Multi-temporal analysis of urban land-use and land-cover patterns in Alice, Eastern Cape Province, South Africa
- Authors: Manyanye, Owen
- Date: 2017
- Subjects: Geographic information systems Land use -- Remote sensing Land cover
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8066 , vital:31506
- Description: South Africa is undergoing rapid urbanization coupled with fast demographic change in the major cities and towns. This economic shift leaves behind underdevelopment, particularly in the rural areas such as the Eastern Cape Province. Underdevelopment of rural Eastern Cape can be understood by revisiting the “native reserve policy” of the Union of South Africa (1910 –1948) and the separate development policies of the apartheid government (1948 –1994). These policies have induced landlessness in the rural Eastern Cape and the destruction of rural livelihoods, poverty and under-development of roads, housing, health, education and sanitation facilities, and constrained development of a sustainable local economy. This study was aimed at determining the temporal and spatial land-use / land-cover changes in and around Alice town in the Eastern Cape Province of South Africa by using multi-date remotely Landsat TM images covering 5 time slices for the years 1984, 1989, 1994, 1999 and 2009. This was done by using supervised classification to objectively reconstruct changes in land-use and land-cover by compiling time-series maps with four information classes and using the Kappa Coefficient to assess the accuracy of all map outputs. Results of this investigation point to significant changes in land-use and land-cover over the 25-year study period between 1984 and 2009 with built-up areas expanding by 3720 hectares from 3227 hectares in 1984 to 6947 hectares in 2009. This observation is important because it enhances our understanding of the dynamics of urban growth and provides useful insights that aid urban development planning and policy formulation. The research concludes by recommending the use time series remotely sensed imagery as a decision-support tool for urban and environment management.
- Full Text:
- Date Issued: 2017
- Authors: Manyanye, Owen
- Date: 2017
- Subjects: Geographic information systems Land use -- Remote sensing Land cover
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8066 , vital:31506
- Description: South Africa is undergoing rapid urbanization coupled with fast demographic change in the major cities and towns. This economic shift leaves behind underdevelopment, particularly in the rural areas such as the Eastern Cape Province. Underdevelopment of rural Eastern Cape can be understood by revisiting the “native reserve policy” of the Union of South Africa (1910 –1948) and the separate development policies of the apartheid government (1948 –1994). These policies have induced landlessness in the rural Eastern Cape and the destruction of rural livelihoods, poverty and under-development of roads, housing, health, education and sanitation facilities, and constrained development of a sustainable local economy. This study was aimed at determining the temporal and spatial land-use / land-cover changes in and around Alice town in the Eastern Cape Province of South Africa by using multi-date remotely Landsat TM images covering 5 time slices for the years 1984, 1989, 1994, 1999 and 2009. This was done by using supervised classification to objectively reconstruct changes in land-use and land-cover by compiling time-series maps with four information classes and using the Kappa Coefficient to assess the accuracy of all map outputs. Results of this investigation point to significant changes in land-use and land-cover over the 25-year study period between 1984 and 2009 with built-up areas expanding by 3720 hectares from 3227 hectares in 1984 to 6947 hectares in 2009. This observation is important because it enhances our understanding of the dynamics of urban growth and provides useful insights that aid urban development planning and policy formulation. The research concludes by recommending the use time series remotely sensed imagery as a decision-support tool for urban and environment management.
- Full Text:
- Date Issued: 2017
Multi-temporal assessment of spatial changes in vegetation distribution in the Swartkops estuary, Port Elizabeth, Eastern Cape, South Africa
- Authors: Atyosi, Yonwaba
- Date: 2017
- Subjects: Climatic changes -- South Africa -- Eastern Cape Environmental impact analysis Estuaries -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13762 , vital:39710
- Description: Over the last decade, image classification has been widely used as a change detection method and provides detailed information for detecting and monitoring changes in land use and land cover (LULC). The main objective of this study was to reconstruct long-term changes in the spatial distribution of different vegetation types in the Swartkops Estuary from 1983 to 2013. The Swartkops Estuary is ecologically important for its wide range of vegetation types that are habitat to estuarine and riverine organisms. Four Landsat images for the years 1984 (Thematic Mapper), 1993 (Thematic Mapper), 2003(Enhanced Thematic Mapper +) and 2013 (Operational Land Imager) were used with the aid of aerial photographs that were used as an ancillary data source. The research methodology comprised of supervised classification, classification accuracy assessment and image differencing. Supervised classification was performed and results of the image classification process for the four time periods were compared to derive information on changes that occurred over the 29-year study period. Images were classified into the following classes: Estuarine water, Salt works, Zostera capensis, Spartina maritima, Terrestrial vegetation, Salt marsh, Swartkops thicket, Built-up areas, Bare areas, and Beach sand, using the Maximum likelihood classifier on Erdas IMAGINE 2014 Software. The significance of the image classification was tested using linear trend regression analysis. Image differencing was performed using 1984 and 2013 Landsat images to reconstruct overall changes in vegetation distribution of the Swartkops Estuary. Results of this investigation revealed significant changes in all land cover types, 24 ha increase from 1984 to 2013 in Zostera capensis as well as Spartina maritima, salt marshes increased by 14 ha between 1984 and 2013, terrestrial vegetation declined by 18 ha between 1984 and 2013. There was a stable increase in estuarine water from 1984 to 2013 by a total area of 29 ha. Water increased by 14 ha between 1984 and 1993, 11 ha increase between 1993 and 2003. However, there was a decline in estuarine water in the period between 2003 and 2013.This decline is associated with the increase in submerged macrophytes like Zostera capensis which utilise open water habitat. The dominant salt marsh species Limonium peregrinum, Sarcoconia pillansii and Spartina maritima occurred in the intertidal, supratidal and floodplain areas where the water table was the shallowest, with the soil moisture being the highest. These results indicate that Remote Sensing and GIS can be effectively used to detect and monitor changes in estuarine biodiversity and habitat in South Africa.
- Full Text:
- Date Issued: 2017
- Authors: Atyosi, Yonwaba
- Date: 2017
- Subjects: Climatic changes -- South Africa -- Eastern Cape Environmental impact analysis Estuaries -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13762 , vital:39710
- Description: Over the last decade, image classification has been widely used as a change detection method and provides detailed information for detecting and monitoring changes in land use and land cover (LULC). The main objective of this study was to reconstruct long-term changes in the spatial distribution of different vegetation types in the Swartkops Estuary from 1983 to 2013. The Swartkops Estuary is ecologically important for its wide range of vegetation types that are habitat to estuarine and riverine organisms. Four Landsat images for the years 1984 (Thematic Mapper), 1993 (Thematic Mapper), 2003(Enhanced Thematic Mapper +) and 2013 (Operational Land Imager) were used with the aid of aerial photographs that were used as an ancillary data source. The research methodology comprised of supervised classification, classification accuracy assessment and image differencing. Supervised classification was performed and results of the image classification process for the four time periods were compared to derive information on changes that occurred over the 29-year study period. Images were classified into the following classes: Estuarine water, Salt works, Zostera capensis, Spartina maritima, Terrestrial vegetation, Salt marsh, Swartkops thicket, Built-up areas, Bare areas, and Beach sand, using the Maximum likelihood classifier on Erdas IMAGINE 2014 Software. The significance of the image classification was tested using linear trend regression analysis. Image differencing was performed using 1984 and 2013 Landsat images to reconstruct overall changes in vegetation distribution of the Swartkops Estuary. Results of this investigation revealed significant changes in all land cover types, 24 ha increase from 1984 to 2013 in Zostera capensis as well as Spartina maritima, salt marshes increased by 14 ha between 1984 and 2013, terrestrial vegetation declined by 18 ha between 1984 and 2013. There was a stable increase in estuarine water from 1984 to 2013 by a total area of 29 ha. Water increased by 14 ha between 1984 and 1993, 11 ha increase between 1993 and 2003. However, there was a decline in estuarine water in the period between 2003 and 2013.This decline is associated with the increase in submerged macrophytes like Zostera capensis which utilise open water habitat. The dominant salt marsh species Limonium peregrinum, Sarcoconia pillansii and Spartina maritima occurred in the intertidal, supratidal and floodplain areas where the water table was the shallowest, with the soil moisture being the highest. These results indicate that Remote Sensing and GIS can be effectively used to detect and monitor changes in estuarine biodiversity and habitat in South Africa.
- Full Text:
- Date Issued: 2017
Perceptions of rural households about the role and effect of biogas production on rural household income in Raymond Mhlaba Local Municipality
- Authors: Ngcobo, Lindiwe
- Date: 2017
- Subjects: Biomass energy -- South Africa -- Eastern Cape Renewable energy sources -- South Africa -- Eastern Cape Sustainable living -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4694 , vital:28494
- Description: Rural development efforts to reduce poverty and enhance food security and generally improve livelihoods in developing countries continue to be constrained by high energy cost. For that reason, renewable energy has been identified as a possible panacea to fill this gap. Renewable energy is cheaper, more accessible and environmentally sustainable and promotes inclusivity. Biogas is a renewable energy that is readily available and easy to use by poor rural households. The use of biogas digesters among households in rural areas of developing countries is a well-known technology. The potential for biogas in these areas has been demonstrated and a strong economic case has been made. However, its adoption and use have been lower than expectations possibly as result of non-economic considerations, including social issues about which rural people hold different perceptions. Perceptions of rural households are important because they influence the behaviour to a large extent. Since limited access to affordable energy in rural areas has encouraged government and private organisations to initiate biogas projects to overcome the challenge, it is important to ascertain the factors that affect attitudes towards the technology. The present study sought to explore perceptions of rural households about biogas production towards rural household income in the Raymond Mhlaba Local Municipality. Specifically, this research investigated the state of biogas project being implemented by the University of Fort Hare’s Institute of Technology (FHIT), the perceptions of respondents towards biogas production and determine the contribution of biogas consumption to rural income. The study also aimed to identify the factors affecting the adoption of biogas production in the study area. The study was carried out in Melani village in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa and employed survey data obtained from 48 households who were enumerated to identify their perceptions on biogas production, with special emphasis on the role and effect contributed to rural income of Melani village. The study employed a cross-sectional research design and purposive sampling technique was used in data collection. Data were collected and captured in Excel and then analysed using the statistical package for social sciences (SPSS) Version 24 Descriptive statistics was used to examine socio-economic characteristics of households and state of biogas production in the area, Bivariate correlation analysis was used to determine the relationships among the key elements of perceptions of household towards biogas adoption, binary logistic model was used to estimate factors influencing adoption of biogas technology by households. The results show that women were dominant for both adopters and non-adopters of biogas. The majority of households were young with mean age of 40 years while for non-adopters were 65 years old on average. The results showed high levels of literacy amongst household adopters. Majority of the households for both adopters and non-adopters of biogas technology were married and unemployed and household size ranged from one to five persons, with social grants being dominant source of income. The bivariate correlation analysis suggests a positive effect of green pepper production and livestock ownership on biogas technology adoption. Age and level of education were negatively correlated with adoption of biogas. The cross tabulation analysis suggests that water scarcity, lack of knowledge about biogas technology, cattle ownership, lack of maintenance and repairing, flooded biogas digesters during rainy season are negatively associated with the uptake of biogas technology. The empirical results from binary logistic model suggest that land size was the key determinant of adoption behaviour towards biogas technology while age of the household head, source of income and level of education may have a negative influence on adoption of biogas technology. Based on the findings highlighted above, the study recommends strategies to encourage households to adopt biogas technology.
- Full Text:
- Date Issued: 2017
- Authors: Ngcobo, Lindiwe
- Date: 2017
- Subjects: Biomass energy -- South Africa -- Eastern Cape Renewable energy sources -- South Africa -- Eastern Cape Sustainable living -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4694 , vital:28494
- Description: Rural development efforts to reduce poverty and enhance food security and generally improve livelihoods in developing countries continue to be constrained by high energy cost. For that reason, renewable energy has been identified as a possible panacea to fill this gap. Renewable energy is cheaper, more accessible and environmentally sustainable and promotes inclusivity. Biogas is a renewable energy that is readily available and easy to use by poor rural households. The use of biogas digesters among households in rural areas of developing countries is a well-known technology. The potential for biogas in these areas has been demonstrated and a strong economic case has been made. However, its adoption and use have been lower than expectations possibly as result of non-economic considerations, including social issues about which rural people hold different perceptions. Perceptions of rural households are important because they influence the behaviour to a large extent. Since limited access to affordable energy in rural areas has encouraged government and private organisations to initiate biogas projects to overcome the challenge, it is important to ascertain the factors that affect attitudes towards the technology. The present study sought to explore perceptions of rural households about biogas production towards rural household income in the Raymond Mhlaba Local Municipality. Specifically, this research investigated the state of biogas project being implemented by the University of Fort Hare’s Institute of Technology (FHIT), the perceptions of respondents towards biogas production and determine the contribution of biogas consumption to rural income. The study also aimed to identify the factors affecting the adoption of biogas production in the study area. The study was carried out in Melani village in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa and employed survey data obtained from 48 households who were enumerated to identify their perceptions on biogas production, with special emphasis on the role and effect contributed to rural income of Melani village. The study employed a cross-sectional research design and purposive sampling technique was used in data collection. Data were collected and captured in Excel and then analysed using the statistical package for social sciences (SPSS) Version 24 Descriptive statistics was used to examine socio-economic characteristics of households and state of biogas production in the area, Bivariate correlation analysis was used to determine the relationships among the key elements of perceptions of household towards biogas adoption, binary logistic model was used to estimate factors influencing adoption of biogas technology by households. The results show that women were dominant for both adopters and non-adopters of biogas. The majority of households were young with mean age of 40 years while for non-adopters were 65 years old on average. The results showed high levels of literacy amongst household adopters. Majority of the households for both adopters and non-adopters of biogas technology were married and unemployed and household size ranged from one to five persons, with social grants being dominant source of income. The bivariate correlation analysis suggests a positive effect of green pepper production and livestock ownership on biogas technology adoption. Age and level of education were negatively correlated with adoption of biogas. The cross tabulation analysis suggests that water scarcity, lack of knowledge about biogas technology, cattle ownership, lack of maintenance and repairing, flooded biogas digesters during rainy season are negatively associated with the uptake of biogas technology. The empirical results from binary logistic model suggest that land size was the key determinant of adoption behaviour towards biogas technology while age of the household head, source of income and level of education may have a negative influence on adoption of biogas technology. Based on the findings highlighted above, the study recommends strategies to encourage households to adopt biogas technology.
