Studies on the antimicrobial, antioxidant and antiproliferative potential of the ethyl acetate extract and compounds of Peltophorum africanum
- Authors: Okeleye, Benjamin Ifeoluwa
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11282 , http://hdl.handle.net/10353/d1016165
- Description: Cells are constantly exposed to a variety of oxidizing agents, some of which are necessary for life. Oxidants produced in excess can cause an imbalance, leading to oxidative stress, especially in chronic bacterial, viral, and parasitic infections. This can result to damage of biomolecules such as lipids, proteins, and DNA, hence, an increased risk for cancer. Plants have a long history of use in the treatment of cancer. Plant secondary metabolites have proved to be an excellent reservoir of new medical compounds. Fruits, vegetables, and whole grains contain a wide variety of antioxidant phytochemicals, such as phenolics and carotenoids, and may help protect cellular systems from oxidative damage and also may lower the risk of chronic diseases. Peltophorum africanum, a member of the family Fabaceae (Sond) is also known as the African weeping wattle and is used in traditional medicine in South Africa. This study investigated the antimicrobial, antioxidant and antiproliferative potential of the ethyl acetate extract and compounds of Peltophorum africanum in order to validate its pharmacological use. The study assessed the in vitro antimicrobial activity of ethyl acetate extract (EAE) of Peltophorum africanum stem bark and its fractions by the agar well and macrodilution methods. The toxicity on a normal human liver cell (Chang liver cell) and antiproliferation of human breast (MCF-7), colon (HT-29) and cervical (HeLa) cancer cell lines were determined using the CellTiter-Blue cell viability assay and the mechanism of action delineated using the Nucleic Acid and Protein Purification Nucleospin® Tissue Kit, Scanning Electron Microscopy (SEM), Propidium iodide (PI) and Acridine orange (AO) double-staining techniques, the Cleaved Caspase 3 (Asp 175) Alexa Fluor® 488 Antibody and the Coulter® DNA PrepTM Reagents Kit. Purification and identification of the compounds from EAE and fractions as well as the morphological alteration of bacteria, yeast and cancer cells were determined using thin layer chromatography, infrared spectra fingerprint and GC-MS analysis, micro-dilution and scanning electron microscopy with energy-dispersive X-ray analysis. In vitro antioxidant activity of EAE was determined by means of radical scavenging and ferric reducing power analysis using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2`-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) kit, hydrogen peroxide (H2O2), iron (iii) chloride (Fe3+) and nitric oxide (NO). To assess the likely effects of secondary metabolites on the activities observed; total proanthocyanidins, phenolics, flavonols, and flavonoids were determined using standard phytochemical methods. Data were analyzed by one way analysis of variance (ANOVA; SPSS Version 17.0, 2011), regression analysis (MINITAB, version 12 for windows), probit analysis test (software NCSS, 2007) and GraphPad Prism4 software package. The p-values < 0.05 were considered significant. Marked activity of the extract was observed against Plesiomonas shigelloides ATCC 51903, with MIC and MLC values of 0.15625 and 0.3125mg/mL, respectively. The extract was both bactericidal (MICindex ≤ 2) and bacteriostatic/fungistatic (MICindex > 2) in activity. Lethal dose at 50 (LD50) showed 82.64 ± 1.40 degree of toxicity at 24 hrs, and 95 percentile of cell death dose activity ranged from log 3.12 ± 0.01 to 4.59 ± 0.03. The activity of the eight fractions tested ranged from 1.0 ± 0.5 to 3.7 ± 1.6 mg/mL (IC50) and from 2.1 ± 0.8 to 6.25 ± 0 mg/mL (IC90) (Chapter 3). Due to the effect of compounds present in the crude extract and fractions, the P. aeruginosa treated with EAE had a reduction of sodium from 5.55 % (untreated) - 1.50 %. For C. albicans, pottasium was reduced from 4.16 % (untreated) - 0.76 % (T1). Remarkable morphological alterations were observed including deformation of the germ tubes and perforation of the cell wall (Chapter 4). Extract scavenging activity of 88.73± 6.69 % (25 μg mL-1), 53.93±1.09 % (25 μg mL-1) were recorded for H2O2 and NO respectively with proanthocyanidins (92.18±4.68 mg/g) occurring more (p < 0.05) in the extract compared to all other phenolics compounds (Chapter 5). Significant reduction in cell viability of the cells was noted as the MCF-7 cells were reduced from 100 - 54.33±1.84 % after 72 hrs of treatment with 5 μg/mL of EAE (P. value < 0.05). TEt10 was cytotoxic against human normal cells (chang liver cell) at EC50 of 37 μg/mL and 74 μg/mL after 24 and 48 h of treatment respectively. Marked antiproliferative activity of 13.2 μg/mL (EC50) was observed when HeLa cells were treated for 48 h. Internucleosomal DNA of MCF-7, HT-29 and HeLa cells randomly fragmented into an uninterrupted spectrum of sizes, complemented by the intercalation of nucleic acid-specific fluorochromes by PI and AO spotting two phases of apoptosis; early (EA) and late (LA) apoptosis. Distinctive ultramorphological changes observed include; cell shrinkage, membrane blebbing, and typical cell induced death. The study also recorded 705.102 ± 28.56 % TEt10 caspase-3 activity compared to curcumin 592.857 ± 165.76 % (positive control) and untreated (negative control; 100 ± 15.81 %) cells. Percentage HeLa cell with Sub-G1 DNA phase increased from 0.13 ± 0.06 % (negative control) to 13.8 ± 3.04 % compared to curcumin (8.17 ± 2.20 %) after treatment with TEt10. The compounds identified in the fractions including Colchicine, N-(trifluoroacetyl)methyl-N-deacetyl-, Lupeol and .gamma.-Sitosterol may be responsible for the induction of apoptosis observed and could be further studied in vivo as a potential template for new anticancer treatment (Chapter 6 & 7).
