A new role for the non-aligned movement in a post-cold war era
- Authors: Chetty, Mahesh
- Date: 2000
- Subjects: Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2767 , http://hdl.handle.net/10962/d1002977 , Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Description: With the disappearance of the superpower conflict that characterised the Cold War era, many observers have begun to question whether the Non-Aligned Movement (NAM) has a role to play in the post Cold War era. However the emergence of a number of issues on the international agenda, such as United Nations peacekeeping operations, global environmental issues and an increasing unwillingness on the part of the major economic powers to abide by GATT/WTO rules, have increasingly become of concern to non-aligned states. However whilst the United States has recognised that these issues require leadership in dealing with them, it has not been willing to supply that leadership. It shall therefore be argued that the changing nature of hegemony in world politics has set conditions that allow non-aligned middle powers and institutions greater scope for action and influence. The emergence of these issues has provided a scope for non-aligned middle powers, acting in accordance with their interests to play alternate leadership roles within an expanded scope for institutions, such as organisations, regimes and multilateralism, in addressing the interests of non-aligned states. Firstly in looking at an expanded role for organisations, the United States has increasingly been unwilling to play a leadership role within UN peacekeeping operations. The continuing importance of the neutrality of UN peacekeeping operations has provided a scope for nonaligned middle powers to play a burden-sharing role with the great powers in addressing the concerns of non-aligned states with regard to these operations. Secondly in looking at an expanded scope for regimes, the emergence of a regime in the issue of ozone depletion may provide a foundation to analyse how non-aligned middle powers may play a bridge-building role between North and South in the issue of climate change. Middle powers could therefore play this role in the absence of United States leadership within this issue. Thirdly, the role of the Cairns Group within the Uruguay Round in addressing non-aligned states’ interests of maintaining stable agricultural trade, can be seen as a model of small group multilateralism in bridging the divide between the major powers in issue specific areas.
- Full Text:
- Date Issued: 2000
- Authors: Chetty, Mahesh
- Date: 2000
- Subjects: Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2767 , http://hdl.handle.net/10962/d1002977 , Non-Aligned Movement , Nonalignment , Nonalignment -- Developing countries , International police
- Description: With the disappearance of the superpower conflict that characterised the Cold War era, many observers have begun to question whether the Non-Aligned Movement (NAM) has a role to play in the post Cold War era. However the emergence of a number of issues on the international agenda, such as United Nations peacekeeping operations, global environmental issues and an increasing unwillingness on the part of the major economic powers to abide by GATT/WTO rules, have increasingly become of concern to non-aligned states. However whilst the United States has recognised that these issues require leadership in dealing with them, it has not been willing to supply that leadership. It shall therefore be argued that the changing nature of hegemony in world politics has set conditions that allow non-aligned middle powers and institutions greater scope for action and influence. The emergence of these issues has provided a scope for non-aligned middle powers, acting in accordance with their interests to play alternate leadership roles within an expanded scope for institutions, such as organisations, regimes and multilateralism, in addressing the interests of non-aligned states. Firstly in looking at an expanded role for organisations, the United States has increasingly been unwilling to play a leadership role within UN peacekeeping operations. The continuing importance of the neutrality of UN peacekeeping operations has provided a scope for nonaligned middle powers to play a burden-sharing role with the great powers in addressing the concerns of non-aligned states with regard to these operations. Secondly in looking at an expanded scope for regimes, the emergence of a regime in the issue of ozone depletion may provide a foundation to analyse how non-aligned middle powers may play a bridge-building role between North and South in the issue of climate change. Middle powers could therefore play this role in the absence of United States leadership within this issue. Thirdly, the role of the Cairns Group within the Uruguay Round in addressing non-aligned states’ interests of maintaining stable agricultural trade, can be seen as a model of small group multilateralism in bridging the divide between the major powers in issue specific areas.
- Full Text:
- Date Issued: 2000
Towards an understanding of the role of commercialisation in programming at the Malawi Broadcasting Corporation from 1995 to 1998 : a case study
- Chikunkhuzeni, Francis Chim'ndomo
- Authors: Chikunkhuzeni, Francis Chim'ndomo
- Date: 2000
- Subjects: Malawi Broadcasting Corporation , Broadcasting -- Malawi , Public broadcasting -- Malawi , Broadcasting policy -- Malawi , Broadcast advertising -- Malawi
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3422 , http://hdl.handle.net/10962/d1002875 , Malawi Broadcasting Corporation , Broadcasting -- Malawi , Public broadcasting -- Malawi , Broadcasting policy -- Malawi , Broadcast advertising -- Malawi
- Description: Competition in many market-driven media systems in advanced industrial countries can sometimes compromise traditional public service broadcast values such as programming for diversity, citizenship, minority interests and national identity. This study investigates the presence and effects of commercial-logic in a state-owned broadcaster in a developing country: the Malawi Broadcasting Corporation. Using indepth interviews and analysis of records on finance and programme schedules, the study finds overwhelming indicators of the presence of commercial logic, not driven by competition, but a commitment to provide a public service under deteriorating financial conditions. Distinguishing between the impacts of advertising and sponsorship markets on media output, the study finds contradictory effects of commercialisation. Some effects confirm some of the adverse effects of commercialisation such as heavy sponsorinfluence on programme content, self-censorship among programme producers who avoid injuring sponsors and producers paying more attention to sponsored programmes at the expense ofthe quality of some non-sponsored public service programmes. However, effects are not always contrary to public service broadcasting but may Indeed reinforce such broadcasting. Commercialisation in some instances has led to the sustenance of a range of non-sponsored public service programmes including programmes to promote culture and civic rights. In general, this study highlights the need to focus on what is realistically possible within the dynamics of the Malawi Society as a precondition for a proactive and elaborate strategy for commercialisation ofthe country's public broadcaster.
- Full Text:
- Date Issued: 2000
- Authors: Chikunkhuzeni, Francis Chim'ndomo
- Date: 2000
- Subjects: Malawi Broadcasting Corporation , Broadcasting -- Malawi , Public broadcasting -- Malawi , Broadcasting policy -- Malawi , Broadcast advertising -- Malawi
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3422 , http://hdl.handle.net/10962/d1002875 , Malawi Broadcasting Corporation , Broadcasting -- Malawi , Public broadcasting -- Malawi , Broadcasting policy -- Malawi , Broadcast advertising -- Malawi
- Description: Competition in many market-driven media systems in advanced industrial countries can sometimes compromise traditional public service broadcast values such as programming for diversity, citizenship, minority interests and national identity. This study investigates the presence and effects of commercial-logic in a state-owned broadcaster in a developing country: the Malawi Broadcasting Corporation. Using indepth interviews and analysis of records on finance and programme schedules, the study finds overwhelming indicators of the presence of commercial logic, not driven by competition, but a commitment to provide a public service under deteriorating financial conditions. Distinguishing between the impacts of advertising and sponsorship markets on media output, the study finds contradictory effects of commercialisation. Some effects confirm some of the adverse effects of commercialisation such as heavy sponsorinfluence on programme content, self-censorship among programme producers who avoid injuring sponsors and producers paying more attention to sponsored programmes at the expense ofthe quality of some non-sponsored public service programmes. However, effects are not always contrary to public service broadcasting but may Indeed reinforce such broadcasting. Commercialisation in some instances has led to the sustenance of a range of non-sponsored public service programmes including programmes to promote culture and civic rights. In general, this study highlights the need to focus on what is realistically possible within the dynamics of the Malawi Society as a precondition for a proactive and elaborate strategy for commercialisation ofthe country's public broadcaster.
- Full Text:
- Date Issued: 2000
Profile of paediatric psychosocial disorders in Frere Hospital and analysis of associated patterns of referrals
- Authors: Chukwuemeka, Gregory Adjuba
- Date: 2000
- Subjects: Child psychopathology , Frere Hospital
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2949 , http://hdl.handle.net/10962/d1002458 , Child psychopathology , Frere Hospital
- Description: The profile of psychosocial disorders in children and the attendant patterns of referrals and health communication, were investigated within the context of a tertiary referral centre in the Eastern Cape Province. Literature on childhood disorders points to a high level of functional and substance related disorders in technologically developed countries of Europe and North America, in contrast to the developing countries of Asia and Africa, where the burden of infectious diseases and disorders of deprivation and lack still predominate in the profile of psychosocial disorders in children. In South Africa however, there is almost non-existent research on clinical psychosocial disorders profile and the research sets out to be an exploratory study in this area. A combination design was employed in which interviews and observations complemented a primarily quantitative descriptive cross sectional analysis of hospitalcase records. A pilot study was performed using an information gathering questionnaire and interviews, with findings subsequently explored in the main study. The International Classification of Diseases (ICD-10) (WHO, 1992) diagnostic categories were used to create a profile of all ailments in the paediatric unit. Psychosocial disorders both in terms of aetiology and illness course, can be viewed from the perspective of socialadjustment and functioning (in which there is a potential role of social factors as provoking, causal or modifying factors) (Williams &Clare, 1979); and the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) (American Psychiatric Association,1994) criteria was used to create the profile of these disorders in the paediatric unit at Frere Hospital which accounted for 45% of the ailments managed in one year. The derived profile is a picture in between the profile found in technologically advanced countries, and developing countries. While the infection burden and malnutrition appear to be readily contained or curtailed, there appears to be a serious problem with access to health care services which manifest especially at the level of perinatal events, with resultant high level of hypoxic brain damage and consequently mental retardation and varying levels of impairment or disability. These medical consequences in turn are fundamentally psychosocial, requiring psychosocial care with heavy reliance on strategic communication and referrals. The referrals in respect of psychosocial disorders are mainly at primary care level revolving around local health care clinics, private clinics, special schools and rehabilitation centres.
