Anti-diabetic and phytochemical analysis of sutherlandia frutescens extracts
- Authors: Adefuye, Ogheneochuko Janet
- Date: 2016
- Subjects: Medicinal plants -- Africa , Traditional medicine -- Africa , Herbs -- Therapeutic use -- Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/3549 , vital:20441
- Description: In Africa, the importance of medicinal plants in folklore medicine and their contribution to primary healthcare is well recognized. Across the continent, local herbal mixtures still provide the only therapeutic option for about 80% of the population. The vast floral diversity and the intrinsic ethnobotanical knowledge has been the backbone of localized traditional herbal medical practices. In Africa, an estimated 5400 of the 60000 described plant taxa possess over 16300 therapeutic uses. Similarly, with a therapeutic flora comprising of approximately 650 species, herbal medical practitioners in South Africa, make use of a plethora of plants to treat different human diseases and infections. Over the years, studies have identified numerous plant species with potential against chronic metabolic diseases including type 2 diabetes mellitus (T2DM). Globally, the incidence and prevalence of T2DM have reached epidemic proportions affecting people of all ages, nationalities and ethnicity. Considered the fourth leading cause of deaths by disease, T2DM is a global health crisis with an estimated diagnosis and mortality frequency of 1 every 5 seconds and 1 every 7 seconds respectively. Though the exact pathophysiology of T2DM is not entirely understood, initial peripheral insulin resistance in adipose tissue, liver, and skeletal muscle with subsequent pancreatic β-cell dysfunction resulting from an attempt to compensate for insulin resistance is a common feature of the disease. The current approach to treating T2DM is the use of oral antidiabetic agents (OAAs), insulin, and incretin-based drugs in an attempt to achieve glycaemic control and maintain glucose homeostasis. However, conventional anti-T2DM drugs have been shown to have limited efficacies and serious adverse effects. Hence, the need for newer, more efficacious and safer anti-T2DM agents. Sutherlandia frutescens subsp. microphylla is a flowering shrub of the pea family (Fabaceae/Leguminaceae) found mainly in the Western Cape and Karoo regions of Southern Africa. Concoctions of various parts of the plant are used in the management of different ailments including T2DM. However, despite extensive biological and pharmacological studies, few analyses exist of the chemical constituents of S. frutescens and no Triple Time of Flight Liquid Chromatography with Mass Spectrometry (Triple TOF LC/MS/MS) analysis has been performed. The initial aim of this study was to investigate the phytochemical profile of hot aqueous, cold aqueous, 80% ethanolic, 100% ethanolic, 80% methanolic and 100% methanolic extracts of a single source S. frutescens plant material using colorimetric and spectrophotometric analysis. The hot aqueous extractant was found to be the best extractant for S. frutescens, yielding 1.99 g of crude extract from 16 g fresh powdered plant material. This data suggests that application of heat and water as the extractant (hot aqueous) could play a vital role in extraction of bioactive compounds from S. frutescens and also justifies the traditional use of a tea infusion of S. frutescens. Colorimetric analysis revealed the presence of flavonoids, flavonols, tannins, and phenols in all extracts with varying intensity. The organic extracts 100% methanol, 80% and 100% ethanol exhibited high color intensity (+++) for flavonoids and flavonols respectively, while all the extracts exhibited a moderate color intensity (++) for tannins and phenols. Spectrophotometric analysis of S. frutescens extracts revealed that all the organic extracts contained a significantly higher concentration (in mg/g of extract) of flavonols and tannins when compared to the aqueous extracts. All extracts contained approximately equal levels of phenols. These data confirm the presence of all four groups of bioactive phytocompounds in the S. frutescens extracts used in this study, and also confirm that different solvent extractants possess the capability to differentially extract specific groups of phytocompounds. in individual extracts. Further comparison of these compounds with online databases of anti-diabetic phytocompounds led to the preliminary identification of 10 possible anti-diabetic compounds; α-Pinene, Limonene, Sabinene, Carvone, Myricetin, Rutin, Stigmasterol, Emodin, Sarpagine and Hypoglycin B in crude and solid phase extraction (SPE) fractions of S. frutesecens. Furthermore, using two hepatic cell lines (Chang and HepG2) as an in-vtro model system, the anti-T2DM properties of crude aqueous and organic extracts of S. frutescents was investigated and compared. Both aqueous and organic extracts of S. frutescens were found to decrease gluconeogenesis, increase glucose uptake and decrease lipid accumulation (Triacylglycerol, Diacylglycerol, and Monoacylglycerol) in Chang and HepG2 hepatic cell cultures made insulin resistant (IR) following exposure to high concentration of insulin and fructose. Using real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), the aqueous and organic extracts of S. frutescens were confirmed to regulate the expression of Vesicle-associated membrane protein 3 (VAMP3), Mitogen-activated protein kinase 8 (MAPK8), and Insulin receptor substrate 1 (IRS1) in insulin resistant hepatic cells. IR-mediated downregulation of VAMP3, MAPK8, and IRS1 mRNA in IR HepG2 hepatic cell cultures was reversed in the presence of aqueous and organic extracts of S. frutescens. The hot aqueous extract displayed the highest activity in all the assays, while all the organic extracts displayed similar potency. In conclusion, this study reports that aqueous and organic extracts of S. frutescens possess numerous anti-diabetic compounds that can be further investigated for the development of new, more efficacious and less toxic anti-diabetic agents. The presence of multiple compounds in a single extract does suggest a synergistic or combinatorial therapeutic effect. These findings support the burgeoning body of in-vivo and in-vitro literature evidence on the anti-diabetic properties of S. frutescens and its use in folklore medicine.
- Full Text:
- Date Issued: 2016
- Authors: Adefuye, Ogheneochuko Janet
- Date: 2016
- Subjects: Medicinal plants -- Africa , Traditional medicine -- Africa , Herbs -- Therapeutic use -- Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/3549 , vital:20441
- Description: In Africa, the importance of medicinal plants in folklore medicine and their contribution to primary healthcare is well recognized. Across the continent, local herbal mixtures still provide the only therapeutic option for about 80% of the population. The vast floral diversity and the intrinsic ethnobotanical knowledge has been the backbone of localized traditional herbal medical practices. In Africa, an estimated 5400 of the 60000 described plant taxa possess over 16300 therapeutic uses. Similarly, with a therapeutic flora comprising of approximately 650 species, herbal medical practitioners in South Africa, make use of a plethora of plants to treat different human diseases and infections. Over the years, studies have identified numerous plant species with potential against chronic metabolic diseases including type 2 diabetes mellitus (T2DM). Globally, the incidence and prevalence of T2DM have reached epidemic proportions affecting people of all ages, nationalities and ethnicity. Considered the fourth leading cause of deaths by disease, T2DM is a global health crisis with an estimated diagnosis and mortality frequency of 1 every 5 seconds and 1 every 7 seconds respectively. Though the exact pathophysiology of T2DM is not entirely understood, initial peripheral insulin resistance in adipose tissue, liver, and skeletal muscle with subsequent pancreatic β-cell dysfunction resulting from an attempt to compensate for insulin resistance is a common feature of the disease. The current approach to treating T2DM is the use of oral antidiabetic agents (OAAs), insulin, and incretin-based drugs in an attempt to achieve glycaemic control and maintain glucose homeostasis. However, conventional anti-T2DM drugs have been shown to have limited efficacies and serious adverse effects. Hence, the need for newer, more efficacious and safer anti-T2DM agents. Sutherlandia frutescens subsp. microphylla is a flowering shrub of the pea family (Fabaceae/Leguminaceae) found mainly in the Western Cape and Karoo regions of Southern Africa. Concoctions of various parts of the plant are used in the management of different ailments including T2DM. However, despite extensive biological and pharmacological studies, few analyses exist of the chemical constituents of S. frutescens and no Triple Time of Flight Liquid Chromatography with Mass Spectrometry (Triple TOF LC/MS/MS) analysis has been performed. The initial aim of this study was to investigate the phytochemical profile of hot aqueous, cold aqueous, 80% ethanolic, 100% ethanolic, 80% methanolic and 100% methanolic extracts of a single source S. frutescens plant material using colorimetric and spectrophotometric analysis. The hot aqueous extractant was found to be the best extractant for S. frutescens, yielding 1.99 g of crude extract from 16 g fresh powdered plant material. This data suggests that application of heat and water as the extractant (hot aqueous) could play a vital role in extraction of bioactive compounds from S. frutescens and also justifies the traditional use of a tea infusion of S. frutescens. Colorimetric analysis revealed the presence of flavonoids, flavonols, tannins, and phenols in all extracts with varying intensity. The organic extracts 100% methanol, 80% and 100% ethanol exhibited high color intensity (+++) for flavonoids and flavonols respectively, while all the extracts exhibited a moderate color intensity (++) for tannins and phenols. Spectrophotometric analysis of S. frutescens extracts revealed that all the organic extracts contained a significantly higher concentration (in mg/g of extract) of flavonols and tannins when compared to the aqueous extracts. All extracts contained approximately equal levels of phenols. These data confirm the presence of all four groups of bioactive phytocompounds in the S. frutescens extracts used in this study, and also confirm that different solvent extractants possess the capability to differentially extract specific groups of phytocompounds. in individual extracts. Further comparison of these compounds with online databases of anti-diabetic phytocompounds led to the preliminary identification of 10 possible anti-diabetic compounds; α-Pinene, Limonene, Sabinene, Carvone, Myricetin, Rutin, Stigmasterol, Emodin, Sarpagine and Hypoglycin B in crude and solid phase extraction (SPE) fractions of S. frutesecens. Furthermore, using two hepatic cell lines (Chang and HepG2) as an in-vtro model system, the anti-T2DM properties of crude aqueous and organic extracts of S. frutescents was investigated and compared. Both aqueous and organic extracts of S. frutescens were found to decrease gluconeogenesis, increase glucose uptake and decrease lipid accumulation (Triacylglycerol, Diacylglycerol, and Monoacylglycerol) in Chang and HepG2 hepatic cell cultures made insulin resistant (IR) following exposure to high concentration of insulin and fructose. Using real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), the aqueous and organic extracts of S. frutescens were confirmed to regulate the expression of Vesicle-associated membrane protein 3 (VAMP3), Mitogen-activated protein kinase 8 (MAPK8), and Insulin receptor substrate 1 (IRS1) in insulin resistant hepatic cells. IR-mediated downregulation of VAMP3, MAPK8, and IRS1 mRNA in IR HepG2 hepatic cell cultures was reversed in the presence of aqueous and organic extracts of S. frutescens. The hot aqueous extract displayed the highest activity in all the assays, while all the organic extracts displayed similar potency. In conclusion, this study reports that aqueous and organic extracts of S. frutescens possess numerous anti-diabetic compounds that can be further investigated for the development of new, more efficacious and less toxic anti-diabetic agents. The presence of multiple compounds in a single extract does suggest a synergistic or combinatorial therapeutic effect. These findings support the burgeoning body of in-vivo and in-vitro literature evidence on the anti-diabetic properties of S. frutescens and its use in folklore medicine.
