The biology of suburban olive thrushes (Turdus olivaceus olivaceus) in the Eastern Cape, South Africa
- Authors: Bonnevie, Bo Tørris
- Date: 2005
- Subjects: Thrushes , Turdus , Thrushes -- South Africa -- Eastern Cape , Turdus -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5651 , http://hdl.handle.net/10962/d1005333 , Thrushes , Turdus , Thrushes -- South Africa -- Eastern Cape , Turdus -- South Africa -- Eastern Cape
- Description: This study investigated the biology of the Olive Thrush Turdus olivaceus olivaceus in Grahamstown, South Africa from 1998 to 2003. Behavioural differences between males and females, parent-young interactions, development of fledglings, and the role of song and moult in territorial behaviour were investigated. Comparisons of biometrics, moult and survival were made using Olive Thrush ringing data from other regions. There were no significant differences in mass, wing length or survival rate between the Eastern and Western Cape provinces, but primary wing moult started earlier in the Western Cape and coincided with the end of the main breeding periods in both provinces. Both males and females of breeding pairs remained in and defended their territories throughout the year, but there was some evidence that territorial defence was strongest during the breeding periods. Roughly, every 100 eggs laid produce 50 fledglings. Out of these 20 to 30 reach the age of independence at approximately 50 days, and only five of these juvenile birds reach maturity. Adult survival was estimated at 80%, with a mean life expectancy of 4.5 years and a conservative estimate of maximum lifespan of 11 years. Using ringing data and museum specimens, the Olive Thrush was compared with the Karoo Thrush Turdus smithi, a former race of the Olive Thrush. Olive Thrushes had shorter bills and wings, but were heavier than Karoo Thrushes from the Cradock district. There were also differences in bill and eye-ring colouration between these populations. No morphological differences were found between the sexes in either species.
- Full Text:
- Date Issued: 2005
- Authors: Bonnevie, Bo Tørris
- Date: 2005
- Subjects: Thrushes , Turdus , Thrushes -- South Africa -- Eastern Cape , Turdus -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5651 , http://hdl.handle.net/10962/d1005333 , Thrushes , Turdus , Thrushes -- South Africa -- Eastern Cape , Turdus -- South Africa -- Eastern Cape
- Description: This study investigated the biology of the Olive Thrush Turdus olivaceus olivaceus in Grahamstown, South Africa from 1998 to 2003. Behavioural differences between males and females, parent-young interactions, development of fledglings, and the role of song and moult in territorial behaviour were investigated. Comparisons of biometrics, moult and survival were made using Olive Thrush ringing data from other regions. There were no significant differences in mass, wing length or survival rate between the Eastern and Western Cape provinces, but primary wing moult started earlier in the Western Cape and coincided with the end of the main breeding periods in both provinces. Both males and females of breeding pairs remained in and defended their territories throughout the year, but there was some evidence that territorial defence was strongest during the breeding periods. Roughly, every 100 eggs laid produce 50 fledglings. Out of these 20 to 30 reach the age of independence at approximately 50 days, and only five of these juvenile birds reach maturity. Adult survival was estimated at 80%, with a mean life expectancy of 4.5 years and a conservative estimate of maximum lifespan of 11 years. Using ringing data and museum specimens, the Olive Thrush was compared with the Karoo Thrush Turdus smithi, a former race of the Olive Thrush. Olive Thrushes had shorter bills and wings, but were heavier than Karoo Thrushes from the Cradock district. There were also differences in bill and eye-ring colouration between these populations. No morphological differences were found between the sexes in either species.
