Stratigraphy and sedimentology of the Msikaba formation in KwaZulu Natal South Coast, South Africa
- Authors: Busakwe, Nolukholo Sinovuyo
- Date: 2015
- Subjects: Geology, Stratigraphic Sedimentology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2501 , vital:27877
- Description: The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.
- Full Text:
- Date Issued: 2015
- Authors: Busakwe, Nolukholo Sinovuyo
- Date: 2015
- Subjects: Geology, Stratigraphic Sedimentology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2501 , vital:27877
- Description: The Msikaba Formation is a Late Devonian fluvial and marine succession which outcrops from Hibberdene to Port Edward along the south coast of KwaZulu-Natal Province, South Africa. The Formation is composed of brownish conglomerate at the bottom and white-greyish quartz arenite sequence in the middle and mixed quartz-arenite with feldspathic sandstone in the upper sequence. Previous studies put more emphasis on the correlation of Msikaba Formation with the Natal Group and Cape Supergroup, whereas this study revised the stratigraphy, and also put new insight on the petrography, sedimentary facies, depositional environments and diagenesis of the Formation. The total stratigraphic section attains a thickness of 184 m at Margate area and 186 m at Port Edward area. The stratigraphy of Msikaba Formation is well exposed on the outcrops along the KwaZulu-Natal coastline. The stratigraphy is subdivided into 4 new members along Margate to Shelly beach section; namely Manaba Member, Uvongo Member, Mhlangeni Member and Shelly Beach Member from bottom upward. Twelve sedimentary facies were identified and the sedimentary facies were integrated into 4 facies association: Facies association 1 (Gmm+Sm) represents braided fluvial deposits, Facies association 2 (Gcm+St+Sp+Sl+Shb) represents tidal channel and tidal flat deposit, Facies association 3 (St+Sp+Sr+Sl) is result of shallow marine deposit and Facies association 4 (Sp+Sl+St+Sm) is a mixed marine and fluvial deposit. Each facies association represents a specific stratigraphic unit and were deposited in a specific sedimentary environment. Grain size analysis was conducted on seventeen thin sections and 500 grains were counted from each thin section. The sandstone grain size parameters of mean, sorting, skewness and kurtosis fell under the average of 0.75, 0.78, 0.4 and 1.2φ respectively. The results show that most of the grain size are coarse to medium grained throughout the study areas and sorting of the sandstones are moderate to poorly sorted. The cumulative frequency diagrams and bivariate plots show positive skewness and negative kurtosis, which indicate a high hydrodynamic environment. Modal composition analysis and petrography studies show that detrital components of the Msikaba Formation are dominated by monocrystalline quartz, feldspar (mostly K-feldspar) and lithic fragments of igneous and metamorphic rocks. The sandstones could be classified as quartz arenite, sub-arkosic sandstone and feldspathic litharenite; and the provenance analysis indicates that the sandstones were derived from craton interior, recycled or quartzose recycled sources which may derived from weathering and erosion of igneous and metamorphic rocks. Diagenetic processes of the Msikaba Formation have been passed through early, mid- and late diagenetic stages. Cementation, mineral conversion and compaction affect early diagenetic stage; authigenic minerals, quartz and feldspar overgrowth are presented in mid-diagenetic stage, whereas recrystallization, replacement, deformation and dissolution have been strongly affected late diagenetic stage. Microscopy, XRD and SEM-EDX studies have identified five types of cements including smectite clay, kaolinite, hematite, quartz and feldspar cements. Quartz cement, pore-filling and pore-lining clay are the major type of cements in the Msikaba Formation. Based on the lithology, sedimentary structure and facies variations, the Manaba Member was most probably deposited in a braided fluvial environment, the Uvongo Member was deposited in a tidal channel environment, the Mhlangeni Member was formed in shallow marine storm-influenced environment, whereas the Shelly Beach Member was represented mixed marine and fluvial environment. The sequence stratigraphy of Msikaba Formation constitutes a transgressive sequence from Manaba Member to Uvongo Member, whereas it ended as a regressive sequence from Mhlangeni Member to Shelly beach Member. The Msikaba Formation shows major differences with the Natal Group and Table Mountain Group (Cape Supergroup) in the lithology, stratigraphic sequence, sedimentary structures, facies system, palaeocurrent styles, fossil contents and depositional environments, which demonstrate that they are not the equivalent stratigraphic unit. Therefore, the Msikaba Formation is a separate, younger stratigraphic unit, and cannot correlate with the Natal Group and Table Mountain Group as suggested by previous researchers.
- Full Text:
- Date Issued: 2015
Synthesis and characterization of Ru(II) phenyl-3-indenylidene olefin metathesis type complexes
- Authors: Yalezo, Ntsikelelo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11351 , http://hdl.handle.net/10353/d1021128
- Description: In this study, a series of Ru(II) phenyl-3-indenylidene complexes with general formula of [RuCl2(NHC)(Ind)(L)] (where L= triphenylphosphine, pyridine and NHC = five different types of N-heterocyclic carbene ligands), have been synthesized and characterized using FT-IR, UV-Vis, elementally analysis and melting/decomposition point. The N,N’-diarylimidazolinium chlorides have been used as N-heterocyclic carbene precursors and were synthesized from their corresponding N,N’-diarylformamidines and further characterized using 1H-NMR, 13C-NMR, FTIR and melting point determination. The infrared spectra of the N,N’-diarylimidazolinium chlorides show a quaternary nature (R2N=C+) with broad vibration band in region 3300-3400 cm-1. The disappearance of this vibration band in the infrared spectra of the ruthenium(II) complexes was used to confirm the coordination of the ligand to the ruthenium ions. The percentage analysis of carbon, hydrogen and nitrogen obtained corresponded with the calculated percentages of these atoms in the complexes with the slight difference of less than 1%. The electronic spectra of the complexes show three distinct absorption bands. The two bands are due to intraligand charge transfers transition assigned to π→π*, n→π* and third band is due to d-d transition, signifying the presence of the metal ion. The synthesized Ru(II) complexes did not show any of melting, however a change in colour was observed signifying the decomposition of the complexes.
- Full Text:
- Date Issued: 2015
- Authors: Yalezo, Ntsikelelo
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11351 , http://hdl.handle.net/10353/d1021128
- Description: In this study, a series of Ru(II) phenyl-3-indenylidene complexes with general formula of [RuCl2(NHC)(Ind)(L)] (where L= triphenylphosphine, pyridine and NHC = five different types of N-heterocyclic carbene ligands), have been synthesized and characterized using FT-IR, UV-Vis, elementally analysis and melting/decomposition point. The N,N’-diarylimidazolinium chlorides have been used as N-heterocyclic carbene precursors and were synthesized from their corresponding N,N’-diarylformamidines and further characterized using 1H-NMR, 13C-NMR, FTIR and melting point determination. The infrared spectra of the N,N’-diarylimidazolinium chlorides show a quaternary nature (R2N=C+) with broad vibration band in region 3300-3400 cm-1. The disappearance of this vibration band in the infrared spectra of the ruthenium(II) complexes was used to confirm the coordination of the ligand to the ruthenium ions. The percentage analysis of carbon, hydrogen and nitrogen obtained corresponded with the calculated percentages of these atoms in the complexes with the slight difference of less than 1%. The electronic spectra of the complexes show three distinct absorption bands. The two bands are due to intraligand charge transfers transition assigned to π→π*, n→π* and third band is due to d-d transition, signifying the presence of the metal ion. The synthesized Ru(II) complexes did not show any of melting, however a change in colour was observed signifying the decomposition of the complexes.
- Full Text:
- Date Issued: 2015
Synthesis, characterisation and evaluation of functionalized Lignocelluloses-clay nanocomposites for organic pollutant removal from water
- Authors: Mafukidze, Donovan M
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11356 , http://hdl.handle.net/10353/d1021296
- Description: PMPSgLig-NaMMT nanocomposites were prepared from methacryloxypropyltrimethoxysilane (MPS), lignocellulose and montmorillonite clay. The potential enhancement of organic pollutant adsorption capabilities of PMPSgLig-NaMMT nanocomposite from water through functionalization was investigated. PMPSgLig-NaMMT was functionalized by esterification and etherification using different methods so as to increase the surface hydrophobicity of the material and hence improve its compatibility with the target pollutants. Specific chemical routes specially tailored for PMPSgLig-NaMMT were established for functionalization mostly based on the common esterification (Fischer esterification) and etherification (Williamson‟s etherification) reactions. In the functionalization methods, factors such as pH environment, nanocomposite composition, nature of functionalization moiety, and use of or absence of solvents and their variations were studied. FT-IR, XRD, SEM and TGA were used to characterize the synthesized and functionalized nanoadsorbents. The techniques showed successful functionalization via esterification and etherification methods albeit to different extents, with clear retention of the material‟s original structure though there were signs of degradation with some methods. Characterization was supported by adsorption studies to validate implications and draw conclusions. The use of 1,10-phenathroline as a model organic pollutant in water in the adsorption studies showed that adsorbents conformed to monolayer adsorption following pseudo-second order kinetics for adsorption of organic pollutants accurately represented. Most importantly the studies revealed the significant impact of the nanocomposite composition on the overall absorbent performance. Adsorption studies also showed that functionalization via esterification methods gave rise to better adsorbents.
- Full Text:
- Date Issued: 2015
- Authors: Mafukidze, Donovan M
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11356 , http://hdl.handle.net/10353/d1021296
- Description: PMPSgLig-NaMMT nanocomposites were prepared from methacryloxypropyltrimethoxysilane (MPS), lignocellulose and montmorillonite clay. The potential enhancement of organic pollutant adsorption capabilities of PMPSgLig-NaMMT nanocomposite from water through functionalization was investigated. PMPSgLig-NaMMT was functionalized by esterification and etherification using different methods so as to increase the surface hydrophobicity of the material and hence improve its compatibility with the target pollutants. Specific chemical routes specially tailored for PMPSgLig-NaMMT were established for functionalization mostly based on the common esterification (Fischer esterification) and etherification (Williamson‟s etherification) reactions. In the functionalization methods, factors such as pH environment, nanocomposite composition, nature of functionalization moiety, and use of or absence of solvents and their variations were studied. FT-IR, XRD, SEM and TGA were used to characterize the synthesized and functionalized nanoadsorbents. The techniques showed successful functionalization via esterification and etherification methods albeit to different extents, with clear retention of the material‟s original structure though there were signs of degradation with some methods. Characterization was supported by adsorption studies to validate implications and draw conclusions. The use of 1,10-phenathroline as a model organic pollutant in water in the adsorption studies showed that adsorbents conformed to monolayer adsorption following pseudo-second order kinetics for adsorption of organic pollutants accurately represented. Most importantly the studies revealed the significant impact of the nanocomposite composition on the overall absorbent performance. Adsorption studies also showed that functionalization via esterification methods gave rise to better adsorbents.
- Full Text:
- Date Issued: 2015
Synthesis, characterization & application of visible light responsive nitrogen doped Tio2 and copolymer-grafted asymmetric membranes with ozonolysis for water treatment
- Authors: Mungondori, Henry H
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11350 , http://hdl.handle.net/10353/d1020257
- Description: The use of titanium dioxide for the photo-catalytic removal of organic, inorganic, and microbial pollutants from natural water and wastewater has been considered a very promising technique. The aim of this study was to prepare nitrogen doped titanium dioxide, immobilize it on asymmetric polymeric membranes of poly (methacrylic acid) grafted onto poly (vinylidene difluoride) (PVDF) blended with poly (acrylonitrile) (PAN), and evaluate the photo-catalytic, antimicrobial, and antifouling properties of the membranes. Nitrogen doped titanium dioxide (N-TiO2) nano-particles were prepared by a low temperature sol gel synthesis technique. The modification of TiO2 with nitrogen allows photo-sensitization of the photo-catalyst towards visible light utilization. The N-TiO2 nano-particles were characterized by fourier transform infrared spectroscopy (FT-IR), scanning x-ray photoelectron spectroscopy (SXPS), X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), Brunauer Emmett Teller (BET) surface area analysis, and transmission electron microscopy (TEM). The characterizations revealed the presence of the expected functional groups and confirmed successful doping and that the product was visible light responsive. Novel poly (methacrylic acid) grafted onto poly (vinylidene difluoride)/ poly (acrylonitrile) (PMAA-g-PVDF/ PAN) asymmetric membranes were prepared by the dry-wet phase inversion technique. The poly (methacrylic acid) (PMAA) side chains where grafted onto an activated PVDF backbone by reversible addition fragmentation chain transfer (RAFT) polymerization. The photo-catalytic membranes were generated by blending N-TiO2 with the polymer solution before casting the membranes. The membranes were characterized by FT-IR, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). FT-IR and NMR analyses confirmed successful grafting of MAA chains onto PVDF while SEM confirmed the successful preparation of membranes with asymmetric structure. The efficacy of the photo-catalytic asymmetric membranes was evaluated on the removal of herbicides from synthetic water. Bentazon was easily degraded while atrazine and paraquat were recalcitrant and proved difficult to degrade. The best results were observed with 3 % N-TiO2-PMAA-g-PVDF/ PAN asymmetric membranes on the photo-degradation of bentazon, atrazine and paraquat in water. Significant enhancement in the photo-degradation of the three herbicides was observed when photo-catalytic degradation was coupled with ozonation. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of a degradation by-product during the photo-catalytic degradation of bentazon. The photo-catalytic membranes were also evaluated on the photo-catalytic reduction of heavy metals Pb2+ and Fe3+ in water, and the best results were obtained using 1 % N-TiO2-PMAA-g-PVDF/ PAN and 1 % N-TiO2-PAN asymmetric membranes. All prepared photo-catalytic membranes where capable of completely inactivating E. coli ATCC 8739 within 120 minutes of exposure and inactivation rate increased with increasing N-TiO2 photo-catalyst loading. However, there was an indication from the results obtained that N-TiO2 supported on PMAA-g-PVDF/ PAN showed a higher inactivation rate of E. coli ATCC 8739 compared to N-TiO2-PAN and N-TiO2-PVDF membranes. The 1 % N-TiO2-PMAA-g-PVDF/ PAN membranes gave the highest pure water flux (421.83 L/m2h). This increase (PVDF = 30.50 L/m2h, PAN = 73.85 L/m2h) in pure water flux is owedb to PMAA grafting as well as addition of N-TiO2. These modifications resulted in an increased membrane surface hydrophilicity, which promoted permeation of pure water through the membrane structure. A high bovine serum albumin (BSA) rejection (76.5 %) was noted and can be attributed to steric hindrance brought about by PMAA side chains which prevented the bulky BSA molecules from attaching to the membrane surface for PMAA-g-PVDF/ PAN membranes. However, the supporting porous sub-layer of an asymmetric membrane seemed to play a very important role in the overall permeability of a membrane. PVDF membranes are highly hydrophobic hence they gave a very low pure water flux.
