Opportunity and constraint : historicity, hybridity and notions of cultural identity among farm workers in the Sundays River Valley
- Authors: Connor, Teresa Kathleen
- Date: 2007
- Subjects: Agricultural laborers -- South Africa -- Relocation Addo Elephant National Park (South Africa) Xhosa (African people) -- South Africa -- Eastern Cape -- Ethnic identity Forced migration -- South Africa -- Eastern Cape Land settlement -- South Africa -- Government policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2117 , http://hdl.handle.net/10962/d1008367
- Description: This thesis focuses on relationships of opportunity and constraint among farm workers in the Sundays River Valley (SRV), Eastern Cape Province. Relationships of 'constraint' include those experiences of displacement and forced removal and war, including forced removals by the apartheid state in 1960 and 1970. Relationships of 'opportunity' include the ways in which residents in the SRV have contested their experiences of upheaval and domination, and the formation of a regional sense of place and belonging/ investigate how farm workers actually draw elements of locality and identity from their experiences of upheaval, and how displacement bolsters feelings of belonging and place. Instead of viewing displacement as a once-off experience, this thesis investigates displacement in historical terms, as a long-term, 'serial' experience of human movement, which is continued in the present- specifically through the creation of the Greater Addo Elephant National Park. I concentrate on developing a spatialised and cultural notion of movemenUplacement. 'Place' is investigated as a term that refers to rather indeterminate feelings of nostalgia, memory and identity, which depend on a particular connection to territory (ie: 'space'). I emphasise that elements of place in the SRV are drawn from and expressed along dualistic lines, which juxtapose situations of opportunity and constraint. In this way, farm workers' sense of connection to farms and ancestral territory in the SRV depends on their experiences of stable residency and work on farms, as well as their memories of removal from land in the area. I emphasise that those elements of conservatism (expressed as 'tradition' and Redness) among Xhosa-speaking farm workers are indications of a certain hybridity of identity in the region, which depend on differentiation from other groups (such as so-called 'coloured' farm workers and 'white' farmers), as well as associations between these groups. This thesis lays emphasis upon those less visible and definable 'identities' in the Eastern Cape Province, specifically by shifting focus away from the exhomeland states of the Ciskei and Transkei, to more marginal expressions of identity and change (among farm workers) in the Province. I point out that labourers cannot solely be defined by their positions as farm workers, but by their place and sense of cultural belonging in the area. In this sense, I use the idea of work as a loaded concept that can comment on a range of cultural attitudes towards belonging and place, and which is firmly embedded in the private lives of labourers - beyond their simple socio-economic conditions of farm work. I use Bourdieu's conception of habitus and doxa to define work as a set of dispositions that have been historicised and internalised by workers to such an extent, that relationships of domination are sometimes inadvertently obscured through their apparent 'naturalness'. Moreover, I point out that work can be related to ritualised action in the SRV through the use of performance and practice-based anthropological theory. Both work and ritual are symbolic actions, and are sites of struggle within which workers express themselves dualistically. Rituals, specifically, are dramatic events that combine disharmonious and harmonious social processes - juxtaposing the powerlessness of workers (on farms), and the deep sense of belonging and place in the SRV. I argue that the deep historical connections in the SRV have largely been ignored by conservationists in the drive to establish new protected zones (such as the Greater Addo Elephant National Park), and that a new model of shared conservation management is needed for this Park.
- Full Text:
- Date Issued: 2007
- Authors: Connor, Teresa Kathleen
- Date: 2007
- Subjects: Agricultural laborers -- South Africa -- Relocation Addo Elephant National Park (South Africa) Xhosa (African people) -- South Africa -- Eastern Cape -- Ethnic identity Forced migration -- South Africa -- Eastern Cape Land settlement -- South Africa -- Government policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2117 , http://hdl.handle.net/10962/d1008367
- Description: This thesis focuses on relationships of opportunity and constraint among farm workers in the Sundays River Valley (SRV), Eastern Cape Province. Relationships of 'constraint' include those experiences of displacement and forced removal and war, including forced removals by the apartheid state in 1960 and 1970. Relationships of 'opportunity' include the ways in which residents in the SRV have contested their experiences of upheaval and domination, and the formation of a regional sense of place and belonging/ investigate how farm workers actually draw elements of locality and identity from their experiences of upheaval, and how displacement bolsters feelings of belonging and place. Instead of viewing displacement as a once-off experience, this thesis investigates displacement in historical terms, as a long-term, 'serial' experience of human movement, which is continued in the present- specifically through the creation of the Greater Addo Elephant National Park. I concentrate on developing a spatialised and cultural notion of movemenUplacement. 'Place' is investigated as a term that refers to rather indeterminate feelings of nostalgia, memory and identity, which depend on a particular connection to territory (ie: 'space'). I emphasise that elements of place in the SRV are drawn from and expressed along dualistic lines, which juxtapose situations of opportunity and constraint. In this way, farm workers' sense of connection to farms and ancestral territory in the SRV depends on their experiences of stable residency and work on farms, as well as their memories of removal from land in the area. I emphasise that those elements of conservatism (expressed as 'tradition' and Redness) among Xhosa-speaking farm workers are indications of a certain hybridity of identity in the region, which depend on differentiation from other groups (such as so-called 'coloured' farm workers and 'white' farmers), as well as associations between these groups. This thesis lays emphasis upon those less visible and definable 'identities' in the Eastern Cape Province, specifically by shifting focus away from the exhomeland states of the Ciskei and Transkei, to more marginal expressions of identity and change (among farm workers) in the Province. I point out that labourers cannot solely be defined by their positions as farm workers, but by their place and sense of cultural belonging in the area. In this sense, I use the idea of work as a loaded concept that can comment on a range of cultural attitudes towards belonging and place, and which is firmly embedded in the private lives of labourers - beyond their simple socio-economic conditions of farm work. I use Bourdieu's conception of habitus and doxa to define work as a set of dispositions that have been historicised and internalised by workers to such an extent, that relationships of domination are sometimes inadvertently obscured through their apparent 'naturalness'. Moreover, I point out that work can be related to ritualised action in the SRV through the use of performance and practice-based anthropological theory. Both work and ritual are symbolic actions, and are sites of struggle within which workers express themselves dualistically. Rituals, specifically, are dramatic events that combine disharmonious and harmonious social processes - juxtaposing the powerlessness of workers (on farms), and the deep sense of belonging and place in the SRV. I argue that the deep historical connections in the SRV have largely been ignored by conservationists in the drive to establish new protected zones (such as the Greater Addo Elephant National Park), and that a new model of shared conservation management is needed for this Park.
- Full Text:
- Date Issued: 2007
Population structure, growth and recruitment of two exploited infralittoral molluscs (Haliotis midae and Turbo sarmaticus) along the south east coast, South Africa
- Authors: Proudfoot, Lee-Anne
- Date: 2007
- Subjects: Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5744 , http://hdl.handle.net/10962/d1005430 , Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Description: The two most frequently exploited species along the south east coast of South Africa are the gastropods, Haliotis midae (abalone) and Turbo sarmaticus (alikreukel). H. midae is a high valued commercial species, and suffers intense levels of illegal fishing. T. sarmaticus however, has no commercial value but is the preferred food item for impoverished subsistence communities. Owing to the fact that no legal commercial fishery exists for either species along the south coast, very few studies have been undertaken, especially in the heavily exploited infralittoral. Infralittoral size frequency distributions for both species revealed significant variation in density and size among sites of varying exploitation pressure. Densities ranged between 0 – 2.23 m⁻² (H. midae) and 0.03 – 4.93 m⁻² (T. sarmaticus) and maximum shell lengths ranged from 49.4 – 153.5 mm (H. midae) and 28.3 – 104.4 mm (T. sarmaticus). Relatively high densities and large sizes were found in marine reserves and secluded areas, and low densities and small sizes at sites near to large population centres and within the former Ciskei homeland region. Mean size of the largest 10% of the population, total density and sexually mature density were significantly related to exploitation predictors for both species. In addition, densities of H. midae juveniles were significantly related to exploitation predictors, suggesting that recruitment may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tended to be localized with refuge and subtidal populations persisting. H. midae exploitation was however, far more extensive and intense. Growth of H. midae was investigated using three methods; mark-recapture, cohort analysis and growth banding analysis at Kowie Rocks, Port Alfred. The most useful of these methods for determining growth was a new technique described for growth banding analysis; which was validated using cohort analysis and measurements of shells of known age. This technique was less time consuming and labour intensive than previously described methods. Abalone growth was best described by the Schnute (1981) growth function. Systematic geographic variation in growth was observed for 10 sites along the South African coastline. Significant differences in growth among sites existed for animals between 0-4 years (P < 0.0001) and 4-6 years (P < 0.0001), and in the mean maximum sizes attained (P < 0.001). In general, abalone from the south east/east coast were found to have faster growth rates, smaller mean maximum sizes and attained sexual maturity earlier than those along the south west/ west coast. Haliotis midae recruit and juvenile densities were found to differ significantly among sites of varying exploitation pressure (P < 0.0001) and among months for recruit densities (P < 0.001). Exploited sites had low recruit and juvenile densities compared to unexploited sites and peak recruitment occurred during October/ November 2005. Recruit densities were significantly related to infralittoral adult densities during two of the three sampling months (P<0.05), when recruitment was low. No relationship was observed during the period of high recruitment, with all sites receiving high recruit densities. It was concluded that variation in recruit densities was the result of a combination of both density-dependent relationships (i.e. local spawner density and temporal variability in recruitment intensity) and the possible dispersal capabilities of H. midae. In addition, it was concluded that at present recruitment overfishing was not occurring along the south east coast. Post-recruitment mortality rates were variable but relatively constant, with hypothetical percentage survival and density curves revealing high rates and similar mortality curves among sites. Variation in juvenile densities was consequently a result of initial recruit densities and not variation in post-recruitment mortality. T. sarmaticus populations were found to be regionally sustainable and persisted along the south east coast due to adjacent intertidal and subtidal refuge populations. However, H. midae populations are becoming decimated along the south east coast. From the information obtained in this study new management proposals were suggested and discussed, such as closed areas and region-based management fisheries together with stock enhancement. These suggestions may prove to be feasible alternatives to present management strategies.
