A basic model to predict water quality changes in the Vaal Dam
- Authors: Kneidinger, Tanya Michaela
- Date: 2012-02-06
- Subjects: Water quality , Water quality management
- Type: Thesis
- Identifier: uj:2011 , http://hdl.handle.net/10210/4364
- Description: M.Sc. , The Vaal Dam (South Africa) and its tributaries have been extensively affected by domestic, mining, agricultural and industrial activities, as well as the release of effluents. These practices have contributed to large-scale algal blooms that have caused serious ecological, aesthetic, water purification and water distribution problems. This study addresses the need to develop a system that enables forecasts to be made regarding potential changes in the water quality ofthe Vaal Dam, especially with regards to predicting algal blooms. The primary aim was to develop a simple spreadsheet based model to predict the occurrence of algal blooms and other water quality changes in the Vaal Dam, making use of environmental parameters recorded at several sites located upstream of the Rand Water intake point at the Vaal Dam wall. Accurately forecasting sudden changes in water quality would enable proactive resource management, ensuring that Rand Water maintains a high standard of potable water delivered to its customers. Statistical model equations, to predict the concentrations of various water quality constituents, were obtained by step-wise regression analysis. These equations were then entered into MS-Excel spreadsheets. This allowed the input of environmental data and the subsequent calculation of the predicted value. This also allowed for the manipulation of various parameters to forecast the effects any changing values will have on the water quality. These "if-then'' scenarios would be of considerable use in implementing management measures to achieve the desired water quality. The performance of the model was statistically tested to determine if it adequately represents the study system. The models to determine chlorophyll-a concentration and several other water quality constituents proved to be fairly accurate in representing the study system. However, the model to predict nitrate concentrations did not perform satisfactorily. The limitations in model performance were attributed to the low frequency of water quality sampling and the effects of undetermined variables not represented by the water quality parameters selected for model development. The model is compact, does not require specialised software, and is applicable in practice. The predictive and scenario forecasting abilities make this model useful for the identification, monitoring and prediction of changes or trends in water quality over time. The benefits arising from this model will thus contribute to more cost efficient water treatment, improved response times to algal blooms, improved decision-making and proactive water resource management.
- Full Text:
- Authors: Kneidinger, Tanya Michaela
- Date: 2012-02-06
- Subjects: Water quality , Water quality management
- Type: Thesis
- Identifier: uj:2011 , http://hdl.handle.net/10210/4364
- Description: M.Sc. , The Vaal Dam (South Africa) and its tributaries have been extensively affected by domestic, mining, agricultural and industrial activities, as well as the release of effluents. These practices have contributed to large-scale algal blooms that have caused serious ecological, aesthetic, water purification and water distribution problems. This study addresses the need to develop a system that enables forecasts to be made regarding potential changes in the water quality ofthe Vaal Dam, especially with regards to predicting algal blooms. The primary aim was to develop a simple spreadsheet based model to predict the occurrence of algal blooms and other water quality changes in the Vaal Dam, making use of environmental parameters recorded at several sites located upstream of the Rand Water intake point at the Vaal Dam wall. Accurately forecasting sudden changes in water quality would enable proactive resource management, ensuring that Rand Water maintains a high standard of potable water delivered to its customers. Statistical model equations, to predict the concentrations of various water quality constituents, were obtained by step-wise regression analysis. These equations were then entered into MS-Excel spreadsheets. This allowed the input of environmental data and the subsequent calculation of the predicted value. This also allowed for the manipulation of various parameters to forecast the effects any changing values will have on the water quality. These "if-then'' scenarios would be of considerable use in implementing management measures to achieve the desired water quality. The performance of the model was statistically tested to determine if it adequately represents the study system. The models to determine chlorophyll-a concentration and several other water quality constituents proved to be fairly accurate in representing the study system. However, the model to predict nitrate concentrations did not perform satisfactorily. The limitations in model performance were attributed to the low frequency of water quality sampling and the effects of undetermined variables not represented by the water quality parameters selected for model development. The model is compact, does not require specialised software, and is applicable in practice. The predictive and scenario forecasting abilities make this model useful for the identification, monitoring and prediction of changes or trends in water quality over time. The benefits arising from this model will thus contribute to more cost efficient water treatment, improved response times to algal blooms, improved decision-making and proactive water resource management.
- Full Text:
An evaluation of invertebrate dynamics in a drinking water distribution system: a South African perspective
- Authors: Shaddock, Bridget
- Date: 2008-10-16T05:48:04Z
- Subjects: Water quality management , Effect of water quality on aquatic invertebrates , Drinking water purification
- Type: Thesis
- Identifier: uj:12354 , http://hdl.handle.net/10210/1213
- Description: M.Sc. , The occurrence of invertebrates in drinking water supplies is a common consumer complaint with studies showing that very few drinking water distribution networks are totally free of organisms. A detailed investigation of different types of metazoan animals in the drinking water supply networks of South Africa has not been undertaken. In limited worldwide studies, invertebrates (mainly Amphipoda, Chironomidae, Cladocera, Copepoda and Ostracoda) have been detected in produced drinking water. In countries that have started monitoring these organisms, the quality of the produced water has improved due to the improved methods of filtering. The occurrence of “worms” (Nematodes and Diptera) and Crustaceans decreases the aesthetic value of the drinking water, and pathogenic organisms, which may also be associated with them, can affect human health. Limited reference works have been compiled during the conducted studies on drinking water distribution networks throughout the world. All fresh water invertebrates have the potential to be passed into the drinking water supply network (Rising mains, pipelines, reservoirs, and consumer taps). There are few complete reference works available for fresh water invertebrates occurring in the fresh water sources and those of Southern Africa. Therefore, there are no reference works regarding fresh water invertebrates that can be used to monitor drinking water supply networks in South Africa. , Prof. J.H.J. van Vuren
- Full Text:
- Authors: Shaddock, Bridget
- Date: 2008-10-16T05:48:04Z
- Subjects: Water quality management , Effect of water quality on aquatic invertebrates , Drinking water purification
- Type: Thesis
- Identifier: uj:12354 , http://hdl.handle.net/10210/1213
- Description: M.Sc. , The occurrence of invertebrates in drinking water supplies is a common consumer complaint with studies showing that very few drinking water distribution networks are totally free of organisms. A detailed investigation of different types of metazoan animals in the drinking water supply networks of South Africa has not been undertaken. In limited worldwide studies, invertebrates (mainly Amphipoda, Chironomidae, Cladocera, Copepoda and Ostracoda) have been detected in produced drinking water. In countries that have started monitoring these organisms, the quality of the produced water has improved due to the improved methods of filtering. The occurrence of “worms” (Nematodes and Diptera) and Crustaceans decreases the aesthetic value of the drinking water, and pathogenic organisms, which may also be associated with them, can affect human health. Limited reference works have been compiled during the conducted studies on drinking water distribution networks throughout the world. All fresh water invertebrates have the potential to be passed into the drinking water supply network (Rising mains, pipelines, reservoirs, and consumer taps). There are few complete reference works available for fresh water invertebrates occurring in the fresh water sources and those of Southern Africa. Therefore, there are no reference works regarding fresh water invertebrates that can be used to monitor drinking water supply networks in South Africa. , Prof. J.H.J. van Vuren
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An integrated manual for the management, control and protection of the Vaal River Barrage reservoir
- Authors: Van Wyk, Francois
- Date: 2009-01-29T12:10:25Z
- Subjects: Reservoirs , Water-supply , Water quality management , Vaal River (South Africa)
- Type: Thesis
- Identifier: uj:14860 , http://hdl.handle.net/10210/1981
- Description: M.Sc. , The Vaal River Barrage reservoir (VRBR) was constructed by Rand Water in 1923 for the purpose of ensuring an adequate raw water supply to meet the potable water requirements of the Pretoria, Witwatersrand and Vaal Triangle regions, and today this is still the main purpose of this body of water. Due to the strategic importance of the Vaal River Barrage catchment and the impact of activities in the catchment on water resources, it is seen as of the utmost importance for the authorities to make a joint effort and co-ordinate action to solve problems in the catchment. A number of different acts have reference to the management of the Barrage reservoir. These, together with Rand Water’s internal policies, are collated and described to provide a reference manual for the integrated management of the Vaal River Barrage reservoir. For completeness, all relevant policies are attached as appendices to the document.
- Full Text:
- Authors: Van Wyk, Francois
- Date: 2009-01-29T12:10:25Z
- Subjects: Reservoirs , Water-supply , Water quality management , Vaal River (South Africa)
- Type: Thesis
- Identifier: uj:14860 , http://hdl.handle.net/10210/1981
- Description: M.Sc. , The Vaal River Barrage reservoir (VRBR) was constructed by Rand Water in 1923 for the purpose of ensuring an adequate raw water supply to meet the potable water requirements of the Pretoria, Witwatersrand and Vaal Triangle regions, and today this is still the main purpose of this body of water. Due to the strategic importance of the Vaal River Barrage catchment and the impact of activities in the catchment on water resources, it is seen as of the utmost importance for the authorities to make a joint effort and co-ordinate action to solve problems in the catchment. A number of different acts have reference to the management of the Barrage reservoir. These, together with Rand Water’s internal policies, are collated and described to provide a reference manual for the integrated management of the Vaal River Barrage reservoir. For completeness, all relevant policies are attached as appendices to the document.
