an argument concluding that Practical Reason is broader in scope than the Instrumentalist or Humean allows. I undertake this task in chapter 2. Thirdly, I argue that believing that I ought to perform a certain action will give me an internal commitment to perform that action, insofar as I am rational. I argue that an internal commitment is a form of desire. Once I recognise that I have a moral belief and an internal commitment, I will be motivated to act as that belief and commitment prescribe. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Vos, James Antony
- Date: 2005 , 2013-06-14
- Subjects: Hume, David, 1711-1776 -- Ethics , Ethics , Motivation , Practical reason , Rationalism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2729 , http://hdl.handle.net/10962/d1003804 , Hume, David, 1711-1776 -- Ethics , Ethics , Motivation , Practical reason , Rationalism
- Description: I investigate the issue of whether or not one's holding a moral belief is sufficient to motivate one to act as that belief prescribes. I argue that rational persons who hold a moral belief that is also a 'self-referential belief' will form a desire to act as that belief prescribes and thereby be motivated to act on the moral belief. I argue for this claim by, firstly, showing that the demand that moral judgements must be intrinsically motivating, Internalism, should only apply to rational persons, that is, the link between moral judgement and motivation can be broken in cases of irrationality. Secondly, I argue against the Humean claim that one cannot rationally form a desire simply because one believes that one ought to have that desire. This claim requires an investigation into a variety of views of Practical Reason and an argument concluding that Practical Reason is broader in scope than the Instrumentalist or Humean allows. I undertake this task in chapter 2. Thirdly, I argue that believing that I ought to perform a certain action will give me an internal commitment to perform that action, insofar as I am rational. I argue that an internal commitment is a form of desire. Once I recognise that I have a moral belief and an internal commitment, I will be motivated to act as that belief and commitment prescribe. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
The nature and potential of industrial development within the Southern African Development Community (SADC) and the facilitating role of trade liberalisation and foreign direct investment in selected countries
- Authors: Mutambara, Tsitsi Effie
- Date: 2005
- Subjects: Southern African Development Community Investments, Foreign -- Africa, Southern Free trade -- Africa, Southern Economic development -- Africa, Southern Industrialization -- Africa, Southern Industrial policy -- Africa, Southern Africa, Southern -- Economic policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1071 , http://hdl.handle.net/10962/d1007732
- Description: To date the SADC region has managed to develop a manufacturing base but this base is still small as evidenced by its low contribution to GDP. For example, only three out of the fourteen SADC countries, viz. Mauritius, South Africa and Swaziland, had over 20 percent of their GDP originating from the manufacturing sector throughout the 1990s. Also to note is that while the manufacturing sector is quite diversified, the sector is dominated by industrial processes which are more of resource and labour-intensive in nature than those processes of scale-intensive, differentiated and science based in nature. TIle trade performance of the manufacturing sector supports these observations and as such the region is heavily dependent on imports for scale-intensive, differentiated and science based commodities. However, despite the fact that the region tends to focus more on resource- and labour-intensive manufacturing activities, products from these manufacturing activities are still significant components of manufactured goods imports into the region. Also to note is that since resource- and labour-intensive industries dominate manufacturing activities; these are the areas in which investment opportunities abound. For example, agro-based manufacturing presents most of the investment opportunities, with food processing presenting the majority of the investment opportunities followed by garments and textiles production. Mineral processing also presents significant investment opportunities. The analyses of the nature of the manufacturing sector also show that in a few SADC countries, viz. Mauritius, South Africa and Zimbabwe; scale-intensive, differentiated and science based industries also form a significant component of the industrial base implying more technologically complex manufacturing sectors. Since high technology and technologically complex manufacturing activities are limited, investment opportunities in these manufacturing sub-sectors are also limited to just a few countries However, with the SADC ITA in place, opportunities could arise for these limited technology-related manufacturing facilities to expand or engage in import substitution production so as to meet the demands of the growing regional market. It is also important to note that, while the region may not have as competitive advantage in these industries as in the resource- and labour-intensive industries, there is a need for the region to selectively identify and target such industries for priority development, a lesson SADC could learn from the East Asian NIC's took in their industrialisation strategy. The study also shows that the manufacturing sector has been a priority sector for both domestic and foreign investors. This has implications for industrial development because a strong and dynamic manufacturing sector would be developed, forming a sound basis for industrialisation as well as being able to effectively link and support all the other sectors of the economy. FDI could help the region to fully utilise the labour-intensive industries and use them as a stepping-stone to higher levels of industrial development. This is a lesson to SADC from the experiences of the East Asian NICs where while industrialisation was initiated by labour-intensive manufacturing, the countries were able to move into capital-intensive manufacturing due to FDI as it enabled the establishment of the industrial bases, thus leading to a rise in the share of manufactured exports. FDI could also help to develop the resource-intensive industries further by promoting further processing of raw materials into products of more value, thus propelling industrialisation through a resource-led industrial development programme as the current resource-intensive industries become fully utilised. The raw materials which occur in great abundance in the region's primary sector would have a ready market in the manufacturing sector where they would serve as inputs to the production of high value products. The currently smaller industrial base for scale-intensive products, differentiated and science-based manufactured products would benefit from the improved technological capabilities and managerial skills that result from FDI. Therefore, by impacting positively on manufacturing activities of both low and high MVA, FDI would thus have a facilitating role in establishing a more solid industrial base, broadening the current manufacturing base, and