- Full Text:
- Date Issued: 2000
- Authors: Chukwuemeka, Gregory Adjuba
- Date: 2000
- Subjects: Child psychopathology , Frere Hospital
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2949 , http://hdl.handle.net/10962/d1002458 , Child psychopathology , Frere Hospital
- Description: The profile of psychosocial disorders in children and the attendant patterns of referrals and health communication, were investigated within the context of a tertiary referral centre in the Eastern Cape Province. Literature on childhood disorders points to a high level of functional and substance related disorders in technologically developed countries of Europe and North America, in contrast to the developing countries of Asia and Africa, where the burden of infectious diseases and disorders of deprivation and lack still predominate in the profile of psychosocial disorders in children. In South Africa however, there is almost non-existent research on clinical psychosocial disorders profile and the research sets out to be an exploratory study in this area. A combination design was employed in which interviews and observations complemented a primarily quantitative descriptive cross sectional analysis of hospitalcase records. A pilot study was performed using an information gathering questionnaire and interviews, with findings subsequently explored in the main study. The International Classification of Diseases (ICD-10) (WHO, 1992) diagnostic categories were used to create a profile of all ailments in the paediatric unit. Psychosocial disorders both in terms of aetiology and illness course, can be viewed from the perspective of socialadjustment and functioning (in which there is a potential role of social factors as provoking, causal or modifying factors) (Williams &Clare, 1979); and the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) (American Psychiatric Association,1994) criteria was used to create the profile of these disorders in the paediatric unit at Frere Hospital which accounted for 45% of the ailments managed in one year. The derived profile is a picture in between the profile found in technologically advanced countries, and developing countries. While the infection burden and malnutrition appear to be readily contained or curtailed, there appears to be a serious problem with access to health care services which manifest especially at the level of perinatal events, with resultant high level of hypoxic brain damage and consequently mental retardation and varying levels of impairment or disability. These medical consequences in turn are fundamentally psychosocial, requiring psychosocial care with heavy reliance on strategic communication and referrals. The referrals in respect of psychosocial disorders are mainly at primary care level revolving around local health care clinics, private clinics, special schools and rehabilitation centres.
- Full Text:
- Date Issued: 2000
Physiological, perceptual and other performance decrements in combat related tasks following prolonged heavy-load marching
- Authors: Clark, Lisa Anne
- Date: 2000
- Subjects: Performance -- Psychological aspects , Performance standards -- Case studies , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Marching -- Physiological aspects , Soldiers -- Job stress
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5130 , http://hdl.handle.net/10962/d1005209 , Performance -- Psychological aspects , Performance standards -- Case studies , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Marching -- Physiological aspects , Soldiers -- Job stress
- Description: In response to challenging situations physiological and psychological adaptations result in elevated levels of arousal and when these levels are 'optimal' performance is enhanced. There are however, limitations to the amount of physiological and mental stimulation one can tolerate, with cumulative fatigue effects being the outcome when stressful conditions are imposed on the individual over an extended period of time. As a result of the extreme physical and cognitive demands placed on military forces while in combat, with soldiers being thrust into battle and required to make critical life-or-death determining decisions followed by appropriate motor responses, the physical and psychological capabilities of the troops are pushed to maximal limits, often resulting in undesirable decrements in physical and mental performance, with consequential human and materiel losses. Thirty-two soldiers participated in a battery of combat-related field and laboratory tests, first under 'normal' conditions with no prior physical activity and then immediately after the participation of an intensive bout of exercise. Physiological and perceptual responses plus standard of performance were measured at various stages of testing. Results of the Rating of Perceived Exertion (RPE), Body Discomfort Scale and heart rate responses revealed significantly higher levels of psychophysical strai,n in response to the strenuous physical activity. Despite these findings, the electromyographic (EMG) activity and efficiency of the combat-related skills were not negatively affected. Rather, nominal improvements in post-activity performance were noted, specifically response time, and this was attributed to elevated arousal and activation as a result of the exercise that was of sufficient duration to enhance arousal without imposing long term cumulative fatigue effects.
- Full Text:
- Date Issued: 2000
- Authors: Clark, Lisa Anne
- Date: 2000
- Subjects: Performance -- Psychological aspects , Performance standards -- Case studies , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Marching -- Physiological aspects , Soldiers -- Job stress
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5130 , http://hdl.handle.net/10962/d1005209 , Performance -- Psychological aspects , Performance standards -- Case studies , Exercise -- Physiological aspects , Exercise -- Psychological aspects , Marching -- Physiological aspects , Soldiers -- Job stress
- Description: In response to challenging situations physiological and psychological adaptations result in elevated levels of arousal and when these levels are 'optimal' performance is enhanced. There are however, limitations to the amount of physiological and mental stimulation one can tolerate, with cumulative fatigue effects being the outcome when stressful conditions are imposed on the individual over an extended period of time. As a result of the extreme physical and cognitive demands placed on military forces while in combat, with soldiers being thrust into battle and required to make critical life-or-death determining decisions followed by appropriate motor responses, the physical and psychological capabilities of the troops are pushed to maximal limits, often resulting in undesirable decrements in physical and mental performance, with consequential human and materiel losses. Thirty-two soldiers participated in a battery of combat-related field and laboratory tests, first under 'normal' conditions with no prior physical activity and then immediately after the participation of an intensive bout of exercise. Physiological and perceptual responses plus standard of performance were measured at various stages of testing. Results of the Rating of Perceived Exertion (RPE), Body Discomfort Scale and heart rate responses revealed significantly higher levels of psychophysical strai,n in response to the strenuous physical activity. Despite these findings, the electromyographic (EMG) activity and efficiency of the combat-related skills were not negatively affected. Rather, nominal improvements in post-activity performance were noted, specifically response time, and this was attributed to elevated arousal and activation as a result of the exercise that was of sufficient duration to enhance arousal without imposing long term cumulative fatigue effects.
- Full Text:
- Date Issued: 2000
Handheld infrared CO2 gas detector
- Authors: Coetzee, George
- Date: 2000
- Subjects: Gas-detectors , Infrared detectors , Water quality -- Measurement
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10807 , http://hdl.handle.net/10948/28 , Gas-detectors , Infrared detectors , Water quality -- Measurement
- Description: A handheld InfraRed (IR) Carbon Dioxide (CO2) gas detector was developed and used to carry out a study of water and urine samples in South Africa. The details of the model and the results of the study are discussed here. The overseas markets are not geared for the current South African conditions. Use is made of components that can be obtained locally. Imported components are very expensive and should an imported model be damaged, it has to be returned overseas to be repaired. As an illustration of this technology it was decided to perform research in water technology and then develope a handheld Infrared CO2 gas detector based prototype which would: highlight the benefits of using handheld IR CO2 gas detectors; be built locally; be powered by a 12 Volt supply; be very easy to maintain; and be cost effective. Experimental results on the accuracy and stability of the instrument formed part of this study. The IR CO2 Gas detector that was developed was used throughout the project as a prototype and testing vehicle for numerous designs. It proved to be superior to the current imported commercial instruments in terms of size, cost effectiveness and user friendliness. A further advantage of the instrument is its robustness.
- Full Text:
- Date Issued: 2000
- Authors: Coetzee, George
- Date: 2000
- Subjects: Gas-detectors , Infrared detectors , Water quality -- Measurement
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10807 , http://hdl.handle.net/10948/28 , Gas-detectors , Infrared detectors , Water quality -- Measurement
- Description: A handheld InfraRed (IR) Carbon Dioxide (CO2) gas detector was developed and used to carry out a study of water and urine samples in South Africa. The details of the model and the results of the study are discussed here. The overseas markets are not geared for the current South African conditions. Use is made of components that can be obtained locally. Imported components are very expensive and should an imported model be damaged, it has to be returned overseas to be repaired. As an illustration of this technology it was decided to perform research in water technology and then develope a handheld Infrared CO2 gas detector based prototype which would: highlight the benefits of using handheld IR CO2 gas detectors; be built locally; be powered by a 12 Volt supply; be very easy to maintain; and be cost effective. Experimental results on the accuracy and stability of the instrument formed part of this study. The IR CO2 Gas detector that was developed was used throughout the project as a prototype and testing vehicle for numerous designs. It proved to be superior to the current imported commercial instruments in terms of size, cost effectiveness and user friendliness. A further advantage of the instrument is its robustness.
- Full Text:
- Date Issued: 2000
Outsourcing for competitive advantage : an evaluation of an owner driver proposition in a South African removals company
- Authors: Coleman, Belinda
- Date: 2000
- Subjects: Contracting out -- South Africa , Storage and removal trade -- Subcontracting -- South Africa , Trucking -- South Africa , Benchmarking (Management) -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:11002 , http://hdl.handle.net/10948/d1015540
- Description: The aim of the research was to assess what competitive advantage a Removals company could expect to gain by outsourcing its driver function to owner drivers. An extensive literature review identified key outsourcing issues. The literature was related to a case study of Stuttaford Van Lines (SVL), a company that is experiencing problems with its current independent contractor driver arrangements and that needs to review its outsourcing decision. In order to learn from best practice in the field of outsourcing to owner drivers, a benchmarking exercise was undertaken at South African Breweries (SAB). The benchmarking exercise identified six key issues that contributed to the success of the SAB owner driver scheme. These points, together with others identified from the literature, were integrated into a recommended outsourcing implementation process for SVL. The research found that it is possible for SVL to outsource the driver function to owner drivers and that such a scheme can be expected to improve customer service levels. The success of the scheme will depend on the selection of the drivers and how effectively it is managed. It was found that it would not be profitable for SVL to outsource to owner drivers using the compensation model proposed. Cost reduction is however only one of the factors to consider in an outsourcing decision.
- Full Text:
- Date Issued: 2000
- Authors: Coleman, Belinda
- Date: 2000
- Subjects: Contracting out -- South Africa , Storage and removal trade -- Subcontracting -- South Africa , Trucking -- South Africa , Benchmarking (Management) -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:11002 , http://hdl.handle.net/10948/d1015540
- Description: The aim of the research was to assess what competitive advantage a Removals company could expect to gain by outsourcing its driver function to owner drivers. An extensive literature review identified key outsourcing issues. The literature was related to a case study of Stuttaford Van Lines (SVL), a company that is experiencing problems with its current independent contractor driver arrangements and that needs to review its outsourcing decision. In order to learn from best practice in the field of outsourcing to owner drivers, a benchmarking exercise was undertaken at South African Breweries (SAB). The benchmarking exercise identified six key issues that contributed to the success of the SAB owner driver scheme. These points, together with others identified from the literature, were integrated into a recommended outsourcing implementation process for SVL. The research found that it is possible for SVL to outsource the driver function to owner drivers and that such a scheme can be expected to improve customer service levels. The success of the scheme will depend on the selection of the drivers and how effectively it is managed. It was found that it would not be profitable for SVL to outsource to owner drivers using the compensation model proposed. Cost reduction is however only one of the factors to consider in an outsourcing decision.