- Full Text:
- Date Issued: 2014
- Authors: Okeleye, Benjamin Ifeoluwa
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11282 , http://hdl.handle.net/10353/d1016165
- Description: Cells are constantly exposed to a variety of oxidizing agents, some of which are necessary for life. Oxidants produced in excess can cause an imbalance, leading to oxidative stress, especially in chronic bacterial, viral, and parasitic infections. This can result to damage of biomolecules such as lipids, proteins, and DNA, hence, an increased risk for cancer. Plants have a long history of use in the treatment of cancer. Plant secondary metabolites have proved to be an excellent reservoir of new medical compounds. Fruits, vegetables, and whole grains contain a wide variety of antioxidant phytochemicals, such as phenolics and carotenoids, and may help protect cellular systems from oxidative damage and also may lower the risk of chronic diseases. Peltophorum africanum, a member of the family Fabaceae (Sond) is also known as the African weeping wattle and is used in traditional medicine in South Africa. This study investigated the antimicrobial, antioxidant and antiproliferative potential of the ethyl acetate extract and compounds of Peltophorum africanum in order to validate its pharmacological use. The study assessed the in vitro antimicrobial activity of ethyl acetate extract (EAE) of Peltophorum africanum stem bark and its fractions by the agar well and macrodilution methods. The toxicity on a normal human liver cell (Chang liver cell) and antiproliferation of human breast (MCF-7), colon (HT-29) and cervical (HeLa) cancer cell lines were determined using the CellTiter-Blue cell viability assay and the mechanism of action delineated using the Nucleic Acid and Protein Purification Nucleospin® Tissue Kit, Scanning Electron Microscopy (SEM), Propidium iodide (PI) and Acridine orange (AO) double-staining techniques, the Cleaved Caspase 3 (Asp 175) Alexa Fluor® 488 Antibody and the Coulter® DNA PrepTM Reagents Kit. Purification and identification of the compounds from EAE and fractions as well as the morphological alteration of bacteria, yeast and cancer cells were determined using thin layer chromatography, infrared spectra fingerprint and GC-MS analysis, micro-dilution and scanning electron microscopy with energy-dispersive X-ray analysis. In vitro antioxidant activity of EAE was determined by means of radical scavenging and ferric reducing power analysis using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2, 2`-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) kit, hydrogen peroxide (H2O2), iron (iii) chloride (Fe3+) and nitric oxide (NO). To assess the likely effects of secondary metabolites on the activities observed; total proanthocyanidins, phenolics, flavonols, and flavonoids were determined using standard phytochemical methods. Data were analyzed by one way analysis of variance (ANOVA; SPSS Version 17.0, 2011), regression analysis (MINITAB, version 12 for windows), probit analysis test (software NCSS, 2007) and GraphPad Prism4 software package. The p-values < 0.05 were considered significant. Marked activity of the extract was observed against Plesiomonas shigelloides ATCC 51903, with MIC and MLC values of 0.15625 and 0.3125mg/mL, respectively. The extract was both bactericidal (MICindex ≤ 2) and bacteriostatic/fungistatic (MICindex > 2) in activity. Lethal dose at 50 (LD50) showed 82.64 ± 1.40 degree of toxicity at 24 hrs, and 95 percentile of cell death dose activity ranged from log 3.12 ± 0.01 to 4.59 ± 0.03. The activity of the eight fractions tested ranged from 1.0 ± 0.5 to 3.7 ± 1.6 mg/mL (IC50) and from 2.1 ± 0.8 to 6.25 ± 0 mg/mL (IC90) (Chapter 3). Due to the effect of compounds present in the crude extract and fractions, the P. aeruginosa treated with EAE had a reduction of sodium from 5.55 % (untreated) - 1.50 %. For C. albicans, pottasium was reduced from 4.16 % (untreated) - 0.76 % (T1). Remarkable morphological alterations were observed including deformation of the germ tubes and perforation of the cell wall (Chapter 4). Extract scavenging activity of 88.73± 6.69 % (25 μg mL-1), 53.93±1.09 % (25 μg mL-1) were recorded for H2O2 and NO respectively with proanthocyanidins (92.18±4.68 mg/g) occurring more (p < 0.05) in the extract compared to all other phenolics compounds (Chapter 5). Significant reduction in cell viability of the cells was noted as the MCF-7 cells were reduced from 100 - 54.33±1.84 % after 72 hrs of treatment with 5 μg/mL of EAE (P. value < 0.05). TEt10 was cytotoxic against human normal cells (chang liver cell) at EC50 of 37 μg/mL and 74 μg/mL after 24 and 48 h of treatment respectively. Marked antiproliferative activity of 13.2 μg/mL (EC50) was observed when HeLa cells were treated for 48 h. Internucleosomal DNA of MCF-7, HT-29 and HeLa cells randomly fragmented into an uninterrupted spectrum of sizes, complemented by the intercalation of nucleic acid-specific fluorochromes by PI and AO spotting two phases of apoptosis; early (EA) and late (LA) apoptosis. Distinctive ultramorphological changes observed include; cell shrinkage, membrane blebbing, and typical cell induced death. The study also recorded 705.102 ± 28.56 % TEt10 caspase-3 activity compared to curcumin 592.857 ± 165.76 % (positive control) and untreated (negative control; 100 ± 15.81 %) cells. Percentage HeLa cell with Sub-G1 DNA phase increased from 0.13 ± 0.06 % (negative control) to 13.8 ± 3.04 % compared to curcumin (8.17 ± 2.20 %) after treatment with TEt10. The compounds identified in the fractions including Colchicine, N-(trifluoroacetyl)methyl-N-deacetyl-, Lupeol and .gamma.-Sitosterol may be responsible for the induction of apoptosis observed and could be further studied in vivo as a potential template for new anticancer treatment (Chapter 6 & 7).
- Full Text:
- Date Issued: 2014
Synoptic circulation patterns and its relationship with ground thermal characteristics along an altitudinal transect on sub-Antarctic Marion Island
- Authors: Bierman, Stefni
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11516 , http://hdl.handle.net/10353/d1015532
- Description: The climate of Marion Island is driven by synoptic weather patterns which have also been suggested to influence the soil thermal characteristics. The primary aim of this work was to examine the effect of synoptic weather systems on soil temperature dynamics on an altitudinal gradient on the eastern side of Marion Island. The study specifically addresses the implications of climate change on future soil thermal dynamics in a maritime sub-Antarctic environment. Ground temperature were obtained from three ground temperature monitoring stations on the eastern side of Marion Island, which were established along an altitudinal gradient at Long Ridge North (200m a.s.l.), Katedraalkrans (750m a.s.l) and at Delta Extension (1000m a.s.l.). To assess the synoptic weather circulation patterns, a synoptic climate classification methodology that is based on the single station principal component (PCA) and cluster analysis were used. Results show that certain clusters were more dominant than others and over the measured time span certain synoptic weather patterns, mainly cyclonic air circulation types, have decreased while anticyclonic circulation have increased. Soil frost occurs at all three stations on Marion Island, not only under cyclonic circulations (as previously suggested) but significantly under anticyclonic air mass circulation as well. Soil frost is dependent on the duration of post-cyclonic Antarctic air mass circulation. Synoptic weather patterns are also affecting ground surface lapse rates. Changes from positive to negative lapse rates were observed and this predominantly occurred under the atmospheric circulation pattern associated with clusters that are predominantly anticyclonic. Long term climatic change as predicted by the PCA show a reduction in low pressure systems or more anticyclonic conditions affecting the island. These change will significantly affect the soil thermal dynamics at an altitudinal scale on sub-Antarctic Marion Island.
- Full Text:
- Date Issued: 2014
- Authors: Bierman, Stefni
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Geography)
- Identifier: vital:11516 , http://hdl.handle.net/10353/d1015532
- Description: The climate of Marion Island is driven by synoptic weather patterns which have also been suggested to influence the soil thermal characteristics. The primary aim of this work was to examine the effect of synoptic weather systems on soil temperature dynamics on an altitudinal gradient on the eastern side of Marion Island. The study specifically addresses the implications of climate change on future soil thermal dynamics in a maritime sub-Antarctic environment. Ground temperature were obtained from three ground temperature monitoring stations on the eastern side of Marion Island, which were established along an altitudinal gradient at Long Ridge North (200m a.s.l.), Katedraalkrans (750m a.s.l) and at Delta Extension (1000m a.s.l.). To assess the synoptic weather circulation patterns, a synoptic climate classification methodology that is based on the single station principal component (PCA) and cluster analysis were used. Results show that certain clusters were more dominant than others and over the measured time span certain synoptic weather patterns, mainly cyclonic air circulation types, have decreased while anticyclonic circulation have increased. Soil frost occurs at all three stations on Marion Island, not only under cyclonic circulations (as previously suggested) but significantly under anticyclonic air mass circulation as well. Soil frost is dependent on the duration of post-cyclonic Antarctic air mass circulation. Synoptic weather patterns are also affecting ground surface lapse rates. Changes from positive to negative lapse rates were observed and this predominantly occurred under the atmospheric circulation pattern associated with clusters that are predominantly anticyclonic. Long term climatic change as predicted by the PCA show a reduction in low pressure systems or more anticyclonic conditions affecting the island. These change will significantly affect the soil thermal dynamics at an altitudinal scale on sub-Antarctic Marion Island.