improving installed capacity utilisation. The study also shows that investment in productive capacity in the form of machinery and equipment is of great importance in the sampled SADC countries. Investment towards the acquisition of this capital is very important as this is directly relevant towards improving productive capacity. FDI could thus play a facilitating role by augmenting the current domestic investment in machinery and equipment. While the manufacturing sector within the region is still small and the current utilisation of installed industrial capacity is low, there is potential for further industrial growth. The current process to usher in the SADC Free Trade Area would have a facilitating role through various ways: viz. increasing the market size and enabling easier access through the reduction of tariff and non-tariff barriers, promoting regional competitiveness, improved utilisation of regional corridors, increasing opportunities for utilising identified intra-industry trade potentials, and providing opportunities for increased regional cross-border investment. Apart from the SADC FTA, the USA African Growth and Opportunity Act (AGOA) and the Cotonou Agreement will also motivate the identification and utilisation of existing and new potentials within the manufacturing sector in SADC. In order to improve the current nature of industries in the region, there is also a need to design and implement appropriate industrial policies and strategies. Such policies should consider the region's trade policies and the recently launched Regional Indicative Strategic Development Plan (RISDP) so as to complement them. The industrial policies should also address issues relating to industrial investment, technology and local technological capabilities development, human resources development, the structure and nature of industry, the competitiveness of industries, as well as facilitating the complementarities between the agricultural and manufacturing sectors. To this end therefore, instead of relying solely on individual national industrial policies, SADC is in the process of formulating a regional industrial policy and strategies which seek to promote and support sustainable industrial growth across the region, thus facilitating industrial development.
- Full Text:
- Authors: Mutambara, Tsitsi Effie
- Date: 2005
- Subjects: Southern African Development Community Investments, Foreign -- Africa, Southern Free trade -- Africa, Southern Economic development -- Africa, Southern Industrialization -- Africa, Southern Industrial policy -- Africa, Southern Africa, Southern -- Economic policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1071 , http://hdl.handle.net/10962/d1007732
- Description: To date the SADC region has managed to develop a manufacturing base but this base is still small as evidenced by its low contribution to GDP. For example, only three out of the fourteen SADC countries, viz. Mauritius, South Africa and Swaziland, had over 20 percent of their GDP originating from the manufacturing sector throughout the 1990s. Also to note is that while the manufacturing sector is quite diversified, the sector is dominated by industrial processes which are more of resource and labour-intensive in nature than those processes of scale-intensive, differentiated and science based in nature. TIle trade performance of the manufacturing sector supports these observations and as such the region is heavily dependent on imports for scale-intensive, differentiated and science based commodities. However, despite the fact that the region tends to focus more on resource- and labour-intensive manufacturing activities, products from these manufacturing activities are still significant components of manufactured goods imports into the region. Also to note is that since resource- and labour-intensive industries dominate manufacturing activities; these are the areas in which investment opportunities abound. For example, agro-based manufacturing presents most of the investment opportunities, with food processing presenting the majority of the investment opportunities followed by garments and textiles production. Mineral processing also presents significant investment opportunities. The analyses of the nature of the manufacturing sector also show that in a few SADC countries, viz. Mauritius, South Africa and Zimbabwe; scale-intensive, differentiated and science based industries also form a significant component of the industrial base implying more technologically complex manufacturing sectors. Since high technology and technologically complex manufacturing activities are limited, investment opportunities in these manufacturing sub-sectors are also limited to just a few countries However, with the SADC ITA in place, opportunities could arise for these limited technology-related manufacturing facilities to expand or engage in import substitution production so as to meet the demands of the growing regional market. It is also important to note that, while the region may not have as competitive advantage in these industries as in the resource- and labour-intensive industries, there is a need for the region to selectively identify and target such industries for priority development, a lesson SADC could learn from the East Asian NIC's took in their industrialisation strategy. The study also shows that the manufacturing sector has been a priority sector for both domestic and foreign investors. This has implications for industrial development because a strong and dynamic manufacturing sector would be developed, forming a sound basis for industrialisation as well as being able to effectively link and support all the other sectors of the economy. FDI could help the region to fully utilise the labour-intensive industries and use them as a stepping-stone to higher levels of industrial development. This is a lesson to SADC from the experiences of the East Asian NICs where while industrialisation was initiated by labour-intensive manufacturing, the countries were able to move into capital-intensive manufacturing due to FDI as it enabled the establishment of the industrial bases, thus leading to a rise in the share of manufactured exports. FDI could also help to develop the resource-intensive industries further by promoting further processing of raw materials into products of more value, thus propelling industrialisation through a resource-led industrial development programme as the current resource-intensive industries become fully utilised. The raw materials which occur in great abundance in the region's primary sector would have a ready market in the manufacturing sector where they would serve as inputs to the production of high value products. The currently smaller industrial base for scale-intensive products, differentiated and science-based manufactured products would benefit from the improved technological capabilities and managerial skills that result from FDI. Therefore, by impacting positively on manufacturing activities of both low and high MVA, FDI would thus have a facilitating role in establishing a more solid industrial base, broadening the current manufacturing base, and improving installed capacity utilisation. The study also shows that investment in productive capacity in the form of machinery and equipment is of great importance in the sampled SADC