- Full Text:
Creating management thresholds for fish communities exposed to coal mining
- Authors: Jonker, Michiel-Nell
- Date: 2012-05-02
- Subjects: Fish communities - Effect of water pollution on , Coal mining - Environmental aspects , Environmental management , Environmental protection , Water quality management
- Type: Thesis
- Identifier: uj:2241 , http://hdl.handle.net/10210/4680
- Description: M.Sc. , This study aims to assess the potential impacts of coal mine activity on exposed fish assemblages in the Mpumalanga Highveld area. A control-impact-assessment method was applied, with sites located upstream and downstream from mining activity. All sites were located in the upper Olifants catchment. Field assessments were done over a high flow and low flow period. It was ascertained that water quality variables contributing towards differences between upstream and downstream environmental conditions are salt concentrations, pH and oxygen saturation. Alterations on fish community structures indicated a categorical decline in abundances and species richness at sites situated downstream from mining activity, while Fish Response Assessment Index (FRAI) scores similarly reflected more impaired fish assemblages at downstream sites. Redundancy analysis (RDA), using fish assemblages and FRAI driver metrics explained 36.5 % of variance obtained and reflected particular alteration in Barbus neefi, B. paludinosus, Tilapia sparrmanii and Pseudocrenilabrus philander populations. Sites most severely impacted were identified, as well as the main drivers responsible for changes in fish assemblages. The Cover metric contributed significantly (p<0.05 to variance measured. Subsequent community threshold management targets are presented for problem sites, which aim to manage each site at an ecological category one class higher than the Present Ecological State (PES).
- Full Text:
- Authors: Jonker, Michiel-Nell
- Date: 2012-05-02
- Subjects: Fish communities - Effect of water pollution on , Coal mining - Environmental aspects , Environmental management , Environmental protection , Water quality management
- Type: Thesis
- Identifier: uj:2241 , http://hdl.handle.net/10210/4680
- Description: M.Sc. , This study aims to assess the potential impacts of coal mine activity on exposed fish assemblages in the Mpumalanga Highveld area. A control-impact-assessment method was applied, with sites located upstream and downstream from mining activity. All sites were located in the upper Olifants catchment. Field assessments were done over a high flow and low flow period. It was ascertained that water quality variables contributing towards differences between upstream and downstream environmental conditions are salt concentrations, pH and oxygen saturation. Alterations on fish community structures indicated a categorical decline in abundances and species richness at sites situated downstream from mining activity, while Fish Response Assessment Index (FRAI) scores similarly reflected more impaired fish assemblages at downstream sites. Redundancy analysis (RDA), using fish assemblages and FRAI driver metrics explained 36.5 % of variance obtained and reflected particular alteration in Barbus neefi, B. paludinosus, Tilapia sparrmanii and Pseudocrenilabrus philander populations. Sites most severely impacted were identified, as well as the main drivers responsible for changes in fish assemblages. The Cover metric contributed significantly (p<0.05 to variance measured. Subsequent community threshold management targets are presented for problem sites, which aim to manage each site at an ecological category one class higher than the Present Ecological State (PES).
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Design and evaluation of a cost effective household drinking water treatment system
- Authors: Mahlangu, Themba Oranso
- Date: 2012-08-20
- Subjects: Drinking water treatment units , Water supply, Rural , Drinking water - Health aspects , Drinking water purification , Water treatment plants - Design and construction , Water quality management
- Type: Thesis
- Identifier: uj:2859 , http://hdl.handle.net/10210/6293
- Description: M.Sc. , The world is focusing on increasing the number of people who have access to safe drinking water due to the ascending numbers of drinking water related illnesses reported annually in rural areas where water is not treated before consumption. To meet this goal, household water treatment has to be introduced especially in places where homes are wide apart making centralised water treatment improbable. Most readily available household water treatment systems (HWTS) such as membrane filters may not be affordable in rural areas due to power requirements and degree of ability to use and maintain them. This study was therefore aimed at designing and constructing HWTS using readily available material such as sand, gravel, zeolites and clays. Five HWTS were designed, built, evaluated and compared based on their ability to remove chemical contaminants such as iron, arsenic and fluorides from drinking water. The types of filters that were used during this study are the biosand filter (BSF), a modified biosand filter with zeolites (BSFZ), a silver impregnated porous pot (SIPP) filter, a ceramic candle filter (CCF) and a bucket filter (BF). Effectiveness of the filters in reducing physical parameters such as turbidity and visual colour was also assessed. The water treatment devices had the following flow rates; 1.74 L/h – 19.20 L/h (BSFZ), 0.81 L/h – 6.84 L/h (BSF), 0.05 L/h – 2.49 L/h (SIPP) and 1.00 L/h – 4.00 L/h (CCF). The flow rates were high at the early stages of filter use and decreased with increase in the volume of water filtered through. The flow rates of the filters were affected by the turbidity of intake water which was between 1.74 NTU – 42.93 NTU and correlated to chlorophyll a concentrations. The household water treatment technologies reduced turbidity to levels less than 1 NTU (> 90% reduction) in the following order SIPP > BSFZ > BSF > CCF > BF. The filters achieved greater than 60% retention of calcium, magnesium, iron and arsenic. These contaminants with the exception of arsenic were reduced to acceptable levels of the South African National Standard of drinking water (SANS 241, 2004). Compared to the other filters, the BSFZ performed better in removing nitrates, phosphates and fluorides although the overall retention efficiency was low. Total organic carbon was removed greatly by the CCF (39%) and the least removal was by the BF. The overall performance of the filters in reducing contaminants from drinking water was in the order BSFZ > BSF > SIPP > CCF > BF. Filter washing vi resulted in an overall increase in the flow rates of the filters but negatively affected turbidity reduction. The filters still removed contaminants after total cumulative volumes of 1200 L (BSFZ, BSF, CCF and BF) and 300 L (SIPP) were filtered through the devices. The five evaluated filters have several advantages to the readily available technologies and the advantages include ease of construction, operation and maintenance. The filters are gravity driven and work independent of temperature. These HWTS incorporate safe storages fitted with spigots to eliminate recontamination of water when it is drawn for use. The filters can produce enough drinking and cooking water for a family of six members due to their high flow rates. The BSFZ, BSF, SIPP, CCF and BF may therefore be considered for treating contaminated water at household scale in places where water is taken directly from the source without treatment.
- Full Text:
- Authors: Mahlangu, Themba Oranso
- Date: 2012-08-20
- Subjects: Drinking water treatment units , Water supply, Rural , Drinking water - Health aspects , Drinking water purification , Water treatment plants - Design and construction , Water quality management
- Type: Thesis
- Identifier: uj:2859 , http://hdl.handle.net/10210/6293
- Description: M.Sc. , The world is focusing on increasing the number of people who have access to safe drinking water due to the ascending numbers of drinking water related illnesses reported annually in rural areas where water is not treated before consumption. To meet this goal, household water treatment has to be introduced especially in places where homes are wide apart making centralised water treatment improbable. Most readily available household water treatment systems (HWTS) such as membrane filters may not be affordable in rural areas due to power requirements and degree of ability to use and maintain them. This study was therefore aimed at designing and constructing HWTS using readily available material such as sand, gravel, zeolites and clays. Five HWTS were designed, built, evaluated and compared based on their ability to remove chemical contaminants such as iron, arsenic and fluorides from drinking water. The types of filters that were used during this study are the biosand filter (BSF), a modified biosand filter with zeolites (BSFZ), a silver impregnated porous pot (SIPP) filter, a ceramic candle filter (CCF) and a bucket filter (BF). Effectiveness of the filters in reducing physical parameters such as turbidity and visual colour was also assessed. The water treatment devices had the following flow rates; 1.74 L/h – 19.20 L/h (BSFZ), 0.81 L/h – 6.84 L/h (BSF), 0.05 L/h – 2.49 L/h (SIPP) and 1.00 L/h – 4.00 L/h (CCF). The flow rates were high at the early stages of filter use and decreased with increase in the volume of water filtered through. The flow rates of the filters were affected by the turbidity of intake water which was between 1.74 NTU – 42.93 NTU and correlated to chlorophyll a concentrations. The household water treatment technologies reduced turbidity to levels less than 1 NTU (> 90% reduction) in the following order SIPP > BSFZ > BSF > CCF > BF. The filters achieved greater than 60% retention of calcium, magnesium, iron and arsenic. These contaminants with the exception of arsenic were reduced to acceptable levels of the South African National Standard of drinking water (SANS 241, 2004). Compared to the other filters, the BSFZ performed better in removing nitrates, phosphates and fluorides although the overall retention efficiency was low. Total organic carbon was removed greatly by the CCF (39%) and the least removal was by the BF. The overall performance of the filters in reducing contaminants from drinking water was in the order BSFZ > BSF > SIPP > CCF > BF. Filter washing vi resulted in an overall increase in the flow rates of the filters but negatively affected turbidity reduction. The filters still removed contaminants after total cumulative volumes of 1200 L (BSFZ, BSF, CCF and BF) and 300 L (SIPP) were filtered through the devices. The five evaluated filters have several advantages to the readily available technologies and the advantages include ease of construction, operation and maintenance. The filters are gravity driven and work independent of temperature. These HWTS incorporate safe storages fitted with spigots to eliminate recontamination of water when it is drawn for use. The filters can produce enough drinking and cooking water for a family of six members due to their high flow rates. The BSFZ, BSF, SIPP, CCF and BF may therefore be considered for treating contaminated water at household scale in places where water is taken directly from the source without treatment.