- Full Text:
- Date Issued: 2015
- Authors: Mungondori, Henry H
- Date: 2015
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: vital:11350 , http://hdl.handle.net/10353/d1020257
- Description: The use of titanium dioxide for the photo-catalytic removal of organic, inorganic, and microbial pollutants from natural water and wastewater has been considered a very promising technique. The aim of this study was to prepare nitrogen doped titanium dioxide, immobilize it on asymmetric polymeric membranes of poly (methacrylic acid) grafted onto poly (vinylidene difluoride) (PVDF) blended with poly (acrylonitrile) (PAN), and evaluate the photo-catalytic, antimicrobial, and antifouling properties of the membranes. Nitrogen doped titanium dioxide (N-TiO2) nano-particles were prepared by a low temperature sol gel synthesis technique. The modification of TiO2 with nitrogen allows photo-sensitization of the photo-catalyst towards visible light utilization. The N-TiO2 nano-particles were characterized by fourier transform infrared spectroscopy (FT-IR), scanning x-ray photoelectron spectroscopy (SXPS), X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy (DRS), Brunauer Emmett Teller (BET) surface area analysis, and transmission electron microscopy (TEM). The characterizations revealed the presence of the expected functional groups and confirmed successful doping and that the product was visible light responsive. Novel poly (methacrylic acid) grafted onto poly (vinylidene difluoride)/ poly (acrylonitrile) (PMAA-g-PVDF/ PAN) asymmetric membranes were prepared by the dry-wet phase inversion technique. The poly (methacrylic acid) (PMAA) side chains where grafted onto an activated PVDF backbone by reversible addition fragmentation chain transfer (RAFT) polymerization. The photo-catalytic membranes were generated by blending N-TiO2 with the polymer solution before casting the membranes. The membranes were characterized by FT-IR, nuclear magnetic resonance spectroscopy (NMR), scanning electron microscopy (SEM), and thermo-gravimetric analysis (TGA). FT-IR and NMR analyses confirmed successful grafting of MAA chains onto PVDF while SEM confirmed the successful preparation of membranes with asymmetric structure. The efficacy of the photo-catalytic asymmetric membranes was evaluated on the removal of herbicides from synthetic water. Bentazon was easily degraded while atrazine and paraquat were recalcitrant and proved difficult to degrade. The best results were observed with 3 % N-TiO2-PMAA-g-PVDF/ PAN asymmetric membranes on the photo-degradation of bentazon, atrazine and paraquat in water. Significant enhancement in the photo-degradation of the three herbicides was observed when photo-catalytic degradation was coupled with ozonation. Liquid chromatography-mass spectrometry (LC-MS) analysis confirmed the presence of a degradation by-product during the photo-catalytic degradation of bentazon. The photo-catalytic membranes were also evaluated on the photo-catalytic reduction of heavy metals Pb2+ and Fe3+ in water, and the best results were obtained using 1 % N-TiO2-PMAA-g-PVDF/ PAN and 1 % N-TiO2-PAN asymmetric membranes. All prepared photo-catalytic membranes where capable of completely inactivating E. coli ATCC 8739 within 120 minutes of exposure and inactivation rate increased with increasing N-TiO2 photo-catalyst loading. However, there was an indication from the results obtained that N-TiO2 supported on PMAA-g-PVDF/ PAN showed a higher inactivation rate of E. coli ATCC 8739 compared to N-TiO2-PAN and N-TiO2-PVDF membranes. The 1 % N-TiO2-PMAA-g-PVDF/ PAN membranes gave the highest pure water flux (421.83 L/m2h). This increase (PVDF = 30.50 L/m2h, PAN = 73.85 L/m2h) in pure water flux is owedb to PMAA grafting as well as addition of N-TiO2. These modifications resulted in an increased membrane surface hydrophilicity, which promoted permeation of pure water through the membrane structure. A high bovine serum albumin (BSA) rejection (76.5 %) was noted and can be attributed to steric hindrance brought about by PMAA side chains which prevented the bulky BSA molecules from attaching to the membrane surface for PMAA-g-PVDF/ PAN membranes. However, the supporting porous sub-layer of an asymmetric membrane seemed to play a very important role in the overall permeability of a membrane. PVDF membranes are highly hydrophobic hence they gave a very low pure water flux.
- Full Text:
- Date Issued: 2015
The classification performance of Bayesian Networks Classifiers: a case study of detecting Denial of Service (DoS) attacks in cloud computing environments
- Authors: Moyo, Lindani
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11405 , http://hdl.handle.net/10353/d1021327
- Description: In this research we propose a Bayesian networks approach as a promissory classification technique for detecting malicious traffic due to Denial of Service (DoS) attacks. Bayesian networks have been applied in numerous fields fraught with uncertainty and they have been proved to be successful. They have excelled tremendously in classification tasks i.e. text analysis, medical diagnoses and environmental modeling and management. The detection of DoS attacks has received tremendous attention in the field of network security. DoS attacks have proved to be detrimental and are the bane of cloud computing environments. Large business enterprises have been/or are still unwilling to outsource their businesses to the cloud due to the intrusive tendencies that the cloud platforms are prone too. To make use of Bayesian networks it is imperative to understand the ―ecosystem‖ of factors that are external to modeling the Bayesian algorithm itself. Understanding these factors have proven to result in comparable improvement in classification performance beyond the augmentation of the existing algorithms. Literature provides discussions pertaining to the factors that impact the classification capability, however it was noticed that the effects of the factors are not universal, they tend to be unique for each domain problem. This study investigates the effects of modeling parameters on the classification performance of Bayesian network classifiers in detecting DoS attacks in cloud platforms. We analyzed how structural complexity, training sample size, the choice of discretization method and lastly the score function both individually and collectively impact the performance of classifying between normal and DoS attacks on the cloud. To study the aforementioned factors, we conducted a series of experiments in detecting live DoS attacks launched against a deployed cloud and thereafter examined the classification performance in terms of accuracy of different classes of Bayesian networks. NSL-KDD dataset was used as our training set. We used ownCloud software to deploy our cloud platform. To launch DoS attacks, we used hping3 hacker friendly utility. A live packet capture was used as our test set. WEKA version 3.7.12 was used for our experiments. Our results show that the progression in model complexity improves the classification performance. This is attributed to the increase in the number of attribute correlations. Also the size of the training sample size proved to improve classification ability. Our findings noted that the choice of discretization algorithm does matter in the quest for optimal classification performance. Furthermore, our results indicate that the choice of scoring function does not affect the classification performance of Bayesian networks. Conclusions drawn from this research are prescriptive particularly for a novice machine learning researcher with valuable recommendations that ensure optimal classification performance of Bayesian networks classifiers.
- Full Text:
- Date Issued: 2015
- Authors: Moyo, Lindani
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11405 , http://hdl.handle.net/10353/d1021327
- Description: In this research we propose a Bayesian networks approach as a promissory classification technique for detecting malicious traffic due to Denial of Service (DoS) attacks. Bayesian networks have been applied in numerous fields fraught with uncertainty and they have been proved to be successful. They have excelled tremendously in classification tasks i.e. text analysis, medical diagnoses and environmental modeling and management. The detection of DoS attacks has received tremendous attention in the field of network security. DoS attacks have proved to be detrimental and are the bane of cloud computing environments. Large business enterprises have been/or are still unwilling to outsource their businesses to the cloud due to the intrusive tendencies that the cloud platforms are prone too. To make use of Bayesian networks it is imperative to understand the ―ecosystem‖ of factors that are external to modeling the Bayesian algorithm itself. Understanding these factors have proven to result in comparable improvement in classification performance beyond the augmentation of the existing algorithms. Literature provides discussions pertaining to the factors that impact the classification capability, however it was noticed that the effects of the factors are not universal, they tend to be unique for each domain problem. This study investigates the effects of modeling parameters on the classification performance of Bayesian network classifiers in detecting DoS attacks in cloud platforms. We analyzed how structural complexity, training sample size, the choice of discretization method and lastly the score function both individually and collectively impact the performance of classifying between normal and DoS attacks on the cloud. To study the aforementioned factors, we conducted a series of experiments in detecting live DoS attacks launched against a deployed cloud and thereafter examined the classification performance in terms of accuracy of different classes of Bayesian networks. NSL-KDD dataset was used as our training set. We used ownCloud software to deploy our cloud platform. To launch DoS attacks, we used hping3 hacker friendly utility. A live packet capture was used as our test set. WEKA version 3.7.12 was used for our experiments. Our results show that the progression in model complexity improves the classification performance. This is attributed to the increase in the number of attribute correlations. Also the size of the training sample size proved to improve classification ability. Our findings noted that the choice of discretization algorithm does matter in the quest for optimal classification performance. Furthermore, our results indicate that the choice of scoring function does not affect the classification performance of Bayesian networks. Conclusions drawn from this research are prescriptive particularly for a novice machine learning researcher with valuable recommendations that ensure optimal classification performance of Bayesian networks classifiers.
- Full Text:
- Date Issued: 2015
The effect of grain and soya bean-based diets on chicken production, some egg quality traits, and the potential for allergen carryover to eggs and meat
- Authors: Dokora, Adia-En-Michelle
- Date: 2015
- Subjects: Chickens -- Nutrition Chickens --Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2946 , vital:28192
- Description: This study determined the effect of maize-, whole wheat-, soya bean-based-diets on the growth performance, egg quality and dressing percentage of chickens, as well as the potential for soy and gluten allergen carryover to eggs and meat from chickens. Twenty 36-week-old Lorham White (LW) hens were divided into two groups and kept in individual cages until they reached 39-weeks of age, with water and feed supplied ad libitum. Ten LW hens were fed a maize/soya bean-based diet (T1) and the other ten birds were fed a maize/soya bean-based diet with a 15 percent whole wheat inclusion (T2) for a period of four weeks, with weekly individual hen weights and group feed consumption figures being recorded. After a two-week diet adaptation period, six eggs per treatment group were collected every second day from the LW hens’ to measure egg quality traits. Every third day, over a 29-day period, six eggs per treatment were collected and analysed for the presence of soy, gluten and gluten-derived peptides using allergen specific enzyme linked immunosorbent assays (ELISA) kits. For the broiler trial, a total of 160 Ross 308 mixed sex day old chicks were used in a completely randomized design. Two dietary treatments were assigned to eight cages (replicate) per treatment, with ten birds per cage. The Ross 308 broiler feeding programme consisted of three phases, starter (day 1 to day 10), grower (day 11 to day 20) and finisher (day 21 to day 28). At the beginning of the trial all chicks were fed T1 which contained a maize/soya bean-based diet for a period of 10 days and then eight cages with 10 birds per cage were randomly selected and fed the T2 diet, which contained a maize/soya bean-based diet with a 15 percent whole wheat inclusion, until they reached 28 days of age. Weekly live weights, feed intake, average daily gain and the average daily feed intake were recorded and calculated. At the end of the grower (day 21) and finisher phase (day 28), one broiler bird was selected per cage to have eight (8) birds per treatment and 16 birds per phase that were slaughtered and breast meat samples were analysed in duplicate for the presence of soy and gluten allergens using ELISA kits. The dressing percentage of hot carcasses was also determined at the end of the finisher phase on eight birds per treatment. For LW hens, live weight (LW) at 39 weeks of age, the average daily feed intake (ADFI) and weekly feed intakes (FI) were significantly different (P < 0.05) between treatments with birds on T2 recording higher gains. As birds age in weeks increased, significant differences (P < 0.05) in live weight values were recorded. Egg quality traits measured (shell weight, yolk weight, albumen weight, albumen height and Haugh units) were significantly different (P < 0.05) between treatments, with eggs from hens receiving T1 recording higher mean values. As hens got older, the colour of egg yolk improved, producing eggs with higher b* (yellowness) values and lower L* (lightness) and a* (redness) mean values. The Haugh unit, significantly improved (P < 0.05) as the hens got older, signifying better quality of eggs. For the broiler birds, growth traits measured indicated that there were no significant differences (P > 0.05) in live weight (LW), average daily feed intake (ADFI), weekly feed intake (FI), feed conversion ratio (FCR), cumulative feed intake (CFI) and cumulative gain (CG) between treatments. No significant differences (P > 0.05) between dressing percentage of broilers from the two treatments were observed. As birds grew, significant differences (P < 0.05) in LW, FI, AFI, FCR, and CFI, over a four-week period were recorded. Results of the allergen analyses indicated that soy and gluten allergens were not carried over from feed into eggs and meat of chickens fed a maize/soya bean-based diet and a maize/soya bean-based with a 15 percent whole wheat inclusion, respectively. In conclusion, a maize/soya bean-based diet and maize/soya bean-based diet with a 15 percent whole wheat inclusion that contained soy and gluten allergens, are feed sources that promote and stimulate 36-week-old LW hen and Ross 308 chicken growth.