- Full Text:
- Date Issued: 2016
Antibacterial effects of Alchornea cordifolia (Schumach. and Thonn.) Müll. Arg extracts and compounds on gastrointestinal, skin, respiratory and urinary tract pathogens
- Siwe-Noundou, Xavier, Krause, Rui W M, van Vuuren, Sandy, Tantoh Ndinteh, Derek, Olivier, Denise K
- Authors: Siwe-Noundou, Xavier , Krause, Rui W M , van Vuuren, Sandy , Tantoh Ndinteh, Derek , Olivier, Denise K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195418 , vital:45563 , xlink:href="https://doi.org/10.1016/j.jep.2015.12.043"
- Description: Ethnopharmacological relevance:The leaves, stems and roots ofAlchornea cordifolia(Schumach. andThonn.) Müll. Arg. are used as traditional medicine in many African countries for the management ofgastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds.Aim of the study:To determine the in vitro antibacterial activity of the crude extracts of leaves and stemsofA. cordifoliaon gastrointestinal, skin, respiratory and urinary tract pathogens and to identify thecompounds in the extracts that may be responsible for this activity.Materials and methods:The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethylacetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolatedfrom these extracts were evaluated by means of the micro-dilution assay against four Gram-positivebacteria, i.e.Bacillus cereusATCC 11778,Enterococcus faecalisATCC 29212, Staphylococcus aureusATCC25923 andS. saprophyticusATCC 15305,as well as four Gram-negative bacterial strains, i.e.EscherichiacoliATCC 25922, Klebsiella pneumoniaeATCC 13883, Moraxella catarrhalisATCC 23246 andProteus mir-abilisATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays inconjunction with chromatographic techniques. The identification and characterisation of the isolatedcompounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry(FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses.Results:The leaves and stems ofA. cordifoliaexhibited varied antibacterial activity against all eight pa-thogens. Most of the MIC values ranged between 63 and 2000mg/ml. The highest activities for the crudeextracts (63mg/ml) were observed againstS. saprophyticus[stem (EtOAc, CHCl3and hexane), leaves(MeOH, EtOH, EtOAc and CHCl3)],E. coli[stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc andCHCl3)],M. catarrhalis[leaves (EtOAc and CHCl3)],K. pneumoniae[stem (CHCl3), leaves (CHCl3)] andS.aureus[leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3),friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these com-pounds displayed some antibacterial activity against the eight pathogens with highest activity againstS.saprophyticus(2mg/ml). Furthermore, this is thefirst report of compounds1,2,3,4,6and7isolated fromA. cordifoliaand where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented.Conclusion:The study demonstrated that the antibacterial activities ofA. cordifoliaextracts may be dueto the presence of the seven isolated compounds, where compounds3–6showed the best activity. Theobserved activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports thetraditional use for the treatment of such ailments.
- Full Text:
- Date Issued: 2016
- Authors: Siwe-Noundou, Xavier , Krause, Rui W M , van Vuuren, Sandy , Tantoh Ndinteh, Derek , Olivier, Denise K
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/195418 , vital:45563 , xlink:href="https://doi.org/10.1016/j.jep.2015.12.043"
- Description: Ethnopharmacological relevance:The leaves, stems and roots ofAlchornea cordifolia(Schumach. andThonn.) Müll. Arg. are used as traditional medicine in many African countries for the management ofgastrointestinal, respiratory and urinary tract infections as well as for the treatment of wounds.Aim of the study:To determine the in vitro antibacterial activity of the crude extracts of leaves and stemsofA. cordifoliaon gastrointestinal, skin, respiratory and urinary tract pathogens and to identify thecompounds in the extracts that may be responsible for this activity.Materials and methods:The antibacterial activities of crude extracts [hexane, chloroform (CHCl3), ethylacetate (EtOAc), ethanol (EtOH), methanol (MeOH) and water (H2O)] as well as pure compounds isolatedfrom these extracts were evaluated by means of the micro-dilution assay against four Gram-positivebacteria, i.e.Bacillus cereusATCC 11778,Enterococcus faecalisATCC 29212, Staphylococcus aureusATCC25923 andS. saprophyticusATCC 15305,as well as four Gram-negative bacterial strains, i.e.EscherichiacoliATCC 25922, Klebsiella pneumoniaeATCC 13883, Moraxella catarrhalisATCC 23246 andProteus mir-abilisATCC 43071. The isolation of the active constituents was undertaken by bio-autographic assays inconjunction with chromatographic techniques. The identification and characterisation of the isolatedcompounds were done using mass spectrometry (MS) and Fourier transformed infrared spectrometry(FTIR) as well as 1D- and 2D- nuclear magnetic resonance (NMR) analyses.Results:The leaves and stems ofA. cordifoliaexhibited varied antibacterial activity against all eight pa-thogens. Most of the MIC values ranged between 63 and 2000mg/ml. The highest activities for the crudeextracts (63mg/ml) were observed againstS. saprophyticus[stem (EtOAc, CHCl3and hexane), leaves(MeOH, EtOH, EtOAc and CHCl3)],E. coli[stem (MeOH and EtOH), leaves (MeOH, EtOH, EtOAc andCHCl3)],M. catarrhalis[leaves (EtOAc and CHCl3)],K. pneumoniae[stem (CHCl3), leaves (CHCl3)] andS.aureus[leaves (CHCl3)]. Seven constituents [stigmasterol (1), stigmasta-4,22-dien-3-one (2), friedelin (3),friedelane-3-one-28-al (4), 3-O-acetyl-aleuritolic acid (5), 3-O-acetyl-erythrodiol (6) and methyl-3,4,5-trihydroxybenzoate (methyl gallate) (7)] were isolated from the stem MeOH extract. All these com-pounds displayed some antibacterial activity against the eight pathogens with highest activity againstS.saprophyticus(2mg/ml). Furthermore, this is thefirst report of compounds1,2,3,4,6and7isolated fromA. cordifoliaand where a complete set of 2D-NMR data for fridelane-3-one-28-al (4) is presented.Conclusion:The study demonstrated that the antibacterial activities ofA. cordifoliaextracts may be dueto the presence of the seven isolated compounds, where compounds3–6showed the best activity. Theobserved activity against gastrointestinal, skin, respiratory and urinary tract pathogens supports thetraditional use for the treatment of such ailments.
- Full Text:
- Date Issued: 2016
Application of Baylis-Hillman methodology in the direct construction of chromone derivatives
- Faridoon, H, Olomola, Temitope O, Klein, Rosalyn, Kaye, Perry T
- Authors: Faridoon, H , Olomola, Temitope O , Klein, Rosalyn , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442488 , vital:73992 , https://doi.org/10.1016/j.tet.2015.11.039
- Description: Pyridinium chlorochromate oxidation of Baylis-Hillman-derived tert-butyl 2H-chromene-3-carboxylates affords chromone-3-carboxylate esters, providing the first application of Baylis-Hillman methodology in a direct and convenient three-step synthesis of chromone derivatives.
- Full Text:
- Date Issued: 2016
- Authors: Faridoon, H , Olomola, Temitope O , Klein, Rosalyn , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442488 , vital:73992 , https://doi.org/10.1016/j.tet.2015.11.039
- Description: Pyridinium chlorochromate oxidation of Baylis-Hillman-derived tert-butyl 2H-chromene-3-carboxylates affords chromone-3-carboxylate esters, providing the first application of Baylis-Hillman methodology in a direct and convenient three-step synthesis of chromone derivatives.
- Full Text:
- Date Issued: 2016
Appraising the national road transport system in the light of the South African economic development plan
- Authors: Potgieter, Andries Hendrik
- Date: 2016
- Subjects: Transportation -- South Africa , Economic development -- South Africa , Infrastructure (Economics) -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/3655 , vital:20450
- Description: Since the mid 70’s politicians have realized how important transport has become in the economy of South Africa and the advantages it has on growth, job creation and infrastructure. The result was involvement in the rules and regulations that govern South African transport in our country today. Economic growth has become a critical factor for the survival of economies as well as the future prospects of generations to come. The global recession which had a direct and indirect effect on South Africa has highlighted the importance. The question on how the National Development Plan could have an influence on local and national economic growth has developed as well as what the impact will be of the contribution road transport can make on the growth of the South African society and the economy. When the current road transport sector is taken into consideration, the need for a constructive plan that can assist transporters, drivers and businesses to grow and expand has been identified. The purpose of this study is thus to determine what the current economic situation in the world and in South Africa is as well as how the current political spheres are contributing to the national economy. An in-depth analysis of the National Development Plan has been done with emphasis on the effect on transport in general and the effect on road transport in South Africa. In order to accomplish this objective a detailed literature study was done which highlighted the academics information that pertains to the above mentioned topics. An empirical study that would measure the thought process and feelings about the National Development Plan and road transport has been conducted by means of a questionnaire. The results of the study have indicated that the National Development Plan could be an important tool and could have an enormous positive effect on the overall economic situation of South Africa and its citizens. In addition, the study has revealed that in the long term the effect of the plan could be to the advantage of the road transport sector. Factors that could contribute to the success would be features such as the planned improvements on the main transport corridors, upgrade of infrastructure and the controlling of environmental matters would have give a positive ring to it. On the other hand, recommendations to rectify and improve other issues such as corruption, leadership, maintenance backlogs and stricter laws and policies have been identified that are hindering businesses to grow and expand. Literature and data gained through the empirical study has indicated that the National Development Plan will improve South Africa’s economic situation. Respondents were optimistic about the plan and the overall feeling were that the plan will succeed in improving the road transport sector thus contribute to the National Development Plan objective to eliminate poverty and inequality by 2030.
- Full Text:
- Date Issued: 2016
- Authors: Potgieter, Andries Hendrik
- Date: 2016
- Subjects: Transportation -- South Africa , Economic development -- South Africa , Infrastructure (Economics) -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/3655 , vital:20450
- Description: Since the mid 70’s politicians have realized how important transport has become in the economy of South Africa and the advantages it has on growth, job creation and infrastructure. The result was involvement in the rules and regulations that govern South African transport in our country today. Economic growth has become a critical factor for the survival of economies as well as the future prospects of generations to come. The global recession which had a direct and indirect effect on South Africa has highlighted the importance. The question on how the National Development Plan could have an influence on local and national economic growth has developed as well as what the impact will be of the contribution road transport can make on the growth of the South African society and the economy. When the current road transport sector is taken into consideration, the need for a constructive plan that can assist transporters, drivers and businesses to grow and expand has been identified. The purpose of this study is thus to determine what the current economic situation in the world and in South Africa is as well as how the current political spheres are contributing to the national economy. An in-depth analysis of the National Development Plan has been done with emphasis on the effect on transport in general and the effect on road transport in South Africa. In order to accomplish this objective a detailed literature study was done which highlighted the academics information that pertains to the above mentioned topics. An empirical study that would measure the thought process and feelings about the National Development Plan and road transport has been conducted by means of a questionnaire. The results of the study have indicated that the National Development Plan could be an important tool and could have an enormous positive effect on the overall economic situation of South Africa and its citizens. In addition, the study has revealed that in the long term the effect of the plan could be to the advantage of the road transport sector. Factors that could contribute to the success would be features such as the planned improvements on the main transport corridors, upgrade of infrastructure and the controlling of environmental matters would have give a positive ring to it. On the other hand, recommendations to rectify and improve other issues such as corruption, leadership, maintenance backlogs and stricter laws and policies have been identified that are hindering businesses to grow and expand. Literature and data gained through the empirical study has indicated that the National Development Plan will improve South Africa’s economic situation. Respondents were optimistic about the plan and the overall feeling were that the plan will succeed in improving the road transport sector thus contribute to the National Development Plan objective to eliminate poverty and inequality by 2030.
- Full Text:
- Date Issued: 2016
Aquatic–terrestrial trophic linkages via riverine invertebrates in a South African catchment
- Authors: Moyo, Sydney
- Date: 2016
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54427 , vital:26564
- Description: Rivers play a vital role in human livelihoods and are likely to undergo substantial alteration due to climate and land use changes from an increasing human population. Mitigating the pressures facing rivers in the world requires scientists and environmental managers to understand the ecological mechanisms, and ultimately the strength, of connections between ecosystems. This understanding of connections between adjacent habitats will enable environmental managers to predict the consequences of perturbing these linkages in the future. In this thesis, aquatic-terrestrial linkages in rivers were investigated using ecologically meaningful variables including abundances, biomasses, stable isotopes and fatty acids. This study is part of a larger project entitled “Connectivity through allochthony: reciprocal links between adjacent aquatic and terrestrial ecosystems in South Africa”, in which a team of researchers assessed a variety of pathways connecting riverine and estuarine systems to land within a catchment in the Eastern Cape, South Africa. I conceptualised the flow of energy within a temperate southern hemisphere river (the Kowie River) within theoretical models of energy flow such as the River Continuum Concept (RCC; presents lotic systems as being longitudinally linked with food webs in shaded headwaters being principally driven by allochthonous energy, with the addition of autochthonous food as a minor carbon source in the lower reaches) and the Riverine Productivity Model (RPM; proposes consumers derive most of their energy from local production of phytoplankton, benthic algae and aquatic plants, as well as directly from riparian zones via terrestrial leaf litter). Using the RCC as a starting point, I collected macroinvertebrates (September 2012 to May 2013) along a longitudinal gradient and grouped them into functional feeding groups (FFGs). The results revealed that gatherers and filterers dominated in the Kowie River, and together represented 50 – 83% of the invertebrate assemblages. There was a general paucity of shredders (relative abundance was ≤ 10% across all sites and seasons). The changes in relative abundances of different FFGs did not follow predictions of the RCC along the longitudinal gradient, as there were no correlations of community structure with some physical attributes (stream width, canopy cover, distance of river) that changed along the river continuum. However, FFG abundances were related to water velocity, total dissolved solids and canopy cover. Broadly, the Kowie River data showed that changes in relative abundances of FFGs along the river continuum could not be explained by changes in physical attributes alone, and may be highly influenced by the availability of food and the chemistry of the stream. Analysis of stable carbon (δ13C) and nitrogen (δ15N) isotopes was used to estimate the contributions of algal and land-based production to consumers over space (six sites) and time (November 2012 to September 2013). Carbon contributions determined by the use of mixing models (Stable Isotope Analysis in R) revealed that consumers in the headwater assimilated mainly terrestrially-derived organic matter, with consumers in the middle and lower reaches assimilating autochthonous basal resources (macrophytes and algae). The findings from this river supported aspects of the RCC (at the headwaters; terrestrial organic matter made up 41% of consumer diets), but overall the data supported the predictions of the RPM (local production made the highest contributions of 50 – 86% to all FFGs across all seasons). The carbon isotopes of consumers and their food sources changed substantially every season, indicating that samples of food sources and consumers should be analysed many times throughout the year to capture that variability and to ensure that ephemeral components of the food web are not missed. To validate the findings from the isotope data, fatty acids were used as complementary tracers to determine the contributions of algal versus terrestrial organic matter to the consumers. Fatty acid tracers for terrestrial (Ʃω3/Ʃω6; 18:2ω6; 18:3ω3) vs aquatic (Ʃω3/Ʃω6; 20:5ω3) sources corroborated the findings from the isotope data set, as the mean ratio of Ʃω3/Ʃω6 in consumers was less than one at the headwaters (indicating allochthony), while middle and lower reaches were associated with Ʃω3/Ʃω6 > 1 (indicating autochthony). In addition to the tracer and FFG analyses for examining trophic connections between land and river, the bidirectional exchange of organisms between the riparian zone and the river was assessed using floating pyramidal traps (to measure emergence) and pan traps (for infalling invertebrates) placed at different sites in the river and the biomass in each trap was determined. The exchanges were variable over space and time, with emergence peaking in summer (169 to 1402 mg m-2 day-1) and declining in winter (3 to 28 mg m-2 day-1). Similarly, infalling invertebrates increased in summer (413 to 679 mg m-2 day-1) and declined in winter (11 to 220 mg m-2 day-1). Biomass measurements are indications of quantity that ignore nutritional quality, so I determined the bidirectional flow of invertebrates using absolute concentrations of physiologically important biochemical compounds (essential and polyunsaturated fatty acids). The fluxes of emergent and infalling arthropods peaked in summer (emergence = 0.3 to 18 mg m-2 day-1 and terrestrial infall = 0.3 to 3 mg m-2 day-1) and declined in winter (emergence = 0.01 to 0.51 mg m-2 day-1 and terrestrial infall = 0.01 to 0.03 mg m-2 day-1). However, during some seasons, no significant differences in polyunsaturated fatty acid flux in either direction were observed; this finding indicated the balance of reciprocal subsidisation via reciprocal flows of animals. Factors such as air temperature and algal productivity affected the reciprocal flows between adjacent habitats, with algal productivity being positively related to emergence while air temperature was positively correlated to infalling terrestrial invertebrates. This research enhances the growing body of literature on the function of riverine systems and offers some invaluable information on the flow of energy and the role played by invertebrates in translocating nutrients from terrestrial systems to aquatic systems and vice versa. This study unifies the concepts of the RCC and RPM and shows that these concepts are not limited only to large rivers, but are applicable to small southern temperate rivers too. However, some tenets of the theoretical models were challenged. For example, it challenges the proposition by the RCC that the fine particulate organic matter leaked from upstream breakdown of coarse particulate organic matter is predominantly allochthonous. Additionally, this study showed that in the headwaters, the RPM underestimated the role of autochthony. Overall, the results showed that the Kowie River and its riparian area are intrinsically connected. Once we understand the mechanisms controlling connections and subsidies across ecotones, we can then start to predict the consequences of disruptions to these connections by climate change and/or land use changes. To make predictions about future perturbations to rivers and riparian zones, studies like this, which considers the form and magnitude of subsidies, are needed to provide baseline information. Algal resources (e.g. epiphyton), macrophytes, riparian plants, terrestrial organisms and aquatic organisms all contributed to aquatic and terrestrial linkages in the Kowie River; therefore, it is important to conserve the different components of these ecosystems.
- Full Text:
- Date Issued: 2016
- Authors: Moyo, Sydney
- Date: 2016
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54427 , vital:26564
- Description: Rivers play a vital role in human livelihoods and are likely to undergo substantial alteration due to climate and land use changes from an increasing human population. Mitigating the pressures facing rivers in the world requires scientists and environmental managers to understand the ecological mechanisms, and ultimately the strength, of connections between ecosystems. This understanding of connections between adjacent habitats will enable environmental managers to predict the consequences of perturbing these linkages in the future. In this thesis, aquatic-terrestrial linkages in rivers were investigated using ecologically meaningful variables including abundances, biomasses, stable isotopes and fatty acids. This study is part of a larger project entitled “Connectivity through allochthony: reciprocal links between adjacent aquatic and terrestrial ecosystems in South Africa”, in which a team of researchers assessed a variety of pathways connecting riverine and estuarine systems to land within a catchment in the Eastern Cape, South Africa. I conceptualised the flow of energy within a temperate southern hemisphere river (the Kowie River) within theoretical models of energy flow such as the River Continuum Concept (RCC; presents lotic systems as being longitudinally linked with food webs in shaded headwaters being principally driven by allochthonous energy, with the addition of autochthonous food as a minor carbon source in the lower reaches) and the Riverine Productivity Model (RPM; proposes consumers derive most of their energy from local production of phytoplankton, benthic algae and aquatic plants, as well as directly from riparian zones via terrestrial leaf litter). Using the RCC as a starting point, I collected macroinvertebrates (September 2012 to May 2013) along a longitudinal gradient and grouped them into functional feeding groups (FFGs). The results revealed that gatherers and filterers dominated in the Kowie River, and together represented 50 – 83% of the invertebrate assemblages. There was a general paucity of shredders (relative abundance was ≤ 10% across all sites and seasons). The changes in relative abundances of different FFGs did not follow predictions of the RCC along the longitudinal gradient, as there were no correlations of community structure with some physical attributes (stream width, canopy cover, distance of river) that changed along the river continuum. However, FFG abundances were related to water velocity, total dissolved solids and canopy cover. Broadly, the Kowie River data showed that changes in relative abundances of FFGs along the river continuum could not be explained by changes in physical attributes alone, and may be highly influenced by the availability of food and the chemistry of the stream. Analysis of stable carbon (δ13C) and nitrogen (δ15N) isotopes was used to estimate the contributions of algal and land-based production to consumers over space (six sites) and time (November 2012 to September 2013). Carbon contributions determined by the use of mixing models (Stable Isotope Analysis in R) revealed that consumers in the headwater assimilated mainly terrestrially-derived organic matter, with consumers in the middle and lower reaches assimilating autochthonous basal resources (macrophytes and algae). The findings from this river supported aspects of the RCC (at the headwaters; terrestrial organic matter made up 41% of consumer diets), but overall the data supported the predictions of the RPM (local production made the highest contributions of 50 – 86% to all FFGs across all seasons). The carbon isotopes of consumers and their food sources changed substantially every season, indicating that samples of food sources and consumers should be analysed many times throughout the year to capture that variability and to ensure that ephemeral components of the food web are not missed. To validate the findings from the isotope data, fatty acids were used as complementary tracers to determine the contributions of algal versus terrestrial organic matter to the consumers. Fatty acid tracers for terrestrial (Ʃω3/Ʃω6; 18:2ω6; 18:3ω3) vs aquatic (Ʃω3/Ʃω6; 20:5ω3) sources corroborated the findings from the isotope data set, as the mean ratio of Ʃω3/Ʃω6 in consumers was less than one at the headwaters (indicating allochthony), while middle and lower reaches were associated with Ʃω3/Ʃω6 > 1 (indicating autochthony). In addition to the tracer and FFG analyses for examining trophic connections between land and river, the bidirectional exchange of organisms between the riparian zone and the river was assessed using floating pyramidal traps (to measure emergence) and pan traps (for infalling invertebrates) placed at different sites in the river and the biomass in each trap was determined. The exchanges were variable over space and time, with emergence peaking in summer (169 to 1402 mg m-2 day-1) and declining in winter (3 to 28 mg m-2 day-1). Similarly, infalling invertebrates increased in summer (413 to 679 mg m-2 day-1) and declined in winter (11 to 220 mg m-2 day-1). Biomass measurements are indications of quantity that ignore nutritional quality, so I determined the bidirectional flow of invertebrates using absolute concentrations of physiologically important biochemical compounds (essential and polyunsaturated fatty acids). The fluxes of emergent and infalling arthropods peaked in summer (emergence = 0.3 to 18 mg m-2 day-1 and terrestrial infall = 0.3 to 3 mg m-2 day-1) and declined in winter (emergence = 0.01 to 0.51 mg m-2 day-1 and terrestrial infall = 0.01 to 0.03 mg m-2 day-1). However, during some seasons, no significant differences in polyunsaturated fatty acid flux in either direction were observed; this finding indicated the balance of reciprocal subsidisation via reciprocal flows of animals. Factors such as air temperature and algal productivity affected the reciprocal flows between adjacent habitats, with algal productivity being positively related to emergence while air temperature was positively correlated to infalling terrestrial invertebrates. This research enhances the growing body of literature on the function of riverine systems and offers some invaluable information on the flow of energy and the role played by invertebrates in translocating nutrients from terrestrial systems to aquatic systems and vice versa. This study unifies the concepts of the RCC and RPM and shows that these concepts are not limited only to large rivers, but are applicable to small southern temperate rivers too. However, some tenets of the theoretical models were challenged. For example, it challenges the proposition by the RCC that the fine particulate organic matter leaked from upstream breakdown of coarse particulate organic matter is predominantly allochthonous. Additionally, this study showed that in the headwaters, the RPM underestimated the role of autochthony. Overall, the results showed that the Kowie River and its riparian area are intrinsically connected. Once we understand the mechanisms controlling connections and subsidies across ecotones, we can then start to predict the consequences of disruptions to these connections by climate change and/or land use changes. To make predictions about future perturbations to rivers and riparian zones, studies like this, which considers the form and magnitude of subsidies, are needed to provide baseline information. Algal resources (e.g. epiphyton), macrophytes, riparian plants, terrestrial organisms and aquatic organisms all contributed to aquatic and terrestrial linkages in the Kowie River; therefore, it is important to conserve the different components of these ecosystems.
- Full Text:
- Date Issued: 2016
Are people responsive to a more sustainable, decentralized, and user-driven management of urban metabolism?:
- Chelleri, Lorenzo, Kua, Harn W, Rodriguez Sanchez, Juan P, Nahiduzzaman, Kh M, Thondhlana, Gladman
- Authors: Chelleri, Lorenzo , Kua, Harn W , Rodriguez Sanchez, Juan P , Nahiduzzaman, Kh M , Thondhlana, Gladman
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144299 , vital:38329 , https://orcid.org/0000-0001-8253-0264
- Description: Smart, green, and resilient city paradigms have been mainly promoted through top-down and technocratic approaches. However, based on the notion to return to “the right to the city”, emerging community-driven initiatives are providing self-managed infrastructures contributing to urban sustainability transitions. This paper explores the relevance of the behavioral aspects of people-centered approaches in dealing with two different facets of urban metabolism: physical infrastructure (involvement with the management of decentralized infrastructures) and consumption patterns (involvement in proactive reduction of resources used). In the first case we assessed community perceptions about the roles, benefits, and willingness to proactively engage in the management of decentralized green infrastructures in Bogotá City, Colombia. For the second facet, we measured the effectiveness of change agents in re-shaping energy consumption decisions within urban social networks in South Africa and Saudi Arabia. This paper’s results show that pre-determined and standardized strategies do not guarantee positive, nor homogeneous, results in terms of meeting sustainability targets, or promoting community involvement. Hence, a better integration of people-centered and top-down approaches is needed through context-dependent policies, for enhancing both users’ appreciation of and commitment to urban metabolism participative management.
- Full Text:
- Date Issued: 2016
- Authors: Chelleri, Lorenzo , Kua, Harn W , Rodriguez Sanchez, Juan P , Nahiduzzaman, Kh M , Thondhlana, Gladman
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144299 , vital:38329 , https://orcid.org/0000-0001-8253-0264
- Description: Smart, green, and resilient city paradigms have been mainly promoted through top-down and technocratic approaches. However, based on the notion to return to “the right to the city”, emerging community-driven initiatives are providing self-managed infrastructures contributing to urban sustainability transitions. This paper explores the relevance of the behavioral aspects of people-centered approaches in dealing with two different facets of urban metabolism: physical infrastructure (involvement with the management of decentralized infrastructures) and consumption patterns (involvement in proactive reduction of resources used). In the first case we assessed community perceptions about the roles, benefits, and willingness to proactively engage in the management of decentralized green infrastructures in Bogotá City, Colombia. For the second facet, we measured the effectiveness of change agents in re-shaping energy consumption decisions within urban social networks in South Africa and Saudi Arabia. This paper’s results show that pre-determined and standardized strategies do not guarantee positive, nor homogeneous, results in terms of meeting sustainability targets, or promoting community involvement. Hence, a better integration of people-centered and top-down approaches is needed through context-dependent policies, for enhancing both users’ appreciation of and commitment to urban metabolism participative management.
- Full Text:
- Date Issued: 2016
Art investment in South Africa: portfolio diversification and art market efficiency
- Botha, Ferdi, Snowball, Jeanette D, Scott, Brett
- Authors: Botha, Ferdi , Snowball, Jeanette D , Scott, Brett
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64794 , vital:28601 , http://www.dx.doi.org/10.17159/2222-3436/2016/v19n3a4
- Description: Art has been suggested as a good way to diversify investment portfolios during times of financial uncertainty. The argument is that art exhibits different risk and return characteristics to conventional investments in other asset classes. The new Citadel art price index offered the opportunity to test this theory in the South African context. Moreover, this paper tests whether art prices are efficient. The Citadel index uses the hedonic regression method with observations drawn from the top 100, 50 and 20 artists by sales volume, giving approximately 29 503 total auction observations. The Index consists of quarterly data from the period 2000Q1 to 2013Q3. A vector autoregression of the art price index, Johannesburg stock exchange all-share index, house price index, and South African government bond index were used. Results show that, when there are increased returns on the stock market in a preceding period and wealth increases, there is a change in the Citadel art price index in the same direction. No significant difference was found between the house price index and the art price index, or between the art and government bond price indices. The art market is also found to be inefficient, thereby exacerbating the risk of investing in art. Overall, the South African art market does not offer the opportunity to diversify portfolios dominated by either property, bonds, or shares.
- Full Text:
- Date Issued: 2016
- Authors: Botha, Ferdi , Snowball, Jeanette D , Scott, Brett
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/64794 , vital:28601 , http://www.dx.doi.org/10.17159/2222-3436/2016/v19n3a4
- Description: Art has been suggested as a good way to diversify investment portfolios during times of financial uncertainty. The argument is that art exhibits different risk and return characteristics to conventional investments in other asset classes. The new Citadel art price index offered the opportunity to test this theory in the South African context. Moreover, this paper tests whether art prices are efficient. The Citadel index uses the hedonic regression method with observations drawn from the top 100, 50 and 20 artists by sales volume, giving approximately 29 503 total auction observations. The Index consists of quarterly data from the period 2000Q1 to 2013Q3. A vector autoregression of the art price index, Johannesburg stock exchange all-share index, house price index, and South African government bond index were used. Results show that, when there are increased returns on the stock market in a preceding period and wealth increases, there is a change in the Citadel art price index in the same direction. No significant difference was found between the house price index and the art price index, or between the art and government bond price indices. The art market is also found to be inefficient, thereby exacerbating the risk of investing in art. Overall, the South African art market does not offer the opportunity to diversify portfolios dominated by either property, bonds, or shares.
- Full Text:
- Date Issued: 2016
Assessing authentic leadership and workplace trust amongst managerial government employees in Lesotho
- Authors: Damane, Likeleko
- Date: 2016
- Subjects: Leadership -- Moral and ethical aspects , Industrial management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/9033 , vital:26458
- Description: In today‘s world, characterised by highly competitive global economies, organisations have realised the need for a positive approach in order to remain competitive, sustainable and to attract and retain talent. A positive approach to leadership and an organisational environment characterised by trust has been one of the fundamental tools towards achieving this goal. The main objective of the present study was to assess the existence of positive organizational approaches (authentic leadership and workplace trust) within the government of Lesotho, especially at a time when the country was facing difficulties. The study was descriptive in nature, and followed a non-experimental quantitative approach. The survey made use of a sample of 153 civil servants occupying positions from supervisory to senior management. Data was acquired through the use of an electronic questionnaire made up of two scales: one was a self-assessment instrument on authentic leadership adopted from Walumbwa and associates, and the other scale was on workplace trust developed by Natalie Ferres. The analysis of data involved descriptive statistics, t-tests, ANOVA, post hoc tests and Cohen‘s d. The results of the study provided evidence that there were high levels of the authentic leadership and trust in the workplace. Demographic variables were not found to influence the outcome of authentic leadership scores, however, education and managerial level were found to have an influence on organisational trust. The findings of the study provoked the researcher to call for an implementation of policy on positive training for management and for further research in this area.
- Full Text:
- Date Issued: 2016
- Authors: Damane, Likeleko
- Date: 2016
- Subjects: Leadership -- Moral and ethical aspects , Industrial management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/9033 , vital:26458
- Description: In today‘s world, characterised by highly competitive global economies, organisations have realised the need for a positive approach in order to remain competitive, sustainable and to attract and retain talent. A positive approach to leadership and an organisational environment characterised by trust has been one of the fundamental tools towards achieving this goal. The main objective of the present study was to assess the existence of positive organizational approaches (authentic leadership and workplace trust) within the government of Lesotho, especially at a time when the country was facing difficulties. The study was descriptive in nature, and followed a non-experimental quantitative approach. The survey made use of a sample of 153 civil servants occupying positions from supervisory to senior management. Data was acquired through the use of an electronic questionnaire made up of two scales: one was a self-assessment instrument on authentic leadership adopted from Walumbwa and associates, and the other scale was on workplace trust developed by Natalie Ferres. The analysis of data involved descriptive statistics, t-tests, ANOVA, post hoc tests and Cohen‘s d. The results of the study provided evidence that there were high levels of the authentic leadership and trust in the workplace. Demographic variables were not found to influence the outcome of authentic leadership scores, however, education and managerial level were found to have an influence on organisational trust. The findings of the study provoked the researcher to call for an implementation of policy on positive training for management and for further research in this area.
- Full Text:
- Date Issued: 2016
Assessing estuarine nursery habitats for Cape Stumpnose (Rhabdosargus holubi), (Pisces: Sparidae) in a warm-temperate estuary in the Eastern Cape, South Africa
- Authors: Leslie, Timothy David
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3178 , vital:20381
- Description: The nursery role hypothesis provides an approach for assessing the nursery function of habitat types within estuaries. This study attempted to assess the nursery value of the dominant estuarine habitats in the Bushmans Estuary for Rhabdosargus holubi (Steindachner 1881) by analysing habitat complexity, relative abundance and behaviour of R. holubi and using stomach contents analysis and dietary diatom composition as indicative of feeding habitat. Structural habitat complexity was assessed in Zostera capensis (Setchell) seagrass and Spartina maritima (Curtis Fernald) salt marsh by sampling above-ground stem density and length, and total cover per unit area (Ct/At). Dimensionless habitat complexity indices such as the interstitial spatial index (ISI) at three magnifications and fractal geometry at two magnifications were used to further analyse habitat complexity. Above-ground biomass (P<0.05) in each season and canopy height (P<0.001) were significantly higher in salt marsh than in seagrass whilst stem density was significantly higher in seagrass than in salt marsh in each season (P<0.001). Each dimensionless index indicated that complexity is notably higher in seagrass than in the salt marsh. Using dimensionless indices that analyse complexity at different spatial scales provided a better analysis of habitat complexity than canopy height and biomass as it allowed for direct comparisons between habitat types. Underwater video cameras were deployed in seagrass, salt marsh and sand flat habitats to assess the relative abundance and behaviour of R. holubi. The relative abundance of R. holubi was significantly higher in seagrass than salt marsh and sand flats, whilst the behaviour of R. holubi indicated a high degree of habitat use in structured habitats and a low degree of habitat use in unstructured sand flat habitats. This indicated that not only are juvenile R. holubi a vegetation-associated species, but also a species that prefers seagrass to salt marsh.
- Full Text:
- Date Issued: 2016
- Authors: Leslie, Timothy David
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3178 , vital:20381
- Description: The nursery role hypothesis provides an approach for assessing the nursery function of habitat types within estuaries. This study attempted to assess the nursery value of the dominant estuarine habitats in the Bushmans Estuary for Rhabdosargus holubi (Steindachner 1881) by analysing habitat complexity, relative abundance and behaviour of R. holubi and using stomach contents analysis and dietary diatom composition as indicative of feeding habitat. Structural habitat complexity was assessed in Zostera capensis (Setchell) seagrass and Spartina maritima (Curtis Fernald) salt marsh by sampling above-ground stem density and length, and total cover per unit area (Ct/At). Dimensionless habitat complexity indices such as the interstitial spatial index (ISI) at three magnifications and fractal geometry at two magnifications were used to further analyse habitat complexity. Above-ground biomass (P<0.05) in each season and canopy height (P<0.001) were significantly higher in salt marsh than in seagrass whilst stem density was significantly higher in seagrass than in salt marsh in each season (P<0.001). Each dimensionless index indicated that complexity is notably higher in seagrass than in the salt marsh. Using dimensionless indices that analyse complexity at different spatial scales provided a better analysis of habitat complexity than canopy height and biomass as it allowed for direct comparisons between habitat types. Underwater video cameras were deployed in seagrass, salt marsh and sand flat habitats to assess the relative abundance and behaviour of R. holubi. The relative abundance of R. holubi was significantly higher in seagrass than salt marsh and sand flats, whilst the behaviour of R. holubi indicated a high degree of habitat use in structured habitats and a low degree of habitat use in unstructured sand flat habitats. This indicated that not only are juvenile R. holubi a vegetation-associated species, but also a species that prefers seagrass to salt marsh.
- Full Text:
- Date Issued: 2016
Assessing Nelson Mandela Bay Municipality's urban resilience
- Authors: Gatang'i, Rebecca Nyangige
- Date: 2016
- Subjects: Sustainable development -- South Africa -- Nelson Mandela Bay Municipality , City planning -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/7637 , vital:22273
- Description: The quest for resilient cities has emerged as a strategy to mitigate and adapt the problems created by urban population growth and rapid urbanisation. Resilience has increasingly become an important urban policy discourse that challenge cities to reflect on their adaptive capacity to function in the face of adversity. Urban resilience in particular, amplifies the concern that urban spaces are the hub of heightened complexities of diverse risks. Across the globe, the concept of resilience is gaining momentum with many academic researchers discussing this phenomenon. In South Africa, the concept has been sparingly incorporated in a number of literatures with little focus on local government entities such as municipalities. In order to close this gap in the literature, and in response to the increasing use of the concept locally, this study explores the extent to which factors of resilience resonate within the Nelson Mandela Bay Municipality urban management practices. Based on the exploration of a wide array of literature from various disciplinary areas, this study examines the concept of urbanisation and the related challenges. It also critically explores the concept of resilience, its application in urban management as well as the attributes of the adaptive capacities that enable urban resilience. This research adopts the City Resilience Framework and Index developed by Arup in partnership with the Rockefeller Foundation to assess the levels of resilience in the Nelson Mandela Bay Municipality. The framework identifies four main dimensions used to measure resilience: People’s health and wellbeing, Organisation of the economy and society, Place of urban systems and services and Knowledge inherent in leadership and strategy. These dimensions form the basis of an integrative framework that provides an alternative lense through which cities can understand their unique attributes that contribute to their resilience. This research highlights the levels of resilience within the Nelson Mandela Bay Municipality and outlines practical implications for Nelson Mandela Bay Municipality’s management which can also be applied in other cities. This research adopts a positivist approach and applies statistical empirical measures using a quantitative analysis process. The research instrument in the form of a questionnaire was administered to the target population for data collection. Using the conceptual framework, the researcher applied statistical analysis to derive relationships amongst the variables to determine the degree of resilience in Nelson Mandela Bay Municipality using the four main dimensions of the framework. The findings of the study show the varying levels of resilience within NMBM’s practices. NMBM’s principal success areas include; providing basic houses, ensuring water and sanitation facilities, instituting effective labour policies, providing skills development and training facilities especially to the youth, enabling a conducive atmosphere for business development and the presence of an integrated development strategy. However, not much has been done in providing sufficient public health facilities, alternative energy sources, access to financial services, ensuring food security, enabling continuity of projects and activities through a funded budget, providing emergency medical services in the event of a disaster, high levels of corruption and insufficient deterrents to crime. Overall, the results show that NMBM has made good strides in enabling high level of resilience in its day to day operations. The findings of this study suggest that urban resilience is a continuous process that facilitates engagement leading to a dialogue and deeper understanding of a city.
- Full Text:
- Date Issued: 2016
- Authors: Gatang'i, Rebecca Nyangige
- Date: 2016
- Subjects: Sustainable development -- South Africa -- Nelson Mandela Bay Municipality , City planning -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/7637 , vital:22273
- Description: The quest for resilient cities has emerged as a strategy to mitigate and adapt the problems created by urban population growth and rapid urbanisation. Resilience has increasingly become an important urban policy discourse that challenge cities to reflect on their adaptive capacity to function in the face of adversity. Urban resilience in particular, amplifies the concern that urban spaces are the hub of heightened complexities of diverse risks. Across the globe, the concept of resilience is gaining momentum with many academic researchers discussing this phenomenon. In South Africa, the concept has been sparingly incorporated in a number of literatures with little focus on local government entities such as municipalities. In order to close this gap in the literature, and in response to the increasing use of the concept locally, this study explores the extent to which factors of resilience resonate within the Nelson Mandela Bay Municipality urban management practices. Based on the exploration of a wide array of literature from various disciplinary areas, this study examines the concept of urbanisation and the related challenges. It also critically explores the concept of resilience, its application in urban management as well as the attributes of the adaptive capacities that enable urban resilience. This research adopts the City Resilience Framework and Index developed by Arup in partnership with the Rockefeller Foundation to assess the levels of resilience in the Nelson Mandela Bay Municipality. The framework identifies four main dimensions used to measure resilience: People’s health and wellbeing, Organisation of the economy and society, Place of urban systems and services and Knowledge inherent in leadership and strategy. These dimensions form the basis of an integrative framework that provides an alternative lense through which cities can understand their unique attributes that contribute to their resilience. This research highlights the levels of resilience within the Nelson Mandela Bay Municipality and outlines practical implications for Nelson Mandela Bay Municipality’s management which can also be applied in other cities. This research adopts a positivist approach and applies statistical empirical measures using a quantitative analysis process. The research instrument in the form of a questionnaire was administered to the target population for data collection. Using the conceptual framework, the researcher applied statistical analysis to derive relationships amongst the variables to determine the degree of resilience in Nelson Mandela Bay Municipality using the four main dimensions of the framework. The findings of the study show the varying levels of resilience within NMBM’s practices. NMBM’s principal success areas include; providing basic houses, ensuring water and sanitation facilities, instituting effective labour policies, providing skills development and training facilities especially to the youth, enabling a conducive atmosphere for business development and the presence of an integrated development strategy. However, not much has been done in providing sufficient public health facilities, alternative energy sources, access to financial services, ensuring food security, enabling continuity of projects and activities through a funded budget, providing emergency medical services in the event of a disaster, high levels of corruption and insufficient deterrents to crime. Overall, the results show that NMBM has made good strides in enabling high level of resilience in its day to day operations. The findings of this study suggest that urban resilience is a continuous process that facilitates engagement leading to a dialogue and deeper understanding of a city.
- Full Text:
- Date Issued: 2016
Assessing Nelson Mandela Bay Municipality's urban resilience
- Authors: Gatang'i, Rebecca Nyangige
- Date: 2016
- Subjects: City planning -- South Africa -- Nelson Mandela Bay Municipality , Sustainable development -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/7639 , vital:22272
- Description: The quest for resilient cities has emerged as a strategy to mitigate and adapt the problems created by urban population growth and rapid urbanisation. Resilience has increasingly become an important urban policy discourse that challenge cities to reflect on their adaptive capacity to function in the face of adversity. Urban resilience in particular, amplifies the concern that urban spaces are the hub of heightened complexities of diverse risks. Across the globe, the concept of resilience is gaining momentum with many academic researchers discussing this phenomenon. In South Africa, the concept has been sparingly incorporated in a number of literatures with little focus on local government entities such as municipalities. In order to close this gap in the literature, and in response to the increasing use of the concept locally, this study explores the extent to which factors of resilience resonate within the Nelson Mandela Bay Municipality urban management practices. Based on the exploration of a wide array of literature from various disciplinary areas, this study examines the concept of urbanisation and the related challenges. It also critically explores the concept of resilience, its application in urban management as well as the attributes of the adaptive capacities that enable urban resilience. This research adopts the City Resilience Framework and Index developed by Arup in partnership with the Rockefeller Foundation to assess the levels of resilience in the Nelson Mandela Bay Municipality. The framework identifies four main dimensions used to measure resilience: People’s health and wellbeing, Organisation of the economy and society, Place of urban systems and services and Knowledge inherent in leadership and strategy. These dimensions form the basis of an integrative framework that provides an alternative lense through which cities can understand their unique attributes that contribute to their resilience. This research highlights the levels of resilience within the Nelson Mandela Bay Municipality and outlines practical implications for Nelson Mandela Bay Municipality’s management which can also be applied in other cities. This research adopts a positivist approach and applies statistical empirical measures using a quantitative analysis process. The research instrument in the form of a questionnaire was administered to the target population for data collection. Using the conceptual framework, the researcher applied statistical analysis to derive relationships amongst the variables to determine the degree of resilience in Nelson Mandela Bay Municipality using the four main dimensions of the framework. The findings of the study show the varying levels of resilience within NMBM’s practices. NMBM’s principal success areas include; providing basic houses, ensuring water and sanitation facilities, instituting effective labour policies, providing skills development and training facilities especially to the youth, enabling a conducive atmosphere for business development and the presence of an integrated development strategy. However, not much has been done in providing sufficient public health facilities, alternative energy sources, access to financial services, ensuring food security, enabling continuity of projects and activities through a funded budget, providing emergency medical services in the event of a disaster, high levels of corruption and insufficient deterrents to crime. Overall, the results show that NMBM has made good strides in enabling high level of resilience in its day to day operations. The findings of this study suggest that urban resilience is a continuous process that facilitates engagement leading to a dialogue and deeper understanding of a city.
- Full Text:
- Date Issued: 2016
- Authors: Gatang'i, Rebecca Nyangige
- Date: 2016
- Subjects: City planning -- South Africa -- Nelson Mandela Bay Municipality , Sustainable development -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/7639 , vital:22272
- Description: The quest for resilient cities has emerged as a strategy to mitigate and adapt the problems created by urban population growth and rapid urbanisation. Resilience has increasingly become an important urban policy discourse that challenge cities to reflect on their adaptive capacity to function in the face of adversity. Urban resilience in particular, amplifies the concern that urban spaces are the hub of heightened complexities of diverse risks. Across the globe, the concept of resilience is gaining momentum with many academic researchers discussing this phenomenon. In South Africa, the concept has been sparingly incorporated in a number of literatures with little focus on local government entities such as municipalities. In order to close this gap in the literature, and in response to the increasing use of the concept locally, this study explores the extent to which factors of resilience resonate within the Nelson Mandela Bay Municipality urban management practices. Based on the exploration of a wide array of literature from various disciplinary areas, this study examines the concept of urbanisation and the related challenges. It also critically explores the concept of resilience, its application in urban management as well as the attributes of the adaptive capacities that enable urban resilience. This research adopts the City Resilience Framework and Index developed by Arup in partnership with the Rockefeller Foundation to assess the levels of resilience in the Nelson Mandela Bay Municipality. The framework identifies four main dimensions used to measure resilience: People’s health and wellbeing, Organisation of the economy and society, Place of urban systems and services and Knowledge inherent in leadership and strategy. These dimensions form the basis of an integrative framework that provides an alternative lense through which cities can understand their unique attributes that contribute to their resilience. This research highlights the levels of resilience within the Nelson Mandela Bay Municipality and outlines practical implications for Nelson Mandela Bay Municipality’s management which can also be applied in other cities. This research adopts a positivist approach and applies statistical empirical measures using a quantitative analysis process. The research instrument in the form of a questionnaire was administered to the target population for data collection. Using the conceptual framework, the researcher applied statistical analysis to derive relationships amongst the variables to determine the degree of resilience in Nelson Mandela Bay Municipality using the four main dimensions of the framework. The findings of the study show the varying levels of resilience within NMBM’s practices. NMBM’s principal success areas include; providing basic houses, ensuring water and sanitation facilities, instituting effective labour policies, providing skills development and training facilities especially to the youth, enabling a conducive atmosphere for business development and the presence of an integrated development strategy. However, not much has been done in providing sufficient public health facilities, alternative energy sources, access to financial services, ensuring food security, enabling continuity of projects and activities through a funded budget, providing emergency medical services in the event of a disaster, high levels of corruption and insufficient deterrents to crime. Overall, the results show that NMBM has made good strides in enabling high level of resilience in its day to day operations. The findings of this study suggest that urban resilience is a continuous process that facilitates engagement leading to a dialogue and deeper understanding of a city.
- Full Text:
- Date Issued: 2016
Assessing the effect of absenteeism in the Eastern Cape Department of Health
- Authors: Simon, Nobuzwe
- Date: 2016
- Subjects: Absenteeism (Labor) , Public health personnel , Absenteeism (Labor) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2271 , vital:27736
- Description: The Department of Health is experiencing repeated negative press releases with the respect to the quality of service delivery in the Eastern Cape. The public sector is an entity that provides a unique service. This is made evident by the services provided such as provision of free health services for primary health care as well as free health services to children under six, disabled and senior citizens. The Eastern Cape Department of Health has developed service standards adopted in 2007 by the Eastern Cape Department of Health. This study aims to determine the casual effect of absenteeism and their relationship to poor service delivery. According to Makhubu (2006) many vacancies in the Eastern Cape Department of Health exist which result in service delivery problems. In terms of the second principle in the Batho Pele Principles the norms and standards which are service standards serves as a baseline where the Department of Public Service and Administration (2007) issued directive that the vacancy rate of any government department should range between ten and fifteen percent Makhubu (2006) further refers to the doctors/patient ratio as one is to three hundred patients (1:300), which is unhealthy and abnormal as the doctor/patient ration in terms of the Health Professional is one is to thirty (1:30). Such cases pose an opportunity to those employees who are within the service to absent themselves from such unhealthy situations and this behavior later result in the exodus (professional drainage) of employee. Schultz, Nel, Gerber, Hassbroek, Van Dyk and Werner (2001:582) define absenteeism as withdrawal of levels of productivity and collegial interaction for a given time to escape a perceived undesirable working environment. This behavior is disruptive to continuous organizational efficiency. Absenteeism is found in two forms that are avoidable and unavoidable. In the unavoidable forms of absenteeism, the situation in unplanned and is governed by external factors, thus it is beyond one’s control and has to be managed differently. Control of absenteeism can exercise by the immediate manager through the human resource section regarding the duration and terms of absence pertaining salary and terms of services.
- Full Text:
- Date Issued: 2016
- Authors: Simon, Nobuzwe
- Date: 2016
- Subjects: Absenteeism (Labor) , Public health personnel , Absenteeism (Labor) -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2271 , vital:27736
- Description: The Department of Health is experiencing repeated negative press releases with the respect to the quality of service delivery in the Eastern Cape. The public sector is an entity that provides a unique service. This is made evident by the services provided such as provision of free health services for primary health care as well as free health services to children under six, disabled and senior citizens. The Eastern Cape Department of Health has developed service standards adopted in 2007 by the Eastern Cape Department of Health. This study aims to determine the casual effect of absenteeism and their relationship to poor service delivery. According to Makhubu (2006) many vacancies in the Eastern Cape Department of Health exist which result in service delivery problems. In terms of the second principle in the Batho Pele Principles the norms and standards which are service standards serves as a baseline where the Department of Public Service and Administration (2007) issued directive that the vacancy rate of any government department should range between ten and fifteen percent Makhubu (2006) further refers to the doctors/patient ratio as one is to three hundred patients (1:300), which is unhealthy and abnormal as the doctor/patient ration in terms of the Health Professional is one is to thirty (1:30). Such cases pose an opportunity to those employees who are within the service to absent themselves from such unhealthy situations and this behavior later result in the exodus (professional drainage) of employee. Schultz, Nel, Gerber, Hassbroek, Van Dyk and Werner (2001:582) define absenteeism as withdrawal of levels of productivity and collegial interaction for a given time to escape a perceived undesirable working environment. This behavior is disruptive to continuous organizational efficiency. Absenteeism is found in two forms that are avoidable and unavoidable. In the unavoidable forms of absenteeism, the situation in unplanned and is governed by external factors, thus it is beyond one’s control and has to be managed differently. Control of absenteeism can exercise by the immediate manager through the human resource section regarding the duration and terms of absence pertaining salary and terms of services.
- Full Text:
- Date Issued: 2016
Assessing the impact of climate change on mangrove crabs: the role of ontogenetic macrophysiology and settlement in the persistence of central and marginal populations
- Authors: Mostert, Bruce Petrus
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/826 , vital:19994
- Description: After a brief respite in the mid to late 20th century, macro physiology has come to the fore in elucidating large scale ecological patterns and processes as physiological assumptions often form the backbone of many predictive theories associated with species distributions. Critically, macro physiological patterns are valuable in explaining physiological variation across multiple scales and provide insights into the effects of climate change on populations spanning a wide range of latitudes. This can assist in predicting possible distribution expansions, contractions or shifts in light of current climate change scenarios. From this perspective, investigating intra- and inter-specific physiological responses to environmental stress may contribute to better understanding and predicting the effects of climate change on geographical ranges. Further, investigating the physiological effects to environmental stresses across ontogenetic stages allows for the identification of weak links within the lifecycle of a species. Additionally, determining settlement characteristics along a latitudinal cline provides integrated indications of the sustainability of populations, highlighting vulnerable regions in terms of repopulation of viable habitats. In this context, the present study aimed at establishing how temperature, in a physiological context, may affect reproductive biology of two species of mangrove crab, Perisesarma guttatum and Uca urvillei at the centre (Kenya) and edge (South Africa) of their distributional range along the east coast of Africa and highlight possible consequences for range distributions. A third species, Neosarmatium africanum, only in South Africa, was included to provide additional interspecies comparisons. Furthermore, settlement characteristics of brachyuran populations at the centre and edge of their distributional range were considered in order to determine how settlement may contribute to population persistence. Physiological investigations at the centre and edge of distributional range and across ontogenetic stages (larvae, stage 2 and 4 embryos, non-gravid and gravid females) under the concept of oxygen and capacity limitation of thermal tolerance (OCLTT), revealed that, for both species, populations at the centre of their distribution (Kenya) were generally more robust to increasing temperatures and generally displayed greater physiological stability with increasing temperatures compared to their conspecifics in South Africa. Variability in physiological robustness between regions, did however, differ among ontogenetic stages and species but, overall, were evident throughout. Within and between regions, adaptation to oxygen extraction in both milieus (air or water) was displayed for present temperature conditions but aerial respiration largely alleviated increased thermal stress due to overcoming the limitations of reduced oxygen availability and diffusiveness in water for all bimodal ontogenetic stages. Brooding eggs proved to be a physiologically critical process with either heighted oxygen consumption for gravid females or collapse of physiological processes demonstrated by supressed oxygen consumption. The physiological cost of brooding eggs, referred to as maternal costs, was reflected in in both Perisesarma guttatum and Uca urvillei where, in most cases, maternal costs were negative. Again, aerial respiration was able to alleviated increased thermal stress, as shown by positive maternal costs indicating sustained maternal care, but this mechanism was species and regionally specific. Settlement patterns differed between the edge and centre of distribution of the species studied. This difference was predominantly driven by zonal preference within the mangal and/or effects of new and full moon (lunar phase). Overall, settlement dynamics were more widely variable in South Africa, both spatially and temporally, than in Kenya. Finally, empirical physiological data from ontogenetic stages present during the reproductive process (early and late stage embryos) and from non-gravid and gravid females were used in conjunction with data mined from the existing literature to parameterise an individual based model designed to simulate reproductive output at the centre and edge of distribution of Perisesarma guttatum. Physiological data indicate that, in terms of reproductive output across increasing temperatures, populations based at the centre of their distribution presently outperform their counterparts at the edge of the species’ distribution, but reproductive output stagnated as temperature rose. Edge of distribution populations consistently increased reproductive output with increasing temperatures to eventually outperform centre of distribution populations at higher simulated temperatures. Overall, results of the physiological and settlement studies suggest that with increased climate change there may be a contraction of distributional range of the study species from high latitudes to low latitudes, contrary to general poleward shifts/migrations seen in most species, with possible contractions of the entire ecosystem mirroring the disappearance of keystone mangrove macrofauna.
- Full Text:
- Date Issued: 2016
- Authors: Mostert, Bruce Petrus
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/826 , vital:19994
- Description: After a brief respite in the mid to late 20th century, macro physiology has come to the fore in elucidating large scale ecological patterns and processes as physiological assumptions often form the backbone of many predictive theories associated with species distributions. Critically, macro physiological patterns are valuable in explaining physiological variation across multiple scales and provide insights into the effects of climate change on populations spanning a wide range of latitudes. This can assist in predicting possible distribution expansions, contractions or shifts in light of current climate change scenarios. From this perspective, investigating intra- and inter-specific physiological responses to environmental stress may contribute to better understanding and predicting the effects of climate change on geographical ranges. Further, investigating the physiological effects to environmental stresses across ontogenetic stages allows for the identification of weak links within the lifecycle of a species. Additionally, determining settlement characteristics along a latitudinal cline provides integrated indications of the sustainability of populations, highlighting vulnerable regions in terms of repopulation of viable habitats. In this context, the present study aimed at establishing how temperature, in a physiological context, may affect reproductive biology of two species of mangrove crab, Perisesarma guttatum and Uca urvillei at the centre (Kenya) and edge (South Africa) of their distributional range along the east coast of Africa and highlight possible consequences for range distributions. A third species, Neosarmatium africanum, only in South Africa, was included to provide additional interspecies comparisons. Furthermore, settlement characteristics of brachyuran populations at the centre and edge of their distributional range were considered in order to determine how settlement may contribute to population persistence. Physiological investigations at the centre and edge of distributional range and across ontogenetic stages (larvae, stage 2 and 4 embryos, non-gravid and gravid females) under the concept of oxygen and capacity limitation of thermal tolerance (OCLTT), revealed that, for both species, populations at the centre of their distribution (Kenya) were generally more robust to increasing temperatures and generally displayed greater physiological stability with increasing temperatures compared to their conspecifics in South Africa. Variability in physiological robustness between regions, did however, differ among ontogenetic stages and species but, overall, were evident throughout. Within and between regions, adaptation to oxygen extraction in both milieus (air or water) was displayed for present temperature conditions but aerial respiration largely alleviated increased thermal stress due to overcoming the limitations of reduced oxygen availability and diffusiveness in water for all bimodal ontogenetic stages. Brooding eggs proved to be a physiologically critical process with either heighted oxygen consumption for gravid females or collapse of physiological processes demonstrated by supressed oxygen consumption. The physiological cost of brooding eggs, referred to as maternal costs, was reflected in in both Perisesarma guttatum and Uca urvillei where, in most cases, maternal costs were negative. Again, aerial respiration was able to alleviated increased thermal stress, as shown by positive maternal costs indicating sustained maternal care, but this mechanism was species and regionally specific. Settlement patterns differed between the edge and centre of distribution of the species studied. This difference was predominantly driven by zonal preference within the mangal and/or effects of new and full moon (lunar phase). Overall, settlement dynamics were more widely variable in South Africa, both spatially and temporally, than in Kenya. Finally, empirical physiological data from ontogenetic stages present during the reproductive process (early and late stage embryos) and from non-gravid and gravid females were used in conjunction with data mined from the existing literature to parameterise an individual based model designed to simulate reproductive output at the centre and edge of distribution of Perisesarma guttatum. Physiological data indicate that, in terms of reproductive output across increasing temperatures, populations based at the centre of their distribution presently outperform their counterparts at the edge of the species’ distribution, but reproductive output stagnated as temperature rose. Edge of distribution populations consistently increased reproductive output with increasing temperatures to eventually outperform centre of distribution populations at higher simulated temperatures. Overall, results of the physiological and settlement studies suggest that with increased climate change there may be a contraction of distributional range of the study species from high latitudes to low latitudes, contrary to general poleward shifts/migrations seen in most species, with possible contractions of the entire ecosystem mirroring the disappearance of keystone mangrove macrofauna.
- Full Text:
- Date Issued: 2016
Assessing the impacts of social grants on beneficiaries in Buffalo City Municipality
- Authors: Dodo, Emmanuel Oluwafemi
- Date: 2016
- Subjects: Social security -- South Africa -- Eastern Cape Grants-in-aid -- South Africa -- Eastern Cape Poor -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/2967 , vital:28206
- Description: The study was intended to assess the impact of social grants on beneficiaries with specific focus on Buffalo Municipality. The challenge of social injustice and inequality in the management and distribution of resources is challenge of any responsive government globally in providing social securities in different forms to secure the vulnerable and under privileged within the society. The South African government has introduced a comprehensive liberally inclusive social welfare scheme to address social injustice and economic inequality of excluded in the former apartheid government, which characterises the historic past of racial exclusive government of the majority black and the coloured. In other to assess the impact of grants in addressing inequality and social exclusiveness, the research was conducted using Desk Top Analytical approach and also explored ANOVA Two-ways and One-way, to test the degree of association and standard deviation to establish the contrast of effects based on spatial difference and social development of the urban, semi-urban and rural settlements which beneficiaries are living. Also, to establish whether or not the policy is achieving social cohesion, human development and transformation, which should be taken, place within the concept of social welfare. The theoretical frame work adopted is a multi-theoretical approach in dealing with the complexity around social welfare. The research is specifically looking for a theory of change in social grants administration in other to understand the impact and extent of the intervention in bringing about desired and motivated change as the scheme main priority of developmental social welfare in South Africa. Pearson correlation, Chi-square correlation and Tukey”s Post hoc Test are some of the instrument used in assessing the impact of grants on beneficiaries. The outcome of the study showed a highly significance p-value =.019, p<0.05 in spatial variance between Urban and Rural and the in between variance of .025, p<0.05 for Rural –Urban- Semi-urban (Fig.23 and Tab 8a). The study also, revealed an association between Child dependency and Sexual crime to be .009, p<0.01 (Fig 24 and Tab 6), Public violence in Rural area shows Post Hoc Test result of Mean= 2.6, SD= 2.07 for rural, Mean=1.40 SD= 1.52, for urban and a Mean=0.3, SD=0.54 for semi-urban in a descending order as it relate to social crime statistics (Fig.20). This implies that there are more frequent public violence in rural areas than that of the urban and semi-urban. The overall result shows a very strong correlation among all the variables of grants beneficiaries to be statistically relevant. This implies that the social grants intervention.
- Full Text:
- Date Issued: 2016
- Authors: Dodo, Emmanuel Oluwafemi
- Date: 2016
- Subjects: Social security -- South Africa -- Eastern Cape Grants-in-aid -- South Africa -- Eastern Cape Poor -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/2967 , vital:28206
- Description: The study was intended to assess the impact of social grants on beneficiaries with specific focus on Buffalo Municipality. The challenge of social injustice and inequality in the management and distribution of resources is challenge of any responsive government globally in providing social securities in different forms to secure the vulnerable and under privileged within the society. The South African government has introduced a comprehensive liberally inclusive social welfare scheme to address social injustice and economic inequality of excluded in the former apartheid government, which characterises the historic past of racial exclusive government of the majority black and the coloured. In other to assess the impact of grants in addressing inequality and social exclusiveness, the research was conducted using Desk Top Analytical approach and also explored ANOVA Two-ways and One-way, to test the degree of association and standard deviation to establish the contrast of effects based on spatial difference and social development of the urban, semi-urban and rural settlements which beneficiaries are living. Also, to establish whether or not the policy is achieving social cohesion, human development and transformation, which should be taken, place within the concept of social welfare. The theoretical frame work adopted is a multi-theoretical approach in dealing with the complexity around social welfare. The research is specifically looking for a theory of change in social grants administration in other to understand the impact and extent of the intervention in bringing about desired and motivated change as the scheme main priority of developmental social welfare in South Africa. Pearson correlation, Chi-square correlation and Tukey”s Post hoc Test are some of the instrument used in assessing the impact of grants on beneficiaries. The outcome of the study showed a highly significance p-value =.019, p<0.05 in spatial variance between Urban and Rural and the in between variance of .025, p<0.05 for Rural –Urban- Semi-urban (Fig.23 and Tab 8a). The study also, revealed an association between Child dependency and Sexual crime to be .009, p<0.01 (Fig 24 and Tab 6), Public violence in Rural area shows Post Hoc Test result of Mean= 2.6, SD= 2.07 for rural, Mean=1.40 SD= 1.52, for urban and a Mean=0.3, SD=0.54 for semi-urban in a descending order as it relate to social crime statistics (Fig.20). This implies that there are more frequent public violence in rural areas than that of the urban and semi-urban. The overall result shows a very strong correlation among all the variables of grants beneficiaries to be statistically relevant. This implies that the social grants intervention.
- Full Text:
- Date Issued: 2016
Assessing the productivity of selective container terminals in Africa using Data Envelopment Analysis (DEA)
- Mienie, Barend Jacobus, Brettenny, Warren
- Authors: Mienie, Barend Jacobus , Brettenny, Warren
- Date: 2016
- Subjects: Data envelopment analysis -- Africa Employees -- Rating of -- Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/12054 , vital:27026
- Description: Data envelopment analysis (DEA) is used to assess the efficiency of 15 container terminals in Africa. The models proposed by Charnes, Cooper and Rhodes (1978) and Banker, Charnes and Cooper (1984) are used to determine and rank the efficiencies of the container terminals for 2013 and 2014. The results show that selected South African container terminals can improve on their operations relative to some of their neighbours to the North. Bootstrapping methods are used to investigate and clarify the results. The Malmquist Productivity Index (MPI) model is used to track and explain changes in efficiency over the period of assessment.
- Full Text:
- Date Issued: 2016
- Authors: Mienie, Barend Jacobus , Brettenny, Warren
- Date: 2016
- Subjects: Data envelopment analysis -- Africa Employees -- Rating of -- Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10948/12054 , vital:27026
- Description: Data envelopment analysis (DEA) is used to assess the efficiency of 15 container terminals in Africa. The models proposed by Charnes, Cooper and Rhodes (1978) and Banker, Charnes and Cooper (1984) are used to determine and rank the efficiencies of the container terminals for 2013 and 2014. The results show that selected South African container terminals can improve on their operations relative to some of their neighbours to the North. Bootstrapping methods are used to investigate and clarify the results. The Malmquist Productivity Index (MPI) model is used to track and explain changes in efficiency over the period of assessment.
- Full Text:
- Date Issued: 2016
Assessing the risk factors of Coronary heart disease among rural adults in the Joe Gqabi District: Eastern Cape
- Authors: Tetana, Thando
- Date: 2016
- Subjects: Cardiovascular disease Coronary heart disease -- South Africa -- Eastern Cape Coronary heart disease--Risk factors
- Language: English
- Type: Thesis , Masters/Doctoral , M Sc Public Health
- Identifier: http://hdl.handle.net/11260/1440 , vital:35587
- Description: Cardiovascular disease (CVD) such as coronary heart disease (CHD) is a contributing factor to a large percentage of mortalities and morbidities worldwide including in affluent South African setting. In the Eastern Cape of Province, South Africa, there is no extensive data reported on Coronary Heart Disease (CHD) determinants and risk factors. The present study sought to assess the risk factors and determinants of CHD. This case (n=50) control (n=50) study matched for sex and age, was conducted among Xhosa adults from rural and semi urban/ township areas of Joe Gqabi District, Eastern Cape Province of South Africa. Non modifiable, environmental, lifestyle, and psychological factors were investigated using univariate analysis and multivariate logistic regression analysis. Depression, alcohol excessive intake, family history of CHD were the CHD univariate risk factors. The independent risk factors of CHD were uncontrolled systolic hypertension (Odds Ratio (OR)=95; 95% Confidence Interval 16.9-128; In front of a multifactorial disease driven by interactions of socio determinants and traditional risk factors, urgent programmes of education, clinical management and health promotion for adequate diet, physical activity, adherence and compliance to medication and are needed to curb epidemic proportions of CVD risk factors.
- Full Text:
- Date Issued: 2016
- Authors: Tetana, Thando
- Date: 2016
- Subjects: Cardiovascular disease Coronary heart disease -- South Africa -- Eastern Cape Coronary heart disease--Risk factors
- Language: English
- Type: Thesis , Masters/Doctoral , M Sc Public Health
- Identifier: http://hdl.handle.net/11260/1440 , vital:35587
- Description: Cardiovascular disease (CVD) such as coronary heart disease (CHD) is a contributing factor to a large percentage of mortalities and morbidities worldwide including in affluent South African setting. In the Eastern Cape of Province, South Africa, there is no extensive data reported on Coronary Heart Disease (CHD) determinants and risk factors. The present study sought to assess the risk factors and determinants of CHD. This case (n=50) control (n=50) study matched for sex and age, was conducted among Xhosa adults from rural and semi urban/ township areas of Joe Gqabi District, Eastern Cape Province of South Africa. Non modifiable, environmental, lifestyle, and psychological factors were investigated using univariate analysis and multivariate logistic regression analysis. Depression, alcohol excessive intake, family history of CHD were the CHD univariate risk factors. The independent risk factors of CHD were uncontrolled systolic hypertension (Odds Ratio (OR)=95; 95% Confidence Interval 16.9-128; In front of a multifactorial disease driven by interactions of socio determinants and traditional risk factors, urgent programmes of education, clinical management and health promotion for adequate diet, physical activity, adherence and compliance to medication and are needed to curb epidemic proportions of CVD risk factors.
- Full Text:
- Date Issued: 2016
Assessing the value of public investment into biological control research for invasive alien plants : the ARC PPRI Weeds Research Division
- Authors: Scarr, Lowell Martin
- Date: 2016
- Subjects: Alien plants -- Biological control , Invasive plants -- Biological control , Alien plants -- Economic aspects , Invasive plants -- Economic aspects , Weeds -- Biological control
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1126 , http://hdl.handle.net/10962/d1020604
- Description: This study investigates the economic impact of the ARC PPRI Weeds Research Division. The Division researches appropriate methods of biological control for invasive alien plants (IAPs). These plants pose an increasing threat to environmental integrity and ecosystem service provision impacting on economic potential. Since the work of the Division is considered a public good, a predominantly descriptive approach has been adopted for the valuation process. A combination of quantitative cost analysis and a qualitative study of the impacts of research and invasive alien plants is used to deal with the challenges associated with non-market valuation. The study found that investment into the Weeds Division is a valuable activity that supports the long-term growth potential of the South African economy. The role of a well-functioning environment is highlighted as an essential base for the creation of sustained growth opportunities in any society. It was determined that investment into the Division should be increased into the future to support efficient spending of scarce state funds. Biological control research was found to provide strategic future growth potential, creating opportunities for the development of a competitive advantage in the biotechnology and environmental management sectors. The study adds to the increasing move towards a more holistic view of economic valuation, taking factors other than pure finance and econometrics into consideration. This is an important shift in prevailing economic thought, as a realisation is reached that a single, or even triple, bottom line is an outdated and insufficient decision making basis.
- Full Text:
- Date Issued: 2016
- Authors: Scarr, Lowell Martin
- Date: 2016
- Subjects: Alien plants -- Biological control , Invasive plants -- Biological control , Alien plants -- Economic aspects , Invasive plants -- Economic aspects , Weeds -- Biological control
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1126 , http://hdl.handle.net/10962/d1020604
- Description: This study investigates the economic impact of the ARC PPRI Weeds Research Division. The Division researches appropriate methods of biological control for invasive alien plants (IAPs). These plants pose an increasing threat to environmental integrity and ecosystem service provision impacting on economic potential. Since the work of the Division is considered a public good, a predominantly descriptive approach has been adopted for the valuation process. A combination of quantitative cost analysis and a qualitative study of the impacts of research and invasive alien plants is used to deal with the challenges associated with non-market valuation. The study found that investment into the Weeds Division is a valuable activity that supports the long-term growth potential of the South African economy. The role of a well-functioning environment is highlighted as an essential base for the creation of sustained growth opportunities in any society. It was determined that investment into the Division should be increased into the future to support efficient spending of scarce state funds. Biological control research was found to provide strategic future growth potential, creating opportunities for the development of a competitive advantage in the biotechnology and environmental management sectors. The study adds to the increasing move towards a more holistic view of economic valuation, taking factors other than pure finance and econometrics into consideration. This is an important shift in prevailing economic thought, as a realisation is reached that a single, or even triple, bottom line is an outdated and insufficient decision making basis.