- Full Text:
- Date Issued: 2017
Performance comparison of iron pillared montmorillonite, raw and modified zeolites sorption for Cu(II), Pb(II) and Ni(II) in water
- Authors: Madigoe, Marakeng Rhudolf
- Date: 2017
- Subjects: Water -- Purification -- Biological treatment Adsorption Montmorillonite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8078 , vital:31516
- Description: The higher concentration of heavy metals and pollutants is toxic to human health and the environment. It is essential to remove these toxics from contaminated water. There are several methods developed for water treatment. These include adsorption, reverse osmosis, precipitation, coagulation and cation exchange. Adsorbents of various characteristics are considered for removal of heavy metals and pollutants. The study investigated the performance of iron pillared Montmorillonite, raw and modified zeolite (acid and base) for the removal of Cu(II), Pb(II) and Ni(II) in artificially contaminated water. The adsorbents were characterized by X-ray Diffraction (XRD), Fourier Transformation Infrared spectroscopy (FTIR) and Scanning Electron Microscope (SEM) instruments. The percentage removal of Cu(II), Pb(II) and Ni(II) after adsorption process were determined. Iron pillared Montmorillonite showed efficient removal for lead and zeolite for copper and nickel.
- Full Text:
- Date Issued: 2017
- Authors: Madigoe, Marakeng Rhudolf
- Date: 2017
- Subjects: Water -- Purification -- Biological treatment Adsorption Montmorillonite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8078 , vital:31516
- Description: The higher concentration of heavy metals and pollutants is toxic to human health and the environment. It is essential to remove these toxics from contaminated water. There are several methods developed for water treatment. These include adsorption, reverse osmosis, precipitation, coagulation and cation exchange. Adsorbents of various characteristics are considered for removal of heavy metals and pollutants. The study investigated the performance of iron pillared Montmorillonite, raw and modified zeolite (acid and base) for the removal of Cu(II), Pb(II) and Ni(II) in artificially contaminated water. The adsorbents were characterized by X-ray Diffraction (XRD), Fourier Transformation Infrared spectroscopy (FTIR) and Scanning Electron Microscope (SEM) instruments. The percentage removal of Cu(II), Pb(II) and Ni(II) after adsorption process were determined. Iron pillared Montmorillonite showed efficient removal for lead and zeolite for copper and nickel.
- Full Text:
- Date Issued: 2017
Performance of a residential swimming pool air source heat pump water heater installed in Fort Beaufort, South Africa
- Authors: Mqayi, Singatha
- Date: 2017
- Subjects: Water heaters Heat pumps Swimming pools -- Heating and ventilation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4835 , vital:28532
- Description: Globally, there is growing concern about energy consumption and its diverse effects on the environment. In South Africa, the current status quo is unfavourable in the domain of energy, hence the Department of Energy, Eskom and NERSA have embarked on supporting energy efficiency technologies nationwide as a strategic goal in reducing demand on the national grid. Due to the non conservative consumption of electricity from the grid and the insufficient supply to meet its demand, the importation of crude oil is very certain. In addition, the current and most popular technology for pool water heating in the said country is the resistive element which is inefficient and non-cost-effective. The energy consumption of residential swimming pool water heating is very massive, and tariff structure shows a constant rise. Furthermore, there's a current electricity crisis during the Eskom evening peak. Hence, a reliable, efficient, cost-effective and renewable energy technology such as an air source heat pump is required as a retrofit to the existing resistive element. Furthermore, mathematical modelling is a tool that can be used to mimic the dynamic behaviour of a physical or process system. It is a computational language or mathematical equation used to predict the dynamic behaviour of physical systems [Tangwe et al., 2015]. Various methods such as numerical methods have been considered as the particular types of mathematical modelling which have been employed to predict the performance of swimming pool ASHP water heater. However, they were unreliable and expensive. Consequently, this research focused on the experimental determination of the viability and development of a mathematical model to predict the performance of swimming pool ASHP water heater. The benefit of the development and building of this model was attributed to its low cost and credibility to forecast the performance of swimming pool ASHP water heater. Also, this robust mathematical model can be used by an energy service company and system manufacturer to compute the dynamic coefficient of performance of the swimming pool ASHP water heater. Following the above-mentioned information, the research sought to provide a permanent solution to the Eskom evening peak constraint. This is because energy-efficiency, serves as the bridging block between conventional and renewable energy sources needed by Eskom in a bid to provide a balance energy mix and sustainable energy. The implementation of a swimming pool ASHP water heater guaranteed a conducive environment for the population due to the reduction in environmental pollution.
- Full Text:
- Date Issued: 2017
- Authors: Mqayi, Singatha
- Date: 2017
- Subjects: Water heaters Heat pumps Swimming pools -- Heating and ventilation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4835 , vital:28532
- Description: Globally, there is growing concern about energy consumption and its diverse effects on the environment. In South Africa, the current status quo is unfavourable in the domain of energy, hence the Department of Energy, Eskom and NERSA have embarked on supporting energy efficiency technologies nationwide as a strategic goal in reducing demand on the national grid. Due to the non conservative consumption of electricity from the grid and the insufficient supply to meet its demand, the importation of crude oil is very certain. In addition, the current and most popular technology for pool water heating in the said country is the resistive element which is inefficient and non-cost-effective. The energy consumption of residential swimming pool water heating is very massive, and tariff structure shows a constant rise. Furthermore, there's a current electricity crisis during the Eskom evening peak. Hence, a reliable, efficient, cost-effective and renewable energy technology such as an air source heat pump is required as a retrofit to the existing resistive element. Furthermore, mathematical modelling is a tool that can be used to mimic the dynamic behaviour of a physical or process system. It is a computational language or mathematical equation used to predict the dynamic behaviour of physical systems [Tangwe et al., 2015]. Various methods such as numerical methods have been considered as the particular types of mathematical modelling which have been employed to predict the performance of swimming pool ASHP water heater. However, they were unreliable and expensive. Consequently, this research focused on the experimental determination of the viability and development of a mathematical model to predict the performance of swimming pool ASHP water heater. The benefit of the development and building of this model was attributed to its low cost and credibility to forecast the performance of swimming pool ASHP water heater. Also, this robust mathematical model can be used by an energy service company and system manufacturer to compute the dynamic coefficient of performance of the swimming pool ASHP water heater. Following the above-mentioned information, the research sought to provide a permanent solution to the Eskom evening peak constraint. This is because energy-efficiency, serves as the bridging block between conventional and renewable energy sources needed by Eskom in a bid to provide a balance energy mix and sustainable energy. The implementation of a swimming pool ASHP water heater guaranteed a conducive environment for the population due to the reduction in environmental pollution.
- Full Text:
- Date Issued: 2017
Physiochemical and heavy metals fingerprints of the final effluents of Adelaide and Seymour wastewater treatment facilities in the Eastern Cape, South Africa
- Authors: Mutukwa, Dorcas
- Date: 2017
- Subjects: Water -- Purification Effluent quality -- Testing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8089 , vital:31520
- Description: Wastewater contains pathogens, heavy metals, nutrients, organic matter and other toxic chemicals and when discharged into the environment without proper treatment, it may cause adverse health problems and environment degradation. There have been reports in the Eastern Cape Province, South Africa of inadequate treated wastewater effluents being discharged into freshwater environments. This study reports on the physicochemical and heavy metals qualities for two wastewater treatment facilities in the Eastern Cape, South Africa over a six-month sampling period (September 2015 to February 2016). Wastewater effluent samples were collected from the influents, final effluents and receiving waterbodies as well as sludge samples in replicates. The physicochemical parameters were analysed using standard methods (APHA, 2012). The acid digested heavy metals samples were analysed using Atomic Absorption Spectrophotometer (iCE 3500 Thermo Fisher Spectrometer). The concentrations were compared to recommended limits used in South Africa and World Health Organisation (WHO). Physicochemical qualities assessed at Adelaide wastewater treatment plant ranged as follows: temperature (21.6 - 30.5 oC), turbidity (2.1 – 71.3 NTU), electrical conductivity (EC) (743.0 – 898.3 μ/Scm) and dissolved oxygen (DO) (2.11 – 3.50 mg/L) while the ranges of the parameter assessed at Seymour wastewater treatment plant ranged as follows: chemical dissolved oxygen (COD) (41.7 – 115.3 mg/L), EC (628 and 797.7 μ/Scm) and nitrates (4.6 – 11.0 mg/L. The heavy metals concentration for the final effluents at Adelaide wastewater treatment plant ranged as follows: Cd (0 – 0.002 mg/L), Cu (0 – 0.096 mg/L) and Fe (0 – 0.498 mg/L). Cu concentrations in sludge at Seymour wastewater treatment plant ranged between 83.82 and 132.07 mg/L. Reduction efficiencies of Adelaide in removing chlorides and sulphates were 33 and 36 percent respectively. Findings of study revealed negative impacts of inadequately treated effluents on receiving waterbodies and this puts communities which rely on the water as immediate source of fresh water for domestic purposes at health risk.
- Full Text:
- Date Issued: 2017
- Authors: Mutukwa, Dorcas
- Date: 2017
- Subjects: Water -- Purification Effluent quality -- Testing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8089 , vital:31520
- Description: Wastewater contains pathogens, heavy metals, nutrients, organic matter and other toxic chemicals and when discharged into the environment without proper treatment, it may cause adverse health problems and environment degradation. There have been reports in the Eastern Cape Province, South Africa of inadequate treated wastewater effluents being discharged into freshwater environments. This study reports on the physicochemical and heavy metals qualities for two wastewater treatment facilities in the Eastern Cape, South Africa over a six-month sampling period (September 2015 to February 2016). Wastewater effluent samples were collected from the influents, final effluents and receiving waterbodies as well as sludge samples in replicates. The physicochemical parameters were analysed using standard methods (APHA, 2012). The acid digested heavy metals samples were analysed using Atomic Absorption Spectrophotometer (iCE 3500 Thermo Fisher Spectrometer). The concentrations were compared to recommended limits used in South Africa and World Health Organisation (WHO). Physicochemical qualities assessed at Adelaide wastewater treatment plant ranged as follows: temperature (21.6 - 30.5 oC), turbidity (2.1 – 71.3 NTU), electrical conductivity (EC) (743.0 – 898.3 μ/Scm) and dissolved oxygen (DO) (2.11 – 3.50 mg/L) while the ranges of the parameter assessed at Seymour wastewater treatment plant ranged as follows: chemical dissolved oxygen (COD) (41.7 – 115.3 mg/L), EC (628 and 797.7 μ/Scm) and nitrates (4.6 – 11.0 mg/L. The heavy metals concentration for the final effluents at Adelaide wastewater treatment plant ranged as follows: Cd (0 – 0.002 mg/L), Cu (0 – 0.096 mg/L) and Fe (0 – 0.498 mg/L). Cu concentrations in sludge at Seymour wastewater treatment plant ranged between 83.82 and 132.07 mg/L. Reduction efficiencies of Adelaide in removing chlorides and sulphates were 33 and 36 percent respectively. Findings of study revealed negative impacts of inadequately treated effluents on receiving waterbodies and this puts communities which rely on the water as immediate source of fresh water for domestic purposes at health risk.
- Full Text:
- Date Issued: 2017
Physiochemical, fatty acids, lipid oxidation, sensory characteristics and consumer acceptance of warthog cabanossi produced with pork backfat and fat-tailed sheep backfat
- Authors: Mahachi, Leo Nyikadzino
- Date: 2017
- Subjects: Fatty acids Lipids -- Oxidation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6259 , vital:29530
- Description: The objective of this study was to determine the effect of different fat inclusion levels and fat types on the physical and chemical attributes, lipid oxidation, fatty acid composition and sensory characteristics of warthog cabanossi. To achieve this, three types of cabanossi with different pork backfat levels (10 percent, 20 percent and 30 percent) were produced for the first experiment. The results from the study showed that different inclusion levels of pork backfat had an influence (P ≤ 0.05) on the physicochemical and fatty acid composition of warthog cabanossi but did not influence lipid oxidation (P > 0.05). The highest (P ≤0.05) pH, weight and moisture decline was observed in the 10 percent pork backfat cabanossi compared to the 20 percent and 30 percent treatments. However, no differences (P > 0.05) in the water activity of the product were observed. As expected total fat was lower in the 10 percent fat treatment and increased concomitantly. Similarly, protein, ash and salt were higher in the 10 percent fat cabanossi and decreased concomitantly. Differences in the fatty acid composition were observed between treatments. Furthermore, backfat level affected the sensory attributes and consumer acceptance of the cabanossi. Ten percent backfat cabanossi was scored higher (P ≤0.05) for most sensory attributes. Consequently, it was observed that the consumer panel preferred and scored the 10 percent fat cabanossi higher with regards to appearance and taste. In the second experiment, two cabanossi treatments of different fat types (pork backfat and fat-tailed sheep backfat) were produced. The weight loss, moisture content, pH, water activity and salt content did not differ (P > 0.05) between the two cabanossi products. However, there were differences (P ≤0.05) in the protein, fat and ash contents; where protein and ash were higher in the pork backfat cabanossi whilst fat was higher in the sheep backfat cabanossi. Thiobarbituric reactive substances (TBARS) were similar (P > 0.05) between the two fat types cabanossi which could be explained by similar fatty acid profiles being reported for the two cabanossi although the n-6:n-3 ratio was higher (P ≤0.05) in sheep backfat cabanossi. Results from the descriptive sensory analysis showed two distinct products (P ≤0.01) where pork backfat cabanossi scored higher for most attributes. However, the lower scores for sheep backfat cabanossi were within an acceptable range. Sheep backfat cabanossi were also scored for unique attributes that were not detected in the pork backfat cabanossi. This study concluded that fat-tailed sheep backfat can be used to produce an unique cabanossi product of acceptable quality.
