Help or hindrance? a critical analysis of the agreement on sanitary and phytosanitary measures, and its effects on developing countries
- Authors: Waterworth, Tayla
- Date: 2017
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10962/7090 , vital:21216
- Description: WHILE it is accepted that the category of "developing country" is a broad one, it can nevertheless be acknowledged that the countries which fall within this categorisation share several common features. Such common features include their lack of financial resources and scientific capacity, and their reliance on trade in primary agricultural goods. The Agreement on Sanitary and Phytosanitary Measures was originally created to regulate trade in primary agricultural goods, and so its provisions are of great significance to developing countries. In its Preamble the Agreement acknowledges both the unique circumstances of developing countries and its desire to assist them in entering into and expanding within the international trading markets. As part of this endeavour, several provisions were included in the Agreement which purport to protect and provide for the interests of developing countries. In its inception, its Preamble, and the very nature of its content, the Agreement shows a desire to assist developing countries wherever possible. Unfortunately, a close analysis of the provisions of the Agreement shows that this desire has not been fulfilled. Many of the provisions of the Agreement are heavily skewed toward the interests of importing Members, often at the expense of developing Members - particularly those that export primary agricultural goods. Even the provisions of the Agreement which purport to provide protection and special and differential treatment specifically for developing countries frequently fall short, either as a result of ambiguous phrasing or poor textual interpretation by the dispute settlement bodies of the World Trade Organization. As a result, there exists a potential within the Agreement to have a significant detrimental impact on the international trading opportunities of exporting developing countries. In this thesis I analyse the provisions of the Agreement to determine where, why and how they are likely to have, or are having, a detrimental impact on developing countries (particularly exporting developing countries). After identifying these problems I examine and discuss several potential solutions and how they may be implemented to minimise - or even remove - the negative impact on developing countries and their international trading markets.
- Full Text:
- Date Issued: 2017
- Authors: Waterworth, Tayla
- Date: 2017
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10962/7090 , vital:21216
- Description: WHILE it is accepted that the category of "developing country" is a broad one, it can nevertheless be acknowledged that the countries which fall within this categorisation share several common features. Such common features include their lack of financial resources and scientific capacity, and their reliance on trade in primary agricultural goods. The Agreement on Sanitary and Phytosanitary Measures was originally created to regulate trade in primary agricultural goods, and so its provisions are of great significance to developing countries. In its Preamble the Agreement acknowledges both the unique circumstances of developing countries and its desire to assist them in entering into and expanding within the international trading markets. As part of this endeavour, several provisions were included in the Agreement which purport to protect and provide for the interests of developing countries. In its inception, its Preamble, and the very nature of its content, the Agreement shows a desire to assist developing countries wherever possible. Unfortunately, a close analysis of the provisions of the Agreement shows that this desire has not been fulfilled. Many of the provisions of the Agreement are heavily skewed toward the interests of importing Members, often at the expense of developing Members - particularly those that export primary agricultural goods. Even the provisions of the Agreement which purport to provide protection and special and differential treatment specifically for developing countries frequently fall short, either as a result of ambiguous phrasing or poor textual interpretation by the dispute settlement bodies of the World Trade Organization. As a result, there exists a potential within the Agreement to have a significant detrimental impact on the international trading opportunities of exporting developing countries. In this thesis I analyse the provisions of the Agreement to determine where, why and how they are likely to have, or are having, a detrimental impact on developing countries (particularly exporting developing countries). After identifying these problems I examine and discuss several potential solutions and how they may be implemented to minimise - or even remove - the negative impact on developing countries and their international trading markets.
- Full Text:
- Date Issued: 2017
Homecoming
- Authors: Mazwai, Nontsikelelo
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164930 , vital:41185
- Description: Thesis (MA)--Rhodes University, Faculty of Humanities, School of Languages, 2017
- Full Text:
- Date Issued: 2017
- Authors: Mazwai, Nontsikelelo
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: thesis , text , Masters , MA
- Identifier: http://hdl.handle.net/10962/164930 , vital:41185
- Description: Thesis (MA)--Rhodes University, Faculty of Humanities, School of Languages, 2017
- Full Text:
- Date Issued: 2017
I did not die
- Authors: Mzamo, Tebello
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7246 , vital:21232
- Description: My novella is about a mine worker and his family. Set in both Lesotho and South Africa, it engages the effects of migrant labour on families in post-apartheid South Africa. Told through the eyes of the different family members, the narrative uses shifting points of view and moves fluidly through time to present an intimate but complex view of the lives of ordinary working class people. It incorporates witchcraft and ghosts to reveal the blurred lines between the realms of life and death. This collection is inspired by my own father who is a former mine worker. I am influenced by Joyce Carol Oates and Chibundu Onuzo's darkly realistic style, Veronique Tadjo’s explorations of migration and death, the family chronicles of Chimamanda Ngozi Adichie and Yvonne Adhiambo Owuor. I am also inspired by female fantasy and horror writers such as those collected in Ann and Jeff VanderMeer’s anthology, Sisters of the Revolution: A Feminist Speculative Fiction Anthology.
- Full Text:
- Date Issued: 2017
- Authors: Mzamo, Tebello
- Date: 2017
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7246 , vital:21232
- Description: My novella is about a mine worker and his family. Set in both Lesotho and South Africa, it engages the effects of migrant labour on families in post-apartheid South Africa. Told through the eyes of the different family members, the narrative uses shifting points of view and moves fluidly through time to present an intimate but complex view of the lives of ordinary working class people. It incorporates witchcraft and ghosts to reveal the blurred lines between the realms of life and death. This collection is inspired by my own father who is a former mine worker. I am influenced by Joyce Carol Oates and Chibundu Onuzo's darkly realistic style, Veronique Tadjo’s explorations of migration and death, the family chronicles of Chimamanda Ngozi Adichie and Yvonne Adhiambo Owuor. I am also inspired by female fantasy and horror writers such as those collected in Ann and Jeff VanderMeer’s anthology, Sisters of the Revolution: A Feminist Speculative Fiction Anthology.
- Full Text:
- Date Issued: 2017
I want to believe there is a girl here under the table
- Authors: Asfour, Fouad-Martin
- Date: 2017
- Subjects: Creative writing (Higher education) South Africa , South African fiction (English) 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7190 , vital:21227
- Description: Written in non-linear fragments, my thesis is what Audre Lorde in her novel Zami calls a "biomythography" - the weaving together of myth, history and biography in epic narrative form, a style of composition that represents all the ways in which we perceive the world. Using repetition and shifting memories, I draw from my bicultural upbringing in Offenbach, a city in Germany populated mostly by migrants, as well as my experience of working in art and culture internationally, travelling and living in different countries. Interrogating objects, buildings, family photographs, books and movies, and listening to the silences of the unvoiced, I upset and play with experiences of othering, assumptions and expectations about identity and ask questions about home, belonging and migration, mother tongue and translation. I draw inspiration from Korean American artist Theresa Hak Kyung Cha's use of texts, documents and images to explore dislocation and memory, as well as authors who engage language, translation and belonging such as Mikhail Shishkin, Yoko Tawada, Gloria Anzaldua and Mohammed Khair-Eddine.
- Full Text:
- Date Issued: 2017
- Authors: Asfour, Fouad-Martin
- Date: 2017
- Subjects: Creative writing (Higher education) South Africa , South African fiction (English) 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7190 , vital:21227
- Description: Written in non-linear fragments, my thesis is what Audre Lorde in her novel Zami calls a "biomythography" - the weaving together of myth, history and biography in epic narrative form, a style of composition that represents all the ways in which we perceive the world. Using repetition and shifting memories, I draw from my bicultural upbringing in Offenbach, a city in Germany populated mostly by migrants, as well as my experience of working in art and culture internationally, travelling and living in different countries. Interrogating objects, buildings, family photographs, books and movies, and listening to the silences of the unvoiced, I upset and play with experiences of othering, assumptions and expectations about identity and ask questions about home, belonging and migration, mother tongue and translation. I draw inspiration from Korean American artist Theresa Hak Kyung Cha's use of texts, documents and images to explore dislocation and memory, as well as authors who engage language, translation and belonging such as Mikhail Shishkin, Yoko Tawada, Gloria Anzaldua and Mohammed Khair-Eddine.