countries. Investment towards the acquisition of this capital is very important as this is directly relevant towards improving productive capacity. FDI could thus play a facilitating role by augmenting the current domestic investment in machinery and equipment. While the manufacturing sector within the region is still small and the current utilisation of installed industrial capacity is low, there is potential for further industrial growth. The current process to usher in the SADC Free Trade Area would have a facilitating role through various ways: viz. increasing the market size and enabling easier access through the reduction of tariff and non-tariff barriers, promoting regional competitiveness, improved utilisation of regional corridors, increasing opportunities for utilising identified intra-industry trade potentials, and providing opportunities for increased regional cross-border investment. Apart from the SADC FTA, the USA African Growth and Opportunity Act (AGOA) and the Cotonou Agreement will also motivate the identification and utilisation of existing and new potentials within the manufacturing sector in SADC. In order to improve the current nature of industries in the region, there is also a need to design and implement appropriate industrial policies and strategies. Such policies should consider the region's trade policies and the recently launched Regional Indicative Strategic Development Plan (RISDP) so as to complement them. The industrial policies should also address issues relating to industrial investment, technology and local technological capabilities development, human resources development, the structure and nature of industry, the competitiveness of industries, as well as facilitating the complementarities between the agricultural and manufacturing sectors. To this end therefore, instead of relying solely on individual national industrial policies, SADC is in the process of formulating a regional industrial policy and strategies which seek to promote and support sustainable industrial growth across the region, thus facilitating industrial development.
- Full Text:
The perceived impact of policy change on leadership and management : a case study of a Namibian school
- Moelanjane, Porgarius Porgacy Rukee
- Authors: Moelanjane, Porgarius Porgacy Rukee
- Date: 2005
- Subjects: School management and organization -- Namibia -- Case studies. Educational leadership -- Namibia -- Case studies Educational change -- Namibia -- Case studies Education and state -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1935 , http://hdl.handle.net/10962/d1007670
- Description: The transformation of education has been central to the programme of the first democratically elected government in Namibia, both because of the democratic demands for equality, equity and access, and as a means towards the wider transformation of Namibian community. The study provides a brief history of the pre- and post-independence education policy environment in Namibia with regard to how management and leadership of schools gave rise to opportunities for the development of democratic participation. Adopting an interpretive approach, the study examines several key stakeholders' perceptions of the impact of transformation initiatives on their leadership and management thinking and practice. The sample comprised four teachers, a principal, a director, a school board member, two learners and a hostel matron. The findings reveal that, in order to create a democratic school community, the stakeholders' role is largely a matter of opposing and transcending the contradictions, inadequacies and limitations inherent in the educational ideas, policies and practices caused by the previous Apartheid education system. There is a reasonable amount of success in the implementation process of democratic leadership and management of schools. The findings further highlight contradictory tendencies, in that the Ministry of Basic Education Sports and Culture established a uniform system of education but also entertained the principle of decentralised governance through the introduction of school based management practice incorporating the main stakeholders at local level. The data confirms a communication gap between stakeholders, lack of adequate education and training in participatory management and leadership for learners, parents, teachers and school boards, and insufficient support from the national and the regional authorities. The study concludes with some specific recommendations that might strengthen stakeholders' sense of their participation in democratic practices for longer-term cost effective implementation to occur. This is supported by the belief that education policy change only becomes a reality once understood, owned and appreciated at local level.
- Full Text:
- Authors: Moelanjane, Porgarius Porgacy Rukee
- Date: 2005
- Subjects: School management and organization -- Namibia -- Case studies. Educational leadership -- Namibia -- Case studies Educational change -- Namibia -- Case studies Education and state -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1935 , http://hdl.handle.net/10962/d1007670
- Description: The transformation of education has been central to the programme of the first democratically elected government in Namibia, both because of the democratic demands for equality, equity and access, and as a means towards the wider transformation of Namibian community. The study provides a brief history of the pre- and post-independence education policy environment in Namibia with regard to how management and leadership of schools gave rise to opportunities for the development of democratic participation. Adopting an interpretive approach, the study examines several key stakeholders' perceptions of the impact of transformation initiatives on their leadership and management thinking and practice. The sample comprised four teachers, a principal, a director, a school board member, two learners and a hostel matron. The findings reveal that, in order to create a democratic school community, the stakeholders' role is largely a matter of opposing and transcending the contradictions, inadequacies and limitations inherent in the educational ideas, policies and practices caused by the previous Apartheid education system. There is a reasonable amount of success in the implementation process of democratic leadership and management of schools. The findings further highlight contradictory tendencies, in that the Ministry of Basic Education Sports and Culture established a uniform system of education but also entertained the principle of decentralised governance through the introduction of school based management practice incorporating the main stakeholders at local level. The data confirms a communication gap between stakeholders, lack of adequate education and training in participatory management and leadership for learners, parents, teachers and school boards, and insufficient support from the national and the regional authorities. The study concludes with some specific recommendations that might strengthen stakeholders' sense of their participation in democratic practices for longer-term cost effective implementation to occur. This is supported by the belief that education policy change only becomes a reality once understood, owned and appreciated at local level.