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Determining the influences of land use patterns on the diatom, macroinvertebrate and riparian vegetation integrity of the Lower Harts/Vaal River systems
- Authors: Ferreira, Linette
- Date: 2010-05-26T06:13:04Z
- Subjects: Vaalharts Irrigation Scheme , Water quality management , Water quality biological assessment , Effect of water pollution on diatoms
- Type: Thesis
- Identifier: uj:6835 , http://hdl.handle.net/10210/3268
- Description: M.Sc. , Water resources in South Africa are scarce and need to be protected and managed in a sustainable way for future generations. Food supply is a great priority worldwide and the pressure to produce enough food has resulted in the expansion of irrigation and the steadily increasing use of fertilizers and pesticides to achieve higher yields. Rivers are impacted by agriculture through increased suspended sediment loads (which affects primary production, habitat reduction and introduction of absorbed pollutants), elevated nutrient inputs (which may increase the abundances of algae and aquatic plants), salinization and pesticide runoff (which eliminates species intolerant to these conditions and therefore impacts on the normal production of the river system). Aquatic biota plays an integral part in the functioning of aquatic ecosystems. Biological monitoring is used to assess ecosystem health and integrity. Biological communities reflect the overall integrity of the river ecosystem by integrating various stressors and therefore provide a broad measure of their synergistic effects. The research area falls within the Lower Vaal Water Management Area (WMA), which lies in the North-West and Northern Cape Provinces. The lower Vaal River and the Harts River (one of the tributaries of the Vaal) are the river systems under investigation in this study. Farming activities ranges from extensive livestock production and rain fed cultivation to intensive irrigation enterprises at Vaalharts (such as maize, cotton and groundnuts). The Vaalharts is the largest irrigation scheme in South Africa. Salinity is of concern in the lower reaches of the Harts- and Vaal Rivers, due to saline leachate from the Vaalharts irrigation scheme. Agricultural inputs are known to affect aquatic communities and chemicals (e.g. pesticides, herbicides, fertilizers) are extensively used in the Vaalharts irrigation scheme. At present there are no data on the effect of these chemicals on the aquatic biota of the lower Harts- and Vaal Rivers. The aims of this study were to assess the diatom- and macroinvertebrate community structures, ecosystem integrity and macroinvertebrate feeding traits (functional feeding groups – FFGs) in relation to land use.
- Full Text:
- Authors: Ferreira, Linette
- Date: 2010-05-26T06:13:04Z
- Subjects: Vaalharts Irrigation Scheme , Water quality management , Water quality biological assessment , Effect of water pollution on diatoms
- Type: Thesis
- Identifier: uj:6835 , http://hdl.handle.net/10210/3268
- Description: M.Sc. , Water resources in South Africa are scarce and need to be protected and managed in a sustainable way for future generations. Food supply is a great priority worldwide and the pressure to produce enough food has resulted in the expansion of irrigation and the steadily increasing use of fertilizers and pesticides to achieve higher yields. Rivers are impacted by agriculture through increased suspended sediment loads (which affects primary production, habitat reduction and introduction of absorbed pollutants), elevated nutrient inputs (which may increase the abundances of algae and aquatic plants), salinization and pesticide runoff (which eliminates species intolerant to these conditions and therefore impacts on the normal production of the river system). Aquatic biota plays an integral part in the functioning of aquatic ecosystems. Biological monitoring is used to assess ecosystem health and integrity. Biological communities reflect the overall integrity of the river ecosystem by integrating various stressors and therefore provide a broad measure of their synergistic effects. The research area falls within the Lower Vaal Water Management Area (WMA), which lies in the North-West and Northern Cape Provinces. The lower Vaal River and the Harts River (one of the tributaries of the Vaal) are the river systems under investigation in this study. Farming activities ranges from extensive livestock production and rain fed cultivation to intensive irrigation enterprises at Vaalharts (such as maize, cotton and groundnuts). The Vaalharts is the largest irrigation scheme in South Africa. Salinity is of concern in the lower reaches of the Harts- and Vaal Rivers, due to saline leachate from the Vaalharts irrigation scheme. Agricultural inputs are known to affect aquatic communities and chemicals (e.g. pesticides, herbicides, fertilizers) are extensively used in the Vaalharts irrigation scheme. At present there are no data on the effect of these chemicals on the aquatic biota of the lower Harts- and Vaal Rivers. The aims of this study were to assess the diatom- and macroinvertebrate community structures, ecosystem integrity and macroinvertebrate feeding traits (functional feeding groups – FFGs) in relation to land use.
- Full Text:
Development of sample preparation and chromatographic mass spectrometric techniques for determination of selected organic pollutants in wastewater
- Authors: Muckoya, Vallerie Akinyi
- Date: 2019
- Subjects: Organic water pollutants , Water quality management , Mass spectrometry , Sample preparation (Chemistry)
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/401444 , uj:33549
- Description: Abstract : In the recent past, there has been a great concern on the ever-increasing emergence of organic contaminants in the various environmental compartments, that pose great health concerns to humans and aquatic life. These organic pollutants have been ubiquitous in the environment for decades, however, they were not identifiable until the emergence of new and advanced analytical technologies. Therefore, the main objective of this study was to develop robust and efficient analytical and modelling techniques, for the extraction and analysis of selected multiclass organic contaminants from wastewater samples. This is because their analytical determination is very challenging due to their occurrence in trace levels (ng L-1 to μg L-1) in the environment. The analytical techniques comprise of optimization of both the sample preparation procedures and instrumental analysis for detection and quantification. Solid phase extraction (SPE), dispersive liquid-liquid microextraction (DLLME) and ultrasonic-assisted magnetic solid phase dispersive extraction (UA-MSPDE) were the selected sample preparation techniques used for the extraction and preconcentration of methylparaben, ethylparaben, propylparaben, ethoprofos, parathion methyl, azinphos methyl and chlorpyrifos in water samples. This was followed by instrumental analysis for their detection and quantification using liquid chromatography tandem mass spectrometry (LC-MS/MS). The developed analytical techniques were applied in real environmental samples obtained from different water treatment stages of a local wastewater treatment plant in Gauteng province, South Africa. Experimental factors that had an influence on the analytical response in terms on highest percentage recoveries were optimized using both univariate (one factor a time) and multivariate approach for all the experiments in this study. Multivariate optimization was accomplished using Statistica and Minitab software. The performance characteristics of the LC-MS/MS facilitated the determination of these organic contaminants at trace levels. Multiple reaction monitoring mode (MRM) was used for specific and sensitive targeted analysis, where the quadrupole analyzers were set at multiple ion frequencies for the specific analytes under investigation together with their product fragment ions. MRM is ideally suitable for trace level analysis of complex mixtures. Oasis HLB cartridges were found to be suitable for extraction of parabens giving satisfactory results. Vortex assisted dispersive liquid-liquid microextraction (VA-DLLME) was used for the extraction and enrichment of organophosphorus pesticides in wastewater samples. Selection of the appropriate organic solvent (extractant and disperser solvents) used for this method was of utmost importance and was performed using univariate optimization. v The results revealed chloroform to be the most suitable extractant solvent while acetone was the optimum disperser solvent. This was followed by the chemometric optimization of the independent variables that significantly affect the outcome of the analytical response. The organophosphorus compounds that were extracted in wastewater samples using this technique with satisfactory results were ethoprofos, parathion methyl and azinphos methyl. Also, a novel method was developed for the extraction and preconcentration of multiclass organic compounds (parabens and organophosphorus pesticides) using synthesized pristine carbon nanodots (CNDs) applied as SPE adsorbent. A comparison between the synthesized CNDs and commercial based SPE sorbent was analyzed. Two-level factorial design and response surface methodology based on central composite design were used for multivariate optimization of the experimental variables. Furthermore, the CNDs were also functionalized with magnetite. The magnetic CNDs were applied for the development of magnetic solid phase dispersive extraction method with ultrasonic dispersion for the simultaneous extraction of chlorpyrifos and triclosan in environmental water samples. This method offered a very rapid and simple extraction and preconcentration of these organic contaminants with satisfactory results. , Ph.D. (Chemistry)
- Full Text:
- Authors: Muckoya, Vallerie Akinyi
- Date: 2019
- Subjects: Organic water pollutants , Water quality management , Mass spectrometry , Sample preparation (Chemistry)
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/401444 , uj:33549