- Full Text:
- Date Issued: 2015
- Authors: Dokora, Adia-En-Michelle
- Date: 2015
- Subjects: Chickens -- Nutrition Chickens --Feeding and feeds Meat -- Quality
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2946 , vital:28192
- Description: This study determined the effect of maize-, whole wheat-, soya bean-based-diets on the growth performance, egg quality and dressing percentage of chickens, as well as the potential for soy and gluten allergen carryover to eggs and meat from chickens. Twenty 36-week-old Lorham White (LW) hens were divided into two groups and kept in individual cages until they reached 39-weeks of age, with water and feed supplied ad libitum. Ten LW hens were fed a maize/soya bean-based diet (T1) and the other ten birds were fed a maize/soya bean-based diet with a 15 percent whole wheat inclusion (T2) for a period of four weeks, with weekly individual hen weights and group feed consumption figures being recorded. After a two-week diet adaptation period, six eggs per treatment group were collected every second day from the LW hens’ to measure egg quality traits. Every third day, over a 29-day period, six eggs per treatment were collected and analysed for the presence of soy, gluten and gluten-derived peptides using allergen specific enzyme linked immunosorbent assays (ELISA) kits. For the broiler trial, a total of 160 Ross 308 mixed sex day old chicks were used in a completely randomized design. Two dietary treatments were assigned to eight cages (replicate) per treatment, with ten birds per cage. The Ross 308 broiler feeding programme consisted of three phases, starter (day 1 to day 10), grower (day 11 to day 20) and finisher (day 21 to day 28). At the beginning of the trial all chicks were fed T1 which contained a maize/soya bean-based diet for a period of 10 days and then eight cages with 10 birds per cage were randomly selected and fed the T2 diet, which contained a maize/soya bean-based diet with a 15 percent whole wheat inclusion, until they reached 28 days of age. Weekly live weights, feed intake, average daily gain and the average daily feed intake were recorded and calculated. At the end of the grower (day 21) and finisher phase (day 28), one broiler bird was selected per cage to have eight (8) birds per treatment and 16 birds per phase that were slaughtered and breast meat samples were analysed in duplicate for the presence of soy and gluten allergens using ELISA kits. The dressing percentage of hot carcasses was also determined at the end of the finisher phase on eight birds per treatment. For LW hens, live weight (LW) at 39 weeks of age, the average daily feed intake (ADFI) and weekly feed intakes (FI) were significantly different (P < 0.05) between treatments with birds on T2 recording higher gains. As birds age in weeks increased, significant differences (P < 0.05) in live weight values were recorded. Egg quality traits measured (shell weight, yolk weight, albumen weight, albumen height and Haugh units) were significantly different (P < 0.05) between treatments, with eggs from hens receiving T1 recording higher mean values. As hens got older, the colour of egg yolk improved, producing eggs with higher b* (yellowness) values and lower L* (lightness) and a* (redness) mean values. The Haugh unit, significantly improved (P < 0.05) as the hens got older, signifying better quality of eggs. For the broiler birds, growth traits measured indicated that there were no significant differences (P > 0.05) in live weight (LW), average daily feed intake (ADFI), weekly feed intake (FI), feed conversion ratio (FCR), cumulative feed intake (CFI) and cumulative gain (CG) between treatments. No significant differences (P > 0.05) between dressing percentage of broilers from the two treatments were observed. As birds grew, significant differences (P < 0.05) in LW, FI, AFI, FCR, and CFI, over a four-week period were recorded. Results of the allergen analyses indicated that soy and gluten allergens were not carried over from feed into eggs and meat of chickens fed a maize/soya bean-based diet and a maize/soya bean-based with a 15 percent whole wheat inclusion, respectively. In conclusion, a maize/soya bean-based diet and maize/soya bean-based diet with a 15 percent whole wheat inclusion that contained soy and gluten allergens, are feed sources that promote and stimulate 36-week-old LW hen and Ross 308 chicken growth.
- Full Text:
- Date Issued: 2015
The effects of distance travelled, lairage duration and animal-related factors on pre-slaughter stress indicators, carcass characteristics, nanostructure and technological properties of beef
- Authors: Chulayo, Amanda Yucca
- Date: 2015
- Subjects: Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11835 , http://hdl.handle.net/10353/d1021275 , Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
- Description: The main objective of the current study was to determine the effect of distance travelled (DT), lairage duration (LDhr) and animal-related factors (animal class, breed, sex) on pre-slaughter stress indicators, carcass characteristics, nanostructure and technological properties of beef. The study was conducted in an Eastern Cape abattoir under the Buffalo City District Municipality. Six genotypes of cattle (Beefmaster, Bonsmara, Brahman, Holstein-Friesian, Non-descript and Nguni) brought for slaughter at the abattoir on different days were used in the study. Slaughter weight (SWT), warm and cold carcass weight (WCW and CCW), fatness and conformation of each animal were measured and recorded. Representative samples of blood plasma and meat quality from the Muscularis thoracis et lumborum (LTL) were collected at slaughter and 24 hours after slaughter, respectively. Heat shock proteins 70kDa (HSPA1A), glucose (GLU), cortisol (CORT), creatine kinase (CK) and lactate dehydrogenase (LDH) were determined from the blood plasma. The representative LTL muscle was used to determine ultimate pH (pHu), lightness (L*), redness (a*), yellowness (b*), meat temperature (Tm), Warner Bratzler Shear Force (WBSF) and histological structure of beef. There were significant effects of distance on pHu, Tm, a*, b*, TL%, CK and LDH. Pearson correlations were observed between distance travelled (DT), creatine kinase (CK), lactate dehydrogenase (LDH), ultimate pH (pHu), colour coordinates (L*, a* and b*) and Warner Bratzler Shear Force (WBSF). Principal component analysis (PCA) revealed that the 1st (pHu), 2nd (Tm) and 3rd (L*) principal components were the critical meat quality attributes. Positive relationships between carcass weights and beef quality characteristics for bovine cattle where the cumulative percentage of the first six principal component`s (PC`s) (SWT, WCW, CCW, DP, pHu and Tm contributed to 93.4 % of the total variance. Significant correlation coefficients between DT (r = 0.15), LDhr (r = 0.29), Ta (r = -0.52), Tm (r = 0.26), L* (r = 0.33), a* (r = 0.32) and WBSF (r = -0.49) were observed. Meat from Brahman (BR), Non-descript (ND) and Nguni (NG) cows had visible skeletal muscle fibres which were thin and long indicating improved tenderness of beef. Exposing animals to longer hours of transportation did not only reduce glucose levels but also increased the expression of HSPA1A and levels of cortisol. The CK and LDH were not related to beef quality. Therefore, CK and LDH can be used as indicators of animal welfare in slaughter cattle but cannot be used to predict the quality of meat. Bulls were the heaviest, although heifers had the highest dressing percentage than cows. Furthermore, the nanostructure of beef indicated that heifers had the best muscle fibres, sarcomere length and visible intercalated discs. The observed nanostructures of Nguni genotype are an indication of tender meat. Beef from heifers of Nguni had visible and tender meat with traces of intramuscular fat while males had shorter sarcomere length and tougher meat.
- Full Text:
- Date Issued: 2015
- Authors: Chulayo, Amanda Yucca
- Date: 2015
- Subjects: Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11835 , http://hdl.handle.net/10353/d1021275 , Slaughtering and slaughter-houses -- South Africa -- Eastern Cape , Meat -- Quality -- South Africa -- Eastern Cape , Beef -- Quality -- South Africa -- Eastern Cape , Nanostructured materials -- South Africa -- Eastern Cape , Livestock -- Handling -- South Africa -- Eastern Cape
- Description: The main objective of the current study was to determine the effect of distance travelled (DT), lairage duration (LDhr) and animal-related factors (animal class, breed, sex) on pre-slaughter stress indicators, carcass characteristics, nanostructure and technological properties of beef. The study was conducted in an Eastern Cape abattoir under the Buffalo City District Municipality. Six genotypes of cattle (Beefmaster, Bonsmara, Brahman, Holstein-Friesian, Non-descript and Nguni) brought for slaughter at the abattoir on different days were used in the study. Slaughter weight (SWT), warm and cold carcass weight (WCW and CCW), fatness and conformation of each animal were measured and recorded. Representative samples of blood plasma and meat quality from the Muscularis thoracis et lumborum (LTL) were collected at slaughter and 24 hours after slaughter, respectively. Heat shock proteins 70kDa (HSPA1A), glucose (GLU), cortisol (CORT), creatine kinase (CK) and lactate dehydrogenase (LDH) were determined from the blood plasma. The representative LTL muscle was used to determine ultimate pH (pHu), lightness (L*), redness (a*), yellowness (b*), meat temperature (Tm), Warner Bratzler Shear Force (WBSF) and histological structure of beef. There were significant effects of distance on pHu, Tm, a*, b*, TL%, CK and LDH. Pearson correlations were observed between distance travelled (DT), creatine kinase (CK), lactate dehydrogenase (LDH), ultimate pH (pHu), colour coordinates (L*, a* and b*) and Warner Bratzler Shear Force (WBSF). Principal component analysis (PCA) revealed that the 1st (pHu), 2nd (Tm) and 3rd (L*) principal components were the critical meat quality attributes. Positive relationships between carcass weights and beef quality characteristics for bovine cattle where the cumulative percentage of the first six principal component`s (PC`s) (SWT, WCW, CCW, DP, pHu and Tm contributed to 93.4 % of the total variance. Significant correlation coefficients between DT (r = 0.15), LDhr (r = 0.29), Ta (r = -0.52), Tm (r = 0.26), L* (r = 0.33), a* (r = 0.32) and WBSF (r = -0.49) were observed. Meat from Brahman (BR), Non-descript (ND) and Nguni (NG) cows had visible skeletal muscle fibres which were thin and long indicating improved tenderness of beef. Exposing animals to longer hours of transportation did not only reduce glucose levels but also increased the expression of HSPA1A and levels of cortisol. The CK and LDH were not related to beef quality. Therefore, CK and LDH can be used as indicators of animal welfare in slaughter cattle but cannot be used to predict the quality of meat. Bulls were the heaviest, although heifers had the highest dressing percentage than cows. Furthermore, the nanostructure of beef indicated that heifers had the best muscle fibres, sarcomere length and visible intercalated discs. The observed nanostructures of Nguni genotype are an indication of tender meat. Beef from heifers of Nguni had visible and tender meat with traces of intramuscular fat while males had shorter sarcomere length and tougher meat.
- Full Text:
- Date Issued: 2015
The implications of smallholder agricultural productivity growth for poverty alleviation in post-apartheid South Africa
- Authors: Dwesini, Nontembiso Eugenia
- Date: 2015
- Subjects: Agriculture -- Economic aspects -- South Africa , Agricultural assistance -- South Africa , Sustainable development -- South Africa , Agricultural productivity -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11232 , http://hdl.handle.net/10353/d1021286 , Agriculture -- Economic aspects -- South Africa , Agricultural assistance -- South Africa , Sustainable development -- South Africa , Agricultural productivity -- South Africa
- Description: The adoption of the Millennium Development Goal 1(MDG 1) of reducing the rate of poverty to half of the 1990-level by 2015 has been a challenge faced by the developing countries including South Africa. The foundations of democracy have to be continuously assessed so that the obstacles faced by South Africa as it strives towards sustainable democracy are addressed. With agricultural sector identified as having the potential to alleviate poverty compared to the mining sector, manufacturing sector and services sector, it faced the challenges that include: (i) accelerating agricultural productivity; (ii) reducing poverty and vulnerability; and (iii) narrowing rural-urban income disparities. The identification of the critical linkages in the agricultural development framework allows for effective strategic planning, effective decision making and appropriate policy formulation. Expectedly, the sector has attracted considerable fiscal policy interest and public investments. The primary aim of this research study is to assess the extent to which smallholder agricultural productivity growth alleviates poverty in South Africa. The statistical and econometric techniques namely; Johansen technique of co-integration analysis (1995), analysis of covariance and correlation, Vector Error Correction Model, are employed in this research study. The data description, data sources, expected relationship between variables and indexation of data are done. The drivers and cause-effect relationships between agriculture and poverty reduction are investigated. The employed models allowed for an exploration of plausible future growth in agricultural elasticity of poverty and the possibility of reducing poverty level in South Africa. The data is obtained from the National Department of Agriculture from 1994 -2013. The analysis of the results strongly confirms that agricultural productivity has a significant inverse relationship to the levels of poverty in South Africa. The outcome of the analysis will contribute to improved decision making on the use of public funds in agriculture.