- Full Text:
- Date Issued: 2007
- Authors: Proudfoot, Lee-Anne
- Date: 2007
- Subjects: Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5744 , http://hdl.handle.net/10962/d1005430 , Abalones -- South Africa , Abalones -- Growth -- South Africa , Turbinidae -- South Africa , Mollusks -- South Africa
- Description: The two most frequently exploited species along the south east coast of South Africa are the gastropods, Haliotis midae (abalone) and Turbo sarmaticus (alikreukel). H. midae is a high valued commercial species, and suffers intense levels of illegal fishing. T. sarmaticus however, has no commercial value but is the preferred food item for impoverished subsistence communities. Owing to the fact that no legal commercial fishery exists for either species along the south coast, very few studies have been undertaken, especially in the heavily exploited infralittoral. Infralittoral size frequency distributions for both species revealed significant variation in density and size among sites of varying exploitation pressure. Densities ranged between 0 – 2.23 m⁻² (H. midae) and 0.03 – 4.93 m⁻² (T. sarmaticus) and maximum shell lengths ranged from 49.4 – 153.5 mm (H. midae) and 28.3 – 104.4 mm (T. sarmaticus). Relatively high densities and large sizes were found in marine reserves and secluded areas, and low densities and small sizes at sites near to large population centres and within the former Ciskei homeland region. Mean size of the largest 10% of the population, total density and sexually mature density were significantly related to exploitation predictors for both species. In addition, densities of H. midae juveniles were significantly related to exploitation predictors, suggesting that recruitment may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tended to be localized with refuge and subtidal populations persisting. H. midae exploitation was however, far more extensive and intense. Growth of H. midae was investigated using three methods; mark-recapture, cohort analysis and growth banding analysis at Kowie Rocks, Port Alfred. The most useful of these methods for determining growth was a new technique described for growth banding analysis; which was validated using cohort analysis and measurements of shells of known age. This technique was less time consuming and labour intensive than previously described methods. Abalone growth was best described by the Schnute (1981) growth function. Systematic geographic variation in growth was observed for 10 sites along the South African coastline. Significant differences in growth among sites existed for animals between 0-4 years (P < 0.0001) and 4-6 years (P < 0.0001), and in the mean maximum sizes attained (P < 0.001). In general, abalone from the south east/east coast were found to have faster growth rates, smaller mean maximum sizes and attained sexual maturity earlier than those along the south west/ west coast. Haliotis midae recruit and juvenile densities were found to differ significantly among sites of varying exploitation pressure (P < 0.0001) and among months for recruit densities (P < 0.001). Exploited sites had low recruit and juvenile densities compared to unexploited sites and peak recruitment occurred during October/ November 2005. Recruit densities were significantly related to infralittoral adult densities during two of the three sampling months (P<0.05), when recruitment was low. No relationship was observed during the period of high recruitment, with all sites receiving high recruit densities. It was concluded that variation in recruit densities was the result of a combination of both density-dependent relationships (i.e. local spawner density and temporal variability in recruitment intensity) and the possible dispersal capabilities of H. midae. In addition, it was concluded that at present recruitment overfishing was not occurring along the south east coast. Post-recruitment mortality rates were variable but relatively constant, with hypothetical percentage survival and density curves revealing high rates and similar mortality curves among sites. Variation in juvenile densities was consequently a result of initial recruit densities and not variation in post-recruitment mortality. T. sarmaticus populations were found to be regionally sustainable and persisted along the south east coast due to adjacent intertidal and subtidal refuge populations. However, H. midae populations are becoming decimated along the south east coast. From the information obtained in this study new management proposals were suggested and discussed, such as closed areas and region-based management fisheries together with stock enhancement. These suggestions may prove to be feasible alternatives to present management strategies.
- Full Text:
- Date Issued: 2007
Rehabilitation of the Orange River Mouth Salt Marsh : seed, wind and sediment characteristics
- Authors: Shaw, Gregory Alan
- Date: 2007
- Subjects: Salt marshes -- Orange River , Rivers -- South Africa -- Environmental aspects , Orange River -- Ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10626 , http://hdl.handle.net/10948/603 , http://hdl.handle.net/10948/d1012010 , Salt marshes -- Orange River , Rivers -- South Africa -- Environmental aspects , Orange River -- Ecology
- Description: The Orange River is an important source of freshwater and like many other wetlands in semi-arid regions, supports various social (Spurgeon, 1998), economic (Spurgeon, 1998; Bornman et al., 2005) and ecological functions. The saltmarsh at the Orange River Mouth has become degraded over time following numerous anthropogenic impacts. As a result the Transboundary RAMSAR site was placed on the Montreux record emphasising the importance for rehabilitation. The potential of the marsh for natural rehabilitation was assessed through three physical factors which were considered to have the most influence on the saltmarsh i.e. 1) sediment 2) water 3) wind. Three sampling areas were chosen to investigate the sediment characteristics of the ORM saltmarsh and the suitability for seed germination and adult survival. Site A was representative of the general marsh area, Site B was thought to have favourable sediment conditions for saltmarsh growth because of the large numbers of seedlings and Site C was prone to inundation by wind blown sediment. The sites were sampled in 2005 (dry conditions) and in 2006 after high rainfall and river flooding. Electrical conductivity (EC) of the sediment throughout the marsh was hypersaline in many instances above the tolerance range for S. pillansii (> 80 mS.cm-1) The freshwater event in 2006 lowered salinity significantly in two of the three sites. Differences in sediment characteristics were also compared for three habitats i.e. driftlines, open sites and under vegetation. Driftlines (C. coronopifolia = 872 seedlings m-2; S. pillansii = 1296 seedlings m-2) and the microhabitat associated with adult plants (C. coronopifolia = 803 seedlings m-2; S. pillansii = 721 seedlings m-2) created favourable conditions for seedling growth, however open unvegetated (C. coronopifolia = 56 seedlings m-2; S. pillansii = 49 seedlings m-2) areas had significantly lower seedling density. Due to the marsh currently being in a desertified state this study aimed to establish whether the remaining vegetation could produce enough seed to revegetate the marsh. Laboratory studies indicated that seeds of both species germinated best in freshwater (0 psu). The germination of S. pillansii seeds was 40 percent at 0 psu compared to 5 percent at 35 psu. After storage under hypersaline conditions (35 psu) C. coronopifolia showed 100 percent seed germination when returned to freshwater whereas storage at 70 psu decreased the viability of S. pillansii seeds. The plants are producing adequate seed that will allow for regrowth and rehabilitation if sediment and groundwater characteristics are suitable for seed germination, seedling growth and adult survival. However the increase in bare areas at the Orange River mouth as a result of salt marsh dieback has increased the available sediment source. The wind blown sediment has covered large areas of the remaining adult salt marsh vegetation, particularly in the northern corner at Site C, causing further die-back.
- Full Text:
- Date Issued: 2007
- Authors: Shaw, Gregory Alan
- Date: 2007
- Subjects: Salt marshes -- Orange River , Rivers -- South Africa -- Environmental aspects , Orange River -- Ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10626 , http://hdl.handle.net/10948/603 , http://hdl.handle.net/10948/d1012010 , Salt marshes -- Orange River , Rivers -- South Africa -- Environmental aspects , Orange River -- Ecology
- Description: The Orange River is an important source of freshwater and like many other wetlands in semi-arid regions, supports various social (Spurgeon, 1998), economic (Spurgeon, 1998; Bornman et al., 2005) and ecological functions. The saltmarsh at the Orange River Mouth has become degraded over time following numerous anthropogenic impacts. As a result the Transboundary RAMSAR site was placed on the Montreux record emphasising the importance for rehabilitation. The potential of the marsh for natural rehabilitation was assessed through three physical factors which were considered to have the most influence on the saltmarsh i.e. 1) sediment 2) water 3) wind. Three sampling areas were chosen to investigate the sediment characteristics of the ORM saltmarsh and the suitability for seed germination and adult survival. Site A was representative of the general marsh area, Site B was thought to have favourable sediment conditions for saltmarsh growth because of the large numbers of seedlings and Site C was prone to inundation by wind blown sediment. The sites were sampled in 2005 (dry conditions) and in 2006 after high rainfall and river flooding. Electrical conductivity (EC) of the sediment throughout the marsh was hypersaline in many instances above the tolerance range for S. pillansii (> 80 mS.cm-1) The freshwater event in 2006 lowered salinity significantly in two of the three sites. Differences in sediment characteristics were also compared for three habitats i.e. driftlines, open sites and under vegetation. Driftlines (C. coronopifolia = 872 seedlings m-2; S. pillansii = 1296 seedlings m-2) and the microhabitat associated with adult plants (C. coronopifolia = 803 seedlings m-2; S. pillansii = 721 seedlings m-2) created favourable conditions for seedling growth, however open unvegetated (C. coronopifolia = 56 seedlings m-2; S. pillansii = 49 seedlings m-2) areas had significantly lower seedling density. Due to the marsh currently being in a desertified state this study aimed to establish whether the remaining vegetation could produce enough seed to revegetate the marsh. Laboratory studies indicated that seeds of both species germinated best in freshwater (0 psu). The germination of S. pillansii seeds was 40 percent at 0 psu compared to 5 percent at 35 psu. After storage under hypersaline conditions (35 psu) C. coronopifolia showed 100 percent seed germination when returned to freshwater whereas storage at 70 psu decreased the viability of S. pillansii seeds. The plants are producing adequate seed that will allow for regrowth and rehabilitation if sediment and groundwater characteristics are suitable for seed germination, seedling growth and adult survival. However the increase in bare areas at the Orange River mouth as a result of salt marsh dieback has increased the available sediment source. The wind blown sediment has covered large areas of the remaining adult salt marsh vegetation, particularly in the northern corner at Site C, causing further die-back.
- Full Text:
- Date Issued: 2007
Report of the multidisciplinary investigation of differentiation and potential hybridisation between two Yellowfish species Labeobarbus Kimberleyensis and L. Aeneus from the Orange-Vaal system
- Bloomer, Paulette, Villet, Martin H, Bills, Ian R, Van der Bank, F Herman, Jones, Nick, Walsh, Gina
- Authors: Bloomer, Paulette , Villet, Martin H , Bills, Ian R , Van der Bank, F Herman , Jones, Nick , Walsh, Gina
- Date: 2007
- Language: English
- Type: Report
- Identifier: vital:7162 , http://hdl.handle.net/10962/d1011937
- Description: From the executive summary]: The relationships within and between two yellowfish species, Labeobarbus aeneus (smallmouth yellowfish) and L. kimberleyensis (largemouth yellowfish) from the Orange-Vaal system were investigated through three independently conducted studies of the same material collected from the Sak River (the type locality of L. aeneus), the upper Orange River at Aliwal North and the lower Orange River at Pella and Onseepkans.
- Full Text:
- Date Issued: 2007
- Authors: Bloomer, Paulette , Villet, Martin H , Bills, Ian R , Van der Bank, F Herman , Jones, Nick , Walsh, Gina
- Date: 2007
- Language: English
- Type: Report
- Identifier: vital:7162 , http://hdl.handle.net/10962/d1011937
- Description: From the executive summary]: The relationships within and between two yellowfish species, Labeobarbus aeneus (smallmouth yellowfish) and L. kimberleyensis (largemouth yellowfish) from the Orange-Vaal system were investigated through three independently conducted studies of the same material collected from the Sak River (the type locality of L. aeneus), the upper Orange River at Aliwal North and the lower Orange River at Pella and Onseepkans.