- Full Text:
- Date Issued: 2014
Synthesis, characterization, and biological studies of pyrazolone Schiff bases and their transition metal complexes
- Authors: Idemudia, Omoruyi Gold
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11340 , http://hdl.handle.net/10353/d1016068
- Description: Some new acylpyrazolone Schiff bases have been synthesized from the condensation reaction of two acylpyrazolone diketone precursors with phenylhydrazine, 2,4-dinitrophenylhydrazine and sulfanilamide. They have been fully characterized by elemental analysis and spectroscopic techniques (IR,1H and 13C NMR, and mass-spectra). The single crystal structure of the benzoyl derivative acylpyrazolone Schiff bases have been obtained and analyzed by X-ray crystallography technique. Solid state X-ray diffraction revealed a keto tautomer Schiff base in solid state. Mn(II), Co(II), Ni(II) and Cu(II) complexes with the Schiff bases have been synthesized and characterized by elemental analysis, IR and UV-VIS spectroscopy, magnetic susceptibility measurements, and thermal studies (TGA and DTG). An octahedral geometry around the transition metal ion, consisting of two bidentate Schiff base ligands bonding through the azometine nitrogen and ketonic oxygen have been proposed based on careful interpretation of available analytical and spectroscopic characterization results. Two water molecules as ligands complete the octahedral geometry in all cases. Using the invitro disc diffusion method for screening synthesized compounds against selected gram positive and gram negative bacterial at 40 mg/mL, and the DPPH free radical scavenging methods at 0.50, 0.25 and 0.13 mg/mL, the synthesized Schiff base and metal complexes showed varying biological activities. 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one sul29 fanilamide showed more activity generally, exhibiting a broad spectrum activity against all selected bacterial in some cases. Mn(II), Co(II) and Ni(II) complexes of sulfanilamide Schiff base with the acetylpyrazolone derivative 4-acetyl-3-methyl-1-phenyl-2-pyrazolin-5-one sulfanilamide, exhibited a stronger and very good DPPH radical scavenging activity as good as ascorbic acid on comparing, but not with Cu(II). As such they could be important antitumour candidates.
- Full Text:
- Date Issued: 2014
- Authors: Idemudia, Omoruyi Gold
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11340 , http://hdl.handle.net/10353/d1016068
- Description: Some new acylpyrazolone Schiff bases have been synthesized from the condensation reaction of two acylpyrazolone diketone precursors with phenylhydrazine, 2,4-dinitrophenylhydrazine and sulfanilamide. They have been fully characterized by elemental analysis and spectroscopic techniques (IR,1H and 13C NMR, and mass-spectra). The single crystal structure of the benzoyl derivative acylpyrazolone Schiff bases have been obtained and analyzed by X-ray crystallography technique. Solid state X-ray diffraction revealed a keto tautomer Schiff base in solid state. Mn(II), Co(II), Ni(II) and Cu(II) complexes with the Schiff bases have been synthesized and characterized by elemental analysis, IR and UV-VIS spectroscopy, magnetic susceptibility measurements, and thermal studies (TGA and DTG). An octahedral geometry around the transition metal ion, consisting of two bidentate Schiff base ligands bonding through the azometine nitrogen and ketonic oxygen have been proposed based on careful interpretation of available analytical and spectroscopic characterization results. Two water molecules as ligands complete the octahedral geometry in all cases. Using the invitro disc diffusion method for screening synthesized compounds against selected gram positive and gram negative bacterial at 40 mg/mL, and the DPPH free radical scavenging methods at 0.50, 0.25 and 0.13 mg/mL, the synthesized Schiff base and metal complexes showed varying biological activities. 4-benzoyl-3-methyl-1-phenyl-2-pyrazolin-5-one sul29 fanilamide showed more activity generally, exhibiting a broad spectrum activity against all selected bacterial in some cases. Mn(II), Co(II) and Ni(II) complexes of sulfanilamide Schiff base with the acetylpyrazolone derivative 4-acetyl-3-methyl-1-phenyl-2-pyrazolin-5-one sulfanilamide, exhibited a stronger and very good DPPH radical scavenging activity as good as ascorbic acid on comparing, but not with Cu(II). As such they could be important antitumour candidates.
- Full Text:
- Date Issued: 2014
Targeting and characterizing potentially high yield aquifers in the neotectonic zones in the Eastern Cape Province in South Africa
- Authors: Madi, Kakaba
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: vital:11530 , http://hdl.handle.net/10353/d1021270
- Description: The Eastern Cape Province has, besides the three known neotectonic belts (southern, eastern and northern) a fourth zone, which is inactive. This inactive zone is located almost in its central part north of the southern neotectonic zone, and south of the northern neotectonic belt. The three above mentioned neotectonic belts (southern, eastern and northern) were chosen for this study, each one with its own characteristics. This study aims at characterizing and targeting potentially high yield aquifers in the neotectonic zones in the Eastern Cape Province. The methods used in this study include: 1) A comprehensive literature review on neotectonics in South Africa in general and in the Eastern Cape Province in particular; 2) Extraction of lineaments through remote sensing and examination of digital elevation models; 3) Examination of seismic data for the subsurface visualization onshore and offshore; 4) Study on the genesis of the Grahamstown kaolin deposits through the structural component; and 5) Acquisition and interpretation of magnetic, electromagnetic and radiometric data from three of the hot springs in the northern neotectonic belt. The results indicate the following: 1) Old map of seismic epicentres in South Africa need to be reviewed continually. The Eastern Cape was regarded as quiescent in terms of seismicity. However, the investigation from recent seismic epicenters downloadable from the IRIS website has shown that recent seismic events occurred in the Eastern Cape Province especially in the northern and southern neotectonic belts. The central part located north of the southern neotectonic belt and south of the northern neotectonic belt is inactive. This inactive zone can be considered for the storage of nuclear wastes. 2) The eastern neotectonic belt has, like the northern neotectonic belt, a higher density of lineaments oriented northwest-southeast, which makes it the second important neotectonic belt. These lineaments correlate with the normalized difference vegetation index indicative of a good circulation of groundwater. In the south, the Eastern Cape great lineament oriented east-west is now considered a neotectonic domain because many seismic epicentres occur therein. Its geomorphologic shape in graben type form is a favourable structure for groundwater catchment. The surface topography is not uniform and high elevations in the east are related to the uplift that took place in the Quaternary. Most vector gradients are oriented east-west, a fact to be reckon with in the study of surface water flow and aquifers characterization. 3) Offshore along the east coast, the subsurface is affected by neotectonic faults, which are probably splays of the Agulhas Falkland Fractured Zone (AFFZ). The folds that occur are related to the regional compressional stress known as the Wegener Stress Anomaly (WSM). On land, straight lines from seismic profiles indicate that weathering occurs in consolidated materials probably along faults or fractures, unconsolidated sediments always have wavy profiles. On the other hand, field observations in King Williams Town have clearly shown that a tectonic uplift took place on a dolerite sill overlain by mudstones and sandstones. The uplift is possibly related to the Amatole-Swaziland event that occurred in the last five millions years. The escarpment along this dolerite sill overlain by sedimentary rocks is a meso-scale fault with a dip-slip component. Healthy vegetation and a river flowing parallel to the cliff indicate groundwater flow in the zone of weakness. 4) In the southern neotectonic belt there is a clear northwest-southeast horizontal compression and a southwest-northeast vertical to sub-vertical extension. Enrichment of granitic breccias and feldspar in the Grahamstown Dwyka tillite is the source for the formation of kaolin deposits. The weathering starts in the granitic breccias through their extensional fractures and then extends in the matrix, which has micro-fractures that are only visible with the transmitted microscope. Combined extensional strike-slip and dip-slip faulting is responsible for the earthquakes in the region of Grahamstown where the kaolin is formed. There is also an unreported thermal (quartz veins) and neotectonic event identified in this region. 5) The hot springs in the northern neotectonic belt are connected by a regional neotectonic fault. The use of magnetic and electromagnetic methods helped to decipher the occurrence of faults, fractures, dolerite dykes, and variable degree of weathering. Uranium/potassium ratios derived from radiometric surveys show that areas around some hot springs are characterized by enrichment in uranium. High concentrations of thorium are related to its low capacity of being easily dissolved in water. It can be concluded that seismicity, hot springs and accordingly deep groundwater circulation, high density of lineaments, quaternary tectonic uplift, are the predominate characteristics of the three neotectonic zones. Furthermore, on the environmental point of view, thorium concentration is higher than that of either uranium or potassium. Although it is nonetheless below the world average threshold of 7.4 ppm according to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), it may be a source of radiation hazard to humans and animals if they are subjected to prolonged exposure. All the neotectonic zones in the Eastern Cape Province present potentials to host good and important aquifers. It is suggested that the Eastern Cape great lineament in the southern neotectonic belt and the Kokstad-Koffiefontein seismic belt in the northern neotectonic belt, be monitored for future research regarding, neotectonics, seismic risk assessment and hydrogeology.