- Full Text:
The politics of humanitarian organizations neutrality and solidarity: the case of the ICRC and MSF during the 1994 Rwandan genocide
- Authors: Delvaux, Denise
- Date: 2005
- Subjects: International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2769 , http://hdl.handle.net/10962/d1002979 , International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Description: With the seemingly infinite existence of complex emergencies and the overwhelming presence of humanitarian organizations responding to such crises, it is essential that the assumptions, precepts, and actions of humanitarian organizations be critically examined and understood. The aim of this thesis is to explore differing traditions within humanitarian thought: neutrality and solidarity. In the process, this thesis will determine whether it is possible to maintain clear ideologies in the context of a complex emergency and whether the existence of different humanitarian ideologies results in a dichotomy or polarization of humanitarian action. This study is of great import as it delves into the contemporary literature claiming that humanitarianism is currently in a state of crisis – the unsustainability of competing humanitarian ideologies operating together in a complex emergency. Primary documents from both the International Committee of the Red Cross (ICRC) and Médecins Sans Frontières (MSF) regarding their operations in the 1994 Rwandan complex emergency were examined in order to provide a foundation for the theoretical investigation. Although the ICRC and MSF occupy seemingly polarized positions in the neutrality – solidarity debate, the investigation into their humanitarian activities during the 1994 genocide and the resulting refugee crisis reflected the difficulties of providing relief based upon humanitarian ideals. Due to the complex realities of the 1994 Rwandan crisis, the ideological notions dividing the ICRC and MSF were overshadowed by the simple humanitarian desire to aid those in need.
- Full Text:
- Authors: Delvaux, Denise
- Date: 2005
- Subjects: International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2769 , http://hdl.handle.net/10962/d1002979 , International Committee of the Red Cross -- History , Médecins sans frontières (Association) , Humanitarian intervention , Neutrality -- Rwanda , Solidarity -- Rwanda , Genocide -- Rwanda -- History -- 20th century , Genocide -- Rwanda , Rwanda -- History -- Civil War, 1994 , Rwanda -- Politics and government
- Description: With the seemingly infinite existence of complex emergencies and the overwhelming presence of humanitarian organizations responding to such crises, it is essential that the assumptions, precepts, and actions of humanitarian organizations be critically examined and understood. The aim of this thesis is to explore differing traditions within humanitarian thought: neutrality and solidarity. In the process, this thesis will determine whether it is possible to maintain clear ideologies in the context of a complex emergency and whether the existence of different humanitarian ideologies results in a dichotomy or polarization of humanitarian action. This study is of great import as it delves into the contemporary literature claiming that humanitarianism is currently in a state of crisis – the unsustainability of competing humanitarian ideologies operating together in a complex emergency. Primary documents from both the International Committee of the Red Cross (ICRC) and Médecins Sans Frontières (MSF) regarding their operations in the 1994 Rwandan complex emergency were examined in order to provide a foundation for the theoretical investigation. Although the ICRC and MSF occupy seemingly polarized positions in the neutrality – solidarity debate, the investigation into their humanitarian activities during the 1994 genocide and the resulting refugee crisis reflected the difficulties of providing relief based upon humanitarian ideals. Due to the complex realities of the 1994 Rwandan crisis, the ideological notions dividing the ICRC and MSF were overshadowed by the simple humanitarian desire to aid those in need.
- Full Text:
The potential of claywork to facilitate the integration of the self in psychotherapy with an adult survivor of childhood trauma: a Jungian perspective
- Authors: Smuts, Tanja
- Date: 2005
- Subjects: Jung, C G (Carl Gustav), 1875-1961 , Art therapy , Psychotherapy , Child psychotherapy , Adult child abuse victims -- Rehabilitation , Self , Modeling -- Therapeutic use
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3062 , http://hdl.handle.net/10962/d1002571 , Jung, C G (Carl Gustav), 1875-1961 , Art therapy , Psychotherapy , Child psychotherapy , Adult child abuse victims -- Rehabilitation , Self , Modeling -- Therapeutic use
- Description: The aim of this thesis was to explore the experience of “self” within the clinical context of adult survivors of childhood trauma. Childhood trauma in this study referred to a range of childhood experiences of emotional and physical assault, including encounters with various kinds of abuse and neglect. The focus was on the experience of a sense of disintegration and dislocation, associated to aspects of self being in conflict. This was explored from theoretical perspectives of Jungian analytic psychology, as well as art therapy.Answers were sought to the questions of how claywork, as a form of art therapy, may facilitate the integration of the self and contribute to the development of a healing dialogue with feared and hated aspects of self. Grounded in Jungian theory, integration of the self was conceptualised as a movement towards “differentiating wholeness”. The study took the form of a phenomenological-hermeneutic case study. One participant’s experience of making and discussing a clay sculpture in a therapeutic setting according to Edwards’ method, was analysed thematically. It was concluded that the potential of claywork in therapy to facilitate the integration of the self is related to three aspects. Firstly, claywork in therapy may promote a concrete personification of feared and hated aspects of self, which may enable the maker to view these aspects from a distance, and learn to understand them in a new way. Secondly, claywork in therapy may facilitate the safe ‘unearthing’ of repressed feelings as well as hidden aspects of the personality. Thirdly, claywork’s potential to mediate symbolic functioning was shown to be an important aspect of the integration process. These findings confirmed and extended existing theory regarding the usefulness of claywork in psychotherapy with adult survivors of childhood trauma. Brief recommendations for future research were provided.