- Full Text:
- Date Issued: 2000
Settler women's experiences of fear, illness and isolation, with particular reference to the Eastern Cape Frontier, 1820-1890
- Authors: Dampier, Helen
- Date: 2000
- Subjects: Women -- South Africa -- History , Women -- South Africa -- Eastern Cape -- Social conditions , Women -- South Africa -- Eastern Cape -- History , British settlers of 1820 (South Africa) , Frontier and pioneer life -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2537 , http://hdl.handle.net/10962/d1002389 , Women -- South Africa -- History , Women -- South Africa -- Eastern Cape -- Social conditions , Women -- South Africa -- Eastern Cape -- History , British settlers of 1820 (South Africa) , Frontier and pioneer life -- South Africa
- Description: This thesis is an exploration of diaries and letters written by middle-class English-speaking settler women living on the Eastern Cape frontier between 1820 and 1890. By according primacy to these women’s experiences and perceptions, it aims for a greater understanding of women’s encounters with the frontier, and how these were articulated in their personal writing. An emphasis on the recurrent themes of ill-health, fearfulness and solitude undermines the popular myth of the brave, conquering, invincible pioneers which dominates settler historiography to date. The tensions felt by white women living on the frontier disrupted their identities as middle-class Victorian ‘ladies’, and as a result these women either constantly re-established a sense of self, or absorbed some aspects of the Eastern Cape, and thus redefined themselves. Settler women’s experiences of the frontier changed little during the seventy year period spanned by this study, indicating that frontier life led to a rigidification and reinforcement of old, familiar values and behaviours. Rather than adapting to and embracing their new surroundings, settler women sought to duplicate accepted, conventional Victorian ideals and customs. White Victorian women identified themselves as refined, civilized, moral and respectable, and perceived Africa and Africans as untamed, immoral, uncivilized and threatening. To keep these menacing, destabilizing forces at bay, settler women attempted to recreate ‘home’ in the Eastern Cape; to domesticate the frontier by rendering it as familiar and predictable as possible. The fear, illness and solitariness that characterise settler women’s personal writings manifest their attempts to eliminate alienating difference, and record their refusal to truly engage with the frontier landscape and its inhabitants.
- Full Text:
- Date Issued: 2000
- Authors: Dampier, Helen
- Date: 2000
- Subjects: Women -- South Africa -- History , Women -- South Africa -- Eastern Cape -- Social conditions , Women -- South Africa -- Eastern Cape -- History , British settlers of 1820 (South Africa) , Frontier and pioneer life -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2537 , http://hdl.handle.net/10962/d1002389 , Women -- South Africa -- History , Women -- South Africa -- Eastern Cape -- Social conditions , Women -- South Africa -- Eastern Cape -- History , British settlers of 1820 (South Africa) , Frontier and pioneer life -- South Africa
- Description: This thesis is an exploration of diaries and letters written by middle-class English-speaking settler women living on the Eastern Cape frontier between 1820 and 1890. By according primacy to these women’s experiences and perceptions, it aims for a greater understanding of women’s encounters with the frontier, and how these were articulated in their personal writing. An emphasis on the recurrent themes of ill-health, fearfulness and solitude undermines the popular myth of the brave, conquering, invincible pioneers which dominates settler historiography to date. The tensions felt by white women living on the frontier disrupted their identities as middle-class Victorian ‘ladies’, and as a result these women either constantly re-established a sense of self, or absorbed some aspects of the Eastern Cape, and thus redefined themselves. Settler women’s experiences of the frontier changed little during the seventy year period spanned by this study, indicating that frontier life led to a rigidification and reinforcement of old, familiar values and behaviours. Rather than adapting to and embracing their new surroundings, settler women sought to duplicate accepted, conventional Victorian ideals and customs. White Victorian women identified themselves as refined, civilized, moral and respectable, and perceived Africa and Africans as untamed, immoral, uncivilized and threatening. To keep these menacing, destabilizing forces at bay, settler women attempted to recreate ‘home’ in the Eastern Cape; to domesticate the frontier by rendering it as familiar and predictable as possible. The fear, illness and solitariness that characterise settler women’s personal writings manifest their attempts to eliminate alienating difference, and record their refusal to truly engage with the frontier landscape and its inhabitants.
- Full Text:
- Date Issued: 2000
The representation of "South Africanness" in the locally produced television production, Generations
- Authors: Dentlinger, Lindsay
- Date: 2000
- Subjects: Television soap operas -- South Africa , National characteristics, South African, In Literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3425 , http://hdl.handle.net/10962/d1002878 , Television soap operas -- South Africa , National characteristics, South African, In Literature
- Description: The aim of this study is to analyse selected episodes of the locally produced television programme Generations, in order to identify specific ways in which the programme seeks to forge a South African identity, and in so doing, 'flag' our nationhood as South Africans. These elements of 'South Africanness' are broadly defined as connections to a South African way of life, context, values and experiences. Generations is a programme produced under South African broadcasting local content provisions. These provisions arise out of the need, inter alia, to reflect the identity and multi-cultural nature of South Africa in order to foster 'national identity' and 'national culture'. These elements of 'South Africanness' are extracted through a genre and ideological analysis of selected sample episodes, taking into consideration the theoretical frameworks of the politics of representation and identity. The production context of, and representations made, in Generations, are found to be situated largely within the context of the South African discourses of the ‘rainbow nation', 'African renaissance' and 'black economic empowerment'. The analysis concludes that through the various categories of representations of 'South Africanness' in the selected episodes of Generations, specific instances of identity, that of national culture and national identity are formed.
- Full Text:
- Date Issued: 2000
The representation of "South Africanness" in the locally produced television production, Generations
- Authors: Dentlinger, Lindsay
- Date: 2000
- Subjects: Television soap operas -- South Africa , National characteristics, South African, In Literature
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3425 , http://hdl.handle.net/10962/d1002878 , Television soap operas -- South Africa , National characteristics, South African, In Literature
- Description: The aim of this study is to analyse selected episodes of the locally produced television programme Generations, in order to identify specific ways in which the programme seeks to forge a South African identity, and in so doing, 'flag' our nationhood as South Africans. These elements of 'South Africanness' are broadly defined as connections to a South African way of life, context, values and experiences. Generations is a programme produced under South African broadcasting local content provisions. These provisions arise out of the need, inter alia, to reflect the identity and multi-cultural nature of South Africa in order to foster 'national identity' and 'national culture'. These elements of 'South Africanness' are extracted through a genre and ideological analysis of selected sample episodes, taking into consideration the theoretical frameworks of the politics of representation and identity. The production context of, and representations made, in Generations, are found to be situated largely within the context of the South African discourses of the ‘rainbow nation', 'African renaissance' and 'black economic empowerment'. The analysis concludes that through the various categories of representations of 'South Africanness' in the selected episodes of Generations, specific instances of identity, that of national culture and national identity are formed.
- Full Text:
- Date Issued: 2000
Searching for new relevance in the 1990s: the Organization of African Unity as an instrument of conflict resolution
- Authors: Dlamini, Thandeka Lungile
- Date: 2000
- Subjects: Organization of African Unity , Africa -- Foreign relations , Conflict management -- Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2770 , http://hdl.handle.net/10962/d1002980 , Organization of African Unity , Africa -- Foreign relations , Conflict management -- Africa
- Description: The 1960's and the 1970's marked a great Pan-African movement in Africa, that saw the liberation of most African states. This Pan-African movement, was spearheaded by a quest to unite Africa, and to abate foreign occupation. Amidst the spirit of unity, lay a promise of an organization that would embody the hopes and aspirations of a continent undergoing a re-birth; a progression towards self-determination, economic development and integration, and the maintenance of peace. Therefore, the inception ofthe Organization of African Unity (OAD) was not only a symbol of a unifying force for Africans, but a diplomatic platform that would promote African needs on the international arena. In effect the OAU, at its inception, was for specific ideals that would guarantee liberation and unity of African states. The outcome of these ideals would be greater regional economic integration and the achievement of peace and stability. These ideals mirrored the structural definition of regional organization, with the inclusion of a Commission for Mediation Arbitration and Conciliation under the OAU Charter, to handle disputes among member states. However, the mere fact that this commission lacked the political wherewithal to resolve conflicts, by its sheer lack of a standing peacekeeping force, contributed to the inefficiency of the organization to play an effective role in conflict management. This study attempts to examine the role ofthe OAU in settling disputes. The study sought to accomplish this, in the following manner. Firstly, an investigation into the nature of conflict and why it persists in Africa was conducted. Further, an examination ofthe tools that practitioners utilize not only to study conflict, but to prevent, manage and resolve it, was done. During the investigation it was found that, although the OAU's greatest successes have come from preventive diplomacy, its structural foundations limit the capabilities of the organization to become more relevant. The Charter of the OAU alludes vaguely to the settlement of disputes, but without an executive political decision-making body able to deploy peacekeepers, its principles are largely meaningless. Amidst the growing concerns, the OAU as a matter of survival, developed initiatives it hopes will make it more effective and relevant. The focus ofthe study was the evolving role ofthe OAU, from its inception to its new role as an instrument of conflict resolution. Most of the scholarly work conducted on the OAU, is concerned with depicting a terminal organization, with little or no hope of surviving. Little emphasis is placed on prescribing remedies on how to improve and restructure the organization. The findings included, inter alia, that the organization is faced with enormous challenges, as the sources of conflict are varied and complex. Africa is now the landscape of collapsed states, economic stagnation, environmental degradation, disease and chronic conflicts. The OAU shoulders much ofthe responsibility for not sanctioning governments that contribute to the decay and suffering of the African peoples. Most ofthe criticism of the OAU, stem from the inability of the organization to play an effective role in resolving conflicts in Africa. Most of Africa's conflicts stem from a lack of political legitimacy, lack of democratic institutions, uneven distribution of resources, ethnic tensions and economic stagnation. Until such problems are addressed, Africa will continue to host the world's deadliest conflicts.