- Full Text:
- Date Issued: 2017
Identification of SNPs within the CYP2A6 enzyme of TNBC cell lines and the resulting change in activity
- Dingle, Laura Margaret Kirkpatrick
- Authors: Dingle, Laura Margaret Kirkpatrick
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64349 , vital:28536
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2017
- Authors: Dingle, Laura Margaret Kirkpatrick
- Date: 2017
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64349 , vital:28536
- Description: Expected release date-May 2019
- Full Text:
- Date Issued: 2017
Identifying growth criteria and sediment movement mechanisms of needle ice using high-frequency environmental and visual monitoring
- Authors: Borg, Carl-Johan
- Date: 2017
- Subjects: Frazil ice , Sediment transport , Ice mechanics , Photography -- Digital techniques , Environmental monitoring
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/17656 , vital:22268
- Description: Environmental growth conditions and mechanisms involved in sediment transport by needle ice have historically been difficult to assess and are poorly documented. The spatial and temporal dynamics that relate to the environment, growth and decay of needle ice are not fully understood. This study monitored needle ice growth, melt and visually identified sediment displacement mechanisms by needle ice, with the aim of revealing environmental growth criteria, timing of growth/melt, ground-surface-air energy balance and sediment displacement mechanisms. Furthermore, the impact of needle ice displacement on vegetation and patterned ground formation was analysed. High-frequency visual monitoring, using three cameras, supplemented by high-frequency measurements of air temperature, soil moisture and wind speed was used to investigate needle ice growth and decay dynamics. Results from visual and environmental monitoring of needle ice growth, showed that the needle ice growing environment was more dynamic, especially in terms of surface temperature, than previously argued. Needle ice growth was observed to occur during surface temperatures from -2.0°C to 2.2°C, soil moisture levels from 0.4% to 37.4% and in winds speeds of 0 m/s to 12.6 m/s. Needle ice initiation was documented a few minutes to hours before or after the onset of surface temperature dropping to below 0°C. Imagery displayed that the depth of ice nucleation was variable within the soil column, possibly relating to the energy balance of radiative cooling, convective heat loss, ground conductivity and latent heat release at the air-surface-ground boundary. Heaving and resettling, toppling and rolling were identified as slope displacement mechanisms when needle ice decayed. Animal trampling and hail were additionally documented as substantial surface altering processes. Furthermore, no impact of needle ice reducing vegetation stability was identified, although a tendency to hinder vegetation expansion was noted. Also, no creation of patterned ground was observed as a result of needle ice decay.
- Full Text:
- Date Issued: 2017
- Authors: Borg, Carl-Johan
- Date: 2017
- Subjects: Frazil ice , Sediment transport , Ice mechanics , Photography -- Digital techniques , Environmental monitoring
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/17656 , vital:22268
- Description: Environmental growth conditions and mechanisms involved in sediment transport by needle ice have historically been difficult to assess and are poorly documented. The spatial and temporal dynamics that relate to the environment, growth and decay of needle ice are not fully understood. This study monitored needle ice growth, melt and visually identified sediment displacement mechanisms by needle ice, with the aim of revealing environmental growth criteria, timing of growth/melt, ground-surface-air energy balance and sediment displacement mechanisms. Furthermore, the impact of needle ice displacement on vegetation and patterned ground formation was analysed. High-frequency visual monitoring, using three cameras, supplemented by high-frequency measurements of air temperature, soil moisture and wind speed was used to investigate needle ice growth and decay dynamics. Results from visual and environmental monitoring of needle ice growth, showed that the needle ice growing environment was more dynamic, especially in terms of surface temperature, than previously argued. Needle ice growth was observed to occur during surface temperatures from -2.0°C to 2.2°C, soil moisture levels from 0.4% to 37.4% and in winds speeds of 0 m/s to 12.6 m/s. Needle ice initiation was documented a few minutes to hours before or after the onset of surface temperature dropping to below 0°C. Imagery displayed that the depth of ice nucleation was variable within the soil column, possibly relating to the energy balance of radiative cooling, convective heat loss, ground conductivity and latent heat release at the air-surface-ground boundary. Heaving and resettling, toppling and rolling were identified as slope displacement mechanisms when needle ice decayed. Animal trampling and hail were additionally documented as substantial surface altering processes. Furthermore, no impact of needle ice reducing vegetation stability was identified, although a tendency to hinder vegetation expansion was noted. Also, no creation of patterned ground was observed as a result of needle ice decay.
- Full Text:
- Date Issued: 2017
Implementing the annual national assessment at an ordinary public primary school in the Eastern Cape: a case study analysis
- Authors: Lascelles, Philippa Anne
- Date: 2017
- Subjects: Educational tests and measurements -- South Africa , Educational tests and measurements -- South Africa -- Case studies , Education, Elementary -- South Africa , Elementary schools -- South Africa -- Makhanda
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/7713 , vital:21288
- Description: This empirical study describes in rich detail five teachers’ perceptions of the Annual National Assessment [ANA] at one level of the school system (Grade Three of the Foundation Phase [FP]) at an ordinary public primary school in an urban area of the Eastern Cape. Secondly, the study described the process of preparing for, implementing and assessing the 2014 ANA at the selected school. In order to generate insights for a deep understanding of how teachers perceive, prepare for and implement the ANA, the challenges that arise, and how the ANA is impacting on curriculum and pedagogy, an interpretive qualitative research approach and case study method were adopted. The researcher, a participant observer operating from an insider position, used ethnographic techniques to describe, document and analyse teachers’ perceptions and experiences of implementing the 2014 ANA tests in a specific context (one school) and at one level of the school system (Grade 3). Data gathered through observations, semi-structured interviews and document analysis were coded and analysed in order to identify emerging themes. These are compared to trends and developments in contemporary literature on educational assessment. The findings revealed that while the teachers were compliant and efficient in their implementation and administration of the ANA, they have a narrow perception of the ANA as a summative assessment serving systemic purposes. There was little, if any, evidence of them using the ANA for the formative assessment purposes intended by policy. As a result, opportunities for using the ANA to enhance teaching and learning were lost. The study illuminated the roles and responsibilities of the teachers, the school management team and Eastern Cape [EC] Department of Education [DoE] in the ANA preparation and implementation process, and the need for strengthening the support provided by the EC DoE. Although context specific, the study sheds light on how Grade 3 teachers in an ordinary public school perceive and implement the ANA. The insights afforded and lessons that can be learned from this case study may be relevant to other Foundation Phase school contexts.
- Full Text:
- Date Issued: 2017
- Authors: Lascelles, Philippa Anne
- Date: 2017
- Subjects: Educational tests and measurements -- South Africa , Educational tests and measurements -- South Africa -- Case studies , Education, Elementary -- South Africa , Elementary schools -- South Africa -- Makhanda
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/7713 , vital:21288
- Description: This empirical study describes in rich detail five teachers’ perceptions of the Annual National Assessment [ANA] at one level of the school system (Grade Three of the Foundation Phase [FP]) at an ordinary public primary school in an urban area of the Eastern Cape. Secondly, the study described the process of preparing for, implementing and assessing the 2014 ANA at the selected school. In order to generate insights for a deep understanding of how teachers perceive, prepare for and implement the ANA, the challenges that arise, and how the ANA is impacting on curriculum and pedagogy, an interpretive qualitative research approach and case study method were adopted. The researcher, a participant observer operating from an insider position, used ethnographic techniques to describe, document and analyse teachers’ perceptions and experiences of implementing the 2014 ANA tests in a specific context (one school) and at one level of the school system (Grade 3). Data gathered through observations, semi-structured interviews and document analysis were coded and analysed in order to identify emerging themes. These are compared to trends and developments in contemporary literature on educational assessment. The findings revealed that while the teachers were compliant and efficient in their implementation and administration of the ANA, they have a narrow perception of the ANA as a summative assessment serving systemic purposes. There was little, if any, evidence of them using the ANA for the formative assessment purposes intended by policy. As a result, opportunities for using the ANA to enhance teaching and learning were lost. The study illuminated the roles and responsibilities of the teachers, the school management team and Eastern Cape [EC] Department of Education [DoE] in the ANA preparation and implementation process, and the need for strengthening the support provided by the EC DoE. Although context specific, the study sheds light on how Grade 3 teachers in an ordinary public school perceive and implement the ANA. The insights afforded and lessons that can be learned from this case study may be relevant to other Foundation Phase school contexts.
- Full Text:
- Date Issued: 2017
Improving the cold tolerance of false codling moth, thaumatotibia leucotreta, for better performance in a sterile insect release programme
- Authors: Daniel, Claire Ashleigh
- Date: 2017
- Subjects: Cryptophlebia leucotreta -- South Africa , Cryptophlebia leucotreta -- Reproduction -- Effect of temperature on , Cryptophlebia leucotreta -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Insecticides , Citrus fruit industry -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5271 , vital:20803
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a major pest of citrus and other important crops in Sub-Saharan Africa. The introduction of a sterile insect technique (SIT) programme for FCM in South Africa has proven to be very effective in the control of FCM. The objective was to flood citrus orchards with large numbers of sterile males resulting in a ratio of at least 10 sterile to 1 wild moth, increasing the probability of a female moth mating with a sterile male. This target is often achieved and the programme is generally successful, however there are some challenges regarding this programme. The mass rearing environment, artificial diet, handling methods and irradiation have an impact on sterile insect quality as environmental differences between the rearing facility and field, influences the insect phenotype and competitiveness. This is evident as wild male moths can theoretically actively fly at a temperature of 12°C and laboratory-reared sterilized moths, due to the radiation treatment, appear unable to fly below 20°C. As a consequence, sterile males are out-competed by wild males during the cooler months of the year. This is detrimental to the SIT programme as FCM do not undergo diapause, meaning they are active during winter and will still reproduce. Therefore, to maximize the effect of the SIT programme, it is vital to increase the flight ability of mass reared sterile males at lower temperatures. Various studies have shown that by adding cryoprotectants to the basic laboratory diets increases the cold tolerance of certain insects and thus may allow them to be mobile at lower temperatures, however it imperative that any chemical used to augment the commercial diet of the insect has no negative effects on the insect physiology and development. To investigate this detail for FCM, five generations of FCM were reared on diets augmented with various known insect cryoprotectants. These augmented FCM were subsequently used in experiments designed to determine firstly, if the cryoprotectants had a positive result on the cold tolerance of the FCM, and secondly, if they had any adverse effects on other physiological aspects such as duration of development. Laboratory trials indicated that the flight ability of male FCM was improved when larvae were reared on diets augmented with trehalose and cholesterol (with an average of 40 % of cholesterol and trehalose augmented males that flew at 15 °C where 0 % of the control flew). Results obtained during the field trials support the laboratory results as there was a significant increase in the number of trehalose augmented moths caught in the field during March and July (winter). Results also showed potential for cholesterol to be used as an additive. Other important findings show that both cholesterol and trehalose have no negative impacts on developmental rate, pupal size, and egg production and viability. Trehalose was found to increase the pupal mass of male and female FCM, as well as the number of eggs laid per female. Cholesterol was found to increase developmental rate and the number of eggs laid. The main findings of this study were that diet additives could improve the massrearing of FCM for SIT and the competitiveness of the males, especially at lower temperatures. However, the additives were expensive and cost could well be a constraint to the wide scale implementation of the new technology.