- Full Text:
- Authors: Smuts, Tanja
- Date: 2005
- Subjects: Jung, C G (Carl Gustav), 1875-1961 , Art therapy , Psychotherapy , Child psychotherapy , Adult child abuse victims -- Rehabilitation , Self , Modeling -- Therapeutic use
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3062 , http://hdl.handle.net/10962/d1002571 , Jung, C G (Carl Gustav), 1875-1961 , Art therapy , Psychotherapy , Child psychotherapy , Adult child abuse victims -- Rehabilitation , Self , Modeling -- Therapeutic use
- Description: The aim of this thesis was to explore the experience of “self” within the clinical context of adult survivors of childhood trauma. Childhood trauma in this study referred to a range of childhood experiences of emotional and physical assault, including encounters with various kinds of abuse and neglect. The focus was on the experience of a sense of disintegration and dislocation, associated to aspects of self being in conflict. This was explored from theoretical perspectives of Jungian analytic psychology, as well as art therapy.Answers were sought to the questions of how claywork, as a form of art therapy, may facilitate the integration of the self and contribute to the development of a healing dialogue with feared and hated aspects of self. Grounded in Jungian theory, integration of the self was conceptualised as a movement towards “differentiating wholeness”. The study took the form of a phenomenological-hermeneutic case study. One participant’s experience of making and discussing a clay sculpture in a therapeutic setting according to Edwards’ method, was analysed thematically. It was concluded that the potential of claywork in therapy to facilitate the integration of the self is related to three aspects. Firstly, claywork in therapy may promote a concrete personification of feared and hated aspects of self, which may enable the maker to view these aspects from a distance, and learn to understand them in a new way. Secondly, claywork in therapy may facilitate the safe ‘unearthing’ of repressed feelings as well as hidden aspects of the personality. Thirdly, claywork’s potential to mediate symbolic functioning was shown to be an important aspect of the integration process. These findings confirmed and extended existing theory regarding the usefulness of claywork in psychotherapy with adult survivors of childhood trauma. Brief recommendations for future research were provided.
- Full Text:
The refinement of protective salinity guidelines for South African freshwater resources
- Authors: Slaughter, Andrew Robert
- Date: 2005
- Subjects: Water salinization -- South Africa Salinization -- Control -- South Africa Salinity -- South Africa Freshwater ecology -- South Africa Water resources development -- South Africa Caridina Caridina -- Effect of pollution
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6031 , http://hdl.handle.net/10962/d1006170
- Description: South Africa is an arid country and its growing population is putting freshwater resources under increasing pressure. Natural salinization of freshwater systems is being exacerbated by anthropogenic influences. The National Water Act (No. 36 of 1998) stipulates the need for an ecological Reserve, that quantity and quality of freshwater needed to protect freshwater ecosystems while allowing sustainable use of freshwater resources. Water guidelines do exist in the form of the South African Water Quality Guidelines (DWAF, 1996) and more recently, Jooste and Rossouw (2002) compiled benchmark values for water quality variables marking the boundaries between ecological health classes in the 4-category classification system. Predominantly international toxicity data were used to compile the guidelines and the benchmark values. In addition, there is a paucity of chronic toxicity data nationally and internationally. This thesis showed that it is statistically possible to derive protective chronic endpoints for salinity from acute toxicity data through extrapolation. The Acute to Chronic Ratio (ACR), Two-Step Linear Regression (LRA) and Multi-Factor Probit Analysis (MPA) extrapolation methods were investigated to derive chronic toxicity data from acute toxicity data. The authors of LRA and MPA recommend associating a time independent LCx value in the range of LC₀¸₀₁ to LC₁₀ with a Predicted No Effect Concentration (PNOEC). In addition to published methods, this thesis studied the possibility of equating a time independent LC₅₀ value and subjected to a safety factor of 5 (LRA LC₅₀/5), to the PNOEC. Extrapolated chronic toxicity data where the toxicants are NaCl and Na₂SO₄ were derived for indigenous South African macroinvertebrates. NaCl and Na₂SO₄ are salts associated with salinisation in South Africa. In addition, a chronic salinity toxicity test protocol for an indigenous South African aquatic macroinvertebrate was designed and chronic toxicity test were performed using NaCl and Na₂SO₄ as toxicants. The experimental chronic toxicity data produced were used to validate results from the acute to chronic extrapolation methods. Extrapolated chronic toxicity data were inputted into Species Sensitivity Distribution curves, and concentrations that were predicted to protect 95 % of species (PC95) were compared to the sub-lethality benchmarks proposed by Jooste and Rossouw (2002) for NaCl and Na₂SO₄. This study concluded that the LRA LC₅₀/5 extrapolation method is the most protective and accurate and proposed that LRA replace the ACR method in future guideline development for inorganic salts.