- Full Text:
- Date Issued: 2015
- Authors: Dwesini, Nontembiso Eugenia
- Date: 2015
- Subjects: Agriculture -- Economic aspects -- South Africa , Agricultural assistance -- South Africa , Sustainable development -- South Africa , Agricultural productivity -- South Africa
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11232 , http://hdl.handle.net/10353/d1021286 , Agriculture -- Economic aspects -- South Africa , Agricultural assistance -- South Africa , Sustainable development -- South Africa , Agricultural productivity -- South Africa
- Description: The adoption of the Millennium Development Goal 1(MDG 1) of reducing the rate of poverty to half of the 1990-level by 2015 has been a challenge faced by the developing countries including South Africa. The foundations of democracy have to be continuously assessed so that the obstacles faced by South Africa as it strives towards sustainable democracy are addressed. With agricultural sector identified as having the potential to alleviate poverty compared to the mining sector, manufacturing sector and services sector, it faced the challenges that include: (i) accelerating agricultural productivity; (ii) reducing poverty and vulnerability; and (iii) narrowing rural-urban income disparities. The identification of the critical linkages in the agricultural development framework allows for effective strategic planning, effective decision making and appropriate policy formulation. Expectedly, the sector has attracted considerable fiscal policy interest and public investments. The primary aim of this research study is to assess the extent to which smallholder agricultural productivity growth alleviates poverty in South Africa. The statistical and econometric techniques namely; Johansen technique of co-integration analysis (1995), analysis of covariance and correlation, Vector Error Correction Model, are employed in this research study. The data description, data sources, expected relationship between variables and indexation of data are done. The drivers and cause-effect relationships between agriculture and poverty reduction are investigated. The employed models allowed for an exploration of plausible future growth in agricultural elasticity of poverty and the possibility of reducing poverty level in South Africa. The data is obtained from the National Department of Agriculture from 1994 -2013. The analysis of the results strongly confirms that agricultural productivity has a significant inverse relationship to the levels of poverty in South Africa. The outcome of the analysis will contribute to improved decision making on the use of public funds in agriculture.
- Full Text:
- Date Issued: 2015
The investigation of perceptions of professional nurses regarding care of mental health care users in a general hospital setting
- Manona-Nkanjeni, Nonkanyiso Yvonne
- Authors: Manona-Nkanjeni, Nonkanyiso Yvonne
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11924 , http://hdl.handle.net/10353/d1020200
- Description: This study sought to explore the perceptions of professional nurses regarding care of stabilised mental health care users in a general hospital setting. A qualitative, explanatory, descriptive and contextual design was used for the study. A non-probability, purposive sampling method was used to select 12 participants from the Cecilia Makiwane Hospital in Mdantsane. Data were collected through semi-structured interviews. The services of an independent interviewer were used to avoid any bias as interviews took place where the researcher is employed. The services of an editor were also used for language control (see Annexure H). The researcher repeatedly listened to the tapes used for data collection until completely satisfied with the interpretation of verbatim data. The research study was conducted in an ethically reflective manner and trustworthiness was ensured at all times. Four themes emerged from the analysis of the interviews: fear, stigma, myths and training. The researcher utilised the services of an independent coder who verified the identified major themes. The findings revealed that participants were fearful due to lack of knowledge, experience and psychiatric nursing skills. Participants feared because they lack knowledge about psychiatric medication and because mental health care users may have relapse. The participants also attached a stigma to mental health care users, which resulted in poor communication between participants and the stabilised mental health care user; a negative attitude towards mental health care users; and non-acceptance. Participants believed in myths about mental illness; they regarded it as contagious; and perceived mental health care users as dangerous. The participants strongly recommended that training should be provided to improve their knowledge and skills to enable them to care for stabilised mental health care users in a general hospital setting. The following should be facilitated: in-service training; adoption of a positive attitude; dispersal of myths and fear; education about referral systems; and allocation of specialist psychiatric nurses to medical wards for referral purposes with regard to complicated cases.
- Full Text:
- Date Issued: 2015
- Authors: Manona-Nkanjeni, Nonkanyiso Yvonne
- Date: 2015
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11924 , http://hdl.handle.net/10353/d1020200
- Description: This study sought to explore the perceptions of professional nurses regarding care of stabilised mental health care users in a general hospital setting. A qualitative, explanatory, descriptive and contextual design was used for the study. A non-probability, purposive sampling method was used to select 12 participants from the Cecilia Makiwane Hospital in Mdantsane. Data were collected through semi-structured interviews. The services of an independent interviewer were used to avoid any bias as interviews took place where the researcher is employed. The services of an editor were also used for language control (see Annexure H). The researcher repeatedly listened to the tapes used for data collection until completely satisfied with the interpretation of verbatim data. The research study was conducted in an ethically reflective manner and trustworthiness was ensured at all times. Four themes emerged from the analysis of the interviews: fear, stigma, myths and training. The researcher utilised the services of an independent coder who verified the identified major themes. The findings revealed that participants were fearful due to lack of knowledge, experience and psychiatric nursing skills. Participants feared because they lack knowledge about psychiatric medication and because mental health care users may have relapse. The participants also attached a stigma to mental health care users, which resulted in poor communication between participants and the stabilised mental health care user; a negative attitude towards mental health care users; and non-acceptance. Participants believed in myths about mental illness; they regarded it as contagious; and perceived mental health care users as dangerous. The participants strongly recommended that training should be provided to improve their knowledge and skills to enable them to care for stabilised mental health care users in a general hospital setting. The following should be facilitated: in-service training; adoption of a positive attitude; dispersal of myths and fear; education about referral systems; and allocation of specialist psychiatric nurses to medical wards for referral purposes with regard to complicated cases.
- Full Text:
- Date Issued: 2015
Tillage effects on the aggregate-associated organic carbon and bulk density in some South African soils with different texture
- Authors: Njeru, Sarah Kangai
- Date: 2015
- Subjects: Soil management Tillage
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2512 , vital:27881
- Description: Tillage operations disrupt the soil structure resulting in aggregates of various sizes and altered bulk density. Moreover, tillage influences soil carbon pools and many other soil physical properties. The objectives of this study were to determine, in various South African soils under different tillage systems, the following. (1) Amount of aggregate-associated soil organic carbon (SOC), (2) soil compressibility, and (3) relationship between compressibility, texture and the aggregate-associated SOC. The soil samples used in this study were collected from six different sites in Eastern Cape Province, South Africa. Soil samples were taken from conventional tillage (CT) and no-till (NT) land. To keep the soil aggregates intact sampling was done using a spade and carefully carried to the laboratory in rigid containers. For SOC determination, treatments were the two tillage systems, CT and NT, and four aggregate sizes. The experimental design was completely randomized design with a factorial layout and was replicated three times. Aggregate-associated SOC was determined using Walkley-Black method. Proctor compaction test was used determine the dry bulk density with varying moisture content and consequently the maximum bulk density (MBD) and critical water content (CWC). The aggregate-associated SOC content differed with tillage system and was significant higher (p < 0.05) in CT than NT. The amount of aggregate-associated SOC was 1.67 times higher in CT than NT plots. The MBD ranged between 1.77 g/cm3 and 10.27 g/cm3 and the CWC ranged from 9.1 percent to 10.3 percent. The higher amounts of SOC in CT were attributed to the annual crop residue returns while the lower amounts of SOC in the NT fields were due to grazing. Therefore, tillage influenced the amount of aggregate-associated organic carbon irrespective of the resulting size of the aggregate. The positive relationship between tillage and aggregate-associated SOC challenges the conversion of land to no-till for carbon sequestration. The overall gradient for correlation between the MBD and CWC was negative with r2 = 0.23 and a p value of 0.0076. The compressibility curves indicated higher values under CT if the texture class was silt clay.
- Full Text:
- Date Issued: 2015
- Authors: Njeru, Sarah Kangai
- Date: 2015
- Subjects: Soil management Tillage
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2512 , vital:27881
- Description: Tillage operations disrupt the soil structure resulting in aggregates of various sizes and altered bulk density. Moreover, tillage influences soil carbon pools and many other soil physical properties. The objectives of this study were to determine, in various South African soils under different tillage systems, the following. (1) Amount of aggregate-associated soil organic carbon (SOC), (2) soil compressibility, and (3) relationship between compressibility, texture and the aggregate-associated SOC. The soil samples used in this study were collected from six different sites in Eastern Cape Province, South Africa. Soil samples were taken from conventional tillage (CT) and no-till (NT) land. To keep the soil aggregates intact sampling was done using a spade and carefully carried to the laboratory in rigid containers. For SOC determination, treatments were the two tillage systems, CT and NT, and four aggregate sizes. The experimental design was completely randomized design with a factorial layout and was replicated three times. Aggregate-associated SOC was determined using Walkley-Black method. Proctor compaction test was used determine the dry bulk density with varying moisture content and consequently the maximum bulk density (MBD) and critical water content (CWC). The aggregate-associated SOC content differed with tillage system and was significant higher (p < 0.05) in CT than NT. The amount of aggregate-associated SOC was 1.67 times higher in CT than NT plots. The MBD ranged between 1.77 g/cm3 and 10.27 g/cm3 and the CWC ranged from 9.1 percent to 10.3 percent. The higher amounts of SOC in CT were attributed to the annual crop residue returns while the lower amounts of SOC in the NT fields were due to grazing. Therefore, tillage influenced the amount of aggregate-associated organic carbon irrespective of the resulting size of the aggregate. The positive relationship between tillage and aggregate-associated SOC challenges the conversion of land to no-till for carbon sequestration. The overall gradient for correlation between the MBD and CWC was negative with r2 = 0.23 and a p value of 0.0076. The compressibility curves indicated higher values under CT if the texture class was silt clay.
- Full Text:
- Date Issued: 2015
A comparative evolutionary approach to gum-feeding in Galago Moholi and Microcebus Griseorufus
- Authors: Andrews, Curswan Allan
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11795 , http://hdl.handle.net/10353/d1019831
- Description: Gums are soluble plant exudates rich in complex carbohydrates. In primates, the consumption of gum (gummivory) has been described as a primitive, fall-back diet exhibited when other food sources become scarce, particularly during dry periods. In apparent support for this interpretation, gummivory is often observed in nocturnal strepsirhines (tooth-combed primates) believed to have retained many primitive features. The complex carbohydrates in gums, however, are also known to be difficult to digest, and require particular alimentary adaptations. The hypothesis of a primitive diet predicts that gummivorous strepsirhines should use homologous digestive strategies, while the presence of different digestive adaptations in different lineages would suggest convergent evolution. I compared the digestive adaptations to gummivory in two small strepsirhine taxa, African lesser bushbabies (Galago moholi) and Malagasy reddish-grey mouse lemurs (Microcebus griseorufus). Both taxa digest gum primarily by fermentation, and have enlarged caeca for this process, but only G. moholi has an ansa coli in which digestion can be continued. In captive feeding experiments, the faeces of wild-caught G. moholi and M. griseorufus showed no significant difference in their digestive efficiency of gum compared with a control food (banana), and the banana and gum samples showed no significant difference in nutrient concentration and overall composition. To gain a broader understanding of the origins of gummivory in strepsirhines, I used a phylogenetic method to reconstruct their dietary evolution. My results indicate that gummivory evolved convergently in several primate lineages, apparently in response to environmental hypervariability. I conducted biochemical analyses of the secondary compounds found in gums that are regularly consumed, and preliminary results show that Commiphora spp. have a number of compounds, while Acacia spp. show no such traces. The absence of secondary compounds from M. griseorufus faeces suggests that the animals have physiological means for either converting them into digestible products or detoxifying and excreting them in their urine. Finally, I compared the distribution patterns of G. moholi and M. griseorufus with climatic parameters; both study taxa inhabit regions in which the dry season is characterised by little to no rainfall, a drought that may persist for months. Similar climatic regions are occupied by other gum-feeders, including the marsupial gliders (Petauridae) of Australia.