- Full Text:
- Date Issued: 2014
- Authors: Madi, Kakaba
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: vital:11530 , http://hdl.handle.net/10353/d1021270
- Description: The Eastern Cape Province has, besides the three known neotectonic belts (southern, eastern and northern) a fourth zone, which is inactive. This inactive zone is located almost in its central part north of the southern neotectonic zone, and south of the northern neotectonic belt. The three above mentioned neotectonic belts (southern, eastern and northern) were chosen for this study, each one with its own characteristics. This study aims at characterizing and targeting potentially high yield aquifers in the neotectonic zones in the Eastern Cape Province. The methods used in this study include: 1) A comprehensive literature review on neotectonics in South Africa in general and in the Eastern Cape Province in particular; 2) Extraction of lineaments through remote sensing and examination of digital elevation models; 3) Examination of seismic data for the subsurface visualization onshore and offshore; 4) Study on the genesis of the Grahamstown kaolin deposits through the structural component; and 5) Acquisition and interpretation of magnetic, electromagnetic and radiometric data from three of the hot springs in the northern neotectonic belt. The results indicate the following: 1) Old map of seismic epicentres in South Africa need to be reviewed continually. The Eastern Cape was regarded as quiescent in terms of seismicity. However, the investigation from recent seismic epicenters downloadable from the IRIS website has shown that recent seismic events occurred in the Eastern Cape Province especially in the northern and southern neotectonic belts. The central part located north of the southern neotectonic belt and south of the northern neotectonic belt is inactive. This inactive zone can be considered for the storage of nuclear wastes. 2) The eastern neotectonic belt has, like the northern neotectonic belt, a higher density of lineaments oriented northwest-southeast, which makes it the second important neotectonic belt. These lineaments correlate with the normalized difference vegetation index indicative of a good circulation of groundwater. In the south, the Eastern Cape great lineament oriented east-west is now considered a neotectonic domain because many seismic epicentres occur therein. Its geomorphologic shape in graben type form is a favourable structure for groundwater catchment. The surface topography is not uniform and high elevations in the east are related to the uplift that took place in the Quaternary. Most vector gradients are oriented east-west, a fact to be reckon with in the study of surface water flow and aquifers characterization. 3) Offshore along the east coast, the subsurface is affected by neotectonic faults, which are probably splays of the Agulhas Falkland Fractured Zone (AFFZ). The folds that occur are related to the regional compressional stress known as the Wegener Stress Anomaly (WSM). On land, straight lines from seismic profiles indicate that weathering occurs in consolidated materials probably along faults or fractures, unconsolidated sediments always have wavy profiles. On the other hand, field observations in King Williams Town have clearly shown that a tectonic uplift took place on a dolerite sill overlain by mudstones and sandstones. The uplift is possibly related to the Amatole-Swaziland event that occurred in the last five millions years. The escarpment along this dolerite sill overlain by sedimentary rocks is a meso-scale fault with a dip-slip component. Healthy vegetation and a river flowing parallel to the cliff indicate groundwater flow in the zone of weakness. 4) In the southern neotectonic belt there is a clear northwest-southeast horizontal compression and a southwest-northeast vertical to sub-vertical extension. Enrichment of granitic breccias and feldspar in the Grahamstown Dwyka tillite is the source for the formation of kaolin deposits. The weathering starts in the granitic breccias through their extensional fractures and then extends in the matrix, which has micro-fractures that are only visible with the transmitted microscope. Combined extensional strike-slip and dip-slip faulting is responsible for the earthquakes in the region of Grahamstown where the kaolin is formed. There is also an unreported thermal (quartz veins) and neotectonic event identified in this region. 5) The hot springs in the northern neotectonic belt are connected by a regional neotectonic fault. The use of magnetic and electromagnetic methods helped to decipher the occurrence of faults, fractures, dolerite dykes, and variable degree of weathering. Uranium/potassium ratios derived from radiometric surveys show that areas around some hot springs are characterized by enrichment in uranium. High concentrations of thorium are related to its low capacity of being easily dissolved in water. It can be concluded that seismicity, hot springs and accordingly deep groundwater circulation, high density of lineaments, quaternary tectonic uplift, are the predominate characteristics of the three neotectonic zones. Furthermore, on the environmental point of view, thorium concentration is higher than that of either uranium or potassium. Although it is nonetheless below the world average threshold of 7.4 ppm according to United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), it may be a source of radiation hazard to humans and animals if they are subjected to prolonged exposure. All the neotectonic zones in the Eastern Cape Province present potentials to host good and important aquifers. It is suggested that the Eastern Cape great lineament in the southern neotectonic belt and the Kokstad-Koffiefontein seismic belt in the northern neotectonic belt, be monitored for future research regarding, neotectonics, seismic risk assessment and hydrogeology.
- Full Text:
- Date Issued: 2014
The analysis of the economic impact of climate change on maize production under different farming systems: the case of smallholder Farmers in Jozini Municipality, KwaZulu Natal Province, South Africa
- Authors: Nxumalo, Bongiwe Goodness
- Date: 2014
- Subjects: Climate change mitigation -- South Africa -- KwaZulu-Natal , Irrigation farming -- South Africa -- KwaZulu-Natal , Dry farming -- South Africa -- KwaZulu-Natal , Food supply -- South Africa -- KwaZulu-Natal , Corn -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11229 , http://hdl.handle.net/10353/d1021277 , Climate change mitigation -- South Africa -- KwaZulu-Natal , Irrigation farming -- South Africa -- KwaZulu-Natal , Dry farming -- South Africa -- KwaZulu-Natal , Food supply -- South Africa -- KwaZulu-Natal , Corn -- South Africa -- KwaZulu-Natal
- Description: Maize is the most grown crop by the farmers in Jozini. Therefore, the main objective of the study was to assess the economic impact of climate change on maize production under different farming systems in Jozini Municipality in KwaZulu Natal (KZN). The study was looking at the smallholder farmers producing maize under dryland and irrigation system. A total of 100 farmers were selected for the study (40 from dry-land and 60 from irrigating farmers). Cluster and random sampling procedures were used to select the sample. Questionnaires were used for the collection of primary data, from the respondents (maize farmers). Data was analysed using descriptive statistics (frequency, percentages), gross margin, regression analysis and the Ricardian model. Data for computing gross margins and net revenue was taken from the on-farm trials. Gross margin was used on regression analysis and the net revenue was used on the Ricardian modelThe results of the regression analysis indicated that land size, farmer’s experience to farming, level of education, use of fertiliser, use of irrigation and the yield obtained were significant and have a positive relationship with farmers gross margin. The results of the Ricardian model indicated that climate change affects both farming systems, but farmers that are producing under dryland are the most affected farmers because they rely more on climate variables especially rainfall for their production. So a change in climate variables affects maize farmers’ productivity and thus affecting farmers’ gross margin and net revenue. The study recommends that the farmers must use irrigation in order to support maize production even in the absence of rainfall. Farmers must also adapt to the short growing season so that they will be able to produce even in the presence of climate change.