- Full Text:
- Date Issued: 2017
- Authors: Daniel, Claire Ashleigh
- Date: 2017
- Subjects: Cryptophlebia leucotreta -- South Africa , Cryptophlebia leucotreta -- Reproduction -- Effect of temperature on , Cryptophlebia leucotreta -- Biological control -- South Africa , Citrus -- Diseases and pests -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Insecticides , Citrus fruit industry -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5271 , vital:20803
- Description: The false codling moth (FCM), Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is a major pest of citrus and other important crops in Sub-Saharan Africa. The introduction of a sterile insect technique (SIT) programme for FCM in South Africa has proven to be very effective in the control of FCM. The objective was to flood citrus orchards with large numbers of sterile males resulting in a ratio of at least 10 sterile to 1 wild moth, increasing the probability of a female moth mating with a sterile male. This target is often achieved and the programme is generally successful, however there are some challenges regarding this programme. The mass rearing environment, artificial diet, handling methods and irradiation have an impact on sterile insect quality as environmental differences between the rearing facility and field, influences the insect phenotype and competitiveness. This is evident as wild male moths can theoretically actively fly at a temperature of 12°C and laboratory-reared sterilized moths, due to the radiation treatment, appear unable to fly below 20°C. As a consequence, sterile males are out-competed by wild males during the cooler months of the year. This is detrimental to the SIT programme as FCM do not undergo diapause, meaning they are active during winter and will still reproduce. Therefore, to maximize the effect of the SIT programme, it is vital to increase the flight ability of mass reared sterile males at lower temperatures. Various studies have shown that by adding cryoprotectants to the basic laboratory diets increases the cold tolerance of certain insects and thus may allow them to be mobile at lower temperatures, however it imperative that any chemical used to augment the commercial diet of the insect has no negative effects on the insect physiology and development. To investigate this detail for FCM, five generations of FCM were reared on diets augmented with various known insect cryoprotectants. These augmented FCM were subsequently used in experiments designed to determine firstly, if the cryoprotectants had a positive result on the cold tolerance of the FCM, and secondly, if they had any adverse effects on other physiological aspects such as duration of development. Laboratory trials indicated that the flight ability of male FCM was improved when larvae were reared on diets augmented with trehalose and cholesterol (with an average of 40 % of cholesterol and trehalose augmented males that flew at 15 °C where 0 % of the control flew). Results obtained during the field trials support the laboratory results as there was a significant increase in the number of trehalose augmented moths caught in the field during March and July (winter). Results also showed potential for cholesterol to be used as an additive. Other important findings show that both cholesterol and trehalose have no negative impacts on developmental rate, pupal size, and egg production and viability. Trehalose was found to increase the pupal mass of male and female FCM, as well as the number of eggs laid per female. Cholesterol was found to increase developmental rate and the number of eggs laid. The main findings of this study were that diet additives could improve the massrearing of FCM for SIT and the competitiveness of the males, especially at lower temperatures. However, the additives were expensive and cost could well be a constraint to the wide scale implementation of the new technology.
- Full Text:
- Date Issued: 2017
In silico analysis of plasmodium falciparum Hsp70-x for potential binding sites and hits
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
- Date Issued: 2017
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
- Date Issued: 2017
Indigenous and traditional musics in the school classroom : a re-evaluation of the South African Indigenous African Music (IAM) curriculum
- Authors: McConnachie, Boudina
- Date: 2017
- Subjects: Ethnomusicology , Indigenous people -- Music , Music -- Instruction and study -- Africa , Music -- Instruction and study -- Curricula -- Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21182 , http://hdl.handle.net/10962/6806
- Description: Musical ideals set by European standards and values, entrenched through colonial oppression and promoted by the continued veneration of Western culture need to be re-evaluated. Despite the intention of the ANC government, through the Department of Basic Education's Curriculum and Assessment Policy Statement music curricula, to integrate Indigenous Knowledge and musics into the South African classroom, evidence shows that opportunities to do so are not seized. With reference to the proclaimed values of an African sensibility in the model of the South African music education curriculum, the history of its development and the current pedagogical movement towards transformation in the production of knowledge and the inclusion of Indigenous Knowledge (IK), this thesis questions why teachers in government schools in South Africa are not executing the Indigenous African Music (IAM) syllabus in the CAPS FET music curriculum. Taking the history of music education and the development of curriculum models and frameworks into account, it interrogates what strategies could improve the application of the current music curriculum in government schools in South Africa. These questions are addressed in the thesis by way of a discussion of the music curriculum and what its praxis in the classroom reveals about its efficacy, through observations and personal experiences, the observations of teachers and student teachers, a comparison with the experience in Zimbabwe, and an analysis of the music curriculum as it is currently devised and implemented. Straddling three methodological approaches, namely the ethnographic, the autoethnographic and the action research approach this study finds that the CAPS FET music curriculum does provide realistic opportunities to engage with African Indigenous and traditional music. This, however, is dependent upon the training of the teacher, facilities available in the classroom and the prior knowledge of the learner. A fundamental flaw of this curriculum is the approach to practical assessment of Indigenous and traditional African musics and the lack of assessment criteria and practical guidelines. In addition, the findings suggest that the fault regarding implementation of the curriculum lies in the training of students (who become teachers) at tertiary level, where an integrated approach to skills development regarding Indigenous African music is suggested.
- Full Text:
- Date Issued: 2017
- Authors: McConnachie, Boudina
- Date: 2017
- Subjects: Ethnomusicology , Indigenous people -- Music , Music -- Instruction and study -- Africa , Music -- Instruction and study -- Curricula -- Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:21182 , http://hdl.handle.net/10962/6806
- Description: Musical ideals set by European standards and values, entrenched through colonial oppression and promoted by the continued veneration of Western culture need to be re-evaluated. Despite the intention of the ANC government, through the Department of Basic Education's Curriculum and Assessment Policy Statement music curricula, to integrate Indigenous Knowledge and musics into the South African classroom, evidence shows that opportunities to do so are not seized. With reference to the proclaimed values of an African sensibility in the model of the South African music education curriculum, the history of its development and the current pedagogical movement towards transformation in the production of knowledge and the inclusion of Indigenous Knowledge (IK), this thesis questions why teachers in government schools in South Africa are not executing the Indigenous African Music (IAM) syllabus in the CAPS FET music curriculum. Taking the history of music education and the development of curriculum models and frameworks into account, it interrogates what strategies could improve the application of the current music curriculum in government schools in South Africa. These questions are addressed in the thesis by way of a discussion of the music curriculum and what its praxis in the classroom reveals about its efficacy, through observations and personal experiences, the observations of teachers and student teachers, a comparison with the experience in Zimbabwe, and an analysis of the music curriculum as it is currently devised and implemented. Straddling three methodological approaches, namely the ethnographic, the autoethnographic and the action research approach this study finds that the CAPS FET music curriculum does provide realistic opportunities to engage with African Indigenous and traditional music. This, however, is dependent upon the training of the teacher, facilities available in the classroom and the prior knowledge of the learner. A fundamental flaw of this curriculum is the approach to practical assessment of Indigenous and traditional African musics and the lack of assessment criteria and practical guidelines. In addition, the findings suggest that the fault regarding implementation of the curriculum lies in the training of students (who become teachers) at tertiary level, where an integrated approach to skills development regarding Indigenous African music is suggested.