- Description: Abstract : In the recent past, there has been a great concern on the ever-increasing emergence of organic contaminants in the various environmental compartments, that pose great health concerns to humans and aquatic life. These organic pollutants have been ubiquitous in the environment for decades, however, they were not identifiable until the emergence of new and advanced analytical technologies. Therefore, the main objective of this study was to develop robust and efficient analytical and modelling techniques, for the extraction and analysis of selected multiclass organic contaminants from wastewater samples. This is because their analytical determination is very challenging due to their occurrence in trace levels (ng L-1 to μg L-1) in the environment. The analytical techniques comprise of optimization of both the sample preparation procedures and instrumental analysis for detection and quantification. Solid phase extraction (SPE), dispersive liquid-liquid microextraction (DLLME) and ultrasonic-assisted magnetic solid phase dispersive extraction (UA-MSPDE) were the selected sample preparation techniques used for the extraction and preconcentration of methylparaben, ethylparaben, propylparaben, ethoprofos, parathion methyl, azinphos methyl and chlorpyrifos in water samples. This was followed by instrumental analysis for their detection and quantification using liquid chromatography tandem mass spectrometry (LC-MS/MS). The developed analytical techniques were applied in real environmental samples obtained from different water treatment stages of a local wastewater treatment plant in Gauteng province, South Africa. Experimental factors that had an influence on the analytical response in terms on highest percentage recoveries were optimized using both univariate (one factor a time) and multivariate approach for all the experiments in this study. Multivariate optimization was accomplished using Statistica and Minitab software. The performance characteristics of the LC-MS/MS facilitated the determination of these organic contaminants at trace levels. Multiple reaction monitoring mode (MRM) was used for specific and sensitive targeted analysis, where the quadrupole analyzers were set at multiple ion frequencies for the specific analytes under investigation together with their product fragment ions. MRM is ideally suitable for trace level analysis of complex mixtures. Oasis HLB cartridges were found to be suitable for extraction of parabens giving satisfactory results. Vortex assisted dispersive liquid-liquid microextraction (VA-DLLME) was used for the extraction and enrichment of organophosphorus pesticides in wastewater samples. Selection of the appropriate organic solvent (extractant and disperser solvents) used for this method was of utmost importance and was performed using univariate optimization. v The results revealed chloroform to be the most suitable extractant solvent while acetone was the optimum disperser solvent. This was followed by the chemometric optimization of the independent variables that significantly affect the outcome of the analytical response. The organophosphorus compounds that were extracted in wastewater samples using this technique with satisfactory results were ethoprofos, parathion methyl and azinphos methyl. Also, a novel method was developed for the extraction and preconcentration of multiclass organic compounds (parabens and organophosphorus pesticides) using synthesized pristine carbon nanodots (CNDs) applied as SPE adsorbent. A comparison between the synthesized CNDs and commercial based SPE sorbent was analyzed. Two-level factorial design and response surface methodology based on central composite design were used for multivariate optimization of the experimental variables. Furthermore, the CNDs were also functionalized with magnetite. The magnetic CNDs were applied for the development of magnetic solid phase dispersive extraction method with ultrasonic dispersion for the simultaneous extraction of chlorpyrifos and triclosan in environmental water samples. This method offered a very rapid and simple extraction and preconcentration of these organic contaminants with satisfactory results. , Ph.D. (Chemistry)
- Full Text:
Fabrication, characterisation and assessment of ultrafiltration membranes incorporating catalytic Metal Organic Frameworks (MOFs) for water treatment process
- Authors: Moima, Johannes Thapelo
- Date: 2019
- Subjects: Water quality management , Water - Purification
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/292601 , uj:31800
- Description: Abstract: The scarcity of water is a serious global problem. Due to contamination, clean water sources are threatened on daily basis and the provision of safe and affordable water to the needs of people is becoming an impossible. Major water pollutants can be divided into pathogens and chemicals. The scarce fresh water available in South Africa is declining in quality due to destruction of river catchments and increase in pollution caused by urbanisation, energy use, damming of rivers, mining, deforestation, agriculture, wetlands destruction, industrialisation, and accidental water pollution. About 2% of totally produced dyes are released into the water systems as effluents. These dyes are capable of causing allergic dermatitis, cancer, skin irritation, and mutation. They are also teratogenic and poisonous to fish species, people, and microorganisms. . The PVDF/GO(Cu-tpa) composite membranes of different MOF concentration and wt% were prepared via phase inversion and characterised with FTIR, AFM, and SEM including surface morphology, cross sectional view, EDS and elemental mapping and their performance were tested on WCA, water uptake, pure water flux and decolourisation of dye at different concentrations. The synthesis of GO was achieved by modified Hammer’s method and the GO was used with Cu-tpa to synthesise the composite. PVDF was used as the base polymer, PVP as a pore forming agent, and NMP as a solvent in preparation of membranes containing different fillers. The functional groups within the membrane were analysed by FTIR, AFM was used for topography and roughness, WCA was used to investigate the hydrophilicity, the information about the adsorption capacity of membranes was achieved via water uptake experiments, and membrane flux was utilised to obtain the information about the permeation of the membrane towards pure water. SEM was used for for the analyses of cross sectional area, surface morphology, EDS and EDS elemental analysis. Two membranes out of six were found to have morphological defects due to systematic and random errors. In WCA, pure water flux, and water uptake, the PVDF membrane was found to be hydrophobic and PVDF/[GO(Cu-tpa)0.1]0.25 membrane was found to be hydrophilic, and for decolourisation of the dye, hydrophobic membranes performed better than hydrophilic membranes. , M.Sc. (Nanoscience)
- Full Text:
- Authors: Moima, Johannes Thapelo
- Date: 2019
- Subjects: Water quality management , Water - Purification
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/292601 , uj:31800
- Description: Abstract: The scarcity of water is a serious global problem. Due to contamination, clean water sources are threatened on daily basis and the provision of safe and affordable water to the needs of people is becoming an impossible. Major water pollutants can be divided into pathogens and chemicals. The scarce fresh water available in South Africa is declining in quality due to destruction of river catchments and increase in pollution caused by urbanisation, energy use, damming of rivers, mining, deforestation, agriculture, wetlands destruction, industrialisation, and accidental water pollution. About 2% of totally produced dyes are released into the water systems as effluents. These dyes are capable of causing allergic dermatitis, cancer, skin irritation, and mutation. They are also teratogenic and poisonous to fish species, people, and microorganisms. . The PVDF/GO(Cu-tpa) composite membranes of different MOF concentration and wt% were prepared via phase inversion and characterised with FTIR, AFM, and SEM including surface morphology, cross sectional view, EDS and elemental mapping and their performance were tested on WCA, water uptake, pure water flux and decolourisation of dye at different concentrations. The synthesis of GO was achieved by modified Hammer’s method and the GO was used with Cu-tpa to synthesise the composite. PVDF was used as the base polymer, PVP as a pore forming agent, and NMP as a solvent in preparation of membranes containing different fillers. The functional groups within the membrane were analysed by FTIR, AFM was used for topography and roughness, WCA was used to investigate the hydrophilicity, the information about the adsorption capacity of membranes was achieved via water uptake experiments, and membrane flux was utilised to obtain the information about the permeation of the membrane towards pure water. SEM was used for for the analyses of cross sectional area, surface morphology, EDS and EDS elemental analysis. Two membranes out of six were found to have morphological defects due to systematic and random errors. In WCA, pure water flux, and water uptake, the PVDF membrane was found to be hydrophobic and PVDF/[GO(Cu-tpa)0.1]0.25 membrane was found to be hydrophilic, and for decolourisation of the dye, hydrophobic membranes performed better than hydrophilic membranes. , M.Sc. (Nanoscience)
- Full Text:
Improved access to small community drinking water supply systems and its effect on the probability of bacterial infection posed by water in household drinking water containers
- Authors: Mokoena, Matodzi Michael
- Date: 2010-04-08T08:37:48Z
- Subjects: Water purification , Water quality management
- Type: Thesis
- Identifier: uj:6755 , http://hdl.handle.net/10210/3162
- Description: M. Tech. , The study assessed the risk of infection introduced by containers in which households collect water from different sources. The study area was in rural villages in the Vhembe region of the Limpopo Province. Each village had its own unique water sources consisting mainly of untreated ground waters and untreated surface waters. Randomly selected household members use their containers to collect water from these different sources. Two of the three villages received new small water supply systems within the study period, proving the villagers with water of good health-related microbial quality. The remaining village continued to use contaminated water from their untreated surface water sources. The water supply intervention in two of the three villages provided the opportunity to assess the impact these interventions would have on the risk of infection i.e. whether the risk could be reduced for the villagers no having access to good quality water. A customized quantitative microbial risk assessment was done based on the health-related quality of the water that people ingested before and after the intervention. This assessment was based on exposure of, consequence to and impact on an individual water consumer. Exposure included variables such as daily quantities of unheated drinking water consumed per individual (in litres) available at the point of use (in the dwelling) for ingestion, numbers of diarrhoeagenic E. coli (Dec) per litre in water sampled from containers derived from water samples positive for indicator E. coli and daily doses of DEc per litre ingested by an individual in the target population. Consequence was assessed by calculating the probability of infection per day from diarrhoeagenic E. coli for an individual and from there the annual infection per individual. The impact of the small water supply system was determined by assessing changes in annual individual risk of infection from before to after the interventions per village. In terms of daily water volumes consumed per individual, there were no significant differences in consumption amongst the three villages. At 1.26 ℓcd (at the upper limit of the 95% confidence interval) the consumption was slightly higher than the one litre suggested by WHO 2003. The container water collected from sources before the intervention in the two villages was significantly more contaminated by indicator E. coli (iEc) and diarrhoeagenic E. coli (DEc) than their container waters after the intervention. In terms of impact, the risk of infections was substantially reduced by the interventions. For Village 1 the risk of infection was reduced from 646 infections to 135 infections per 10,000 of the population. If these are converted to 10% as disease manifesting, then there could have been 65 cases of enteric disease attributable to water before the intervention, which was then reduced to 14 cases after the intervention. For Village 2 the population risk was reduced from 110 to 67 cases after the intervention. For Village 3 the population risk remained at 2,778 infections or 278 cases of enteric waterborne disease because of their continued use of untreated water. The study findings indicated that for Village 1, the population risk of infection would be 135 infections per 10,000, for Village 2 it would be 167 and for Village 3 - 234. If the hypothetical conversion rate of one case of enteric waterborne disease for every 10 infections of Howard et al. (2006) is used, then this would mean 14 cases of disease per 10,000 for the population for Village 1, 17 cases for Village 2 and 24 cases for Village 3. Relating this to the WHO (2003) suggestion of one case per 1,000 as an acceptable, it would mean 1.3 cases for Village 1, 1.7 for Village 2 and 2.4 for Village 3. For Village 1 the risk of contracting waterborne enteric disease was close to acceptable, but not at all acceptable for the other two villages, even for Village group 2 after the intervention. The water system in Village 2 failed often during the study which was probably the cause of the persistently higher risk of disease. It can be concluded that providing a well maintained small water supply system reduced the risk to and maintained it at an acceptable level. Table