- Full Text:
- Date Issued: 2005
A study of plocamium corallorhiza secondary metabolites and their biological activity
- Authors: Mkwananzi, Henry Bayanda
- Date: 2005
- Subjects: Natural products -- Therapeutic use , Marine metabolites -- Therapeutic use , Marine pharmacology , Marine algae , Monoterpenes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3841 , http://hdl.handle.net/10962/d1007666 , Natural products -- Therapeutic use , Marine metabolites -- Therapeutic use , Marine pharmacology , Marine algae , Monoterpenes
- Description: Seaweeds of the genus Plocamium are known to produce a variety of halogenated monoterpenes. In addition to their ecological role as feeding deterrents, biological activities reported for these compounds include antibacterial, antialgal, antifungal and anticancer activities. An investigation of the non-polar extracts of the seaweed Plocamium corallorhiza resulted in the isolation of six known halogenated monoterpene compounds, 4-bromo-5-bromomethyl-1-chlorovinyl-2, 5-dichloro-methylcyclohexane (2.68), 1,4,8-tribromo-3 ,7-dichloro-3, 7-dimethyl-1,5-octadiene (2.67), 8-bromo-1 ,3,4,7-tetrachloro-3, 7-dimethyl-1,5-octadiene (2.66), 4,6-dibromo-1,1-dichloro-3,7-dimethyl-2,7-octadiene (2.64), 4,8-dibromo-1,1,7-trichloro-3,7-dimethyl-2,5-octadiene (2.65) and 3,4 ,6,7-tetrachloro-3, 7-dimethyl-1-octene (2.63) as well as eight new compounds, including five halogenated monoterpene aldehydes. The new compounds were identified by 1D and 2D NMR spectroscopic techniques as: 8-Bromo-6,7-dichloro-3,7-dimethyl-octa-2,4-dienal (2.72), 8-Bromo-1,1,2,7-tetrachloro-3,7-dimethyl-octa-3,5-diene (2.70), 4,8-Dichloro-3,7-dimethyl-octa-2,4,6-trienal (2.74), 4-Bromo-8-chloro-3, 7-di methyl-octa-2, 6-dienal (2 76), 8-Bromo-4-chloro-3, 7-dimethyl-octa-2,4 ,6-trienaI (2.75), 4-Bromo-1,3,6,7-tetrachloro-3 ,7-dimethyl-octa-1,4-diene (2.71), 8-Bromo-1,3,4,7-tetrachloro-3,7-dimethyl-octa-1,5-diene (2.69), 4,6-Dibromo-3,7 -dimethyl-octa-2,7-dienal (2.73). All compounds were screened for antimicrobial activity, brine shrimp lethality and cytotoxicity towards oesophageal cancer cells. Compound 2.68 was toxic to brine shrimp larvae at a concentration of 50 μ/mL. It also showed promising activity towards oesophageal cancer cells with an IC₅₀, of 2 μg/mL.
- Full Text:
- Date Issued: 2005
- Authors: Mkwananzi, Henry Bayanda
- Date: 2005
- Subjects: Natural products -- Therapeutic use , Marine metabolites -- Therapeutic use , Marine pharmacology , Marine algae , Monoterpenes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3841 , http://hdl.handle.net/10962/d1007666 , Natural products -- Therapeutic use , Marine metabolites -- Therapeutic use , Marine pharmacology , Marine algae , Monoterpenes
- Description: Seaweeds of the genus Plocamium are known to produce a variety of halogenated monoterpenes. In addition to their ecological role as feeding deterrents, biological activities reported for these compounds include antibacterial, antialgal, antifungal and anticancer activities. An investigation of the non-polar extracts of the seaweed Plocamium corallorhiza resulted in the isolation of six known halogenated monoterpene compounds, 4-bromo-5-bromomethyl-1-chlorovinyl-2, 5-dichloro-methylcyclohexane (2.68), 1,4,8-tribromo-3 ,7-dichloro-3, 7-dimethyl-1,5-octadiene (2.67), 8-bromo-1 ,3,4,7-tetrachloro-3, 7-dimethyl-1,5-octadiene (2.66), 4,6-dibromo-1,1-dichloro-3,7-dimethyl-2,7-octadiene (2.64), 4,8-dibromo-1,1,7-trichloro-3,7-dimethyl-2,5-octadiene (2.65) and 3,4 ,6,7-tetrachloro-3, 7-dimethyl-1-octene (2.63) as well as eight new compounds, including five halogenated monoterpene aldehydes. The new compounds were identified by 1D and 2D NMR spectroscopic techniques as: 8-Bromo-6,7-dichloro-3,7-dimethyl-octa-2,4-dienal (2.72), 8-Bromo-1,1,2,7-tetrachloro-3,7-dimethyl-octa-3,5-diene (2.70), 4,8-Dichloro-3,7-dimethyl-octa-2,4,6-trienal (2.74), 4-Bromo-8-chloro-3, 7-di methyl-octa-2, 6-dienal (2 76), 8-Bromo-4-chloro-3, 7-dimethyl-octa-2,4 ,6-trienaI (2.75), 4-Bromo-1,3,6,7-tetrachloro-3 ,7-dimethyl-octa-1,4-diene (2.71), 8-Bromo-1,3,4,7-tetrachloro-3,7-dimethyl-octa-1,5-diene (2.69), 4,6-Dibromo-3,7 -dimethyl-octa-2,7-dienal (2.73). All compounds were screened for antimicrobial activity, brine shrimp lethality and cytotoxicity towards oesophageal cancer cells. Compound 2.68 was toxic to brine shrimp larvae at a concentration of 50 μ/mL. It also showed promising activity towards oesophageal cancer cells with an IC₅₀, of 2 μg/mL.