- Full Text:
- Date Issued: 2007
Reproductive co-existence among five sympatric single-stemmed aloes in the Gamtoos River Valley, Eastern Cape
- Authors: Botes, Christo
- Date: 2007
- Subjects: Aloe -- South Africa -- Gamtoos River Valley , Aloe -- South Africa -- Identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10628 , http://hdl.handle.net/10948/481 , Aloe -- South Africa -- Gamtoos River Valley , Aloe -- South Africa -- Identification
- Description: In this study I documented the convergence of five congeneric bird-pollinated plants (Aloe pluridens, A. lineata var. muirii, A. speciosa, A. africana, and A. ferox) into three functional groups based on size, shape, and the arrangements of flowers on the inflorescence, but also nectar rewards, pollen deposition sites on the bird-pollinators, and the degree to which bees play a role in their pollination. Individuals of similar functional groups were divergent in their peak flowering times and limited their degree of flowering overlap further by spatial aggregation and niche separation, within the Thicket of the Gamtoos River Valley. The nectar properties were especially useful in structuring the bird pollinator community, which resulted in greater ethological isolation and hence, greater reproductive assurance in the mixed co-flowering plant communities. Choice array experiments revealed that it was the fine scale aggregation of flowering individuals that ensured that bird-pollinators feed selectively, since when equal choice was available, interspecific visitation increased significantly compared to natural scenarios. Bird behaviour and the ecological intermediateness of one to the species explained its prominence in hybrid combinations. The spatial occurrence of hybrid individuals can be traced back to the energetics of foraging and its influence on bird floral constancy. The pollination ecology of similar South African Aloe species were extrapolated from these and recent findings by various authors, but emphasises the need for a robust natural phylogeny of the Aloaceae in order to draw comprehensive conclusions on the evolutionary radiation of this highly charismatic group.
- Full Text:
- Date Issued: 2007
- Authors: Botes, Christo
- Date: 2007
- Subjects: Aloe -- South Africa -- Gamtoos River Valley , Aloe -- South Africa -- Identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10628 , http://hdl.handle.net/10948/481 , Aloe -- South Africa -- Gamtoos River Valley , Aloe -- South Africa -- Identification
- Description: In this study I documented the convergence of five congeneric bird-pollinated plants (Aloe pluridens, A. lineata var. muirii, A. speciosa, A. africana, and A. ferox) into three functional groups based on size, shape, and the arrangements of flowers on the inflorescence, but also nectar rewards, pollen deposition sites on the bird-pollinators, and the degree to which bees play a role in their pollination. Individuals of similar functional groups were divergent in their peak flowering times and limited their degree of flowering overlap further by spatial aggregation and niche separation, within the Thicket of the Gamtoos River Valley. The nectar properties were especially useful in structuring the bird pollinator community, which resulted in greater ethological isolation and hence, greater reproductive assurance in the mixed co-flowering plant communities. Choice array experiments revealed that it was the fine scale aggregation of flowering individuals that ensured that bird-pollinators feed selectively, since when equal choice was available, interspecific visitation increased significantly compared to natural scenarios. Bird behaviour and the ecological intermediateness of one to the species explained its prominence in hybrid combinations. The spatial occurrence of hybrid individuals can be traced back to the energetics of foraging and its influence on bird floral constancy. The pollination ecology of similar South African Aloe species were extrapolated from these and recent findings by various authors, but emphasises the need for a robust natural phylogeny of the Aloaceae in order to draw comprehensive conclusions on the evolutionary radiation of this highly charismatic group.
- Full Text:
- Date Issued: 2007
Resistance or tolerance: an examination of aphid (Sitobion yakini) phloem feeding on Betta and Betta-Dn wheat (Triticum aestivum)
- De Wet, L R, Botha, Christiaan E J
- Authors: De Wet, L R , Botha, Christiaan E J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6517 , http://hdl.handle.net/10962/d1005945
- Description: Engineering pest resistance into crops is important. However, the mechanisms of resistance are not clearly understood. In this study, we examined the effects of aphid feeding on Russian wheat aphid-resistant and -susceptible cultivars of wheat (Triticum aestivum L.); Betta-Dn and Betta, respectively, by the grass aphid, Sitobion yakini (Eastop). These cultivars were grown with or without aphid colonies. In each case, we examined the plants specifically for the formation of wound callose associated with the phloem, using aniline blue and fluorescence microscopy. We observed that aphid feeding stimulated the formation of wound callose in the susceptible cultivar, but that callose was comparatively reduced in the resistant cultivar of wheat. In a separate series of experiments, the xenobiotic, 5, 6-carboxyfluorescein diacetate was applied to attached sink leaves, distal to feeding aphids. When leaf segments were examined four hours after application, little evidence of phloem transport of the fluorescent cleavage product, 5, 6-carboxyfluorescein (5, 6-CF), was evident below known aphid-probed sieve tubes. Low levels or absence of 5, 6-CF indicates that either the aphids have successfully redirected sap to themselves, or that the phloem is no longer functional. In contrast, 5, 6-CF transport was evident below sites of aphid probing in Betta-Dn, suggesting that the phloem was still capable of long-distance transport. In addition, callose deposition was reduced in Betta-Dn leaf phloem and it is surmised that transport was not as affected by aphid feeding in the resistant cultivar. This indicates that the ‘resistant’ wheat cultivar may in fact be tolerant to aphid feeding by successfully overcoming the nutrient drain that feeding aphids imposed on the phloem transport system.
- Full Text:
- Date Issued: 2007
- Authors: De Wet, L R , Botha, Christiaan E J
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6517 , http://hdl.handle.net/10962/d1005945
- Description: Engineering pest resistance into crops is important. However, the mechanisms of resistance are not clearly understood. In this study, we examined the effects of aphid feeding on Russian wheat aphid-resistant and -susceptible cultivars of wheat (Triticum aestivum L.); Betta-Dn and Betta, respectively, by the grass aphid, Sitobion yakini (Eastop). These cultivars were grown with or without aphid colonies. In each case, we examined the plants specifically for the formation of wound callose associated with the phloem, using aniline blue and fluorescence microscopy. We observed that aphid feeding stimulated the formation of wound callose in the susceptible cultivar, but that callose was comparatively reduced in the resistant cultivar of wheat. In a separate series of experiments, the xenobiotic, 5, 6-carboxyfluorescein diacetate was applied to attached sink leaves, distal to feeding aphids. When leaf segments were examined four hours after application, little evidence of phloem transport of the fluorescent cleavage product, 5, 6-carboxyfluorescein (5, 6-CF), was evident below known aphid-probed sieve tubes. Low levels or absence of 5, 6-CF indicates that either the aphids have successfully redirected sap to themselves, or that the phloem is no longer functional. In contrast, 5, 6-CF transport was evident below sites of aphid probing in Betta-Dn, suggesting that the phloem was still capable of long-distance transport. In addition, callose deposition was reduced in Betta-Dn leaf phloem and it is surmised that transport was not as affected by aphid feeding in the resistant cultivar. This indicates that the ‘resistant’ wheat cultivar may in fact be tolerant to aphid feeding by successfully overcoming the nutrient drain that feeding aphids imposed on the phloem transport system.
- Full Text:
- Date Issued: 2007
Rhodes University Graduation Ceremony 2007
- Authors: Rhodes University
- Date: 2007
- Language: English
- Type: text
- Identifier: vital:8140 , http://hdl.handle.net/10962/d1007252
- Description: Rhodes University Graduation Ceremonies 1820 Settlers National Monument Thursday, 12 April 2007 at 18:00 [and] Friday, 13 April 2007 at 10:30; 14:30 & 18:00 [and] Saturday, 14 April 2007 at 10:30
- Full Text:
- Date Issued: 2007
- Authors: Rhodes University
- Date: 2007
- Language: English
- Type: text
- Identifier: vital:8140 , http://hdl.handle.net/10962/d1007252
- Description: Rhodes University Graduation Ceremonies 1820 Settlers National Monument Thursday, 12 April 2007 at 18:00 [and] Friday, 13 April 2007 at 10:30; 14:30 & 18:00 [and] Saturday, 14 April 2007 at 10:30
- Full Text:
- Date Issued: 2007
Rhodes University Research Report 2007
- Authors: Rhodes University
- Date: 2007
- Language: English
- Type: Text
- Identifier: vital:562 , http://hdl.handle.net/10962/d1011958
- Description: [From Introduction] For the past 8 years Rhodes University has maintained a research output record (based on publications and Masters and PhD graduates) which has placed it consistently amongst the top three universities in the country on the basis of outputs per capita academic staff member. The past year was no exception. Journal publications were the highest to date (261.9 units) and Masters and PhD graduates (274 units) are amongst the highest achieved, largely due to the record number of PhD graduates (33) in the Science Faculty. In recent years this per capita output has consistently been over 60% higher than the national average. An encouraging aspect of the journal publications in 2007 is the increase in the percentage of articles in subsidy earning journals. While it is appreciated that the most appropriate journals in certain fields of research are not always those that are on the Department of Education’s approved lists, it is financially critical to the University’s research effort and the University as a whole that subsidy earning outputs are maximised. Another positive outcome of the most recent audit of Rhodes’s research outputs (2006; 2007 data will only be available at the end of 2008) is that 89% of the publications in the form of books, chapters and conference proceedings submitted to the Department of Education were approved for subsidy. This is a significantly higher percentage approval than in the past. The award of two highly prestigious NRF/DST Research Chairs to Profs Tebello Nyokong and Christopher McQuaid as part of the first round of the SA Research Chairs Initiative was another major achievement. These Chairs will significantly enhance the research profile and productivity of the University as will the recent award of the highly prestigious Centre of Excellence in Nanotechnology to be headed by Prof Nyokong. Only three such centres of excellence have been established and were officially launched by the Minister of Science and Technology in November 2007. The Centre will be host to researchers from throughout South Africa and will focus on novel technologies for cancer treatment and the development of new biosensors for disease treatment and water contamination. An encouraging statistic recently released by the National Research Foundation indicates that Rhodes has the fourth highest percentage (15.4%) of rated researchers in the country which is an excellent achievement. NRF ratings are awarded to researchers in all disciplines who are regarded as national and international leaders in their fields. Amongst these researchers, three were also recognised by the University and were awarded the Vice-Chancellor’s Research Awards (see highlights section). Postgraduate students have once again been the cornerstone of much of the research activities in all Faculties and have contributed significantly to the research outputs of the University both as co-authors on publications and through the good graduation rates of Masters and PhD candidates. This is particularly evident for example in the Science Faculty, in which Masters and Doctoral students contributed to over 90% of the Faculty and 60% of the University’s outputs. A key factor in the high profile and success of postgraduates at Rhodes is the excellent supervision they receive and all supervisors are to be congratulated for their dedicated approach to what has become an increasingly onerous academic responsibility. They and the Research Office have benefited enormously from the very able support of the Postgraduate Liaison Committee chaired for a second year by Dan Parker. The work of this committee is highly valued. Finally, this will be my last contribution to the annual Rhodes Research Reports as I will be retiring at the end of 2008. I would like to wish my successor with responsibility for Research at Rhodes, the new DVC: R&D Dr Peter Clayton, every success in the future which I am confident will see research at the University going from strength to strength. I would also like to take the opportunity to express my sincere and grateful thanks to all those who have supported me and contributed to the success of Rhodes research in my past 10 years as Dean of Research. This includes two Vice-Chancellors, members of Senior Management, Deans, Heads of Department and staff and postgraduate students in both academic departments and administrative divisions. In particular, a very big thank you to all the staff who have worked in the Research Office and have made such a significant contribution over this past decade. Special mention must be made of my first Assistant, Moira Pogrund, who was instrumental in the establishment and success of the Research Office from its inception in 1998. She gave true meaning to the word efficiency and her outstanding contribution is being continued by the excellent work of her successor, Dr Heather Davies-Coleman. John Gillam has been a tower of strength in the management and administration of postgraduate financial aid and has been an invaluable advisor and confidant to countless postgraduate students over this period.