- Full Text:
- Date Issued: 2014
- Authors: Andrews, Curswan Allan
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Zoology)
- Identifier: vital:11795 , http://hdl.handle.net/10353/d1019831
- Description: Gums are soluble plant exudates rich in complex carbohydrates. In primates, the consumption of gum (gummivory) has been described as a primitive, fall-back diet exhibited when other food sources become scarce, particularly during dry periods. In apparent support for this interpretation, gummivory is often observed in nocturnal strepsirhines (tooth-combed primates) believed to have retained many primitive features. The complex carbohydrates in gums, however, are also known to be difficult to digest, and require particular alimentary adaptations. The hypothesis of a primitive diet predicts that gummivorous strepsirhines should use homologous digestive strategies, while the presence of different digestive adaptations in different lineages would suggest convergent evolution. I compared the digestive adaptations to gummivory in two small strepsirhine taxa, African lesser bushbabies (Galago moholi) and Malagasy reddish-grey mouse lemurs (Microcebus griseorufus). Both taxa digest gum primarily by fermentation, and have enlarged caeca for this process, but only G. moholi has an ansa coli in which digestion can be continued. In captive feeding experiments, the faeces of wild-caught G. moholi and M. griseorufus showed no significant difference in their digestive efficiency of gum compared with a control food (banana), and the banana and gum samples showed no significant difference in nutrient concentration and overall composition. To gain a broader understanding of the origins of gummivory in strepsirhines, I used a phylogenetic method to reconstruct their dietary evolution. My results indicate that gummivory evolved convergently in several primate lineages, apparently in response to environmental hypervariability. I conducted biochemical analyses of the secondary compounds found in gums that are regularly consumed, and preliminary results show that Commiphora spp. have a number of compounds, while Acacia spp. show no such traces. The absence of secondary compounds from M. griseorufus faeces suggests that the animals have physiological means for either converting them into digestible products or detoxifying and excreting them in their urine. Finally, I compared the distribution patterns of G. moholi and M. griseorufus with climatic parameters; both study taxa inhabit regions in which the dry season is characterised by little to no rainfall, a drought that may persist for months. Similar climatic regions are occupied by other gum-feeders, including the marsupial gliders (Petauridae) of Australia.
- Full Text:
- Date Issued: 2014
A decentralized multi-agent based network management system for ICT4D networks
- Authors: Matebese, Sithembiso
- Date: 2014
- Subjects: Microsoft� Word 2010
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11398 , http://hdl.handle.net/10353/d1019853
- Description: Network management is fundamental for assuring high quality services required by each user for the effective utilization of network resources. In this research, we propose the use of a decentralized, flexible and scalable Multi-Agent based system to monitor and manage rural broadband networks adaptively and efficiently. This mechanism is not novel as it has been used for high-speed, large-scale and distributed networks. This research investigates how software agents could collaborate in the process of managing rural broadband networks and developing an autonomous decentralized network management mechanism. In rural networks, network management is a challenging task because of lack of a reliable power supply, greater geographical distances, topographical barriers, and lack of technical support as well as computer repair facilities. This renders the network monitoring function complex and difficult. Since software agents are goal-driven, this research aims at developing a distributed management system that efficiently diagnoses errors on a given network and autonomously invokes effective changes to the network based on the goals defined on system agents. To make this possible, the Siyakhula Living Lab network was used as the research case study and existing network management system was reviewed and used as the basis for the proposed network management system. The proposed network management system uses JADE framework, Hyperic-Sigar API, Java networking programming and JESS scripting language to implement reasoning software agents. JADE and Java were used to develop the system agents with FIPA specifications. Hyperic-Sigar was used to collect the device information, Jpcap was used for collecting device network information and JESS for developing a rule engine for agents to reason about the device and network state. Even though the system is developed with Siyakhula Living Lab considerations, technically it can be used in any small-medium network because it is adaptable and scalable to various network infrastructure requirements. The proposed system consists of two types of agents, the MasterAgent and the NodeAgent. The MasterAgent resides on the device that has the agent platform and NodeAgent resides on devices connected to the network. The MasterAgent provides the network administrator with graphical and web user interfaces so that they can view network analysis and statistics. The agent platform provides agents with the executing environment and every agent, when started, is added to this platform. This system is platform independent as it has been tested on Linux, Mac and Windows platforms. The implemented system has been found to provide a suitable network management function to rural broadband networks that is: scalable in that more node agents can be added to the system to accommodate more devices in the network; autonomous in the ability to reason and execute actions based on the defined rules; fault-tolerant through being designed as a decentralized platform thereby reducing the Single Point of Failure (SPOF) in the system.
- Full Text:
- Date Issued: 2014
- Authors: Matebese, Sithembiso
- Date: 2014
- Subjects: Microsoft� Word 2010
- Language: English
- Type: Thesis , Masters , MSc (Computer Science)
- Identifier: vital:11398 , http://hdl.handle.net/10353/d1019853
- Description: Network management is fundamental for assuring high quality services required by each user for the effective utilization of network resources. In this research, we propose the use of a decentralized, flexible and scalable Multi-Agent based system to monitor and manage rural broadband networks adaptively and efficiently. This mechanism is not novel as it has been used for high-speed, large-scale and distributed networks. This research investigates how software agents could collaborate in the process of managing rural broadband networks and developing an autonomous decentralized network management mechanism. In rural networks, network management is a challenging task because of lack of a reliable power supply, greater geographical distances, topographical barriers, and lack of technical support as well as computer repair facilities. This renders the network monitoring function complex and difficult. Since software agents are goal-driven, this research aims at developing a distributed management system that efficiently diagnoses errors on a given network and autonomously invokes effective changes to the network based on the goals defined on system agents. To make this possible, the Siyakhula Living Lab network was used as the research case study and existing network management system was reviewed and used as the basis for the proposed network management system. The proposed network management system uses JADE framework, Hyperic-Sigar API, Java networking programming and JESS scripting language to implement reasoning software agents. JADE and Java were used to develop the system agents with FIPA specifications. Hyperic-Sigar was used to collect the device information, Jpcap was used for collecting device network information and JESS for developing a rule engine for agents to reason about the device and network state. Even though the system is developed with Siyakhula Living Lab considerations, technically it can be used in any small-medium network because it is adaptable and scalable to various network infrastructure requirements. The proposed system consists of two types of agents, the MasterAgent and the NodeAgent. The MasterAgent resides on the device that has the agent platform and NodeAgent resides on devices connected to the network. The MasterAgent provides the network administrator with graphical and web user interfaces so that they can view network analysis and statistics. The agent platform provides agents with the executing environment and every agent, when started, is added to this platform. This system is platform independent as it has been tested on Linux, Mac and Windows platforms. The implemented system has been found to provide a suitable network management function to rural broadband networks that is: scalable in that more node agents can be added to the system to accommodate more devices in the network; autonomous in the ability to reason and execute actions based on the defined rules; fault-tolerant through being designed as a decentralized platform thereby reducing the Single Point of Failure (SPOF) in the system.
- Full Text:
- Date Issued: 2014
A socio-economic impact assessment (SEIA) of the Idutywa agripark project on project beneficiaries in Mbashe local municipality of the Eastern Cape Province
- Authors: Magida, Phiwokuhle Thulani
- Date: 2014
- Subjects: Rural poor -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11211 , http://hdl.handle.net/10353/d1016195 , Rural poor -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa , Sustainable development -- South Africa -- Eastern Cape
- Description: Poverty, inequality and unemployment have always been challenging first in South Africa with special reference to rural South Africa. These persistent challenges with severe impacts on black population are believed to be the results of the previous governance in South Africa. Policies have been formulated, reformulated and others implemented in a form of development projects which have achieved little success in pursuit of combating these challenges. However, in the process of achieving rural development through developmental projects, a fundamental stage in the life cycle of these projects is often omitted or given little attention. This stage is the monitoring and evaluation stage which is critical to ascertain potential impacts (both positive and negative) especially if the project is to be replicated and achieve its objectives as postulated in the millennium development goals. This thesis attempted to carry out a Socio-Economic Impact Assessment (SEIA) of the Agripark project implemented at Dutywa on the livelihoods of communities directly affected by this project. The Agripark project is a project that comprises three linked components, a seedling nursery, an agro-processing facility and a sizeable feeder plot and has been implemented to benefit four villages. This project has been implemented as the second Agripark project by the University of Fort Hare in partnership with the province’s Department of Agriculture. To track change after the implementation of the project, data were collected from the same respondents that were interviewed for the baseline study, therefore, the same sample size that was used in the baseline study was also used for this study. As a tool for data collection, a questionnaire was developed to elicit the required information and was interviewer administered during data collection. The results of the study revealed that Agripark project has impact on both social and economic wellbeing of the households. The processing unit of the project was not yet functioning therefore the project was not fully effective thus the impact was not as intended by the project when the study was carried out. Skills transferred were only on production but only a small number of people could receive them. These households largely relied on external sources of income mainly on social grants and their contribution to total household income had increased to 88% in 2011 compared to 80% in 2008. As much as the increase in incomes cannot be entirely be because of the project but Agripark had a positive impact on household incomes through wages of those employed there and through increased profitability of hawking vegetables. The proportion of household earning incomes less than the Poverty line fell from 85% in 2008 to approximately 79% in 2011. The household complemented their staples with a variety of vegetables and the main source of these vegetables was Agripark even though own production was declining. Even though food was still the main item of these households expenditure, the proportion of income spent on food fell from 64% in 2008 to 48% in 2011. There were no environmental impacts found. From the descriptive analysis, the project had impact on the livelihoods of these households because it brought change on the household expenditure as a result of the income earned by those who are working in the Agripark. There was an improvement on risk of food insecurity through cheaper vegetable that both physically and financially attainable. However, as much as the project had positive impact, there were also concerns raised by the respondents that the employment was only biased to certain individuals which cased stress to some households. Furthermore, the empirical analysis of the selected variables showed that participation in Agripark had an impact on economic wellbeing of the beneficiaries. Thus, funding must be made available to the project so that it can upgrade their electricity and have the processing plant running as it may be the major source of employment, skills development and achievement of its objectives.
- Full Text:
- Date Issued: 2014
- Authors: Magida, Phiwokuhle Thulani
- Date: 2014
- Subjects: Rural poor -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa , Sustainable development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11211 , http://hdl.handle.net/10353/d1016195 , Rural poor -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa , Sustainable development -- South Africa -- Eastern Cape
- Description: Poverty, inequality and unemployment have always been challenging first in South Africa with special reference to rural South Africa. These persistent challenges with severe impacts on black population are believed to be the results of the previous governance in South Africa. Policies have been formulated, reformulated and others implemented in a form of development projects which have achieved little success in pursuit of combating these challenges. However, in the process of achieving rural development through developmental projects, a fundamental stage in the life cycle of these projects is often omitted or given little attention. This stage is the monitoring and evaluation stage which is critical to ascertain potential impacts (both positive and negative) especially if the project is to be replicated and achieve its objectives as postulated in the millennium development goals. This thesis attempted to carry out a Socio-Economic Impact Assessment (SEIA) of the Agripark project implemented at Dutywa on the livelihoods of communities directly affected by this project. The Agripark project is a project that comprises three linked components, a seedling nursery, an agro-processing facility and a sizeable feeder plot and has been implemented to benefit four villages. This project has been implemented as the second Agripark project by the University of Fort Hare in partnership with the province’s Department of Agriculture. To track change after the implementation of the project, data were collected from the same respondents that were interviewed for the baseline study, therefore, the same sample size that was used in the baseline study was also used for this study. As a tool for data collection, a questionnaire was developed to elicit the required information and was interviewer administered during data collection. The results of the study revealed that Agripark project has impact on both social and economic wellbeing of the households. The processing unit of the project was not yet functioning therefore the project was not fully effective thus the impact was not as intended by the project when the study was carried out. Skills transferred were only on production but only a small number of people could receive them. These households largely relied on external sources of income mainly on social grants and their contribution to total household income had increased to 88% in 2011 compared to 80% in 2008. As much as the increase in incomes cannot be entirely be because of the project but Agripark had a positive impact on household incomes through wages of those employed there and through increased profitability of hawking vegetables. The proportion of household earning incomes less than the Poverty line fell from 85% in 2008 to approximately 79% in 2011. The household complemented their staples with a variety of vegetables and the main source of these vegetables was Agripark even though own production was declining. Even though food was still the main item of these households expenditure, the proportion of income spent on food fell from 64% in 2008 to 48% in 2011. There were no environmental impacts found. From the descriptive analysis, the project had impact on the livelihoods of these households because it brought change on the household expenditure as a result of the income earned by those who are working in the Agripark. There was an improvement on risk of food insecurity through cheaper vegetable that both physically and financially attainable. However, as much as the project had positive impact, there were also concerns raised by the respondents that the employment was only biased to certain individuals which cased stress to some households. Furthermore, the empirical analysis of the selected variables showed that participation in Agripark had an impact on economic wellbeing of the beneficiaries. Thus, funding must be made available to the project so that it can upgrade their electricity and have the processing plant running as it may be the major source of employment, skills development and achievement of its objectives.