- Full Text:
- Date Issued: 2000
- Authors: Dlamini, Thandeka Lungile
- Date: 2000
- Subjects: Organization of African Unity , Africa -- Foreign relations , Conflict management -- Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2770 , http://hdl.handle.net/10962/d1002980 , Organization of African Unity , Africa -- Foreign relations , Conflict management -- Africa
- Description: The 1960's and the 1970's marked a great Pan-African movement in Africa, that saw the liberation of most African states. This Pan-African movement, was spearheaded by a quest to unite Africa, and to abate foreign occupation. Amidst the spirit of unity, lay a promise of an organization that would embody the hopes and aspirations of a continent undergoing a re-birth; a progression towards self-determination, economic development and integration, and the maintenance of peace. Therefore, the inception ofthe Organization of African Unity (OAD) was not only a symbol of a unifying force for Africans, but a diplomatic platform that would promote African needs on the international arena. In effect the OAU, at its inception, was for specific ideals that would guarantee liberation and unity of African states. The outcome of these ideals would be greater regional economic integration and the achievement of peace and stability. These ideals mirrored the structural definition of regional organization, with the inclusion of a Commission for Mediation Arbitration and Conciliation under the OAU Charter, to handle disputes among member states. However, the mere fact that this commission lacked the political wherewithal to resolve conflicts, by its sheer lack of a standing peacekeeping force, contributed to the inefficiency of the organization to play an effective role in conflict management. This study attempts to examine the role ofthe OAU in settling disputes. The study sought to accomplish this, in the following manner. Firstly, an investigation into the nature of conflict and why it persists in Africa was conducted. Further, an examination ofthe tools that practitioners utilize not only to study conflict, but to prevent, manage and resolve it, was done. During the investigation it was found that, although the OAU's greatest successes have come from preventive diplomacy, its structural foundations limit the capabilities of the organization to become more relevant. The Charter of the OAU alludes vaguely to the settlement of disputes, but without an executive political decision-making body able to deploy peacekeepers, its principles are largely meaningless. Amidst the growing concerns, the OAU as a matter of survival, developed initiatives it hopes will make it more effective and relevant. The focus ofthe study was the evolving role ofthe OAU, from its inception to its new role as an instrument of conflict resolution. Most of the scholarly work conducted on the OAU, is concerned with depicting a terminal organization, with little or no hope of surviving. Little emphasis is placed on prescribing remedies on how to improve and restructure the organization. The findings included, inter alia, that the organization is faced with enormous challenges, as the sources of conflict are varied and complex. Africa is now the landscape of collapsed states, economic stagnation, environmental degradation, disease and chronic conflicts. The OAU shoulders much ofthe responsibility for not sanctioning governments that contribute to the decay and suffering of the African peoples. Most ofthe criticism of the OAU, stem from the inability of the organization to play an effective role in resolving conflicts in Africa. Most of Africa's conflicts stem from a lack of political legitimacy, lack of democratic institutions, uneven distribution of resources, ethnic tensions and economic stagnation. Until such problems are addressed, Africa will continue to host the world's deadliest conflicts.
- Full Text:
- Date Issued: 2000
Strike comparison of the compositional variations of the lower group and middle group chromitite seams of the critical zone, Western Bushveld complex
- Authors: Doig, Heather Leslie
- Date: 2000
- Subjects: Chromite -- South Africa , Geology -- South Africa , Mineralogy -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5005 , http://hdl.handle.net/10962/d1005618
- Description: The variations in the composition, specifically the Cr20 S content and the Cr:Fe ratio, and the morphology of the Lower Group (LG) and Middle Group (MG) chromitite seams of the Critical Zone (CZ) across the western Bushveld Complex, including the Ruighoek and Brits sections, is investigated by means of whole-rock chemical data, both major and trace elements analysis, XRD and electron microprobe data. As a result ofthe paucity of exposed or developed LG1 - LG5 chromitite seams in the western Bushveld Complex, this study is confined to the investigation of the compositional variations of the LG6 to MG4 chromitite seams. In only one section, the Ruighoek section, was the entire succession of chromitite seams, from the LG1 - MG4, exposed. The silicate host rocks from the LG6 pyroxenite footwall to the collar of the CC2 drillcore (lower uCZ) in the Rustenburg section were sampled. This study reviews the compositional trends of the silicate host rocks, as the compositional variations of the chromitite seams reflect the chemical evolution of the host cumulate environment and, to a lesser degree, the composition onhe interstitial mineral phases in the chromitite seams. The compositional variations of the LG and MG chromitite seams are attributed to the compositional contrast between the replenishing magma and the resident magma. The chemical trends of the LG and MG chromitite layers and the host cumUlate rOCKS do not support the existence of two compositionalfy dissimilar magmas in the CZ, rather the cyclic layering of the CZ and the chemical variations of the chromitite seams are attributed to the mixing of primitive magma with the resident magma, both of which have essentially similar compositions. The compositional variations of the LG and MG chromitite seams along strike away from the supposed feeder site (Union section) to the distal facies (Brits section) are attributed to the advanced compositional contrast between the resident magma and the replenishing primitive magma pulses. The CZ is characterized by reversals in fractionation trends and this is attributed to the compositional evolution of the parental magma and not to the replenishment of the resident magma by influxes of grossly dissimilar magma compositions. The Cr20 S content and the Cr:Fe ratio of the MG chromitite layers increase from the Ruighoek (near proximal) section to the Brits section (distal facies). This is attributed to the advanced compositional contrasts between the resident magma and the replenishing primitive magma. In contrast, the Cr20 3 content and Cr:Fe ratios ofthe LG6 and LG8a chromitite seams decreases eastwards from the Ruighoek section. The average Cr:Fe ratio for the western Bushveld Complex is between 1.5 and\2.0, nonetheless, a progressively lower Cr:Fe ratio is noted from the LG1 chromitite up through to the MG4 chromitite seam in the Ruighoek section. tn the LG2 - LG4 chromitite interval a deviation to higher.lratios is encountered. A progressive substitution of Cr by AT and Fe in the Cr-spinel crystal lattice characterizes the chromitite succession from the LG1 seam up through the chromitite succession to MG4. The petrogeneSiS of the chromitite seams of the CZ is attributed to magma mixing and fractional crystallization of a single magma type.
- Full Text:
- Date Issued: 2000
- Authors: Doig, Heather Leslie
- Date: 2000
- Subjects: Chromite -- South Africa , Geology -- South Africa , Mineralogy -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5005 , http://hdl.handle.net/10962/d1005618
- Description: The variations in the composition, specifically the Cr20 S content and the Cr:Fe ratio, and the morphology of the Lower Group (LG) and Middle Group (MG) chromitite seams of the Critical Zone (CZ) across the western Bushveld Complex, including the Ruighoek and Brits sections, is investigated by means of whole-rock chemical data, both major and trace elements analysis, XRD and electron microprobe data. As a result ofthe paucity of exposed or developed LG1 - LG5 chromitite seams in the western Bushveld Complex, this study is confined to the investigation of the compositional variations of the LG6 to MG4 chromitite seams. In only one section, the Ruighoek section, was the entire succession of chromitite seams, from the LG1 - MG4, exposed. The silicate host rocks from the LG6 pyroxenite footwall to the collar of the CC2 drillcore (lower uCZ) in the Rustenburg section were sampled. This study reviews the compositional trends of the silicate host rocks, as the compositional variations of the chromitite seams reflect the chemical evolution of the host cumulate environment and, to a lesser degree, the composition onhe interstitial mineral phases in the chromitite seams. The compositional variations of the LG and MG chromitite seams are attributed to the compositional contrast between the replenishing magma and the resident magma. The chemical trends of the LG and MG chromitite layers and the host cumUlate rOCKS do not support the existence of two compositionalfy dissimilar magmas in the CZ, rather the cyclic layering of the CZ and the chemical variations of the chromitite seams are attributed to the mixing of primitive magma with the resident magma, both of which have essentially similar compositions. The compositional variations of the LG and MG chromitite seams along strike away from the supposed feeder site (Union section) to the distal facies (Brits section) are attributed to the advanced compositional contrast between the resident magma and the replenishing primitive magma pulses. The CZ is characterized by reversals in fractionation trends and this is attributed to the compositional evolution of the parental magma and not to the replenishment of the resident magma by influxes of grossly dissimilar magma compositions. The Cr20 S content and the Cr:Fe ratio of the MG chromitite layers increase from the Ruighoek (near proximal) section to the Brits section (distal facies). This is attributed to the advanced compositional contrasts between the resident magma and the replenishing primitive magma. In contrast, the Cr20 3 content and Cr:Fe ratios ofthe LG6 and LG8a chromitite seams decreases eastwards from the Ruighoek section. The average Cr:Fe ratio for the western Bushveld Complex is between 1.5 and\2.0, nonetheless, a progressively lower Cr:Fe ratio is noted from the LG1 chromitite up through to the MG4 chromitite seam in the Ruighoek section. tn the LG2 - LG4 chromitite interval a deviation to higher.lratios is encountered. A progressive substitution of Cr by AT and Fe in the Cr-spinel crystal lattice characterizes the chromitite succession from the LG1 seam up through the chromitite succession to MG4. The petrogeneSiS of the chromitite seams of the CZ is attributed to magma mixing and fractional crystallization of a single magma type.
- Full Text:
- Date Issued: 2000
The response of the two interrelated river components, geomorphology and riparian vegetation, to interbasin water transfers in the Orange-Fish-Sundays River Interbasin Transfer Scheme
- Authors: du Plessis, A J E
- Date: 2000
- Subjects: Skoenmakers River (South Africa) , Riparian ecology -- South Africa -- Eastern Cape , Geomorphology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4850 , http://hdl.handle.net/10962/d1005526
- Description: The Skoenmakers River (located in the semi-arid Karoo region of the Eastern Cape) is being used as a transfer route for water transferred by the Orange-Fish-Sundays River Interbasin Transfer Scheme. The change in the hydrological regime of this once ephemeral stream to a much bigger perennial river led to dramatic changes to both the physical structure and riparian vegetation structure of the river system. These changes differ for each of the three river sections, the upper,middle and lower reaches. Qualitative, descriptive geomorphological data was gathered by means of field observations and this was then compared to the quantitative data collected by means of surveyed cross-sectional profiles at selected sites along the length of both the regulated Skoenmakers River and a nonregulated tributary of equivalent size, the Volkers River. Riparian vegetation data was gathered by means of plot sampling along belt transects at each site. A qualitative assessment of the vegetation conditions was also made at each site and then added to the quantitative data from the plot sampling. At each site the different morphological units were identified along the cross-section and changes in the vegetation and sediment composition were recorded. Aerial photographs were used as additional sources of data and observations made from these were compared to data gathered in the field. The pre-IBT channel in this river section was formed by low frequency flood flows but the hydrological regime has now been converted to base flows much higher than normal flood flows. Severe incision, erosion and degradation of both the channel bed and banks occurred. In the lower reaches, post-IBT base flows are lower than pre-IBT flood flows and, due to the increased catchment area, the impact of the IBT was better ‘absorbed’ by the river system. Aggradation and deposition increased for the regulated river in comparison to the non-regulated river due to more sediment introduced The IBT had the greatest impact in the upper reaches of the regulated river due to more sediment introduced at the top of the system.
- Full Text:
- Date Issued: 2000
- Authors: du Plessis, A J E
- Date: 2000
- Subjects: Skoenmakers River (South Africa) , Riparian ecology -- South Africa -- Eastern Cape , Geomorphology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4850 , http://hdl.handle.net/10962/d1005526
- Description: The Skoenmakers River (located in the semi-arid Karoo region of the Eastern Cape) is being used as a transfer route for water transferred by the Orange-Fish-Sundays River Interbasin Transfer Scheme. The change in the hydrological regime of this once ephemeral stream to a much bigger perennial river led to dramatic changes to both the physical structure and riparian vegetation structure of the river system. These changes differ for each of the three river sections, the upper,middle and lower reaches. Qualitative, descriptive geomorphological data was gathered by means of field observations and this was then compared to the quantitative data collected by means of surveyed cross-sectional profiles at selected sites along the length of both the regulated Skoenmakers River and a nonregulated tributary of equivalent size, the Volkers River. Riparian vegetation data was gathered by means of plot sampling along belt transects at each site. A qualitative assessment of the vegetation conditions was also made at each site and then added to the quantitative data from the plot sampling. At each site the different morphological units were identified along the cross-section and changes in the vegetation and sediment composition were recorded. Aerial photographs were used as additional sources of data and observations made from these were compared to data gathered in the field. The pre-IBT channel in this river section was formed by low frequency flood flows but the hydrological regime has now been converted to base flows much higher than normal flood flows. Severe incision, erosion and degradation of both the channel bed and banks occurred. In the lower reaches, post-IBT base flows are lower than pre-IBT flood flows and, due to the increased catchment area, the impact of the IBT was better ‘absorbed’ by the river system. Aggradation and deposition increased for the regulated river in comparison to the non-regulated river due to more sediment introduced The IBT had the greatest impact in the upper reaches of the regulated river due to more sediment introduced at the top of the system.
- Full Text:
- Date Issued: 2000
Social workers perceptions on unionisation and collective bargaining : an exploratory study of the central region of the Eastern Cape
- Authors: Dyakala, Tumeka
- Date: 2000
- Subjects: Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:695 , http://hdl.handle.net/10962/d1006405 , Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
- Description: This study explores primarily the views of social workers in the Central region of the Eastern Cape on unionisation and collective bargaining, and at a secondary level the views of their employers and of the trade unions organising social workers, regarding social workers' involvement and non-involvement in these processes. It examines the paradox of compatibility of professionalism and unionism. There are two schools of thought regarding compatibility of professionalism and unionisation one views these concepts as antagonistic whilst the other views these concepts as complementary. Some social workers have been reluctant to participate in trade unions in the past until recently. Reasons advanced for their recent accelerated involvement in trade unions are explored in this study. Social workers views on the Labour Relations Act 66 of 1995 as the source of the legal framework, within which trade unions and employers interact, through the process of collective bargaining are explored. Proposed alternative mechanisms to these processes as perceived by social workers are closely examined. Semi-structured, self administered questionnaires were distributed to social workers whilst semi-structured interviews were conducted with employer representatives and trade union officials. This helped the researcher to have a broader view of the situation. Findings point to a scenario of disunity of both employers and employees in the social work profession. The study is a pioneering effort in the Central region and sets a way forward for further exploration of this subject. It is hoped that this study will make a worthwhile contribution to the social work profession's industrial relations field
- Full Text:
- Date Issued: 2000
- Authors: Dyakala, Tumeka
- Date: 2000
- Subjects: Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:695 , http://hdl.handle.net/10962/d1006405 , Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
- Description: This study explores primarily the views of social workers in the Central region of the Eastern Cape on unionisation and collective bargaining, and at a secondary level the views of their employers and of the trade unions organising social workers, regarding social workers' involvement and non-involvement in these processes. It examines the paradox of compatibility of professionalism and unionism. There are two schools of thought regarding compatibility of professionalism and unionisation one views these concepts as antagonistic whilst the other views these concepts as complementary. Some social workers have been reluctant to participate in trade unions in the past until recently. Reasons advanced for their recent accelerated involvement in trade unions are explored in this study. Social workers views on the Labour Relations Act 66 of 1995 as the source of the legal framework, within which trade unions and employers interact, through the process of collective bargaining are explored. Proposed alternative mechanisms to these processes as perceived by social workers are closely examined. Semi-structured, self administered questionnaires were distributed to social workers whilst semi-structured interviews were conducted with employer representatives and trade union officials. This helped the researcher to have a broader view of the situation. Findings point to a scenario of disunity of both employers and employees in the social work profession. The study is a pioneering effort in the Central region and sets a way forward for further exploration of this subject. It is hoped that this study will make a worthwhile contribution to the social work profession's industrial relations field
- Full Text:
- Date Issued: 2000
The use of indigenous macroinvertebrates and Daphnia pulex in acute toxicity testing
- Authors: Everitt, Victoria Jane
- Date: 2000
- Subjects: Water -- Pollution -- Toxicology , Toxicity testing , Daphnia pulex
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5795 , http://hdl.handle.net/10962/d1005483
- Description: Aquatic toxicology has been identified as a valuable tool in the identification and management of chemical pollution in aquatic ecosystems. Standardised methodologies for acute aquatic bioassays have been adopted from international agencies. As a result of these standard methods, the use of laboratory cultured organisms for toxicity testing has been more popular than that of indigenous field-caught organisms. Included in these adopted methods are those for the cultured crustacean Daphnia pUlex. D.pulex is adapted to living in standing water and the suitability of this species to determine toxic effects for South African riverine environments, which are largely flowing, has been questioned. Thus this thesis is a case-study ofthe use of D.pulex and indigenous site-specific macroinvertebrates as toxicity test organisms for setting acute water quality guidelines to protect aquatic ecosystems. The study highlights site-specific problems such as reference sites and organism identification. The acute tolerance of selected indigenous invertebrates was compared to that of D. pulex, using both a single-substance reference toxicant (zinc) and selected whole efiluents. The significance of source population and culture age as a potential source of biological variability between D.pulex cultures was also investigated. D.pulex cultures have been initiated in South Africa from females collected from a number of different local populations; also it is assumed that no genetic change (due to mutation) occurs within a D.pulex culture over time. In order to establish if source population and culture age are a source of biological variability between D.pulex experiments, the acute tolerJuce to zinc of two different D.pulex populations and three different generations within a population were compared. Due to experimental variability results were inconclusive, and differences in tolerance as a result of population difference or culture age could not be determined with confidence. The acute tolerance of D.pulex to a single reference chemical (zinc) and selected whole efiluents was compared to that of selected indigenous invertebrates. Acute 48 h D.pulex zinc tolerance (LC50 range: 0.22 - 0.60 mg/l Zn) was found to be more sensitive than acute 96 h tolerances shown by mayfly species A.fconurus peringueyi (Heptageniidae) (LC50: 17.42 mg/l Zn), Euthrauluselegans (Leptophlebiidae) (LC50: 0.98 mg/IZn), Ba~tidae (LC50: 0.94mg/IZn) and shrimp, Caradina nilotica (Atyidae) (LC50: 3.17 mg/l Zn). This result suggests that guidelines for zinc set using D.pulex will protect the selected indigenous invertebrates. Selected whole eftluents were not acutely toxic to either D.pulex or selected indigenous invertebrates. These experiments were used as a case study for method development regarding the comparative use of D.pulex and indigenous invertebrates in acute whole eftluent toxicity testing. Finally, it is recommended that a suite of indigenous organisms (e.g. macroinvertebrates, fish and algae), as well as laboratory cultured D.pulex, be used in the initial setting of guidelines and that D.pulex be used for routine compliance monitoring. It is futher recommended that a suite of available monitoring methods, such as chemical and biomonitoring methodologies, be used in conjuction with toxicity testing in water quality management.
- Full Text:
- Date Issued: 2000
- Authors: Everitt, Victoria Jane
- Date: 2000
- Subjects: Water -- Pollution -- Toxicology , Toxicity testing , Daphnia pulex
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5795 , http://hdl.handle.net/10962/d1005483
- Description: Aquatic toxicology has been identified as a valuable tool in the identification and management of chemical pollution in aquatic ecosystems. Standardised methodologies for acute aquatic bioassays have been adopted from international agencies. As a result of these standard methods, the use of laboratory cultured organisms for toxicity testing has been more popular than that of indigenous field-caught organisms. Included in these adopted methods are those for the cultured crustacean Daphnia pUlex. D.pulex is adapted to living in standing water and the suitability of this species to determine toxic effects for South African riverine environments, which are largely flowing, has been questioned. Thus this thesis is a case-study ofthe use of D.pulex and indigenous site-specific macroinvertebrates as toxicity test organisms for setting acute water quality guidelines to protect aquatic ecosystems. The study highlights site-specific problems such as reference sites and organism identification. The acute tolerance of selected indigenous invertebrates was compared to that of D. pulex, using both a single-substance reference toxicant (zinc) and selected whole efiluents. The significance of source population and culture age as a potential source of biological variability between D.pulex cultures was also investigated. D.pulex cultures have been initiated in South Africa from females collected from a number of different local populations; also it is assumed that no genetic change (due to mutation) occurs within a D.pulex culture over time. In order to establish if source population and culture age are a source of biological variability between D.pulex experiments, the acute tolerJuce to zinc of two different D.pulex populations and three different generations within a population were compared. Due to experimental variability results were inconclusive, and differences in tolerance as a result of population difference or culture age could not be determined with confidence. The acute tolerance of D.pulex to a single reference chemical (zinc) and selected whole efiluents was compared to that of selected indigenous invertebrates. Acute 48 h D.pulex zinc tolerance (LC50 range: 0.22 - 0.60 mg/l Zn) was found to be more sensitive than acute 96 h tolerances shown by mayfly species A.fconurus peringueyi (Heptageniidae) (LC50: 17.42 mg/l Zn), Euthrauluselegans (Leptophlebiidae) (LC50: 0.98 mg/IZn), Ba~tidae (LC50: 0.94mg/IZn) and shrimp, Caradina nilotica (Atyidae) (LC50: 3.17 mg/l Zn). This result suggests that guidelines for zinc set using D.pulex will protect the selected indigenous invertebrates. Selected whole eftluents were not acutely toxic to either D.pulex or selected indigenous invertebrates. These experiments were used as a case study for method development regarding the comparative use of D.pulex and indigenous invertebrates in acute whole eftluent toxicity testing. Finally, it is recommended that a suite of indigenous organisms (e.g. macroinvertebrates, fish and algae), as well as laboratory cultured D.pulex, be used in the initial setting of guidelines and that D.pulex be used for routine compliance monitoring. It is futher recommended that a suite of available monitoring methods, such as chemical and biomonitoring methodologies, be used in conjuction with toxicity testing in water quality management.