- Full Text:
- Date Issued: 2017
- Authors: Mahachi, Leo Nyikadzino
- Date: 2017
- Subjects: Fatty acids Lipids -- Oxidation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6259 , vital:29530
- Description: The objective of this study was to determine the effect of different fat inclusion levels and fat types on the physical and chemical attributes, lipid oxidation, fatty acid composition and sensory characteristics of warthog cabanossi. To achieve this, three types of cabanossi with different pork backfat levels (10 percent, 20 percent and 30 percent) were produced for the first experiment. The results from the study showed that different inclusion levels of pork backfat had an influence (P ≤ 0.05) on the physicochemical and fatty acid composition of warthog cabanossi but did not influence lipid oxidation (P > 0.05). The highest (P ≤0.05) pH, weight and moisture decline was observed in the 10 percent pork backfat cabanossi compared to the 20 percent and 30 percent treatments. However, no differences (P > 0.05) in the water activity of the product were observed. As expected total fat was lower in the 10 percent fat treatment and increased concomitantly. Similarly, protein, ash and salt were higher in the 10 percent fat cabanossi and decreased concomitantly. Differences in the fatty acid composition were observed between treatments. Furthermore, backfat level affected the sensory attributes and consumer acceptance of the cabanossi. Ten percent backfat cabanossi was scored higher (P ≤0.05) for most sensory attributes. Consequently, it was observed that the consumer panel preferred and scored the 10 percent fat cabanossi higher with regards to appearance and taste. In the second experiment, two cabanossi treatments of different fat types (pork backfat and fat-tailed sheep backfat) were produced. The weight loss, moisture content, pH, water activity and salt content did not differ (P > 0.05) between the two cabanossi products. However, there were differences (P ≤0.05) in the protein, fat and ash contents; where protein and ash were higher in the pork backfat cabanossi whilst fat was higher in the sheep backfat cabanossi. Thiobarbituric reactive substances (TBARS) were similar (P > 0.05) between the two fat types cabanossi which could be explained by similar fatty acid profiles being reported for the two cabanossi although the n-6:n-3 ratio was higher (P ≤0.05) in sheep backfat cabanossi. Results from the descriptive sensory analysis showed two distinct products (P ≤0.01) where pork backfat cabanossi scored higher for most attributes. However, the lower scores for sheep backfat cabanossi were within an acceptable range. Sheep backfat cabanossi were also scored for unique attributes that were not detected in the pork backfat cabanossi. This study concluded that fat-tailed sheep backfat can be used to produce an unique cabanossi product of acceptable quality.
- Full Text:
- Date Issued: 2017
Prevalence of Group B streptococcus and staphylococcus aureus colonization in the anogenital tract of pregnant women in the Eastern Cape Province, South Africa
- Authors: Stofile, P Z
- Date: 2017
- Subjects: Streptococcal infections Staphylococcus aureus
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5983 , vital:29462
- Description: Neonatal sickness and death is increasingly becoming a public health problem worldwide. The colonization of Group B Streptococcus and Staphylococcus in the rectovaginal area is among the sources of infections in neonates which can result in illness and mortality. The over exposure of humans to antibiotics is the possible cause of resistance in bacteria. These resistant strains can be passed onto offspring, leading to resistant infections and increasing the morbidity of neonates because of treatment failures. Many people, including healthcare personnel are not aware of the effect of these bacteria, and informing clinics and hospitals can help create awareness and monitoring the levels of resistance among bacteria can assist in preventing the transference of the bacteria. In this study we investigated the prevalence of group B Streptococcus (GBS) and Staphylococcus aureus in the anogenital tract of pregnant women in the Eastern Cape Province, South Africa. A total of 49 isolates from 25 (30.5 percent) pregnant women colonized with GBS were isolated from vaginal and rectal swabs of 82 pregnant women at 25-37 gestation who participated in this study. These isolates were obtained using standard microbiological methods and confirmed by polymerase chain reaction (PCR) technique aimed at the ScpB gene. The isolates were further screened for the presence of 9 serogroups (Ia, Ib, II, III, IV, V, VI, VII, VII) and serogroups Ib 2 (4.8 percent), II 20 (40.8 percent) and IV 5 (10.2 percent) and 22 non-typable (44.9 percent) were identified. Susceptibility profiling of the isolates to 12 antibiotics (tetracycline, clindamycin, erythromycin, gentamycin, naladixic acid, norfloxacin, chloramphenicol, cefuroxime, cefotaxime, imipenem, penicillin and vancomycin) was tested in vitro by the standardized disc diffusion method. All the confirmed GBS isolates (49) were resistant to erythromycin, tetracycline and clindamycin. A higher percentage of the isolates were resistant to gentamycin 44 (90 percent), nalidixic acid 41 (84 percent), penicillin 41 (84 percent), chloramphenicol 38 (78 percent), cefuroxime 36 (74 percent), imipenem 36 (74 percent), cefotaxime 35 (71 percent), norfloxacin 32 (65 percent) and vancomycin 31 (78 percent). Multiple antimicrobial resistance patterns ranged from 9‒11 and indices ranged from 0.7‒0.9, respectively. Among the antimicrobial resistance determinants examined, genes encoding for resistance to erythromycin ermB 25 (51 percent), tetracycline tetM 32 (65 percent) and penicillin bla-Z 4 (8 percent) only were identified. On the other hand, screening for S. aureus yielded a total of 7 isolates from 4 study participants as confirmed by PCR based on staphylococcal, nuc gene. The isolates were further screened for the presence of six virulence genes (Hla, Hlb, LUKM, LUKED, PVL, Eta and Etb) and antibiotic susceptibility pattern by the disc diffusion method using 12 (penicillin, vancomycin, tetracycline, rifampicin, imipenem, gentamycin, chloramphenicol, norfloxacin, oxacillin, erythromycin and sulfamethoxazole-trimethoprim) antibiotics that are adopted in the treatment of infections caused by the organism. PVL 6 (85.7 percent) and eta 1 (14.3 percent) were the two virulence genes detected. The following percentages of antibiotics resistance among the isolates were observed; penicillin G 7 (100 percent), clindamycin 7 (100 percent), vancomycin 5 (100 percent), rifampicin 5 (71 percent), oxacillin 5 (71 percent), erythromycin 5 (71 percent) gentamycin 3 (43 percent), norfloxacin 3 (43 percent), sulfamethoxazole-trimethoprim 3 (43 percent), chloramphenicol 2 (29 percent), imipenem 1 (14 percent). Multiple antimicrobial resistance patterns ranged from 7‒8 and indices ranged from 0.6‒0.7, respectively. Genetic profiling of the resistance genes identified erythromycin ermB 5(71.4 percent), tetracycline tetM 5(71.4 percent) and penicillin bla-Z 1(14.3 percent) only. The findings from the study have revealed GBS and S. aureus colonization of pregnant women in the Eastern Cape Province, and these have great public health implications especially for the neonates who are mostly likely to be infected during birth. The unidentifiable multidrug resistant serogroups of GBS as well as resistant S. aureus limit the choice of drugs in the management of infections caused by these pathogens more so if transmitted to infants. Therefore asymptomatic pregnant women needed to be properly educated about the bacteria as well as the precautions that need to be taken.
- Full Text:
- Date Issued: 2017
- Authors: Stofile, P Z
- Date: 2017
- Subjects: Streptococcal infections Staphylococcus aureus
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5983 , vital:29462
- Description: Neonatal sickness and death is increasingly becoming a public health problem worldwide. The colonization of Group B Streptococcus and Staphylococcus in the rectovaginal area is among the sources of infections in neonates which can result in illness and mortality. The over exposure of humans to antibiotics is the possible cause of resistance in bacteria. These resistant strains can be passed onto offspring, leading to resistant infections and increasing the morbidity of neonates because of treatment failures. Many people, including healthcare personnel are not aware of the effect of these bacteria, and informing clinics and hospitals can help create awareness and monitoring the levels of resistance among bacteria can assist in preventing the transference of the bacteria. In this study we investigated the prevalence of group B Streptococcus (GBS) and Staphylococcus aureus in the anogenital tract of pregnant women in the Eastern Cape Province, South Africa. A total of 49 isolates from 25 (30.5 percent) pregnant women colonized with GBS were isolated from vaginal and rectal swabs of 82 pregnant women at 25-37 gestation who participated in this study. These isolates were obtained using standard microbiological methods and confirmed by polymerase chain reaction (PCR) technique aimed at the ScpB gene. The isolates were further screened for the presence of 9 serogroups (Ia, Ib, II, III, IV, V, VI, VII, VII) and serogroups Ib 2 (4.8 percent), II 20 (40.8 percent) and IV 5 (10.2 percent) and 22 non-typable (44.9 percent) were identified. Susceptibility profiling of the isolates to 12 antibiotics (tetracycline, clindamycin, erythromycin, gentamycin, naladixic acid, norfloxacin, chloramphenicol, cefuroxime, cefotaxime, imipenem, penicillin and vancomycin) was tested in vitro by the standardized disc diffusion method. All the confirmed GBS isolates (49) were resistant to erythromycin, tetracycline and clindamycin. A higher percentage of the isolates were resistant to gentamycin 44 (90 percent), nalidixic acid 41 (84 percent), penicillin 41 (84 percent), chloramphenicol 38 (78 percent), cefuroxime 36 (74 percent), imipenem 36 (74 percent), cefotaxime 35 (71 percent), norfloxacin 32 (65 percent) and vancomycin 31 (78 percent). Multiple antimicrobial resistance patterns ranged from 9‒11 and indices ranged from 0.7‒0.9, respectively. Among the antimicrobial resistance determinants examined, genes encoding for resistance to erythromycin ermB 25 (51 percent), tetracycline tetM 32 (65 percent) and penicillin bla-Z 4 (8 percent) only were identified. On the other hand, screening for S. aureus yielded a total of 7 isolates from 4 study participants as confirmed by PCR based on staphylococcal, nuc gene. The isolates were further screened for the presence of six virulence genes (Hla, Hlb, LUKM, LUKED, PVL, Eta and Etb) and antibiotic susceptibility pattern by the disc diffusion method using 12 (penicillin, vancomycin, tetracycline, rifampicin, imipenem, gentamycin, chloramphenicol, norfloxacin, oxacillin, erythromycin and sulfamethoxazole-trimethoprim) antibiotics that are adopted in the treatment of infections caused by the organism. PVL 6 (85.7 percent) and eta 1 (14.3 percent) were the two virulence genes detected. The following percentages of antibiotics resistance among the isolates were observed; penicillin G 7 (100 percent), clindamycin 7 (100 percent), vancomycin 5 (100 percent), rifampicin 5 (71 percent), oxacillin 5 (71 percent), erythromycin 5 (71 percent) gentamycin 3 (43 percent), norfloxacin 3 (43 percent), sulfamethoxazole-trimethoprim 3 (43 percent), chloramphenicol 2 (29 percent), imipenem 1 (14 percent). Multiple antimicrobial resistance patterns ranged from 7‒8 and indices ranged from 0.6‒0.7, respectively. Genetic profiling of the resistance genes identified erythromycin ermB 5(71.4 percent), tetracycline tetM 5(71.4 percent) and penicillin bla-Z 1(14.3 percent) only. The findings from the study have revealed GBS and S. aureus colonization of pregnant women in the Eastern Cape Province, and these have great public health implications especially for the neonates who are mostly likely to be infected during birth. The unidentifiable multidrug resistant serogroups of GBS as well as resistant S. aureus limit the choice of drugs in the management of infections caused by these pathogens more so if transmitted to infants. Therefore asymptomatic pregnant women needed to be properly educated about the bacteria as well as the precautions that need to be taken.
- Full Text:
- Date Issued: 2017
Quality indices of the Eastern Cape beach waters in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa
- Authors: Mani, Sinalo
- Date: 2017
- Subjects: Waterfronts -- Recreational use -- South Africa -- Eastern Cape Water quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/19054 , vital:40108
- Description: Surface waters constitute important sources of water and serve for agricultural, recreational and industrial purposes; however, the vulnerability of such water sources to pollution presents serious ecological, public health and economic problems of global concerns. Beach water quality is monitored to reduce the risk of recreational waterborne illnesses. Water samples were collected between September 2014 and August 2015 at Eastern beach and a total of 5 physicochemical parameters, counts of faecal coliforms, E. coli and Enterococcus isolates were determined using standard analytical procedures. Confirmed Escherichia coli isolates were assessed for virulence genes associated with pathogenic E. coli strains responsible for intestinal and extra-intestinal infections. Recovered E. coli isolates were then interpreted for their antibiogram profiling using disk diffusion method. On the other hand, the recovered Enterococcus isolates were characterized for Enterococcus speciation of key species that are normally implicated in infections and further assessed for their antibiogram profiling by disk diffusion method. The physicochemical qualities of the water ranged as follows: turbidity (1.4 to 36.8 NTU); pH (7.0 to 8.6); temperature (14.5 to 24.5 ºC); total dissolved solids (TDS) (5.2 to 46 mg/L) and electrical conductivity (EC) (8.2 to 70.7 μS/cm). Microbiological qualities obtained were as follows: faecal coliform (101 to 103 CFU/100 mL); Escherichia coli (101 to 103 CFU/100 mL); and enterococci (101 CFU/100 mL to 102 CFU/100 mL). Only 38/104 (37 percent) harbored at least 1 virulence gene while 66/104 (63 percent) of the isolates harbored none. Most frequent virulence genes were eae for EPEC/EHEC, fliCH7 for EHEC, ibeA for NMEC, while daaE for DAEC and ipaH for EIEC were discovered in three isolates each; bfp for EPEC was detected in 2 isolates and lt gene for ETEC in one isolate. EAEC and UPEC genes were not detected in all the isolates. All tested isolates were resistant to ampicillin, tetracycline, gentamycin and chloramphenicol (85 percent), ciprofloxacin (78 percent), trimethoprim (54 percent) and norfloxacin (54 percent) and the Multiple Antibiotic Resistance Index for all isolates ranged between 0.6- 1.0 with the average being 0.8, which exceeded the threshold value of 0.2. Among the 96 recovered Enterococcus isolates, 55 percent were identified as E. faecium, 22 percent were E. hirae, 2 percent were E. durans and 21 percent were uncharacterized Enterococcus species. E. faecalis and E. casseliflavus were not detected amongst the isolates. All isolates were resistant to vancomycin, erythromycin and chloramphenicol. While the resistance against other antibiotics followed the order: tetracycline (97 percent), gentamycin (96 percent), ciprofloxacin (93 percent), linezolid (91 percent), ampicillin (91 percent) and trimethoprim (62percent). Only 6 percent of the isolates were susceptible to trimethoprim and the MAR index for all isolates ranged between 0.6- 1.0 with the average being 0.9 which greater than 0.2, suggesting that these bacterial strains originates from environments with high use or contamination of antibiotics.