- Full Text:
- Authors: Mokoena, Matodzi Michael
- Date: 2010-04-08T08:37:48Z
- Subjects: Water purification , Water quality management
- Type: Thesis
- Identifier: uj:6755 , http://hdl.handle.net/10210/3162
- Description: M. Tech. , The study assessed the risk of infection introduced by containers in which households collect water from different sources. The study area was in rural villages in the Vhembe region of the Limpopo Province. Each village had its own unique water sources consisting mainly of untreated ground waters and untreated surface waters. Randomly selected household members use their containers to collect water from these different sources. Two of the three villages received new small water supply systems within the study period, proving the villagers with water of good health-related microbial quality. The remaining village continued to use contaminated water from their untreated surface water sources. The water supply intervention in two of the three villages provided the opportunity to assess the impact these interventions would have on the risk of infection i.e. whether the risk could be reduced for the villagers no having access to good quality water. A customized quantitative microbial risk assessment was done based on the health-related quality of the water that people ingested before and after the intervention. This assessment was based on exposure of, consequence to and impact on an individual water consumer. Exposure included variables such as daily quantities of unheated drinking water consumed per individual (in litres) available at the point of use (in the dwelling) for ingestion, numbers of diarrhoeagenic E. coli (Dec) per litre in water sampled from containers derived from water samples positive for indicator E. coli and daily doses of DEc per litre ingested by an individual in the target population. Consequence was assessed by calculating the probability of infection per day from diarrhoeagenic E. coli for an individual and from there the annual infection per individual. The impact of the small water supply system was determined by assessing changes in annual individual risk of infection from before to after the interventions per village. In terms of daily water volumes consumed per individual, there were no significant differences in consumption amongst the three villages. At 1.26 ℓcd (at the upper limit of the 95% confidence interval) the consumption was slightly higher than the one litre suggested by WHO 2003. The container water collected from sources before the intervention in the two villages was significantly more contaminated by indicator E. coli (iEc) and diarrhoeagenic E. coli (DEc) than their container waters after the intervention. In terms of impact, the risk of infections was substantially reduced by the interventions. For Village 1 the risk of infection was reduced from 646 infections to 135 infections per 10,000 of the population. If these are converted to 10% as disease manifesting, then there could have been 65 cases of enteric disease attributable to water before the intervention, which was then reduced to 14 cases after the intervention. For Village 2 the population risk was reduced from 110 to 67 cases after the intervention. For Village 3 the population risk remained at 2,778 infections or 278 cases of enteric waterborne disease because of their continued use of untreated water. The study findings indicated that for Village 1, the population risk of infection would be 135 infections per 10,000, for Village 2 it would be 167 and for Village 3 - 234. If the hypothetical conversion rate of one case of enteric waterborne disease for every 10 infections of Howard et al. (2006) is used, then this would mean 14 cases of disease per 10,000 for the population for Village 1, 17 cases for Village 2 and 24 cases for Village 3. Relating this to the WHO (2003) suggestion of one case per 1,000 as an acceptable, it would mean 1.3 cases for Village 1, 1.7 for Village 2 and 2.4 for Village 3. For Village 1 the risk of contracting waterborne enteric disease was close to acceptable, but not at all acceptable for the other two villages, even for Village group 2 after the intervention. The water system in Village 2 failed often during the study which was probably the cause of the persistently higher risk of disease. It can be concluded that providing a well maintained small water supply system reduced the risk to and maintained it at an acceptable level. Table
- Full Text:
Infrastructure asset management practices on information management
- Authors: Magaga, Sihle
- Date: 2018
- Subjects: Infrastructure (Economics) - Management , Water quality management
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/393643 , uj:32577
- Description: Abstract: Infrastructure Asset Management (IAM) as a specialised field/discipline has gained prominence internationally over the past two decades as business entities attempt to improve the life span, efficiency and cost effective utilization of their assets. This is not surprising as infrastructure, including water infrastructure, is by its very nature generally expensive to build and maintain and is meant to perform effectively throughout its lifecycle, which on average spans over several decades (Alegre, 2010). Throughout the lifecycle of an asset, decisions need to be taken that relate to maintenance, technological refreshment (upgrades) and disposal of the operational asset. At the heart of this decision making and implementation of these decisions is technical information. In the year 2012 the organisation formally adopted asset management and as part of that process it undertook an exercise in which it evaluated its asset management practices. The exercise looked at 17 Key Performance Areas which if according to the measurement framework that was utilised, were at best practice levels, would indicate that the organisation was managing its assets well. One of the KPAs that was assessed was technical information management and it was found that the accuracy and availability of technical information in the organisation was between 50 – 70 %. Such relatively low levels of information and accuracy were impacting the effective management of the organisation’s assets. This study sought to establish the current state of information availability and accuracy, and outline the factors that influence the availability and accuracy of information. This in turn would give... , M.Phil. (Engineering Management)
- Full Text:
- Authors: Magaga, Sihle
- Date: 2018
- Subjects: Infrastructure (Economics) - Management , Water quality management
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/393643 , uj:32577
- Description: Abstract: Infrastructure Asset Management (IAM) as a specialised field/discipline has gained prominence internationally over the past two decades as business entities attempt to improve the life span, efficiency and cost effective utilization of their assets. This is not surprising as infrastructure, including water infrastructure, is by its very nature generally expensive to build and maintain and is meant to perform effectively throughout its lifecycle, which on average spans over several decades (Alegre, 2010). Throughout the lifecycle of an asset, decisions need to be taken that relate to maintenance, technological refreshment (upgrades) and disposal of the operational asset. At the heart of this decision making and implementation of these decisions is technical information. In the year 2012 the organisation formally adopted asset management and as part of that process it undertook an exercise in which it evaluated its asset management practices. The exercise looked at 17 Key Performance Areas which if according to the measurement framework that was utilised, were at best practice levels, would indicate that the organisation was managing its assets well. One of the KPAs that was assessed was technical information management and it was found that the accuracy and availability of technical information in the organisation was between 50 – 70 %. Such relatively low levels of information and accuracy were impacting the effective management of the organisation’s assets. This study sought to establish the current state of information availability and accuracy, and outline the factors that influence the availability and accuracy of information. This in turn would give... , M.Phil. (Engineering Management)
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Measuring water utility efficiency using fuzzy logic
- Eldidy, Nezar Abdelfattah Mohamed
- Authors: Eldidy, Nezar Abdelfattah Mohamed
- Date: 2012-11-06
- Subjects: Fuzzy logic , Water utilities - Evaluation , Fuzzy systems , Water quality measurement , Water quality management
- Type: Thesis
- Identifier: uj:7361 , http://hdl.handle.net/10210/8117
- Description: D.Ing. , Measuring the efficiency of water utilities has been a constant challenge to various stakeholders in the water sector. There are several factors that influence the efficiency of utilities. The following study examines the different factors and establishes a model to quantify the efficiency of water utilities using limited number of variables. It utilises Fuzzy Logic to develop the measurement model. The developed method can also be used to configure a new water utility for efficiency. In addition, the research highlights some possible imperfections in the water policies that can result in an inherent inefficiency of a water utility. The developed model can assist in setting ceiling levels for utility's water assets and labour, to ensure efficiency. The model is generic and can be applied to any country or community, and can be used to configure water utilities for the poor. The Model utilised "Matlab Fuzzy Tool Box student version 2009a" software as a tool to develop the Fuzzy Inference Engine for Utility Efficiency. The study is a contribution to the domain of knowledge of water engineering science.
- Full Text:
- Authors: Eldidy, Nezar Abdelfattah Mohamed
- Date: 2012-11-06
- Subjects: Fuzzy logic , Water utilities - Evaluation , Fuzzy systems , Water quality measurement , Water quality management
- Type: Thesis
- Identifier: uj:7361 , http://hdl.handle.net/10210/8117
- Description: D.Ing. , Measuring the efficiency of water utilities has been a constant challenge to various stakeholders in the water sector. There are several factors that influence the efficiency of utilities. The following study examines the different factors and establishes a model to quantify the efficiency of water utilities using limited number of variables. It utilises Fuzzy Logic to develop the measurement model. The developed method can also be used to configure a new water utility for efficiency. In addition, the research highlights some possible imperfections in the water policies that can result in an inherent inefficiency of a water utility. The developed model can assist in setting ceiling levels for utility's water assets and labour, to ensure efficiency. The model is generic and can be applied to any country or community, and can be used to configure water utilities for the poor. The Model utilised "Matlab Fuzzy Tool Box student version 2009a" software as a tool to develop the Fuzzy Inference Engine for Utility Efficiency. The study is a contribution to the domain of knowledge of water engineering science.