- Full Text:
- Authors: Slaughter, Andrew Robert
- Date: 2005
- Subjects: Water salinization -- South Africa Salinization -- Control -- South Africa Salinity -- South Africa Freshwater ecology -- South Africa Water resources development -- South Africa Caridina Caridina -- Effect of pollution
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6031 , http://hdl.handle.net/10962/d1006170
- Description: South Africa is an arid country and its growing population is putting freshwater resources under increasing pressure. Natural salinization of freshwater systems is being exacerbated by anthropogenic influences. The National Water Act (No. 36 of 1998) stipulates the need for an ecological Reserve, that quantity and quality of freshwater needed to protect freshwater ecosystems while allowing sustainable use of freshwater resources. Water guidelines do exist in the form of the South African Water Quality Guidelines (DWAF, 1996) and more recently, Jooste and Rossouw (2002) compiled benchmark values for water quality variables marking the boundaries between ecological health classes in the 4-category classification system. Predominantly international toxicity data were used to compile the guidelines and the benchmark values. In addition, there is a paucity of chronic toxicity data nationally and internationally. This thesis showed that it is statistically possible to derive protective chronic endpoints for salinity from acute toxicity data through extrapolation. The Acute to Chronic Ratio (ACR), Two-Step Linear Regression (LRA) and Multi-Factor Probit Analysis (MPA) extrapolation methods were investigated to derive chronic toxicity data from acute toxicity data. The authors of LRA and MPA recommend associating a time independent LCx value in the range of LC₀¸₀₁ to LC₁₀ with a Predicted No Effect Concentration (PNOEC). In addition to published methods, this thesis studied the possibility of equating a time independent LC₅₀ value and subjected to a safety factor of 5 (LRA LC₅₀/5), to the PNOEC. Extrapolated chronic toxicity data where the toxicants are NaCl and Na₂SO₄ were derived for indigenous South African macroinvertebrates. NaCl and Na₂SO₄ are salts associated with salinisation in South Africa. In addition, a chronic salinity toxicity test protocol for an indigenous South African aquatic macroinvertebrate was designed and chronic toxicity test were performed using NaCl and Na₂SO₄ as toxicants. The experimental chronic toxicity data produced were used to validate results from the acute to chronic extrapolation methods. Extrapolated chronic toxicity data were inputted into Species Sensitivity Distribution curves, and concentrations that were predicted to protect 95 % of species (PC95) were compared to the sub-lethality benchmarks proposed by Jooste and Rossouw (2002) for NaCl and Na₂SO₄. This study concluded that the LRA LC₅₀/5 extrapolation method is the most protective and accurate and proposed that LRA replace the ACR method in future guideline development for inorganic salts.
- Full Text:
The relationship between leadership and internal customer satisfaction within a motor manufacturing company in Gauteng
- Authors: Samuel, Glen
- Date: 2005
- Subjects: Automobile industry and trade -- Employees -- South Africa -- Gauteng Automobile industry and trade -- Customer services -- South Africa -- Gauteng Job satisfaction Customer services -- Management Industrial relations -- South Africa -- Gauteng Employee morale Personnel management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:758 , http://hdl.handle.net/10962/d1003879
- Description: This research investigates the relationship between leadership and internal customer satisfaction, also called employee satisfaction in this document. The research is conducted within an automotive manufacturer situated in the province of Gauteng, South Africa. The Service Profit Chain forms the foundation on which this research is based as it suggests that the various factors within the service delivery system of an organisation ultimately affect the success of an organisation. From the Service Profit Chain, it is established that a factor that affects employee satisfaction is the leadership within the organisation. The Full Range Leadership Development Theory provides the backbone for analysing the leadership style of each manager by using the Multifactor Leadership Questionnaire. The company’s employee satisfaction model provides the theoretical construct against which the employee satisfaction of the managers’ subordinates is measured using the company’s employee satisfaction questionnaire. Information was gathered from the managers who rated their leadership styles as they perceived it; and from their respective subordinates who rated the managers’ leadership style as they perceived it and also their satisfaction as employees as they perceived it. Data obtained from each instrument, for the respective managers, was then statistically analysed. The reliability of the data could not be proved for some of the factors of the 2 research instruments. However, this research found a statistically significant relationship between transformational leadership and some factors of employee satisfaction, albeit a weak relationship. The null hypothesis was rejected and the alternate hypothesis accepted. A statistically significant relationship exists between leadership style and employee satisfaction levels within an automotive manufacturing organisation.