- Full Text:
- Date Issued: 2014
- Authors: Nxumalo, Bongiwe Goodness
- Date: 2014
- Subjects: Climate change mitigation -- South Africa -- KwaZulu-Natal , Irrigation farming -- South Africa -- KwaZulu-Natal , Dry farming -- South Africa -- KwaZulu-Natal , Food supply -- South Africa -- KwaZulu-Natal , Corn -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11229 , http://hdl.handle.net/10353/d1021277 , Climate change mitigation -- South Africa -- KwaZulu-Natal , Irrigation farming -- South Africa -- KwaZulu-Natal , Dry farming -- South Africa -- KwaZulu-Natal , Food supply -- South Africa -- KwaZulu-Natal , Corn -- South Africa -- KwaZulu-Natal
- Description: Maize is the most grown crop by the farmers in Jozini. Therefore, the main objective of the study was to assess the economic impact of climate change on maize production under different farming systems in Jozini Municipality in KwaZulu Natal (KZN). The study was looking at the smallholder farmers producing maize under dryland and irrigation system. A total of 100 farmers were selected for the study (40 from dry-land and 60 from irrigating farmers). Cluster and random sampling procedures were used to select the sample. Questionnaires were used for the collection of primary data, from the respondents (maize farmers). Data was analysed using descriptive statistics (frequency, percentages), gross margin, regression analysis and the Ricardian model. Data for computing gross margins and net revenue was taken from the on-farm trials. Gross margin was used on regression analysis and the net revenue was used on the Ricardian modelThe results of the regression analysis indicated that land size, farmer’s experience to farming, level of education, use of fertiliser, use of irrigation and the yield obtained were significant and have a positive relationship with farmers gross margin. The results of the Ricardian model indicated that climate change affects both farming systems, but farmers that are producing under dryland are the most affected farmers because they rely more on climate variables especially rainfall for their production. So a change in climate variables affects maize farmers’ productivity and thus affecting farmers’ gross margin and net revenue. The study recommends that the farmers must use irrigation in order to support maize production even in the absence of rainfall. Farmers must also adapt to the short growing season so that they will be able to produce even in the presence of climate change.
- Full Text:
- Date Issued: 2014
The generalization ability of artificial neural networks in forecasting TCP/IP network traffic trends
- Authors: Moyo, Vusumuzi
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11404 , http://hdl.handle.net/10353/d1021127
- Description: Artificial Neural Networks (ANNs) have been used in many fields for a variety of applications, and proved to be reliable. They have proved to be one of the most powerful tools in the domain of forecasting and analysis of various time series. The forecasting of TCP/IP network traffic is an important issue receiving growing attention from the computer networks. By improving upon this task, efficient network traffic engineering and anomaly detection tools can be created, resulting in economic gains from better resource management. The use of ANNs requires some critical decisions on the part of the user. These decisions, which are mainly concerned with the determinations of the components of the network structure and the parameters defined for the learning algorithm, can significantly affect the ability of the ANN to generalize, i.e. to have the outputs of the ANN approximate target values given inputs that are not in the training set. This has an impact on the quality of forecasts produced by the ANN. Although there are some discussions in the literature regarding the issues that affect network generalization ability, there is no standard method or approach that is universally accepted to determine the optimum values of these parameters for a particular problem. This research examined the impact a selection of key design features has on the generalization ability of ANNs. We examined how the size and composition of the network architecture, the size of the training samples, the choice of learning algorithm, the training schedule and the size of the learning rate both individually and collectively affect the ability of an ANN to learn the training data and to generalize well to novel data. To investigate this matter, we empirically conducted several experiments in forecasting a real world TCP/IP network traffic time series and the network performance validated using an independent test set. MATLAB version 7.4.0.287’s Neural Network toolbox version 5.0.2 (R2007a) was used for our experiments. The results are found to be promising in terms of ease of design and use of ANNs. Our results indicate that in contrast to Occam’s razor principle for a single hidden layer an increase in number of hidden neurons produces a corresponding increase in generalization ability of ANNs, however larger networks do not always improve the generalization ability of ANNs even though an increase in number of hidden neurons results in a concomitant rise in network generalization. Also, contradicting commonly accepted guidelines, networks trained with a larger representation of the data, exhibit better generalization than networks trained on smaller representations, even though the larger networks have a significantly greater capacity. Furthermore, the results obtained indicate that the learning rate, momentum, training schedule and choice of learning algorithm have as much a significant effect on ANN generalization ability. A number of conclusions were drawn from the results and later used to generate a comprehensive set of guidelines that will facilitate the process of design and use of ANNs in TCP/IP network traffic forecasting. The main contribution of this research lies in the identification of optimal strategies for the use of ANNs in forecasting TCP/IP network traffic trends. Although the information obtained from the tests carried out in this research is specific to the problem considered, it provides users of back-propagation networks with a valuable guide on the behaviour of networks under a wide range of operating conditions. It is important to note that the guidelines accrued from this research are of an assistive and not necessarily restrictive nature to potential ANN modellers.
- Full Text:
- Date Issued: 2014
- Authors: Moyo, Vusumuzi
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11404 , http://hdl.handle.net/10353/d1021127
- Description: Artificial Neural Networks (ANNs) have been used in many fields for a variety of applications, and proved to be reliable. They have proved to be one of the most powerful tools in the domain of forecasting and analysis of various time series. The forecasting of TCP/IP network traffic is an important issue receiving growing attention from the computer networks. By improving upon this task, efficient network traffic engineering and anomaly detection tools can be created, resulting in economic gains from better resource management. The use of ANNs requires some critical decisions on the part of the user. These decisions, which are mainly concerned with the determinations of the components of the network structure and the parameters defined for the learning algorithm, can significantly affect the ability of the ANN to generalize, i.e. to have the outputs of the ANN approximate target values given inputs that are not in the training set. This has an impact on the quality of forecasts produced by the ANN. Although there are some discussions in the literature regarding the issues that affect network generalization ability, there is no standard method or approach that is universally accepted to determine the optimum values of these parameters for a particular problem. This research examined the impact a selection of key design features has on the generalization ability of ANNs. We examined how the size and composition of the network architecture, the size of the training samples, the choice of learning algorithm, the training schedule and the size of the learning rate both individually and collectively affect the ability of an ANN to learn the training data and to generalize well to novel data. To investigate this matter, we empirically conducted several experiments in forecasting a real world TCP/IP network traffic time series and the network performance validated using an independent test set. MATLAB version 7.4.0.287’s Neural Network toolbox version 5.0.2 (R2007a) was used for our experiments. The results are found to be promising in terms of ease of design and use of ANNs. Our results indicate that in contrast to Occam’s razor principle for a single hidden layer an increase in number of hidden neurons produces a corresponding increase in generalization ability of ANNs, however larger networks do not always improve the generalization ability of ANNs even though an increase in number of hidden neurons results in a concomitant rise in network generalization. Also, contradicting commonly accepted guidelines, networks trained with a larger representation of the data, exhibit better generalization than networks trained on smaller representations, even though the larger networks have a significantly greater capacity. Furthermore, the results obtained indicate that the learning rate, momentum, training schedule and choice of learning algorithm have as much a significant effect on ANN generalization ability. A number of conclusions were drawn from the results and later used to generate a comprehensive set of guidelines that will facilitate the process of design and use of ANNs in TCP/IP network traffic forecasting. The main contribution of this research lies in the identification of optimal strategies for the use of ANNs in forecasting TCP/IP network traffic trends. Although the information obtained from the tests carried out in this research is specific to the problem considered, it provides users of back-propagation networks with a valuable guide on the behaviour of networks under a wide range of operating conditions. It is important to note that the guidelines accrued from this research are of an assistive and not necessarily restrictive nature to potential ANN modellers.