- Full Text:
- Date Issued: 2000
The scrum-down on brain damage effects of cumulative mild head injury in rugby: a comparison of group mean scores between national rugby players and non-contact sport controls
- Authors: Finkelstein, Melissa
- Date: 2000
- Subjects: Sports injuries , Head -- Wounds and injuries , Sports injuries -- Psychological aspects , Neuropsychological tests , Rugby football injuries
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:2976 , http://hdl.handle.net/10962/d1002485 , Sports injuries , Head -- Wounds and injuries , Sports injuries -- Psychological aspects , Neuropsychological tests , Rugby football injuries
- Description: The present study comprises the second phase of a larger and ongoing research study investigating the brain damage effects of cumulative mild head injury in rugby. The purpose of this study was to determine whether cumulative mild head injury sustained in the game of rugby would cause brain injury as evidenced by impaired performance on sensitive neuropsychological tests. Participants were Springbok professional rugby players (n = 26), Under 21 rugby players (n = 19), and a non-contact sport control of national hockey players (n = 21). Comparisons of performance were carried out across a spectrum of neuropsychological tests for the three rugby groups (Total Rugby, Springbok Rugby, and Under 21 Rugby) versus the performance of the non-contact sport control group (Hockey Control), as well as comparisons of performance f9r the subgroups of Rugby Forwards versus Rugby Backs. Comparisons revealed a consistent pattern of poorer performance across all rugby groups relative to the performance of the controls on tests highly sensitive to the effects of diffuse brain damage. Within rugby group comparisons (Forwards versus Backs) showed significantly poorer performance for Total Rugby Forwards and Springbok Rugby Forwards relative to the performance of the respective Total Rugby Backs and Springbok Rugby Backs on sensitive, as well as on somewhat less sensitive, neuropsychological tests. The performance of Under 21 Rugby Forwards relative to Under 21 Rugby Backs demonstrated similar trends. Brain reserve capacity theory was used as a conceptual basis for discussing the implications of these findings.
- Full Text:
- Date Issued: 2000
- Authors: Finkelstein, Melissa
- Date: 2000
- Subjects: Sports injuries , Head -- Wounds and injuries , Sports injuries -- Psychological aspects , Neuropsychological tests , Rugby football injuries
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:2976 , http://hdl.handle.net/10962/d1002485 , Sports injuries , Head -- Wounds and injuries , Sports injuries -- Psychological aspects , Neuropsychological tests , Rugby football injuries
- Description: The present study comprises the second phase of a larger and ongoing research study investigating the brain damage effects of cumulative mild head injury in rugby. The purpose of this study was to determine whether cumulative mild head injury sustained in the game of rugby would cause brain injury as evidenced by impaired performance on sensitive neuropsychological tests. Participants were Springbok professional rugby players (n = 26), Under 21 rugby players (n = 19), and a non-contact sport control of national hockey players (n = 21). Comparisons of performance were carried out across a spectrum of neuropsychological tests for the three rugby groups (Total Rugby, Springbok Rugby, and Under 21 Rugby) versus the performance of the non-contact sport control group (Hockey Control), as well as comparisons of performance f9r the subgroups of Rugby Forwards versus Rugby Backs. Comparisons revealed a consistent pattern of poorer performance across all rugby groups relative to the performance of the controls on tests highly sensitive to the effects of diffuse brain damage. Within rugby group comparisons (Forwards versus Backs) showed significantly poorer performance for Total Rugby Forwards and Springbok Rugby Forwards relative to the performance of the respective Total Rugby Backs and Springbok Rugby Backs on sensitive, as well as on somewhat less sensitive, neuropsychological tests. The performance of Under 21 Rugby Forwards relative to Under 21 Rugby Backs demonstrated similar trends. Brain reserve capacity theory was used as a conceptual basis for discussing the implications of these findings.
- Full Text:
- Date Issued: 2000
Criteria social workers employ in making child custody recommendations
- Authors: Froneman, Anna Petronella
- Date: 2000
- Subjects: Custody of children -- South Africa Social work with children -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:696 , http://hdl.handle.net/10962/d1006414
- Description: During this study, an attempt was made to investigate the process employed by social workers in conducting child custody evaluations and making decisions related to the process, as well as to provide insight into which criteria are currently being used. The goal was to explore the perceived usefulness of these criteria from the perspective of social work, and to assess the adequacy of the requirements of the custody report in reflecting the above process and decision-making. In order to meet this goal, literature and empirical studies were conducted. The literature study focuses on the history of child custody matters, custody decision-making and legislation, types of custody arrangements, criteria social workers employ in making child custody recommendations, evaluator bias and custody evaluation reports. During the empirical research phase, a non-probability purposive sampling procedure was adopted. Five family counsellors from the office of the family advocate serving the Eastern Cape were selected. After an interview schedule was compiled to cover certain topics and their sequence, semi-structured interviews were conducted with the family counsellors. In order to compare the criteria stated in the interviews with the criteria applied in the custody reports, three cases from each family counsellor were selected and the final custody report and recommendation were studied. This study has revealed the following: some of the family counsellors experience proqlems with the process of custody evaluations; certain aspects regarding the process are not in line with some ofthe literature; some of the criteria used by the family counsellors are not evident in the custody reports and are not discussed in detail; a lack of training exists for the family counsellors; and the family counsellors experience some form of bias. Finally, based on the research findings, recommendations were made regarding the process of custody evaluation, the criteria social workers employ when conducting child custody evaluations, training and bias of family counsellors, the role of the family advocate and possible future research.
- Full Text:
- Date Issued: 2000
- Authors: Froneman, Anna Petronella
- Date: 2000
- Subjects: Custody of children -- South Africa Social work with children -- South Africa
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:696 , http://hdl.handle.net/10962/d1006414
- Description: During this study, an attempt was made to investigate the process employed by social workers in conducting child custody evaluations and making decisions related to the process, as well as to provide insight into which criteria are currently being used. The goal was to explore the perceived usefulness of these criteria from the perspective of social work, and to assess the adequacy of the requirements of the custody report in reflecting the above process and decision-making. In order to meet this goal, literature and empirical studies were conducted. The literature study focuses on the history of child custody matters, custody decision-making and legislation, types of custody arrangements, criteria social workers employ in making child custody recommendations, evaluator bias and custody evaluation reports. During the empirical research phase, a non-probability purposive sampling procedure was adopted. Five family counsellors from the office of the family advocate serving the Eastern Cape were selected. After an interview schedule was compiled to cover certain topics and their sequence, semi-structured interviews were conducted with the family counsellors. In order to compare the criteria stated in the interviews with the criteria applied in the custody reports, three cases from each family counsellor were selected and the final custody report and recommendation were studied. This study has revealed the following: some of the family counsellors experience proqlems with the process of custody evaluations; certain aspects regarding the process are not in line with some ofthe literature; some of the criteria used by the family counsellors are not evident in the custody reports and are not discussed in detail; a lack of training exists for the family counsellors; and the family counsellors experience some form of bias. Finally, based on the research findings, recommendations were made regarding the process of custody evaluation, the criteria social workers employ when conducting child custody evaluations, training and bias of family counsellors, the role of the family advocate and possible future research.
- Full Text:
- Date Issued: 2000
The structure and microbiology of floating sulphide oxidising biofilms
- Authors: Gilfillan, Joanne Criseyde
- Date: 2000
- Subjects: Biofilms , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3903 , http://hdl.handle.net/10962/d1003962 , Biofilms , Sulfides
- Description: Floating sulphur biofilms are observed as surface layers in numerous aquatic sulphide-rich environments, and apparently play an important role in the cycling of sulphur in its various oxidation states. In addition to the conversion of sulphide to sulphur and/or sulphate species, it has been suspected that subsequent reduction back to sulphide may occur within the floating sulphur biofi1m in organic-rich environments. The use of sulphur biofilms for the harvesting of elemental sulphur from wastewater treatment systems has also been suggested. There is, however, little documented information in the literature on the structure of floating sulphur biofilms, or the microbial species responsible for their occurrence. In this study, floating sulphur biofilms were generated in a continuous flow baflle reactor and their structure was examined using scanning electron microscopy. It was found that they occur as layered structures with morphologically distinct bacterial forms present in different layers of the biofilm. The biofilpl structure was also found to be dynamic, with structural changes observed as feed conditions were altered. An enriched culture derived from the biofi1m demonstrated rates of sulphide oxidation comparable to values reported in the literature for liquid culture systems. The microbiology of the biofi1m was studied using traditional plate culture techniques and analysis ofrRNA genes. Identification of plate culture isolates as representatives of the biofi1m community proved to be limited, leading to a PeR-based cloning approach. The majority of the organisms present in the sulphur biofi1m were classified as species in the genus ~eudomonas, and a number of other bacterial species whose sulphide oxidising capacity has been noted previously. Surprisingly, only 2% of the clone library consisted of Thiobacillus spp., and no sulphate reducing bacteria were identified in the biofilm at all. These results indicate that in organic sulphide-rich environments facultative chemolithoheterotrophic bacterial forms predominate in floating sulphur biofilms, and that the complete biological cycling of sulphur may not occur in these systems.
- Full Text:
- Date Issued: 2000
- Authors: Gilfillan, Joanne Criseyde
- Date: 2000
- Subjects: Biofilms , Sulfides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3903 , http://hdl.handle.net/10962/d1003962 , Biofilms , Sulfides
- Description: Floating sulphur biofilms are observed as surface layers in numerous aquatic sulphide-rich environments, and apparently play an important role in the cycling of sulphur in its various oxidation states. In addition to the conversion of sulphide to sulphur and/or sulphate species, it has been suspected that subsequent reduction back to sulphide may occur within the floating sulphur biofi1m in organic-rich environments. The use of sulphur biofilms for the harvesting of elemental sulphur from wastewater treatment systems has also been suggested. There is, however, little documented information in the literature on the structure of floating sulphur biofilms, or the microbial species responsible for their occurrence. In this study, floating sulphur biofilms were generated in a continuous flow baflle reactor and their structure was examined using scanning electron microscopy. It was found that they occur as layered structures with morphologically distinct bacterial forms present in different layers of the biofilm. The biofilpl structure was also found to be dynamic, with structural changes observed as feed conditions were altered. An enriched culture derived from the biofi1m demonstrated rates of sulphide oxidation comparable to values reported in the literature for liquid culture systems. The microbiology of the biofi1m was studied using traditional plate culture techniques and analysis ofrRNA genes. Identification of plate culture isolates as representatives of the biofi1m community proved to be limited, leading to a PeR-based cloning approach. The majority of the organisms present in the sulphur biofi1m were classified as species in the genus ~eudomonas, and a number of other bacterial species whose sulphide oxidising capacity has been noted previously. Surprisingly, only 2% of the clone library consisted of Thiobacillus spp., and no sulphate reducing bacteria were identified in the biofilm at all. These results indicate that in organic sulphide-rich environments facultative chemolithoheterotrophic bacterial forms predominate in floating sulphur biofilms, and that the complete biological cycling of sulphur may not occur in these systems.
- Full Text:
- Date Issued: 2000
Nyau masquerade performance : shifting the imperial gaze
- Authors: Guhrs, Tamara
- Date: 2000
- Subjects: Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2140 , http://hdl.handle.net/10962/d1002372 , Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Description: Nyau Masquerades have been studied by missionaries, anthropologists and religious specialists, but have seldom been documented by theatre and performance specialists. This dissertation argues for the acceptance of Ny au performance as a contemporary world theatre form rooted in tradition. Charting the uneasy relationship between the Nyau and those who have sought to record their performances, the author delineates a vivid dramaturgy of this art form. In doing so, the boundaries of what define theatre as it has traditionally been understood in dominant discourses are made more fluid. Nyau performances have been affected by Colonial processes in varied ways. They were banned by the former government of Northern Rhodesia and severely censored by Catholic Mission teachings in the former Nyasaland. Other forms of vilification have been more subtle. Information about performance in Africa has often been collected and arranged in ways which limit the understanding of these genres. Images of Africa which cluster around the notion of the 'Primitive Other' have enabled a representation of Ny au masking as a superstitious and outdated practice with no relevance for contemporary Africa. This work calls for a new examination of the Nyau, through the lens of local discourse as well as contemporary global understandings of performance. Chapter One examines the issue of primitivism and the ways in which Africa has historically been posited as the exotic Other to Europe. Chapter Two examines the Nyau ih terms of specific dramaturgical elements, adjusting previous misconceptions surrounding the theatr~ forms of Chewa and Nyanja people. Chapter Three is devoted to a discussion of space in ritual theatre and Nyau performance, while Chapter Four explores masking and questions of transformation and liminality. In conclusion, it is seen that the use of the mask is a metaphor for the suspension of rigid boundaries separating subject/object, self/other, ritual/theatre, a suspension which needs to take place before an enriched understanding of performance in Africa can be reached.
- Full Text:
- Date Issued: 2000
- Authors: Guhrs, Tamara
- Date: 2000
- Subjects: Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2140 , http://hdl.handle.net/10962/d1002372 , Masquerades -- Malawi , Masquerades -- Zambia , Malawi -- Religion , Zambia -- Religion , Masks, Chewa , Chewa (African people) -- Rites and ceremonies , Nyanja (African people) -- Rites and ceremonies , Secret societies -- Africa
- Description: Nyau Masquerades have been studied by missionaries, anthropologists and religious specialists, but have seldom been documented by theatre and performance specialists. This dissertation argues for the acceptance of Ny au performance as a contemporary world theatre form rooted in tradition. Charting the uneasy relationship between the Nyau and those who have sought to record their performances, the author delineates a vivid dramaturgy of this art form. In doing so, the boundaries of what define theatre as it has traditionally been understood in dominant discourses are made more fluid. Nyau performances have been affected by Colonial processes in varied ways. They were banned by the former government of Northern Rhodesia and severely censored by Catholic Mission teachings in the former Nyasaland. Other forms of vilification have been more subtle. Information about performance in Africa has often been collected and arranged in ways which limit the understanding of these genres. Images of Africa which cluster around the notion of the 'Primitive Other' have enabled a representation of Ny au masking as a superstitious and outdated practice with no relevance for contemporary Africa. This work calls for a new examination of the Nyau, through the lens of local discourse as well as contemporary global understandings of performance. Chapter One examines the issue of primitivism and the ways in which Africa has historically been posited as the exotic Other to Europe. Chapter Two examines the Nyau ih terms of specific dramaturgical elements, adjusting previous misconceptions surrounding the theatr~ forms of Chewa and Nyanja people. Chapter Three is devoted to a discussion of space in ritual theatre and Nyau performance, while Chapter Four explores masking and questions of transformation and liminality. In conclusion, it is seen that the use of the mask is a metaphor for the suspension of rigid boundaries separating subject/object, self/other, ritual/theatre, a suspension which needs to take place before an enriched understanding of performance in Africa can be reached.
- Full Text:
- Date Issued: 2000
Feeding biology of three euphausiid species in the vicinity of the Prince Edward Archipelago (Southern Ocean)
- Authors: Gurney, Leigh Josephine
- Date: 2000
- Subjects: Euphausiacea , Euphausiacea -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5695 , http://hdl.handle.net/10962/d1005381 , Euphausiacea , Euphausiacea -- Feeding and feeds
- Description: The feeding biology of three euphausiid species, Euphausia vallentini (adults and juveniles), E. longirostris and Nematoscelis megalops was investigated during austral autumn (April/May) of 1998 and 1999, in the vicinity of the Prince Edward Islands (Southern Ocean). Data on the abundance and biomass of these species, estimated from bongo net tows, were investigated. Trophic position was assessed using gut contents and stable nitrogen isotope measurements. Feeding rate and daily carbon ration were estimated using the gut fluorescence and the gut fullness techniques. Vertical migrations into the surface waters at night were found to be strong for Euphausia vallentini adults and juveniles. Associated with these migrations were clear diel feeding patterns. Insufficient data during daylight hours for E. longirostris made it impossible to determine diel feeding patterns, but high feeding activity did occur during dark hours. Nematoscelis megalops did not show any distinct diel feeding pattern, but slightly higher gut fullness indices in the late afternoon suggested that feeding activity may have been highest during this period. For both Euphausia spp. high gut pigment levels were recorded in 1999, which corresponded to higher ambient chlorophyll a concentrations for that year. Highest initial gut pigment levels and highest ingestion rates were found for Euphausia longirostris in both years and lowest values were observed for N. megalops. High phytoplankton and low metazoan contributions to the diet of Euphausia vallentini juveniles, as shown in the gut content analysis, and low stable nitrogen isotope ratios (ð¹⁵N = 1.39±0.31), both indicated that this group was principally herbivorous. The results of gut content analysis of the adults of E. vallentini were similar to those of the juveniles, however, stable nitrogen isotope results showed that there was a higher degree of omnivory (ð¹⁵N = 3.81±0.66). Daily ration estimates from the gut fluorescence and fullness techniques showed that between 3.3 and 25.7 % of E. vallentini adults total daily carbon ration was derived from autotrophic sources. Although the contribution of carnivory to the diet was difficult to determine, the adults of this species may be considered omnivorous. Irrespective of the degree of carnivory, a dietry shift with an increase in size was evident for this species. Gut content analysis for Euphausia longirostris showed that this species consumed large amounts of both phytoplankton and metazoan prey and this was reflected in the stable nitrogen isotope results (ð¹⁵N = 6.88±0.60). These findings were supported by the results of the daily carbon ration estimates which showed that autotrophic carbon contributed between 6.9 and 20.3 % of the daily carbon consumption. The gut content analysis suggested that N. megalops was omnivorous, and the stable nitrogen isotope results place it in a trophic position equivalent to that of E. longirostris (ð¹⁵N = 6.83±0.78). Calculations from daily ration estimates suggested that only 3.1 % in 1998, and 3.2 % in 1999, of the carbon ingested was of autotrophic origin. This species may therefore be considered carnivorous. Implications of the findings of this study are discussed in terms of carbon cycling in the Southern Ocean.