- Full Text:
- Date Issued: 2014
Aggregate stability, crust formation, steady state infiltration and mode of seedling emergence in soils with various texture and mineralogy
- Authors: Nciizah, Adornis Dakarai
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Crop Science)
- Identifier: vital:11871 , http://hdl.handle.net/10353/d1015539
- Description: The general objective of this study was to quantify the interactive effects of soil texture and mineralogy on soil crusting, infiltration and erosion and the subsequent effects on maize seedling emergence and early development using soils collected from 14 ecotopes in the Eastern Cape Province. The specific objectives were to determine; i) particulate organic matter, soil texture and mineralogy relations, ii) aggregate stability and breakdown mechanisms as affected by soil texture and organic matter, iii) crust formation and steady state infiltration, iv) rainfall pattern effects on crusting, infiltration and erodibility and v) rainfall intensity effects on crusting and mode of seedling emergence. Particulate organic matter (POM) was fractionated into litter POM, coarse POM and fine POM. Both total soil organic matter (SOM) and the POM in each fraction were determined using the weight loss on ignition procedure. Most ecotopes were either sandy loam or sandy clay loam and primary minerals especially quartz dominated the soil mineralogy. The clay content was significantly related to the total SOM (r = 0.78), hematite (r = 0.83) and quartz (r = -0.74). Aggregate stability was determined following methods described by Le Bissonnais (1996) i.e. fast wetting (FW), slow wetting (SW) and wet stirring (WSt). Aggregate breakdown followed the order; slaking < mechanical breakdown < micro-cracking for most ecotopes except Lujiko Leeufontein and Amatola Jozini where SW and WSt resulted in the least MWD respectively. Aggregate stability was significantly correlated to POM only for FW and SW and only positive but not significant for WSt. To study crust formation, aggregate sizes <2, 2 to 3, 3 to 5 mm were exposed to 60 mm hr-1 simulated rainfall. Sieving structural crusts, ~0.2 to ~0.8 mm thick with a surface layer of loose grains overlying a thin plasmic layer, formed in all ecotopes. Crusts with strengths between 0.25 and 3.42 10-4 kg m-2 developed on the <2 mm compared to <2.23 10-4 kg m-2 in the >2 mm aggregates. The reverse occurred in Alice Jozini, which had relatively low clay content of 120 g kg-1. Two significantly different groups of the SSIR were observed. The SSIR was between 1.24 and 3.60 mm hr-1 in the group of ecotopes dominated by primary minerals and relatively lower clay content. In the second group, consisting one ecotope dominated by kaolinite and relatively higher clay content, the SSIR was 15.23 mm hr-1. Rainfall pattern i.e. rainfall applied either as an eight minute single rainstorm (SR) or four-two minute intermittent rainstorms (IR) separated by a 48 h drying period significantly (p < 0.05) affected crust strength, SSIR and erosion. The IR resulted in higher crust strength and SSIR than SR. The effect of rainfall pattern on SSIR was mostly influenced by the primary minerals namely, quartz. Three maize seeds of equal size were planted in plastic pots, pre-wetted by capillary action and then subjected to simulated rainfall at three intensities for 5 min. Rainfall intensity (30, 45 and 60 mm h-1) significantly (P < 0.05) affected crust strength and mean emergence day (MED) but not emergence percentage (EMP) and shoot length (P > 0.05). The 60 mm h-1 rainfall intensity resulted in the highest crust strength and MED.
- Full Text:
- Date Issued: 2014
- Authors: Nciizah, Adornis Dakarai
- Date: 2014
- Language: English
- Type: Thesis , Doctoral , PhD (Crop Science)
- Identifier: vital:11871 , http://hdl.handle.net/10353/d1015539
- Description: The general objective of this study was to quantify the interactive effects of soil texture and mineralogy on soil crusting, infiltration and erosion and the subsequent effects on maize seedling emergence and early development using soils collected from 14 ecotopes in the Eastern Cape Province. The specific objectives were to determine; i) particulate organic matter, soil texture and mineralogy relations, ii) aggregate stability and breakdown mechanisms as affected by soil texture and organic matter, iii) crust formation and steady state infiltration, iv) rainfall pattern effects on crusting, infiltration and erodibility and v) rainfall intensity effects on crusting and mode of seedling emergence. Particulate organic matter (POM) was fractionated into litter POM, coarse POM and fine POM. Both total soil organic matter (SOM) and the POM in each fraction were determined using the weight loss on ignition procedure. Most ecotopes were either sandy loam or sandy clay loam and primary minerals especially quartz dominated the soil mineralogy. The clay content was significantly related to the total SOM (r = 0.78), hematite (r = 0.83) and quartz (r = -0.74). Aggregate stability was determined following methods described by Le Bissonnais (1996) i.e. fast wetting (FW), slow wetting (SW) and wet stirring (WSt). Aggregate breakdown followed the order; slaking < mechanical breakdown < micro-cracking for most ecotopes except Lujiko Leeufontein and Amatola Jozini where SW and WSt resulted in the least MWD respectively. Aggregate stability was significantly correlated to POM only for FW and SW and only positive but not significant for WSt. To study crust formation, aggregate sizes <2, 2 to 3, 3 to 5 mm were exposed to 60 mm hr-1 simulated rainfall. Sieving structural crusts, ~0.2 to ~0.8 mm thick with a surface layer of loose grains overlying a thin plasmic layer, formed in all ecotopes. Crusts with strengths between 0.25 and 3.42 10-4 kg m-2 developed on the <2 mm compared to <2.23 10-4 kg m-2 in the >2 mm aggregates. The reverse occurred in Alice Jozini, which had relatively low clay content of 120 g kg-1. Two significantly different groups of the SSIR were observed. The SSIR was between 1.24 and 3.60 mm hr-1 in the group of ecotopes dominated by primary minerals and relatively lower clay content. In the second group, consisting one ecotope dominated by kaolinite and relatively higher clay content, the SSIR was 15.23 mm hr-1. Rainfall pattern i.e. rainfall applied either as an eight minute single rainstorm (SR) or four-two minute intermittent rainstorms (IR) separated by a 48 h drying period significantly (p < 0.05) affected crust strength, SSIR and erosion. The IR resulted in higher crust strength and SSIR than SR. The effect of rainfall pattern on SSIR was mostly influenced by the primary minerals namely, quartz. Three maize seeds of equal size were planted in plastic pots, pre-wetted by capillary action and then subjected to simulated rainfall at three intensities for 5 min. Rainfall intensity (30, 45 and 60 mm h-1) significantly (P < 0.05) affected crust strength and mean emergence day (MED) but not emergence percentage (EMP) and shoot length (P > 0.05). The 60 mm h-1 rainfall intensity resulted in the highest crust strength and MED.
- Full Text:
- Date Issued: 2014
Alternative methods used by small-holder farmers to control ticks and bovine dermatophilosis and the impact of a changing interface of Amblyomma ticks on dermatophilosis in Zimbabwe
- Authors: Ndhkovu, Daud Nyosi
- Date: 2014
- Subjects: Ticks -- Control -- Africa, Southern , Dermatophilosis
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11830 , http://hdl.handle.net/10353/d1019764 , Ticks -- Control -- Africa, Southern , Dermatophilosis
- Description: This study was carried out to document the ethno-veterinary plants and non-plant remedies that farmers used to control dermatophilosis and ticks, and validate these in vitro and in vivo, as well as determine how the interface of Amblyomma variegatum and A. hebraeum affected the epidemiology of bovine dermatophilosis at selected small-holder areas in North-West Zimbabwe. A structured questionnaire survey was used to collect information on the control methods used by farmers for the control of bovine dermatophilosis and ticks. A total of 39 plants were used by farmers for various diseases, eleven of these plants were used for the control of dermatophilosis while three were for tick control. Across the study sites, dermatophilosis was controlled using eleven plants. Among these plants; six plants; Cissus quadrangularis, Catunaregan spinosa, Pterocarpus angolensis Carica papaya, Manihot esculenta and Blumea decurrens which were frequently used were selected for further studies. In vitro and in vivo studies were conducted to validate the efficacy of these plants. The minimum inhibitory concentration and bactericidal concentration assays were used for the in vitro validation of C. quadrangularis, C. spinosa and P. angolensis. Dermatophilus congolensis was more sensitive to P. angolensis average MIC = 0.63 mg/ml than to C. quadrangularis average MIC = iii 1.25 mg/ml and C. spinosa average MIC = 2.08 mg/ml. Cissus quadrangularis was selected for in vivo studies as this plant was the one most frequently used by farmers. Its therapeutic efficacy was compared to conventional antibiotics that farmers used to treat dermatophilosis infection. In the in vivo trials C. quadrangularis did not lead to appreciable reduction in clinical disease compared to the conventional drugs. The larval packet assay was the in vitro assay used to validate the efficacy of Carica papaya, Manihot esculenta and Blumea decurrens against larvae of A. hebraeum and Rhipicephalus appendiculatus. Manihot esculenta at 20 % w/v exhibited the highest larvicidal activity against R. appendiculatus. In the in vivo study, efficacy of the plants were investigated on naturally tick-infested cattle. Mannihot esculenta exhibited the largest tick load reduction compared to the other two plants but its performance was lower than that of conventional acaricides. The effect of A. variegatum and A. hebraeum on bovine dermatophilosis was investigated by evaluating how the presence or absence of these ticks and other herd level risk factors predicted clinical dermatophilosis and its prevalence at herd level. A structured questionnaire survey was carried out to collect data on potential risk factors. At the same time, cattle were physically examined for the presence of bovine dermatophilosis, according to a pre-defined case definition, and presence or absence of Amblyomma ticks was also recorded. The multivariable binary logistic model was developed with disease status as outcome, tick presence and infestion and herd level risk factors as predictors. Of the herds examined clinical bovine dermatophilosis was detected in 45% (84/185; 95% CI: 38.2, 52.6%) of them. Herds infested with Amblyomma variegatum were associated with higher odds (OR= 6.8; iv 95% CI: 1.71, 27.10) of clinical dermatophilosis while the association was not significant (P > 0.05) in A. hebraeum infested herds. It was concluded that management practices aimed at movement and tick control would help reduce the prevalence of clinical dermatophilosis in herds.
- Full Text:
- Date Issued: 2014
- Authors: Ndhkovu, Daud Nyosi
- Date: 2014
- Subjects: Ticks -- Control -- Africa, Southern , Dermatophilosis
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11830 , http://hdl.handle.net/10353/d1019764 , Ticks -- Control -- Africa, Southern , Dermatophilosis
- Description: This study was carried out to document the ethno-veterinary plants and non-plant remedies that farmers used to control dermatophilosis and ticks, and validate these in vitro and in vivo, as well as determine how the interface of Amblyomma variegatum and A. hebraeum affected the epidemiology of bovine dermatophilosis at selected small-holder areas in North-West Zimbabwe. A structured questionnaire survey was used to collect information on the control methods used by farmers for the control of bovine dermatophilosis and ticks. A total of 39 plants were used by farmers for various diseases, eleven of these plants were used for the control of dermatophilosis while three were for tick control. Across the study sites, dermatophilosis was controlled using eleven plants. Among these plants; six plants; Cissus quadrangularis, Catunaregan spinosa, Pterocarpus angolensis Carica papaya, Manihot esculenta and Blumea decurrens which were frequently used were selected for further studies. In vitro and in vivo studies were conducted to validate the efficacy of these plants. The minimum inhibitory concentration and bactericidal concentration assays were used for the in vitro validation of C. quadrangularis, C. spinosa and P. angolensis. Dermatophilus congolensis was more sensitive to P. angolensis average MIC = 0.63 mg/ml than to C. quadrangularis average MIC = iii 1.25 mg/ml and C. spinosa average MIC = 2.08 mg/ml. Cissus quadrangularis was selected for in vivo studies as this plant was the one most frequently used by farmers. Its therapeutic efficacy was compared to conventional antibiotics that farmers used to treat dermatophilosis infection. In the in vivo trials C. quadrangularis did not lead to appreciable reduction in clinical disease compared to the conventional drugs. The larval packet assay was the in vitro assay used to validate the efficacy of Carica papaya, Manihot esculenta and Blumea decurrens against larvae of A. hebraeum and Rhipicephalus appendiculatus. Manihot esculenta at 20 % w/v exhibited the highest larvicidal activity against R. appendiculatus. In the in vivo study, efficacy of the plants were investigated on naturally tick-infested cattle. Mannihot esculenta exhibited the largest tick load reduction compared to the other two plants but its performance was lower than that of conventional acaricides. The effect of A. variegatum and A. hebraeum on bovine dermatophilosis was investigated by evaluating how the presence or absence of these ticks and other herd level risk factors predicted clinical dermatophilosis and its prevalence at herd level. A structured questionnaire survey was carried out to collect data on potential risk factors. At the same time, cattle were physically examined for the presence of bovine dermatophilosis, according to a pre-defined case definition, and presence or absence of Amblyomma ticks was also recorded. The multivariable binary logistic model was developed with disease status as outcome, tick presence and infestion and herd level risk factors as predictors. Of the herds examined clinical bovine dermatophilosis was detected in 45% (84/185; 95% CI: 38.2, 52.6%) of them. Herds infested with Amblyomma variegatum were associated with higher odds (OR= 6.8; iv 95% CI: 1.71, 27.10) of clinical dermatophilosis while the association was not significant (P > 0.05) in A. hebraeum infested herds. It was concluded that management practices aimed at movement and tick control would help reduce the prevalence of clinical dermatophilosis in herds.