- Full Text:
- Date Issued: 2014
The impact of land and agrarian reforms on poverty alleviation: lessons from the Jay Dee Rovon workers trust and Mon Desire in Joubertina, Eastern Cape-South Africa
- Authors: Mqikela, Ntombozuko
- Date: 2014
- Subjects: Land reform -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11207 , http://hdl.handle.net/10353/d1016070 , Land reform -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Description: The broad objective of the study is to investigate the impact of Land and Agrarian reforms on poverty alleviation in Joubertina. Purposive sampling method (non-probability sampling) was carried out mainly on two groups of people, land reform beneficiary in Jay Dee Rovon and non-beneficiary in Mon Desire. Moreover, the stratified random sampling method was also applied in Jay Dee Rovon to choose a sample of 60 households from 129 land reform beneficiaries in Jay Dee Rovon and simple random sample of 60 applied to Mon Desire household subsistence. Binary Logistic Regression model was used to test factors that influenced beneficiary on level of production. Results indicated that age and farming experience were significant variables. Age had a negative coefficient value, meaning an increase in age was less likely to cause beneficiary to produce at commercial level. Descriptive statistics revealed that farming activities in the study areas seems to be performed mostly by relatively medium age people followed by younger people and lastly by the older people. Moreover, farming experience with positive coefficient revealed that it is highly likely to influence the beneficiary to produce at commercial for marketing. The older the farmer the more the experience s/he had in farming activities. However, descriptive revealed, medium and young age people with little knowledge tend to be more active than older people on farming activities but on the other hand they are more capable of carrying out physical activities. The results revealed that land reform beneficiaries likely to influence the level of production for marketing while non-beneficiaries produce for home consumption and little for sale in local market. An improvement on yield results an increase on income and thus leading to a change in ownership of household’s durable assets. An increase in yield also indirectly results employment recreation, increasing real wage and improve farm income thus leading to poverty reduction in JDR as compare to MD. The study recommends that the government should also assist non-beneficiaries in MD with agricultural infrastructure to improve their level of production and food security at household level.
- Full Text:
- Date Issued: 2014
- Authors: Mqikela, Ntombozuko
- Date: 2014
- Subjects: Land reform -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11207 , http://hdl.handle.net/10353/d1016070 , Land reform -- South Africa -- Eastern Cape , Agricultural extension work -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Description: The broad objective of the study is to investigate the impact of Land and Agrarian reforms on poverty alleviation in Joubertina. Purposive sampling method (non-probability sampling) was carried out mainly on two groups of people, land reform beneficiary in Jay Dee Rovon and non-beneficiary in Mon Desire. Moreover, the stratified random sampling method was also applied in Jay Dee Rovon to choose a sample of 60 households from 129 land reform beneficiaries in Jay Dee Rovon and simple random sample of 60 applied to Mon Desire household subsistence. Binary Logistic Regression model was used to test factors that influenced beneficiary on level of production. Results indicated that age and farming experience were significant variables. Age had a negative coefficient value, meaning an increase in age was less likely to cause beneficiary to produce at commercial level. Descriptive statistics revealed that farming activities in the study areas seems to be performed mostly by relatively medium age people followed by younger people and lastly by the older people. Moreover, farming experience with positive coefficient revealed that it is highly likely to influence the beneficiary to produce at commercial for marketing. The older the farmer the more the experience s/he had in farming activities. However, descriptive revealed, medium and young age people with little knowledge tend to be more active than older people on farming activities but on the other hand they are more capable of carrying out physical activities. The results revealed that land reform beneficiaries likely to influence the level of production for marketing while non-beneficiaries produce for home consumption and little for sale in local market. An improvement on yield results an increase on income and thus leading to a change in ownership of household’s durable assets. An increase in yield also indirectly results employment recreation, increasing real wage and improve farm income thus leading to poverty reduction in JDR as compare to MD. The study recommends that the government should also assist non-beneficiaries in MD with agricultural infrastructure to improve their level of production and food security at household level.
- Full Text:
- Date Issued: 2014
Towards the modeling of indigenous poultry production in the Eastern Cape Province, South Africa: characterization and extension evaluation for poverty reduction
- Yusuf, Shehu Folaranmi Gbolahan Shehu
- Authors: Yusuf, Shehu Folaranmi Gbolahan Shehu
- Date: 2014
- Subjects: Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Agricultural Economics)
- Identifier: vital:11223 , http://hdl.handle.net/10353/d1019833 , Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Description: Poverty remains a critical issue mostly in the rural South Africa. Various initiatives, policies and programs have been enacted by the government with attempting to reduce poverty at the national and provincial levels; poverty is yet to be abated. The target of the Millennium Development Goal 1 (MDG1) of halving poverty by the year 2015 notwithstanding, poverty remains a threat to quality livelihoods. Agriculture has continued to be one of the pillars of government efforts to address poverty. However, in livestock production interventions, efforts of government had largely been on cattle, sheep, goats, pigs and exotic poultry with little attention being given to indigenous poultry production (IPP). This study explores the option of using IPP to address rural poverty by capitalizing on its minimal inputs while recognizing its prevalence in a variety of households. The study addresses the characterization of the IPP from the perspectives of housing, feeding, healthcare management, breeding and marketing options.Skill competencies of the indigenous poultry farmers (IPFs) and the Agricultural Development Technicians (ADTs) were examined. This study reviewed poultry models in different parts of the world with special attention to Africa. The human resource development program of the department of rural development and agrarian reform was discussed. The study employed the use of multi-methods approach, the quantitative and qualitative research methodologies. Descriptive statistical analysis, frequent count, percentage, means, standard deviation, chisquare, and principal component analysis was used in the quantitative data analysis while the “open social system” was used for the qualitative methodology. Findings revealed that IPFs face some challenges among which are, the poor housing that exposed the birds to inclement weather, predator attacks and stock theft, high mortality of chicks after hatching and expensive feed for the flock. The IPFs showed competencies in nine skill items that included ability to identify chicken predators (x=3.92) and high yielding chickens (x=3.79); control of predators(x=3.77); methods of using ethno veterinary drugs to treat chicken diseases and pests (x=3.72), and identify signs of diseases (x=3.69), among others. However, the ADTs did not show any competency in any of the 32 skills items. The principal component analysis with Varimax rotation was performed to ascertain the dimensionality of the measures. Six factors with eigen value of >1, which accounted for 77.317% were extracted, with each factor loading ranging from 0.523 to 0.93. Factor loading after rotation that emerged on the same component was described; as brooding, shelter and care of the chicks; predators and healthcare; hygiene and litter management; feeds and feeding stuff; and record keeping and marketing. The findings on the human resource development revealed that staff meetings were the most common method of capacity development. This was followed by in-service-training, formal study, workshop, and on the job training. The farmers’ field school and study tours were sparingly used. However, respondents were in favor of on-site training, staff meetings, formal study and in-service training. The findings on the appropriate model suggest a theoretical indigenous poultry production model (IPPM) for the Eastern Cape Province (ECP). The “open social system” was used to develop a framework for an indigenous poultry cooperative society (to be known as Abafuyi Benkukhu Zemveli [ABZ]). This was meant to create a binding force for capacity development, a strong economic foundation through equity contributions, creation of marketing channels, and the development of a concept of ‘‘our own'' product in the market. Lastly, the study offers options for a training program that would accommodate the new initiatives, with a strong capacity development training approach. In this context, the study advocates for institutional support for the IPFs and the incorporation of indigenous poultry in the curriculum of the agricultural training programs at higher education institutions in South Africa.