- Full Text:
- Date Issued: 2017
- Authors: Mani, Sinalo
- Date: 2017
- Subjects: Waterfronts -- Recreational use -- South Africa -- Eastern Cape Water quality -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/19054 , vital:40108
- Description: Surface waters constitute important sources of water and serve for agricultural, recreational and industrial purposes; however, the vulnerability of such water sources to pollution presents serious ecological, public health and economic problems of global concerns. Beach water quality is monitored to reduce the risk of recreational waterborne illnesses. Water samples were collected between September 2014 and August 2015 at Eastern beach and a total of 5 physicochemical parameters, counts of faecal coliforms, E. coli and Enterococcus isolates were determined using standard analytical procedures. Confirmed Escherichia coli isolates were assessed for virulence genes associated with pathogenic E. coli strains responsible for intestinal and extra-intestinal infections. Recovered E. coli isolates were then interpreted for their antibiogram profiling using disk diffusion method. On the other hand, the recovered Enterococcus isolates were characterized for Enterococcus speciation of key species that are normally implicated in infections and further assessed for their antibiogram profiling by disk diffusion method. The physicochemical qualities of the water ranged as follows: turbidity (1.4 to 36.8 NTU); pH (7.0 to 8.6); temperature (14.5 to 24.5 ºC); total dissolved solids (TDS) (5.2 to 46 mg/L) and electrical conductivity (EC) (8.2 to 70.7 μS/cm). Microbiological qualities obtained were as follows: faecal coliform (101 to 103 CFU/100 mL); Escherichia coli (101 to 103 CFU/100 mL); and enterococci (101 CFU/100 mL to 102 CFU/100 mL). Only 38/104 (37 percent) harbored at least 1 virulence gene while 66/104 (63 percent) of the isolates harbored none. Most frequent virulence genes were eae for EPEC/EHEC, fliCH7 for EHEC, ibeA for NMEC, while daaE for DAEC and ipaH for EIEC were discovered in three isolates each; bfp for EPEC was detected in 2 isolates and lt gene for ETEC in one isolate. EAEC and UPEC genes were not detected in all the isolates. All tested isolates were resistant to ampicillin, tetracycline, gentamycin and chloramphenicol (85 percent), ciprofloxacin (78 percent), trimethoprim (54 percent) and norfloxacin (54 percent) and the Multiple Antibiotic Resistance Index for all isolates ranged between 0.6- 1.0 with the average being 0.8, which exceeded the threshold value of 0.2. Among the 96 recovered Enterococcus isolates, 55 percent were identified as E. faecium, 22 percent were E. hirae, 2 percent were E. durans and 21 percent were uncharacterized Enterococcus species. E. faecalis and E. casseliflavus were not detected amongst the isolates. All isolates were resistant to vancomycin, erythromycin and chloramphenicol. While the resistance against other antibiotics followed the order: tetracycline (97 percent), gentamycin (96 percent), ciprofloxacin (93 percent), linezolid (91 percent), ampicillin (91 percent) and trimethoprim (62percent). Only 6 percent of the isolates were susceptible to trimethoprim and the MAR index for all isolates ranged between 0.6- 1.0 with the average being 0.9 which greater than 0.2, suggesting that these bacterial strains originates from environments with high use or contamination of antibiotics.
- Full Text:
- Date Issued: 2017
Quality indices of the Nahoon beach and canal in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa
- Authors: Ebomah, Kingsley Ehi
- Date: 2017
- Subjects: Pathogenic bacteria -- South Africa -- Eastern Cape Water quality -- South Africa -- Eastern Cape -- Measurement Water -- Microbiology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8122 , vital:31525
- Description: Faecal indicator bacteria have long been recommended for usage in water quality monitoring of various water sources including surface water. A large number of people in different parts of the world often engage in recreational and other commercial activities at the various beaches along the coastal lines, most especially, during summer season and festive periods. It is generally assumed that beach water is safe all the times, however, there have been increasing reports of beach and other coastal water pollutions because of rising anthropogenic activities around coastal areas globally. The presence of pathogens in faecal contaminated beach water either directly or indirectly increases the risk of human exposure which may result in skin infections as well as the ingestion and transmission of multidrug resistant pathogens. Microorganisms may gain entry into beach water directly from improperly treated final effluents released by wastewater treatment plants and from agricultural runoffs and/or faulty drainages. The aim of this study was to evaluate the quality indices of the Nahoon Beach and canal waters in the Eastern Cape Province of South Africa. In order to achieve this aim, the objectives of this study were as follow: to determine the seasonal variations of the physicochemical characteristics of the Nahoon beach and canal waters, to assess the microbiological quality of the beach water by assessing the prevalence of potentially E. coli and Enterococcus species, and to evaluate the antibiogram profile of the E. coli pathotypes and Enterococci species recovered from the beach water samples. Water samples were collected bi-weekly for a period of twelve months, during which on-site physicochemical analyses were carried out. Bacteriological assessment was performed using the membrane filtration technique and the necessary incubation conditions were followed. Identification of the target organisms was done by molecular based methods using PCR (polymerase chain reaction) while antibiotic susceptibility testing was done using the disk diffusion method. During the spring season (August to October) and periods of festive activities (December, January and March), it was observed that turbidity was at its highest, consequently, influencing total dissolved solids and a rise in the values of pH and electrical conductivity. Microbiological qualities assessed follow the order: Escherichia coli (101 – 103 CFU/100ml) and Enterococcus (101 – 102 CFU/100 ml). The results show that 41.2percent (107/260) of the presumptive E. coli isolates were positive for uidA gene. A total of 73 out of 107 (68.2percent) PCR-confirmed E. coli isolates were observed to belong to different pathotypes while 59percent (102/172) of the presumptive Enterococcus strains isolated were positive for SodA gene (Enterococcus spp.). Out of 102 enterococci isolates, 45 strains were identified as species (E. faecalis and E. faecium) and these were subjected to antibiotic susceptibility testing. The E. coli strains exhibited a frequency of 100percent resistance against ampicillin while the Enterococcus strains also showed 100percent resistance against vancomycin and linezolid. Target genes eae 11 (10.3percent); ipaH 14 (13.1percent); ibeA 48 (44.9percent) that encode pathogenicity in E. coli were successfully amplified by PCR suggesting that the isolates are potentially pathogenic strains whereas Enterococcus spp. including Enterococcus faecalis 26 (25.5percent) and Enterococcus faecium 19 (18.6percent) were also identified in the water samples. In this study, the phenotypic antibiogram profiles of the E. coli isolates revealed that all 73 (100percent) of the pathotypes were resistant to ampicillin, 67 (91.8percent) were resistant to amikacin, gentamicin and ceftazidime while about 61 (83.6percent) and 51 (69.9percent) were resistant to tetracycline and ciprofloxacin as well as trimethoprim respectively. About 21.9percent (16) of the E. coli isolates exhibited multiple antibiotic resistances with 100percent being resistant to eight antibiotics whereas multiple antimicrobial resistances were observed in 14 (31percent) of the enterococci strains and the most predominant profile was the simultaneous resistance to ampicillin, penicillin and vancomycin. The results obtained in this study show that the beach water generally did not comply with the set guidelines. The results also suggest the possible survival and prevalence of potentially virulent E. coli as well as Enterococcus strains in the aquatic environment which may be a cause of concern for public health. Monitoring of the quality of surface water and antimicrobial resistance (AMR) in bacteria is of great importance and has clinical and human health significance. Nonetheless, this study underscores the need for more detailed study of other waterborne pathogens of health importance including enteric viruses to ascertain the safety of the beach for human use.
- Full Text:
- Date Issued: 2017
- Authors: Ebomah, Kingsley Ehi
- Date: 2017
- Subjects: Pathogenic bacteria -- South Africa -- Eastern Cape Water quality -- South Africa -- Eastern Cape -- Measurement Water -- Microbiology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8122 , vital:31525
- Description: Faecal indicator bacteria have long been recommended for usage in water quality monitoring of various water sources including surface water. A large number of people in different parts of the world often engage in recreational and other commercial activities at the various beaches along the coastal lines, most especially, during summer season and festive periods. It is generally assumed that beach water is safe all the times, however, there have been increasing reports of beach and other coastal water pollutions because of rising anthropogenic activities around coastal areas globally. The presence of pathogens in faecal contaminated beach water either directly or indirectly increases the risk of human exposure which may result in skin infections as well as the ingestion and transmission of multidrug resistant pathogens. Microorganisms may gain entry into beach water directly from improperly treated final effluents released by wastewater treatment plants and from agricultural runoffs and/or faulty drainages. The aim of this study was to evaluate the quality indices of the Nahoon Beach and canal waters in the Eastern Cape Province of South Africa. In order to achieve this aim, the objectives of this study were as follow: to determine the seasonal variations of the physicochemical characteristics of the Nahoon beach and canal waters, to assess the microbiological quality of the beach water by assessing the prevalence of potentially E. coli and Enterococcus species, and to evaluate the antibiogram profile of the E. coli pathotypes and Enterococci species recovered from the beach water samples. Water samples were collected bi-weekly for a period of twelve months, during which on-site physicochemical analyses were carried out. Bacteriological assessment was performed using the membrane filtration technique and the necessary incubation conditions were followed. Identification of the target organisms was done by molecular based methods using PCR (polymerase chain reaction) while antibiotic susceptibility testing was done using the disk diffusion method. During the spring season (August to October) and periods of festive activities (December, January and March), it was observed that turbidity was at its highest, consequently, influencing total dissolved solids and a rise in the values of pH and electrical conductivity. Microbiological qualities assessed follow the order: Escherichia coli (101 – 103 CFU/100ml) and Enterococcus (101 – 102 CFU/100 ml). The results show that 41.2percent (107/260) of the presumptive E. coli isolates were positive for uidA gene. A total of 73 out of 107 (68.2percent) PCR-confirmed E. coli isolates were observed to belong to different pathotypes while 59percent (102/172) of the presumptive Enterococcus strains isolated were positive for SodA gene (Enterococcus spp.). Out of 102 enterococci isolates, 45 strains were identified as species (E. faecalis and E. faecium) and these were subjected to antibiotic susceptibility testing. The E. coli strains exhibited a frequency of 100percent resistance against ampicillin while the Enterococcus strains also showed 100percent resistance against vancomycin and linezolid. Target genes eae 11 (10.3percent); ipaH 14 (13.1percent); ibeA 48 (44.9percent) that encode pathogenicity in E. coli were successfully amplified by PCR suggesting that the isolates are potentially pathogenic strains whereas Enterococcus spp. including Enterococcus faecalis 26 (25.5percent) and Enterococcus faecium 19 (18.6percent) were also identified in the water samples. In this study, the phenotypic antibiogram profiles of the E. coli isolates revealed that all 73 (100percent) of the pathotypes were resistant to ampicillin, 67 (91.8percent) were resistant to amikacin, gentamicin and ceftazidime while about 61 (83.6percent) and 51 (69.9percent) were resistant to tetracycline and ciprofloxacin as well as trimethoprim respectively. About 21.9percent (16) of the E. coli isolates exhibited multiple antibiotic resistances with 100percent being resistant to eight antibiotics whereas multiple antimicrobial resistances were observed in 14 (31percent) of the enterococci strains and the most predominant profile was the simultaneous resistance to ampicillin, penicillin and vancomycin. The results obtained in this study show that the beach water generally did not comply with the set guidelines. The results also suggest the possible survival and prevalence of potentially virulent E. coli as well as Enterococcus strains in the aquatic environment which may be a cause of concern for public health. Monitoring of the quality of surface water and antimicrobial resistance (AMR) in bacteria is of great importance and has clinical and human health significance. Nonetheless, this study underscores the need for more detailed study of other waterborne pathogens of health importance including enteric viruses to ascertain the safety of the beach for human use.
- Full Text:
- Date Issued: 2017
Screening of shark liver extracts for potential antimicrobial properties against selected pathogenic bacterial strains
- Authors: Mrwetyana, Thandolwethu
- Date: 2017
- Subjects: Fishes -- Diseases Pathogenic bacteria Antibiotics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12982 , vital:39413
- Description: The growing problem of antimicrobial resistance prevents the effective treatment of bacterial infections. Traditional antibiotics such as penicillin have been rendered ineffective against most microbial pathogens. This has led to an increased need for the development of new and improved drugs. The marine environment contains a great array of organisms with unique biological properties, but still remains one of our most underutilized biological resources. The aim of this study was to screen different shark liver extracts for antimicrobial properties. After optimizing the extraction methods, the liver extracts (oil and aminosterol) of three different shark species, namely the Dogfish (Squalus acanthias), the Catshark (Scyliorhinus capensis) and the Hammerhead (Sphyrna zygaena) shark, were screened for antimicrobial properties using the Kirby-Bauer disc diffusion method against selected bacterial pathogens (Helicobacter pylori, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus cereus), after which the MIC was determined using the modified broth micro-dilution described by Vollekova et al. (2001). The most active extract was fractionated using thin layer chromatography, and TLC-direct bioautography was used to determine the antimicrobial properties of the fractionated compounds. The Folch et al and the Shinnar et al methods yielded the highest extract volumes for oil and aminosterol consecutively, and the catshark and dogfish aminosterol extract showed greater levels of bioactivity against all selected bacterial pathogens, with S. aureus showing highest susceptibility levels to both extracts. A total of 22 compounds were observed in the developed plates with two compounds (Rf 0.53 and 0.79) showing antimicrobial activity. Certain shark liver extracts possess antimicrobial properties that have the potential to be used in the development of new antimicrobial drugs.
- Full Text:
- Date Issued: 2017
- Authors: Mrwetyana, Thandolwethu
- Date: 2017
- Subjects: Fishes -- Diseases Pathogenic bacteria Antibiotics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12982 , vital:39413
- Description: The growing problem of antimicrobial resistance prevents the effective treatment of bacterial infections. Traditional antibiotics such as penicillin have been rendered ineffective against most microbial pathogens. This has led to an increased need for the development of new and improved drugs. The marine environment contains a great array of organisms with unique biological properties, but still remains one of our most underutilized biological resources. The aim of this study was to screen different shark liver extracts for antimicrobial properties. After optimizing the extraction methods, the liver extracts (oil and aminosterol) of three different shark species, namely the Dogfish (Squalus acanthias), the Catshark (Scyliorhinus capensis) and the Hammerhead (Sphyrna zygaena) shark, were screened for antimicrobial properties using the Kirby-Bauer disc diffusion method against selected bacterial pathogens (Helicobacter pylori, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus cereus), after which the MIC was determined using the modified broth micro-dilution described by Vollekova et al. (2001). The most active extract was fractionated using thin layer chromatography, and TLC-direct bioautography was used to determine the antimicrobial properties of the fractionated compounds. The Folch et al and the Shinnar et al methods yielded the highest extract volumes for oil and aminosterol consecutively, and the catshark and dogfish aminosterol extract showed greater levels of bioactivity against all selected bacterial pathogens, with S. aureus showing highest susceptibility levels to both extracts. A total of 22 compounds were observed in the developed plates with two compounds (Rf 0.53 and 0.79) showing antimicrobial activity. Certain shark liver extracts possess antimicrobial properties that have the potential to be used in the development of new antimicrobial drugs.