- Full Text:
- Date Issued: 2016
Assessing the vulnerability of resource-poor households to disasters associated with climate variability using remote sensing and GIS techniques in the Nkonkobe Local Municipality, Eastern Cape Province, South Africa
- Authors: Chari, Martin Munashe
- Date: 2016
- Subjects: Climatic changes -- Forecasting Natural resources -- Remote sensing Droughts -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2425 , vital:27837
- Description: The main objective of the study was to assess the extent to which resource-poor households in selected villages of Nkonkobe Local Municipality in the Eastern Cape Province of South Africa are vulnerable to drought by using an improvised remote sensing and Geographic Information System (GIS)-based mapping approach. The research methodology was comprised of 1) assessment of vulnerability levels and 2) the calculation of established drought assessment indices comprising the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) from wet-season Landsat images covering a period of 29 years from 1985 to 2014 in order to objectively determine the temporal recurrence of drought in Nkonkobe Local Municipality. Vulnerability of households to drought was determined by using a multi-step GIS-based mapping approach in which 3 components comprising exposure, sensitivity and adaptive capacity were simultaneously analysed and averaged to determine the magnitude of vulnerability. Thereafter, the Analytical Hierarchy Process (AHP) was used to establish weighted contributions of these components to vulnerability. The weights applied to the AHP were obtained from the 2012 - 2017 Nkonkobe Integrated Development Plan (IDP) and perceptions that were solicited from key informants who were judged to be knowledgeable about the subject. A Kruskal-Wallis H test on demographic data for water access revealed that the demographic results are independent of choice of data acquired from different data providers (χ2(2) = 1.26, p = 0.533, with a mean ranked population scores of 7.4 for ECSECC, 6.8 for Quantec and 9.8 for StatsSA). Simple linear regression analysis revealed strong positive correlations between NDWI and NDVI ((r = 0.99609375, R2 = 1, for 1985), 1995 (r = 0.99609375, R2 = 1 for 1995), (r = 0.99609375, R2 = 1 for 2005) and (r = 0.99609375, R2 = 1 for 2014). The regression analysis proved that vegetation condition depends on surface water arising from rainfall. The results indicate that the whole of Nkonkobe Local Municipality is susceptible to drought with villages in south eastern part being most vulnerable to droughts due to high sensitivity and low adaptive capacity.
- Full Text:
- Date Issued: 2016
- Authors: Chari, Martin Munashe
- Date: 2016
- Subjects: Climatic changes -- Forecasting Natural resources -- Remote sensing Droughts -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2425 , vital:27837
- Description: The main objective of the study was to assess the extent to which resource-poor households in selected villages of Nkonkobe Local Municipality in the Eastern Cape Province of South Africa are vulnerable to drought by using an improvised remote sensing and Geographic Information System (GIS)-based mapping approach. The research methodology was comprised of 1) assessment of vulnerability levels and 2) the calculation of established drought assessment indices comprising the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) from wet-season Landsat images covering a period of 29 years from 1985 to 2014 in order to objectively determine the temporal recurrence of drought in Nkonkobe Local Municipality. Vulnerability of households to drought was determined by using a multi-step GIS-based mapping approach in which 3 components comprising exposure, sensitivity and adaptive capacity were simultaneously analysed and averaged to determine the magnitude of vulnerability. Thereafter, the Analytical Hierarchy Process (AHP) was used to establish weighted contributions of these components to vulnerability. The weights applied to the AHP were obtained from the 2012 - 2017 Nkonkobe Integrated Development Plan (IDP) and perceptions that were solicited from key informants who were judged to be knowledgeable about the subject. A Kruskal-Wallis H test on demographic data for water access revealed that the demographic results are independent of choice of data acquired from different data providers (χ2(2) = 1.26, p = 0.533, with a mean ranked population scores of 7.4 for ECSECC, 6.8 for Quantec and 9.8 for StatsSA). Simple linear regression analysis revealed strong positive correlations between NDWI and NDVI ((r = 0.99609375, R2 = 1, for 1985), 1995 (r = 0.99609375, R2 = 1 for 1995), (r = 0.99609375, R2 = 1 for 2005) and (r = 0.99609375, R2 = 1 for 2014). The regression analysis proved that vegetation condition depends on surface water arising from rainfall. The results indicate that the whole of Nkonkobe Local Municipality is susceptible to drought with villages in south eastern part being most vulnerable to droughts due to high sensitivity and low adaptive capacity.
- Full Text:
- Date Issued: 2016
Assessment of fluctuating asymmetry as an indicator of water quality stress in South Africa
- Authors: Holland, Alexandra Jennifer
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/430 , vital:19958
- Description: South Africa’s freshwater resources are facing numerous water quality challenges and need to be protected from degradation and pollution by appropriate management strategies as they are a limited and shared resource. The South African Scoring System (SASS5), which assesses macroinvertebrate communities at family level, is used in routine monitoring of riverine ecosystems in South Africa. Assessing the condition of these ecosystems is limited as SASS5 does not allow for changes at lower levels of biological organisation to be detected. Fluctuating asymmetry (FA) - small random deviations from perfect symmetry - is considered a direct measure of developmental instability. This phenotypical response results from numerous internal and external factors and has a low level of heritability. FA is based on sound scientific principles, easy to measure, biologically robust and cost-effective. It reflects synergistic interactions between stressors and provides an integrated measure of several anthropogenic stresses, which strengthens the assertion that FA is an environmental indicator of water quality stress, and can potentially be used to detect stress in populations before irreversible effects manifest. FA responses were investigated by (1) exposing freshwater shrimp to increasing concentrations of cadmium chloride in a long-term experiment and (2) comparing FA responses to water quality changes and macroinvertebrate community responses in two case studies (Kwazulu-Natal and Limpopo Province) in South Africa. Although no consistent concentration-response curve could be established, this study suggests that FA responses can be used as a sublethal endpoint in exposure experiments. Determining water quality parameters causing FA responses was not possible in field collected freshwater shrimp in either case study. Although FA did not specifically respond to any of the measured water quality parameters identified in the case studies, it has potential as a general indicator of water quality stress in freshwater shrimp. This study shows that FA responses are potentially more sensitive than macroinvertebrate community responses to pollution since it is not affected by habitat. Since FA has the potential to be a general indicator of population quality, particularly where there are natural habitat differences, it can be useful at the level of biomonitoring required for routine basic river status assessments in South Africa. However, in order for FA to become a robust tool that can be used routinely in conjunction with SASS5 more research is required.
- Full Text:
- Date Issued: 2016
- Authors: Holland, Alexandra Jennifer
- Date: 2016
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/430 , vital:19958
- Description: South Africa’s freshwater resources are facing numerous water quality challenges and need to be protected from degradation and pollution by appropriate management strategies as they are a limited and shared resource. The South African Scoring System (SASS5), which assesses macroinvertebrate communities at family level, is used in routine monitoring of riverine ecosystems in South Africa. Assessing the condition of these ecosystems is limited as SASS5 does not allow for changes at lower levels of biological organisation to be detected. Fluctuating asymmetry (FA) - small random deviations from perfect symmetry - is considered a direct measure of developmental instability. This phenotypical response results from numerous internal and external factors and has a low level of heritability. FA is based on sound scientific principles, easy to measure, biologically robust and cost-effective. It reflects synergistic interactions between stressors and provides an integrated measure of several anthropogenic stresses, which strengthens the assertion that FA is an environmental indicator of water quality stress, and can potentially be used to detect stress in populations before irreversible effects manifest. FA responses were investigated by (1) exposing freshwater shrimp to increasing concentrations of cadmium chloride in a long-term experiment and (2) comparing FA responses to water quality changes and macroinvertebrate community responses in two case studies (Kwazulu-Natal and Limpopo Province) in South Africa. Although no consistent concentration-response curve could be established, this study suggests that FA responses can be used as a sublethal endpoint in exposure experiments. Determining water quality parameters causing FA responses was not possible in field collected freshwater shrimp in either case study. Although FA did not specifically respond to any of the measured water quality parameters identified in the case studies, it has potential as a general indicator of water quality stress in freshwater shrimp. This study shows that FA responses are potentially more sensitive than macroinvertebrate community responses to pollution since it is not affected by habitat. Since FA has the potential to be a general indicator of population quality, particularly where there are natural habitat differences, it can be useful at the level of biomonitoring required for routine basic river status assessments in South Africa. However, in order for FA to become a robust tool that can be used routinely in conjunction with SASS5 more research is required.
- Full Text:
- Date Issued: 2016
Assessment of government spending austerity measures in on-site school support for curriculum delivery: a case of Idutywa Education District
- Authors: Lombo, Nomachule
- Date: 2016
- Subjects: Government spending policy -- South Africa -- Eastern Cape Financial crises -- South Africa -- Eastern Cape Debts, Public -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2038 , vital:27600
- Description: The view of on-site school support for curriculum delivery is shared by most countries and its effects have been felt by schools. There is fear that the Austerity Measures will negate the outcomes of the action taken by the teams that visit the schools. The reviewed literature is more biased towards the Austerity Measures in the whole government sector rather than in a department or an institution like the Education District in Idutywa. Even though the effects of Austerity Measures have been researched all over the world based on a specific country, there is deficiency of such literature done in the institution like the department of Education Districts. The researcher intends contributing to the filling of this gap by this study. The researcher therefore carried out a focused study of the effect of Department’s Austerity Measures on on-site school curriculum support in Idutywa Education District. It is also imperative to know how the teachers are affected by these departmental Austerity Measures, hence the interviews were carried out with the school personnel in addition to the District Professional staff. The District is characterised by poor performance in both Annual National Assessment (ANA) and the final National Senior Certificate results. The findings revealed that the implementation of AM have contributed to, amongst other things, the following issues: The inadequate on-site school support for curriculum delivery; The shortage of resources that includes teachers and vehicles; and ultimately the learner underperformance The researcher expect that the recommendation made will be embraced and be factored through, during the planning process of the Eastern Cape Department of Basic Education in order to improve learner performance.
- Full Text:
- Date Issued: 2016
- Authors: Lombo, Nomachule
- Date: 2016
- Subjects: Government spending policy -- South Africa -- Eastern Cape Financial crises -- South Africa -- Eastern Cape Debts, Public -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2038 , vital:27600
- Description: The view of on-site school support for curriculum delivery is shared by most countries and its effects have been felt by schools. There is fear that the Austerity Measures will negate the outcomes of the action taken by the teams that visit the schools. The reviewed literature is more biased towards the Austerity Measures in the whole government sector rather than in a department or an institution like the Education District in Idutywa. Even though the effects of Austerity Measures have been researched all over the world based on a specific country, there is deficiency of such literature done in the institution like the department of Education Districts. The researcher intends contributing to the filling of this gap by this study. The researcher therefore carried out a focused study of the effect of Department’s Austerity Measures on on-site school curriculum support in Idutywa Education District. It is also imperative to know how the teachers are affected by these departmental Austerity Measures, hence the interviews were carried out with the school personnel in addition to the District Professional staff. The District is characterised by poor performance in both Annual National Assessment (ANA) and the final National Senior Certificate results. The findings revealed that the implementation of AM have contributed to, amongst other things, the following issues: The inadequate on-site school support for curriculum delivery; The shortage of resources that includes teachers and vehicles; and ultimately the learner underperformance The researcher expect that the recommendation made will be embraced and be factored through, during the planning process of the Eastern Cape Department of Basic Education in order to improve learner performance.
- Full Text:
- Date Issued: 2016