- Full Text:
- Date Issued: 2007
- Authors: Rhodes University
- Date: 2007
- Language: English
- Type: Text
- Identifier: vital:562 , http://hdl.handle.net/10962/d1011958
- Description: [From Introduction] For the past 8 years Rhodes University has maintained a research output record (based on publications and Masters and PhD graduates) which has placed it consistently amongst the top three universities in the country on the basis of outputs per capita academic staff member. The past year was no exception. Journal publications were the highest to date (261.9 units) and Masters and PhD graduates (274 units) are amongst the highest achieved, largely due to the record number of PhD graduates (33) in the Science Faculty. In recent years this per capita output has consistently been over 60% higher than the national average. An encouraging aspect of the journal publications in 2007 is the increase in the percentage of articles in subsidy earning journals. While it is appreciated that the most appropriate journals in certain fields of research are not always those that are on the Department of Education’s approved lists, it is financially critical to the University’s research effort and the University as a whole that subsidy earning outputs are maximised. Another positive outcome of the most recent audit of Rhodes’s research outputs (2006; 2007 data will only be available at the end of 2008) is that 89% of the publications in the form of books, chapters and conference proceedings submitted to the Department of Education were approved for subsidy. This is a significantly higher percentage approval than in the past. The award of two highly prestigious NRF/DST Research Chairs to Profs Tebello Nyokong and Christopher McQuaid as part of the first round of the SA Research Chairs Initiative was another major achievement. These Chairs will significantly enhance the research profile and productivity of the University as will the recent award of the highly prestigious Centre of Excellence in Nanotechnology to be headed by Prof Nyokong. Only three such centres of excellence have been established and were officially launched by the Minister of Science and Technology in November 2007. The Centre will be host to researchers from throughout South Africa and will focus on novel technologies for cancer treatment and the development of new biosensors for disease treatment and water contamination. An encouraging statistic recently released by the National Research Foundation indicates that Rhodes has the fourth highest percentage (15.4%) of rated researchers in the country which is an excellent achievement. NRF ratings are awarded to researchers in all disciplines who are regarded as national and international leaders in their fields. Amongst these researchers, three were also recognised by the University and were awarded the Vice-Chancellor’s Research Awards (see highlights section). Postgraduate students have once again been the cornerstone of much of the research activities in all Faculties and have contributed significantly to the research outputs of the University both as co-authors on publications and through the good graduation rates of Masters and PhD candidates. This is particularly evident for example in the Science Faculty, in which Masters and Doctoral students contributed to over 90% of the Faculty and 60% of the University’s outputs. A key factor in the high profile and success of postgraduates at Rhodes is the excellent supervision they receive and all supervisors are to be congratulated for their dedicated approach to what has become an increasingly onerous academic responsibility. They and the Research Office have benefited enormously from the very able support of the Postgraduate Liaison Committee chaired for a second year by Dan Parker. The work of this committee is highly valued. Finally, this will be my last contribution to the annual Rhodes Research Reports as I will be retiring at the end of 2008. I would like to wish my successor with responsibility for Research at Rhodes, the new DVC: R&D Dr Peter Clayton, every success in the future which I am confident will see research at the University going from strength to strength. I would also like to take the opportunity to express my sincere and grateful thanks to all those who have supported me and contributed to the success of Rhodes research in my past 10 years as Dean of Research. This includes two Vice-Chancellors, members of Senior Management, Deans, Heads of Department and staff and postgraduate students in both academic departments and administrative divisions. In particular, a very big thank you to all the staff who have worked in the Research Office and have made such a significant contribution over this past decade. Special mention must be made of my first Assistant, Moira Pogrund, who was instrumental in the establishment and success of the Research Office from its inception in 1998. She gave true meaning to the word efficiency and her outstanding contribution is being continued by the excellent work of her successor, Dr Heather Davies-Coleman. John Gillam has been a tower of strength in the management and administration of postgraduate financial aid and has been an invaluable advisor and confidant to countless postgraduate students over this period.
- Full Text:
- Date Issued: 2007
Selecting stories to tell: the gatekeeping of international news at SAfm
- Authors: Ticha, Abel Akara
- Date: 2007
- Subjects: South African Broadcasting Corporation SAfm (South Africa) Radio broadcasting -- South Africa Foreign news -- South Africa Radio journalism -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3499 , http://hdl.handle.net/10962/d1004520
- Description: The premise of this thesis is that the selection of international news to be aired on the bulletins of SAfm by SABC Radio News staff is influenced by more complex factors than could be seen solely from the prism of an empirical journalistic paradigm. Drawing from data obtained through participant observation and interviewing, it is noted that there has been a revolution from a propagandist approach during apartheid to a professional approach following the demise of apartheid, in the selection of international news for bulletins on SAfm. Using Lewin's theory of forces in decision making and locating it within four out of five levels of a framework of gatekeeping analysis provided by Shoemaker (1991) and Shoemaker et al (200 I), it is concluded that the delimiting well-tested routines of newsmaking act as powerful companions of individuals' selection decisions of international news broadcast on SAfm's bulletins. However, these routines are adapted to meet the organisational demands of the SABC, which as a Public Service Broadcaster (PBS) has embraced the discourse of South African nationalism/panAfricanism, as a major philosophy underpinning the Corporation's coverage of the world. Therefore, some individual, routine and organisational factors influencing the se lection of international news broadcast on SAfm's bulletins, are predetermined and co-determined by the social system (the ideological/discursive structure), which is promoted by certain social institutions. Instances of spokespersons of such institutions as governments, international governmental and non-governmental organisations, etc., officiating the news abound; the gatekeepers use them to meet routine professional standards of journalism. This potentially works to sustain the hegemonic discourses of the powerful in international affairs (in tenns of core/peripheral nations relations, and elite classlruled majority relations) though there is a conscious oppositional effort to modify or dwarf stories that explicitly promote imperialism and to hold rulers accountable to the public. It is posited that the time is ripe for newsworkers responsible for the production of bulletins for SAfm to take the risk that may be necessary to inject a few changes in routine practices that could limit the engineering of consent to the powerful elites in the international arena.
- Full Text:
- Date Issued: 2007
- Authors: Ticha, Abel Akara
- Date: 2007
- Subjects: South African Broadcasting Corporation SAfm (South Africa) Radio broadcasting -- South Africa Foreign news -- South Africa Radio journalism -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3499 , http://hdl.handle.net/10962/d1004520
- Description: The premise of this thesis is that the selection of international news to be aired on the bulletins of SAfm by SABC Radio News staff is influenced by more complex factors than could be seen solely from the prism of an empirical journalistic paradigm. Drawing from data obtained through participant observation and interviewing, it is noted that there has been a revolution from a propagandist approach during apartheid to a professional approach following the demise of apartheid, in the selection of international news for bulletins on SAfm. Using Lewin's theory of forces in decision making and locating it within four out of five levels of a framework of gatekeeping analysis provided by Shoemaker (1991) and Shoemaker et al (200 I), it is concluded that the delimiting well-tested routines of newsmaking act as powerful companions of individuals' selection decisions of international news broadcast on SAfm's bulletins. However, these routines are adapted to meet the organisational demands of the SABC, which as a Public Service Broadcaster (PBS) has embraced the discourse of South African nationalism/panAfricanism, as a major philosophy underpinning the Corporation's coverage of the world. Therefore, some individual, routine and organisational factors influencing the se lection of international news broadcast on SAfm's bulletins, are predetermined and co-determined by the social system (the ideological/discursive structure), which is promoted by certain social institutions. Instances of spokespersons of such institutions as governments, international governmental and non-governmental organisations, etc., officiating the news abound; the gatekeepers use them to meet routine professional standards of journalism. This potentially works to sustain the hegemonic discourses of the powerful in international affairs (in tenns of core/peripheral nations relations, and elite classlruled majority relations) though there is a conscious oppositional effort to modify or dwarf stories that explicitly promote imperialism and to hold rulers accountable to the public. It is posited that the time is ripe for newsworkers responsible for the production of bulletins for SAfm to take the risk that may be necessary to inject a few changes in routine practices that could limit the engineering of consent to the powerful elites in the international arena.
- Full Text:
- Date Issued: 2007
Severe convective storm risk in the Eastern Cape Province of South Africa
- Authors: Pyle, Desmond Mark
- Date: 2007
- Subjects: Storms -- South Africa -- Eastern Cape Natural disasters -- South Africa -- Eastern Cape Disasters -- South Africa -- Eastern Cape Disaster relief -- South Africa -- Eastern Cape -- Management Meteorology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4853 , http://hdl.handle.net/10962/d1005529
- Description: This study investigates the temporal, spatial and impact characteristics of severe convective storm hazard and risk in the Eastern Cape Province of South Africa. Using historical data on severe convective storms dating from 1897, patterns of the hazard threat and risk to various geographic populations were investigated. A conceptual framework that emphasises the combined role hazard and vulnerability play in defining risk was used for the study. A methodology for ranking the severity of the storms in the historical dataset, based on recorded damage/impact, was specifically developed for the study. It is intended that this methodology will have a potentially wider application and may be adapted to a range of hazard impact and risk studies in South Africa and internationally. The study was undertaken within the context of the South African Disaster Management Act of 2002. Findings of the study show that severe convective storms can occur throughout the province, but there are clearly demarcated areas of higher frequency and concentration. The impact of storms is particularly severe on impoverished and vulnerable rural populations in the eastern parts of the province, where there is an urgent need for building capacity in disaster risk management. A major outcome of the study is the production of a severe convective storm hazard/risk map of the Eastern Cape, which it is hoped will be of benefit to a number of stakeholders in the province, particularly disaster management, but also the South African Weather Service, agricultural organisations, development/planning authorities, educational authorities and risk insurers. It is hoped that this map and the study in general will assist in guiding the operational responses of the various authorities, especially in terms of those interventions aimed at disaster risk reduction in the Eastern Cape.
- Full Text:
- Date Issued: 2007
- Authors: Pyle, Desmond Mark
- Date: 2007
- Subjects: Storms -- South Africa -- Eastern Cape Natural disasters -- South Africa -- Eastern Cape Disasters -- South Africa -- Eastern Cape Disaster relief -- South Africa -- Eastern Cape -- Management Meteorology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4853 , http://hdl.handle.net/10962/d1005529
- Description: This study investigates the temporal, spatial and impact characteristics of severe convective storm hazard and risk in the Eastern Cape Province of South Africa. Using historical data on severe convective storms dating from 1897, patterns of the hazard threat and risk to various geographic populations were investigated. A conceptual framework that emphasises the combined role hazard and vulnerability play in defining risk was used for the study. A methodology for ranking the severity of the storms in the historical dataset, based on recorded damage/impact, was specifically developed for the study. It is intended that this methodology will have a potentially wider application and may be adapted to a range of hazard impact and risk studies in South Africa and internationally. The study was undertaken within the context of the South African Disaster Management Act of 2002. Findings of the study show that severe convective storms can occur throughout the province, but there are clearly demarcated areas of higher frequency and concentration. The impact of storms is particularly severe on impoverished and vulnerable rural populations in the eastern parts of the province, where there is an urgent need for building capacity in disaster risk management. A major outcome of the study is the production of a severe convective storm hazard/risk map of the Eastern Cape, which it is hoped will be of benefit to a number of stakeholders in the province, particularly disaster management, but also the South African Weather Service, agricultural organisations, development/planning authorities, educational authorities and risk insurers. It is hoped that this map and the study in general will assist in guiding the operational responses of the various authorities, especially in terms of those interventions aimed at disaster risk reduction in the Eastern Cape.