- Full Text:
- Date Issued: 2017
Small-scale farmers' participation in planning and implementation of farmer support programmes in Amahlathi Local Municipality, Eastern Cape Province, South Africa
- Authors: Makunga, Phendulwa Zikhona
- Date: 2017
- Subjects: Agricultural development projects , Farms, Small -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6248 , vital:29529
- Description: The democratic government in South Africa has brought about several policies which were initiated for rural development, and one of the government’s strategies was to involve the agricultural sector. Farmer Support Programmes (FSPs) were developed to assist small-scale farmers to become commercial farmers. The study looked at the participation of small scale farmers in the planning and implementation of the FSPs in the Amahlathi Local Municipality. 108 small scale farmers were selected using a non-random purposive probability and twelve farmers’ organisations. Semi-structured questionnaires and semi-structured interviews were used as the data collection tool and method respectively. The data analysis used was a descriptive analysis and a thematic analysis. The results revealed that the farmers have a positive perception towards the support programmes being helpful in their farming needs. The positive perception was especially on the extension and advisory services, dipping and vaccination programme, and the supply and funding of inputs and assets. However, the results revealed that there was no significant difference between gender and the perception of the farmers when a chi square test of association was performed. The results also revealed that the farmers and farmers’ organisations were not involved in the planning of the programmes by the government. It is therefore recommended that for the success of the FSP and for economic growth in the rural areas, the government has to avoid using a top-down approach when developing these programmes, and instead consult the farmers and the farmers’ organisations to know the specific needs of the farmers in their farming practices.
- Full Text:
- Date Issued: 2017
- Authors: Makunga, Phendulwa Zikhona
- Date: 2017
- Subjects: Agricultural development projects , Farms, Small -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6248 , vital:29529
- Description: The democratic government in South Africa has brought about several policies which were initiated for rural development, and one of the government’s strategies was to involve the agricultural sector. Farmer Support Programmes (FSPs) were developed to assist small-scale farmers to become commercial farmers. The study looked at the participation of small scale farmers in the planning and implementation of the FSPs in the Amahlathi Local Municipality. 108 small scale farmers were selected using a non-random purposive probability and twelve farmers’ organisations. Semi-structured questionnaires and semi-structured interviews were used as the data collection tool and method respectively. The data analysis used was a descriptive analysis and a thematic analysis. The results revealed that the farmers have a positive perception towards the support programmes being helpful in their farming needs. The positive perception was especially on the extension and advisory services, dipping and vaccination programme, and the supply and funding of inputs and assets. However, the results revealed that there was no significant difference between gender and the perception of the farmers when a chi square test of association was performed. The results also revealed that the farmers and farmers’ organisations were not involved in the planning of the programmes by the government. It is therefore recommended that for the success of the FSP and for economic growth in the rural areas, the government has to avoid using a top-down approach when developing these programmes, and instead consult the farmers and the farmers’ organisations to know the specific needs of the farmers in their farming practices.
- Full Text:
- Date Issued: 2017
Socio-economic benefits of agricultural projects to surrounding communities: the case of Qamata Irrigation Scheme in the Eastern Cape, South Africa
- Authors: Masela, Zandile
- Date: 2017
- Subjects: Agricultural development projects -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4716 , vital:28501
- Description: The Qamata Irrigation Scheme (QIS) is one of the largest irrigation schemes in South Africa. Despite substantial state investment, community members have only derived limited benefits from the scheme, leading the government efforts to revitalize the scheme. Many studies have been conducted about QIS but none of them have analyzed the effects of the QIS on the surrounding communities. This study investigated the socio-economic benefits of QIS to surrounding communities. For the purposes of this study, the units of analysis were the surrounding household members, questionnaires were used to collect data. Probabilistic sampling of random sampling method was used to select the villages; respondents’ were availability selected with sample size of 197 households. Quantitative and qualitative data were collected from the participants. To analyse data, descriptive statistics and multinomial logit regression model were used. The study found out that female-headed households constitute 63.45 percent compared to male-headed households at 36.55 percent. The average age of the households in the villages that are within the radius of 10km is 58 years, while it is 59 years in villages that are beyond the 10km radius. In villages within the radius of 10km, 86.08 percent of respondents are unemployed, 5.70 percent are employed at the scheme and 8.23 percent are self-employed. In villages beyond 10km, 84.62 percent of respondents are unemployed, 5.13 percent are employed at the scheme and 10.26 percent are self-employed. In both villages, 71 percent of respondents reported that that they do not get feed supply from the scheme while 29 percent of respondents reported that they get feed supply from the scheme. From the overall distribution of villages within and beyond the radius of 10km, 80 percent of respondents reported that they do not get job opportunities from the QIS while 20 percent of respondents reported that they get job opportunities from the QIS. The study shows that 53 percent of respondents from villages within the radius of 10km are low-benefitting, 33 percent of respondents are intermediate-benefitting and 14 percent of respondents are high-benefitting from the scheme, while in villages beyond the radius of 10km, 97 percent of respondents are low-benefitting, 3 percent of respondents are intermediate-benefitting and none of the respondents is high-benefitting from the scheme. Furthermore, the study, through the multinomial logit regression model, shows that gender for intermediate benefitting has a negative coefficient (-1.70) and shows a significance of 10 percent On the other hand, gender for high benefitting has a positive coefficient (2.57) and shows a significance of 1 percent. Distance from the scheme has a negative coefficient (-3.08) and shows a significance of 1 percent. Access to farmland has a positive coefficient (2.33) and shows a significance of 10 percent. The study recommends that surrounding communities should own home gardens so that they can grow fresh produce and create job opportunities. The surrounding communities are also encouraged to own more farmlands or produce their own crops so they can also learn from the skills of the scheme.
- Full Text:
- Date Issued: 2017
- Authors: Masela, Zandile
- Date: 2017
- Subjects: Agricultural development projects -- South Africa -- Eastern Cape , Agriculture -- Economic aspects -- South Africa -- Eastern Cape , Irrigation farming -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4716 , vital:28501
- Description: The Qamata Irrigation Scheme (QIS) is one of the largest irrigation schemes in South Africa. Despite substantial state investment, community members have only derived limited benefits from the scheme, leading the government efforts to revitalize the scheme. Many studies have been conducted about QIS but none of them have analyzed the effects of the QIS on the surrounding communities. This study investigated the socio-economic benefits of QIS to surrounding communities. For the purposes of this study, the units of analysis were the surrounding household members, questionnaires were used to collect data. Probabilistic sampling of random sampling method was used to select the villages; respondents’ were availability selected with sample size of 197 households. Quantitative and qualitative data were collected from the participants. To analyse data, descriptive statistics and multinomial logit regression model were used. The study found out that female-headed households constitute 63.45 percent compared to male-headed households at 36.55 percent. The average age of the households in the villages that are within the radius of 10km is 58 years, while it is 59 years in villages that are beyond the 10km radius. In villages within the radius of 10km, 86.08 percent of respondents are unemployed, 5.70 percent are employed at the scheme and 8.23 percent are self-employed. In villages beyond 10km, 84.62 percent of respondents are unemployed, 5.13 percent are employed at the scheme and 10.26 percent are self-employed. In both villages, 71 percent of respondents reported that that they do not get feed supply from the scheme while 29 percent of respondents reported that they get feed supply from the scheme. From the overall distribution of villages within and beyond the radius of 10km, 80 percent of respondents reported that they do not get job opportunities from the QIS while 20 percent of respondents reported that they get job opportunities from the QIS. The study shows that 53 percent of respondents from villages within the radius of 10km are low-benefitting, 33 percent of respondents are intermediate-benefitting and 14 percent of respondents are high-benefitting from the scheme, while in villages beyond the radius of 10km, 97 percent of respondents are low-benefitting, 3 percent of respondents are intermediate-benefitting and none of the respondents is high-benefitting from the scheme. Furthermore, the study, through the multinomial logit regression model, shows that gender for intermediate benefitting has a negative coefficient (-1.70) and shows a significance of 10 percent On the other hand, gender for high benefitting has a positive coefficient (2.57) and shows a significance of 1 percent. Distance from the scheme has a negative coefficient (-3.08) and shows a significance of 1 percent. Access to farmland has a positive coefficient (2.33) and shows a significance of 10 percent. The study recommends that surrounding communities should own home gardens so that they can grow fresh produce and create job opportunities. The surrounding communities are also encouraged to own more farmlands or produce their own crops so they can also learn from the skills of the scheme.
- Full Text:
- Date Issued: 2017
Species composition and seasonal population dynamics of free-living and engorged cattle ticks in three agro-ecological zones of the Eastern Cape Province, South Africa
- Authors: Yawa, Mandla
- Date: 2017
- Subjects: Ticks Boophilus microplus
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9067 , vital:34224
- Description: This study was conducted to determine species composition and seasonal population dynamics of free-living and engorged cattle ticks in three agro-ecological zones (Bedford dry grassland, Kowie thicket and Bisho thornveld) of the Eastern Cape Province, South Africa. The occurrence of ticks on cattle was studied monthly from April 2016 and March 2017. Tick collections were performed on 360 selected cattle in each agro-ecological zones. During tick collections, 10 randomly selected cattle were sampled at each locality and more attention was given to African blue tick and the presence of Asian blue tick. A half body tick collection was performed from cattle and visible ticks were collected by means of fine-forceps after the animals had been restrained. Body regions that were examined includes the ear, head, neck, chest, abdomen, flank, front and hind leg and feet, tail, and peri-anal region. At each locality, six replicate drags of 100 m, approximately 50 m apart, were performed to collect ticks from vegetation. All ticks collected per cattle and from vegetation were stored in labelled sample tubes containing 70percent ethanol, subsequently counted and identified to genus and species level using a standard stereomicroscope. A total of 31425 ticks belonging to ten species were collected during the study. Rhipicephalus (Boophilus) decoloratus, was the most observed tick species (32.50percent), all other ticks like R. evertsi evertsi (18.84percent), R. appendiculatus (17.26percent), A. hebraeum (16.27percent), R. simus (7.69percent) were also commonly collected. Ixodes pilosus (3.84percent), H. rufipes (3.46percent), R. follis (0.08percent) together with Haemaphysalis silacea (0.02percent) were sporadic infestation. Haemaphysalis elliptica (0.04percent) was only found on the vegetation. No H. rufipes was collected in the thicket vegetation. Agro-ecological zones differ significantly (P<0.05) in tick species and distribution. Significantly more R. (B.) decoloratus were collected in thicket during summer compared to thornveld and dry grassland regions (P<0.05). Free-living ticks were widely distributed across different seasons but with of R. (B.) decoloratus larvae were significantly higher (P<0.05) in thornveld region during the spring season. In conclusion, agro-ecological differences and seasonal variations had an influence on ticks abundance and distribution. From this study, it is of interest to note the absence of R. (B.) microplus, whose trend to invade new areas previously colonised by R. (B.) decoloratus has been observed in Africa. In conclusion, agro-ecological differences and seasonal variations had an influence on ticks abundance and distribution. The aforementioned absence of R. (B.) microplus in this study highlights the importance of further research as this tick invades new areas previously colonised by R. (B.) decoloratus in the continent.
- Full Text:
- Date Issued: 2017
- Authors: Yawa, Mandla
- Date: 2017
- Subjects: Ticks Boophilus microplus
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9067 , vital:34224
- Description: This study was conducted to determine species composition and seasonal population dynamics of free-living and engorged cattle ticks in three agro-ecological zones (Bedford dry grassland, Kowie thicket and Bisho thornveld) of the Eastern Cape Province, South Africa. The occurrence of ticks on cattle was studied monthly from April 2016 and March 2017. Tick collections were performed on 360 selected cattle in each agro-ecological zones. During tick collections, 10 randomly selected cattle were sampled at each locality and more attention was given to African blue tick and the presence of Asian blue tick. A half body tick collection was performed from cattle and visible ticks were collected by means of fine-forceps after the animals had been restrained. Body regions that were examined includes the ear, head, neck, chest, abdomen, flank, front and hind leg and feet, tail, and peri-anal region. At each locality, six replicate drags of 100 m, approximately 50 m apart, were performed to collect ticks from vegetation. All ticks collected per cattle and from vegetation were stored in labelled sample tubes containing 70percent ethanol, subsequently counted and identified to genus and species level using a standard stereomicroscope. A total of 31425 ticks belonging to ten species were collected during the study. Rhipicephalus (Boophilus) decoloratus, was the most observed tick species (32.50percent), all other ticks like R. evertsi evertsi (18.84percent), R. appendiculatus (17.26percent), A. hebraeum (16.27percent), R. simus (7.69percent) were also commonly collected. Ixodes pilosus (3.84percent), H. rufipes (3.46percent), R. follis (0.08percent) together with Haemaphysalis silacea (0.02percent) were sporadic infestation. Haemaphysalis elliptica (0.04percent) was only found on the vegetation. No H. rufipes was collected in the thicket vegetation. Agro-ecological zones differ significantly (P<0.05) in tick species and distribution. Significantly more R. (B.) decoloratus were collected in thicket during summer compared to thornveld and dry grassland regions (P<0.05). Free-living ticks were widely distributed across different seasons but with of R. (B.) decoloratus larvae were significantly higher (P<0.05) in thornveld region during the spring season. In conclusion, agro-ecological differences and seasonal variations had an influence on ticks abundance and distribution. From this study, it is of interest to note the absence of R. (B.) microplus, whose trend to invade new areas previously colonised by R. (B.) decoloratus has been observed in Africa. In conclusion, agro-ecological differences and seasonal variations had an influence on ticks abundance and distribution. The aforementioned absence of R. (B.) microplus in this study highlights the importance of further research as this tick invades new areas previously colonised by R. (B.) decoloratus in the continent.