- Full Text:
- Date Issued: 2017
Information and propaganda in the federation of Rhodesia and Nyasaland with special reference to print and radio propaganda for Africans, 1953-1963
- Authors: Zimudzi, Tapiwa Brown
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6957 , vital:21204
- Description: This thesis contributes to the history of the information and propaganda policy and practice of the government of the Federation of Rhodesia and Nyasaland by examining this government's pro-Federation print and radio propaganda for Africans in the Federation. Using a multi-theoretical approach, it analyses the character of this propaganda, highlighting its main methods and themes as well as the policy considerations, plus political and economic circumstances that gave rise to it. It also discusses how Africans in the Federation reacted to this propaganda and assesses its effectiveness in gaining the support of these Africans for Federation and the policies of the Federal government. The thesis argues that Federal government propaganda aimed at gaining the support of Africans for Federation was predominantly panic-driven propaganda and was the product of an information panic that lay at the heart of the very idea of Federation itself. This information panic arose out of the Federal government's belated recognition of the strength of African opposition to Federation and of how this opposition seriously threatened the continued survival of the Federation. It is also argued that this panic-driven pro-Federation propaganda elicited largely hostile reactions from the majority of Africans in the Federation and failed to persuade them to support Federation.
- Full Text:
- Date Issued: 2017
- Authors: Zimudzi, Tapiwa Brown
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6957 , vital:21204
- Description: This thesis contributes to the history of the information and propaganda policy and practice of the government of the Federation of Rhodesia and Nyasaland by examining this government's pro-Federation print and radio propaganda for Africans in the Federation. Using a multi-theoretical approach, it analyses the character of this propaganda, highlighting its main methods and themes as well as the policy considerations, plus political and economic circumstances that gave rise to it. It also discusses how Africans in the Federation reacted to this propaganda and assesses its effectiveness in gaining the support of these Africans for Federation and the policies of the Federal government. The thesis argues that Federal government propaganda aimed at gaining the support of Africans for Federation was predominantly panic-driven propaganda and was the product of an information panic that lay at the heart of the very idea of Federation itself. This information panic arose out of the Federal government's belated recognition of the strength of African opposition to Federation and of how this opposition seriously threatened the continued survival of the Federation. It is also argued that this panic-driven pro-Federation propaganda elicited largely hostile reactions from the majority of Africans in the Federation and failed to persuade them to support Federation.
- Full Text:
- Date Issued: 2017
Inhalable particulate systems for anti-tubercular drug delivery
- Nkanga, Christian Isalomboto
- Authors: Nkanga, Christian Isalomboto
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/37966 , vital:24720
- Description: Tuberculosis (TB) is a deadly infectious microbial disease that is currently dominating public health concerns. Among the pharmacological issues in the management of TB are the poor bioavailability of some anti-TB drugs, mostly due to the fast first-pass metabolism, and high drug load needed for combination therapy. These result in a lengthy treatment with several adverse effects causing decreased patient compliance. These factors often lead to the therapeutic failure and promote the development of drug resistant strains, justifying the urgent need for new therapeutic strategies. Liposomes are lipid-based particulate vehicles known to be the most clinically appointed drug carriers currently. Liposomal systems are reported to be rapidly engulfed by macrophages - where the mycobacterium often resides. This makes liposomes appropriate vehicles for targeted anti-TB drug delivery. Many research groups have reported the potential of liposomes systems to deliver anti-TB drugs. However, the costly formulation status of liposomes, due the use of expensive synthetic or highly purified natural phospholipids, is a limitation to the treatment of a poverty related infectious disease like TB. The aim of this study was to design and develop liposomes for pulmonary delivery of anti-TB drugs using crude soybean lecithin (CL) and its purirified version. CL is an FDA- approved naturally occurring phospholipid mixture that is quite cheap and readily available. Various liposome batches were prepared using a film hydration method and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Liposomes composed of CL and cholesterol (Chol) in a 3:1 mass ratio were selected for drug encapsulation based on the following characteristics: polydispersity index (PDI, 0.28), mean particles sizes (PS, 502 nm) and zeta potential (ZP, -56 mV). Isoniazid (INH) was encapsulated as a model drug using a freeze-thaw loading technique and an HPLC method was validated for quantitative analysis. The physicochemical properties of INH-loaded liposomes were comprehensively investigated using thermal, microscopy and spectroscopic techniques. This formulation showed a high encapsulation efficiency (%EE) of 78%, much better than the liposomes made from purified lecithin, 20%. Other characteristics of INH- loaded liposomes, which make them attractive for pulmonary TB therapy, are presented in this dissertation. These include a controlled release of 50% of the encapsulated INH over 12 hours. Finally, rifampicin (RIF) was added as a hydrophobic model drug and several evaluations were conducted on these dual drug-loaded liposomes. Of particular interest, it was noted that the dual drug-loaded liposomes made of CL alone showed the highest %EE (59% for INH and 90% for RIF) compared to those containing Chol or those made of purified lecithin. Surprisingly, the average PS of the dual CL-based liposomes (1114 nm) was in the size range reported for optimum deep lung deposition and macrophage uptake. In addition, the mean ZP of these liposomes (-63 mV) seems to be favourable for their shelf stability and internalization by macrophages. Overall, these findings show that the dual CL-based liposomes developed would be promising for macrophage-targeting pulmonary delivery of anti-TB drugs.
- Full Text:
- Date Issued: 2017
- Authors: Nkanga, Christian Isalomboto
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/37966 , vital:24720
- Description: Tuberculosis (TB) is a deadly infectious microbial disease that is currently dominating public health concerns. Among the pharmacological issues in the management of TB are the poor bioavailability of some anti-TB drugs, mostly due to the fast first-pass metabolism, and high drug load needed for combination therapy. These result in a lengthy treatment with several adverse effects causing decreased patient compliance. These factors often lead to the therapeutic failure and promote the development of drug resistant strains, justifying the urgent need for new therapeutic strategies. Liposomes are lipid-based particulate vehicles known to be the most clinically appointed drug carriers currently. Liposomal systems are reported to be rapidly engulfed by macrophages - where the mycobacterium often resides. This makes liposomes appropriate vehicles for targeted anti-TB drug delivery. Many research groups have reported the potential of liposomes systems to deliver anti-TB drugs. However, the costly formulation status of liposomes, due the use of expensive synthetic or highly purified natural phospholipids, is a limitation to the treatment of a poverty related infectious disease like TB. The aim of this study was to design and develop liposomes for pulmonary delivery of anti-TB drugs using crude soybean lecithin (CL) and its purirified version. CL is an FDA- approved naturally occurring phospholipid mixture that is quite cheap and readily available. Various liposome batches were prepared using a film hydration method and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Liposomes composed of CL and cholesterol (Chol) in a 3:1 mass ratio were selected for drug encapsulation based on the following characteristics: polydispersity index (PDI, 0.28), mean particles sizes (PS, 502 nm) and zeta potential (ZP, -56 mV). Isoniazid (INH) was encapsulated as a model drug using a freeze-thaw loading technique and an HPLC method was validated for quantitative analysis. The physicochemical properties of INH-loaded liposomes were comprehensively investigated using thermal, microscopy and spectroscopic techniques. This formulation showed a high encapsulation efficiency (%EE) of 78%, much better than the liposomes made from purified lecithin, 20%. Other characteristics of INH- loaded liposomes, which make them attractive for pulmonary TB therapy, are presented in this dissertation. These include a controlled release of 50% of the encapsulated INH over 12 hours. Finally, rifampicin (RIF) was added as a hydrophobic model drug and several evaluations were conducted on these dual drug-loaded liposomes. Of particular interest, it was noted that the dual drug-loaded liposomes made of CL alone showed the highest %EE (59% for INH and 90% for RIF) compared to those containing Chol or those made of purified lecithin. Surprisingly, the average PS of the dual CL-based liposomes (1114 nm) was in the size range reported for optimum deep lung deposition and macrophage uptake. In addition, the mean ZP of these liposomes (-63 mV) seems to be favourable for their shelf stability and internalization by macrophages. Overall, these findings show that the dual CL-based liposomes developed would be promising for macrophage-targeting pulmonary delivery of anti-TB drugs.
- Full Text:
- Date Issued: 2017
Integrating Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR) for greater local level resilience: lessons from a multi-stakeholder think-tank
- Pereira, Taryn, Shackleton, Sheona E, Donkor, Felix Kwabena
- Authors: Pereira, Taryn , Shackleton, Sheona E , Donkor, Felix Kwabena
- Date: 2017
- Subjects: Climatic changes -- South Africa , Climatic changes -- South Africa -- Eastern Cape -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/62027 , vital:28097
- Description: The last few years have seen one of the most severe droughts in recent times in the southern African region, and news headlines are increasingly full of warnings about heavy storms, fires and floods. There is no doubt that extreme hydro-meteorological events, and their multiple and potentially disastrous impacts, are at the forefront of the public consciousness at the present time and are one of the key concerns regarding the impacts of climate change in the region. While the links between extreme climate events, disaster risk reduction (DRR - see Box 1) and climate change adaptation (CCA - see Box 2) are recognised in the South African Climate Change White Paper, this is not the case for the whole region. Furthermore, even if there is national recognition of the need to synergise these two spheres of endeavour, this does not always trickle down to effective policy, planning and implementation at the local level.