- Full Text:
- Date Issued: 2005
A polarimetric method for collagenase activity measurement
- Brüning, Adrian Rudolf Nicolaus Ernst
- Authors: Brüning, Adrian Rudolf Nicolaus Ernst
- Date: 1992
- Subjects: Collagenases -- Research , Hides and skins -- Preservation -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4052 , http://hdl.handle.net/10962/d1004113 , Collagenases -- Research , Hides and skins -- Preservation -- Research
- Description: A polarimetric method for monitoring the rate of soluble collagen breakdown by collagenase enzyme action has been developed. The method represents an extension of previous physicochemical techniques based on viscometry, but is simpler and easier to carry out, particularly in the case of reaction rate studies. The method was developed arising from reports of collagenase activity measurement on inappropriate substrates such as gelatin, modified collagens and synthetic polypeptides. The optical method depends on measurement of the loss in optical rotation in solutions of soluble calfskin collagen resulting from initial enzymic cleavage of the collagen trip1e-helix, followed by spontaneous unwinding of the resultant unstable helical fragments. Specific assay conditions were chosen to ensure that the loss in optical rotation following enzymic cleavage was rapid and complete. The method is specific since in the absence of collagenase, non-specific proteinases produce only a limited decrease in solution optical activity. The method has also been compared with established physicochemical assay techniques and compares favourably with both viscometric and titrimetric collagenase assays. The availability of a rapid, sensitive and quantitative procedure for measurement of collagenase activity provides a convenient means for detecting the presence of collagenase in solution and examination of hide bacterial cultures for collagenase production. In addition, a study of biocidal compounds of potential interest in hide preservation for possible inhibitory effects on collagenase is conveniently carried out with the method. Fundamental research into synergistic action in enzymic hydrolysis of collagen is now possible, providing valuable insight into the mechanism of raw hide biodeterioration.
- Full Text:
- Date Issued: 1992
- Authors: Brüning, Adrian Rudolf Nicolaus Ernst
- Date: 1992
- Subjects: Collagenases -- Research , Hides and skins -- Preservation -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4052 , http://hdl.handle.net/10962/d1004113 , Collagenases -- Research , Hides and skins -- Preservation -- Research
- Description: A polarimetric method for monitoring the rate of soluble collagen breakdown by collagenase enzyme action has been developed. The method represents an extension of previous physicochemical techniques based on viscometry, but is simpler and easier to carry out, particularly in the case of reaction rate studies. The method was developed arising from reports of collagenase activity measurement on inappropriate substrates such as gelatin, modified collagens and synthetic polypeptides. The optical method depends on measurement of the loss in optical rotation in solutions of soluble calfskin collagen resulting from initial enzymic cleavage of the collagen trip1e-helix, followed by spontaneous unwinding of the resultant unstable helical fragments. Specific assay conditions were chosen to ensure that the loss in optical rotation following enzymic cleavage was rapid and complete. The method is specific since in the absence of collagenase, non-specific proteinases produce only a limited decrease in solution optical activity. The method has also been compared with established physicochemical assay techniques and compares favourably with both viscometric and titrimetric collagenase assays. The availability of a rapid, sensitive and quantitative procedure for measurement of collagenase activity provides a convenient means for detecting the presence of collagenase in solution and examination of hide bacterial cultures for collagenase production. In addition, a study of biocidal compounds of potential interest in hide preservation for possible inhibitory effects on collagenase is conveniently carried out with the method. Fundamental research into synergistic action in enzymic hydrolysis of collagen is now possible, providing valuable insight into the mechanism of raw hide biodeterioration.
- Full Text:
- Date Issued: 1992
An evaluation of Mimorista pulchellalis (Dyar) (Lepidoptera : Pyraustidae) as a biocontrol agent against jointed cactus in South Africa
- Authors: Nieman, Erik
- Date: 1984
- Subjects: Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5812 , http://hdl.handle.net/10962/d1007052 , Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Description: From the introduction: The work on Mimorista is divided into two sections: a laboratory orientated study which describes the biology and rearing techniques and a field orientated study where the establishment of the insect and its impact on jointed cactus populations are examined. In the final chapters the integration of this insect in the current control program are discussed and recommendations regarding its future in South Africa are given.
- Full Text:
- Date Issued: 1984
- Authors: Nieman, Erik
- Date: 1984
- Subjects: Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5812 , http://hdl.handle.net/10962/d1007052 , Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Description: From the introduction: The work on Mimorista is divided into two sections: a laboratory orientated study which describes the biology and rearing techniques and a field orientated study where the establishment of the insect and its impact on jointed cactus populations are examined. In the final chapters the integration of this insect in the current control program are discussed and recommendations regarding its future in South Africa are given.