- Full Text:
- Date Issued: 2007
Social learning processes in a citrus farming community of practice
- Authors: Downsborough, Linda
- Date: 2007
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1878 , http://hdl.handle.net/10962/d1005859
- Description: Learning takes place in a number of ways. Situated learning for example, tries to shift the focus from the individual as a learner to the learner participating in the social world and from learning as a strictly cognitive process to a more encompassing view of social practice. The overall aim of this research was to gain a deeper understanding of the ways in which learning takes place in and between members of a citrus farming community, in other words it was to investigate the social learning processes. The research was undertaken in Patensie, a citrus farming community of the Gamtoos River Valley, Eastern Cape, South Africa. Data was generated through the use of interviews and informal discussions with participants together with document analysis, such as minutes of meetings. I also made observations of the learning interactions that were evident and also the interactions that were evident in the area as a whole. The data was analysed in two phases, the first involved reading across the interview transcripts and organizing the data under broad themes while the second phase made use of an analytical framework, a Community of Practice perspective to further analyze and engage with the data. I drew quite strongly on the ideas of situated learning, Communities of Practice and the notion of Legitimate Peripheral Participation (Lave & Wenger, 1991) as a means to understand, interpret and describe the social learning processes. The research highlighted that in this case study, citrus farmers learn in a number of sociological ways, for example through intergenerational learning (in the family), learning from each other in a Community of Practice, learning from private consultants and extensions officers as well as from other organizations and institutions. It also considered how farmers' learning had influenced land use practice in the area. This brought to the fore an emerging partnership with a conservation agent based on providing economic incentives to farmers to engage in sustainable landuse practices. It is hoped that this research may inform future educational endeavours by shedding light on the social learning processes and by drawing attention to key aspects of learning that may previously have been overlooked in research.
- Full Text:
- Date Issued: 2007
- Authors: Downsborough, Linda
- Date: 2007
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1878 , http://hdl.handle.net/10962/d1005859
- Description: Learning takes place in a number of ways. Situated learning for example, tries to shift the focus from the individual as a learner to the learner participating in the social world and from learning as a strictly cognitive process to a more encompassing view of social practice. The overall aim of this research was to gain a deeper understanding of the ways in which learning takes place in and between members of a citrus farming community, in other words it was to investigate the social learning processes. The research was undertaken in Patensie, a citrus farming community of the Gamtoos River Valley, Eastern Cape, South Africa. Data was generated through the use of interviews and informal discussions with participants together with document analysis, such as minutes of meetings. I also made observations of the learning interactions that were evident and also the interactions that were evident in the area as a whole. The data was analysed in two phases, the first involved reading across the interview transcripts and organizing the data under broad themes while the second phase made use of an analytical framework, a Community of Practice perspective to further analyze and engage with the data. I drew quite strongly on the ideas of situated learning, Communities of Practice and the notion of Legitimate Peripheral Participation (Lave & Wenger, 1991) as a means to understand, interpret and describe the social learning processes. The research highlighted that in this case study, citrus farmers learn in a number of sociological ways, for example through intergenerational learning (in the family), learning from each other in a Community of Practice, learning from private consultants and extensions officers as well as from other organizations and institutions. It also considered how farmers' learning had influenced land use practice in the area. This brought to the fore an emerging partnership with a conservation agent based on providing economic incentives to farmers to engage in sustainable landuse practices. It is hoped that this research may inform future educational endeavours by shedding light on the social learning processes and by drawing attention to key aspects of learning that may previously have been overlooked in research.
- Full Text:
- Date Issued: 2007
Statistical analyses of artificial waterpoints: their effect on the herbaceous and woody structure composition within the Kruger National Park
- Authors: Goodall, Victoria Lucy
- Date: 2007
- Subjects: South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5570 , http://hdl.handle.net/10962/d1002810 , South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Description: The objective of this project is to link the statistical theory used in the ecological sciences with an actual project that was developed for the South African National Parks Scientific Services. It investigates the changes that have occurred in the herbaceous and woody structure due to the closure of artificial waterpoints; including the impacts that elephants and other herbivores have on the vegetation of the Kruger National Park. This project was designed in conjunction with South African National Parks (SANP) Scientific Services and it is a registered project with this department. The results of this project will be submitted to Scientific Services in accordance with the terms and conditions of a SANP research project. A major concern within the KNP is the declining numbers of rare antelope and numerous projects have been developed to investigate possible ways of halting this decline and thus protecting the heterogeneity of the Kruger National Park. Three different datasets were investigated, covering three aspects of vegetation structure and composition within the KNP. The first investigated the changes that have occurred since the N'washitsumbe enclosure in the Far Northern KNP was fenced off from the rest of the park. The results show that over the 40 years since the enclosure was built, changes have occurred which have resulted in a significant difference in the abundance of Increaser 2 and Decreaser grass species between the inside and the outside of the enclosure. Increaser 2 and Decreaser categories are the result of a grass species classification depending on whether the species thrives or is depressed by heavy grazing. The difference in grass species composition and structure between the inside and the outside of the enclosure indicates that the grazing animals within the KNP have influenced the grass composition in a way that favours the dominant animals. This has resulted in a declining roan antelope population - one of the species that is considered as a 'rare antelope'. Many artificial waterpoints (boreholes and dams) have also been closed throughout the KNP in the hope of resulting in a change in vegetation structure and composition in favour of the roan. Veld condition assessment data for 87 boreholes throughout the Park was analyzed to determine whether the veld in the vicinity is beginning to change towards a more Decreaser dominated sward which would favour the roan. The results were analyzed for the different regions of the Park; and they indicate that changes are becoming evident; however, the results are not particularly conclusive, yet. The majority of the boreholes were closed between 1994 and 1998 which means that not a lot of data were available to be analyzed. A similar study conducted in another 10 years time might reveal more meaningful results. However the results are moving in the direction hoped for by the management of the KNP. The results show that the grass composition has a higher proportion of Decreaser grasses since the closure of the waterpoints, and the grass biomass around these areas has also improved. The results were analyzed on an individual basis; and then on a regional basis as the minimal data meant that the individual analyses did not provide any significant results. A third study was then done on the impact that the rapidly increasing elephant population on the vegetation within the Riparian zone along three rivers in the Far Northern region of the KNP. The riparian zone is an important part of the landscape, in terms of providing food for many animals as well as shade. The elephant population has increased substantially since the termination of the culling program and this means that the feeding requirements of the population has increased which could result in severe damage upon the vegetation, as elephants can be very destructive feeders. The results show surprising differences between the three years of data that were analyzed; however the results indicate that the elephants are targeting specific height ranges of trees when feeding; however they do not seem to consistently target specific tree species. This is positive for the diversity of the Riparian zone as this region is very important both ecologically and aesthetically for the tourists who visit the Park.
- Full Text:
- Date Issued: 2007
- Authors: Goodall, Victoria Lucy
- Date: 2007
- Subjects: South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5570 , http://hdl.handle.net/10962/d1002810 , South African National Parks , Ecology -- Statistical methods , Regression analysis , Log-linear models , Game reserves -- South Africa , Kruger National Park (South Africa)
- Description: The objective of this project is to link the statistical theory used in the ecological sciences with an actual project that was developed for the South African National Parks Scientific Services. It investigates the changes that have occurred in the herbaceous and woody structure due to the closure of artificial waterpoints; including the impacts that elephants and other herbivores have on the vegetation of the Kruger National Park. This project was designed in conjunction with South African National Parks (SANP) Scientific Services and it is a registered project with this department. The results of this project will be submitted to Scientific Services in accordance with the terms and conditions of a SANP research project. A major concern within the KNP is the declining numbers of rare antelope and numerous projects have been developed to investigate possible ways of halting this decline and thus protecting the heterogeneity of the Kruger National Park. Three different datasets were investigated, covering three aspects of vegetation structure and composition within the KNP. The first investigated the changes that have occurred since the N'washitsumbe enclosure in the Far Northern KNP was fenced off from the rest of the park. The results show that over the 40 years since the enclosure was built, changes have occurred which have resulted in a significant difference in the abundance of Increaser 2 and Decreaser grass species between the inside and the outside of the enclosure. Increaser 2 and Decreaser categories are the result of a grass species classification depending on whether the species thrives or is depressed by heavy grazing. The difference in grass species composition and structure between the inside and the outside of the enclosure indicates that the grazing animals within the KNP have influenced the grass composition in a way that favours the dominant animals. This has resulted in a declining roan antelope population - one of the species that is considered as a 'rare antelope'. Many artificial waterpoints (boreholes and dams) have also been closed throughout the KNP in the hope of resulting in a change in vegetation structure and composition in favour of the roan. Veld condition assessment data for 87 boreholes throughout the Park was analyzed to determine whether the veld in the vicinity is beginning to change towards a more Decreaser dominated sward which would favour the roan. The results were analyzed for the different regions of the Park; and they indicate that changes are becoming evident; however, the results are not particularly conclusive, yet. The majority of the boreholes were closed between 1994 and 1998 which means that not a lot of data were available to be analyzed. A similar study conducted in another 10 years time might reveal more meaningful results. However the results are moving in the direction hoped for by the management of the KNP. The results show that the grass composition has a higher proportion of Decreaser grasses since the closure of the waterpoints, and the grass biomass around these areas has also improved. The results were analyzed on an individual basis; and then on a regional basis as the minimal data meant that the individual analyses did not provide any significant results. A third study was then done on the impact that the rapidly increasing elephant population on the vegetation within the Riparian zone along three rivers in the Far Northern region of the KNP. The riparian zone is an important part of the landscape, in terms of providing food for many animals as well as shade. The elephant population has increased substantially since the termination of the culling program and this means that the feeding requirements of the population has increased which could result in severe damage upon the vegetation, as elephants can be very destructive feeders. The results show surprising differences between the three years of data that were analyzed; however the results indicate that the elephants are targeting specific height ranges of trees when feeding; however they do not seem to consistently target specific tree species. This is positive for the diversity of the Riparian zone as this region is very important both ecologically and aesthetically for the tourists who visit the Park.