- Full Text:
- Date Issued: 2014
- Authors: Yusuf, Shehu Folaranmi Gbolahan Shehu
- Date: 2014
- Subjects: Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Agricultural Economics)
- Identifier: vital:11223 , http://hdl.handle.net/10353/d1019833 , Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Description: Poverty remains a critical issue mostly in the rural South Africa. Various initiatives, policies and programs have been enacted by the government with attempting to reduce poverty at the national and provincial levels; poverty is yet to be abated. The target of the Millennium Development Goal 1 (MDG1) of halving poverty by the year 2015 notwithstanding, poverty remains a threat to quality livelihoods. Agriculture has continued to be one of the pillars of government efforts to address poverty. However, in livestock production interventions, efforts of government had largely been on cattle, sheep, goats, pigs and exotic poultry with little attention being given to indigenous poultry production (IPP). This study explores the option of using IPP to address rural poverty by capitalizing on its minimal inputs while recognizing its prevalence in a variety of households. The study addresses the characterization of the IPP from the perspectives of housing, feeding, healthcare management, breeding and marketing options.Skill competencies of the indigenous poultry farmers (IPFs) and the Agricultural Development Technicians (ADTs) were examined. This study reviewed poultry models in different parts of the world with special attention to Africa. The human resource development program of the department of rural development and agrarian reform was discussed. The study employed the use of multi-methods approach, the quantitative and qualitative research methodologies. Descriptive statistical analysis, frequent count, percentage, means, standard deviation, chisquare, and principal component analysis was used in the quantitative data analysis while the “open social system” was used for the qualitative methodology. Findings revealed that IPFs face some challenges among which are, the poor housing that exposed the birds to inclement weather, predator attacks and stock theft, high mortality of chicks after hatching and expensive feed for the flock. The IPFs showed competencies in nine skill items that included ability to identify chicken predators (x=3.92) and high yielding chickens (x=3.79); control of predators(x=3.77); methods of using ethno veterinary drugs to treat chicken diseases and pests (x=3.72), and identify signs of diseases (x=3.69), among others. However, the ADTs did not show any competency in any of the 32 skills items. The principal component analysis with Varimax rotation was performed to ascertain the dimensionality of the measures. Six factors with eigen value of >1, which accounted for 77.317% were extracted, with each factor loading ranging from 0.523 to 0.93. Factor loading after rotation that emerged on the same component was described; as brooding, shelter and care of the chicks; predators and healthcare; hygiene and litter management; feeds and feeding stuff; and record keeping and marketing. The findings on the human resource development revealed that staff meetings were the most common method of capacity development. This was followed by in-service-training, formal study, workshop, and on the job training. The farmers’ field school and study tours were sparingly used. However, respondents were in favor of on-site training, staff meetings, formal study and in-service training. The findings on the appropriate model suggest a theoretical indigenous poultry production model (IPPM) for the Eastern Cape Province (ECP). The “open social system” was used to develop a framework for an indigenous poultry cooperative society (to be known as Abafuyi Benkukhu Zemveli [ABZ]). This was meant to create a binding force for capacity development, a strong economic foundation through equity contributions, creation of marketing channels, and the development of a concept of ‘‘our own'' product in the market. Lastly, the study offers options for a training program that would accommodate the new initiatives, with a strong capacity development training approach. In this context, the study advocates for institutional support for the IPFs and the incorporation of indigenous poultry in the curriculum of the agricultural training programs at higher education institutions in South Africa.
- Full Text:
- Date Issued: 2014
Water footprint of growing vegetables in selected smallholder irrigation schemes in South Africa
- Authors: Nyambo, Patrick
- Date: 2014
- Subjects: Water consumption , Irrigation efficiency , Rural development
- Language: English
- Type: Thesis , Masters , MSc Agric (Soil Science)
- Identifier: vital:11964 , http://hdl.handle.net/10353/d1019775 , Water consumption , Irrigation efficiency , Rural development
- Description: Knowledge of water use, through water foot printing (WF) in smallholder agriculture crop production is the key to the global fight against poverty, achievement of food security and sustainability within the world’s rural community. Water footprint of a crop can be defined as the volume of fresh water used to produce a certain crop in all the steps in the production line. This study, therefore aimed at contributing towards improvements in rural livelihoods by raising awareness of the increased productive use of green, blue and grey water in smallholder agriculture in South Africa. This was done through determination of water footprints of five vegetable crops, i.e. potatoes (Solanum tuberosum), tomatoes (Solanum lycopersicum), dry beans (Phaseolus vulgaris), cabbage (Brassica oleracea spp) and spinach (Spinacia oleracea) in the 2000-2013 period. Quantification of water footprints has been done worldwide but, in South Africa (SA) focus has mostly been on the industrial and domestic sector. Water footprint assessment framework, was used to estimate the full impact of vegetable production on water resources at Zanyokwe, Thabina and Tugela Ferry irrigation schemes as case studies. The CROPWAT@ model was used to calculate crop evapotranspiration, differentiating green and blue water. Local climatic data were obtained from SA weather services, while the crop and soil parameters were obtained from the FAO data base. Nitrogen was considered the main pollutant hence its use in the grey water footprint calculation. Generally, Thabina irrigation scheme had the highest water footprint, followed by Tugela Ferry irrigation scheme whilst Zanyokwe irrigation scheme had the lowest. Green beans had the highest water footprint at all the three irrigation schemes with Thabina irrigation scheme having the highest (3535.1 m3/ton). For Tugela Ferry irrigation scheme, the calculated WF was 2753 m3/ton whilst the lowest was observed at ZIS i.e. 2407.6 m3/ton. Cabbage had the lowest water footprint. The highest water footprint for growing cabbage was 254.5 m3/ton in TFIS, 223.1 m3/ton in TIS and the lowest was 217.8 m3/ton in ZIS. The differences observed in the WF of a crop at each scheme maybe attributed to the differences management, weather and environmental characteristics, in the three locations. Moreover, the needs for ET are related to soil type and plant growth, and primarily depend on crop development and climatic factors which are closely related to climatic demands. The grey water footprint was calculated using the recommended fertilizer application rates for all the three sites. Green beans had the highest WFgrey i.e. 373 m3/ton and the lowest was cabbage with 37 m3/ton. Potato, spinach and tomatoes had 156 m3/ton, 214 m3/ton and 132 m3/ton, respectively. Grey water footprint in this study was higher as compared to other studies, possibly because of the high rates of nitrogen fertilizers used in the calculations and the low yields farmers get. Compared with estimates from other studies, the water footprints of vegetable production within smallholder irrigation schemes was relatively high. There is therefore, a need to focus on crop management and tillage practices that will help in increasing yield while minimizing water usage.
- Full Text:
- Date Issued: 2014
- Authors: Nyambo, Patrick
- Date: 2014
- Subjects: Water consumption , Irrigation efficiency , Rural development
- Language: English
- Type: Thesis , Masters , MSc Agric (Soil Science)
- Identifier: vital:11964 , http://hdl.handle.net/10353/d1019775 , Water consumption , Irrigation efficiency , Rural development
- Description: Knowledge of water use, through water foot printing (WF) in smallholder agriculture crop production is the key to the global fight against poverty, achievement of food security and sustainability within the world’s rural community. Water footprint of a crop can be defined as the volume of fresh water used to produce a certain crop in all the steps in the production line. This study, therefore aimed at contributing towards improvements in rural livelihoods by raising awareness of the increased productive use of green, blue and grey water in smallholder agriculture in South Africa. This was done through determination of water footprints of five vegetable crops, i.e. potatoes (Solanum tuberosum), tomatoes (Solanum lycopersicum), dry beans (Phaseolus vulgaris), cabbage (Brassica oleracea spp) and spinach (Spinacia oleracea) in the 2000-2013 period. Quantification of water footprints has been done worldwide but, in South Africa (SA) focus has mostly been on the industrial and domestic sector. Water footprint assessment framework, was used to estimate the full impact of vegetable production on water resources at Zanyokwe, Thabina and Tugela Ferry irrigation schemes as case studies. The CROPWAT@ model was used to calculate crop evapotranspiration, differentiating green and blue water. Local climatic data were obtained from SA weather services, while the crop and soil parameters were obtained from the FAO data base. Nitrogen was considered the main pollutant hence its use in the grey water footprint calculation. Generally, Thabina irrigation scheme had the highest water footprint, followed by Tugela Ferry irrigation scheme whilst Zanyokwe irrigation scheme had the lowest. Green beans had the highest water footprint at all the three irrigation schemes with Thabina irrigation scheme having the highest (3535.1 m3/ton). For Tugela Ferry irrigation scheme, the calculated WF was 2753 m3/ton whilst the lowest was observed at ZIS i.e. 2407.6 m3/ton. Cabbage had the lowest water footprint. The highest water footprint for growing cabbage was 254.5 m3/ton in TFIS, 223.1 m3/ton in TIS and the lowest was 217.8 m3/ton in ZIS. The differences observed in the WF of a crop at each scheme maybe attributed to the differences management, weather and environmental characteristics, in the three locations. Moreover, the needs for ET are related to soil type and plant growth, and primarily depend on crop development and climatic factors which are closely related to climatic demands. The grey water footprint was calculated using the recommended fertilizer application rates for all the three sites. Green beans had the highest WFgrey i.e. 373 m3/ton and the lowest was cabbage with 37 m3/ton. Potato, spinach and tomatoes had 156 m3/ton, 214 m3/ton and 132 m3/ton, respectively. Grey water footprint in this study was higher as compared to other studies, possibly because of the high rates of nitrogen fertilizers used in the calculations and the low yields farmers get. Compared with estimates from other studies, the water footprints of vegetable production within smallholder irrigation schemes was relatively high. There is therefore, a need to focus on crop management and tillage practices that will help in increasing yield while minimizing water usage.