- Full Text:
- Date Issued: 1984
Properties of traveling ionospheric disturbances (TIDs) over the Western Cape, South Africa
- Authors: Tyalimpi, Vumile Mike
- Date: 2015
- Subjects: Doppler radar , Geographic information systems , Traveling ionospheric disturbances -- south Africa , Ionospheric disturbances -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5557 , http://hdl.handle.net/10962/d1017901
- Description: Travelling Ionospheric Disturbances (TIDs) are said to be produced by atmospheric gravitational waves propagating through the neutral ionosphere. These are smaller in amplitude and period when compared to most ionospheric disturbances and hence more difficult to measure. Very little is known about the properties of the travelling ionospheric disturbances (TIDs) over the Southern Hemisphere regions since studies have been conducted mostly over the Northern Hemisphere regions. This study presents a framework, using a High Frequency (HF) Doppler radar to investigate the physical properties and the possible driving mechanisms of TIDs. This research focuses on studying the characteristics of the TIDs, such as period, velocity and temporal variations, using HF Doppler measurements taken in South Africa. By making use of a Wavelet Analysis technique, the TIDs’ characteristics were determined. A statistical summary on speed and direction of propagation of the observed TIDs was performed. The winter medium scale travelling ionospheric disturbances (MSTIDs) observed are generally faster than the summer MSTIDs. For all seasons, the MSTIDs had a preferred south-southwest direction of propagation. Most of the large scale travelling ionospheric disturbances (LSTIDs) were observed during the night and of these, the spring LSTIDs were fastest when compared to autumn and summer LSTIDs. The general direction of travel of the observed LSTIDs is south-southeast. Total Electron Content (TEC), derived from Global Positioning System (GPS) measurements, were used to validate some of the TID results obtained from the HF Doppler data. The Horizontal Wind Model (HWM07), magnetic K index, and solar terminators were used to determine the possible sources of the observed TIDs. Only 41% of the observed TIDs were successfully linked to their possible sources of excitation. The information gathered from this study will be valuable in future radio communications and will serve as means to improve the existing ionospheric models over the South African region.
- Full Text:
- Date Issued: 2015
- Authors: Tyalimpi, Vumile Mike
- Date: 2015
- Subjects: Doppler radar , Geographic information systems , Traveling ionospheric disturbances -- south Africa , Ionospheric disturbances -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5557 , http://hdl.handle.net/10962/d1017901
- Description: Travelling Ionospheric Disturbances (TIDs) are said to be produced by atmospheric gravitational waves propagating through the neutral ionosphere. These are smaller in amplitude and period when compared to most ionospheric disturbances and hence more difficult to measure. Very little is known about the properties of the travelling ionospheric disturbances (TIDs) over the Southern Hemisphere regions since studies have been conducted mostly over the Northern Hemisphere regions. This study presents a framework, using a High Frequency (HF) Doppler radar to investigate the physical properties and the possible driving mechanisms of TIDs. This research focuses on studying the characteristics of the TIDs, such as period, velocity and temporal variations, using HF Doppler measurements taken in South Africa. By making use of a Wavelet Analysis technique, the TIDs’ characteristics were determined. A statistical summary on speed and direction of propagation of the observed TIDs was performed. The winter medium scale travelling ionospheric disturbances (MSTIDs) observed are generally faster than the summer MSTIDs. For all seasons, the MSTIDs had a preferred south-southwest direction of propagation. Most of the large scale travelling ionospheric disturbances (LSTIDs) were observed during the night and of these, the spring LSTIDs were fastest when compared to autumn and summer LSTIDs. The general direction of travel of the observed LSTIDs is south-southeast. Total Electron Content (TEC), derived from Global Positioning System (GPS) measurements, were used to validate some of the TID results obtained from the HF Doppler data. The Horizontal Wind Model (HWM07), magnetic K index, and solar terminators were used to determine the possible sources of the observed TIDs. Only 41% of the observed TIDs were successfully linked to their possible sources of excitation. The information gathered from this study will be valuable in future radio communications and will serve as means to improve the existing ionospheric models over the South African region.