- Full Text:
- Date Issued: 2000
- Authors: Gurney, Leigh Josephine
- Date: 2000
- Subjects: Euphausiacea , Euphausiacea -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5695 , http://hdl.handle.net/10962/d1005381 , Euphausiacea , Euphausiacea -- Feeding and feeds
- Description: The feeding biology of three euphausiid species, Euphausia vallentini (adults and juveniles), E. longirostris and Nematoscelis megalops was investigated during austral autumn (April/May) of 1998 and 1999, in the vicinity of the Prince Edward Islands (Southern Ocean). Data on the abundance and biomass of these species, estimated from bongo net tows, were investigated. Trophic position was assessed using gut contents and stable nitrogen isotope measurements. Feeding rate and daily carbon ration were estimated using the gut fluorescence and the gut fullness techniques. Vertical migrations into the surface waters at night were found to be strong for Euphausia vallentini adults and juveniles. Associated with these migrations were clear diel feeding patterns. Insufficient data during daylight hours for E. longirostris made it impossible to determine diel feeding patterns, but high feeding activity did occur during dark hours. Nematoscelis megalops did not show any distinct diel feeding pattern, but slightly higher gut fullness indices in the late afternoon suggested that feeding activity may have been highest during this period. For both Euphausia spp. high gut pigment levels were recorded in 1999, which corresponded to higher ambient chlorophyll a concentrations for that year. Highest initial gut pigment levels and highest ingestion rates were found for Euphausia longirostris in both years and lowest values were observed for N. megalops. High phytoplankton and low metazoan contributions to the diet of Euphausia vallentini juveniles, as shown in the gut content analysis, and low stable nitrogen isotope ratios (ð¹⁵N = 1.39±0.31), both indicated that this group was principally herbivorous. The results of gut content analysis of the adults of E. vallentini were similar to those of the juveniles, however, stable nitrogen isotope results showed that there was a higher degree of omnivory (ð¹⁵N = 3.81±0.66). Daily ration estimates from the gut fluorescence and fullness techniques showed that between 3.3 and 25.7 % of E. vallentini adults total daily carbon ration was derived from autotrophic sources. Although the contribution of carnivory to the diet was difficult to determine, the adults of this species may be considered omnivorous. Irrespective of the degree of carnivory, a dietry shift with an increase in size was evident for this species. Gut content analysis for Euphausia longirostris showed that this species consumed large amounts of both phytoplankton and metazoan prey and this was reflected in the stable nitrogen isotope results (ð¹⁵N = 6.88±0.60). These findings were supported by the results of the daily carbon ration estimates which showed that autotrophic carbon contributed between 6.9 and 20.3 % of the daily carbon consumption. The gut content analysis suggested that N. megalops was omnivorous, and the stable nitrogen isotope results place it in a trophic position equivalent to that of E. longirostris (ð¹⁵N = 6.83±0.78). Calculations from daily ration estimates suggested that only 3.1 % in 1998, and 3.2 % in 1999, of the carbon ingested was of autotrophic origin. This species may therefore be considered carnivorous. Implications of the findings of this study are discussed in terms of carbon cycling in the Southern Ocean.
- Full Text:
- Date Issued: 2000
The presence and role of arbuscular mycorrhizal fungi in coastal sand dune systems
- Authors: Haller, Anjanette H. A
- Date: 2000
- Subjects: Mycorrhizas , Sand dune ecology -- South Africa , Mycorrhizal fungi
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4196 , http://hdl.handle.net/10962/d1003765 , Mycorrhizas , Sand dune ecology -- South Africa , Mycorrhizal fungi
- Description: Arbuscular mycorrhizas (AM) are mutually beneficial symbiotic associations between the roots of plants and certain Zygomycetous fungi. The role of AM fungi in coastal sand dunes has been explored in many parts of the world, though little work has been conducted in South African dune systems. This study aimed to investigate the presence and extent of mycorrhizal colonisation of a coastal sand dune in South Africa. The roots of five plant species (Scaevola plumieri, Arctotheca populifolia, Ipomoea pes-caprae, Ehrharta villosa and Chrysanthemoides monilifera) were sampled along a foredune profile at Old Woman's River in the Eastern Cape. These roots were assessed for the percentage mycorrhizal colonisation they supported. Spores extracted from the rhizosphere sand of each plant species were counted and identified to genus level. Results were related to seasonality and the position of the plants along the profile. All plant species were found to be mycorrhizal. Percentage colonisation ranged from 0-92%, depending on plant species and season. Mycorrhizal colonisation was generally highest in the winter months, and especially so in I pes-caprae and E. villosa. The extent of various mycorrhizal structures in root tissue varied between plant species. Spore numbers ranged from 0-48 spores 100g-1 sand with highest numbers occurring in winter. S. plumieri and A. populifolia were associated with greatest spore abundance. Four fungal genera (Glomus, Acaulospora, Scutellospora and Gigaspora) were identified. Distribution of these genera showed seasonal variations between plant species. A bioassay, using Sorghum, was conducted to test the inoculum potentials of sand from the Scaevola hummock and the IpomoealEhrharta dune. Highest percentage colonisation occurred in plants grown in the Scaevola sand, which also had the lowest root and shoot measurements. The bioassay confirmed that AM propagules are present and viable, even in the mobile sand of the foredune. This study showed that mycorrhizal colonisation and spore numbers varied seasonally, but that the extent of this was dependent on plant species. The position of plants along the foredune profile tended to be less important than plant species. It is thought that the growth cycle and rooting system of each plant species determines seasonal cycles and abundance of AM fungi. Variation within fungal populations probably also impacts on this. Knowledge of the presence and distribution of AM fungi in this system paves the way for more detailed studies which need to examine the role of these endophytes in South African sand dunes.
- Full Text:
- Date Issued: 2000
- Authors: Haller, Anjanette H. A
- Date: 2000
- Subjects: Mycorrhizas , Sand dune ecology -- South Africa , Mycorrhizal fungi
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4196 , http://hdl.handle.net/10962/d1003765 , Mycorrhizas , Sand dune ecology -- South Africa , Mycorrhizal fungi
- Description: Arbuscular mycorrhizas (AM) are mutually beneficial symbiotic associations between the roots of plants and certain Zygomycetous fungi. The role of AM fungi in coastal sand dunes has been explored in many parts of the world, though little work has been conducted in South African dune systems. This study aimed to investigate the presence and extent of mycorrhizal colonisation of a coastal sand dune in South Africa. The roots of five plant species (Scaevola plumieri, Arctotheca populifolia, Ipomoea pes-caprae, Ehrharta villosa and Chrysanthemoides monilifera) were sampled along a foredune profile at Old Woman's River in the Eastern Cape. These roots were assessed for the percentage mycorrhizal colonisation they supported. Spores extracted from the rhizosphere sand of each plant species were counted and identified to genus level. Results were related to seasonality and the position of the plants along the profile. All plant species were found to be mycorrhizal. Percentage colonisation ranged from 0-92%, depending on plant species and season. Mycorrhizal colonisation was generally highest in the winter months, and especially so in I pes-caprae and E. villosa. The extent of various mycorrhizal structures in root tissue varied between plant species. Spore numbers ranged from 0-48 spores 100g-1 sand with highest numbers occurring in winter. S. plumieri and A. populifolia were associated with greatest spore abundance. Four fungal genera (Glomus, Acaulospora, Scutellospora and Gigaspora) were identified. Distribution of these genera showed seasonal variations between plant species. A bioassay, using Sorghum, was conducted to test the inoculum potentials of sand from the Scaevola hummock and the IpomoealEhrharta dune. Highest percentage colonisation occurred in plants grown in the Scaevola sand, which also had the lowest root and shoot measurements. The bioassay confirmed that AM propagules are present and viable, even in the mobile sand of the foredune. This study showed that mycorrhizal colonisation and spore numbers varied seasonally, but that the extent of this was dependent on plant species. The position of plants along the foredune profile tended to be less important than plant species. It is thought that the growth cycle and rooting system of each plant species determines seasonal cycles and abundance of AM fungi. Variation within fungal populations probably also impacts on this. Knowledge of the presence and distribution of AM fungi in this system paves the way for more detailed studies which need to examine the role of these endophytes in South African sand dunes.
- Full Text:
- Date Issued: 2000
"Changing ourselves, changing others" : an analysis of the life stories of participants in a training course for volunteers within a non-governmental organisation in the Eastern Cape Province of South Africa
- Authors: Harper, Christopher Duncan
- Date: 2000
- Subjects: Non-governmental organizations -- South Africa -- Eastern Cape , Violence -- South Africa -- Eastern Cape , Abused women -- Counseling of , Women -- Crimes against -- South Africa , Volunteers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2985 , http://hdl.handle.net/10962/d1002494 , Non-governmental organizations -- South Africa -- Eastern Cape , Violence -- South Africa -- Eastern Cape , Abused women -- Counseling of , Women -- Crimes against -- South Africa , Volunteers
- Description: Gender-based violence has been recognized as a pressing mental health problem that is prevalent within South African society. Non-governmental organizations play a major role in addressing and highlighting the issue. These organizations make use of volunteers in order to assist in meeting their goals. The modernist perspective has been the dominant investigative mode when research into volunteers has been conducted. However, this study has been conducted with an emphasis on narrative. In its use of this constitutionalist and deconstructive perspective, it examines the identity of the research participants within the dominant social and cultural discourses that story their lives. This presents a major challenge to the modernist framework. In examining the life stories of the participants an emergent nature of identity is noted. Through the process of storying their lives and ascribing meaning to their experiences and understandings, the participants engaged in a process of constructing their identity. This research recognizes that identity is both multi-sited and multi-storied. The emphasis on personal agency enables the participants to restory their lives in the light of challenging prevailing discourses. It is in this process of challenge that they reauthor their lives and are in a position to change their own lives and the lives of others.
- Full Text:
- Date Issued: 2000
- Authors: Harper, Christopher Duncan
- Date: 2000
- Subjects: Non-governmental organizations -- South Africa -- Eastern Cape , Violence -- South Africa -- Eastern Cape , Abused women -- Counseling of , Women -- Crimes against -- South Africa , Volunteers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2985 , http://hdl.handle.net/10962/d1002494 , Non-governmental organizations -- South Africa -- Eastern Cape , Violence -- South Africa -- Eastern Cape , Abused women -- Counseling of , Women -- Crimes against -- South Africa , Volunteers
- Description: Gender-based violence has been recognized as a pressing mental health problem that is prevalent within South African society. Non-governmental organizations play a major role in addressing and highlighting the issue. These organizations make use of volunteers in order to assist in meeting their goals. The modernist perspective has been the dominant investigative mode when research into volunteers has been conducted. However, this study has been conducted with an emphasis on narrative. In its use of this constitutionalist and deconstructive perspective, it examines the identity of the research participants within the dominant social and cultural discourses that story their lives. This presents a major challenge to the modernist framework. In examining the life stories of the participants an emergent nature of identity is noted. Through the process of storying their lives and ascribing meaning to their experiences and understandings, the participants engaged in a process of constructing their identity. This research recognizes that identity is both multi-sited and multi-storied. The emphasis on personal agency enables the participants to restory their lives in the light of challenging prevailing discourses. It is in this process of challenge that they reauthor their lives and are in a position to change their own lives and the lives of others.
- Full Text:
- Date Issued: 2000