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- Authors: Samuel, Glen
- Date: 2005
- Subjects: Automobile industry and trade -- Employees -- South Africa -- Gauteng Automobile industry and trade -- Customer services -- South Africa -- Gauteng Job satisfaction Customer services -- Management Industrial relations -- South Africa -- Gauteng Employee morale Personnel management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:758 , http://hdl.handle.net/10962/d1003879
- Description: This research investigates the relationship between leadership and internal customer satisfaction, also called employee satisfaction in this document. The research is conducted within an automotive manufacturer situated in the province of Gauteng, South Africa. The Service Profit Chain forms the foundation on which this research is based as it suggests that the various factors within the service delivery system of an organisation ultimately affect the success of an organisation. From the Service Profit Chain, it is established that a factor that affects employee satisfaction is the leadership within the organisation. The Full Range Leadership Development Theory provides the backbone for analysing the leadership style of each manager by using the Multifactor Leadership Questionnaire. The company’s employee satisfaction model provides the theoretical construct against which the employee satisfaction of the managers’ subordinates is measured using the company’s employee satisfaction questionnaire. Information was gathered from the managers who rated their leadership styles as they perceived it; and from their respective subordinates who rated the managers’ leadership style as they perceived it and also their satisfaction as employees as they perceived it. Data obtained from each instrument, for the respective managers, was then statistically analysed. The reliability of the data could not be proved for some of the factors of the 2 research instruments. However, this research found a statistically significant relationship between transformational leadership and some factors of employee satisfaction, albeit a weak relationship. The null hypothesis was rejected and the alternate hypothesis accepted. A statistically significant relationship exists between leadership style and employee satisfaction levels within an automotive manufacturing organisation.
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The role of a principal in an academically successful farm school: a case study
- Nongauza, Anthony Davidson Mbulelo
- Authors: Nongauza, Anthony Davidson Mbulelo
- Date: 2005
- Subjects: School principals -- South Africa -- Case studies School management and organization -- South Africa -- Case studies Rural schools -- South Africa -- Case studies Education, Rural -- South Africa -- Case studies School supervision, Rural -- South Africa -- Case studies Rural schools -- South Africa -- Administration of -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1747 , http://hdl.handle.net/10962/d1003631
- Description: This study looks at the various actions by the principal of a farm school in running an academically successful school. The study exposes the difficulties faced by farm schools and looks at how the principal confronts these difficulties and turn some of these into success stories. In trying to understand the role of the principal this study uses school effectiveness literature as a source and reference in an attempt to understand the actions adopted by the principal to make this farm school successful. The study uses the interpretive orientation as the methodology for investigating the principal’s role. This is in line with my attempt at explaining the perceptions, views and experiences of the people who are working closely with the principal. I have done this by employing semi-structured interviews and participant observation. The information gathered from the respondents helped in the development of the role of the principal which in this case, is the expressed views of the respondents. The investigation is conducted as a case study and the handling of the information provided by the respondents is in line with case study methods. The study has revealed that actions of the leader have an influence on the organizational success. The way in which the leader of Rocklands farm School conducts herself and the vision she shares with the people within the organization go a long way towards the improvement of organizational structures and their functioning. In this case the principal has been noted as particularly transformational, charismatic, instructional and transactional in her approaches to school administration and that her dedication to the cause of learners from disadvantaged background is reflected in her sacrificial actions. The study has also found that the principal is considered to be fairly autocratic in her leadership, which is a departure from current leadership thinking. The study has also shown that socio-economic disadvantages do not necessarily inhibit the school from performing beyond expectation. With good guidance from the leader and trust among staff members the farm school has been able to overcome some socio-economic pressures to emerge successful in the academic field. The fact that the principal of this school is a woman has not changed the overall findings that leadership qualities for successful schooling are universal and do not necessarily depend on the gender of the leader. This study suggests that leaders have a potential to turn poor situations in schools around and that leaders should as a matter of course ensure that they understand the organizational dynamics within their schools. They should be in the forefront as agents of change being mindful that those within the school understand and share the vision the leader has. The study also suggests that the human element in the educational processes in schools is of critical importance than the conditions in which schools find themselves.