- Full Text:
- Date Issued: 2017
- Authors: Pereira, Taryn , Shackleton, Sheona E , Donkor, Felix Kwabena
- Date: 2017
- Subjects: Climatic changes -- South Africa , Climatic changes -- South Africa -- Eastern Cape -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/62027 , vital:28097
- Description: The last few years have seen one of the most severe droughts in recent times in the southern African region, and news headlines are increasingly full of warnings about heavy storms, fires and floods. There is no doubt that extreme hydro-meteorological events, and their multiple and potentially disastrous impacts, are at the forefront of the public consciousness at the present time and are one of the key concerns regarding the impacts of climate change in the region. While the links between extreme climate events, disaster risk reduction (DRR - see Box 1) and climate change adaptation (CCA - see Box 2) are recognised in the South African Climate Change White Paper, this is not the case for the whole region. Furthermore, even if there is national recognition of the need to synergise these two spheres of endeavour, this does not always trickle down to effective policy, planning and implementation at the local level.
- Full Text:
- Date Issued: 2017
Integrating local indigenous knowledge in the teaching of water conservation by senior primary school Natural Science teachers: a Namibian case study
- Authors: Visagie, Ronald Arnold
- Date: 2017
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/6907 , vital:21199
- Description: The conservation of biodiversity to meet the needs and aspirations of present and future generations is a cornerstone for sustainable development. In response to this, one of the aims of Basic Education in Namibia is to develop an environmentally friendly society which has a concern for the conservation of water. Thus, the National Curriculum of Basic Education [NCBE], 2010, p. 8) expects Grade 6 Natural Science learners to be competent in using simple scientific models, methods and skills to make scientific sense of the natural environment; and most importantly for the learners to relate the implications of this scientific understanding to their personal and social health and the sustainable use of all natural resources for future generations. Additionally, teachers are encouraged to make innovative use of various knowledge systems including indigenous knowledge. However, there is no mention of how teachers should make use of local indigenous knowledge (IK) when teaching the topic on water conservation in particular. It is against this backdrop that in this study I sought to understand how two Grade 6 Natural Science teachers use local indigenous knowledge in their classrooms to teach the topic of water conservation. This interpretive case study was carried out in collaboration with a rural community in the Erongo region. Data were collected in three stages. The first stage was the gathering of information through document analysis to strengthen my context. Documents such as the National Curriculum, Science Curriculum, Syllabi, Grade 6 Natural Science textbooks and SATs results were analysed to gain some insight and understanding of the issue before conducting interviews. In the second phase of this study I conducted semi-structured interviews with the Topnaar community members and two teachers. This was followed by classroom observations. Additionally, I used stimulated recall interviews (SRI) to provide clarity on how teachers use prior knowledge and mediate learning when teaching the topic water conservation using indigenous knowledge. The study is informed by Vygotsky’s (1978) socio-cultural theory in conjunction with Shulman’s (1986) pedagogical content knowledge (PCK). Since a classroom is a social unit where interactions occur between teachers and learners, and learners and learners, these theories provided a useful lens for observing lessons and analysing teachers’ content knowledge and how they mediate learning using local indigenous knowledge. A thematic approach to data analysis was adopted and qualitative data were analysed inductively. The findings of the study revealed that the indigenous knowledge amongst the Topnaars are governed by the ideals of Ubuntu. Findings also revealed that proper planning is needed to incorporate IK into science lessons as it may clear up misconceptions that may arise from indigenous knowledge. The study recommends that teachers and curriculum planners should explore different indigenous practices that are linked to the topics in the curriculum or syllabus to enhance learning and teaching in their science classrooms. It also recommends that curriculum developers, with the help of subject advisors, teachers and community members, should start planning on how indigenous knowledge can best be integrated into science textbooks as it has become a hindrance for the teachers to incorporate it.
- Full Text:
- Date Issued: 2017
- Authors: Visagie, Ronald Arnold
- Date: 2017
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/6907 , vital:21199
- Description: The conservation of biodiversity to meet the needs and aspirations of present and future generations is a cornerstone for sustainable development. In response to this, one of the aims of Basic Education in Namibia is to develop an environmentally friendly society which has a concern for the conservation of water. Thus, the National Curriculum of Basic Education [NCBE], 2010, p. 8) expects Grade 6 Natural Science learners to be competent in using simple scientific models, methods and skills to make scientific sense of the natural environment; and most importantly for the learners to relate the implications of this scientific understanding to their personal and social health and the sustainable use of all natural resources for future generations. Additionally, teachers are encouraged to make innovative use of various knowledge systems including indigenous knowledge. However, there is no mention of how teachers should make use of local indigenous knowledge (IK) when teaching the topic on water conservation in particular. It is against this backdrop that in this study I sought to understand how two Grade 6 Natural Science teachers use local indigenous knowledge in their classrooms to teach the topic of water conservation. This interpretive case study was carried out in collaboration with a rural community in the Erongo region. Data were collected in three stages. The first stage was the gathering of information through document analysis to strengthen my context. Documents such as the National Curriculum, Science Curriculum, Syllabi, Grade 6 Natural Science textbooks and SATs results were analysed to gain some insight and understanding of the issue before conducting interviews. In the second phase of this study I conducted semi-structured interviews with the Topnaar community members and two teachers. This was followed by classroom observations. Additionally, I used stimulated recall interviews (SRI) to provide clarity on how teachers use prior knowledge and mediate learning when teaching the topic water conservation using indigenous knowledge. The study is informed by Vygotsky’s (1978) socio-cultural theory in conjunction with Shulman’s (1986) pedagogical content knowledge (PCK). Since a classroom is a social unit where interactions occur between teachers and learners, and learners and learners, these theories provided a useful lens for observing lessons and analysing teachers’ content knowledge and how they mediate learning using local indigenous knowledge. A thematic approach to data analysis was adopted and qualitative data were analysed inductively. The findings of the study revealed that the indigenous knowledge amongst the Topnaars are governed by the ideals of Ubuntu. Findings also revealed that proper planning is needed to incorporate IK into science lessons as it may clear up misconceptions that may arise from indigenous knowledge. The study recommends that teachers and curriculum planners should explore different indigenous practices that are linked to the topics in the curriculum or syllabus to enhance learning and teaching in their science classrooms. It also recommends that curriculum developers, with the help of subject advisors, teachers and community members, should start planning on how indigenous knowledge can best be integrated into science textbooks as it has become a hindrance for the teachers to incorporate it.
- Full Text:
- Date Issued: 2017
Interactions between two biological control agents released on Pereskia aculeata Miller (Cactaceae), in South Africa
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
- Date Issued: 2017
- Authors: Mnqeta, Zezethu
- Date: 2017
- Subjects: Pereskia aculeata -- Biological control , Cactus -- Biological control -- South Africa , Alien plants -- Biological control -- South Africa , Flea beetles -- South Africa , Coreidae -- South Africa , Insects as biological pest control agents -- South Africa
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7949 , vital:21327
- Description: Pereskia aculeata Miller (Cactaceae) is an alien invasive plant introduced into South Africa from Brazil, which has negative impacts on native biodiversity in South Africa. Phenrica guerini Bechyne (Chrysomelidae) and Catorhintha schaffneri Brailovsky & Garcia (Coreidae) are two biological control agents released against P. aculeata in South Africa. Phenrica guerini was first released against P. aculeata, in 1991, followed by C. schaffneri in 2014. The overall aim of this study was to improve the biological control programme against P. aculeata in order to decrease its density to a level where it does not threaten the native biodiversity of South Africa. The first part of this study evaluated the efficacy of P. guerini on P. aculeata at Port Alfred (Eastern Cape) to better understand the role of P. guerini in the biological control of P. aculeata. An insecticide exclusion experiment was conducted over 100 days. Plots with P. guerini had a mean of 187 (SE ± 62) fewer leaves/m2 than plots without P. guerini. The agent reduced percentage cover in plots with P. guerini, with a mean of 19.42% (SE ± 3.15) lower cover than plots without P. guerini. Although P. guerini had an impact on P. aculeata at Port Alfred previous studies have indicated that a reduction to below 50% cover is required for native biodiversity to recover and the agent only reduced cover to 62% at Port Alfred. Phenrica guerini has therefore not reduced percentage cover sufficiently to completely control the weed. The data collected from Port Alfred was compared to the performance of the agent nationwide. Although P. guerini was found at far more sites than previously recorded, there were very few sites with comparable levels of damage to Port Alfred. This evidence suggests that P. guerini is not sufficiently damaging to reduce P. aculeata to acceptable levels and other biological control agents should be considered.Interactions between two biological control agents can have complex and unexpected impacts for a biological control programme. The second part of this study was to investigate interactions between C. schaffneri and P. guerini under laboratory conditions to test whether the two agents, individually or jointly, enhanced or reduced their impact on P. aculeata. Potted P. aculeata plants were exposed to one of four treatments: control (no agents), P. guerini only, C. schaffneri only and both species in combination. Four stocking densities, ranging from 2 to 12 insects per plant were used. Catorhintha schaffneri alone at high densities was more damaging than all other treatments with a significantly greater reduction in the mean number of leaves, 11.7 (SE ± 1.29), and shoot lengths, 2.17cm (SE ± O. 75). Even at lower density treatments, the combination of the two agents was not significantly more damaging than C. schaffneri alone and C. schaffneri was always more damaging than P. guerini alone. Mortality of P. guerini was significantly higher than C. schaffneri at the highest stocking density when in combination. Phenrica guerini contributes towards the biological control of P. aculeata at some sites in South Africa but not enough to completely control the weed. The antagonistic interaction between P. guerini and C. schaffneri suggests that these agents should not be released together because this would impact negatively on the overall biocontrol programme against P. aculeata. Catorhintha schaffneri should be released at sites were P. guerini is not present and evaluations of the success of this agent in the field should be conducted. Extrapolation of laboratory-based studies into the field is often challenging so mass-rearing of P. guerini should continue until there is convincing proof that C. schaffneri alone is more effective than P. guerini in the field.