- Full Text:
- Date Issued: 2017
Stem cutting propagation protocol for rose-scented geranium (Pelargonium graveolens)
- Authors: Matafeni, Ntombekhaya
- Date: 2017
- Subjects: Plant propagation Pelargoniums Plant cuttings
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9832 , vital:35060
- Description: Rose-scented geranium (Pelargonium graveolens), is a high value essential oil plant that is used in the perfumery, cosmetic, aromatherapy and food flavouring industries. The increasing demand for this plant, due to its economic importance necessitates the development of an efficient propagation protocol for quality seedling and its maximum production. The present study therefore, sought to develop effective stem cutting propagation protocol which could facilitate multiplication of rose-scented geranium stem cuttings. Three separate experiments were undertaken to determine factors influencing effective propagation of rose-scented geranium. These factors were: rooting media, rooting hormone, cutting length and wound healing period on rooting and development of rose-scented geranium stem cuttings. The cuttings were assessed based on root number, length and fresh mass, plant height, leaf number, and stem circumference. In terms of root measurements, the growing media were washed out from the root system of plantlets, their roots were separated from stem before data was recorded which comprised of root number, length and root fresh mass. Root holding ability (RHA) on rooting medium was determined by visual observation and rated on a 1-5 scale where 1 = very loose, not acceptable; 2 = loose, not acceptable; 3 = medium, marginally acceptable; 4 = tight, acceptable; 5 = very tight, acceptable. The experiments were carried out at Essential Amatole Nursery, at the University of Fort Hare Research Farm, Alice Campus (located at 320 47ʹ3ʺS, 260 50ʹ43ʺ E, with an altitude of 519 m.a.s.l). All the experiments were carried out under mist conditions on bottom-heated beds in a greenhouse (with polycarbonate roofing of about 40percent shading effect) for the first three weeks after sticking the cuttings to the growing medium to facilitate root induction in relatively high temperature and relative humidity. Thereafter, the plantlets were grown in a shade house with 70percent light penetration until the termination of the experiment. To optimize the technology for the propagation of this plant the present experiment was designed with the objective to determine the efficient growing medium and proper rooting hormone for successful rooting and development of quality seedlings of rose-scented geranium. The experiment was set up in a complete randomized design (CRD) and was replicated three times with two factors 7×4, seven different growing media i.e. (1) Mixture growing medium which serves as control (pine bark 8 bags + sand 2 bags + lime 4kg + coconut 10 blocks + talborne 6.25 kg + bone meal 2 kg); (2) River sand only; (3) Pine bark; (4) Hygrotex (commercial rooting media); (5) Pine bark + river sand ( at1:1 ratio on volume basis); (6) Pine bark + hygrotex (at 1:1, ratio on volume basis), and; (7) Pine bark + river sand + hygrotex ( at 1:1:1 ratio on volume basis) and four different IBA hormone levels (auxins, types of IBA) applied as treatment were (1) Dynaroot (1 – 1g/kg), (2) Dynaroot (2- 3g/kg), (3) Dynaroot (3-8g/kg) and (4) Control (untreated with hormone). Hygrotex was identified as the best growth media for quicker regeneration giving the highest root number, length and fresh mass. While, hygrotex + pine bark (v/v 1:1) was efficient in producing more leaves, stem circumference and other aerial parameters. Dynaroot 3 was identified as the best rooting enhancer with maximum root number, length, fresh weight and plant height. Both Dynaroot 3 and Dynaroot 2 did not have major differences on giving highest leaf number. Control (untreated with hormone) was consistent in giving the greatest stem circumference than any other treatment. To maximize stem circumference, a combination of control (untreated with hormone) and hygrotex + pine bark (v/v 1:1) was identified as the best treatment. Based on the investigation for maximum production and quality seedlings of rose-scented geranium, hygrotex and Dynaroot 3 were identified as the best combination for successful rooting. The ideal cutting stem length, rooting hormone and growing medium for quality seedlings of rose-scented geranium were also investigated. The experimental lay out was in randomized complete design (RCD) with a 4 × 4 × 2 factorial treatment combination. Treatments used were, four different cutting lengths viz. 10, 12, 14 and 16 cm long; four different concentrations of IBA rooting hormone (Dynaroot 1, 2, 3 (powder form) and distilled water (control) and two types of growing medium (hygrotex and hygrotex + pine bark v/v 1:1) were used. Stem cuttings of 14 and 16 cm length gave the highest root number of 34, 38 and 35.13, and root length of 3.40 and 3.51cm respectively, with no significance. Cutting length of 10 cm favoured stem circumference (3.1 cm) as compared to other treatments. Whereas, cuttings treated with Dynaroot 3 showed a better root number (33.46 roots), root length (3.54 cm), root fresh mass (0.59 mg), leaf number of (11.08) as well as highest root holding ability (5). However, they showed no significance difference with Dynaroot 2 treated cuttings. In addition, cuttings treated with Control favoured shoot number (3.79) and stem circumference (3.05). Visually, hygrotex was observed to be better substrate though it was not significantly different from hygrotex + pine bark (1:1 v/v) on propagation of rose-scented geranium stem cuttings. Therefore, it is recommended that rose-scented geranium should be propagated through the combination of 14 cm cuttings length and treated with Dynaroot 2 IBA rooting hormone. Both hygrotex and hygrotex + pine bark (1:1 v/v) are the best growing media for root formation and growth of rose-scented geranium, though hygrotex alone is more economical. Wound healing period (WHP) of stem cutting was evaluated using 4 × 4 factorial, cuttings were separated into four groups during the healing duration (intervals of 24 hrs: days 0, 1, 2 and 3). These four groups were further subdivided into four subgroups of rooting hormone viz. Dynaroot 1, 2, 3 of indole-3-butyric acid and control (water). Experiment was laid out in a randomised complete block design (RCBD) with three replicates. The results obtained from the study revealed that rose-scented geranium rooted easily when planted on Day 2 of the wound healing period such that root holding ability was at its highest. While, Day 0 cuttings showed good response for stem circumference and shoot number. The study recommends that rose-scented geranium be propagated using cuttings that have enough time to heal the wound that is, Day 2 cuttings. Dynaroot 3 (IBA hormone concentration) showed good response to rooting and other arial parameters except for stem circumference which was favoured by application of control. Based on the results of the study, it can be concluded that propagation of rose-scented geranium requires a wound healing period of about three days in room temperature and application of IBA hormone before sucking cuttings in growing medium. Instead, of Dynaroot 3 or 2, Dynaroot 1 can also be used because, it is less economical and they all have a similar effect on cuttings that have been healing for three days.
- Full Text:
- Date Issued: 2017
- Authors: Matafeni, Ntombekhaya
- Date: 2017
- Subjects: Plant propagation Pelargoniums Plant cuttings
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9832 , vital:35060
- Description: Rose-scented geranium (Pelargonium graveolens), is a high value essential oil plant that is used in the perfumery, cosmetic, aromatherapy and food flavouring industries. The increasing demand for this plant, due to its economic importance necessitates the development of an efficient propagation protocol for quality seedling and its maximum production. The present study therefore, sought to develop effective stem cutting propagation protocol which could facilitate multiplication of rose-scented geranium stem cuttings. Three separate experiments were undertaken to determine factors influencing effective propagation of rose-scented geranium. These factors were: rooting media, rooting hormone, cutting length and wound healing period on rooting and development of rose-scented geranium stem cuttings. The cuttings were assessed based on root number, length and fresh mass, plant height, leaf number, and stem circumference. In terms of root measurements, the growing media were washed out from the root system of plantlets, their roots were separated from stem before data was recorded which comprised of root number, length and root fresh mass. Root holding ability (RHA) on rooting medium was determined by visual observation and rated on a 1-5 scale where 1 = very loose, not acceptable; 2 = loose, not acceptable; 3 = medium, marginally acceptable; 4 = tight, acceptable; 5 = very tight, acceptable. The experiments were carried out at Essential Amatole Nursery, at the University of Fort Hare Research Farm, Alice Campus (located at 320 47ʹ3ʺS, 260 50ʹ43ʺ E, with an altitude of 519 m.a.s.l). All the experiments were carried out under mist conditions on bottom-heated beds in a greenhouse (with polycarbonate roofing of about 40percent shading effect) for the first three weeks after sticking the cuttings to the growing medium to facilitate root induction in relatively high temperature and relative humidity. Thereafter, the plantlets were grown in a shade house with 70percent light penetration until the termination of the experiment. To optimize the technology for the propagation of this plant the present experiment was designed with the objective to determine the efficient growing medium and proper rooting hormone for successful rooting and development of quality seedlings of rose-scented geranium. The experiment was set up in a complete randomized design (CRD) and was replicated three times with two factors 7×4, seven different growing media i.e. (1) Mixture growing medium which serves as control (pine bark 8 bags + sand 2 bags + lime 4kg + coconut 10 blocks + talborne 6.25 kg + bone meal 2 kg); (2) River sand only; (3) Pine bark; (4) Hygrotex (commercial rooting media); (5) Pine bark + river sand ( at1:1 ratio on volume basis); (6) Pine bark + hygrotex (at 1:1, ratio on volume basis), and; (7) Pine bark + river sand + hygrotex ( at 1:1:1 ratio on volume basis) and four different IBA hormone levels (auxins, types of IBA) applied as treatment were (1) Dynaroot (1 – 1g/kg), (2) Dynaroot (2- 3g/kg), (3) Dynaroot (3-8g/kg) and (4) Control (untreated with hormone). Hygrotex was identified as the best growth media for quicker regeneration giving the highest root number, length and fresh mass. While, hygrotex + pine bark (v/v 1:1) was efficient in producing more leaves, stem circumference and other aerial parameters. Dynaroot 3 was identified as the best rooting enhancer with maximum root number, length, fresh weight and plant height. Both Dynaroot 3 and Dynaroot 2 did not have major differences on giving highest leaf number. Control (untreated with hormone) was consistent in giving the greatest stem circumference than any other treatment. To maximize stem circumference, a combination of control (untreated with hormone) and hygrotex + pine bark (v/v 1:1) was identified as the best treatment. Based on the investigation for maximum production and quality seedlings of rose-scented geranium, hygrotex and Dynaroot 3 were identified as the best combination for successful rooting. The ideal cutting stem length, rooting hormone and growing medium for quality seedlings of rose-scented geranium were also investigated. The experimental lay out was in randomized complete design (RCD) with a 4 × 4 × 2 factorial treatment combination. Treatments used were, four different cutting lengths viz. 10, 12, 14 and 16 cm long; four different concentrations of IBA rooting hormone (Dynaroot 1, 2, 3 (powder form) and distilled water (control) and two types of growing medium (hygrotex and hygrotex + pine bark v/v 1:1) were used. Stem cuttings of 14 and 16 cm length gave the highest root number of 34, 38 and 35.13, and root length of 3.40 and 3.51cm respectively, with no significance. Cutting length of 10 cm favoured stem circumference (3.1 cm) as compared to other treatments. Whereas, cuttings treated with Dynaroot 3 showed a better root number (33.46 roots), root length (3.54 cm), root fresh mass (0.59 mg), leaf number of (11.08) as well as highest root holding ability (5). However, they showed no significance difference with Dynaroot 2 treated cuttings. In addition, cuttings treated with Control favoured shoot number (3.79) and stem circumference (3.05). Visually, hygrotex was observed to be better substrate though it was not significantly different from hygrotex + pine bark (1:1 v/v) on propagation of rose-scented geranium stem cuttings. Therefore, it is recommended that rose-scented geranium should be propagated through the combination of 14 cm cuttings length and treated with Dynaroot 2 IBA rooting hormone. Both hygrotex and hygrotex + pine bark (1:1 v/v) are the best growing media for root formation and growth of rose-scented geranium, though hygrotex alone is more economical. Wound healing period (WHP) of stem cutting was evaluated using 4 × 4 factorial, cuttings were separated into four groups during the healing duration (intervals of 24 hrs: days 0, 1, 2 and 3). These four groups were further subdivided into four subgroups of rooting hormone viz. Dynaroot 1, 2, 3 of indole-3-butyric acid and control (water). Experiment was laid out in a randomised complete block design (RCBD) with three replicates. The results obtained from the study revealed that rose-scented geranium rooted easily when planted on Day 2 of the wound healing period such that root holding ability was at its highest. While, Day 0 cuttings showed good response for stem circumference and shoot number. The study recommends that rose-scented geranium be propagated using cuttings that have enough time to heal the wound that is, Day 2 cuttings. Dynaroot 3 (IBA hormone concentration) showed good response to rooting and other arial parameters except for stem circumference which was favoured by application of control. Based on the results of the study, it can be concluded that propagation of rose-scented geranium requires a wound healing period of about three days in room temperature and application of IBA hormone before sucking cuttings in growing medium. Instead, of Dynaroot 3 or 2, Dynaroot 1 can also be used because, it is less economical and they all have a similar effect on cuttings that have been healing for three days.
- Full Text:
- Date Issued: 2017
Synthesis and characterization of CdSe quantum dots for solar cell application
- Authors: Makinana, Sinovuyo
- Date: 2017
- Subjects: Quantum dots Quantum dots -- Optical properties Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5994 , vital:29466
- Description: This study shows a detailed report on the morphological, structural and optical properties of CdSe QDs synthesised by the hot injection method. Cadmium acetate dihydrate and Se powder were used as cadmium and selenide precursors, respectively. Various QD sizes were achieved by synthesizing in temperature range of 150ºC, 175ºC, 200ºC, 225ºC, 250ºC, 275ºC and 300ºC, respectively. The as synthesized QDs by the hot injection method were cross-examined for their morphological, structural and optical using HRTEM, FTIR, XRD, RS, and UV-Vis spectroscopy techniques respectively. FTIR analysis has revealed vibrations at 738, 738, 738, 738, 735, 735 and 733 cm-1 for the QDs synthesized at various temperatures of 150, 175, 200, 225, 250, 275, and 300℃, respectively. The presence of the above mentioned peaks confirms the presence of Cd-Se bond in our samples. XRD analysis of CdSe QDs revealed diffraction peaks at 2 angles of 16.66 , 25.20 , 34.77 , 40.9 , 45.39 and 49.1 for 150 17.4 , 25.22 , 34.85 , 41.7 , 44.45 and 47.5 for the QDs synthesized at various temperatures of 175 17.07 , 25.19 , 34.85 , 41.34 , 44.41 and 48.86 for 200 ; 16.34 , 25.20 , 34.76 , 40.6 , 44.74 and 49.48 for 225 ; 17.44 , 25.17 , 34.19 , 41.7 , 44.45 , 49.24 for 250 ; 16.70 , 25.16 , 34.85 , 40.32 , 45.1 and 49.1 7 for 275 ;and 17.35 , 25.18 , 35.13 , 41.63 , 45.7 , 49.48 for 300 . These XRD peaks relate to crystal planes of (100), (002), (102), (220), (103) and (112) which belong to hexagonal Wurtzite CdSe crystal structure. Additionally XRD analysis has revealed a general peak shift to higher 2 values was observed for CdSe QDs. HRTEM analysis showed that the synthesised CdSe QDs have a spherical shape and are monodispersed. Moreover, HRTEM analysis has revealed CdSe QDs modal crystallite size of 1.79 nm, 1.81 nm, 2.06 nm, 2.08 nm, 2.11 nm, 3.10 nm and 3.12 nm for the QDs synthesized at various temperatures of 150ºC, 175ºC, 200ºC, 225ºC, 250ºC, 275ºC and 300ºC, respectively. HRTEM results were in mutual agreement with XRD results. Additionally, the SAED images showed intense electron diffraction rings, which confirmed that the as-synthesised CdSe QDs have a Wurtzite crystal structure. RS analysis showed that CdSe QDs have LO and 2LO vibrational modes which are characteristic peaks for CdSe. The presence of these peaks in Raman spectra further supports our previous observation from XRD analysis and HRTEM analysis that the synthesized CdSe QDs have a Wurtzite crystal structure. The effect of synthesis temperature Raman peak shift, FHWH and peak intensity has been cross examined in this work, Moreover, the effect of increasing temperature on the peak shift, FWHM and peak intensity is discussed in detail below. UV-Vis analysis revealed an absorbance of CdSe QDs in higher wavelengths as temperature was increased. Furthermore, the Yu et al 2003 relation was used to calculate QD size and band gap energy of CdSe QDs. The results showed that QD size increases with increasing synthesis temperature, which is in agreement with HRTEM and XRD results.