- Full Text:
- Date Issued: 2015
A case study exploring the level of awareness of NCP Chlorchem's staff of environmental costs associated with hazardous waste
- Tlhapane, Keatlaretse Kefilwe
- Authors: Tlhapane, Keatlaretse Kefilwe
- Date: 2014
- Subjects: Chlorchem (Firm) , Environmental auditing -- South Africa -- Ekurhuleni , Hazardous wastes -- South Africa -- Ekurhuleni , Hazardous wastes -- Environmental aspects , Hazardous wastes -- Economic aspects , Hazardous wastes -- Management , Hazardous wastes -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:841 , http://hdl.handle.net/10962/d1015639
- Description: [Integrative executive summary] NCP Chlorchem (Pty) Ltd manufactures and distributes Chlor alkali products such as chlorine, hydrochloric acid, caustic soda flakes, etc. and in the process generates both hazardous and general waste. Following changes in South African waste management legislation in 2011, the organisation’s waste service provider had to increase the costs associated with the handling of site’s hazardous waste. Top management of NCP Chlorchem (Pty) Ltd requested a meeting with the waste service provider in order to establish the reasons behind the price increase. In that meeting, which the researcher attended, the waste service provider explained the changes in waste legislation and how it was going to impact on their business. Top management understood the reasons behind the price increase; however, they requested the waste service provider to review the price increase. The waste service provider gave the top management of NCP Chlorchem (Pty) Ltd assurance that they were going to discuss the price reduction request with their own senior management and would provide feedback. The researcher did not participate in the feedback meetings; however, to this day, NCP Chlorchem (Pty) Ltd still uses the services of the same waste service provider. The effect the escalating annual waste handling costs has had on NCP Chlorchem (Pty) Ltd’s management team led to the study. Environmental impacts have costs that directly impact on company’s bottom line, such as the costs associated with the generation of waste. Although environmental costs are only one of the many costs incurred by businesses, they deserve management’s attention. According to Jasch (2003), there is an apparent lack of awareness and understanding of the magnitude of the environmental costs generated by organisations, and many opportunities for cost savings through good environmental management are lost. However, using a relatively new tool in environmental management, that is, environmental management accounting (EMA), management would ensure that relevant and significant environmental costs are considered when making business decisions (Jasch, 2003). The main purpose of the thesis is to explore the level of awareness of environmental costs associated with hazardous waste within NCP Chlorchem (Pty) Ltd. In order to carry out the study, literature about environmental and cost accounting as well as literature on waste management was reviewed. Questionnaires were distributed to staff members, and meetings were held with different senior personnel. This case study seeks to answer the following questions: What is NCP Chlorchem (Pty) Ltd’s staff members’ level of understanding of waste management? What is the level of awareness of NCP Chlorchem (Pty) Ltd’s staff of environmental costs with regard to the generation, handling, transportation and disposal of hazardous waste? How can the current traditional accounting within the organisation be integrated with environmental management accounting? The findings of the first research objective revealed that staff members knew the site’s waste streams as per the South African legal definition of waste and as identified in the site’s environmental management system documentation. The conceptual approach to waste management is underpinned by the waste hierarchy. The respondents support the waste hierarchy in its approach to waste management, which is prevention of waste, reduction, reuse, recycle and safe disposal of waste as the last resort. Lack of awareness of environmental management, among other things, was cited as the cause of waste. In addition to that, the respondents believe the waste hierarchy can be achieved by employing recycling facilities, following procedures and by carrying out environmental awareness campaigns. Improving process design and control and including changes in raw material was cited, among other things, as the respondents’ perception on how waste can be reduced. The findings of the respondents’ understanding of waste hierarchy revealed that staff members understood waste management. The respondents cited the impacts of waste on the business as financial impact on the business, impact on their bonuses, and possible loss of business. In relation to the second research objective, it was found that staff members knew the hazardous waste streams and identified amongst other waste, sludge and chlorine emissions as NCP Chlorchem (Pty) Ltd’s hazardous waste. However, with regard to environmental management accounting data, an average of 55.1% of respondents were not familiar with the physical and monetary components of EMA. An average of 19.6% of respondents who were aware of EMA might have been senior personnel. It could further be established that those who were familiar with EMA information were actually working with the data, either for reporting purposes, or for employing waste minimisation strategies, as well as awareness purposes, to their juniors. On average, 80% of the respondents perceived the production department as the area within site that has the EMA information.
- Full Text:
- Date Issued: 2014
- Authors: Tlhapane, Keatlaretse Kefilwe
- Date: 2014
- Subjects: Chlorchem (Firm) , Environmental auditing -- South Africa -- Ekurhuleni , Hazardous wastes -- South Africa -- Ekurhuleni , Hazardous wastes -- Environmental aspects , Hazardous wastes -- Economic aspects , Hazardous wastes -- Management , Hazardous wastes -- Law and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:841 , http://hdl.handle.net/10962/d1015639
- Description: [Integrative executive summary] NCP Chlorchem (Pty) Ltd manufactures and distributes Chlor alkali products such as chlorine, hydrochloric acid, caustic soda flakes, etc. and in the process generates both hazardous and general waste. Following changes in South African waste management legislation in 2011, the organisation’s waste service provider had to increase the costs associated with the handling of site’s hazardous waste. Top management of NCP Chlorchem (Pty) Ltd requested a meeting with the waste service provider in order to establish the reasons behind the price increase. In that meeting, which the researcher attended, the waste service provider explained the changes in waste legislation and how it was going to impact on their business. Top management understood the reasons behind the price increase; however, they requested the waste service provider to review the price increase. The waste service provider gave the top management of NCP Chlorchem (Pty) Ltd assurance that they were going to discuss the price reduction request with their own senior management and would provide feedback. The researcher did not participate in the feedback meetings; however, to this day, NCP Chlorchem (Pty) Ltd still uses the services of the same waste service provider. The effect the escalating annual waste handling costs has had on NCP Chlorchem (Pty) Ltd’s management team led to the study. Environmental impacts have costs that directly impact on company’s bottom line, such as the costs associated with the generation of waste. Although environmental costs are only one of the many costs incurred by businesses, they deserve management’s attention. According to Jasch (2003), there is an apparent lack of awareness and understanding of the magnitude of the environmental costs generated by organisations, and many opportunities for cost savings through good environmental management are lost. However, using a relatively new tool in environmental management, that is, environmental management accounting (EMA), management would ensure that relevant and significant environmental costs are considered when making business decisions (Jasch, 2003). The main purpose of the thesis is to explore the level of awareness of environmental costs associated with hazardous waste within NCP Chlorchem (Pty) Ltd. In order to carry out the study, literature about environmental and cost accounting as well as literature on waste management was reviewed. Questionnaires were distributed to staff members, and meetings were held with different senior personnel. This case study seeks to answer the following questions: What is NCP Chlorchem (Pty) Ltd’s staff members’ level of understanding of waste management? What is the level of awareness of NCP Chlorchem (Pty) Ltd’s staff of environmental costs with regard to the generation, handling, transportation and disposal of hazardous waste? How can the current traditional accounting within the organisation be integrated with environmental management accounting? The findings of the first research objective revealed that staff members knew the site’s waste streams as per the South African legal definition of waste and as identified in the site’s environmental management system documentation. The conceptual approach to waste management is underpinned by the waste hierarchy. The respondents support the waste hierarchy in its approach to waste management, which is prevention of waste, reduction, reuse, recycle and safe disposal of waste as the last resort. Lack of awareness of environmental management, among other things, was cited as the cause of waste. In addition to that, the respondents believe the waste hierarchy can be achieved by employing recycling facilities, following procedures and by carrying out environmental awareness campaigns. Improving process design and control and including changes in raw material was cited, among other things, as the respondents’ perception on how waste can be reduced. The findings of the respondents’ understanding of waste hierarchy revealed that staff members understood waste management. The respondents cited the impacts of waste on the business as financial impact on the business, impact on their bonuses, and possible loss of business. In relation to the second research objective, it was found that staff members knew the hazardous waste streams and identified amongst other waste, sludge and chlorine emissions as NCP Chlorchem (Pty) Ltd’s hazardous waste. However, with regard to environmental management accounting data, an average of 55.1% of respondents were not familiar with the physical and monetary components of EMA. An average of 19.6% of respondents who were aware of EMA might have been senior personnel. It could further be established that those who were familiar with EMA information were actually working with the data, either for reporting purposes, or for employing waste minimisation strategies, as well as awareness purposes, to their juniors. On average, 80% of the respondents perceived the production department as the area within site that has the EMA information.
- Full Text:
- Date Issued: 2014
Variation in breeding systems, floral morphology and nectar properties in three co-occurring Erica species with contrasting pollination syndromes
- Authors: Lombardi, Giorgio Colombo
- Date: 2015
- Subjects: Ericas -- South Africa -- Western Cape , Ericas -- Morphology , Ericas -- Reproduction , Ericas -- Pollination , Pollination by animals , Pollination by insects , Nectar
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4273 , http://hdl.handle.net/10962/d1018567
- Description: The genus Erica is the most species rich in the Cape Floristic Kingdom, yet there are limited data on the various flower-pollinator interactions and breeding systems for the majority of these species. Until recently research has focussed on predictive floral traits, including flower shape, length of corolla and corolla opening to identify likely pollinators in this genus. Field observations provide an empirical test of such predictions. This study investigated three species of Erica and compared their pollination and breeding systems and floral biology. Research, including field experiments and pollinator observations was undertaken in the Vogelgat Private Nature Reserve, Maanschynkop Nature Reserve and Boskloof farm in the vicinity of Hermanus in the Western Cape Province of South Africa. Field observations were conducted to determine what flower- visitor interactions occurred, while nectar volumes and sugar concentrations were measured to determine the value of the reward to the different visitors. Selective exclusion and breeding system experiments were carried out to determine whether these Erica species were capable of autonomous self-fertilization or whether they are pollinator dependent for breeding success. The unusual morphology of Erica lanuginosa suggested rodent-pollination. Field observations, including photographs of visits to plants in the field, the presence of pollen in scat sample and selective exclusion and breeding system experiments identified rodents, primarily Acomys subspinosus to be the primary pollinator. Long-proboscid flies of the family Nemestrinidae were found, on the basis of field observations to be responsible for pollination of the endemic Erica aristata. This was supported by with nectar volume and sugar concentration samples which are consistent with other long-proboscid fly-pollinated plant species. Selective exclusion and breeding system experiments undertaken confirmed that Erica aristata required a pollinator to set seed. Observations and breeding trials revealed bird-pollination in Erica sessiliflora. Nectar volume and sugar concentrations in Erica sessiliflora were in line with other sunbird-pollinated plant species, providing the necessary rewards for sunbirds visiting this species. Specialised pollination by single pollinators was found in all three species and results from breeding system experiments show that out-crossing is important. Further research into pollinator-flower interactions in the genus Erica is necessary, not least to understand more fully the conservation importance of specific pollinators.
- Full Text:
- Date Issued: 2015
- Authors: Lombardi, Giorgio Colombo
- Date: 2015
- Subjects: Ericas -- South Africa -- Western Cape , Ericas -- Morphology , Ericas -- Reproduction , Ericas -- Pollination , Pollination by animals , Pollination by insects , Nectar
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4273 , http://hdl.handle.net/10962/d1018567
- Description: The genus Erica is the most species rich in the Cape Floristic Kingdom, yet there are limited data on the various flower-pollinator interactions and breeding systems for the majority of these species. Until recently research has focussed on predictive floral traits, including flower shape, length of corolla and corolla opening to identify likely pollinators in this genus. Field observations provide an empirical test of such predictions. This study investigated three species of Erica and compared their pollination and breeding systems and floral biology. Research, including field experiments and pollinator observations was undertaken in the Vogelgat Private Nature Reserve, Maanschynkop Nature Reserve and Boskloof farm in the vicinity of Hermanus in the Western Cape Province of South Africa. Field observations were conducted to determine what flower- visitor interactions occurred, while nectar volumes and sugar concentrations were measured to determine the value of the reward to the different visitors. Selective exclusion and breeding system experiments were carried out to determine whether these Erica species were capable of autonomous self-fertilization or whether they are pollinator dependent for breeding success. The unusual morphology of Erica lanuginosa suggested rodent-pollination. Field observations, including photographs of visits to plants in the field, the presence of pollen in scat sample and selective exclusion and breeding system experiments identified rodents, primarily Acomys subspinosus to be the primary pollinator. Long-proboscid flies of the family Nemestrinidae were found, on the basis of field observations to be responsible for pollination of the endemic Erica aristata. This was supported by with nectar volume and sugar concentration samples which are consistent with other long-proboscid fly-pollinated plant species. Selective exclusion and breeding system experiments undertaken confirmed that Erica aristata required a pollinator to set seed. Observations and breeding trials revealed bird-pollination in Erica sessiliflora. Nectar volume and sugar concentrations in Erica sessiliflora were in line with other sunbird-pollinated plant species, providing the necessary rewards for sunbirds visiting this species. Specialised pollination by single pollinators was found in all three species and results from breeding system experiments show that out-crossing is important. Further research into pollinator-flower interactions in the genus Erica is necessary, not least to understand more fully the conservation importance of specific pollinators.
- Full Text:
- Date Issued: 2015
The effect of temperature and photoperiod on the digestive physiology of the South African abalone Haliotis midae
- Authors: Dixon, Mark Geoffrey
- Date: 1992
- Subjects: Abalone culture , Gastropoda -- Physiology , Gastropoda -- Food , Abalones -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5276 , http://hdl.handle.net/10962/d1005120 , Abalone culture , Gastropoda -- Physiology , Gastropoda -- Food , Abalones -- South Africa
- Description: Inadequate information of the nutritive physiology and the dietary requirements of abalone are the principle factors that currently limit the development of a formulated feed for the commercial culture of Haliotis midae. The need to develop a method to determine apparent digestibility co-efficient's for abalone in order to facilitate further applied nutritional research was identified. Animals between 50 and 80 mm were collected from natural stocks along the east Cape coast of South Africa at Port Alfred and Great Fish point, and acclimated to laboratory conditions. Initial trials demonstrated that H. midae accepted and preferred a semi-purified diet to the seaweed Plocamium corallorhiza, one of the main components of it's natural diet. A technique of determining apparent digestibility co-efficient's (ADC) using the indirect method with chromic oxide as an inert marker was developed. Digestibility trials yielded higher dry matter (DMADC) and crude protein apparent digestibility co-efficient's (CPADC) for the semi-purified diet than for two species of algae, Gelidium amanzii and P. corallorhiza (83.7% and 95.6%, 70.7% and 80.0%, and 29.9% and 57.3% respectively). The ability of the animals to utilize terrestrial animal and plant ingredients efficiently makes it feasible to use conventional feed ingredients in formulated feeds for H. midae. Trials to determine the effect of different temperatures (15°C, 18°C and 22°C) on DMADC and CPADC of the semipurified diet showed that peak digestibility occurred at 18°C. There was also a positive relationship between temperature and consumption rate. Although no enzyme studies with H. midae have been conducted, the peak ADC's at 18°C is attributed to an increase in enzyme activity at this temperature. Transit time, an inverse function of temperature and consumption, is considered to be responsible for the decrease in the ADC' s at 22°C in conjunction with a possible decrease in enzyme activity at this temperature. A photoperiod trial to investigate the effect of darkness on DMADC and CPADC of the semi-purified diet revealed that digestive efficiency decreased with increasing hours of darkness. There was also a positive relationship between duration of darkness and the rate of consumption. The decrease in ADC's is attributed to decreased transit times as the duration of darkness increased . The contribution of this project to the understanding of abalone nutrition, the development of a formulated abalone feed and systems design for abalone farms is discussed.
- Full Text:
- Date Issued: 1992
- Authors: Dixon, Mark Geoffrey
- Date: 1992
- Subjects: Abalone culture , Gastropoda -- Physiology , Gastropoda -- Food , Abalones -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5276 , http://hdl.handle.net/10962/d1005120 , Abalone culture , Gastropoda -- Physiology , Gastropoda -- Food , Abalones -- South Africa
- Description: Inadequate information of the nutritive physiology and the dietary requirements of abalone are the principle factors that currently limit the development of a formulated feed for the commercial culture of Haliotis midae. The need to develop a method to determine apparent digestibility co-efficient's for abalone in order to facilitate further applied nutritional research was identified. Animals between 50 and 80 mm were collected from natural stocks along the east Cape coast of South Africa at Port Alfred and Great Fish point, and acclimated to laboratory conditions. Initial trials demonstrated that H. midae accepted and preferred a semi-purified diet to the seaweed Plocamium corallorhiza, one of the main components of it's natural diet. A technique of determining apparent digestibility co-efficient's (ADC) using the indirect method with chromic oxide as an inert marker was developed. Digestibility trials yielded higher dry matter (DMADC) and crude protein apparent digestibility co-efficient's (CPADC) for the semi-purified diet than for two species of algae, Gelidium amanzii and P. corallorhiza (83.7% and 95.6%, 70.7% and 80.0%, and 29.9% and 57.3% respectively). The ability of the animals to utilize terrestrial animal and plant ingredients efficiently makes it feasible to use conventional feed ingredients in formulated feeds for H. midae. Trials to determine the effect of different temperatures (15°C, 18°C and 22°C) on DMADC and CPADC of the semipurified diet showed that peak digestibility occurred at 18°C. There was also a positive relationship between temperature and consumption rate. Although no enzyme studies with H. midae have been conducted, the peak ADC's at 18°C is attributed to an increase in enzyme activity at this temperature. Transit time, an inverse function of temperature and consumption, is considered to be responsible for the decrease in the ADC' s at 22°C in conjunction with a possible decrease in enzyme activity at this temperature. A photoperiod trial to investigate the effect of darkness on DMADC and CPADC of the semi-purified diet revealed that digestive efficiency decreased with increasing hours of darkness. There was also a positive relationship between duration of darkness and the rate of consumption. The decrease in ADC's is attributed to decreased transit times as the duration of darkness increased . The contribution of this project to the understanding of abalone nutrition, the development of a formulated abalone feed and systems design for abalone farms is discussed.
- Full Text:
- Date Issued: 1992
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