- Full Text:
- Date Issued: 2007
Study of titanium, tantalum and chromium catalysts for use in industrial transformations
- Authors: Tau, Prudence Lerato
- Date: 2007
- Subjects: Titanium Tantalum Phthalocyanines Electrochemistry Photochemotherapy Chromium Spectrum analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4363 , http://hdl.handle.net/10962/d1005028
- Description: PART A The syntheses, spectroscopic and electrochemical characterisation of a series of titanium and tantalum phthalocyanine complexes are reported. The complexes are unsubstituted and substituted at either the peripheral or non-peripheral positions with sulphonates, aryloxy, arylthio or amino groups. The complexes mostly exhibit Qbands in the near-infrared region as well as interesting properties in different solvents. The interaction of differently sulphonated titanium and tantalum phthalocyanine complexes with methyl viologen (MV[superscript 2+]), and hence the stoichiometry and association constants are evaluated. Detailed photophysicochemical properties of the complexes were investigated and are for the first time presented with fluorescence lifetimes easily obtained from fluorescence quenching studies. The transformation of 1-hexene photocatalysed by aryloxy- and arylthio-appended complexes is also presented for the first time. The electrochemical properties of the complexes are unknown and are thus presented. Cyclic (CV) and square wave (SWV) voltammetries, chronocoulometry and spectroelectrochemistry are employed in the study of the complexes. Two oneelectron reductions and a simultaneous 4-electron reduction are observed for the unsubstituted Cl[subscript 3]TaPc. Reduction occurs first at the metal followed by ring-based processes. The tetra- and octa-substituted derivatives however exhibit peculiar electrochemical behaviour where a multi-electron transfer process occurs for complexes bearing certain substituents. For all complexes, the first two reductions are metal-based followed by ring-based processes. A comparative study of the electrocatalytic activities of the complexes towards the oxidation of nitrite is also investigated. The complexes are immobilised onto a glassy carbon electrode either by drop-dry or electropolymerisation methods. All the modified electrodes exhibit improved electrocatalytic oxidation of nitrite than the unmodified electrodes by a twoelectron mechanism producing nitrate ions. Catalytic currents are enhanced and nitrite overpotential reduced to ~ 0.60 V. Kinetic parameters are determined for all complexes and a mechanism is proposed. PART B: The syntheses and electrochemical characterisation of chromium and titanium complexes for the selective trimerisation of ethylene to 1-hexene are presented. The synthesis of the chromium complex requires simple steps while tedious steps are used for the air-sensitive titanium complex. The spectroscopic interaction of the chromium complex with the co-catalyst methylaluminoxane is investigated. The complexes are characterised by electrochemical methods such as cyclic voltammetry and spectroelectrochemistry.
- Full Text:
- Date Issued: 2007
- Authors: Tau, Prudence Lerato
- Date: 2007
- Subjects: Titanium Tantalum Phthalocyanines Electrochemistry Photochemotherapy Chromium Spectrum analysis
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4363 , http://hdl.handle.net/10962/d1005028
- Description: PART A The syntheses, spectroscopic and electrochemical characterisation of a series of titanium and tantalum phthalocyanine complexes are reported. The complexes are unsubstituted and substituted at either the peripheral or non-peripheral positions with sulphonates, aryloxy, arylthio or amino groups. The complexes mostly exhibit Qbands in the near-infrared region as well as interesting properties in different solvents. The interaction of differently sulphonated titanium and tantalum phthalocyanine complexes with methyl viologen (MV[superscript 2+]), and hence the stoichiometry and association constants are evaluated. Detailed photophysicochemical properties of the complexes were investigated and are for the first time presented with fluorescence lifetimes easily obtained from fluorescence quenching studies. The transformation of 1-hexene photocatalysed by aryloxy- and arylthio-appended complexes is also presented for the first time. The electrochemical properties of the complexes are unknown and are thus presented. Cyclic (CV) and square wave (SWV) voltammetries, chronocoulometry and spectroelectrochemistry are employed in the study of the complexes. Two oneelectron reductions and a simultaneous 4-electron reduction are observed for the unsubstituted Cl[subscript 3]TaPc. Reduction occurs first at the metal followed by ring-based processes. The tetra- and octa-substituted derivatives however exhibit peculiar electrochemical behaviour where a multi-electron transfer process occurs for complexes bearing certain substituents. For all complexes, the first two reductions are metal-based followed by ring-based processes. A comparative study of the electrocatalytic activities of the complexes towards the oxidation of nitrite is also investigated. The complexes are immobilised onto a glassy carbon electrode either by drop-dry or electropolymerisation methods. All the modified electrodes exhibit improved electrocatalytic oxidation of nitrite than the unmodified electrodes by a twoelectron mechanism producing nitrate ions. Catalytic currents are enhanced and nitrite overpotential reduced to ~ 0.60 V. Kinetic parameters are determined for all complexes and a mechanism is proposed. PART B: The syntheses and electrochemical characterisation of chromium and titanium complexes for the selective trimerisation of ethylene to 1-hexene are presented. The synthesis of the chromium complex requires simple steps while tedious steps are used for the air-sensitive titanium complex. The spectroscopic interaction of the chromium complex with the co-catalyst methylaluminoxane is investigated. The complexes are characterised by electrochemical methods such as cyclic voltammetry and spectroelectrochemistry.
- Full Text:
- Date Issued: 2007
Study South Africa
- International Education Association of South Africa (IEASA), Higher Education South Africa (Organization), Kishun, Roshen
- Authors: International Education Association of South Africa (IEASA) , Higher Education South Africa (Organization) , Kishun, Roshen
- Date: 2007
- Subjects: Education, Higher -- South Africa , Universities and colleges -- South Africa , Technical Institutes -- South Africa , Vocational guidance -- South Africa
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/65090 , vital:28685 , ISBN 9780620391634
- Description: [Extract from message from Minister of Higher Education, Hon. Naledi Pandor]: It gives me great pleasure to endorse the 7th edition of Study South Africa. The International Education Association of South Africa (IEASA) has once again produced a publication that provides valuable insights and information about South African public universities and their place in the global higher education arena I welcome this publication and congratulate IEASA for its hard work in promoting our higher education institutions internationally. Study South Africa gives a comprehensive picture of higher education in our country. At a glance, the enquirer is able to see all that South African higher education has to offer diversity in terms of institutions, the wide range of affordable courses on offer, the international acceptability of South African qualifications as well as the rich multi-cultural experiences of our campuses. In short, the Guide provides a summary of everything that will assist the potential student to actualise his or her full potential. South African higher education is founded on broad social values such as respect for human life and dignity, commitment to equality and human rights, respect for diversity and nonsexism. Our education system seeks to construct citizens who are conscious of these values and therefore aware of their responsibilities in life and in the lives of others. These values are reflected in the diverse offerings by institutions covered in the Guide. In addition, we have specific mechanisms in place to facilitate internationalisation, and our immigration policies have been relaxed to make it easier for international students, academics and other higher education staff to enter the country and stay for the duration of their planned activity. We also subsidise students from the continent in terms of our policy on the state subsidisation of foreign students at higher education institutions. South Africa shares the global concern about the digital and information divide. We are of the view that access to information is empowering and would therefore like to see as many citizens of our country and the continent connected with the rest of the world, both digitally and in terms of knowledge. By staying in touch with the rest of the world through information sharing and exchange programmes, we minimise this information gap. It is for this reason, therefore, that the work of IEASA in the form of this publication is applauded, because it seeks to promote such exchanges and information sharing. There is no question that through internationalisation we can impact on our political, economic, cultural and social transformation. We can also address our skills shortage, build research capacity, enrich curricula and enhance the student experience. Collectively higher education institutions in South Africa offer an impressive array of information and communication technologies, well stocked and interconnected libraries and some scholars who are among the best in the world, making the country a destination of choice for both Africans and students from abroad. We aspire to make all our international partners, students and staff feel at home and content with what our institutions offer them, pleasant living and study or work environments. We want them to be proud of their association with South African higher education and be ambassadors for the system once they leave South Africa. , 7th Edition
- Full Text:
- Date Issued: 2007
- Authors: International Education Association of South Africa (IEASA) , Higher Education South Africa (Organization) , Kishun, Roshen
- Date: 2007
- Subjects: Education, Higher -- South Africa , Universities and colleges -- South Africa , Technical Institutes -- South Africa , Vocational guidance -- South Africa
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/65090 , vital:28685 , ISBN 9780620391634
- Description: [Extract from message from Minister of Higher Education, Hon. Naledi Pandor]: It gives me great pleasure to endorse the 7th edition of Study South Africa. The International Education Association of South Africa (IEASA) has once again produced a publication that provides valuable insights and information about South African public universities and their place in the global higher education arena I welcome this publication and congratulate IEASA for its hard work in promoting our higher education institutions internationally. Study South Africa gives a comprehensive picture of higher education in our country. At a glance, the enquirer is able to see all that South African higher education has to offer diversity in terms of institutions, the wide range of affordable courses on offer, the international acceptability of South African qualifications as well as the rich multi-cultural experiences of our campuses. In short, the Guide provides a summary of everything that will assist the potential student to actualise his or her full potential. South African higher education is founded on broad social values such as respect for human life and dignity, commitment to equality and human rights, respect for diversity and nonsexism. Our education system seeks to construct citizens who are conscious of these values and therefore aware of their responsibilities in life and in the lives of others. These values are reflected in the diverse offerings by institutions covered in the Guide. In addition, we have specific mechanisms in place to facilitate internationalisation, and our immigration policies have been relaxed to make it easier for international students, academics and other higher education staff to enter the country and stay for the duration of their planned activity. We also subsidise students from the continent in terms of our policy on the state subsidisation of foreign students at higher education institutions. South Africa shares the global concern about the digital and information divide. We are of the view that access to information is empowering and would therefore like to see as many citizens of our country and the continent connected with the rest of the world, both digitally and in terms of knowledge. By staying in touch with the rest of the world through information sharing and exchange programmes, we minimise this information gap. It is for this reason, therefore, that the work of IEASA in the form of this publication is applauded, because it seeks to promote such exchanges and information sharing. There is no question that through internationalisation we can impact on our political, economic, cultural and social transformation. We can also address our skills shortage, build research capacity, enrich curricula and enhance the student experience. Collectively higher education institutions in South Africa offer an impressive array of information and communication technologies, well stocked and interconnected libraries and some scholars who are among the best in the world, making the country a destination of choice for both Africans and students from abroad. We aspire to make all our international partners, students and staff feel at home and content with what our institutions offer them, pleasant living and study or work environments. We want them to be proud of their association with South African higher education and be ambassadors for the system once they leave South Africa. , 7th Edition
- Full Text:
- Date Issued: 2007
The coping resources and subjective well-being of dual-career Hindu mothers
- Authors: Prag, Hanita T
- Date: 2007
- Subjects: Women -- India , Women -- Employment -- India , Hindu women -- Social life and customs
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9932 , http://hdl.handle.net/10948/593 , Women -- India , Women -- Employment -- India , Hindu women -- Social life and customs
- Description: With the increasing number of women entering the labour force internationally, the role of women is changing. Consequently, researchers are pressed to investigate how females of all cultures balance their work and family responsibilities. Amongst Hindu couples, this issue can either be a source of tension or positive support. An overview of literature indicates that the psychological aspects of dual-career Hindu women have received little attention in South Africa. The current study aimed to explore and describe coping resources and the subjective well-being of full-time employed Hindu mothers. The study took the form of a non-experimental exploratory-descriptive design. Participants were selected through nonprobability convenience sampling. The sample of the study consisted of sixty full-time employed Hindu mothers between the ages of 25 and 45 years of age who had at least one dependent primary school child aged between 7 to 12 years. Various questionnaires were used to collect data for this study. These included a Biographical Questionnaire, The Coping Resources Inventory (CRI), The Satisfaction with Life Scale (SWLS), and The Affectometer 2 (AFM2). Data was analysed by means of descriptive statistics. Cronbach’s coefficient alphas were utilised to calculate the reliability of the scores of each questionnaire. A multivariate technique was used to determine the amount of clusters formed. A non-hierarchical partitioning technique known as K-means cluster analysis was utilised in this study. An analysis of variance (ANOVA) was utilised in order to compare the mean scores of the various clusters. A post-hoc analysis using the Scheffé test was computed to test for significant differences. Cohen’s d statistics was subsequently used to determine the practical significance of the differences found between the cluster means on each of the measures. The cluster analysis indicated three clusters that differed significantly from one another on all three measures. The results of the CRI indicated that the participants used cognitive and spiritual resources to assist them to cope with the transition from traditional to modern contemporary roles. It was also found that the participants with low coping resources had inferior subjective well-being compared to those who had average and high CRI scores. The findings indicated that the participants were generally satisfied with their lives and experienced high levels of positive affect and low levels of negative affect. However, as a group there was a trend for the participants to have experienced slightly lower levels of global happiness or slightly negative affect. The results of this study broadens the knowledge base of positive psychology with respect to the diverse cultures and gender roles within South Africa. Overall, this study highlighted the value and the need for South African research on the coping resources and subjective well-being of dual-career Hindu mothers.
- Full Text:
- Date Issued: 2007
- Authors: Prag, Hanita T
- Date: 2007
- Subjects: Women -- India , Women -- Employment -- India , Hindu women -- Social life and customs
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9932 , http://hdl.handle.net/10948/593 , Women -- India , Women -- Employment -- India , Hindu women -- Social life and customs
- Description: With the increasing number of women entering the labour force internationally, the role of women is changing. Consequently, researchers are pressed to investigate how females of all cultures balance their work and family responsibilities. Amongst Hindu couples, this issue can either be a source of tension or positive support. An overview of literature indicates that the psychological aspects of dual-career Hindu women have received little attention in South Africa. The current study aimed to explore and describe coping resources and the subjective well-being of full-time employed Hindu mothers. The study took the form of a non-experimental exploratory-descriptive design. Participants were selected through nonprobability convenience sampling. The sample of the study consisted of sixty full-time employed Hindu mothers between the ages of 25 and 45 years of age who had at least one dependent primary school child aged between 7 to 12 years. Various questionnaires were used to collect data for this study. These included a Biographical Questionnaire, The Coping Resources Inventory (CRI), The Satisfaction with Life Scale (SWLS), and The Affectometer 2 (AFM2). Data was analysed by means of descriptive statistics. Cronbach’s coefficient alphas were utilised to calculate the reliability of the scores of each questionnaire. A multivariate technique was used to determine the amount of clusters formed. A non-hierarchical partitioning technique known as K-means cluster analysis was utilised in this study. An analysis of variance (ANOVA) was utilised in order to compare the mean scores of the various clusters. A post-hoc analysis using the Scheffé test was computed to test for significant differences. Cohen’s d statistics was subsequently used to determine the practical significance of the differences found between the cluster means on each of the measures. The cluster analysis indicated three clusters that differed significantly from one another on all three measures. The results of the CRI indicated that the participants used cognitive and spiritual resources to assist them to cope with the transition from traditional to modern contemporary roles. It was also found that the participants with low coping resources had inferior subjective well-being compared to those who had average and high CRI scores. The findings indicated that the participants were generally satisfied with their lives and experienced high levels of positive affect and low levels of negative affect. However, as a group there was a trend for the participants to have experienced slightly lower levels of global happiness or slightly negative affect. The results of this study broadens the knowledge base of positive psychology with respect to the diverse cultures and gender roles within South Africa. Overall, this study highlighted the value and the need for South African research on the coping resources and subjective well-being of dual-career Hindu mothers.
- Full Text:
- Date Issued: 2007
The design and assessment of an integrated municipal waste beneficiation facility : towards improved sewage sludge management in developing countries
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
- Date Issued: 2007
- Authors: Keirungi, Juliana
- Date: 2007
- Subjects: Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4755 , http://hdl.handle.net/10962/d1007138 , Sewage -- Purification -- South Africa -- Eastern Cape , Sewage sludge -- South Africa -- Eastern Cape -- Management , Water quality management -- South Africa -- Eastern Cape
- Description: This research aimed to firstly confirm the hypothesis that the current management of sewage sludge generated during the treatment of wastewater in the Eastern Cape Province of South Africa is poor and, as such, this material poses a threat to local environmental and human health. Secondly, through a rational design approach, the current research also aimed to design and assess the suitability of a novel integrated process incorporating appropriate technologies for improved sewage sludge management. The lack of an appropriate tool for the assessment of the integrated process necessitated the development of an appropriate technology assessment (TA) methodology based on environmental, technical, social and economic criteria. A combination of informal participatory methods such as semi-structured interviews and formal research methods including questionnaires, risk assessment exercises and laboratory analyses were used. Based on the above it was estimated that 116 tons dry sludge were generated in the province per day and that the concentration of heavy metals present in the sludge was generally within the limits for reuse on agricultural land. Furthermore the sludge from all sample sewage treatment works (STWs) was found to be free of any detectable pathogens. Despite the above, a preliminary risk assessment and chemical analysis revealed that existing sludge management practices at sample STWs posed a threat to the environment, particularly to water resources and exacerbated the problems associated with the discharge of poorly treated municipal wastewater. The root causes of the poor sludge management were considered to be a lack of non-regulatory incentives and financial resources. Highly integrated ecologically engineered systems were thought to offer a solution to the dual problem of poor sludge management and municipal effluent treatment, while providing necessary economic incentives. To facilitate the design of a system appropriate to local conditions, it was necessary to first develop a rational design methodology, which incorporated a detailed TA step. The result of the design process was an Integrated Waste Beneficiation Facility (IWBF) that incorporated a number of process units comprised of appropriate technologies including composting, vermicomposting, algal ponding technology and aquaculture. A detailed TA indicated that the benefits of the proposed IWBF would, at the majority of sample sites, outweigh the potential negative impacts and it was thus recommended that investigations should continue on pilot-scale facilities. Furthermore, although the proposed TA based on four sustainability criteria categories was thought to provide a more accurate assessment of the true sustainability of a technology, the acquisition of information was problematic highlighting the need to re-think current TA methodologies and to address associated constraints allowing the tool to be used and fully comprehensive.
- Full Text:
- Date Issued: 2007
The effect of elephants (Loxodonta africana, Blumenbach, 1797) on Xeric Succulent Thicket
- Authors: Knott, Edward Joseph
- Date: 2007
- Subjects: Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5674 , http://hdl.handle.net/10962/d1005359 , Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Description: This study looks at the impact of elephant feeding on the Xeric Succulent Thicket component of Eastern Cape Subtropical Thicket (ECST) in Addo Elephant National Park (AENP). Observations of elephant feeding were carried out and vegetation transects were surveyed for impact of elephant feeding. The results indicated that the Nyati elephants spent the majority of their time grazing (nearly 90%), particularly the cow-young herds, and especially when the herd gathered in larger numbers. Browsing events were concentrated on Acacia karroo (81%) and there was no significant difference between the sexes in their preference for this species. Despite being subjected to most of the browsing, the majority of A. karroo trees were undamaged and the effect of elephants was generally light. It appears unlikely that, three years after re-introduction to Nyati, the elephants have had an effect on community structure of the vegetation. Surveys were conducted on stands of the alien invasive weed prickly pear Opuntia ficus-indica, and it was recorded that elephants in Nyati have had a dramatic effect on prickly pear, utilising all adult plants assessed and destroying 70% of them. This level of destruction in such a short period of time suggests that prickly pear is a highly favoured species. The results from the present study suggest that elephants can play a role in the control of prickly pear. Results are discussed in terms of elephants as both megaherbivores and keystone species, and as agents of intermediate disturbance.
- Full Text:
- Date Issued: 2007
- Authors: Knott, Edward Joseph
- Date: 2007
- Subjects: Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5674 , http://hdl.handle.net/10962/d1005359 , Addo Elephant National Park (South Africa) , African elephant , Elephants -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Succulent plants -- South Africa -- Eastern Cape , Woody plants -- South Africa -- Eastern Cape
- Description: This study looks at the impact of elephant feeding on the Xeric Succulent Thicket component of Eastern Cape Subtropical Thicket (ECST) in Addo Elephant National Park (AENP). Observations of elephant feeding were carried out and vegetation transects were surveyed for impact of elephant feeding. The results indicated that the Nyati elephants spent the majority of their time grazing (nearly 90%), particularly the cow-young herds, and especially when the herd gathered in larger numbers. Browsing events were concentrated on Acacia karroo (81%) and there was no significant difference between the sexes in their preference for this species. Despite being subjected to most of the browsing, the majority of A. karroo trees were undamaged and the effect of elephants was generally light. It appears unlikely that, three years after re-introduction to Nyati, the elephants have had an effect on community structure of the vegetation. Surveys were conducted on stands of the alien invasive weed prickly pear Opuntia ficus-indica, and it was recorded that elephants in Nyati have had a dramatic effect on prickly pear, utilising all adult plants assessed and destroying 70% of them. This level of destruction in such a short period of time suggests that prickly pear is a highly favoured species. The results from the present study suggest that elephants can play a role in the control of prickly pear. Results are discussed in terms of elephants as both megaherbivores and keystone species, and as agents of intermediate disturbance.
- Full Text:
- Date Issued: 2007
The importance of dry woodlands and forests in rural livelihoods and poverty alleviation in South Africa
- Shackleton, Charlie M, Shackleton, Sheona E, Buiten, Erik, Bird, Neil
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Buiten, Erik , Bird, Neil
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6653 , http://hdl.handle.net/10962/d1007066
- Description: Indigenous forests and savannas, along with plantation forests, offer numerous benefits to rural communities and society at large. Yet, the role of forests and forestry in contributing to sustainable livelihoods and poverty alleviation are widely debated. However, much of the debate pertains to lessons from the humid tropics, with little consideration of the widespread dry forests and savannas. This paper considers the role of dry forest types, including savannas, using South Africa as a case example. It concludes that a large proportion of the population makes use of forests and the resources from them. These are vital components of local livelihoods, which probably prevent people from slipping into deeper poverty. Moreover, for a measurable proportion, engagement in informal forest activities, as well as the formal forestry sector, has resulted in them being able to move out of poverty. Additionally, the generally dry nature of forests in South Africa, coupled with the high unemployment rate, limit the extent of alternative locally based livelihood options, thereby magnifying the contributions from forests and forest products. The depressing effects of widespread HIV/AIDS on labour availability, economic activities and livelihoods has exacerbated peoples' dependence on forest products.