- Full Text:
- Date Issued: 2017
- Authors: Makinana, Sinovuyo
- Date: 2017
- Subjects: Quantum dots Quantum dots -- Optical properties Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5994 , vital:29466
- Description: This study shows a detailed report on the morphological, structural and optical properties of CdSe QDs synthesised by the hot injection method. Cadmium acetate dihydrate and Se powder were used as cadmium and selenide precursors, respectively. Various QD sizes were achieved by synthesizing in temperature range of 150ºC, 175ºC, 200ºC, 225ºC, 250ºC, 275ºC and 300ºC, respectively. The as synthesized QDs by the hot injection method were cross-examined for their morphological, structural and optical using HRTEM, FTIR, XRD, RS, and UV-Vis spectroscopy techniques respectively. FTIR analysis has revealed vibrations at 738, 738, 738, 738, 735, 735 and 733 cm-1 for the QDs synthesized at various temperatures of 150, 175, 200, 225, 250, 275, and 300℃, respectively. The presence of the above mentioned peaks confirms the presence of Cd-Se bond in our samples. XRD analysis of CdSe QDs revealed diffraction peaks at 2 angles of 16.66 , 25.20 , 34.77 , 40.9 , 45.39 and 49.1 for 150 17.4 , 25.22 , 34.85 , 41.7 , 44.45 and 47.5 for the QDs synthesized at various temperatures of 175 17.07 , 25.19 , 34.85 , 41.34 , 44.41 and 48.86 for 200 ; 16.34 , 25.20 , 34.76 , 40.6 , 44.74 and 49.48 for 225 ; 17.44 , 25.17 , 34.19 , 41.7 , 44.45 , 49.24 for 250 ; 16.70 , 25.16 , 34.85 , 40.32 , 45.1 and 49.1 7 for 275 ;and 17.35 , 25.18 , 35.13 , 41.63 , 45.7 , 49.48 for 300 . These XRD peaks relate to crystal planes of (100), (002), (102), (220), (103) and (112) which belong to hexagonal Wurtzite CdSe crystal structure. Additionally XRD analysis has revealed a general peak shift to higher 2 values was observed for CdSe QDs. HRTEM analysis showed that the synthesised CdSe QDs have a spherical shape and are monodispersed. Moreover, HRTEM analysis has revealed CdSe QDs modal crystallite size of 1.79 nm, 1.81 nm, 2.06 nm, 2.08 nm, 2.11 nm, 3.10 nm and 3.12 nm for the QDs synthesized at various temperatures of 150ºC, 175ºC, 200ºC, 225ºC, 250ºC, 275ºC and 300ºC, respectively. HRTEM results were in mutual agreement with XRD results. Additionally, the SAED images showed intense electron diffraction rings, which confirmed that the as-synthesised CdSe QDs have a Wurtzite crystal structure. RS analysis showed that CdSe QDs have LO and 2LO vibrational modes which are characteristic peaks for CdSe. The presence of these peaks in Raman spectra further supports our previous observation from XRD analysis and HRTEM analysis that the synthesized CdSe QDs have a Wurtzite crystal structure. The effect of synthesis temperature Raman peak shift, FHWH and peak intensity has been cross examined in this work, Moreover, the effect of increasing temperature on the peak shift, FWHM and peak intensity is discussed in detail below. UV-Vis analysis revealed an absorbance of CdSe QDs in higher wavelengths as temperature was increased. Furthermore, the Yu et al 2003 relation was used to calculate QD size and band gap energy of CdSe QDs. The results showed that QD size increases with increasing synthesis temperature, which is in agreement with HRTEM and XRD results.
- Full Text:
- Date Issued: 2017
Synthesis of modified zinc oxide nanoparticles using pneumatic spray pyrolysis for solar cell application
- Authors: Ntozakhe, Luyolo
- Date: 2017
- Subjects: Zinc oxide -- Synthesis Nanoparticles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5862 , vital:29408
- Description: In this work, the pneumatic spray pyrolysis was used to synthesize un-doped and carbon doped zinc oxide (ZnO) nanoparticles. The zinc acetate, tetrabutylammonium bromide and ethanol were used as starting materials for the desired ZnO nanoparticles and the prepared samples were annealed at 400 oC in the furnace. The as synthesized un-doped and carbon doped ZnO NPs were evaluated using X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy dispersive x-ray spectroscopy (EDX), High-resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS) and Ultraviolet-visible spectroscopy (UV-Vis). XRD analysis of the synthesized NPs revealed peaks at 31.90°, 34.50°, 36.34°, 47.73°, 56.88°, 63.04°, 68.20°, and 77.33° belonging to the hexagonal Wurtzite ZnO crystal structure. The incorporation of C species into ZnO lattice was cross examined by monitoring the peak positions of the (100), (002) and (001) planes. These three main peaks of C-ZnO NPs show a peak shift to higher 2θ values which indicates substitutional carbon doping in ZnO NPs. SEM analysis has revealed that the as synthesized NPs have spherical shape and the morphology of the NPs change as the concentration of carbon increases. The EDX spectra of both un-doped and doped ZnO nanoparticles have revealed prominent peaks at 0.51 keV, 1.01 keV, 1.49 keV, 8.87 keV and 9.86 keV. Peaks at, X-ray energies of 0.51 keV and 1.01 keV respectively represent the emissions from the K-shell of oxygen and L-shell of zinc. The L-shell emission at 1.01 keV is considered as convolution of Zn 2p3/2 and Zn 2p1/2 photoelectron energies. The occurrence of these peaks in the EDX endorses the existence of Zn and O atoms in the PSP prepared samples. HRTEM analysis has revealed NPs size modal range from 6.65-14.21 nm for the PSP synthesized samples which is in mutual agreement with the XRD data calculated values. More over the selected area diffraction images displaying the fact that only the diffraction planes of (101), (002) and (100) are responsible for the diffraction pattern belonging to Wurtzite ZnO. RS analysis has revealed that the un-doped ZnO and doped ZnO samples have characteristic Raman vibration modes at 325 cm-1, and 434 cm-1 belonging to Wurtzite ZnO structure. Moreover, the prominent peak at 434 cm-1 which is the characteristic peak of E2(2) (high) mode of the Wurtzite ZnO and the E2(2) (high) has been red shifted by 4 cm-1, as compared to that found in the bulk ZnO. Additionally, the effect of carbon doping through Raman spectroscopy peak shifts of the E2(2) (high) mode, A1(LO) mode and multi-phonon has also been considered and discussed in detail. UV-Vis diffuse reflectance spectroscopy has revealed a red shift of the absorption edge with increase in C doping. Finally, the effect of nano-crystallite size and gradual prominence of C into ZnO lattice due to increase in C doping concentration in the PSP prepared nanoparticles was meticulously elaborated through Raman Spectroscopy analysis.
- Full Text:
- Date Issued: 2017
- Authors: Ntozakhe, Luyolo
- Date: 2017
- Subjects: Zinc oxide -- Synthesis Nanoparticles
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5862 , vital:29408
- Description: In this work, the pneumatic spray pyrolysis was used to synthesize un-doped and carbon doped zinc oxide (ZnO) nanoparticles. The zinc acetate, tetrabutylammonium bromide and ethanol were used as starting materials for the desired ZnO nanoparticles and the prepared samples were annealed at 400 oC in the furnace. The as synthesized un-doped and carbon doped ZnO NPs were evaluated using X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy dispersive x-ray spectroscopy (EDX), High-resolution transmission electron microscopy (HRTEM), Raman spectroscopy (RS) and Ultraviolet-visible spectroscopy (UV-Vis). XRD analysis of the synthesized NPs revealed peaks at 31.90°, 34.50°, 36.34°, 47.73°, 56.88°, 63.04°, 68.20°, and 77.33° belonging to the hexagonal Wurtzite ZnO crystal structure. The incorporation of C species into ZnO lattice was cross examined by monitoring the peak positions of the (100), (002) and (001) planes. These three main peaks of C-ZnO NPs show a peak shift to higher 2θ values which indicates substitutional carbon doping in ZnO NPs. SEM analysis has revealed that the as synthesized NPs have spherical shape and the morphology of the NPs change as the concentration of carbon increases. The EDX spectra of both un-doped and doped ZnO nanoparticles have revealed prominent peaks at 0.51 keV, 1.01 keV, 1.49 keV, 8.87 keV and 9.86 keV. Peaks at, X-ray energies of 0.51 keV and 1.01 keV respectively represent the emissions from the K-shell of oxygen and L-shell of zinc. The L-shell emission at 1.01 keV is considered as convolution of Zn 2p3/2 and Zn 2p1/2 photoelectron energies. The occurrence of these peaks in the EDX endorses the existence of Zn and O atoms in the PSP prepared samples. HRTEM analysis has revealed NPs size modal range from 6.65-14.21 nm for the PSP synthesized samples which is in mutual agreement with the XRD data calculated values. More over the selected area diffraction images displaying the fact that only the diffraction planes of (101), (002) and (100) are responsible for the diffraction pattern belonging to Wurtzite ZnO. RS analysis has revealed that the un-doped ZnO and doped ZnO samples have characteristic Raman vibration modes at 325 cm-1, and 434 cm-1 belonging to Wurtzite ZnO structure. Moreover, the prominent peak at 434 cm-1 which is the characteristic peak of E2(2) (high) mode of the Wurtzite ZnO and the E2(2) (high) has been red shifted by 4 cm-1, as compared to that found in the bulk ZnO. Additionally, the effect of carbon doping through Raman spectroscopy peak shifts of the E2(2) (high) mode, A1(LO) mode and multi-phonon has also been considered and discussed in detail. UV-Vis diffuse reflectance spectroscopy has revealed a red shift of the absorption edge with increase in C doping. Finally, the effect of nano-crystallite size and gradual prominence of C into ZnO lattice due to increase in C doping concentration in the PSP prepared nanoparticles was meticulously elaborated through Raman Spectroscopy analysis.
- Full Text:
- Date Issued: 2017
Template-assisted sol-gel synthesis of carbon doped titanium dioxide nanotubes and their characterization
- Authors: Takata, Nwabisa
- Date: 2017
- Subjects: Nanotechnology Titanium dioxide Nanostructures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13194 , vital:39473
- Description: This study reveals the effects of doping on the morphological, structural and optical properties of titanium dioxide (TiO2) nanotubes (TNTs), synthesized by sol-gel template-assisted sol-gel technique. The nanotubes (TNTs) were prepared in anodic alumina membranes (AAM) with a pore diameter range of 110-210 nm by using titanium tetra butoxide as a sol-gel precursor and oxalic acid dihydrate as a dopant source. The synthesized nanotubes were evaluated using scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), confocal Raman spectroscopy (CRS) and photoluminescence spectroscopy (PL). SEM analysis has revealed the presence of closely-packed TNTs, with a modal external tube diameters of 150, 170, 210,190 and 210 nm for the un-doped TNTs, 9 mM carbon doped-TNTs (C-TNTs), 27 mM C-TNTs, 45 mM C-TNTs and 75 mM C-TNTs respectively. The diameters are consistent with the AAM diameter range. EDX spectra revealed the presence of Ti peaks at 0.45 and 4.9 keV corresponding to Kα1 and Kβ1 emission lines respectively. Oxygen exhibits a signal at 0.5 keV corresponding to Kα1 emission line. The occurrence of these peaks in the EDX spectra endorses the existence of Ti and O atoms in the prepared titanium dioxide nanotubes. FTIR spectroscopy has revealed the presence of vibration modes at 580-660 cm-1 indicating the presence of Ti-O bonds and additional vibration modes at 2324 cm-1 resulting from C-O stretching in the C-TNTs. The XRD analysis has revealed the presence of a mixed anatase-brookite phase with diffraction peaks at 2θ angles of 25.49⁰, 38.11⁰, 40.60º, 48.14⁰, 54.58⁰, 63.00⁰, 70.11⁰ and 75.66⁰. Additionally, XRD analysis has revealed elongation of lattice parameter “c” from 9.143 to 9.830 Å with carbon concentration increase. Lattice expansion indicates the possibility of carbon substituting oxygen sites. Raman large area scan has revealed the presence of rutile, brookite and anatase for the undoped samples. On doping the rutile phase of TiO2 has shown to be suppressed by the presence of carbon atoms such that the doped samples consist of brookite and anatase phases only. The Eg1 mode of anatase of the undoped TNTs at 153. 78 cm-1 was red shifted by Δ9.78 cm-1 relative to the bulk anatase TiO2. This was attributed to decrease in particle size, presence of brookite and phonon confinement. Upon doping, the 9 mM C-TNTs, 27 mM TNTs and 75 mM TNTs have shown a red shift of Δ0. 09 cm-1, Δ1. 39 cm-1 and 1.81 cm-1 respectively, suggesting the incorporation of carbon in the TiO2 matrix. CRS depth profiling in the XZ direction has also validated the presence of a mixed anatase-brookite phase at Raman active modes 153.19 cm-1, 208.87 cm-1, 404.55 cm-1, 523.26 cm-1 and 648.55 cm-1. Photoluminescence spectra of carbon doped TiO2 showed two emission peaks at 398 nm attributed to annihilation of excitons while the broad peak at 400-460 nm was attributed to the presence of oxygen vacancies. The peak intensity of the 45 mM C-TNTs has shown a lower PL intensity suggesting that efficiency of charge separation was higher and recombination rate was lower than other carbon containing samples.