- Full Text:
- Date Issued: 2017
Intergenerational learning and environmental care: a case of a fishing community next to Africa’s first marine protected area
- Authors: Cloete, Cindy-Lee
- Date: 2017
- Subjects: Tsitsikamma Marine Protected Area (South Africa) , Covie (South Africa) , Intergenerational relations -- South Africa -- Covie , Intergenerational communication -- South Africa -- Covie , Fishing villages -- South Africa -- Covie , Sustainable fisheries -- South Africa -- Covie , Environmental education -- South Africa -- Covie
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/7598 , vital:21277
- Description: This study explored the relationship between intergenerational learning and environmental care in the small fishing community of Covie, located next to the Tsitsikamma Marine Protected Area (TMPA) on the south-eastern coast of South Africa. Since Covie’s establishment as a woodcutter settlement in 1883, the community has depended on the marine and coastal environment such that their communal identity and basic means of subsistence are closely tied to their traditional fishing practices. Since its proclamation in 1964, the TMPA has undergone numerous policy changes, most notably the complete closure of the TMPA to fishing in 2001. Against this backdrop, the study sought to understand how intergenerational learning about fishing practices are mediated in Covie and the ways in which such learning processes constitute a sense of place and belonging for the Covie fishers, and to develop a sense of care for the natural environment. The study included 12 Covie community members of different generations and genders so as to be representative of the community (approximately 86 members). The research was informed by qualitative data generated through a focus group discussion with eight Covie community members, a mirror workshop with the same eight community members, eight semi-structured interviews, and five naturalistic observations of fishing practices. Data generation and analysis was informed by Etienne Wenger’s theory of Communities of Practice which was complemented by theoretical perspectives on intergenerational learning and attachment to place. This study found that the Covie fishers indeed operate as a community of practice who depend significantly on intergenerational learning processes to transfer knowledge, skills and values about fishing practices to younger generations. The 2001 policy changes that denied the Covie fishers access to their traditional fishing sites were shown to reduce the participation in fishing of a range of community members (in particular children and women), which in turn influenced forms of intergenerational learning about fishing. The youth’s reduced participation especially was linked to more protracted and fragmented processes of learning about fishing and Covie’s code of fishing conduct, including its underpinning sense of environmental care. Finally, this study argues that the affective and socio-material connections to their natural surroundings have shaped the Covie community’s sense of care and responsibility toward the environment.
- Full Text:
- Date Issued: 2017
- Authors: Cloete, Cindy-Lee
- Date: 2017
- Subjects: Tsitsikamma Marine Protected Area (South Africa) , Covie (South Africa) , Intergenerational relations -- South Africa -- Covie , Intergenerational communication -- South Africa -- Covie , Fishing villages -- South Africa -- Covie , Sustainable fisheries -- South Africa -- Covie , Environmental education -- South Africa -- Covie
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/7598 , vital:21277
- Description: This study explored the relationship between intergenerational learning and environmental care in the small fishing community of Covie, located next to the Tsitsikamma Marine Protected Area (TMPA) on the south-eastern coast of South Africa. Since Covie’s establishment as a woodcutter settlement in 1883, the community has depended on the marine and coastal environment such that their communal identity and basic means of subsistence are closely tied to their traditional fishing practices. Since its proclamation in 1964, the TMPA has undergone numerous policy changes, most notably the complete closure of the TMPA to fishing in 2001. Against this backdrop, the study sought to understand how intergenerational learning about fishing practices are mediated in Covie and the ways in which such learning processes constitute a sense of place and belonging for the Covie fishers, and to develop a sense of care for the natural environment. The study included 12 Covie community members of different generations and genders so as to be representative of the community (approximately 86 members). The research was informed by qualitative data generated through a focus group discussion with eight Covie community members, a mirror workshop with the same eight community members, eight semi-structured interviews, and five naturalistic observations of fishing practices. Data generation and analysis was informed by Etienne Wenger’s theory of Communities of Practice which was complemented by theoretical perspectives on intergenerational learning and attachment to place. This study found that the Covie fishers indeed operate as a community of practice who depend significantly on intergenerational learning processes to transfer knowledge, skills and values about fishing practices to younger generations. The 2001 policy changes that denied the Covie fishers access to their traditional fishing sites were shown to reduce the participation in fishing of a range of community members (in particular children and women), which in turn influenced forms of intergenerational learning about fishing. The youth’s reduced participation especially was linked to more protracted and fragmented processes of learning about fishing and Covie’s code of fishing conduct, including its underpinning sense of environmental care. Finally, this study argues that the affective and socio-material connections to their natural surroundings have shaped the Covie community’s sense of care and responsibility toward the environment.
- Full Text:
- Date Issued: 2017
Invasion status and potential impacts of bluegill Lepomis macrochirus Rafinesque, 1819 in the Kariega River, Eastern Cape, South Africa
- Authors: Ndaleni, Phumza Malibongwe
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7586 , vital:21276
- Description: The impact of alien invasive species is one of the greatest threats to biodiversity globally. All of the major drainages of South Africa are invaded by non-native fishes, yet little information is available on their impact. This thesis focusses on providing a better understanding of the potential impacts of bluegill Lepomis macrochirus Rafinesque, 1819, a species introduced into South Africa from the USA in 1938. The study assesses the distribution, establishment success and feeding ecology of L. macrochirus in an invaded South African River system in order to better understand and document its potential impacts. Specifically; this thesis (1) assesses the distribution and relative abundance of L. macrochirus in the Kariega System of the Eastern Cape, (2) determines the diet of the species in one of the major impoundments of the system, and (3) uses an experimental comparative functional response approach to assess whether this species has heightened predatory capabilities when compared with fishes with which it cooccurs. Ninety-six sites in the Kariega River system were sampled from the headwaters down to the estuary. Small native fish species (Enteromius anoplus and Enteromius pallidus) occurred mostly in the upper reaches, while in the middle and lower reaches, the centrarchid alien largemouth bass Micropterus salmoides and bluegill L. mocrochirus dominated. There was overlap between the centrarchids and introduced banded tilapia Tilapia sparrmanii and southern mouthbrooder Pseudocrenilabrus philander, but never with small-bodied native species. The stomach contents of L. macrochirus were examined during winter and summer and prey were identified to family level. Crustaceans and insects were an important component in their diet, but in summer fish eggs were common. Comparisons of bluegill diet with published literature indicated that there was potential for competition with largemouth bass, banded tilapia and southern mouthbrooder. Feeding experiments were conducted to compare the functional responses of these four species using a common prey item. Banded tilapia had significantly lower attack rates than the other species with no significant difference observed in other species. Bluegill has a similar impact to that of banded tilapia and southern mouthbrooder, but lower than that of largemouth bass. Results of the present study highlight that L. macrochirus introduced into dams will likely result in both upstream and downstream invasion of river systems. It is likely that this species does not, however, have as much of a predatory impact as M. salmoides in that its predatory capacity is relatively reduced and more comparable to South African native cichlids. These results are discussed within the context of invasion success/failure in other regions of southern Africa.
- Full Text:
- Date Issued: 2017
- Authors: Ndaleni, Phumza Malibongwe
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/7586 , vital:21276
- Description: The impact of alien invasive species is one of the greatest threats to biodiversity globally. All of the major drainages of South Africa are invaded by non-native fishes, yet little information is available on their impact. This thesis focusses on providing a better understanding of the potential impacts of bluegill Lepomis macrochirus Rafinesque, 1819, a species introduced into South Africa from the USA in 1938. The study assesses the distribution, establishment success and feeding ecology of L. macrochirus in an invaded South African River system in order to better understand and document its potential impacts. Specifically; this thesis (1) assesses the distribution and relative abundance of L. macrochirus in the Kariega System of the Eastern Cape, (2) determines the diet of the species in one of the major impoundments of the system, and (3) uses an experimental comparative functional response approach to assess whether this species has heightened predatory capabilities when compared with fishes with which it cooccurs. Ninety-six sites in the Kariega River system were sampled from the headwaters down to the estuary. Small native fish species (Enteromius anoplus and Enteromius pallidus) occurred mostly in the upper reaches, while in the middle and lower reaches, the centrarchid alien largemouth bass Micropterus salmoides and bluegill L. mocrochirus dominated. There was overlap between the centrarchids and introduced banded tilapia Tilapia sparrmanii and southern mouthbrooder Pseudocrenilabrus philander, but never with small-bodied native species. The stomach contents of L. macrochirus were examined during winter and summer and prey were identified to family level. Crustaceans and insects were an important component in their diet, but in summer fish eggs were common. Comparisons of bluegill diet with published literature indicated that there was potential for competition with largemouth bass, banded tilapia and southern mouthbrooder. Feeding experiments were conducted to compare the functional responses of these four species using a common prey item. Banded tilapia had significantly lower attack rates than the other species with no significant difference observed in other species. Bluegill has a similar impact to that of banded tilapia and southern mouthbrooder, but lower than that of largemouth bass. Results of the present study highlight that L. macrochirus introduced into dams will likely result in both upstream and downstream invasion of river systems. It is likely that this species does not, however, have as much of a predatory impact as M. salmoides in that its predatory capacity is relatively reduced and more comparable to South African native cichlids. These results are discussed within the context of invasion success/failure in other regions of southern Africa.
- Full Text:
- Date Issued: 2017
Invasive alien plants and rural livelihoods: a case of Gwanda District, Zimbabwe
- Authors: Dube, Nqobizitha
- Date: 2017
- Subjects: Cylindropuntia fulgida , Invasive plants -- Economic aspects , Invasive plants -- Control , Invasive plants -- Economic aspects -- Zimbabwe , Ecosystem services -- Zimbabwe , Environmental policy -- Zimbabwe , Ecosystem management -- Zimbabwe , Cactus -- Economic aspects -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/4368 , vital:20653
- Description: Biodiversity is the cornerstone of ecosystem functioning and the realisation that most rural African community livelihoods are directly dependent on ecosystem goods and services warrants its conservation. Invasive alien plants threaten biodiversity and compromise the ecosystem's ability to provide goods and services for rural communities, thereby negatively affecting livelihood strategies. Information on IAPs is lacking in most African countries, thus, the livelihood effects of Invasive Alien Plants (IAPs) are not clearly understood. In Zimbabwe, Cylindropuntia fulgida var. fulgida (Cff) has invaded Gwanda district in the Matabeleland south province compromising local household capital assets that contribute to livelihood strategies and altering the ecosystem. This study exposed the rural worldview of the environment, the effect that Cff has on local livelihood strategies and the effectiveness environmental management institutions in rural Gwanda district. The study followed a post positivist paradigm. The impacts of IAPs on rural communities in Zimbabwe were analysed by looking at the livelihood stresses that arise because of Cff. The research used multi-stage sampling to select a representative sample of respondents. Primary data was collected using semi-structured questionnaires, group discussion and key informant guides. Furthermore, document analysis was conducted to collect secondary data. The data analysis process used Computer packages Microsoft Excel, SPSS and NVIVO. Results showed that livelihood benefits that species in the natural environment provide strongly influence environmental perceptions of rural African communities. Additionally, the study showed that Cff compromises the local ecosystem and reduces its ability to support the dominant livelihoods in the study area. The long-term result of such a situation in the absence of control is increased poverty and the failure to realise sustainable development. However, results indicated that IAPs could also improve the poverty situation of a community before they have reached the threshold points. It is therefore imperative to know the threshold points of an invasive plant in order to ascertain the efficient point to intervene. The study also showed that benefits of invasive plants accrue to different members of a society at different times (private/public). This knowledge allows the adoption of efficient and effective control strategies.
- Full Text:
- Date Issued: 2017
- Authors: Dube, Nqobizitha
- Date: 2017
- Subjects: Cylindropuntia fulgida , Invasive plants -- Economic aspects , Invasive plants -- Control , Invasive plants -- Economic aspects -- Zimbabwe , Ecosystem services -- Zimbabwe , Environmental policy -- Zimbabwe , Ecosystem management -- Zimbabwe , Cactus -- Economic aspects -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/4368 , vital:20653
- Description: Biodiversity is the cornerstone of ecosystem functioning and the realisation that most rural African community livelihoods are directly dependent on ecosystem goods and services warrants its conservation. Invasive alien plants threaten biodiversity and compromise the ecosystem's ability to provide goods and services for rural communities, thereby negatively affecting livelihood strategies. Information on IAPs is lacking in most African countries, thus, the livelihood effects of Invasive Alien Plants (IAPs) are not clearly understood. In Zimbabwe, Cylindropuntia fulgida var. fulgida (Cff) has invaded Gwanda district in the Matabeleland south province compromising local household capital assets that contribute to livelihood strategies and altering the ecosystem. This study exposed the rural worldview of the environment, the effect that Cff has on local livelihood strategies and the effectiveness environmental management institutions in rural Gwanda district. The study followed a post positivist paradigm. The impacts of IAPs on rural communities in Zimbabwe were analysed by looking at the livelihood stresses that arise because of Cff. The research used multi-stage sampling to select a representative sample of respondents. Primary data was collected using semi-structured questionnaires, group discussion and key informant guides. Furthermore, document analysis was conducted to collect secondary data. The data analysis process used Computer packages Microsoft Excel, SPSS and NVIVO. Results showed that livelihood benefits that species in the natural environment provide strongly influence environmental perceptions of rural African communities. Additionally, the study showed that Cff compromises the local ecosystem and reduces its ability to support the dominant livelihoods in the study area. The long-term result of such a situation in the absence of control is increased poverty and the failure to realise sustainable development. However, results indicated that IAPs could also improve the poverty situation of a community before they have reached the threshold points. It is therefore imperative to know the threshold points of an invasive plant in order to ascertain the efficient point to intervene. The study also showed that benefits of invasive plants accrue to different members of a society at different times (private/public). This knowledge allows the adoption of efficient and effective control strategies.
- Full Text:
- Date Issued: 2017
Investigating herbivory and plant origin on tall-statured grasses in South Africa
- Authors: Canavan, Kim
- Date: 2017
- Subjects: Insects as biological pest control agents -- South Africa , Arundo donax , Giant reed -- South Africa , Giant reed -- Biological control -- South Africa , Phragmites australis , Phragmites mauritianus , Phragmites , Tetramesa romana , Biological invasions -- South Africa , Wasps -- Host plants , Wasps -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6147 , vital:21051
- Description: South African riparian zones have been heavily degraded through anthropogenic activities such as dam construction and extraction of water for irrigation, which has resulted in a loss of ecosystem services and functioning. A consequence of such disturbances to riparian areas is in their susceptibility to invasive alien species (IAS). One such IAS is the giant reed, Arundo donax L. (Poaceae), introduced to South Africa in the 1700s largely for erosion control. Arundo donax has since greatly expanded in the country and is now one of the most abundant IAS. Arundo donax has been found to displace native vegetation and in South Africa this will most likely lead to the displacement of the native tall-statured grasses, Phragmites australis (Cav.) Trin. ex Steud. and Phragmites mauritianus Kunth. This study aimed to enhance our understanding of the tall-statured grasses A. donax, P. australis and P. mauritianus to better manage them in riparian areas. For A. donax, biological control is seen as the most viable option to control stands in the long-term. However, before such a programme is put in place, it is important to first collect baseline data that can be used to guide the direction of the biological control project in South Africa. For the Phragmites spp., despite being a dominant vegetative type in riparian areas, very little is known about their status in South Africa. Furthermore, there have been increasing reports of both Phragmites species having an expansion of their range and abundance. In North America, there has been a similar trend of reed expansion and through molecular work it was determined that a cryptic invasion has occurred with the introduction of an invasive non-native haplotype from Europe. It is therefore unknown if Phragmites spp. populations are expanding due to anthropogenic activities or due to a cryptic invasion. To address these shortfalls in knowledge the study investigated the tall-statured grasses in two parts; firstly, molecular techniques are used to explore the plant origin and genetic diversity of A. donax, P. australis and P. mauritianus and secondly using the Enemy Release Hypothesis as a framework, herbivore assemblages for each reed was determined across their distribution in South Africa. Molecular-techniques determined that both P. australis and P. mauritianus had only one haplotype - known as haplotype K and haplotype V respectively, across their distribution. For P. australis, haplotype K shares a close connection with populations from a Mediterranean lineage and this was further confirmed with a shared grass-waxy band. The direction and timing of genetic exchange between the two regions could not be ascertained and thus still remains unknown. Microsatellite analysis determined that both Phragmites spp. had a high genetic diversity compared to worldwide lineages. With no evidence of any cryptic invasions of haplotypes from other regions, both Phragmites spp. populations are likely to be native to South Africa. For A. donax all populations across South Africa were determined to be haplotype M1; a cosmopolitan haplotype that has an ancient native range in Afghanistan and Pakistan (Indus Valley). Populations were found to have no genetic diversity and thus can be considered one clone. A pre-introductory survey determined a list of herbivores associated with each tall- statured grass. For A. donax, a total of seven herbivores were found. Of these, one herbivore, a galling wasp, Tetramesa romana Walker (Hymenoptera: Eurytomidae) was found to be highly abundant and widely distributed in South Africa. Tetramesa romana is already a biological control agent in North America and thus is likely exerting some pressure on A. donax populations in South Africa. For both Phragmites spp. a total of ten herbivores were found, although having higher species richness compared to A. donax, when compared to other regions, these native species have a relatively low species richness. Providing baseline data on plant origin, genetic diversity and herbivory on A. donax, P. australis and P. mauritianus has provided important information on managing these species in riparian ecosystems in South Africa. For the Phragmites spp. with no evidence of any cryptic invasions, it is recommended that reed stands continue to be managed as native species. Phragmites spp. are important dominant vegetative species and thus should be protected; however, if reed stands become expansive, control methods can be put in place to focus on managing spread and abundance. For A. donax, this study was able to provide pivotal information in guiding the biological control programme. By determining the ancient lineage of South African populations, research can be focused in this area to find potential biological control agents. Lastly, the pre-introductory survey determined that a biological control agent, T. romana was already established with an unknown introduction and also highlighted potential plant parts that should be targeted. In particular, no rhizome feeding herbivores were found in South Africa and therefore this highlights an important niche that should be explored in biological control agents.