- Full Text:
- Date Issued: 2007
- Authors: Shackleton, Charlie M , Shackleton, Sheona E , Buiten, Erik , Bird, Neil
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6653 , http://hdl.handle.net/10962/d1007066
- Description: Indigenous forests and savannas, along with plantation forests, offer numerous benefits to rural communities and society at large. Yet, the role of forests and forestry in contributing to sustainable livelihoods and poverty alleviation are widely debated. However, much of the debate pertains to lessons from the humid tropics, with little consideration of the widespread dry forests and savannas. This paper considers the role of dry forest types, including savannas, using South Africa as a case example. It concludes that a large proportion of the population makes use of forests and the resources from them. These are vital components of local livelihoods, which probably prevent people from slipping into deeper poverty. Moreover, for a measurable proportion, engagement in informal forest activities, as well as the formal forestry sector, has resulted in them being able to move out of poverty. Additionally, the generally dry nature of forests in South Africa, coupled with the high unemployment rate, limit the extent of alternative locally based livelihood options, thereby magnifying the contributions from forests and forest products. The depressing effects of widespread HIV/AIDS on labour availability, economic activities and livelihoods has exacerbated peoples' dependence on forest products.
- Full Text:
- Date Issued: 2007
The medicinal chemistry of cyclo (Ser-Ser) and cyclo (Ser-Tyr)
- Authors: Kritzinger, André Louis
- Date: 2007
- Subjects: Cyclic peptides , Peptide drugs -- Therapeutic use , Haematostasis , Pharmaceutical chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10155 , http://hdl.handle.net/10948/537 , http://hdl.handle.net/10948/d1011712 , Cyclic peptides , Peptide drugs -- Therapeutic use , Haematostasis , Pharmaceutical chemistry
- Description: Cyclic dipeptides are widely used as models for larger peptides because of their simplicity and limited conformational freedom. Some cyclic dipeptides have been shown to produce antiviral, antibiotic and anti-tumour activity (Milne et al., 1998). In this study the cyclic dipeptides, cyclo(Ser-Ser) and cyclo(Ser-Tyr), were synthesised from their corresponding linear precursors using a modified phenolinduced cyclisation procedure. The phenol-induced cyclisation procedure resulted in good yields and purity of the cyclic dipeptides. Quantitative analysis and evaluation of the physicochemical properties of the cyclic dipeptides was achieved by using high-performance liquid chromatography, scanning electron microscopy, thermal analysis and X-ray powder diffraction. The structures of the synthesised cyclic dipeptides were elucidated using infrared spectroscopy, mass spectrometry, nuclear magnetic resonance spectroscopy and molecular modelling. The study aimed to determine the biological activity of cyclo(Ser-Ser) and cyclo(Ser-Tyr) with respect to their anticancer, antimicrobial, haematological and cardiac effects. Anticancer studies revealed that cyclo(Ser-Ser) and cyclo(Ser- Tyr) inhibited the growth of HeLa (cervical cancer), HT-29 (colon cancer) and MCF (breast cancer) cancer cell lines. Both cyclic dipeptides also inhibited the growth of certain selected Gram-positive, Gram-negative and fungal microorganisms in the antimicrobial study. Although the inhibition of growth in the anticancer and antimicrobial studies was statistically significant, the clinical relevance is questionable, since the inhibition produced by both cyclic dipeptides was very limited compared to other pre-existing anticancer and antimicrobial agents. Cyclo(Ser-Tyr) exhibited significant activity in the haematological studies, where it increased the rate of calcium induced-coagulation, and decreased the rate of streptokinase-induced fibrinolysis. Both cyclic dipeptides, however, failed to produce any significant effects on thrombin-substrate binding and ADPinduced platelet aggregation. Cardiac studies revealed that cyclo(Ser-Ser) and especially cyclo(Ser-Tyr) reduced the heart rate, coronary flow rate and ventricular pressure of isolated rat hearts.
- Full Text:
- Date Issued: 2007
- Authors: Kritzinger, André Louis
- Date: 2007
- Subjects: Cyclic peptides , Peptide drugs -- Therapeutic use , Haematostasis , Pharmaceutical chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10155 , http://hdl.handle.net/10948/537 , http://hdl.handle.net/10948/d1011712 , Cyclic peptides , Peptide drugs -- Therapeutic use , Haematostasis , Pharmaceutical chemistry
- Description: Cyclic dipeptides are widely used as models for larger peptides because of their simplicity and limited conformational freedom. Some cyclic dipeptides have been shown to produce antiviral, antibiotic and anti-tumour activity (Milne et al., 1998). In this study the cyclic dipeptides, cyclo(Ser-Ser) and cyclo(Ser-Tyr), were synthesised from their corresponding linear precursors using a modified phenolinduced cyclisation procedure. The phenol-induced cyclisation procedure resulted in good yields and purity of the cyclic dipeptides. Quantitative analysis and evaluation of the physicochemical properties of the cyclic dipeptides was achieved by using high-performance liquid chromatography, scanning electron microscopy, thermal analysis and X-ray powder diffraction. The structures of the synthesised cyclic dipeptides were elucidated using infrared spectroscopy, mass spectrometry, nuclear magnetic resonance spectroscopy and molecular modelling. The study aimed to determine the biological activity of cyclo(Ser-Ser) and cyclo(Ser-Tyr) with respect to their anticancer, antimicrobial, haematological and cardiac effects. Anticancer studies revealed that cyclo(Ser-Ser) and cyclo(Ser- Tyr) inhibited the growth of HeLa (cervical cancer), HT-29 (colon cancer) and MCF (breast cancer) cancer cell lines. Both cyclic dipeptides also inhibited the growth of certain selected Gram-positive, Gram-negative and fungal microorganisms in the antimicrobial study. Although the inhibition of growth in the anticancer and antimicrobial studies was statistically significant, the clinical relevance is questionable, since the inhibition produced by both cyclic dipeptides was very limited compared to other pre-existing anticancer and antimicrobial agents. Cyclo(Ser-Tyr) exhibited significant activity in the haematological studies, where it increased the rate of calcium induced-coagulation, and decreased the rate of streptokinase-induced fibrinolysis. Both cyclic dipeptides, however, failed to produce any significant effects on thrombin-substrate binding and ADPinduced platelet aggregation. Cardiac studies revealed that cyclo(Ser-Ser) and especially cyclo(Ser-Tyr) reduced the heart rate, coronary flow rate and ventricular pressure of isolated rat hearts.
- Full Text:
- Date Issued: 2007
The mutual embodiment of landscape and livelihoods: an environmental history of Nqabara
- Authors: De Klerk, Henning
- Date: 2007
- Subjects: Land reform -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Landscapes -- Social aspects -- South Africa -- Eastern Cape , Landscape ecology -- South Africa -- Eastern Cape , Land use, Rural -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4750 , http://hdl.handle.net/10962/d1007054 , Land reform -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Landscapes -- Social aspects -- South Africa -- Eastern Cape , Landscape ecology -- South Africa -- Eastern Cape , Land use, Rural -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Description: This thesis presents a history of the landscape of Nqabara, an administrative area in a rural and coastal area of the Eastern Cape Province, South Africa. In the process of investigating landscape history, the inquiry engages with a range of data sources from diverging discursive contexts, including data from ethnographic fieldwork, from the consultation of archival documents and historical reports as well as from comparative historic and ethnographic research, necessitating a critical consideration of the epistemological contexts of data production and the dialogue between researcher and data. Furthermore, in its aim to move beyond historical description towards explanation, the study interrogates the dualist ontological conceptualisations of nature and culture, society and ecology, object and meaning upon which are built three dominant conceptual frameworks concerned with human-environment relationships: social-ecological systems theory, transdisciplinary landscape studies and political ecology. Drawing primarily upon the works of James Gibson, Anthony Giddens and Tim Ingold, an ontological foundation is developed to guide the enquiry and move towards an alternative understanding of the relationship of people’s livelihoods with respect to the landscape in which it is lived, which I call here the praxisembodiment perspective. This ontology takes the situated patterns of action of a situated agent-in-its-environment as its point of departure and proceeds to develop a framework explaining how relations among the patterns of action of different agents-in-their-environment, emerge in structures that simultaneously enable and constrain future action. The foundation is thereby provided for a monist understanding of how landscape and social structure emerge simultaneously from the complex intersection of patterns of actions and interactions of agents in their environment. This framework calls for an understanding of time, space and scale, not as independent variables influencing process and action, but as emergent properties arising from the patterns of actions of situated agents. Finally the alternative ontology is applied to the history of landscape and livelihoods of people of Nqabara. It is concluded that an appropriate understanding and explanation of the critical transformations in the landscape as well as in social institutions, should be sought through analysis of the complex ways in which patterns of action of multiple spatial and temporal rhythms and between multiple agents in an environment, intersect and resonate.
- Full Text:
- Date Issued: 2007
- Authors: De Klerk, Henning
- Date: 2007
- Subjects: Land reform -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Landscapes -- Social aspects -- South Africa -- Eastern Cape , Landscape ecology -- South Africa -- Eastern Cape , Land use, Rural -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4750 , http://hdl.handle.net/10962/d1007054 , Land reform -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Landscapes -- Social aspects -- South Africa -- Eastern Cape , Landscape ecology -- South Africa -- Eastern Cape , Land use, Rural -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape
- Description: This thesis presents a history of the landscape of Nqabara, an administrative area in a rural and coastal area of the Eastern Cape Province, South Africa. In the process of investigating landscape history, the inquiry engages with a range of data sources from diverging discursive contexts, including data from ethnographic fieldwork, from the consultation of archival documents and historical reports as well as from comparative historic and ethnographic research, necessitating a critical consideration of the epistemological contexts of data production and the dialogue between researcher and data. Furthermore, in its aim to move beyond historical description towards explanation, the study interrogates the dualist ontological conceptualisations of nature and culture, society and ecology, object and meaning upon which are built three dominant conceptual frameworks concerned with human-environment relationships: social-ecological systems theory, transdisciplinary landscape studies and political ecology. Drawing primarily upon the works of James Gibson, Anthony Giddens and Tim Ingold, an ontological foundation is developed to guide the enquiry and move towards an alternative understanding of the relationship of people’s livelihoods with respect to the landscape in which it is lived, which I call here the praxisembodiment perspective. This ontology takes the situated patterns of action of a situated agent-in-its-environment as its point of departure and proceeds to develop a framework explaining how relations among the patterns of action of different agents-in-their-environment, emerge in structures that simultaneously enable and constrain future action. The foundation is thereby provided for a monist understanding of how landscape and social structure emerge simultaneously from the complex intersection of patterns of actions and interactions of agents in their environment. This framework calls for an understanding of time, space and scale, not as independent variables influencing process and action, but as emergent properties arising from the patterns of actions of situated agents. Finally the alternative ontology is applied to the history of landscape and livelihoods of people of Nqabara. It is concluded that an appropriate understanding and explanation of the critical transformations in the landscape as well as in social institutions, should be sought through analysis of the complex ways in which patterns of action of multiple spatial and temporal rhythms and between multiple agents in an environment, intersect and resonate.
- Full Text:
- Date Issued: 2007