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- Authors: Nongauza, Anthony Davidson Mbulelo
- Date: 2005
- Subjects: School principals -- South Africa -- Case studies School management and organization -- South Africa -- Case studies Rural schools -- South Africa -- Case studies Education, Rural -- South Africa -- Case studies School supervision, Rural -- South Africa -- Case studies Rural schools -- South Africa -- Administration of -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1747 , http://hdl.handle.net/10962/d1003631
- Description: This study looks at the various actions by the principal of a farm school in running an academically successful school. The study exposes the difficulties faced by farm schools and looks at how the principal confronts these difficulties and turn some of these into success stories. In trying to understand the role of the principal this study uses school effectiveness literature as a source and reference in an attempt to understand the actions adopted by the principal to make this farm school successful. The study uses the interpretive orientation as the methodology for investigating the principal’s role. This is in line with my attempt at explaining the perceptions, views and experiences of the people who are working closely with the principal. I have done this by employing semi-structured interviews and participant observation. The information gathered from the respondents helped in the development of the role of the principal which in this case, is the expressed views of the respondents. The investigation is conducted as a case study and the handling of the information provided by the respondents is in line with case study methods. The study has revealed that actions of the leader have an influence on the organizational success. The way in which the leader of Rocklands farm School conducts herself and the vision she shares with the people within the organization go a long way towards the improvement of organizational structures and their functioning. In this case the principal has been noted as particularly transformational, charismatic, instructional and transactional in her approaches to school administration and that her dedication to the cause of learners from disadvantaged background is reflected in her sacrificial actions. The study has also found that the principal is considered to be fairly autocratic in her leadership, which is a departure from current leadership thinking. The study has also shown that socio-economic disadvantages do not necessarily inhibit the school from performing beyond expectation. With good guidance from the leader and trust among staff members the farm school has been able to overcome some socio-economic pressures to emerge successful in the academic field. The fact that the principal of this school is a woman has not changed the overall findings that leadership qualities for successful schooling are universal and do not necessarily depend on the gender of the leader. This study suggests that leaders have a potential to turn poor situations in schools around and that leaders should as a matter of course ensure that they understand the organizational dynamics within their schools. They should be in the forefront as agents of change being mindful that those within the school understand and share the vision the leader has. The study also suggests that the human element in the educational processes in schools is of critical importance than the conditions in which schools find themselves.
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The role of acute toxicity data for South African freshwater macroinvertebrates in the derivation of water quality guidelines for salinity
- Authors: Browne, Samantha
- Date: 2005
- Subjects: Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4742 , http://hdl.handle.net/10962/d1006173 , Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Description: Water resources are under ever-increasing pressure to meet the demands of various water users both nationally and internationally. The process of anthropogenically-induced salinisation serves to exacerbate this pressure by limiting the quantity and quality of water available for future use. Water quality guidelines provide the numerical goals which water resource managers can use to adequately manage and protect aquatic ecosystems. Various methods which have been developed and used internationally to derive such guidelines are discussed. Acute toxicity tests were conducted using two inorganic salts, NaCl and Na₂SO₄. Field collected, indigenous, freshwater macroinvertebrates were used as tests organisms. Data generated from these tests contributed to the expansion of the currently limited toxicological database of response data for indigenous organisms and the suitability of using such organisms for future testing was discussed. Salt sensitivities of indigenous freshwater invertebrates were compared those of species sourced from an international toxicological database and were found to have similar ranges of tolerances to NaCl and Na₂SO₄. Species sensitivity distributions (SSDs), a method of data extrapolation, were derived using different types of toxicological data, and hence different guideline values or protective concentrations were derived. These concentrations were equated to boundary values for South Africa’s ecological Reserve categories, which are used to describe degrees of health for aquatic ecosystems. Provisional results suggest that using only acute toxicity data in guideline derivation provides ecosystem protection that is under-protective. Chronic toxicity data, which include endpoints other than mortality, provide the most realistic environmental protection but lack data confidence due to small sample sizes (acute tests are more readily conducted than chronic tests). The potential contribution of sub-chronic data to guideline derivation is highlighted as these data are more readily extrapolated to chronic endpoints than acute data and sub-chronic tests are not as complex and demanding to conduct as chronic tests.
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- Authors: Browne, Samantha
- Date: 2005
- Subjects: Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4742 , http://hdl.handle.net/10962/d1006173 , Water-supply -- South Africa , Water quality management -- South Africa , Aquatic ecology -- South Africa , Ecosystem management -- South Africa , Freshwater invertebrates -- South Africa -- Ecology , Water -- Toxicology -- South Africa , Water quality biological assessment
- Description: Water resources are under ever-increasing pressure to meet the demands of various water users both nationally and internationally. The process of anthropogenically-induced salinisation serves to exacerbate this pressure by limiting the quantity and quality of water available for future use. Water quality guidelines provide the numerical goals which water resource managers can use to adequately manage and protect aquatic ecosystems. Various methods which have been developed and used internationally to derive such guidelines are discussed. Acute toxicity tests were conducted using two inorganic salts, NaCl and Na₂SO₄. Field collected, indigenous, freshwater macroinvertebrates were used as tests organisms. Data generated from these tests contributed to the expansion of the currently limited toxicological database of response data for indigenous organisms and the suitability of using such organisms for future testing was discussed. Salt sensitivities of indigenous freshwater invertebrates were compared those of species sourced from an international toxicological database and were found to have similar ranges of tolerances to NaCl and Na₂SO₄. Species sensitivity distributions (SSDs), a method of data extrapolation, were derived using different types of toxicological data, and hence different guideline values or protective concentrations were derived. These concentrations were equated to boundary values for South Africa’s ecological Reserve categories, which are used to describe degrees of health for aquatic ecosystems. Provisional results suggest that using only acute toxicity data in guideline derivation provides ecosystem protection that is under-protective. Chronic toxicity data, which include endpoints other than mortality, provide the most realistic environmental protection but lack data confidence due to small sample sizes (acute tests are more readily conducted than chronic tests). The potential contribution of sub-chronic data to guideline derivation is highlighted as these data are more readily extrapolated to chronic endpoints than acute data and sub-chronic tests are not as complex and demanding to conduct as chronic tests.
- Full Text: