Seasonal physiological responses in the Cape Rockjumper (Chaetops frenatus): a Fynbos endemic bird shows limited capacity to deal with temperature extremes
- Authors: Oswald, Krista Natasha
- Date: 2016
- Subjects: Endemic birds -- South Africa Fynbos ecology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/12994 , vital:27142
- Description: The Fynbos biome in south-western South Africa is a global biodiversity hotspot vulnerable to climate change. Of the six Fynbos-endemic passerines, Cape Rockjumpers (hereafter Rockjumpers; Chaetops frenatus) are most vulnerable to increases in temperature, with population declines correlated with warming, and low physiological heat thresholds. Rockjumper’s preferred mountain habitat is predicted to decrease as they lack opportunity to move to cooler regions as temperatures warm. As Rockjumpers currently occupy the coldest regions of the Fynbos, I hypothesized their thermal physiology would show cold adaptation at the expense of lowered ability to cope with higher temperatures. I aimed to determine the seasonal 1) maintenance metabolism and cold tolerance, and 2) thermoregulatory responses to high temperatures of Rockjumpers. I measured seasonal maintenance metabolic rate, thermal conductance, and maximum thermogenic capacity. I also measured seasonal resting metabolic rate, evaporative water loss, evaporative cooling efficiency, and body temperature at high air temperatures. In winter, Rockjumpers had higher maximum thermogenic capacity, lower maintenance metabolic rate, and lower thermal conductance. Lower maintenance metabolic rates (and thus, lower metabolic heat production) combined with the decreased thermal conductance, confers substantial energy savings in winter. The increased winter maximum thermogenic capacity of Rockjumpers was expected, although the mean seasonal values fell below those expected for a ~ 50 g bird using a global data set, suggesting Rockjumpers are not especially cold tolerant. I further show that in summer Rockjumpers had higher elevations in resting metabolic rates, evaporative water loss, and body temperature, denoting higher rates of heat production and lower heat thresholds in summer compared to winter. My results suggest that Rockjumpers are best suited for relatively mild Krista Oswald Dissertation Chapter 1: General Introduction temperatures. While I found further support for a physiological basis for declining Rockjumper populations, further studies on other mechanisms Rockjumpers may possess to cope with climate warming (e.g. behavioural adjustments) are needed in order to truly understand their vulnerability to climate change.
- Full Text:
- Date Issued: 2016
- Authors: Oswald, Krista Natasha
- Date: 2016
- Subjects: Endemic birds -- South Africa Fynbos ecology -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/12994 , vital:27142
- Description: The Fynbos biome in south-western South Africa is a global biodiversity hotspot vulnerable to climate change. Of the six Fynbos-endemic passerines, Cape Rockjumpers (hereafter Rockjumpers; Chaetops frenatus) are most vulnerable to increases in temperature, with population declines correlated with warming, and low physiological heat thresholds. Rockjumper’s preferred mountain habitat is predicted to decrease as they lack opportunity to move to cooler regions as temperatures warm. As Rockjumpers currently occupy the coldest regions of the Fynbos, I hypothesized their thermal physiology would show cold adaptation at the expense of lowered ability to cope with higher temperatures. I aimed to determine the seasonal 1) maintenance metabolism and cold tolerance, and 2) thermoregulatory responses to high temperatures of Rockjumpers. I measured seasonal maintenance metabolic rate, thermal conductance, and maximum thermogenic capacity. I also measured seasonal resting metabolic rate, evaporative water loss, evaporative cooling efficiency, and body temperature at high air temperatures. In winter, Rockjumpers had higher maximum thermogenic capacity, lower maintenance metabolic rate, and lower thermal conductance. Lower maintenance metabolic rates (and thus, lower metabolic heat production) combined with the decreased thermal conductance, confers substantial energy savings in winter. The increased winter maximum thermogenic capacity of Rockjumpers was expected, although the mean seasonal values fell below those expected for a ~ 50 g bird using a global data set, suggesting Rockjumpers are not especially cold tolerant. I further show that in summer Rockjumpers had higher elevations in resting metabolic rates, evaporative water loss, and body temperature, denoting higher rates of heat production and lower heat thresholds in summer compared to winter. My results suggest that Rockjumpers are best suited for relatively mild Krista Oswald Dissertation Chapter 1: General Introduction temperatures. While I found further support for a physiological basis for declining Rockjumper populations, further studies on other mechanisms Rockjumpers may possess to cope with climate warming (e.g. behavioural adjustments) are needed in order to truly understand their vulnerability to climate change.
- Full Text:
- Date Issued: 2016
Seasonal variations of essential oil composition and some biological evaluation of Pelargonium inquinans (L.) Ait. South Africa
- Authors: Tembeni, Babalwa
- Date: 2016
- Subjects: Pelargoniums Essences and essential oils Medicinal plants
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6281 , vital:29537
- Description: Pelargonium inquinans which belongs to the family Geraniaceae, is an essential oil yielding plant. P. inquinans was collected from two different sites in Grahamstown (wild) and Alice, at the University of Fort Hare botanical garden. Authentication of the plant was done by Dr. T. Dold at Schonland herbarium, and the voucher specimen being T01. This study is focused at determining the chemical constituents and biological properties of the essential oils of wild and cultivated P. inquinans across different seasons, as the plant grows throughout the year. Seasonal collection of wild and cultivated P. inquinans was achieved in a duration of 12 months. 32 essential oil samples of P. inquinans were obtained by extraction using hydro-distillation technique for 3-4 hours. The chemical composition of the essential oils was determined using GC/MS and GC/FID. Amongst the 32 essential oils only 4 samples wild ( fresh stem and leaf) and cultivated ( fresh stem and leaf) from summer season were evaluated for analgesic activity using acetic acid induced writhings and hot plate nociception models in mice, anti-inflammatory activity was determined on the egg albumin- induced rat paw oedema in rats. The results obtained from GC-MS revealed a total of 169 components obtained from the leafstem, fresh/dry wild and cultivated P. inquinans. These essential oils showed a great deal of chemotaxonomic variation and similarity in the major and minor components along the season. In spring season the essential oils of wild and cultivated P. inquinans had abundance of hydrogenated sesquiterpenes (20.6percent-66.7percent). The major components were found to be α-caryophyllene (9.1percent-26.8percent), p-xylene (23.3percent-27.5percent), β-caryophyllene (11.4percent-30.9percent), o-xylene (6.3percent-39.4percent), β-thujene (8.7percent), isocaryophyllene (13.9percent), isoborneol (14.2percent), β-myrcene (5.7percent), geranyl acetate (13.8percent), toluene (7.9percent), β-gurjunene (18.5percent), α-cadinene (15.8percent), β-farnesene (14.2percent), 3-carene (12.1percent) and camphene (9.0percent). In summer season the essential oils of wild and cultivated P. inquinans were found to have abundance of hydrogenated sesquiterpenes (50.3percent- 63.0percent), oxygenated monoterpenes (30.4percent) and hydrogenated monoterpenes (20.8percent- 61.0percent). The major components were found to be α-caryophyllene (12.3percent-25.8percent), β-caryophyllene (15.1percent- 31.7percent), trans-caryophyllene (10.3percent- 17.8percent), phytol (14.2percent- 20.2percent), camphor (46.5percent), sabinene (27.8percent), elemol (18.1percent), z3-hexenyl isobutyrate (16.3percent), limonene (12.1percent), menthone (12.1percent)< E.E-β-farnesene (14.7percent), palmitic acid (9.6percent), eugenol (9.4percent), cis- β-ocimene (8.7percent), α-terpineol (8.7percent), geranyl acetone (7.8percent), β- humulene (7.5percent). linoleic acid (7.4percent), trans-linalool oxide (7.4percent), β-bisabolene (7.1percent), cis- linalool oxide (7.1percent), ionone (6.9percent), caryophyllene oxide (6.9percent) and germacrene d (6.3percent). In autumn season the essential oils of wild and cultivated P. inquinans were found to be rich in hydrogenated sesquiterpenes (29.3percent- 65.2percent) and oxygenated sesquiterpenes (22.8percent- 31.4percent). The major components were found to be α-caryophyllene (15.5percent- 23.4percent), β-caryophyllene (15.2percent- 17.2percent), β-myrcene (7.7percent-13.8percent), β-humulene (8.7percent- 15.2percent), caryophyllene oxide (9.8- 16.2percent), trans- caryophyllene (16.7percent- 23.3percent), α-humulene (11.8percent- 18.6percent), linoleic acid (11.2percent), palmitic acid (10.4percent), phytol acetate (8.5percent), -longipinene (8.3percent) and citronellol (7.8percent). In winter season the essential oils of wild and cultivated P. inquinans were found to have abundance of hydrogenated sesquiterpenes (25.1percent- 48.6percent), oxygenated monoterpenes (47.6percent), oxygenated sesquiterpenes (22.2percent- 28.0percent). The major components were found to be β-caryophyllene (14.6percent- 23.0percent), α-caryophyllene (9.4percent- 18.0percent), trans- caryophyllene (12.2percent- 14.6percent), α-cedrene (26.2percent), germacrene –d-4-ol (16.8percent), 2,6-dihydroxyacetophenone (15.6percent), (+) epibicyclosesquiphellandrene (15.3percent), E-β- farnesene (13.0percent), β-phellandrene (11.7percent), 2-nitrophenol (9.5percent), palatinol (8.4percent), geranyl acetate (7.7percent) and linoleic acid (7.4percent). The oils from the wild and cultivated sources showed significant (p<0.05-0.001) decrease in number of writhes induced by the acetic acid compared to vehicle; caused significant (p<0.05-0.001) delay in reaction time on the hot plate at 60 and 90 min post-treatment and significantly (p<0.05-0.001) reduced oedema size caused by the egg albumin injection compared to the vehicle. The oils from the wild plant showed more potency compared to the cultivated. The essential oils of wild and cultivated P. inquinans showed qualitative, quantitative and chemotaxonomic variation with analgesic and anti-inflammatory activity. These essential oils need to be explored for further biological analysis because of the major components they contain.