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Remote sensing of water quality in inland water bodies
- Authors: Mahlasi, Craig
- Date: 2017
- Subjects: Water quality - Remote sensing , Water quality management , Water quality - Evaluation , Water - Analysis
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/285086 , uj:30815
- Description: M.A. (Geography) , Abstract: Water is a scarce resource in South Africa and the world at large. The quality of freshwater systems in South Africa is deteriorating as a result of anthropogenic influences. To ensure the sustainable use of water resources, directives from various authorities have recognised the importance of promoting good water quality. Traditionally water quality assessments have relied on in-situ observations. These are relatively expensive, time-consuming and labour-intensive, resulting in spatially and temporally inadequate databases. There is a need for the implementation and integration of sophisticated technologies and methodologies in water quality monitoring programmes. Remote sensing techniques have been applied to characterising the quantity and quality, as well as to monitoring geographical distribution of aquatic environments. This dissertation aims to use remote sensing products and techniques in assessing and monitoring the quality of resources. The first objective of the dissertation was to explore the utility of hyperspectral and simulated multispectral data in discriminating water hyacinth from adjacent grass cover in the Hartbeespoort Dam of South Africa. Continuum-removal analysis was performed on the water hyacinth and grass reflectance spectra to quantify the absorption features of both water hyacinth and grass. Random Forest classification was used to discriminate water hyacinth from grass. The results indicated that the continuum-removal approach was able to characterise the absorption features in water hyacinth and grass spectra. The Random Forest classification method proved to be effective in discriminating water hyacinth from grass using all and key relevant wavelengths as well as simulated datasets. The second objective was to investigate the utility of Random Forest regression along with hyperspectral, simulated Landsat 8 Operational Land Imager (OLI) and actual Landsat 8 OLI datasets in estimating chlorophyll-a (chl-a) and turbidity based on in-situ sampling regime in the Hartbeespoort Dam of South Africa. Seventy in-situ samples of surface water were collected from the study site. Measurements of chl-a, turbidity and reflectance were taken from each sample using a hand-held spectrometer. The Random Forest regression method was used to build relationships between chl-a and a range of datasets including hyperspectral, simulated Landsat 8 OLI and actual Landsat 8 OLI. The results demonstrated the potential of...
- Full Text:
- Authors: Mahlasi, Craig
- Date: 2017
- Subjects: Water quality - Remote sensing , Water quality management , Water quality - Evaluation , Water - Analysis
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/285086 , uj:30815
- Description: M.A. (Geography) , Abstract: Water is a scarce resource in South Africa and the world at large. The quality of freshwater systems in South Africa is deteriorating as a result of anthropogenic influences. To ensure the sustainable use of water resources, directives from various authorities have recognised the importance of promoting good water quality. Traditionally water quality assessments have relied on in-situ observations. These are relatively expensive, time-consuming and labour-intensive, resulting in spatially and temporally inadequate databases. There is a need for the implementation and integration of sophisticated technologies and methodologies in water quality monitoring programmes. Remote sensing techniques have been applied to characterising the quantity and quality, as well as to monitoring geographical distribution of aquatic environments. This dissertation aims to use remote sensing products and techniques in assessing and monitoring the quality of resources. The first objective of the dissertation was to explore the utility of hyperspectral and simulated multispectral data in discriminating water hyacinth from adjacent grass cover in the Hartbeespoort Dam of South Africa. Continuum-removal analysis was performed on the water hyacinth and grass reflectance spectra to quantify the absorption features of both water hyacinth and grass. Random Forest classification was used to discriminate water hyacinth from grass. The results indicated that the continuum-removal approach was able to characterise the absorption features in water hyacinth and grass spectra. The Random Forest classification method proved to be effective in discriminating water hyacinth from grass using all and key relevant wavelengths as well as simulated datasets. The second objective was to investigate the utility of Random Forest regression along with hyperspectral, simulated Landsat 8 Operational Land Imager (OLI) and actual Landsat 8 OLI datasets in estimating chlorophyll-a (chl-a) and turbidity based on in-situ sampling regime in the Hartbeespoort Dam of South Africa. Seventy in-situ samples of surface water were collected from the study site. Measurements of chl-a, turbidity and reflectance were taken from each sample using a hand-held spectrometer. The Random Forest regression method was used to build relationships between chl-a and a range of datasets including hyperspectral, simulated Landsat 8 OLI and actual Landsat 8 OLI. The results demonstrated the potential of...
- Full Text:
Seasonal rainfall influences on main pollutants in the Vaal River barrage reservoir: a temporal-spatial perspective
- Authors: Ochse, Estie
- Date: 2009-04-30T10:05:48Z
- Subjects: Pollutants , Water pollution , Water quality management , Vaal River (South Africa)
- Type: Thesis
- Identifier: uj:8341 , http://hdl.handle.net/10210/2467
- Description: M.A. , South Africa is situated within a semi-arid part of the world which is characterised by high seasonal variability in terms of rainfall and runoff, with high evaporation rates. This causes streamflow to be relatively low for most of the year, with seasonal sporadic high flows. Further stress is applied to the water resource through population growth, increased urbanisation and industrial activities. The study area is considered to be the most populated of the Upper Vaal Water Management Area (WMA), which is the most important WMA in terms of economic productivity in South Africa. This research report focused on assessing the temporal and spatial variations of pollution between four different sampling points located in the Vaal Barrage Reservoir, which is located in the heart of the Upper Vaal WMA. The Vaal River Barrage Reservoir forms a 64 kilometres long water body with an estimated total storage capacity of 63 million litres of water. The four sampling points are V2 (Vaal River at Engelbrechts Drift Weir); VRB 24 (Vaal River Barrage at 24 km); VRB 37 (Vaal River Barrage at 37 km) and V17 (Vaal Barrage Reservoir Outlet). The aim of this research is to determine the type of physical and chemical pollutants within the Vaal River Barrage which currently poses the biggest problem to river health. The spatial and temporal differences of the pollutant loads are established and discussed. In addition, it is determined what the seasonal influence of rainfall has on the water quality measured at the four different sampling points. Chemical pollutants which currently pose the biggest threat in terms of water quality for the Vaal Barrage Reservoir are Phosphates, Electrical Conductivity and Sulphates. These three water quality variables do not comply with the minimum standards as set by Rand Water. The occurrence of these pollutants in the Vaal River can be explained by the vast inputs of return flow water from sewage treatment plants, underground mine water and discharge from industries. Microbiological factors were not taken into consideration for this dissertation, due to the unavailability of the data for most of the sampling sites for the majority of the study period. It was found that there are seasonal variations in terms of water quality at three sampling points: VRB24, VRB37 and V17. Sample point V17 had the highest inverse correlation for the three pollutants which pose the biggest threat to the health of the Vaal Barrage Reservoir water body. This implies that high seasonal variability occurs in the pollutant load at this sampling point. Sample point V2 had extremely low inverse correlation figures, which implies that rainfall has little or no impact on the level/concentration of a pollutant. This can be explained by two factors. Firstly the dilution effect which water released from the Vaal Dam has due to the close proximity to V2. Secondly because urban, mining and industrial activities are much less evident at this point, and subsequently return flows are less.
- Full Text:
- Authors: Ochse, Estie
- Date: 2009-04-30T10:05:48Z
- Subjects: Pollutants , Water pollution , Water quality management , Vaal River (South Africa)
- Type: Thesis
- Identifier: uj:8341 , http://hdl.handle.net/10210/2467
- Description: M.A. , South Africa is situated within a semi-arid part of the world which is characterised by high seasonal variability in terms of rainfall and runoff, with high evaporation rates. This causes streamflow to be relatively low for most of the year, with seasonal sporadic high flows. Further stress is applied to the water resource through population growth, increased urbanisation and industrial activities. The study area is considered to be the most populated of the Upper Vaal Water Management Area (WMA), which is the most important WMA in terms of economic productivity in South Africa. This research report focused on assessing the temporal and spatial variations of pollution between four different sampling points located in the Vaal Barrage Reservoir, which is located in the heart of the Upper Vaal WMA. The Vaal River Barrage Reservoir forms a 64 kilometres long water body with an estimated total storage capacity of 63 million litres of water. The four sampling points are V2 (Vaal River at Engelbrechts Drift Weir); VRB 24 (Vaal River Barrage at 24 km); VRB 37 (Vaal River Barrage at 37 km) and V17 (Vaal Barrage Reservoir Outlet). The aim of this research is to determine the type of physical and chemical pollutants within the Vaal River Barrage which currently poses the biggest problem to river health. The spatial and temporal differences of the pollutant loads are established and discussed. In addition, it is determined what the seasonal influence of rainfall has on the water quality measured at the four different sampling points. Chemical pollutants which currently pose the biggest threat in terms of water quality for the Vaal Barrage Reservoir are Phosphates, Electrical Conductivity and Sulphates. These three water quality variables do not comply with the minimum standards as set by Rand Water. The occurrence of these pollutants in the Vaal River can be explained by the vast inputs of return flow water from sewage treatment plants, underground mine water and discharge from industries. Microbiological factors were not taken into consideration for this dissertation, due to the unavailability of the data for most of the sampling sites for the majority of the study period. It was found that there are seasonal variations in terms of water quality at three sampling points: VRB24, VRB37 and V17. Sample point V17 had the highest inverse correlation for the three pollutants which pose the biggest threat to the health of the Vaal Barrage Reservoir water body. This implies that high seasonal variability occurs in the pollutant load at this sampling point. Sample point V2 had extremely low inverse correlation figures, which implies that rainfall has little or no impact on the level/concentration of a pollutant. This can be explained by two factors. Firstly the dilution effect which water released from the Vaal Dam has due to the close proximity to V2. Secondly because urban, mining and industrial activities are much less evident at this point, and subsequently return flows are less.