- Full Text:
- Date Issued: 2014
Alternative remedies used by resource-limited farmers in the treatment and manipulation of the reproductive system of non-descript goats in the Eastern Cape Province, South Africa
- Authors: Rwodzi, Maxwell
- Date: 2014
- Subjects: Goats -- South Africa -- Eastern Cape , Traditional veterinary medicine -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11831 , http://hdl.handle.net/10353/d1019767 , Goats -- South Africa -- Eastern Cape , Traditional veterinary medicine -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: This study was carried out to determine alternative approaches used by resource-limited farmers to enhance fertility and in the treatment of reproduction ailments of goats in Mount Frere area, Eastern Cape Province of South Africa. Furthermore, information on farmer perceptions pertaining to these practices was also gathered. A questionnaire survey was conducted to determine materials used by resource-limited farmers to enhance fertility and treat reproductive ailments. The survey revealed 10 plant species that were commonly used for reproductive health in goats. Elephantorrhizza elephantina (37.1%) and Rhoicissus tomentosa (25.7%) were the most frequently cited plant species. Elephantorrhiza elephantina and R. tomentosa recorded the highest Fidelity Level (FL) values of 92.86% and 75% respectively, for their use in the treatment of reproductive ailments and these were the plants on which further studies were conducted. The study also revealed that farmers had different perceptions on the effectiveness of the traditional medicines. An in-vivo assessment was done to determine efficacy of E. elephantina and R. tomentosa using serum estradiol and progesterone profiles. The highest (P<0.05) serum estradiol and progesterone concentration was observed in animals administered with aqueous extracts of E. elephantina and R. tomentosa mixture while the least (P<0.05) concentrations were observed in the negative control group. Does administered with a mixture of aqueous E. elephantina and R. tomentosa extract had the highest (P<0.05) body weight (65 kg) as well as body condition scores, while the negative control which were administered with distilled water had the least body weights (54 kg) and body condition scores. Does that were administered with a mixture of E.elephantina and R. tomentosa were all pregnant with twins (100%), confirmed by a doppler ultrasound scan.
- Full Text:
- Date Issued: 2014
- Authors: Rwodzi, Maxwell
- Date: 2014
- Subjects: Goats -- South Africa -- Eastern Cape , Traditional veterinary medicine -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11831 , http://hdl.handle.net/10353/d1019767 , Goats -- South Africa -- Eastern Cape , Traditional veterinary medicine -- South Africa -- Eastern Cape , Sustainable agriculture -- South Africa -- Eastern Cape
- Description: This study was carried out to determine alternative approaches used by resource-limited farmers to enhance fertility and in the treatment of reproduction ailments of goats in Mount Frere area, Eastern Cape Province of South Africa. Furthermore, information on farmer perceptions pertaining to these practices was also gathered. A questionnaire survey was conducted to determine materials used by resource-limited farmers to enhance fertility and treat reproductive ailments. The survey revealed 10 plant species that were commonly used for reproductive health in goats. Elephantorrhizza elephantina (37.1%) and Rhoicissus tomentosa (25.7%) were the most frequently cited plant species. Elephantorrhiza elephantina and R. tomentosa recorded the highest Fidelity Level (FL) values of 92.86% and 75% respectively, for their use in the treatment of reproductive ailments and these were the plants on which further studies were conducted. The study also revealed that farmers had different perceptions on the effectiveness of the traditional medicines. An in-vivo assessment was done to determine efficacy of E. elephantina and R. tomentosa using serum estradiol and progesterone profiles. The highest (P<0.05) serum estradiol and progesterone concentration was observed in animals administered with aqueous extracts of E. elephantina and R. tomentosa mixture while the least (P<0.05) concentrations were observed in the negative control group. Does administered with a mixture of aqueous E. elephantina and R. tomentosa extract had the highest (P<0.05) body weight (65 kg) as well as body condition scores, while the negative control which were administered with distilled water had the least body weights (54 kg) and body condition scores. Does that were administered with a mixture of E.elephantina and R. tomentosa were all pregnant with twins (100%), confirmed by a doppler ultrasound scan.
- Full Text:
- Date Issued: 2014
An assessment of the impact of animal traction on rural household food security: a case of Damane rural community of Cofimvaba in the Eastern Cape Province of South Africa
- Authors: Manzana, Sihle
- Date: 2014
- Subjects: Animal traction -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11208 , http://hdl.handle.net/10353/d1016162 , Animal traction -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Description: This dissertation assesses the impact of animal traction on rural household food security. Since rural communities do not have sufficient agricultural capital to purchase improved agricultural technologies for better crop production, and often lack knowledge and skills to apply improved technologies low-cost alternatives must be sought. For these reasons, animal traction has been seen by researchers as an affordable, easy-to-use, sustainable and appropriate operation for crops production in rural areas. Animal traction has been long used and it continues to be used in rural areas to improve food insecurities. But the system confronts a number of constraints that impede the development of its full potential and these should be addressed in order to reap the full benefits of agricultural restructuring in the rural areas. A study was carried out in Damane rural village under Ntsika Yethu Municipality in the Eastern Cape where animal traction is very popular. A total of 80 small-scale farmers were interviewed by means of structured questionnaires to collect data from adopters and non-adopters of animal traction. A wide range of analytical techniques were employed to assess the impact of animal traction on household food production. Descriptive statistics was employed for analyses of demographic, agricultural production process of the surveyed households and challenges encountered by households. Multiple Linear Regression was applied to determine the factors affecting animal traction use and the extent to which they contribute to gross farm production. The results of the multiple linear regressions showed that animal traction played a significant role in the total output of all the crops produced last season. The results of the t- tests showed that animal traction was the most effective technology compared to the simple hand-tools such as fork, fork spade and hoes. The binary logistic regression was employed to test the probability that resource poor households would adopt animal traction technology. It is therefore recommended that government should support animal traction users by providing all the necessary resources for development of animal in rural South Africa.
- Full Text:
- Date Issued: 2014
- Authors: Manzana, Sihle
- Date: 2014
- Subjects: Animal traction -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11208 , http://hdl.handle.net/10353/d1016162 , Animal traction -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Food security -- South Africa -- Eastern Cape
- Description: This dissertation assesses the impact of animal traction on rural household food security. Since rural communities do not have sufficient agricultural capital to purchase improved agricultural technologies for better crop production, and often lack knowledge and skills to apply improved technologies low-cost alternatives must be sought. For these reasons, animal traction has been seen by researchers as an affordable, easy-to-use, sustainable and appropriate operation for crops production in rural areas. Animal traction has been long used and it continues to be used in rural areas to improve food insecurities. But the system confronts a number of constraints that impede the development of its full potential and these should be addressed in order to reap the full benefits of agricultural restructuring in the rural areas. A study was carried out in Damane rural village under Ntsika Yethu Municipality in the Eastern Cape where animal traction is very popular. A total of 80 small-scale farmers were interviewed by means of structured questionnaires to collect data from adopters and non-adopters of animal traction. A wide range of analytical techniques were employed to assess the impact of animal traction on household food production. Descriptive statistics was employed for analyses of demographic, agricultural production process of the surveyed households and challenges encountered by households. Multiple Linear Regression was applied to determine the factors affecting animal traction use and the extent to which they contribute to gross farm production. The results of the multiple linear regressions showed that animal traction played a significant role in the total output of all the crops produced last season. The results of the t- tests showed that animal traction was the most effective technology compared to the simple hand-tools such as fork, fork spade and hoes. The binary logistic regression was employed to test the probability that resource poor households would adopt animal traction technology. It is therefore recommended that government should support animal traction users by providing all the necessary resources for development of animal in rural South Africa.
- Full Text:
- Date Issued: 2014
An evaluation of the effects of land tenure security in on-farm investment and on-farm productivity: a case of the smallholder farmers in the Amathole District of the Eastern Cape Province of South Africa
- Authors: Zwelendaba, Vincent Vusumzi
- Date: 2014
- Subjects: Land tenure -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11230 , http://hdl.handle.net/10353/d1021282 , Land tenure -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Description: Smallholder agriculture contributes to poverty alleviation through food price reduction and employment creation. Smallholder farmers have the potential of creating employment because they are labour-intensive. Most small holder farmers in the Amathole District practices dual farming system i.e. crops and livestock production. However these farmers are faced by a number of constraints amongst these are land tenure security, lack of capital, drought, diseases, lack of access to markets and production inputs. The objectives of this study were: to investigate land tenure security impact on-farm investment and on-farm productivity by the smallholder farmers; to assess constraints encountered by the smallholder farmers, to identify factors influencing on-farm investment by the smallholder farmers and to identify factors influencing on-farm productivity by the smallholder farmers. Eighty smallholder farmers were interviewed using a structured questionnaire. The data was analyzed using descriptive statistics (frequency, percentages) and regression analyses. Data was for coded and processed for analysis using Statistical Package for Social Sciences (SPSS). The results revealed that generally, the household demographic characteristics have an influence on the decision to investment in the farm thus on farm productivity. These included age, gender, marital status, educational level and household size of the smallholder farmers. However the findings revealed that smallholder farmers were not much concerned with the land tenure security of the land as they see themselves as owners of these lands. The reason being that they always had access to their land and there were no perceived tenure insecurity threats. The majority of the smallholder farmers were not worried that they might lose their land in the future as they felt that their land tenure was secured. Although, the majority of farmers had some sense of security they still preferred a freehold tenure system as form of land tenure security. This suggests that there was a sense of insecurity among some of the smallholder farmers caused by their current tenure forms. Majority (66%) of the farmers held their land under freehold whilst leasehold and communal hold farmers constituted 5 % and 29 % respectively. Even though majority had freehold tenure system, they could not use their land as collateral when required for funding from the lending institutions because the title deeds were not registered in their names but those of deceased family members. As a result the majority was constrained by lack of credit and had low income. Lack of cash suggests that the farmers have difficulties in purchasing farm of the survey suggest that the household demographics and socio-economic variables may have an influence on the on-farm investment and on-farm productivity by the smallholder farmers. Furthermore, besides the challenges with land tenure, there are other factors that are likely to influence on-farm investment and on-farm productivity. The results of the survey revealed that smallholder farmers were faced with lot of challenges. These included lack of access to markets, grazing land, credit, farm implements, productions inputs and irrigation water. In addition to this the smallholder farmers were faced with both crops and livestock production constraints. Crop production constraints included lack of access to labour, transport, capital, storage facilities, pests, diseases, lack of management skills and severe drought. Livestock production was constrained by diseases, theft, attack by wild animals, lack of fence in the camps, labour, vaccines, dipping facilities too far and severe drought. For both crop and livestock production diseases and drought were major concerns for smallholder farmers since they were dependent on rainfall for their farming activities. With regards to improvements and investment there was little or not much investment that has been made by the smallholder farmers. One of the reasons mentioned by the farmers as the main cause for little or no investments is the lack of capital to make such improvements or investments. The study also employed empirical analysis through employing on-farm investment and on-farm productivity models of the study on the factors influencing the on-farm investment and on-farm productivity by the smallholder farmers in the study area. In both models, the independent variables were tested for their significance and it was found that some variables were significant whilst others were not. With regards to the dependent variable on-farm investment, household socio-economic factors such as household size, educational levels and farm size, had a positive influence in on-farm investment and were also statistically significant. On the other side, factors such as land tenure security, age, gender, household income and access to markets did not have any influence and were not statistically significant. From the perspective of on-farm productivity variables such as farm size, access to credit and access to extension services had a positive influence. However, variables such as land tenure security, age, household income, educational levels, access to implements, were negatively influencing onfarm productivity by the smallholder farmers. Key words: Land tenure security, smallholder farmers, on-farm investment & on-farm productivity
- Full Text:
- Date Issued: 2014
- Authors: Zwelendaba, Vincent Vusumzi
- Date: 2014
- Subjects: Land tenure -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc Agric (Agricultural Economics)
- Identifier: vital:11230 , http://hdl.handle.net/10353/d1021282 , Land tenure -- South Africa -- Eastern Cape , Agricultural productivity -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Community development -- South Africa -- Eastern Cape