- Full Text:
- Date Issued: 2016
- Authors: Tembeni, Babalwa
- Date: 2016
- Subjects: Pelargoniums Essences and essential oils Medicinal plants
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6281 , vital:29537
- Description: Pelargonium inquinans which belongs to the family Geraniaceae, is an essential oil yielding plant. P. inquinans was collected from two different sites in Grahamstown (wild) and Alice, at the University of Fort Hare botanical garden. Authentication of the plant was done by Dr. T. Dold at Schonland herbarium, and the voucher specimen being T01. This study is focused at determining the chemical constituents and biological properties of the essential oils of wild and cultivated P. inquinans across different seasons, as the plant grows throughout the year. Seasonal collection of wild and cultivated P. inquinans was achieved in a duration of 12 months. 32 essential oil samples of P. inquinans were obtained by extraction using hydro-distillation technique for 3-4 hours. The chemical composition of the essential oils was determined using GC/MS and GC/FID. Amongst the 32 essential oils only 4 samples wild ( fresh stem and leaf) and cultivated ( fresh stem and leaf) from summer season were evaluated for analgesic activity using acetic acid induced writhings and hot plate nociception models in mice, anti-inflammatory activity was determined on the egg albumin- induced rat paw oedema in rats. The results obtained from GC-MS revealed a total of 169 components obtained from the leafstem, fresh/dry wild and cultivated P. inquinans. These essential oils showed a great deal of chemotaxonomic variation and similarity in the major and minor components along the season. In spring season the essential oils of wild and cultivated P. inquinans had abundance of hydrogenated sesquiterpenes (20.6percent-66.7percent). The major components were found to be α-caryophyllene (9.1percent-26.8percent), p-xylene (23.3percent-27.5percent), β-caryophyllene (11.4percent-30.9percent), o-xylene (6.3percent-39.4percent), β-thujene (8.7percent), isocaryophyllene (13.9percent), isoborneol (14.2percent), β-myrcene (5.7percent), geranyl acetate (13.8percent), toluene (7.9percent), β-gurjunene (18.5percent), α-cadinene (15.8percent), β-farnesene (14.2percent), 3-carene (12.1percent) and camphene (9.0percent). In summer season the essential oils of wild and cultivated P. inquinans were found to have abundance of hydrogenated sesquiterpenes (50.3percent- 63.0percent), oxygenated monoterpenes (30.4percent) and hydrogenated monoterpenes (20.8percent- 61.0percent). The major components were found to be α-caryophyllene (12.3percent-25.8percent), β-caryophyllene (15.1percent- 31.7percent), trans-caryophyllene (10.3percent- 17.8percent), phytol (14.2percent- 20.2percent), camphor (46.5percent), sabinene (27.8percent), elemol (18.1percent), z3-hexenyl isobutyrate (16.3percent), limonene (12.1percent), menthone (12.1percent)< E.E-β-farnesene (14.7percent), palmitic acid (9.6percent), eugenol (9.4percent), cis- β-ocimene (8.7percent), α-terpineol (8.7percent), geranyl acetone (7.8percent), β- humulene (7.5percent). linoleic acid (7.4percent), trans-linalool oxide (7.4percent), β-bisabolene (7.1percent), cis- linalool oxide (7.1percent), ionone (6.9percent), caryophyllene oxide (6.9percent) and germacrene d (6.3percent). In autumn season the essential oils of wild and cultivated P. inquinans were found to be rich in hydrogenated sesquiterpenes (29.3percent- 65.2percent) and oxygenated sesquiterpenes (22.8percent- 31.4percent). The major components were found to be α-caryophyllene (15.5percent- 23.4percent), β-caryophyllene (15.2percent- 17.2percent), β-myrcene (7.7percent-13.8percent), β-humulene (8.7percent- 15.2percent), caryophyllene oxide (9.8- 16.2percent), trans- caryophyllene (16.7percent- 23.3percent), α-humulene (11.8percent- 18.6percent), linoleic acid (11.2percent), palmitic acid (10.4percent), phytol acetate (8.5percent), -longipinene (8.3percent) and citronellol (7.8percent). In winter season the essential oils of wild and cultivated P. inquinans were found to have abundance of hydrogenated sesquiterpenes (25.1percent- 48.6percent), oxygenated monoterpenes (47.6percent), oxygenated sesquiterpenes (22.2percent- 28.0percent). The major components were found to be β-caryophyllene (14.6percent- 23.0percent), α-caryophyllene (9.4percent- 18.0percent), trans- caryophyllene (12.2percent- 14.6percent), α-cedrene (26.2percent), germacrene –d-4-ol (16.8percent), 2,6-dihydroxyacetophenone (15.6percent), (+) epibicyclosesquiphellandrene (15.3percent), E-β- farnesene (13.0percent), β-phellandrene (11.7percent), 2-nitrophenol (9.5percent), palatinol (8.4percent), geranyl acetate (7.7percent) and linoleic acid (7.4percent). The oils from the wild and cultivated sources showed significant (p<0.05-0.001) decrease in number of writhes induced by the acetic acid compared to vehicle; caused significant (p<0.05-0.001) delay in reaction time on the hot plate at 60 and 90 min post-treatment and significantly (p<0.05-0.001) reduced oedema size caused by the egg albumin injection compared to the vehicle. The oils from the wild plant showed more potency compared to the cultivated. The essential oils of wild and cultivated P. inquinans showed qualitative, quantitative and chemotaxonomic variation with analgesic and anti-inflammatory activity. These essential oils need to be explored for further biological analysis because of the major components they contain.
- Full Text:
- Date Issued: 2016
Single station TEC modelling during storm conditions
- Authors: Uwamahoro, Jean Claude
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3812 , vital:20545
- Description: It has been shown in ionospheric research that modelling total electron content (TEC) during storm conditions is a big challenge. In this study, mathematical equations were developed to estimate TEC over Sutherland (32.38oS, 20.81oE), during storm conditions, using the Empirical Orthogonal Function (EOF) analysis, combined with regression analysis. TEC was derived from GPS observations and a geomagnetic storm was defined for Dst ≤ -50 nT. The inputs for the model were chosen based on the factors that influence TEC variation, such as diurnal, seasonal, solar and geomagnetic activity variation, and these were represented by hour of the day, day number of the year, F10.7 and A index respectively. The EOF model was developed using GPS TEC data from 1999 to 2013 and tested on different storms. For the model validation (interpolation), three storms were chosen in 2000 (solar maximum period) and three others in 2006 (solar minimum period), while for extrapolation six storms including three in 2014 and three in 2015 were chosen. Before building the model, TEC values for the selected 2000 and 2006 storms were removed from the dataset used to construct the model in order to make the model validation independent on data. A comparison of the observed and modelled TEC showed that the EOF model works well for storms with non-significant ionospheric TEC response and storms that occurred during periods of low solar activity. High correlation coefficients between the observed and modelled TEC were obtained showing that the model covers most of the information contained in the observed TEC. Furthermore, it has been shown that the EOF model developed for a specific station may be used to estimate TEC over other locations within a latitudinal and longitudinal coverage of 8.7o and 10.6o respectively. This is an important result as it reduces the data dimensionality problem for computational purposes. It may therefore not be necessary for regional storm-time TEC modelling to compute TEC data for all the closest GPS receiver stations since most of the needed information can be extracted from measurements at one location.
- Full Text:
- Date Issued: 2016
- Authors: Uwamahoro, Jean Claude
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3812 , vital:20545
- Description: It has been shown in ionospheric research that modelling total electron content (TEC) during storm conditions is a big challenge. In this study, mathematical equations were developed to estimate TEC over Sutherland (32.38oS, 20.81oE), during storm conditions, using the Empirical Orthogonal Function (EOF) analysis, combined with regression analysis. TEC was derived from GPS observations and a geomagnetic storm was defined for Dst ≤ -50 nT. The inputs for the model were chosen based on the factors that influence TEC variation, such as diurnal, seasonal, solar and geomagnetic activity variation, and these were represented by hour of the day, day number of the year, F10.7 and A index respectively. The EOF model was developed using GPS TEC data from 1999 to 2013 and tested on different storms. For the model validation (interpolation), three storms were chosen in 2000 (solar maximum period) and three others in 2006 (solar minimum period), while for extrapolation six storms including three in 2014 and three in 2015 were chosen. Before building the model, TEC values for the selected 2000 and 2006 storms were removed from the dataset used to construct the model in order to make the model validation independent on data. A comparison of the observed and modelled TEC showed that the EOF model works well for storms with non-significant ionospheric TEC response and storms that occurred during periods of low solar activity. High correlation coefficients between the observed and modelled TEC were obtained showing that the model covers most of the information contained in the observed TEC. Furthermore, it has been shown that the EOF model developed for a specific station may be used to estimate TEC over other locations within a latitudinal and longitudinal coverage of 8.7o and 10.6o respectively. This is an important result as it reduces the data dimensionality problem for computational purposes. It may therefore not be necessary for regional storm-time TEC modelling to compute TEC data for all the closest GPS receiver stations since most of the needed information can be extracted from measurements at one location.
- Full Text:
- Date Issued: 2016
Site Fidelity of southern right (Eubalaena australis) and humpback whales (Megaptera novaeangliae) in Algoa Bay, South Africa
- Authors: Drost, Eduard F
- Date: 2016
- Subjects: Marine mammals -- South Africa -- Algoa Bay Southern right whale -- South Africa -- Algoa Bay Humpback whale -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/21735 , vital:29742
- Description: Mysticetes, or baleen whales, make up one of two sub-orders of the Order Cetacea within the Class Mammalia (Drikamer et al, 2013). It contains three families, each characterized by baleen plates (Drikamer et al, 2013). These baleen plates consist of keratin that replaced the tooth structures for feeding in these mammals (Drikamer et al, 2013). Other biological characteristics of these animals include paired external nares (blowholes), a sternum consisting of a single bone, symmetrical skull and the most conspicuous of all, the body length of between ten to thirty metres (Drikamer et al, 2013). It is thought that the size characteristic was probably the main factor when categorising them as cetaceans, with the Latin word ‘Cetus’ referring to ‘sea monster’ (Carnaby, 2006). In this literature review, the focus will fall on two species of mysticetes from separate families, namely that of the southern right whale, Eubalaena australis of the Balaenidae family, and the humpback whale, Megaptera novaeangliae of the Balaenopteridae family. Emphasis in this review will fall on the aspect of site fidelity of the mother-calf pairs.
- Full Text:
- Date Issued: 2016
- Authors: Drost, Eduard F
- Date: 2016
- Subjects: Marine mammals -- South Africa -- Algoa Bay Southern right whale -- South Africa -- Algoa Bay Humpback whale -- South Africa -- Algoa Bay
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/21735 , vital:29742
- Description: Mysticetes, or baleen whales, make up one of two sub-orders of the Order Cetacea within the Class Mammalia (Drikamer et al, 2013). It contains three families, each characterized by baleen plates (Drikamer et al, 2013). These baleen plates consist of keratin that replaced the tooth structures for feeding in these mammals (Drikamer et al, 2013). Other biological characteristics of these animals include paired external nares (blowholes), a sternum consisting of a single bone, symmetrical skull and the most conspicuous of all, the body length of between ten to thirty metres (Drikamer et al, 2013). It is thought that the size characteristic was probably the main factor when categorising them as cetaceans, with the Latin word ‘Cetus’ referring to ‘sea monster’ (Carnaby, 2006). In this literature review, the focus will fall on two species of mysticetes from separate families, namely that of the southern right whale, Eubalaena australis of the Balaenidae family, and the humpback whale, Megaptera novaeangliae of the Balaenopteridae family. Emphasis in this review will fall on the aspect of site fidelity of the mother-calf pairs.
- Full Text:
- Date Issued: 2016
Solid waste management and its implications on livestock health in selected abattoirs of the Eastern Cape province, South Africa
- Authors: Nongcula, Vikhaya Vincent
- Date: 2016
- Subjects: Refuse and refuse disposal -- South Africa -- Eastern Cape Recycling (Waste, etc.) -- South Africa -- Eastern Cape Livestock -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12293 , vital:39250
- Description: An investigation was carried out on the implications of solid waste management on livestock health in selected abattoirs of the Eastern Cape Province of South Africa. The main objective of the study was to determine the effects of solid waste management on livestock health as well as to assess the perceptions of solid waste management among livestock owners. In this study, a questionnaire was designed to obtain information regarding farmer’s perceptions on solid waste and how it affects animal health, and active abattoir inspection were conducted to assess how solid waste affects the animal. The results revealed that most farmers practiced poor solid waste management as a result animals were exposed to ingestion of indigestible materials. This was confirmed on the basis that most farmers (99.2 percent) had no municipal dustbins in their areas, no recycling programmes (94.2 percent) and 51.7percent of the farmers disposed their litter in open land as a result most farmers (75.9percent) agreed that solid waste management was a problem in their areas. Due to poor solid waste management, 53.8 percent of the farmers confirmed that they have seen livestock ingesting indigestible materials such as plastics and 69.0 percent of the farmers suspected that ingestion of such materials caused some of the health issue experienced by animals on their farm. The active abattoir inspection revealed that plastics, wires, nails, ropes, stones, bones, cloths, hairs and polybezoars were frequently occurring in slaughter cattle stomachs particularly in the rumen and reticulum and in female and older cattle. As a result most affected cattle were in thin and average condition. The effect of indigestible objects on body condition score (BCS) and organ condemnation was determined using linear regression analysis test; where BCS and condemnation were the dependent variables and indigestible objects were the independent variables. The results revealed that some organs were condemned in affected cattle and the statistical analysis showed that there was no significant difference (p< 0.05) between the prevalence of indigestible materials and organ condemnation. However, there was a significant difference between the prevalence of indigestible materials and body condition score of affected cattle although they were coming from different farming systems. It was concluded that livestock health was affected by solid waste and recommended that practice of good animal husbandry and proper solid waste management be practiced to overcome the implications (poor body condition score) of solid waste in livestock. Furthermore, close cooperation between government extension officers, commercial and communal farmers in knowledge-sharing regarding health issues of livestock is recommended.
- Full Text:
- Date Issued: 2016
- Authors: Nongcula, Vikhaya Vincent
- Date: 2016
- Subjects: Refuse and refuse disposal -- South Africa -- Eastern Cape Recycling (Waste, etc.) -- South Africa -- Eastern Cape Livestock -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12293 , vital:39250
- Description: An investigation was carried out on the implications of solid waste management on livestock health in selected abattoirs of the Eastern Cape Province of South Africa. The main objective of the study was to determine the effects of solid waste management on livestock health as well as to assess the perceptions of solid waste management among livestock owners. In this study, a questionnaire was designed to obtain information regarding farmer’s perceptions on solid waste and how it affects animal health, and active abattoir inspection were conducted to assess how solid waste affects the animal. The results revealed that most farmers practiced poor solid waste management as a result animals were exposed to ingestion of indigestible materials. This was confirmed on the basis that most farmers (99.2 percent) had no municipal dustbins in their areas, no recycling programmes (94.2 percent) and 51.7percent of the farmers disposed their litter in open land as a result most farmers (75.9percent) agreed that solid waste management was a problem in their areas. Due to poor solid waste management, 53.8 percent of the farmers confirmed that they have seen livestock ingesting indigestible materials such as plastics and 69.0 percent of the farmers suspected that ingestion of such materials caused some of the health issue experienced by animals on their farm. The active abattoir inspection revealed that plastics, wires, nails, ropes, stones, bones, cloths, hairs and polybezoars were frequently occurring in slaughter cattle stomachs particularly in the rumen and reticulum and in female and older cattle. As a result most affected cattle were in thin and average condition. The effect of indigestible objects on body condition score (BCS) and organ condemnation was determined using linear regression analysis test; where BCS and condemnation were the dependent variables and indigestible objects were the independent variables. The results revealed that some organs were condemned in affected cattle and the statistical analysis showed that there was no significant difference (p< 0.05) between the prevalence of indigestible materials and organ condemnation. However, there was a significant difference between the prevalence of indigestible materials and body condition score of affected cattle although they were coming from different farming systems. It was concluded that livestock health was affected by solid waste and recommended that practice of good animal husbandry and proper solid waste management be practiced to overcome the implications (poor body condition score) of solid waste in livestock. Furthermore, close cooperation between government extension officers, commercial and communal farmers in knowledge-sharing regarding health issues of livestock is recommended.
- Full Text:
- Date Issued: 2016
Spatio-temporal analyses of woody vegetation cover using remote sensing techniques: the case of Alice - King Williams Town route, Eastern Cape, South Africa
- Authors: Fundisi, Emmanuel
- Date: 2016
- Subjects: Woody plants -- South Africa -- Eastern Cape Vegetation classification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1830 , vital:27564
- Description: Expansion of woody vegetation results in the transformation of a grass-dominated ecosystem to a tree-dominated ecosystem causing land degradation in most semi-arid areas. The imbalance in the natural ecosystem between herbaceous plants and woody vegetation poses a threat to the natural environment. Such changes alter the flow, availability and quality of nutrient resources in the biogeochemical cycle. Most of the dominating woody plants are often unpalatable to domestic livestock. Therefore, the objective is to assess the spatial extent of woody vegetation over time. Knowledge of the spatial and temporal characteristics of woody vegetation dynamics will enable the development of management plans. These characteristics can be derived using remote sensing techniques which have become efficient in such studies. This study aimed to characterize woody vegetation dynamics along the route between Alice and King Williams’s town in Eastern Cape Province South Africa using Landsat data. This aim was achieved by focussing on three specific objectives. The first objective was to compare the performance of multispectral data and Normalized Difference Vegetation Index (NDVI) data of Landsat imagery in mapping woody vegetation cover. The second objective was to investigate the effect of the spatial resolution of remotely-sensed data on discrimination of woody vegetation from other land cover types. The third objective characterised woody vegetation dynamics between 1986 and 2013/2014 using the results from the first objective. The study used Landsat imagery acquired in November or February of 1986, 1994/1995, 2002/2003 and 2013/2014. Due to lack of data which covered the study area two separate dates (November and February) where used for the study resulting in naming the study area western and eastern parts. Unsupervised classification was performed on the multispectral, NDVI and pan-sharpened images to generate four generic land cover classes, namely water, bare land, grassland and woodland. Accuracy assessments of the classified images was done using error matrix. The results showed that the classification based on NDVI images yielded a better overall accuracy than the classification based on multispectral images for the western (83 percent and 75 percent, respectively) and eastern (82 percent and 76 percent, respectively) parts of the study area. Similarly, pan-sharpening resulted in better overall classification accuracy than multispectral, but comparable to the classification of the NDVI images for both the western (82 percent) and eastern (83 percent) parts of the study area. Remote sensing is an effective tool in assessing changes in the physical environment. Landsat imagery is suitable in assessing land cover dynamics given the long-term and free availability of the image. In addition, the large spatial coverage it provides, enables Landsat data to be used on studies that have wide spatial coverage. Classification for the purpose of time-series analysis was then performed on the NDVI images of each date (1986, 1994/1995, 2002/2003 and 2013/2014). Both woody vegetation and grassland experienced changes from 1986 to 2013/2014 with grassland occupying (75 percent) compared to woodland (17 percent) in 1986. In the year 2013/14 grassland occupied 32 percent and woodland occupied 51 percent of the study area. The increase in woody vegetation in the study area can be attributed to livestock rearing and migration of people from the rural to urban areas post-Apartheid. The study output will aid in the development of a database on land cover distribution of the area between King William’s town and Alice town, providing useful information to decision-making and further studies on woody vegetation.
- Full Text:
- Date Issued: 2016
- Authors: Fundisi, Emmanuel
- Date: 2016
- Subjects: Woody plants -- South Africa -- Eastern Cape Vegetation classification -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1830 , vital:27564
- Description: Expansion of woody vegetation results in the transformation of a grass-dominated ecosystem to a tree-dominated ecosystem causing land degradation in most semi-arid areas. The imbalance in the natural ecosystem between herbaceous plants and woody vegetation poses a threat to the natural environment. Such changes alter the flow, availability and quality of nutrient resources in the biogeochemical cycle. Most of the dominating woody plants are often unpalatable to domestic livestock. Therefore, the objective is to assess the spatial extent of woody vegetation over time. Knowledge of the spatial and temporal characteristics of woody vegetation dynamics will enable the development of management plans. These characteristics can be derived using remote sensing techniques which have become efficient in such studies. This study aimed to characterize woody vegetation dynamics along the route between Alice and King Williams’s town in Eastern Cape Province South Africa using Landsat data. This aim was achieved by focussing on three specific objectives. The first objective was to compare the performance of multispectral data and Normalized Difference Vegetation Index (NDVI) data of Landsat imagery in mapping woody vegetation cover. The second objective was to investigate the effect of the spatial resolution of remotely-sensed data on discrimination of woody vegetation from other land cover types. The third objective characterised woody vegetation dynamics between 1986 and 2013/2014 using the results from the first objective. The study used Landsat imagery acquired in November or February of 1986, 1994/1995, 2002/2003 and 2013/2014. Due to lack of data which covered the study area two separate dates (November and February) where used for the study resulting in naming the study area western and eastern parts. Unsupervised classification was performed on the multispectral, NDVI and pan-sharpened images to generate four generic land cover classes, namely water, bare land, grassland and woodland. Accuracy assessments of the classified images was done using error matrix. The results showed that the classification based on NDVI images yielded a better overall accuracy than the classification based on multispectral images for the western (83 percent and 75 percent, respectively) and eastern (82 percent and 76 percent, respectively) parts of the study area. Similarly, pan-sharpening resulted in better overall classification accuracy than multispectral, but comparable to the classification of the NDVI images for both the western (82 percent) and eastern (83 percent) parts of the study area. Remote sensing is an effective tool in assessing changes in the physical environment. Landsat imagery is suitable in assessing land cover dynamics given the long-term and free availability of the image. In addition, the large spatial coverage it provides, enables Landsat data to be used on studies that have wide spatial coverage. Classification for the purpose of time-series analysis was then performed on the NDVI images of each date (1986, 1994/1995, 2002/2003 and 2013/2014). Both woody vegetation and grassland experienced changes from 1986 to 2013/2014 with grassland occupying (75 percent) compared to woodland (17 percent) in 1986. In the year 2013/14 grassland occupied 32 percent and woodland occupied 51 percent of the study area. The increase in woody vegetation in the study area can be attributed to livestock rearing and migration of people from the rural to urban areas post-Apartheid. The study output will aid in the development of a database on land cover distribution of the area between King William’s town and Alice town, providing useful information to decision-making and further studies on woody vegetation.
- Full Text:
- Date Issued: 2016
Stratigraphic interrelationships, sedimentology and post Karoo intrusions in the Katberg and Burgersdorp formations around the town of Whittlesea, Eastern Cape province, South Africa
- Authors: Mzana, Siphokazi Kwamnandi
- Date: 2016
- Subjects: Formations (Geology) -- South Africa -- Eastern Cape Sedimentology -- South Africa -- Eastern Cape Geology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15046 , vital:40157
- Description: Concentrating on the Katberg and Burgersdorp Formations, this research examined the sedimentary environments inter alia by conducting heavy mineral analysis, interpreting provenance and determining stratigraphic interrelationships of the two formations in the Tarkastad Subgroup (Beaufort Group, Karoo Supergroup) around the town of Whittlesea in the Eastern Cape Province of South Africa. It has been observed that the strata of the Katberg Formation are dominated by sandstones of a braided river system. On the other hand, the Burgersdorp Formation comprises mainly dark greyish-red mudstone, red shale with subordinate siltstone and red sandstone deposited on floodplains and channels of meandering rivers. The Katberg Formation becomes progressively less arenaceous to the north of the study area until it is virtually indistinguishable from the overlying Burgersdorp Formation. Dolerite dykes and sills that intruded the Karoo Supergroup disturbed and baked the sedimentary strata of the Tarkastad Subgroup as well as other Karoo successions. The Katberg formation is mostly found in elevated areas, commonly metamorphosed and capped by dolerite sills while the Burgersdorp is found in low lying areas and is less metamorphosed or not metamorphosed at all. Lithologies of the two formations and the Karoo dolerites have been geologically mapped and the interfingering relationship between the Burgersdorp and Katberg Formation is also shown on the map. Horizontal laminae, planar bedding and planar and trough cross-bedding characterise lithofacies in the two formations. The fossil hunt done during the course of the study did not yield any positive results in both formations. Initially, the pebbles from outcrops of the Katberg Formation in the East London area were described in hand specimen by Mountain (1939). This study took it further with petrographic- and modal analysis as well as grain size analysis for the sedimentary pebbles. Microscopic studies done on the rock samples collected in the study area revealed quartz and feldspar as the dominant constituents. Most of the feldspar is hazy as a result of dissolution and alteration to clays. Sparse sedimentary rock fragments and quartz overgrowths in some of the rocks and grains respectively, indicate phases of recycling from older sedimentary sources. Furthermore, the samples have a wide range of grain sizes, sorting, grain shapes and classification categories. Textural attributes of sediments such as mean grain size, sorting, skewness and kurtosis were used to characterise the nature of the transport processes and to reconstruct the depositional environment of the sediments. The sandstones of both the Katberg and Burgersdorp Formations are medium-grained and moderately sorted to moderately well sorted but the pebbles are very coarse- to coarse-grained. Deducing sediment provenance from the final product of a basin fill is anything but straight-forward because rocks break down and unstable minerals change during transportation along the pathways from source to basin and afterwards during diagenesis. Heavy mineral studies coupled with geochemical sandstone analysis were used to unravel the sources of sediments. Among the heavies found were opaque and non-opaque minerals which are highly resistant to weathering with zircon being the most dominant. The heavy mineral grains vary in shape from subround to angular-subround in shape. The integrated results of petrography, XRD, XRF and SEM/EDX were used to identify the source rock character and to evaluate the relative role of tectonics and climate in determining the geochemical composition of the Katberg and Burgersdorp sandstones. Sandstone composition was used to decipher the provenance and tectonic setting of source areas by standard triangular QtFL and QmFLt diagrams, tectonic setting discrimination diagrams and source rock composition diagrams to characterise the source rocks.
- Full Text:
- Date Issued: 2016
- Authors: Mzana, Siphokazi Kwamnandi
- Date: 2016
- Subjects: Formations (Geology) -- South Africa -- Eastern Cape Sedimentology -- South Africa -- Eastern Cape Geology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15046 , vital:40157
- Description: Concentrating on the Katberg and Burgersdorp Formations, this research examined the sedimentary environments inter alia by conducting heavy mineral analysis, interpreting provenance and determining stratigraphic interrelationships of the two formations in the Tarkastad Subgroup (Beaufort Group, Karoo Supergroup) around the town of Whittlesea in the Eastern Cape Province of South Africa. It has been observed that the strata of the Katberg Formation are dominated by sandstones of a braided river system. On the other hand, the Burgersdorp Formation comprises mainly dark greyish-red mudstone, red shale with subordinate siltstone and red sandstone deposited on floodplains and channels of meandering rivers. The Katberg Formation becomes progressively less arenaceous to the north of the study area until it is virtually indistinguishable from the overlying Burgersdorp Formation. Dolerite dykes and sills that intruded the Karoo Supergroup disturbed and baked the sedimentary strata of the Tarkastad Subgroup as well as other Karoo successions. The Katberg formation is mostly found in elevated areas, commonly metamorphosed and capped by dolerite sills while the Burgersdorp is found in low lying areas and is less metamorphosed or not metamorphosed at all. Lithologies of the two formations and the Karoo dolerites have been geologically mapped and the interfingering relationship between the Burgersdorp and Katberg Formation is also shown on the map. Horizontal laminae, planar bedding and planar and trough cross-bedding characterise lithofacies in the two formations. The fossil hunt done during the course of the study did not yield any positive results in both formations. Initially, the pebbles from outcrops of the Katberg Formation in the East London area were described in hand specimen by Mountain (1939). This study took it further with petrographic- and modal analysis as well as grain size analysis for the sedimentary pebbles. Microscopic studies done on the rock samples collected in the study area revealed quartz and feldspar as the dominant constituents. Most of the feldspar is hazy as a result of dissolution and alteration to clays. Sparse sedimentary rock fragments and quartz overgrowths in some of the rocks and grains respectively, indicate phases of recycling from older sedimentary sources. Furthermore, the samples have a wide range of grain sizes, sorting, grain shapes and classification categories. Textural attributes of sediments such as mean grain size, sorting, skewness and kurtosis were used to characterise the nature of the transport processes and to reconstruct the depositional environment of the sediments. The sandstones of both the Katberg and Burgersdorp Formations are medium-grained and moderately sorted to moderately well sorted but the pebbles are very coarse- to coarse-grained. Deducing sediment provenance from the final product of a basin fill is anything but straight-forward because rocks break down and unstable minerals change during transportation along the pathways from source to basin and afterwards during diagenesis. Heavy mineral studies coupled with geochemical sandstone analysis were used to unravel the sources of sediments. Among the heavies found were opaque and non-opaque minerals which are highly resistant to weathering with zircon being the most dominant. The heavy mineral grains vary in shape from subround to angular-subround in shape. The integrated results of petrography, XRD, XRF and SEM/EDX were used to identify the source rock character and to evaluate the relative role of tectonics and climate in determining the geochemical composition of the Katberg and Burgersdorp sandstones. Sandstone composition was used to decipher the provenance and tectonic setting of source areas by standard triangular QtFL and QmFLt diagrams, tectonic setting discrimination diagrams and source rock composition diagrams to characterise the source rocks.
- Full Text:
- Date Issued: 2016
Street tree composition, distribution and urban residents’ perceptions within and between Eastern Cape towns
- Authors: Gwedla, Nanamhla
- Date: 2016
- Subjects: Urbanization -- South Africa -- Eastern Cape , Urban ecology (Sociology) -- South Africa -- Eastern Cape , Tree planting -- South Africa -- Eastern Cape , Trees in cities -- Environmental aspects -- South Africa -- Eastern Cape , Urban forestry -- Law and legislation -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4702 , vital:20714
- Description: Promoting urban sustainability is vital in the face of rapid human and urban population growth. A core tenet of urban sustainability, urban forestry, is poised to “go global” with the intent of mitigating the negative environmental and social effects of urbanisation through green infrastructure, spaces and trees. Amongst these, the planting of street trees has become a major strategy. The public functions of street trees as demonstrated through the provision of ecosystem services are highly dependent on the structure, composition and diversity of tree species within the urban forest. The bulk of available literature on the composition, diversity and perceptions of residents regarding street trees has largely focused on the developed world, while the few in the developing world have been conducted at only one or two sites. The aim of this study was to investigate the composition, diversity and density of urban street trees in relation to the perceptions of local residents and horticulturists, across a range of ecological and social contexts. To do this, the species composition, diversity and dominance of street trees planted in 10 randomly selected Eastern Cape towns was assessed. Within each town ten replicate 200 m transects were located in three different suburbs. Perceptions and appreciation of street trees were assessed by 1 200 household questionnaires, as well as key informant interviews with personnel responsible for street tree planting and maintenance. Sixty-nine out of 300 sampled transects had street trees, with 888 trees enumerated, spanning ninety-seven species. Alien tree species accounted for 71 % of all the enumerated trees while indigenous trees species accounted for 12 %. The non-former homeland towns had a significantly higher (5.8±1.6 trees) mean street tree density per transect than the former homeland towns (0.6±03). There were no significant relationships between street tree density or richness to mean annual rainfall or the background biome in which the town was situated. However, density strongly was related to size of the town. RDP and township suburbs had fewer street trees and low species richness relative to the affluent suburbs. In selecting street trees, root system of the prospective tree, the eventual size or shape of the species, whether an alien or indigenous species, and the species’ adaptability to the climate of the respective town are considered before planting. The biggest identified threats to street trees were the deliberate vandalism of trees by people and animals, and lack of education and awareness regarding the importance of street trees among urban residents and municipal officials. More than half of the respondents prefer that trees be planted both on the street and in their yards while a few do not want trees at all. The majority of respondents with this preference do so because they want shade and abundant fruit, and to have beautiful yards and streets. Those who do not want trees at all do so because they just do not like trees, there is no space for trees, or they fear that criminals hide behind trees. The presence of trees in peoples’ yards correlated with a positive preference for trees in the street. The majority of respondents were neither satisfied with the general appearance of their street nor with the number of trees on their street. Residents from the RDP suburbs were the least satisfied with both the appearance and number of trees on their streets, while those from the affluent suburbs were the most satisfied. Street trees were seen as greatly important to have by the majority of people. The more educated people were more appreciative of the importance of street trees. Local municipalities were identified by the majority of respondents as the stakeholders responsible for the planting and maintenance of street trees, although a considerable proportion of respondents reported a willingness to volunteer to help plant and maintain trees on their streets. Municipalities were seen as doing very little to provide and maintain trees in the various suburbs by the majority of respondents. The majority of respondents also reported that they had never been consulted about tree planting activities in their suburbs before, and would like to have been consulted.
- Full Text:
- Date Issued: 2016
- Authors: Gwedla, Nanamhla
- Date: 2016
- Subjects: Urbanization -- South Africa -- Eastern Cape , Urban ecology (Sociology) -- South Africa -- Eastern Cape , Tree planting -- South Africa -- Eastern Cape , Trees in cities -- Environmental aspects -- South Africa -- Eastern Cape , Urban forestry -- Law and legislation -- South Africa -- Eastern Cape , Low-income housing -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4702 , vital:20714
- Description: Promoting urban sustainability is vital in the face of rapid human and urban population growth. A core tenet of urban sustainability, urban forestry, is poised to “go global” with the intent of mitigating the negative environmental and social effects of urbanisation through green infrastructure, spaces and trees. Amongst these, the planting of street trees has become a major strategy. The public functions of street trees as demonstrated through the provision of ecosystem services are highly dependent on the structure, composition and diversity of tree species within the urban forest. The bulk of available literature on the composition, diversity and perceptions of residents regarding street trees has largely focused on the developed world, while the few in the developing world have been conducted at only one or two sites. The aim of this study was to investigate the composition, diversity and density of urban street trees in relation to the perceptions of local residents and horticulturists, across a range of ecological and social contexts. To do this, the species composition, diversity and dominance of street trees planted in 10 randomly selected Eastern Cape towns was assessed. Within each town ten replicate 200 m transects were located in three different suburbs. Perceptions and appreciation of street trees were assessed by 1 200 household questionnaires, as well as key informant interviews with personnel responsible for street tree planting and maintenance. Sixty-nine out of 300 sampled transects had street trees, with 888 trees enumerated, spanning ninety-seven species. Alien tree species accounted for 71 % of all the enumerated trees while indigenous trees species accounted for 12 %. The non-former homeland towns had a significantly higher (5.8±1.6 trees) mean street tree density per transect than the former homeland towns (0.6±03). There were no significant relationships between street tree density or richness to mean annual rainfall or the background biome in which the town was situated. However, density strongly was related to size of the town. RDP and township suburbs had fewer street trees and low species richness relative to the affluent suburbs. In selecting street trees, root system of the prospective tree, the eventual size or shape of the species, whether an alien or indigenous species, and the species’ adaptability to the climate of the respective town are considered before planting. The biggest identified threats to street trees were the deliberate vandalism of trees by people and animals, and lack of education and awareness regarding the importance of street trees among urban residents and municipal officials. More than half of the respondents prefer that trees be planted both on the street and in their yards while a few do not want trees at all. The majority of respondents with this preference do so because they want shade and abundant fruit, and to have beautiful yards and streets. Those who do not want trees at all do so because they just do not like trees, there is no space for trees, or they fear that criminals hide behind trees. The presence of trees in peoples’ yards correlated with a positive preference for trees in the street. The majority of respondents were neither satisfied with the general appearance of their street nor with the number of trees on their street. Residents from the RDP suburbs were the least satisfied with both the appearance and number of trees on their streets, while those from the affluent suburbs were the most satisfied. Street trees were seen as greatly important to have by the majority of people. The more educated people were more appreciative of the importance of street trees. Local municipalities were identified by the majority of respondents as the stakeholders responsible for the planting and maintenance of street trees, although a considerable proportion of respondents reported a willingness to volunteer to help plant and maintain trees on their streets. Municipalities were seen as doing very little to provide and maintain trees in the various suburbs by the majority of respondents. The majority of respondents also reported that they had never been consulted about tree planting activities in their suburbs before, and would like to have been consulted.
- Full Text:
- Date Issued: 2016
Studies on comparison of aluminium-pillared montmorillonite clay with silica gel on adsorption of methylene blue in waste water
- Authors: Mselana, Sinazo
- Date: 2016
- Subjects: Clay Silica gel Montmorillonite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8011 , vital:31462
- Description: Adsorption equilibrium and kinetics of methylene blue (MB) onto silica gel and aluminum pillared montmorillonite was studied in a batch system. Variables of the system include contact time, salt concentration and initial methylene blue concentration. Langmuir and Freundlich isotherm models were applied to experimental equilibrium data of methylene blue adsorption. Both models were suitable for the parameters. The advantage of silica gel as applied to water treatment is its high porosity when compared to aluminum pillared montmorillonite clay. Water molecules adhere to the silica gels surface because it exhibits a lower vapour pressure than the surrounding air. When equilibrium of equal pressure is reached, no more adsorption occurs. Thus the higher the humidity of the surrounding air, the greater the amount of water that is adsorbed before equilibrium is reached. The increase in pressure loss on the silica gel filters is 1.5 - 2.0 times smaller than in the case of sand filters, Lorenc (2007).
- Full Text:
- Date Issued: 2016
- Authors: Mselana, Sinazo
- Date: 2016
- Subjects: Clay Silica gel Montmorillonite
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8011 , vital:31462
- Description: Adsorption equilibrium and kinetics of methylene blue (MB) onto silica gel and aluminum pillared montmorillonite was studied in a batch system. Variables of the system include contact time, salt concentration and initial methylene blue concentration. Langmuir and Freundlich isotherm models were applied to experimental equilibrium data of methylene blue adsorption. Both models were suitable for the parameters. The advantage of silica gel as applied to water treatment is its high porosity when compared to aluminum pillared montmorillonite clay. Water molecules adhere to the silica gels surface because it exhibits a lower vapour pressure than the surrounding air. When equilibrium of equal pressure is reached, no more adsorption occurs. Thus the higher the humidity of the surrounding air, the greater the amount of water that is adsorbed before equilibrium is reached. The increase in pressure loss on the silica gel filters is 1.5 - 2.0 times smaller than in the case of sand filters, Lorenc (2007).
- Full Text:
- Date Issued: 2016
Study into the synthesis, characterisation and applications of Vanadium-based metal organic frameworks, using 1, 2, 4, 5-benzenetetracarboxylic acid
- Authors: Feldmann, Wesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/55245 , vital:26680
- Description: This study focussed on the synthesis, characterisation and catalytic application of synthesised vanadium-based Metal-Organic Frameworks using 1,2,4,5-benzenetetracarboxylic acid as a ligand. A number of synthetic methods were tested in multiple attempts to synthesise a V-MOF, these included; ambient, gel, reflux and solvothermal methods of synthesis. Two products of interest were identified, an ambient synthesis produced a vanadium-based complex with the empirical formula: V2O2(Na2H2B4C).6H2O (RU-V2) and a solvothermal synthesis produced a MOF with the empirical formula: V2O2(H2O)2(B4C) (RU-V1). Both products were characterised using elemental analysis, infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and X-ray powder diffraction. The catalytic activity of these products was tested, alongside the activity of the solid decavanadate ion, for the conversion of cyclohexene to cyclohexene oxide. The decavanadate ion was included to determine if the ion was catalytically active in the solid state, to potentially be used in the construction of a future MOF or V-complex. The reaction for the conversion of cyclohexene to cyclohexene oxide was chosen, as it has been previously conducted using a V-MOF and was found to be successful. The product of the reaction, the epoxide: cyclohexene oxide, is a very useful precursor for a number of reactions involved in the pharmaceutical industry, so developing catalysts which are able to convert cyclohexene to the epoxide with high yields and selectivities are well sought after in industry. The results of the catalytic reactions were varied, as the materials exhibited high yields and selectivities to the epoxide, but these results were only obtained when water was present in the reaction mixture. Water was able to bring about the cleavage of the bonds between the metal and ligand in a highly coordinated framework, at a faster rate than other solvents, such as decane. This ultimately leads to the structural decomposition of the entire complex or framework, depending upon the reaction time. The use of water was a double edged sword in that it was required to initiate the catalytic reaction, but was also the reason that the catalytic materials were noted to decompose over time. The solid decavanadate ion was only noted to exhibit homogeneous activity by dissolving into the small volume of water present in the reaction mixture. The study proved that using a multidentate ligand such as 1,2,4,5-benzenetetracarboxylic acid yielded products which were highly coordinated in nature and would therefore not have large open spaces associated with them, which is commonly observed with other MOFs. Instead the closed nature of the synthesised complexes and frameworks offered a different environment for catalytic reactions, where the small pores/channels had a controlling and inhibiting effect on the reaction. The conversion of cyclohexene to the epoxide is accompanied with a number of undesired side products, so when using the synthesised closed-natured MOF, it was found that there was a greater selectivity for the epoxide over other potential products. This indicates that close natured MOFs may find application in catalytic reactions which require high selectivities for a particular product.
- Full Text:
- Date Issued: 2016
- Authors: Feldmann, Wesley
- Date: 2016
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/55245 , vital:26680
- Description: This study focussed on the synthesis, characterisation and catalytic application of synthesised vanadium-based Metal-Organic Frameworks using 1,2,4,5-benzenetetracarboxylic acid as a ligand. A number of synthetic methods were tested in multiple attempts to synthesise a V-MOF, these included; ambient, gel, reflux and solvothermal methods of synthesis. Two products of interest were identified, an ambient synthesis produced a vanadium-based complex with the empirical formula: V2O2(Na2H2B4C).6H2O (RU-V2) and a solvothermal synthesis produced a MOF with the empirical formula: V2O2(H2O)2(B4C) (RU-V1). Both products were characterised using elemental analysis, infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and X-ray powder diffraction. The catalytic activity of these products was tested, alongside the activity of the solid decavanadate ion, for the conversion of cyclohexene to cyclohexene oxide. The decavanadate ion was included to determine if the ion was catalytically active in the solid state, to potentially be used in the construction of a future MOF or V-complex. The reaction for the conversion of cyclohexene to cyclohexene oxide was chosen, as it has been previously conducted using a V-MOF and was found to be successful. The product of the reaction, the epoxide: cyclohexene oxide, is a very useful precursor for a number of reactions involved in the pharmaceutical industry, so developing catalysts which are able to convert cyclohexene to the epoxide with high yields and selectivities are well sought after in industry. The results of the catalytic reactions were varied, as the materials exhibited high yields and selectivities to the epoxide, but these results were only obtained when water was present in the reaction mixture. Water was able to bring about the cleavage of the bonds between the metal and ligand in a highly coordinated framework, at a faster rate than other solvents, such as decane. This ultimately leads to the structural decomposition of the entire complex or framework, depending upon the reaction time. The use of water was a double edged sword in that it was required to initiate the catalytic reaction, but was also the reason that the catalytic materials were noted to decompose over time. The solid decavanadate ion was only noted to exhibit homogeneous activity by dissolving into the small volume of water present in the reaction mixture. The study proved that using a multidentate ligand such as 1,2,4,5-benzenetetracarboxylic acid yielded products which were highly coordinated in nature and would therefore not have large open spaces associated with them, which is commonly observed with other MOFs. Instead the closed nature of the synthesised complexes and frameworks offered a different environment for catalytic reactions, where the small pores/channels had a controlling and inhibiting effect on the reaction. The conversion of cyclohexene to the epoxide is accompanied with a number of undesired side products, so when using the synthesised closed-natured MOF, it was found that there was a greater selectivity for the epoxide over other potential products. This indicates that close natured MOFs may find application in catalytic reactions which require high selectivities for a particular product.
- Full Text:
- Date Issued: 2016
Surface characteristics of rock glaciers in the Jutulsessen, Dronning Maud Land, Antarctica
- Rudolph, Elizabeth Magdalena
- Authors: Rudolph, Elizabeth Magdalena
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2667 , vital:20314
- Description: Rock glaciers are landforms that present downslope movement of debris under the influence of ice and gravity. These landforms can be used as paleo-climate indicators as well as proxies for climate change. Rock glaciers have been investigated in a variety of climates and landscapes, however continental Antarctica, Dronning Maud Land specifically, remains understudied. This thesis aimed to investigate and classify five rock glaciers observed in the Jutulsessen, Dronning Maud Land. The surface characteristics and geomorphology were assessed and used as generic classifiers. Size, shape and landscape association was established by field surveying and GIS, whilst sediment and clast characteristics were determined from sampling. A surface temperature profile was created from short-term high frequency temperature measurements. All of the rock glaciers exhibit either undulating surfaces or patterned ground, or both, which suggests active-layer related processes. Sediment particle size analysis is inconclusive. The 137Cs-content and fabric analysis suggest movement regimes similar to other rock glaciers with higher activity at the head, and variable movement directions at the toe. Relative “activeness” is inferred from morphology: Grjotlia, Grjotøyra and Vassdalen were classified as lobate, spatulate and tongue-shaped respectively with Grjotlia the most stable. A new morphological classification of ‘crown-shaped’ is suggested for Brugdedalen and Jutuldalen, and they also appear most active. The control of local climate on rock glacier mechanics is emphasised by the findings, and thus climatic interpolation from a single weather stations is not useful. Increased spatial and temporal coverage of sediment profiles, surface topography and active-layer characteristics could be used to elucidate the processes and controls of these landforms in the Antarctic.
- Full Text:
- Date Issued: 2016
- Authors: Rudolph, Elizabeth Magdalena
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2667 , vital:20314
- Description: Rock glaciers are landforms that present downslope movement of debris under the influence of ice and gravity. These landforms can be used as paleo-climate indicators as well as proxies for climate change. Rock glaciers have been investigated in a variety of climates and landscapes, however continental Antarctica, Dronning Maud Land specifically, remains understudied. This thesis aimed to investigate and classify five rock glaciers observed in the Jutulsessen, Dronning Maud Land. The surface characteristics and geomorphology were assessed and used as generic classifiers. Size, shape and landscape association was established by field surveying and GIS, whilst sediment and clast characteristics were determined from sampling. A surface temperature profile was created from short-term high frequency temperature measurements. All of the rock glaciers exhibit either undulating surfaces or patterned ground, or both, which suggests active-layer related processes. Sediment particle size analysis is inconclusive. The 137Cs-content and fabric analysis suggest movement regimes similar to other rock glaciers with higher activity at the head, and variable movement directions at the toe. Relative “activeness” is inferred from morphology: Grjotlia, Grjotøyra and Vassdalen were classified as lobate, spatulate and tongue-shaped respectively with Grjotlia the most stable. A new morphological classification of ‘crown-shaped’ is suggested for Brugdedalen and Jutuldalen, and they also appear most active. The control of local climate on rock glacier mechanics is emphasised by the findings, and thus climatic interpolation from a single weather stations is not useful. Increased spatial and temporal coverage of sediment profiles, surface topography and active-layer characteristics could be used to elucidate the processes and controls of these landforms in the Antarctic.
- Full Text:
- Date Issued: 2016
Synthesis and characterisation of lanthanide complexes with nitrogen- and oxygen-donor ligands
- Authors: Madanhire, Tatenda
- Date: 2016
- Subjects: Rare earth metals
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13127 , vital:27154
- Description: The reactions of Ln(NO3)3∙6H2O (Ln = Pr, Nd or Er) with the potentially tridentate O,N,O chelating ligand 2,6-pyridinedimethanol (H2pydm) were investigated, and complexes with the formula, [Ln(H2pydm)2(NO3)2](NO3) (Ln = Pr or Nd) and [Er(H2pydm)3](NO3)3 were isolated. The ten-coordinate Pr(III) and Nd(III) compounds crystallise in the triclinic space group P-1 while the nine-coordinate Er(III) complex crystallises in the monoclinic system (P21/n). The reaction of PrCl3∙6H2O with H2pydm yielded the compound, [Pr(H2pydm)3](Cl)3, that crystallises in the monoclinic system, space group P21/c with α = 90, β = 98.680(1) and γ = 90°. The nine-coordinate Pr(III) ion is bound to three H2pydm ligands, with bond distances Pr-O 2.455(2)-2.478(2) Å and Pr-N 2.6355(19)-2.64(2) Å. X-ray crystal structures of all the H2pydm complexes reveal that the ligand coordinates tridentately, via the pyridyl nitrogen atom and the two hydroxyl oxygen atoms. The electronic absorption spectra of complexes show 4f-4f transitions. Rare-earth complexes, [Ln(H2L1)2(NO3)3] [Ln = Gd, Ho or Nd], were also prepared from a Schiff base. The X-ray single-crystal diffraction studies and SHAPE analyses of the Gd(III) and Ho(III) complexes shows that the complexes are ten-coordinate and exhibit distorted tetradecahedron geometries. With proton migration occurring from the phenol group to the imine function, complexation of the lanthanides to the ligand gives the ligand a zwitterionic phenoxo-iminium form. A phenolate oxygen-bridged dinuclear complex, [Ce2(H2L1)(ovan)3(NO3)3], has been obtained by reacting Ce(NO3)3∙6H2O with an o-vanillin derived Schiff base ligand, 2-((E)-(1-hydroxy-2-methylpropan-2-ylimino)methyl)-6-methoxyphenol (H2L1). Hydrolysis of the Schiff base occurred to yield o-vanillin, which bridged two cerium atoms with the Ce∙∙∙Ce distance equal to 3.823 Å. The Ce(III) ions are both tencoordinate, but have different coordination environments, showing tetradecahedron and staggered dodecahedron geometries, respectively. The reaction of salicylaldehyde-N(4)-diethylthiosemicarbazone (H2L2) in the presence of hydrated Ln(III) nitrates led to the isolation of two novel compounds: (E)-2[(ortho-hydroxy)benzylidene]-2-(thiomethyl)-thionohydrazide (1) and bis[2,3-diaza4-(2-hydroxyphenyl)-1-thiomethyl-buta-1,3-diene]disulfide. The latter is a dimer of the former. For this asymmetric Schiff base, 1 and the symmetric disulfide, classical hydrogen bonds of the O–H∙∙∙N as well as N–H∙∙∙S (for 1) type are apparent next to C–H∙∙∙O contacts. 4-(4-Bromophenyl)-1-(propan-2-ylidene)thiosemicarbazide was also prepared upon reacting 4-(4-bromophenyl)-3-thiosemicarbazide with acetone in the presence of ethanol and La(NO3)3∙6H2O. The C=S bond length was found to be 1.6686(16) Å which is in good agreement with other thioketones whose metrical parameters have been deposited with the Cambridge Structural Database. Classical hydrogen bonds of the N–H∙∙∙N and the N–H∙∙∙Br type are observed next to C–H∙∙∙S contacts. All synthesised compounds were characterised by microanalyses, single-crystal X-ray diffraction (except for [Nd(H2L1)2(NO3)3]), 1H NMR and IR spectroscopy.
- Full Text:
- Date Issued: 2016
- Authors: Madanhire, Tatenda
- Date: 2016
- Subjects: Rare earth metals
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13127 , vital:27154
- Description: The reactions of Ln(NO3)3∙6H2O (Ln = Pr, Nd or Er) with the potentially tridentate O,N,O chelating ligand 2,6-pyridinedimethanol (H2pydm) were investigated, and complexes with the formula, [Ln(H2pydm)2(NO3)2](NO3) (Ln = Pr or Nd) and [Er(H2pydm)3](NO3)3 were isolated. The ten-coordinate Pr(III) and Nd(III) compounds crystallise in the triclinic space group P-1 while the nine-coordinate Er(III) complex crystallises in the monoclinic system (P21/n). The reaction of PrCl3∙6H2O with H2pydm yielded the compound, [Pr(H2pydm)3](Cl)3, that crystallises in the monoclinic system, space group P21/c with α = 90, β = 98.680(1) and γ = 90°. The nine-coordinate Pr(III) ion is bound to three H2pydm ligands, with bond distances Pr-O 2.455(2)-2.478(2) Å and Pr-N 2.6355(19)-2.64(2) Å. X-ray crystal structures of all the H2pydm complexes reveal that the ligand coordinates tridentately, via the pyridyl nitrogen atom and the two hydroxyl oxygen atoms. The electronic absorption spectra of complexes show 4f-4f transitions. Rare-earth complexes, [Ln(H2L1)2(NO3)3] [Ln = Gd, Ho or Nd], were also prepared from a Schiff base. The X-ray single-crystal diffraction studies and SHAPE analyses of the Gd(III) and Ho(III) complexes shows that the complexes are ten-coordinate and exhibit distorted tetradecahedron geometries. With proton migration occurring from the phenol group to the imine function, complexation of the lanthanides to the ligand gives the ligand a zwitterionic phenoxo-iminium form. A phenolate oxygen-bridged dinuclear complex, [Ce2(H2L1)(ovan)3(NO3)3], has been obtained by reacting Ce(NO3)3∙6H2O with an o-vanillin derived Schiff base ligand, 2-((E)-(1-hydroxy-2-methylpropan-2-ylimino)methyl)-6-methoxyphenol (H2L1). Hydrolysis of the Schiff base occurred to yield o-vanillin, which bridged two cerium atoms with the Ce∙∙∙Ce distance equal to 3.823 Å. The Ce(III) ions are both tencoordinate, but have different coordination environments, showing tetradecahedron and staggered dodecahedron geometries, respectively. The reaction of salicylaldehyde-N(4)-diethylthiosemicarbazone (H2L2) in the presence of hydrated Ln(III) nitrates led to the isolation of two novel compounds: (E)-2[(ortho-hydroxy)benzylidene]-2-(thiomethyl)-thionohydrazide (1) and bis[2,3-diaza4-(2-hydroxyphenyl)-1-thiomethyl-buta-1,3-diene]disulfide. The latter is a dimer of the former. For this asymmetric Schiff base, 1 and the symmetric disulfide, classical hydrogen bonds of the O–H∙∙∙N as well as N–H∙∙∙S (for 1) type are apparent next to C–H∙∙∙O contacts. 4-(4-Bromophenyl)-1-(propan-2-ylidene)thiosemicarbazide was also prepared upon reacting 4-(4-bromophenyl)-3-thiosemicarbazide with acetone in the presence of ethanol and La(NO3)3∙6H2O. The C=S bond length was found to be 1.6686(16) Å which is in good agreement with other thioketones whose metrical parameters have been deposited with the Cambridge Structural Database. Classical hydrogen bonds of the N–H∙∙∙N and the N–H∙∙∙Br type are observed next to C–H∙∙∙S contacts. All synthesised compounds were characterised by microanalyses, single-crystal X-ray diffraction (except for [Nd(H2L1)2(NO3)3]), 1H NMR and IR spectroscopy.
- Full Text:
- Date Issued: 2016
Synthesis, spectroscopic and nonlinear optical properties of metal-free and nickel β substituted binuclear phthalocyanines
- Authors: Kabwe, Kapambwe Peter
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3013 , vital:20352
- Description: In this project, nickel and metal-free 4β-(4-tert-butylphenoxy) phthalocyanine, biphenyl bridged binuclear 4-tert-butylphenoxy phthalocyanine and naphthalene bridged binuclear 4-tert-butylphenoxy phthalocyanine have been synthesised. The Z-scan technique has been employed to comparatively study their second order nonlinear optical (NLO) properties. This work, shows that the presence of H-aggregation in binuclear Pcs of metal-free and nickel 4β-(4-tertbutylphenoxy) phthalocyanines do not have an effect on the magnitude of second order nonlinear absorption coefficient (β) as compared to monomeric Pcs. Density functional (DFT) calculations of dipolar/octupolar contributions were performed, in order to explain experimentally determined β values. Spectroscopic and photophysical properties of the synthesised compounds have been determined using a range of different spectroscopic techniques, including magnetic circular dichroism (MCD), time correlated single photon counting spectroscopy (TCSPC), UV-visible absorption spectroscopy, mass spectroscopy and IR Spectroscopy.
- Full Text:
- Date Issued: 2016
- Authors: Kabwe, Kapambwe Peter
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3013 , vital:20352
- Description: In this project, nickel and metal-free 4β-(4-tert-butylphenoxy) phthalocyanine, biphenyl bridged binuclear 4-tert-butylphenoxy phthalocyanine and naphthalene bridged binuclear 4-tert-butylphenoxy phthalocyanine have been synthesised. The Z-scan technique has been employed to comparatively study their second order nonlinear optical (NLO) properties. This work, shows that the presence of H-aggregation in binuclear Pcs of metal-free and nickel 4β-(4-tertbutylphenoxy) phthalocyanines do not have an effect on the magnitude of second order nonlinear absorption coefficient (β) as compared to monomeric Pcs. Density functional (DFT) calculations of dipolar/octupolar contributions were performed, in order to explain experimentally determined β values. Spectroscopic and photophysical properties of the synthesised compounds have been determined using a range of different spectroscopic techniques, including magnetic circular dichroism (MCD), time correlated single photon counting spectroscopy (TCSPC), UV-visible absorption spectroscopy, mass spectroscopy and IR Spectroscopy.
- Full Text:
- Date Issued: 2016
Technical and institutional constraints faced by vegetable co-operatives in the Buffalo City Metropolitan Municipality in Eastern Cape Province, South Africa
- Authors: Madlodlo, Sinazo
- Date: 2016
- Subjects: Agriculture, Cooperative -- South Africa -- Eastern Cape , Vegetable trade -- South Africa -- Eastern Cape , Cooperative marketing of farm produce -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1497 , vital:27396
- Description: This study focused on the technical and institutional constraints faced by the vegetable co-operatives with regard to the impact on productivity. Vegetable co-operatives have no access to markets due to their poor performance on productivity and poor quality produce resulting to low prices for the produce such that they cannot compete in a market economy. In this study, the data was drawn from a sample of thirty vegetable co-operatives in the Buffalo City Metropolitan Municipality (BCMM) of the Eastern Cape; obtained through focus group discussions and interviews from each cooperative. The objectives of the study are to measure the productivity of vegetable co-operatives using Total factor productivity analysis (TFP) and profitability of vegetable co-operative using Gross Margin (GM). Followed by the descriptive statistics in identifying and assessing the socio-economic characteristics as well as coping strategies adopted by vegetable co-operatives in BCMM where percentages, means and tables are used looking at the highest frequency. The results show that the vegetable co-operatives in the BCMM are not productive and profitable due to major constraints experienced by co-operatives such as lack of market, information, trainings and business skills, capital, infrastructural facilities, effective extension services that all leads to poor produce quality. Co-operative is said to be profitable and viable if total revenue is greater than the total variable cost which makes the gross margin positive. In this case, the total gross margin is negative. The results showed that the production costs, maintenance (tractor hire, generator hire and servicing) and electricity costs were the major costs incurred in the production of vegetable by the co-operatives.
- Full Text:
- Date Issued: 2016
- Authors: Madlodlo, Sinazo
- Date: 2016
- Subjects: Agriculture, Cooperative -- South Africa -- Eastern Cape , Vegetable trade -- South Africa -- Eastern Cape , Cooperative marketing of farm produce -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1497 , vital:27396
- Description: This study focused on the technical and institutional constraints faced by the vegetable co-operatives with regard to the impact on productivity. Vegetable co-operatives have no access to markets due to their poor performance on productivity and poor quality produce resulting to low prices for the produce such that they cannot compete in a market economy. In this study, the data was drawn from a sample of thirty vegetable co-operatives in the Buffalo City Metropolitan Municipality (BCMM) of the Eastern Cape; obtained through focus group discussions and interviews from each cooperative. The objectives of the study are to measure the productivity of vegetable co-operatives using Total factor productivity analysis (TFP) and profitability of vegetable co-operative using Gross Margin (GM). Followed by the descriptive statistics in identifying and assessing the socio-economic characteristics as well as coping strategies adopted by vegetable co-operatives in BCMM where percentages, means and tables are used looking at the highest frequency. The results show that the vegetable co-operatives in the BCMM are not productive and profitable due to major constraints experienced by co-operatives such as lack of market, information, trainings and business skills, capital, infrastructural facilities, effective extension services that all leads to poor produce quality. Co-operative is said to be profitable and viable if total revenue is greater than the total variable cost which makes the gross margin positive. In this case, the total gross margin is negative. The results showed that the production costs, maintenance (tractor hire, generator hire and servicing) and electricity costs were the major costs incurred in the production of vegetable by the co-operatives.
- Full Text:
- Date Issued: 2016
Testing the effectiveness and cost-efficiency of livestock guarding dogs in Botswana
- Authors: Horgan, Jane Elizabeth
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5951 , http://hdl.handle.net/10962/d1021300
- Description: Livestock guarding dogs (LSGDs) have been used for centuries to reduce depredation on livestock and more recently, to facilitate the conservation of threatened predator species. Conservation NGOs (non-government organisations) in southern Africa promote the use of Anatolian Shepherds as LSGDs. However, livestock farmers in Botswana have been using a variety of different breeds for this purpose, including the local mixed-breed “Tswana” dogs. Postal, telephonic and face-to-face interview questionnaires were administered to 108 livestock farmers in Botswana to gauge how their LSGDs were being used, in order to determine what factors contributed to the success and affordability of these dogs. Eighty-three percent of farmers had LSGDs which equaled or decreased livestock depredations on their farms, with an average reduction in livestock depredation of 75% per year. This equated to an average saving of US$2,017 annually per farm. The costs of purchasing (average US$27) and maintaining the 198 LSGDs in my study (average US$169/LSGD/year) were very low compared to other countries and helped contribute to the high profits obtained by farmers (average US$1,497/farm or US$789/LSGD). A unique investigation of different breeds was possible due to the diverse array of breeds in the sample (Anatolian Shepherds, Cross Breeds, Tswana dogs, Greyhounds and Pitbulls), with the crossbreed dogs (Crosses and Tswana LSGDs) performing the best. LSGDs that reduced depredation and had minimal behavioural problems were the most likely to incite positive changes in their owners in regards to attitudes towards predators. Sixtysix percent of farmers stated that they were more tolerant of predators since obtaining a LSGD, and 51% reported that they were less likely to kill predators since obtaining a LSGD. My results indicate that successful, well-behaved LSGDs are a cost-effective tool that has the ability to increase farm productivity and improve predator-farmer conflicts in Botswana. The methods recommended in my thesis, in particular the benefits of using local breeds of dog as LSGDs, can be implemented on farming practices the world over to assist farming productivity and to promote conservation efforts.
- Full Text:
- Date Issued: 2016
- Authors: Horgan, Jane Elizabeth
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5951 , http://hdl.handle.net/10962/d1021300
- Description: Livestock guarding dogs (LSGDs) have been used for centuries to reduce depredation on livestock and more recently, to facilitate the conservation of threatened predator species. Conservation NGOs (non-government organisations) in southern Africa promote the use of Anatolian Shepherds as LSGDs. However, livestock farmers in Botswana have been using a variety of different breeds for this purpose, including the local mixed-breed “Tswana” dogs. Postal, telephonic and face-to-face interview questionnaires were administered to 108 livestock farmers in Botswana to gauge how their LSGDs were being used, in order to determine what factors contributed to the success and affordability of these dogs. Eighty-three percent of farmers had LSGDs which equaled or decreased livestock depredations on their farms, with an average reduction in livestock depredation of 75% per year. This equated to an average saving of US$2,017 annually per farm. The costs of purchasing (average US$27) and maintaining the 198 LSGDs in my study (average US$169/LSGD/year) were very low compared to other countries and helped contribute to the high profits obtained by farmers (average US$1,497/farm or US$789/LSGD). A unique investigation of different breeds was possible due to the diverse array of breeds in the sample (Anatolian Shepherds, Cross Breeds, Tswana dogs, Greyhounds and Pitbulls), with the crossbreed dogs (Crosses and Tswana LSGDs) performing the best. LSGDs that reduced depredation and had minimal behavioural problems were the most likely to incite positive changes in their owners in regards to attitudes towards predators. Sixtysix percent of farmers stated that they were more tolerant of predators since obtaining a LSGD, and 51% reported that they were less likely to kill predators since obtaining a LSGD. My results indicate that successful, well-behaved LSGDs are a cost-effective tool that has the ability to increase farm productivity and improve predator-farmer conflicts in Botswana. The methods recommended in my thesis, in particular the benefits of using local breeds of dog as LSGDs, can be implemented on farming practices the world over to assist farming productivity and to promote conservation efforts.
- Full Text:
- Date Issued: 2016
The adequacy of traffic control measures during road works
- Authors: Norris, Shaun Peter
- Date: 2016
- Subjects: Roads -- Safety measures Roads -- Maintenance and repair Construction industry -- Employees -- Health and hygiene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/11520 , vital:26934
- Description: Workers have the right to a safe working environment. This right is encapsulated in the Bill of Rights (1996) wherein strong emphasis is placed on the right to a healthy and safe work environment. The construction industry has been labeled as dangerous owing to regular incidents, serious accidents, and fatalities. Road workers’ safety is at high risk in road construction areas, as they perform their work activities alongside moving vehicles that are often large and sometimes moving at high speed. It was determined that very few secondary sources provided information regarding the safety of South African road construction workers. Therefore, the knowledge obtained from this study contributes to the body of knowledge on the subject matter. To collect data, three descriptive surveys were conducted on two different road construction projects within the Eastern Cape. The survey participants included engineering consultants, contractors, traffic safety officers, general road construction workers, as well as random motorists driving through the work zone. Further data was collected from a speed measuring instrument placed in the work zone of the Port Elizabeth. The findings of this research report indicate that road users are not cognizant of the risk to workers in the work zone and that signage and advance warning signs alone are not sufficient to slow motorists’ speed. A further significant threat to road worker safety, is plant operator visibility. This study recommends that government and construction firms educate the public regarding the risks associated with speeding through a work zone. Construction firms should use electronic speed measuring devices prior to the work zone to make road users aware of their speed in relation to the speed limit. To limit plant related accidents, companies should install sensors or cameras on the rear and side panels of plant, so that plant operators have all round vision. Furthermore, road workers could be educated on the controlled use of their mobile phones to reduce the risks associated with the use of mobile phones inside work zones.
- Full Text:
- Date Issued: 2016
- Authors: Norris, Shaun Peter
- Date: 2016
- Subjects: Roads -- Safety measures Roads -- Maintenance and repair Construction industry -- Employees -- Health and hygiene
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/11520 , vital:26934
- Description: Workers have the right to a safe working environment. This right is encapsulated in the Bill of Rights (1996) wherein strong emphasis is placed on the right to a healthy and safe work environment. The construction industry has been labeled as dangerous owing to regular incidents, serious accidents, and fatalities. Road workers’ safety is at high risk in road construction areas, as they perform their work activities alongside moving vehicles that are often large and sometimes moving at high speed. It was determined that very few secondary sources provided information regarding the safety of South African road construction workers. Therefore, the knowledge obtained from this study contributes to the body of knowledge on the subject matter. To collect data, three descriptive surveys were conducted on two different road construction projects within the Eastern Cape. The survey participants included engineering consultants, contractors, traffic safety officers, general road construction workers, as well as random motorists driving through the work zone. Further data was collected from a speed measuring instrument placed in the work zone of the Port Elizabeth. The findings of this research report indicate that road users are not cognizant of the risk to workers in the work zone and that signage and advance warning signs alone are not sufficient to slow motorists’ speed. A further significant threat to road worker safety, is plant operator visibility. This study recommends that government and construction firms educate the public regarding the risks associated with speeding through a work zone. Construction firms should use electronic speed measuring devices prior to the work zone to make road users aware of their speed in relation to the speed limit. To limit plant related accidents, companies should install sensors or cameras on the rear and side panels of plant, so that plant operators have all round vision. Furthermore, road workers could be educated on the controlled use of their mobile phones to reduce the risks associated with the use of mobile phones inside work zones.
- Full Text:
- Date Issued: 2016
The application of GIS and remote sensing to assess the effect of periodic flooding on communities along the Juskeiriver: A case study of Alexandria Township, Johannesburg, South Africa
- Authors: Mawasha, Tshepo Sylvester
- Date: 2016
- Subjects: Remote sensing Geographic information systems -- South Africa , Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/45613 , vital:38918
- Description: Floods are water induced disasters that led to temporary induction of dry and cause serious damages in the affected location such as loss of valuable assets, lives and destruction of infrastructure. Flooding had become common in Alexandra Township during rainfall season and the recorded impact of periodic flooding on communities is increasing at an alarming rate. This study seeks to identify populations vulnerable to flooding and to map-out areas at high risk of flood disasters, using GIS and RS as a tool. For GIS application different types of maps were produced, namely, flood vulnerability, hazards, risk and risk index map highlighting areas at risk of being affected by flooding. Flood risk index maps identify three categories of risk zones; low and high risk zone. The household units within each of the risk zones was calculated and the total was estimated to be 762 for low-risk and 32 486 for high risk zone. The SRTM Digital Elevation Model (DEM) and multi-temporal Satellite Probatoire d’Observation de la Terra (SPOT) satellite images for 1997, 2006 and 2013 of the area was used for land-use and land-cover (LULC) change analyses using maximum-likelihood post-classification comparison. Results reveal that tremendous urban development had taken place in the study area along the Jukskei River area for the past sixteen years. It was observed that there was a sharp decrease in vegetation from 237ha (1997) to 134ha (2006) to 68ha (2013). This may had a negative impact on the environment around this area by decreasing surface runoff. The trend however, shows that bare surface and vegetation land-cover class has no potential to recover. Questionnaires aimed at all the residents in the study area were used to assess the effect of periodic flooding on communities. Community leader and City of Johannesburg Disaster Management Unit (CoJDMU) interviews were also conducted to get more insight about floods management in the study area. Finally, strategies for alleviating flood risk in the study area were discussed and some recommendations were made to help the government and municipal authorities to improve and development sustainable flood mitigation measures.
- Full Text:
- Date Issued: 2016
- Authors: Mawasha, Tshepo Sylvester
- Date: 2016
- Subjects: Remote sensing Geographic information systems -- South Africa , Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/45613 , vital:38918
- Description: Floods are water induced disasters that led to temporary induction of dry and cause serious damages in the affected location such as loss of valuable assets, lives and destruction of infrastructure. Flooding had become common in Alexandra Township during rainfall season and the recorded impact of periodic flooding on communities is increasing at an alarming rate. This study seeks to identify populations vulnerable to flooding and to map-out areas at high risk of flood disasters, using GIS and RS as a tool. For GIS application different types of maps were produced, namely, flood vulnerability, hazards, risk and risk index map highlighting areas at risk of being affected by flooding. Flood risk index maps identify three categories of risk zones; low and high risk zone. The household units within each of the risk zones was calculated and the total was estimated to be 762 for low-risk and 32 486 for high risk zone. The SRTM Digital Elevation Model (DEM) and multi-temporal Satellite Probatoire d’Observation de la Terra (SPOT) satellite images for 1997, 2006 and 2013 of the area was used for land-use and land-cover (LULC) change analyses using maximum-likelihood post-classification comparison. Results reveal that tremendous urban development had taken place in the study area along the Jukskei River area for the past sixteen years. It was observed that there was a sharp decrease in vegetation from 237ha (1997) to 134ha (2006) to 68ha (2013). This may had a negative impact on the environment around this area by decreasing surface runoff. The trend however, shows that bare surface and vegetation land-cover class has no potential to recover. Questionnaires aimed at all the residents in the study area were used to assess the effect of periodic flooding on communities. Community leader and City of Johannesburg Disaster Management Unit (CoJDMU) interviews were also conducted to get more insight about floods management in the study area. Finally, strategies for alleviating flood risk in the study area were discussed and some recommendations were made to help the government and municipal authorities to improve and development sustainable flood mitigation measures.
- Full Text:
- Date Issued: 2016
The biomass production, nutrient content and silage quality of Perennial ryegrass (Lolium perenne (L)) Cocksfoot (Dactylis glomerata (L)) and Tall fescue (Festuca arundinacea (Schreb)) varieties grown under irrigation in Alice, South Africa
- Authors: Tikwayo, Sizwe Edward
- Date: 2016
- Subjects: Ryegrasses -- Varieties -- South Africa -- Eastern Cape Ryegrasses -- Irrigation -- South Africa -- Eastern Cape Biomass energy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1796 , vital:27560
- Description: The study aims to evaluate the biomass production and nutrient content and silage quality of perennial ryegrass (Lolium perenne (L)), cocksfoot (Dactylis glomerata (L)) and tall fescue (Festuca arundinacea (Schreb)). Six varieties were used, two for each species. A completely randomized block designed replicated three times was conducted at University of Fort Hare Research Farm during 2014-2015 growing season. The plots were harvested at four-week interval (post emergency) for one year. Biomass yields were measured for fresh forage and dry matter yield. Duplicated samples were then dried, milled and analyzed for chemical and mineral composition (CP, NDF, ADF, and ash, Ca, P, K, Na, Mn, Cu, Zn and Fe) for only winter season. In addition the grasses were ensiled and the silage was analyzed for its fermentation parameters and nutrient content (lactic acid, pH, DM, CP, NDF, ADF, and ash, Ca, P, K, Na, Mn, Cu, Zn and Fe). Biomass results showed significant differences (P < 0.05) between season and varieties. On average Tall fescue varieties Jessup (13741.67 FM kg/ha), Alix (12007.78 FM kg/ ha) and Ryegrass varieties Samson (11597.22 FM kg/ha) and Nui (10591.67 FM kg/ha) had the highest fresh biomass yield. Similarly, Tall fescue varieties Jessup (2833.06 DM kg/ha) and Alix (2708.3 DM kg/ ha) and Ryegrass varieties Samson (2169.44 DM kg/ha) and Nui (2169.67 kg/ha) had the highest dry biomass yield. Throughout the year the average biomass yield was significantly different among species (P< 0.05). During summer and autumn Tall fescue varieties Jessup and Alix gave the highest dry matter yields of 3855.5 to 1977.8 DM kg/ha, and 3877.8 to 1900 DM kg/ha, respectively, and followed by Cocksfoot 2400 DM kg/ha. Ryegrass had the highest dry matter biomass yield in winter (2975 DM kg/ha) and the least in summer (977.75 DM kg/ha). There were no significant (P>0.05) differences on the chemical composition (CP, NDF, ADF, and ash) and mineral composition (Ca, P, K, Na, Mn, Cu, Zn and Fe) of the six varieties. The grass silage results showed significant differences (P< 0.05) among the six varieties for moisture content. Perennial ryegrass variety Nui (66.76 percent) had low moisture content than the other grass silages. The different varieties had no significant effects (P>0.05) on chemical composition (CP, NDF, ADF, and ash) and mineral composition (Ca, P, K, Na, Mn, Cu, Zn and Fe). It is concluded that the biomass production of the six varieties of three grass species was different throughout the year under irrigation hence Ryegrass and Tall fescue are recommended for dairy farmers in the region for all seasons. It can be concluded that there is no difference with respect to fermentation characteristics and nutrient content among the varieties of the grass species.
- Full Text:
- Date Issued: 2016
- Authors: Tikwayo, Sizwe Edward
- Date: 2016
- Subjects: Ryegrasses -- Varieties -- South Africa -- Eastern Cape Ryegrasses -- Irrigation -- South Africa -- Eastern Cape Biomass energy -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1796 , vital:27560
- Description: The study aims to evaluate the biomass production and nutrient content and silage quality of perennial ryegrass (Lolium perenne (L)), cocksfoot (Dactylis glomerata (L)) and tall fescue (Festuca arundinacea (Schreb)). Six varieties were used, two for each species. A completely randomized block designed replicated three times was conducted at University of Fort Hare Research Farm during 2014-2015 growing season. The plots were harvested at four-week interval (post emergency) for one year. Biomass yields were measured for fresh forage and dry matter yield. Duplicated samples were then dried, milled and analyzed for chemical and mineral composition (CP, NDF, ADF, and ash, Ca, P, K, Na, Mn, Cu, Zn and Fe) for only winter season. In addition the grasses were ensiled and the silage was analyzed for its fermentation parameters and nutrient content (lactic acid, pH, DM, CP, NDF, ADF, and ash, Ca, P, K, Na, Mn, Cu, Zn and Fe). Biomass results showed significant differences (P < 0.05) between season and varieties. On average Tall fescue varieties Jessup (13741.67 FM kg/ha), Alix (12007.78 FM kg/ ha) and Ryegrass varieties Samson (11597.22 FM kg/ha) and Nui (10591.67 FM kg/ha) had the highest fresh biomass yield. Similarly, Tall fescue varieties Jessup (2833.06 DM kg/ha) and Alix (2708.3 DM kg/ ha) and Ryegrass varieties Samson (2169.44 DM kg/ha) and Nui (2169.67 kg/ha) had the highest dry biomass yield. Throughout the year the average biomass yield was significantly different among species (P< 0.05). During summer and autumn Tall fescue varieties Jessup and Alix gave the highest dry matter yields of 3855.5 to 1977.8 DM kg/ha, and 3877.8 to 1900 DM kg/ha, respectively, and followed by Cocksfoot 2400 DM kg/ha. Ryegrass had the highest dry matter biomass yield in winter (2975 DM kg/ha) and the least in summer (977.75 DM kg/ha). There were no significant (P>0.05) differences on the chemical composition (CP, NDF, ADF, and ash) and mineral composition (Ca, P, K, Na, Mn, Cu, Zn and Fe) of the six varieties. The grass silage results showed significant differences (P< 0.05) among the six varieties for moisture content. Perennial ryegrass variety Nui (66.76 percent) had low moisture content than the other grass silages. The different varieties had no significant effects (P>0.05) on chemical composition (CP, NDF, ADF, and ash) and mineral composition (Ca, P, K, Na, Mn, Cu, Zn and Fe). It is concluded that the biomass production of the six varieties of three grass species was different throughout the year under irrigation hence Ryegrass and Tall fescue are recommended for dairy farmers in the region for all seasons. It can be concluded that there is no difference with respect to fermentation characteristics and nutrient content among the varieties of the grass species.
- Full Text:
- Date Issued: 2016
The characterization of and formulation development using a novel tyre devulcanizate
- von Berg, Stuart, Hlangothi, Percy
- Authors: von Berg, Stuart , Hlangothi, Percy
- Date: 2016
- Subjects: Rubber, Reclaimed Rubber chemicals Tires -- Recycling
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13149 , vital:27156
- Description: The amount of waste tyres being dumped is fast becoming a problem. These stockpiles take up valuable land and are an environmental and health problem. While incineration is the simplest way to recycle the used tyres it isn’t an efficient way to dispose of tyres. This research looks at developing a method for characterizing the New Reclamation Group (NRG) reclaim with the main focus on Hi-Res™ thermogravimetric analysis. Good quantification was possible using this technique. A trade off was established between resolution, sensitivity and time. While increasing the resolution allowed greater separation to be achieved the time for each experiment increased rapidly. Although kinetic models do exist for quantifying rubber components in vulcanized sample, they were not suitable for this study. When devulcanization causes significant molecular changes, such as with NRG reclaim, the decomposition profiles no longer match those of virgin materials. Formulations developed focused on mixing, rheometry, crosslink density and tensile properties. The NRG reclaim acted as a processing aid which lowered the maximum torque. This provides mixing safety as the temperature is decreased as a result of the lower torque. This effect was not seen with conventional reclaim. Rheometry tests indicated that the addition of the devulcanizates decreased the extent of cure. It was demonstrated that this could be linked to crosslink density. Testing of the 100%, 200%, 300% moduli correlated the crosslink density to the maximum torque. Although the addition of NRG reclaim reduced the tensile strength of the formulation, a link between crosslink density and ultimate tensile strength (UTS) couldn’t be made. The decrease in the UTS and increase in extension at break is possibly caused by an increase in low molecular weight material present in the formulations and decrease in crosslink density. This could possibly increase the mobility of polymer chains which could increases flexibility.
- Full Text:
- Date Issued: 2016
- Authors: von Berg, Stuart , Hlangothi, Percy
- Date: 2016
- Subjects: Rubber, Reclaimed Rubber chemicals Tires -- Recycling
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/13149 , vital:27156
- Description: The amount of waste tyres being dumped is fast becoming a problem. These stockpiles take up valuable land and are an environmental and health problem. While incineration is the simplest way to recycle the used tyres it isn’t an efficient way to dispose of tyres. This research looks at developing a method for characterizing the New Reclamation Group (NRG) reclaim with the main focus on Hi-Res™ thermogravimetric analysis. Good quantification was possible using this technique. A trade off was established between resolution, sensitivity and time. While increasing the resolution allowed greater separation to be achieved the time for each experiment increased rapidly. Although kinetic models do exist for quantifying rubber components in vulcanized sample, they were not suitable for this study. When devulcanization causes significant molecular changes, such as with NRG reclaim, the decomposition profiles no longer match those of virgin materials. Formulations developed focused on mixing, rheometry, crosslink density and tensile properties. The NRG reclaim acted as a processing aid which lowered the maximum torque. This provides mixing safety as the temperature is decreased as a result of the lower torque. This effect was not seen with conventional reclaim. Rheometry tests indicated that the addition of the devulcanizates decreased the extent of cure. It was demonstrated that this could be linked to crosslink density. Testing of the 100%, 200%, 300% moduli correlated the crosslink density to the maximum torque. Although the addition of NRG reclaim reduced the tensile strength of the formulation, a link between crosslink density and ultimate tensile strength (UTS) couldn’t be made. The decrease in the UTS and increase in extension at break is possibly caused by an increase in low molecular weight material present in the formulations and decrease in crosslink density. This could possibly increase the mobility of polymer chains which could increases flexibility.
- Full Text:
- Date Issued: 2016
The classsification of fuzzy subgroups of some finite Abelian p-groups of rank 3
- Authors: Appiah, Isaac Kwadwo
- Date: 2016
- Subjects: Fuzzy sets Abelian groups Finite groups
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2468 , vital:27845
- Description: An important trend in fuzzy group theory in recent years has been the notion of classification of fuzzy subgroups using a suitable equivalence relation. In this dissertation, we have successfully used the natural equivalence relation defined by Murali and Makamba in [81] and a natural fuzzy isomorphism to classify fuzzy subgroups of some finite abelian p-groups of rank three of the form Zpn + Zp + Zp for any fixed prime integer p and any positive integer n. This was achieved through the usage of a suitable technique of enumerating distinct fuzzy subgroups and non-isomorphic fuzzy subgroups of G. We commence by giving a brief discussion on the theory of fuzzy sets and fuzzy subgroups from the perspective of group theory through to the theory of sets, leading us to establish a linkage among these theories. We have also shown in this dissertation that the converse of theorem 3.1 proposed by Das in [24] is incorrect by giving a counter example and restate the theorem. We have then reviewed and enriched the study conducted by Ngcibi in [94] by characterising the non-isomorphic fuzzy subgroups in that study. We have also developed a formula to compute the crisp subgroups of the under-studied group and provide its proof. Furthermore, we have compared the equivalence relation under which the classification problem is based with various versions of equivalence studied in the literature. We managed to use this counting technique to obtain explicit formulae for the number of maximal chains, distinct fuzzy subgroups, non-isomorphic maximal chains and non-isomorphic fuzzy subgroups of these groups and their proofs are provided.
- Full Text:
- Date Issued: 2016
- Authors: Appiah, Isaac Kwadwo
- Date: 2016
- Subjects: Fuzzy sets Abelian groups Finite groups
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2468 , vital:27845
- Description: An important trend in fuzzy group theory in recent years has been the notion of classification of fuzzy subgroups using a suitable equivalence relation. In this dissertation, we have successfully used the natural equivalence relation defined by Murali and Makamba in [81] and a natural fuzzy isomorphism to classify fuzzy subgroups of some finite abelian p-groups of rank three of the form Zpn + Zp + Zp for any fixed prime integer p and any positive integer n. This was achieved through the usage of a suitable technique of enumerating distinct fuzzy subgroups and non-isomorphic fuzzy subgroups of G. We commence by giving a brief discussion on the theory of fuzzy sets and fuzzy subgroups from the perspective of group theory through to the theory of sets, leading us to establish a linkage among these theories. We have also shown in this dissertation that the converse of theorem 3.1 proposed by Das in [24] is incorrect by giving a counter example and restate the theorem. We have then reviewed and enriched the study conducted by Ngcibi in [94] by characterising the non-isomorphic fuzzy subgroups in that study. We have also developed a formula to compute the crisp subgroups of the under-studied group and provide its proof. Furthermore, we have compared the equivalence relation under which the classification problem is based with various versions of equivalence studied in the literature. We managed to use this counting technique to obtain explicit formulae for the number of maximal chains, distinct fuzzy subgroups, non-isomorphic maximal chains and non-isomorphic fuzzy subgroups of these groups and their proofs are provided.
- Full Text:
- Date Issued: 2016