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The development of principles and procedures for the establishment of water quality objectives for aquatic systems and their application on the Jukskei River System, Gauteng
- Authors: Van Veelen, Martinus
- Date: 2008-10-16T05:50:24Z
- Subjects: Water quality management , Jukskei River (South Africa)
- Type: Thesis
- Identifier: http://ujcontent.uj.ac.za8080/10210/383311 , uj:12408 , http://hdl.handle.net/10210/1218
- Description: D.Phil. , Water quality management in South Africa changed drastically over the last 20 years, from focussing on effluent control to managing the water resource itself. This resulted in the promulgation of the National Water Act (Act 36 of 1998) which introduced amongst others the classification of water resources and the Reserve. The implementation of the Act is currently in process, and this requires the development of a number of "tools". One such a need is to develop a protocol to set water quality objectives for water resources that takes cognisance of both the classification and the Reserve. The move to manage water resources has also taken place in other countries such as the United Kingdom, the United States of America, The Netherlands and Australia. However, most of these countries do not have the same circumstances or the same approach to water quality management as South Africa. In most cases those countries have adopted single value water quality objectives that lead to an on/off assessment of the success of management actions that does not take full cognisance of the natural variability of water quality such as is experienced in South Africa. Water quality is not static and the effect on a user is a function of dose and exposure. In most cases users can recover from short term exposures to undesirable conditions, as long as these effects are still chronic and not acute. Water quality can therefore not be assessed by making use of a single value, but must be based on a description of the central tendency as well as extreme values. This assessment (ideal, acceptable, tolerable, unacceptable) of water quality should also be linked to management actions so that managers of water resources know where to focus the limited resources at their disposal. In this thesis a protocol is developed that can be used to determine water quality objectives that take into account the class of the water resource, as well as the Reserve. Together with this an assessment system is offered that allows managers to prioritise their actions. The protocol was applied to the Jukskei River Catchment, using data that was collected over a six year period. The protocol was found to be robust and yielded water quality objectives that can be used to focus attention on the most pressing problems. , Prof. G.J. Steyn Dr. H. H. du Preez
- Full Text:
- Authors: Van Veelen, Martinus
- Date: 2008-10-16T05:50:24Z
- Subjects: Water quality management , Jukskei River (South Africa)
- Type: Thesis
- Identifier: http://ujcontent.uj.ac.za8080/10210/383311 , uj:12408 , http://hdl.handle.net/10210/1218
- Description: D.Phil. , Water quality management in South Africa changed drastically over the last 20 years, from focussing on effluent control to managing the water resource itself. This resulted in the promulgation of the National Water Act (Act 36 of 1998) which introduced amongst others the classification of water resources and the Reserve. The implementation of the Act is currently in process, and this requires the development of a number of "tools". One such a need is to develop a protocol to set water quality objectives for water resources that takes cognisance of both the classification and the Reserve. The move to manage water resources has also taken place in other countries such as the United Kingdom, the United States of America, The Netherlands and Australia. However, most of these countries do not have the same circumstances or the same approach to water quality management as South Africa. In most cases those countries have adopted single value water quality objectives that lead to an on/off assessment of the success of management actions that does not take full cognisance of the natural variability of water quality such as is experienced in South Africa. Water quality is not static and the effect on a user is a function of dose and exposure. In most cases users can recover from short term exposures to undesirable conditions, as long as these effects are still chronic and not acute. Water quality can therefore not be assessed by making use of a single value, but must be based on a description of the central tendency as well as extreme values. This assessment (ideal, acceptable, tolerable, unacceptable) of water quality should also be linked to management actions so that managers of water resources know where to focus the limited resources at their disposal. In this thesis a protocol is developed that can be used to determine water quality objectives that take into account the class of the water resource, as well as the Reserve. Together with this an assessment system is offered that allows managers to prioritise their actions. The protocol was applied to the Jukskei River Catchment, using data that was collected over a six year period. The protocol was found to be robust and yielded water quality objectives that can be used to focus attention on the most pressing problems. , Prof. G.J. Steyn Dr. H. H. du Preez
- Full Text:
The impact of industrial effluences on water quality in the Waterval River catchment
- Authors: Nel, Selma
- Date: 2009-03-31T09:45:32Z
- Subjects: Water quality , Water quality management , Water pollution , Klipspruit River (South Africa)
- Type: Mini-Dissertation
- Identifier: uj:8278 , http://hdl.handle.net/10210/2387
- Description: M.A. , The goal of this study is to determine the water quality of the Klipspruit River over a six-year period, from 2000 to 2005. The Klipspruit lies within the sub-catchment area of the Waterval River, which in itself forms part of the Upper Vaal Catchment. The Klipspruit runs through the city of Secunda in Mpumalanga Province, South Africa, its catchment area providing two percent of the water to the Vaal Dam. In its turn, the Vaal Dam is the main raw water source for Rand Water that provides potable water to 10 million people in its 18 000 square kilometre service area. This study specifically focuses on the long-term trends of six selected water-quality parameters related to the effluent generated at the Sasol Secunda Industrial Complex (SSIC) during its coal-to-fuel operations. Certain physical, chemical and organic water-quality parameters of the Klipspruit were investigated on the basis of samples taken from three monitoring points in it. The water samples were analysed in terms of the water quality guidelines stipulated by the Department of Water Affairs and Forestry (DWAF), as well as the In-stream Water Quality Guidelines laid down by the Waterval River Catchment Management Agency. This was done to determine how industrial effluent impacts upon water quality in general and also how it affects water usage in other respects. The water-use categories considered in this study include aquatic ecosystems, domestic systems, livestock watering and irrigation systems. The results of conducting a regression analysis on the data collected from the monitoring points on the Klipspruit and assessing it in terms of the specifications laid down by the guidelines in question show that the respective concentrations of a number of water quality parameters in the upper part of the Klipspruit often exceed the ideal water quality levels. However, these concentration levels stabilize over time as the river continues to flow downstream. This is mainly due to the location of the first monitoring point which is close to the Sasol Secunda Industrial Complex (SSIC), where the effluent is generated, and also because the Secunda Sewage Treatment Plant is in the vicinity.
- Full Text:
- Authors: Nel, Selma
- Date: 2009-03-31T09:45:32Z
- Subjects: Water quality , Water quality management , Water pollution , Klipspruit River (South Africa)
- Type: Mini-Dissertation
- Identifier: uj:8278 , http://hdl.handle.net/10210/2387
- Description: M.A. , The goal of this study is to determine the water quality of the Klipspruit River over a six-year period, from 2000 to 2005. The Klipspruit lies within the sub-catchment area of the Waterval River, which in itself forms part of the Upper Vaal Catchment. The Klipspruit runs through the city of Secunda in Mpumalanga Province, South Africa, its catchment area providing two percent of the water to the Vaal Dam. In its turn, the Vaal Dam is the main raw water source for Rand Water that provides potable water to 10 million people in its 18 000 square kilometre service area. This study specifically focuses on the long-term trends of six selected water-quality parameters related to the effluent generated at the Sasol Secunda Industrial Complex (SSIC) during its coal-to-fuel operations. Certain physical, chemical and organic water-quality parameters of the Klipspruit were investigated on the basis of samples taken from three monitoring points in it. The water samples were analysed in terms of the water quality guidelines stipulated by the Department of Water Affairs and Forestry (DWAF), as well as the In-stream Water Quality Guidelines laid down by the Waterval River Catchment Management Agency. This was done to determine how industrial effluent impacts upon water quality in general and also how it affects water usage in other respects. The water-use categories considered in this study include aquatic ecosystems, domestic systems, livestock watering and irrigation systems. The results of conducting a regression analysis on the data collected from the monitoring points on the Klipspruit and assessing it in terms of the specifications laid down by the guidelines in question show that the respective concentrations of a number of water quality parameters in the upper part of the Klipspruit often exceed the ideal water quality levels. However, these concentration levels stabilize over time as the river continues to flow downstream. This is mainly due to the location of the first monitoring point which is close to the Sasol Secunda Industrial Complex (SSIC), where the effluent is generated, and also because the Secunda Sewage Treatment Plant is in the vicinity.
- Full Text:
The impacts of feedlot effluent on aquatic freshwater systems
- Authors: Jonker, Michiel-Nell
- Date: 2010-05-26T06:11:05Z
- Subjects: Effect of heavy metals on Clarias gariepinus , Water quality management , Freshwater ecology , Aquatic ecology , Growth hormone releasing factor
- Type: Thesis
- Identifier: uj:6834 , http://hdl.handle.net/10210/3267
- Description: M.Sc. , This study aims to assess the potential impacts of intense feedlot activity on the aquatic freshwater environment, with reference to three feedlots, ranging in production size and all situated in the upper Vaal catchment area. Field assessments were done over a high flow and low flow period, while controlled exposures were also done to quantify a potential stress reaction to growth hormone exposure (using Clarias gariepinus as test organism). It was ascertained that water quality variables contributing towards differences between upstream and downstream environmental conditions are NH4 concentrations pH and conductivity. Lead concentrations were also periodically higher downstream from feedlot activity, in comparison with upstream. Taking the sediment assimilation potential of growth hormones into consideration, it was determined that Feedlot C showed the highest assimilation potential, while Feedlot A reflected the lowest. Alterations on family level invertebrate community structures indicated a categorical decline in abundances and species richness at sites situated downstream from feedlots. However, some clear seasonal influences were also observed. Further community and diversity analyses reflected alterations in invertebrate community structures that were not reflected in SASS 5 scores. With regards to the biomarkers applied in this study, it was noted that there was a significant (p<0.05) difference in the cellular energy allocation (CEA) between control and hormone exposed groups. The total amount of energy available (Ea) increased significantly for test organisms exposed to Diethylstilbestrol (DES), while there was a significant increase in energy consumption (Ec) of test organisms exposed to Trenbolone acetate (TBA). In addition to CEA, metabolic profiling of blood plasma was also performed, which indicated a definite ordination in metabolic constituents after fifteen days of exposure. This was established by subjecting the data to principle component analysis (PCA), which accounted for 83 % variance observed. The impacts and biotic responses identified in this study were contextualised with known literature on the effects of feedlot activity and growth hormone exposure on the aquatic environment. Finally, conclusions were drawn and recommendations made with regard to improving feedlot operational activities. The results obtained in this study contribute towards an integrated framework for the environmental management of feedlot activities.