- Description: Smallholder agriculture contributes to poverty alleviation through food price reduction and employment creation. Smallholder farmers have the potential of creating employment because they are labour-intensive. Most small holder farmers in the Amathole District practices dual farming system i.e. crops and livestock production. However these farmers are faced by a number of constraints amongst these are land tenure security, lack of capital, drought, diseases, lack of access to markets and production inputs. The objectives of this study were: to investigate land tenure security impact on-farm investment and on-farm productivity by the smallholder farmers; to assess constraints encountered by the smallholder farmers, to identify factors influencing on-farm investment by the smallholder farmers and to identify factors influencing on-farm productivity by the smallholder farmers. Eighty smallholder farmers were interviewed using a structured questionnaire. The data was analyzed using descriptive statistics (frequency, percentages) and regression analyses. Data was for coded and processed for analysis using Statistical Package for Social Sciences (SPSS). The results revealed that generally, the household demographic characteristics have an influence on the decision to investment in the farm thus on farm productivity. These included age, gender, marital status, educational level and household size of the smallholder farmers. However the findings revealed that smallholder farmers were not much concerned with the land tenure security of the land as they see themselves as owners of these lands. The reason being that they always had access to their land and there were no perceived tenure insecurity threats. The majority of the smallholder farmers were not worried that they might lose their land in the future as they felt that their land tenure was secured. Although, the majority of farmers had some sense of security they still preferred a freehold tenure system as form of land tenure security. This suggests that there was a sense of insecurity among some of the smallholder farmers caused by their current tenure forms. Majority (66%) of the farmers held their land under freehold whilst leasehold and communal hold farmers constituted 5 % and 29 % respectively. Even though majority had freehold tenure system, they could not use their land as collateral when required for funding from the lending institutions because the title deeds were not registered in their names but those of deceased family members. As a result the majority was constrained by lack of credit and had low income. Lack of cash suggests that the farmers have difficulties in purchasing farm of the survey suggest that the household demographics and socio-economic variables may have an influence on the on-farm investment and on-farm productivity by the smallholder farmers. Furthermore, besides the challenges with land tenure, there are other factors that are likely to influence on-farm investment and on-farm productivity. The results of the survey revealed that smallholder farmers were faced with lot of challenges. These included lack of access to markets, grazing land, credit, farm implements, productions inputs and irrigation water. In addition to this the smallholder farmers were faced with both crops and livestock production constraints. Crop production constraints included lack of access to labour, transport, capital, storage facilities, pests, diseases, lack of management skills and severe drought. Livestock production was constrained by diseases, theft, attack by wild animals, lack of fence in the camps, labour, vaccines, dipping facilities too far and severe drought. For both crop and livestock production diseases and drought were major concerns for smallholder farmers since they were dependent on rainfall for their farming activities. With regards to improvements and investment there was little or not much investment that has been made by the smallholder farmers. One of the reasons mentioned by the farmers as the main cause for little or no investments is the lack of capital to make such improvements or investments. The study also employed empirical analysis through employing on-farm investment and on-farm productivity models of the study on the factors influencing the on-farm investment and on-farm productivity by the smallholder farmers in the study area. In both models, the independent variables were tested for their significance and it was found that some variables were significant whilst others were not. With regards to the dependent variable on-farm investment, household socio-economic factors such as household size, educational levels and farm size, had a positive influence in on-farm investment and were also statistically significant. On the other side, factors such as land tenure security, age, gender, household income and access to markets did not have any influence and were not statistically significant. From the perspective of on-farm productivity variables such as farm size, access to credit and access to extension services had a positive influence. However, variables such as land tenure security, age, household income, educational levels, access to implements, were negatively influencing onfarm productivity by the smallholder farmers. Key words: Land tenure security, smallholder farmers, on-farm investment & on-farm productivity
- Full Text:
- Date Issued: 2014
An integrated approach for the delineation of arable land and its cropping suitability under variable soil and climatic conditions in the Nkonkobe municipality, Eastern Cape, South Africa
- Authors: Manyevere, Alen
- Date: 2014
- Subjects: Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11965 , http://hdl.handle.net/10353/d1019856 , Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
- Description: Arable crop production in Nkonkobe Municipality is low due to abandonment of potentially productive land and low productivity of the cultivated land. Little attention has been given to farmers perspectives with regards to crop production and land abandonment. Understanding the relationships of indigenous knowledge systems, where local approaches to soil classification, appraisal, use and management and land evaluation, and scientific approaches could be important for the effective use of available soil resources while avoiding those resources that are vulnerable to degradation. In addition, the interactions between soil factors and climate could be useful in understanding the erodibility of soils. The intergration of scientific research and indigenous knowledge systems could help in the identification and delineation of high potential land and on crop suitability evaluation. The objectives of the study were: (i) to determine farmers‟ perspectives with regards to land utilisation and abandonment, constraints on crop production and crop preferences, (ii) to integrate and compare indigenous knowledge systems with scientific approaches of soil classification and potential, (iii) to determine the effect of climate and soil factors on erodibilities of soils in the Municipality (iv) to delineate arable land and evaluate its suitability for maize, potato, sorghum and cowpea under rainfed agriculture. Using semi-structured and open-ended interviews, information on limitations to crop production, cropping preferences, indigenous soil classifications, cropping potential ratings and erosion was captured. Descriptive and correlation statistics were used to analyse farmers‟ responses. The information was later used for a pilot participatory mapping and the determination of the agricultural potential of the soils in three selected villages of the Municipality. Field boundaries of soil texture, colour, depth, and slope position were captured using global positioning systems (GPS). The relationship between the degree of erosion and soil and slope factors was analysed by step-wise regression. Crop suitability for rainfed agriculture was done using the FAO guidelines for Land evaluation for rainfed agriculture. The spatially referenced crop suitability classes were produced by applying the Law of Limiting Combinationusing GIS Boolean Logic. The major biophysical factors, affecting crop production and land utilisation were soil degradation and low and erratic rainfall, while other factors included lack of farming equipment and security concerns. Maize, spinach and cabbage were the main crops grown, with maize sorghum and wheat the most abandoned crops. While it was difficult to accurately correlate indigenous classification with international scientific classification, the importance of colour, texture and soil depth for both classification and soil potential, suggests that some form of correlation is possible which enabled communication and other extension information to be conveyed. The shallow and stony soil (urhete) correlated well with the Leptosols in World Reference Base (WRB) or Mispah and shallow Glenrosa soils in the South African system. The red structured clays (umhlaba obomvu) matched the Nitisols in WRB or Shortlands in the South African system. The non-swelling black clayey soils (umhlaba omnyama) matched soils with melanic A horizons in both the WRB and South African soil classification systems. The dongwe and santi soils developed in alluvial sediments belonged to the Dundee, Oakleaf or Augrabies soils in the South African classification system and fluvisols or Cambisols in the WRB system. There was good agreement between farmers assessment of the cropping potential and scientific approaches but scientifically high potential red soils were rated lowly by the farmers due to difficulties in management caused by shortages of farm machinery, especially under dryland farming. Overall, the soil factors affecting erosion were influenced largely by climate, while parent material was also important. Climate had a dominant influence on soil factors most notably fine sand and very fine sand fractions and exchangeable sodium percentage being more important on soil forms occurring in arid and semi-arid climate and less in the sub-humid and humid areas, where clay mineralogy, particularly kaolinite and sesquioxide dominated. Dolerite derived soils were the most stable and should be given the highest priority for cropping development while mudstone and shale derived soils had a lower cropping potential. While slope gradient and length had some effect on soil erosion in arid and semi arid environments its influence was generally overshadowed by soil factors especially in humid zones. Cow pea and sorghum were the most adapted crops in the region while potato and maize were marginally suitable under rainfed agriculture. The study revealed that most adapted crops were not necessarily the most preferred crops by the farmers. A small percentage of the land was delineated as arable and therefore optimisation of this available land should be prioritized.
- Full Text:
- Date Issued: 2014
- Authors: Manyevere, Alen
- Date: 2014
- Subjects: Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Soil Science)
- Identifier: vital:11965 , http://hdl.handle.net/10353/d1019856 , Soils -- Classification -- South Africa -- Eastern Cape , Soil degradation -- South Africa -- Eastern Cape , Ethnoscience -- South Africa -- Eastern Cape
- Description: Arable crop production in Nkonkobe Municipality is low due to abandonment of potentially productive land and low productivity of the cultivated land. Little attention has been given to farmers perspectives with regards to crop production and land abandonment. Understanding the relationships of indigenous knowledge systems, where local approaches to soil classification, appraisal, use and management and land evaluation, and scientific approaches could be important for the effective use of available soil resources while avoiding those resources that are vulnerable to degradation. In addition, the interactions between soil factors and climate could be useful in understanding the erodibility of soils. The intergration of scientific research and indigenous knowledge systems could help in the identification and delineation of high potential land and on crop suitability evaluation. The objectives of the study were: (i) to determine farmers‟ perspectives with regards to land utilisation and abandonment, constraints on crop production and crop preferences, (ii) to integrate and compare indigenous knowledge systems with scientific approaches of soil classification and potential, (iii) to determine the effect of climate and soil factors on erodibilities of soils in the Municipality (iv) to delineate arable land and evaluate its suitability for maize, potato, sorghum and cowpea under rainfed agriculture. Using semi-structured and open-ended interviews, information on limitations to crop production, cropping preferences, indigenous soil classifications, cropping potential ratings and erosion was captured. Descriptive and correlation statistics were used to analyse farmers‟ responses. The information was later used for a pilot participatory mapping and the determination of the agricultural potential of the soils in three selected villages of the Municipality. Field boundaries of soil texture, colour, depth, and slope position were captured using global positioning systems (GPS). The relationship between the degree of erosion and soil and slope factors was analysed by step-wise regression. Crop suitability for rainfed agriculture was done using the FAO guidelines for Land evaluation for rainfed agriculture. The spatially referenced crop suitability classes were produced by applying the Law of Limiting Combinationusing GIS Boolean Logic. The major biophysical factors, affecting crop production and land utilisation were soil degradation and low and erratic rainfall, while other factors included lack of farming equipment and security concerns. Maize, spinach and cabbage were the main crops grown, with maize sorghum and wheat the most abandoned crops. While it was difficult to accurately correlate indigenous classification with international scientific classification, the importance of colour, texture and soil depth for both classification and soil potential, suggests that some form of correlation is possible which enabled communication and other extension information to be conveyed. The shallow and stony soil (urhete) correlated well with the Leptosols in World Reference Base (WRB) or Mispah and shallow Glenrosa soils in the South African system. The red structured clays (umhlaba obomvu) matched the Nitisols in WRB or Shortlands in the South African system. The non-swelling black clayey soils (umhlaba omnyama) matched soils with melanic A horizons in both the WRB and South African soil classification systems. The dongwe and santi soils developed in alluvial sediments belonged to the Dundee, Oakleaf or Augrabies soils in the South African classification system and fluvisols or Cambisols in the WRB system. There was good agreement between farmers assessment of the cropping potential and scientific approaches but scientifically high potential red soils were rated lowly by the farmers due to difficulties in management caused by shortages of farm machinery, especially under dryland farming. Overall, the soil factors affecting erosion were influenced largely by climate, while parent material was also important. Climate had a dominant influence on soil factors most notably fine sand and very fine sand fractions and exchangeable sodium percentage being more important on soil forms occurring in arid and semi-arid climate and less in the sub-humid and humid areas, where clay mineralogy, particularly kaolinite and sesquioxide dominated. Dolerite derived soils were the most stable and should be given the highest priority for cropping development while mudstone and shale derived soils had a lower cropping potential. While slope gradient and length had some effect on soil erosion in arid and semi arid environments its influence was generally overshadowed by soil factors especially in humid zones. Cow pea and sorghum were the most adapted crops in the region while potato and maize were marginally suitable under rainfed agriculture. The study revealed that most adapted crops were not necessarily the most preferred crops by the farmers. A small percentage of the land was delineated as arable and therefore optimisation of this available land should be prioritized.
- Full Text:
- Date Issued: 2014
An investigation on patient's perceptions regarding commencement of treatment following diagnosis with breast cancer at Frere Hospital, Buffalo City Metropolitan Municipality, Eastern Cape Province
- Ntombekaya, Matwele Caroline
- Authors: Ntombekaya, Matwele Caroline
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11927 , http://hdl.handle.net/10353/d1021305
- Description: The aim of the study was to: explore and describe patient’s perceptions regarding commencement of treatment following diagnosis with breast cancer at Frere Hospital in Buffalo City Metropolitan Municipality in the Eastern Cape, South Africa. Reasons why patients diagnosed with breast cancer delay in the commencement of the treatment were to be elicited and strategies for curbing the problem were looked into. A qualitative approach was used, with an exploratory, descriptive and contextual design. The purposive sampling technique was used. The sample comprised 15 participants, 14 Black Africans and 1 Coloured lady. Data were collected using an interview guide from female patients diagnosed with breast cancer whose age ranged from 18-72 years. Interviews were recorded on a tape. Tesch’s (1990) steps of qualitative data analysis guided the analysis process. The results revealed that being diagnosed with breast cancer is perceived as a traumatic and painful experience with negative emotional, social, physical impact and unbearable side effects of from the treatment. Fear of undergoing treatment emerged as a barrier for taking prompt treatment. In exploring, one needs to use empathy, particularly that the researcher engaged in bringing to surface painful information. With the use of understanding and broad mindedness, participants opened up. Recommendations were made regarding strategies for care.
- Full Text:
- Date Issued: 2014
- Authors: Ntombekaya, Matwele Caroline
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Nursing Science)
- Identifier: vital:11927 , http://hdl.handle.net/10353/d1021305
- Description: The aim of the study was to: explore and describe patient’s perceptions regarding commencement of treatment following diagnosis with breast cancer at Frere Hospital in Buffalo City Metropolitan Municipality in the Eastern Cape, South Africa. Reasons why patients diagnosed with breast cancer delay in the commencement of the treatment were to be elicited and strategies for curbing the problem were looked into. A qualitative approach was used, with an exploratory, descriptive and contextual design. The purposive sampling technique was used. The sample comprised 15 participants, 14 Black Africans and 1 Coloured lady. Data were collected using an interview guide from female patients diagnosed with breast cancer whose age ranged from 18-72 years. Interviews were recorded on a tape. Tesch’s (1990) steps of qualitative data analysis guided the analysis process. The results revealed that being diagnosed with breast cancer is perceived as a traumatic and painful experience with negative emotional, social, physical impact and unbearable side effects of from the treatment. Fear of undergoing treatment emerged as a barrier for taking prompt treatment. In exploring, one needs to use empathy, particularly that the researcher engaged in bringing to surface painful information. With the use of understanding and broad mindedness, participants opened up. Recommendations were made regarding strategies for care.
- Full Text:
- Date Issued: 2014