- Full Text:
- Date Issued: 2017
- Authors: Takata, Nwabisa
- Date: 2017
- Subjects: Nanotechnology Titanium dioxide Nanostructures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13194 , vital:39473
- Description: This study reveals the effects of doping on the morphological, structural and optical properties of titanium dioxide (TiO2) nanotubes (TNTs), synthesized by sol-gel template-assisted sol-gel technique. The nanotubes (TNTs) were prepared in anodic alumina membranes (AAM) with a pore diameter range of 110-210 nm by using titanium tetra butoxide as a sol-gel precursor and oxalic acid dihydrate as a dopant source. The synthesized nanotubes were evaluated using scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), confocal Raman spectroscopy (CRS) and photoluminescence spectroscopy (PL). SEM analysis has revealed the presence of closely-packed TNTs, with a modal external tube diameters of 150, 170, 210,190 and 210 nm for the un-doped TNTs, 9 mM carbon doped-TNTs (C-TNTs), 27 mM C-TNTs, 45 mM C-TNTs and 75 mM C-TNTs respectively. The diameters are consistent with the AAM diameter range. EDX spectra revealed the presence of Ti peaks at 0.45 and 4.9 keV corresponding to Kα1 and Kβ1 emission lines respectively. Oxygen exhibits a signal at 0.5 keV corresponding to Kα1 emission line. The occurrence of these peaks in the EDX spectra endorses the existence of Ti and O atoms in the prepared titanium dioxide nanotubes. FTIR spectroscopy has revealed the presence of vibration modes at 580-660 cm-1 indicating the presence of Ti-O bonds and additional vibration modes at 2324 cm-1 resulting from C-O stretching in the C-TNTs. The XRD analysis has revealed the presence of a mixed anatase-brookite phase with diffraction peaks at 2θ angles of 25.49⁰, 38.11⁰, 40.60º, 48.14⁰, 54.58⁰, 63.00⁰, 70.11⁰ and 75.66⁰. Additionally, XRD analysis has revealed elongation of lattice parameter “c” from 9.143 to 9.830 Å with carbon concentration increase. Lattice expansion indicates the possibility of carbon substituting oxygen sites. Raman large area scan has revealed the presence of rutile, brookite and anatase for the undoped samples. On doping the rutile phase of TiO2 has shown to be suppressed by the presence of carbon atoms such that the doped samples consist of brookite and anatase phases only. The Eg1 mode of anatase of the undoped TNTs at 153. 78 cm-1 was red shifted by Δ9.78 cm-1 relative to the bulk anatase TiO2. This was attributed to decrease in particle size, presence of brookite and phonon confinement. Upon doping, the 9 mM C-TNTs, 27 mM TNTs and 75 mM TNTs have shown a red shift of Δ0. 09 cm-1, Δ1. 39 cm-1 and 1.81 cm-1 respectively, suggesting the incorporation of carbon in the TiO2 matrix. CRS depth profiling in the XZ direction has also validated the presence of a mixed anatase-brookite phase at Raman active modes 153.19 cm-1, 208.87 cm-1, 404.55 cm-1, 523.26 cm-1 and 648.55 cm-1. Photoluminescence spectra of carbon doped TiO2 showed two emission peaks at 398 nm attributed to annihilation of excitons while the broad peak at 400-460 nm was attributed to the presence of oxygen vacancies. The peak intensity of the 45 mM C-TNTs has shown a lower PL intensity suggesting that efficiency of charge separation was higher and recombination rate was lower than other carbon containing samples.
- Full Text:
- Date Issued: 2017
The effect of fire management on chemical and physical properties of rangelands
- Authors: Magomani, Matimba Israel
- Date: 2017
- Subjects: Rangelands -- Fire management Soil ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6191 , vital:29506
- Description: The use of fire in rangeland has become standard practice for decades; however, there is no shared understanding of how fire affects soil properties. The exact relationship between fire and soil properties is still yet to be understood. The differences in fire frequency, fire intensity, fire severity, the period between fire and sampling resulted in contradictory results amongst studies. A long-term trial at the University of Fort Hare provides a valuable experimental layout for fire research. The trial was established in 1980 with the aim of investigating the effect of burning frequency on vegetation species composition and biomass production. The objective of this study was however to determine the effect of fire management on soil chemical and physical properties under the long-term burning experiment. The treatments of the study site were: no burn (K), annual (B1), biennial (B2), triennial (B3), quadrennial (B4) and sexennial (B6) burns. A line intercept sampling technique was used to collect the soil samples from the surface (0 to 75 mm) for both chemical and physical analysis. All Burning treatments significantly (p < 0.05) increased the bulk density (Db), soil pH, total cations, Magnesium (Mg) and Calcium (Ca), but reduced the soil porosity and exchangeable acidity when compared to the control. Hydraulic conductivity (Ks), water conducting macroporosity (WCM) and total nitrogen were reduced under more frequent burning treatments (B1, B2), as compared to less frequent burning treatments (B3, B4, B6). The aggregate stability showed an opposite trend. Total organic carbon (TOC) was reduced only under annual burning treatment. Burning frequencies did not impact the extractable Phosphorus (p), Potassium (K), Sodium, soil water repellency and water content significantly (P > 0.05). The risk associated with annual burning showed in this study might facilitate processes such as overflow that lead to soil degradation. Triennial burning in rangeland ecosystem supports soil conservation practices. Further studies that measure the quality of rangeland in triennial burning is necessary.
- Full Text:
- Date Issued: 2017
- Authors: Magomani, Matimba Israel
- Date: 2017
- Subjects: Rangelands -- Fire management Soil ecology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6191 , vital:29506
- Description: The use of fire in rangeland has become standard practice for decades; however, there is no shared understanding of how fire affects soil properties. The exact relationship between fire and soil properties is still yet to be understood. The differences in fire frequency, fire intensity, fire severity, the period between fire and sampling resulted in contradictory results amongst studies. A long-term trial at the University of Fort Hare provides a valuable experimental layout for fire research. The trial was established in 1980 with the aim of investigating the effect of burning frequency on vegetation species composition and biomass production. The objective of this study was however to determine the effect of fire management on soil chemical and physical properties under the long-term burning experiment. The treatments of the study site were: no burn (K), annual (B1), biennial (B2), triennial (B3), quadrennial (B4) and sexennial (B6) burns. A line intercept sampling technique was used to collect the soil samples from the surface (0 to 75 mm) for both chemical and physical analysis. All Burning treatments significantly (p < 0.05) increased the bulk density (Db), soil pH, total cations, Magnesium (Mg) and Calcium (Ca), but reduced the soil porosity and exchangeable acidity when compared to the control. Hydraulic conductivity (Ks), water conducting macroporosity (WCM) and total nitrogen were reduced under more frequent burning treatments (B1, B2), as compared to less frequent burning treatments (B3, B4, B6). The aggregate stability showed an opposite trend. Total organic carbon (TOC) was reduced only under annual burning treatment. Burning frequencies did not impact the extractable Phosphorus (p), Potassium (K), Sodium, soil water repellency and water content significantly (P > 0.05). The risk associated with annual burning showed in this study might facilitate processes such as overflow that lead to soil degradation. Triennial burning in rangeland ecosystem supports soil conservation practices. Further studies that measure the quality of rangeland in triennial burning is necessary.
- Full Text:
- Date Issued: 2017
The effect of phosphorus fertilizer application on growth, biomass and nutritive value of Pigeon pea (Cajanus cajan (L.) Millsp.) varieties in Alice, South Africa
- Authors: Mpabanga, Nkosi
- Date: 2017
- Subjects: Phosphatic fertilizers Soil fertility Plants -- Effect of phosphorus on
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6180 , vital:29501
- Description: Low soil fertility has been identified to be among the major causes of low pasture quantity and quality. Scarcity of high quality forage mainly during the dry season threatens animal productivity in some areas of South Africa, thus the need for identifying livestock feed alternatives. Pigeon pea is a woody legume that has continually been an important shrub in agroforestry and can provide protein-rich livestock feed during times of shortage. Soil fertility to support the production of pigeon pea can be enhanced by application of fertilisers. Therefore, this study was carried out firstly, to determine the effect of phosphorus fertiliser on the growth performance and biomass production of three pigeon pea varieties, and secondly, to investigate the influence of phosphorus application on the nutrient and anti-nutrient content of three pigeon pea varieties. The field experiment was done at the University of Fort Hare research farm in Alice, South Africa. The factors investigated were three pigeon pea varieties namely Chitedze 1, Chitedze 2 and CIMMYT 1 and three phosphorus fertiliser application rates of 0, 40 and 60 kg P/ha. The study was a 3× 3 factorial experiment set up in a randomised complete block design and was replicated three times. The growth performance attributes evaluated in this study include the number of branches, plant height and root collar diameter. Root collar diameter was not significantly (p>0.05) different among the pigeon pea varieties and phosphorus levels. Likewise, the application of phosphorus was not significant (p>0.05) on plant height and the number of branches of all the varieties. However, when P level was varied, there were significant differences among the varieties, and so were the interaction (p<0.05) between variety and phosphorus on plant height and the number of branches. There was no significant (p>0.05) difference among the phosphorus levels on the fresh leaf yield of Chitedze 1 and Chitedze 2, but phosphorus application at 40 kg P/ha increased the fresh leaf yield of CIMMYT 1. Phosphorus application at 60 kg P/ha increased (p<0.05) the dry matter content of Chitedze 1 and Chitedze 2. Furthermore, the results of the trial show that the application of 40 kg P/ha and 60 kg P/ha increased (p<0.05) the dry matter yield of the varieties CIMMYT 1 and Chitedze 2, respectively. The effects of phosphorus application on the nutrient composition of the three pigeon pea varieties varied. The composition of hemicellulose of all the varieties was significantly (p<0.05) increased by the application of 40 kg P/ha. Conversely, the concentration of crude protein, phosphorus, copper and iron, and the calcium to phosphorus ratio of all the pigeon pea varieties was not significantly (p>0.05) affected by phosphorus application and there was no interactive effect of variety and phosphorus. The proximate compositions of fat, total non-structural carbohydrates, ash, neutral detergent fibre, acid detergent fibre, cellulose, neutral detergent insoluble nitrogen, acid detergent insoluble nitrogen of the pigeon pea varieties varied significantly (p<0.05) at different phosphorus application levels. There was an interactive (p<0.05) effect of variety and the level of phosphorus on the concentration of calcium (Ca), potassium (K), magnesium (Mg), sodium, zinc, manganese, and the K/(Ca+Mg) ratio. The digestible dry matter, dry matter intake and the relative feed value were significantly (p<0.05) different among the pigeon pea varieties at varying phosphorus levels. The anti-nutrient composition of Chitedze 2 was not significantly (p>0.05) affected by phosphorus application but the concentration of phenols and saponins of Chitedze 1 was significantly (p<0.05) increased when 60 kg P/ha was applied, but these anti-nutrients were reduced (p<0.05) for CIMMYT 1 at 60 kg P/ha. It can be concluded that phosphorus application influences the biomass production and chemical composition while the optimum phosphorus level vary among the pigeon pea varieties.
- Full Text:
- Date Issued: 2017
- Authors: Mpabanga, Nkosi
- Date: 2017
- Subjects: Phosphatic fertilizers Soil fertility Plants -- Effect of phosphorus on
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6180 , vital:29501
- Description: Low soil fertility has been identified to be among the major causes of low pasture quantity and quality. Scarcity of high quality forage mainly during the dry season threatens animal productivity in some areas of South Africa, thus the need for identifying livestock feed alternatives. Pigeon pea is a woody legume that has continually been an important shrub in agroforestry and can provide protein-rich livestock feed during times of shortage. Soil fertility to support the production of pigeon pea can be enhanced by application of fertilisers. Therefore, this study was carried out firstly, to determine the effect of phosphorus fertiliser on the growth performance and biomass production of three pigeon pea varieties, and secondly, to investigate the influence of phosphorus application on the nutrient and anti-nutrient content of three pigeon pea varieties. The field experiment was done at the University of Fort Hare research farm in Alice, South Africa. The factors investigated were three pigeon pea varieties namely Chitedze 1, Chitedze 2 and CIMMYT 1 and three phosphorus fertiliser application rates of 0, 40 and 60 kg P/ha. The study was a 3× 3 factorial experiment set up in a randomised complete block design and was replicated three times. The growth performance attributes evaluated in this study include the number of branches, plant height and root collar diameter. Root collar diameter was not significantly (p>0.05) different among the pigeon pea varieties and phosphorus levels. Likewise, the application of phosphorus was not significant (p>0.05) on plant height and the number of branches of all the varieties. However, when P level was varied, there were significant differences among the varieties, and so were the interaction (p<0.05) between variety and phosphorus on plant height and the number of branches. There was no significant (p>0.05) difference among the phosphorus levels on the fresh leaf yield of Chitedze 1 and Chitedze 2, but phosphorus application at 40 kg P/ha increased the fresh leaf yield of CIMMYT 1. Phosphorus application at 60 kg P/ha increased (p<0.05) the dry matter content of Chitedze 1 and Chitedze 2. Furthermore, the results of the trial show that the application of 40 kg P/ha and 60 kg P/ha increased (p<0.05) the dry matter yield of the varieties CIMMYT 1 and Chitedze 2, respectively. The effects of phosphorus application on the nutrient composition of the three pigeon pea varieties varied. The composition of hemicellulose of all the varieties was significantly (p<0.05) increased by the application of 40 kg P/ha. Conversely, the concentration of crude protein, phosphorus, copper and iron, and the calcium to phosphorus ratio of all the pigeon pea varieties was not significantly (p>0.05) affected by phosphorus application and there was no interactive effect of variety and phosphorus. The proximate compositions of fat, total non-structural carbohydrates, ash, neutral detergent fibre, acid detergent fibre, cellulose, neutral detergent insoluble nitrogen, acid detergent insoluble nitrogen of the pigeon pea varieties varied significantly (p<0.05) at different phosphorus application levels. There was an interactive (p<0.05) effect of variety and the level of phosphorus on the concentration of calcium (Ca), potassium (K), magnesium (Mg), sodium, zinc, manganese, and the K/(Ca+Mg) ratio. The digestible dry matter, dry matter intake and the relative feed value were significantly (p<0.05) different among the pigeon pea varieties at varying phosphorus levels. The anti-nutrient composition of Chitedze 2 was not significantly (p>0.05) affected by phosphorus application but the concentration of phenols and saponins of Chitedze 1 was significantly (p<0.05) increased when 60 kg P/ha was applied, but these anti-nutrients were reduced (p<0.05) for CIMMYT 1 at 60 kg P/ha. It can be concluded that phosphorus application influences the biomass production and chemical composition while the optimum phosphorus level vary among the pigeon pea varieties.
- Full Text:
- Date Issued: 2017