- Full Text:
- Date Issued: 2014
Wild vegetables of the Eastern Cape of South Africa: the nutritional value and domestication of solanum nigrum l
- Authors: Bvenura, Callistus
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Ethnobotany)
- Identifier: vital:11885 , http://hdl.handle.net/10353/d1015514
- Description: An ethnobotanical survey was conducted in Alice and Willowvale in the Nkonkobe and Mbashe municipalities of the Eastern Cape Province, South Africa to identify and document wild vegetables growing in the areas. The survey documented 22 vegetable species belonging to 12 different families. The Amaryllidaceae, Amaranthaceae, Apiaceae, Asteraceae, Caryophyllaceae, Chenopodiaceae, Convolvulaceae, Cruciferae, Cucurbitaceaea, Euphorbiaceae, Tiliaceae, Solanaceae, Polygonaceae and Urticaceae were the families that were recorded. The species were Tulbaghia violacea Harv., Amaranthus blitoides S., Amaranthus blitum L., Amaranthus hybridus L., Centella coriacea Nannfd., Bidens pilosa L, Cotula heterocarpa DC., Sonchus oleraceus L., Galinsoga parviflora Cav., Taraxacum officinale Weber, Hypochaeris radicata L., Stellaria media L., Chenopodium album L., Chenopodium murale L., Ipomoea batatas L., Sisymbrium thellungii O. Schulz, Cucurbita pepo L., Rumex crispus L., Acalypha virginica L., Nicandra physalodes L., Physalis peruviana L., Solanum nigrum L., Urtica urens L. and Corchorus olitorius L. About 27 % of the wild vegetables were native to South Africa and about 45 % were also used as medicinal plants in the areas. Sun drying was the most common method of preserving the wild vegetables for the off season months. This study also revealed that, men and the younger generation knew less about wild vegetables than the women. The study also revealed a loss of knowledge of wild vegetables and their use by the rural dwellers who are more in favour of the exotic types such as spinach and cabbage.
- Full Text:
- Date Issued: 2014
- Authors: Bvenura, Callistus
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Ethnobotany)
- Identifier: vital:11885 , http://hdl.handle.net/10353/d1015514
- Description: An ethnobotanical survey was conducted in Alice and Willowvale in the Nkonkobe and Mbashe municipalities of the Eastern Cape Province, South Africa to identify and document wild vegetables growing in the areas. The survey documented 22 vegetable species belonging to 12 different families. The Amaryllidaceae, Amaranthaceae, Apiaceae, Asteraceae, Caryophyllaceae, Chenopodiaceae, Convolvulaceae, Cruciferae, Cucurbitaceaea, Euphorbiaceae, Tiliaceae, Solanaceae, Polygonaceae and Urticaceae were the families that were recorded. The species were Tulbaghia violacea Harv., Amaranthus blitoides S., Amaranthus blitum L., Amaranthus hybridus L., Centella coriacea Nannfd., Bidens pilosa L, Cotula heterocarpa DC., Sonchus oleraceus L., Galinsoga parviflora Cav., Taraxacum officinale Weber, Hypochaeris radicata L., Stellaria media L., Chenopodium album L., Chenopodium murale L., Ipomoea batatas L., Sisymbrium thellungii O. Schulz, Cucurbita pepo L., Rumex crispus L., Acalypha virginica L., Nicandra physalodes L., Physalis peruviana L., Solanum nigrum L., Urtica urens L. and Corchorus olitorius L. About 27 % of the wild vegetables were native to South Africa and about 45 % were also used as medicinal plants in the areas. Sun drying was the most common method of preserving the wild vegetables for the off season months. This study also revealed that, men and the younger generation knew less about wild vegetables than the women. The study also revealed a loss of knowledge of wild vegetables and their use by the rural dwellers who are more in favour of the exotic types such as spinach and cabbage.
- Full Text:
- Date Issued: 2014
‘Student life’ discourse and the perception of risk for HIV infection among undergraduate nursing students, at a university, Eastern Cape Province, South Africa
- Authors: Mnwana, Sindiswa Millicent
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11922 , http://hdl.handle.net/10353/d1019830
- Description: There is evidence that the HIV prevalence rates among South African university students remains low at 3.4 %. However, the vulnerability of young people to HIV/AIDS continues to be a serious concern as the prevalence of sexual risk behaviour among students in South African universities is reported to reach 68% in heterosexual relationships. Some analysts argue that so far little is known about the influence of the university culture (the so called “student life”) in this behaviour. The purpose of this study was to explore the perceptions of the risk for HIV infection amongst undergraduate nursing students at an institution of higher learning (university) in East London, Eastern Cape. More specifically, the study examined the ways in which the ‘student life’ discourse functions to influence students’ perceptions of the risk to HIV infection at the selected institution of higher learning. An explorative and descriptive qualitative design was used. The purposive sampling technique was used to select participants. In total, 12 one to one interviews and four focus group discussions (n=35) were conducted. An interview guide was used and a voice recorder to record interviews. Through in-depth interviews and focus group discussions, the research sought to provide insight into the perceptions of risk for HIV infection. The data were analysed using thematic analysis and the themes identified formed the basis for discussion in this study. Among the key findings, that emerged from this study was that knowledge about potential risks to HIV/AIDS did not seem to influence the general sexual behaviour of students. A majority of the participants, 90% that were interviewed individually perceived themselves to be at “little or no” risk of contracting HIV/AIDS despite the high prevalence of HIV risk indicators among them. One of the main findings was that the students’ values that they bring from home were seriously challenged by the student life when they arrived at the university. Therefore in this regard undergraduate nursing students should be equipped by the university with aspects of sexual behaviour such as sexual negotiation and sexual decision making. This would equip them with the necessary skills to resist peer pressure.
- Full Text:
- Date Issued: 2014
- Authors: Mnwana, Sindiswa Millicent
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11922 , http://hdl.handle.net/10353/d1019830
- Description: There is evidence that the HIV prevalence rates among South African university students remains low at 3.4 %. However, the vulnerability of young people to HIV/AIDS continues to be a serious concern as the prevalence of sexual risk behaviour among students in South African universities is reported to reach 68% in heterosexual relationships. Some analysts argue that so far little is known about the influence of the university culture (the so called “student life”) in this behaviour. The purpose of this study was to explore the perceptions of the risk for HIV infection amongst undergraduate nursing students at an institution of higher learning (university) in East London, Eastern Cape. More specifically, the study examined the ways in which the ‘student life’ discourse functions to influence students’ perceptions of the risk to HIV infection at the selected institution of higher learning. An explorative and descriptive qualitative design was used. The purposive sampling technique was used to select participants. In total, 12 one to one interviews and four focus group discussions (n=35) were conducted. An interview guide was used and a voice recorder to record interviews. Through in-depth interviews and focus group discussions, the research sought to provide insight into the perceptions of risk for HIV infection. The data were analysed using thematic analysis and the themes identified formed the basis for discussion in this study. Among the key findings, that emerged from this study was that knowledge about potential risks to HIV/AIDS did not seem to influence the general sexual behaviour of students. A majority of the participants, 90% that were interviewed individually perceived themselves to be at “little or no” risk of contracting HIV/AIDS despite the high prevalence of HIV risk indicators among them. One of the main findings was that the students’ values that they bring from home were seriously challenged by the student life when they arrived at the university. Therefore in this regard undergraduate nursing students should be equipped by the university with aspects of sexual behaviour such as sexual negotiation and sexual decision making. This would equip them with the necessary skills to resist peer pressure.
- Full Text:
- Date Issued: 2014