- Full Text:
- Date Issued: 2017
- Authors: Canavan, Kim
- Date: 2017
- Subjects: Insects as biological pest control agents -- South Africa , Arundo donax , Giant reed -- South Africa , Giant reed -- Biological control -- South Africa , Phragmites australis , Phragmites mauritianus , Phragmites , Tetramesa romana , Biological invasions -- South Africa , Wasps -- Host plants , Wasps -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6147 , vital:21051
- Description: South African riparian zones have been heavily degraded through anthropogenic activities such as dam construction and extraction of water for irrigation, which has resulted in a loss of ecosystem services and functioning. A consequence of such disturbances to riparian areas is in their susceptibility to invasive alien species (IAS). One such IAS is the giant reed, Arundo donax L. (Poaceae), introduced to South Africa in the 1700s largely for erosion control. Arundo donax has since greatly expanded in the country and is now one of the most abundant IAS. Arundo donax has been found to displace native vegetation and in South Africa this will most likely lead to the displacement of the native tall-statured grasses, Phragmites australis (Cav.) Trin. ex Steud. and Phragmites mauritianus Kunth. This study aimed to enhance our understanding of the tall-statured grasses A. donax, P. australis and P. mauritianus to better manage them in riparian areas. For A. donax, biological control is seen as the most viable option to control stands in the long-term. However, before such a programme is put in place, it is important to first collect baseline data that can be used to guide the direction of the biological control project in South Africa. For the Phragmites spp., despite being a dominant vegetative type in riparian areas, very little is known about their status in South Africa. Furthermore, there have been increasing reports of both Phragmites species having an expansion of their range and abundance. In North America, there has been a similar trend of reed expansion and through molecular work it was determined that a cryptic invasion has occurred with the introduction of an invasive non-native haplotype from Europe. It is therefore unknown if Phragmites spp. populations are expanding due to anthropogenic activities or due to a cryptic invasion. To address these shortfalls in knowledge the study investigated the tall-statured grasses in two parts; firstly, molecular techniques are used to explore the plant origin and genetic diversity of A. donax, P. australis and P. mauritianus and secondly using the Enemy Release Hypothesis as a framework, herbivore assemblages for each reed was determined across their distribution in South Africa. Molecular-techniques determined that both P. australis and P. mauritianus had only one haplotype - known as haplotype K and haplotype V respectively, across their distribution. For P. australis, haplotype K shares a close connection with populations from a Mediterranean lineage and this was further confirmed with a shared grass-waxy band. The direction and timing of genetic exchange between the two regions could not be ascertained and thus still remains unknown. Microsatellite analysis determined that both Phragmites spp. had a high genetic diversity compared to worldwide lineages. With no evidence of any cryptic invasions of haplotypes from other regions, both Phragmites spp. populations are likely to be native to South Africa. For A. donax all populations across South Africa were determined to be haplotype M1; a cosmopolitan haplotype that has an ancient native range in Afghanistan and Pakistan (Indus Valley). Populations were found to have no genetic diversity and thus can be considered one clone. A pre-introductory survey determined a list of herbivores associated with each tall- statured grass. For A. donax, a total of seven herbivores were found. Of these, one herbivore, a galling wasp, Tetramesa romana Walker (Hymenoptera: Eurytomidae) was found to be highly abundant and widely distributed in South Africa. Tetramesa romana is already a biological control agent in North America and thus is likely exerting some pressure on A. donax populations in South Africa. For both Phragmites spp. a total of ten herbivores were found, although having higher species richness compared to A. donax, when compared to other regions, these native species have a relatively low species richness. Providing baseline data on plant origin, genetic diversity and herbivory on A. donax, P. australis and P. mauritianus has provided important information on managing these species in riparian ecosystems in South Africa. For the Phragmites spp. with no evidence of any cryptic invasions, it is recommended that reed stands continue to be managed as native species. Phragmites spp. are important dominant vegetative species and thus should be protected; however, if reed stands become expansive, control methods can be put in place to focus on managing spread and abundance. For A. donax, this study was able to provide pivotal information in guiding the biological control programme. By determining the ancient lineage of South African populations, research can be focused in this area to find potential biological control agents. Lastly, the pre-introductory survey determined that a biological control agent, T. romana was already established with an unknown introduction and also highlighted potential plant parts that should be targeted. In particular, no rhizome feeding herbivores were found in South Africa and therefore this highlights an important niche that should be explored in biological control agents.
- Full Text:
- Date Issued: 2017
Investigating how Grade 10 Physical Science teachers help learners to make sense of concepts of electromagnetism using easily accessible materials in under-resourced schools
- Authors: Samuel, Paulo
- Date: 2017
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8143 , vital:21359
- Description: This study sought to explore teachers’ perceptions and experiences of using easily accessible materials and how they might collaboratively develop learning and teaching support materials using easily accessible materials. The study explored three aspects. Firstly, the views, experiences and factors which influence grade 10 Physical Science teachers’ perceptions and experiences of teaching the topic of electromagnetism. Secondly, to find out what teachers can do to improve teaching and learning of electromagnetism in grade 10 Physical Science using easily accessible materials. Thirdly, to look at what enables or constrains grade 10 Physical Science teachers in under-resourced schools when dealing with electromagnetism, from using easily accessible materials. A qualitative method approach was adopted, underpinned by an interpretive paradigm but using some quantitative methods as well. Within the interpretive paradigm a case study approach was used. The study was carried out in Swakopmund and Gobabis education circuits of the Erongo and Omaheke Regions respectively. Data were collected using questionnaires, lesson observations and stimulated-recall interviews. The data obtained were validated in two ways, firstly, by triangulation from different data gathering techniques, and secondly, validation was done by member checking of the transcripts. To make meaning from the data generated, Vygotsky’s (1978) socio-cultural theory was used as a lens to analyse the data. The quantitative data generated were presented in figures, tables; whereas the qualitative data were coded inductively into descriptive texts to make meaning. It was found that teachers’s perceptions and experiences are that the topic of electromagnetism is quite challenging. Teachers reported that their learners find it difficult to comprehend phenomena associated with electromagnetism, thus making it difficult for their learners to grasp concepts associated with it. Lack of resources to do practical activities in the topic of electromagnetism was found to be a major contributing factor to teaching and learning of this topic. The use of easily accessible materials among teachers was found to be very limited. Easily accessible locally sourced materials were found to have the potential to enable grade 10 Physical Science teachers to help learners to make sense of concepts of electromagnetism in under-resourced schools. In light of the above findings, the study recommends that science teachers should make use of easily accessible materials which can minimise their dependence on standard laboratory equipment which is unaffordable anyway by most schools.
- Full Text:
- Date Issued: 2017
- Authors: Samuel, Paulo
- Date: 2017
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8143 , vital:21359
- Description: This study sought to explore teachers’ perceptions and experiences of using easily accessible materials and how they might collaboratively develop learning and teaching support materials using easily accessible materials. The study explored three aspects. Firstly, the views, experiences and factors which influence grade 10 Physical Science teachers’ perceptions and experiences of teaching the topic of electromagnetism. Secondly, to find out what teachers can do to improve teaching and learning of electromagnetism in grade 10 Physical Science using easily accessible materials. Thirdly, to look at what enables or constrains grade 10 Physical Science teachers in under-resourced schools when dealing with electromagnetism, from using easily accessible materials. A qualitative method approach was adopted, underpinned by an interpretive paradigm but using some quantitative methods as well. Within the interpretive paradigm a case study approach was used. The study was carried out in Swakopmund and Gobabis education circuits of the Erongo and Omaheke Regions respectively. Data were collected using questionnaires, lesson observations and stimulated-recall interviews. The data obtained were validated in two ways, firstly, by triangulation from different data gathering techniques, and secondly, validation was done by member checking of the transcripts. To make meaning from the data generated, Vygotsky’s (1978) socio-cultural theory was used as a lens to analyse the data. The quantitative data generated were presented in figures, tables; whereas the qualitative data were coded inductively into descriptive texts to make meaning. It was found that teachers’s perceptions and experiences are that the topic of electromagnetism is quite challenging. Teachers reported that their learners find it difficult to comprehend phenomena associated with electromagnetism, thus making it difficult for their learners to grasp concepts associated with it. Lack of resources to do practical activities in the topic of electromagnetism was found to be a major contributing factor to teaching and learning of this topic. The use of easily accessible materials among teachers was found to be very limited. Easily accessible locally sourced materials were found to have the potential to enable grade 10 Physical Science teachers to help learners to make sense of concepts of electromagnetism in under-resourced schools. In light of the above findings, the study recommends that science teachers should make use of easily accessible materials which can minimise their dependence on standard laboratory equipment which is unaffordable anyway by most schools.
- Full Text:
- Date Issued: 2017