- Full Text:
- Authors: Jonker, Michiel-Nell
- Date: 2010-05-26T06:11:05Z
- Subjects: Effect of heavy metals on Clarias gariepinus , Water quality management , Freshwater ecology , Aquatic ecology , Growth hormone releasing factor
- Type: Thesis
- Identifier: uj:6834 , http://hdl.handle.net/10210/3267
- Description: M.Sc. , This study aims to assess the potential impacts of intense feedlot activity on the aquatic freshwater environment, with reference to three feedlots, ranging in production size and all situated in the upper Vaal catchment area. Field assessments were done over a high flow and low flow period, while controlled exposures were also done to quantify a potential stress reaction to growth hormone exposure (using Clarias gariepinus as test organism). It was ascertained that water quality variables contributing towards differences between upstream and downstream environmental conditions are NH4 concentrations pH and conductivity. Lead concentrations were also periodically higher downstream from feedlot activity, in comparison with upstream. Taking the sediment assimilation potential of growth hormones into consideration, it was determined that Feedlot C showed the highest assimilation potential, while Feedlot A reflected the lowest. Alterations on family level invertebrate community structures indicated a categorical decline in abundances and species richness at sites situated downstream from feedlots. However, some clear seasonal influences were also observed. Further community and diversity analyses reflected alterations in invertebrate community structures that were not reflected in SASS 5 scores. With regards to the biomarkers applied in this study, it was noted that there was a significant (p<0.05) difference in the cellular energy allocation (CEA) between control and hormone exposed groups. The total amount of energy available (Ea) increased significantly for test organisms exposed to Diethylstilbestrol (DES), while there was a significant increase in energy consumption (Ec) of test organisms exposed to Trenbolone acetate (TBA). In addition to CEA, metabolic profiling of blood plasma was also performed, which indicated a definite ordination in metabolic constituents after fifteen days of exposure. This was established by subjecting the data to principle component analysis (PCA), which accounted for 83 % variance observed. The impacts and biotic responses identified in this study were contextualised with known literature on the effects of feedlot activity and growth hormone exposure on the aquatic environment. Finally, conclusions were drawn and recommendations made with regard to improving feedlot operational activities. The results obtained in this study contribute towards an integrated framework for the environmental management of feedlot activities.
- Full Text:
The management role of the Johannesburg City Council in the Bosmont/Claremont catchment (Region 4)
- Authors: Kruger, Francois
- Date: 2009-02-05T07:09:55Z
- Subjects: Watersheds , Local government , Environmental management , Water quality management , Johannesburg (South Africa)
- Type: Thesis
- Identifier: uj:8071 , http://hdl.handle.net/10210/2001
- Description: M.Sc. , The goal of the study is to investigate the role that the Local Government of the City of Johannesburg must play in the environmentally degraded Bosmont/Claremont catchment. The problem in the past was that different divisions within the Council had different responsibilities and acted in isolation from each other with regard to catchment management. Strategies were developed in this study that can be adopted by the City Council of Johannesburg and be implemented in all the catchments within its jurisdiction by all parties concerned. If these strategies prove to be successful, other local governments can also adopt it and implement them in the management of their catchments. It is thus the challenge of these strategies to provide direction for catchment management in the City Council of Johannesburg.
- Full Text:
- Authors: Kruger, Francois
- Date: 2009-02-05T07:09:55Z
- Subjects: Watersheds , Local government , Environmental management , Water quality management , Johannesburg (South Africa)
- Type: Thesis
- Identifier: uj:8071 , http://hdl.handle.net/10210/2001
- Description: M.Sc. , The goal of the study is to investigate the role that the Local Government of the City of Johannesburg must play in the environmentally degraded Bosmont/Claremont catchment. The problem in the past was that different divisions within the Council had different responsibilities and acted in isolation from each other with regard to catchment management. Strategies were developed in this study that can be adopted by the City Council of Johannesburg and be implemented in all the catchments within its jurisdiction by all parties concerned. If these strategies prove to be successful, other local governments can also adopt it and implement them in the management of their catchments. It is thus the challenge of these strategies to provide direction for catchment management in the City Council of Johannesburg.
- Full Text:
The presence of stygobitic macroinvertebrates in karstic aquifers: a case study in the cradle of humankind world heritage site
- Authors: Tasaki, Sayomi
- Date: 2008-06-20T13:43:46Z
- Subjects: Effect of water quality on aquatic invertebrates , Ground water , Water quality management , Aquifers , Cradle of humankind world heritage site (South Africa)
- Type: Thesis
- Identifier: uj:3174 , http://hdl.handle.net/10210/658
- Description: Subterranean ecosystems are regarded as the most extensive biome on earth, comprising terrestrial and aquatic systems - the latter constituting freshwater, anchialine and marine systems. This system plays a key role in the distribution and storage of freshwater, once it contains 97% of the world’s total liquid freshwater (Chapter 1), which has been progressively explored in quality and amount. Initial observation of the subterranean environment began with speleological studies by the recognition of a typical fauna adapted to live inside caves. The first studies to provide information about aquatic subterranean fauna commenced in Slovenia, with the description of the Proteus aguinus by Laurenti in 1768. After an initial faunal classification by the Danish zoologist Schiödte (1849), the Austrian naturalist Schiner (1854) established the most commonly used classification for cave fauna and a great portion of modern research dealing with ecobilogy of aquatic subterranean fauna has mostly evolved from the European biospeleology (Chapters 1 and 3). Studies in biospeleology have made a significant contribution to the progressive knowledge in aquatic subterranean ecology, especially in those circumstances where the access of the underground through smaller voids (e.g. crevicular spaces) is not possible. Accessibility to the underground environment is in fact a negative factor that has led a large number of studies consider about subterranean fauna initially being limited to caves. Spatial constraint was (and still is) a limiting factor in accessing a diverse range of subsurface habitats, although during the last decade, modern research has been using advance technology as a tool to overcome the physical barriers to subterranean research. For a long time the classification of subterranean aquatic organisms was an unclear subject, with the classification subterranean fauna mostly related to terrestrial cave fauna (troglofauna). The classification system dealing with aquatic subterranean groups (stygofauna) is more recent. A few nomenclature schemes have been proposed to describe these relationships, based on morphological, behavioural, and ecological adaptations of animals to the underground life and their level of relationship with groundwater (Chapter 4). The prefix “stygo” is suggested as the most descriptive to refer ecologically to a group of animals related to groundwater habitats. Groundwater related fauna (stygofauna) is comprised by groups of animals encompassing aquatic surface, intermediate and subterranean habitats. They represent diverse group of animals that have different interactive relationships with the groundwater habitat. Some may transact between surface water and groundwater systems, while others spend the whole life cycle in the subterranean voids (Gibert et al., 1994). This transition zone between surface streams and groundwater is recognized as a critically important boundary or ecotone, constituted by a habitat that contains a reservoir of invertebrate fauna biodiversity. It is therefore from the study of karst systems that most information on groundwater ecobiology is resourced, once the open structure of most karsts terrains promotes a number of caves, streams, crevices, sinkholes, and springs to allow human access. Karst systems are well fractured because of the relation between the rock mass and the action of meteoric water, as well as the dissolution rate of calcium carbonate rocks that high. The latter increases with time, producing a terrain with a great drainage potential (Chapter 2). Once porosity is high and the flow of percolating water is fast, it allows good vagility for subterranean fauna and nutrients, as well as penetration of contaminants. In subterranean karsts, much water saturates some areas inside rock spaces. The saturation in the rock in turn promotes large water pockets, known as aquifers. When these groundwater aquifers are found to be interconnecting with the adjacent ecosystems, they became active eco-hydrological components, due to their key participation in the surface-groundwater continuum. Groundwater has different degrees of importance, depending on the available sources of surface water. In many countries it supplies a significant proportion of urban and rural drinking water, industrial, and agricultural. Yet, groundwater systems are “hidden”, difficult in access and to study (Chapter 4, 5 and 7), consequently the recognition of the groundwater aquifer as a natural resource that needs to be protected is largely ignored. Moreover, studies in the ecobiology and distribution of stygobitic invertebrates (Chapter 5), and the need to identify a frame of methods for quality assessment and the suitability of groundwater invertebrates as bioindicative elements, has not been developed (Chapter 6). Finally, strong management and public education programs are required to emphasize the need for a better understanding of the nature of groundwater resources, their participation and complexity (Chapter 8), with the conceptualization of the groundwater aquifer integrity as an ecosystem still receiving little attention in South Africa. , Dr. J.F. Durand Prof. G.J. Steyn
- Full Text:
- Authors: Tasaki, Sayomi
- Date: 2008-06-20T13:43:46Z
- Subjects: Effect of water quality on aquatic invertebrates , Ground water , Water quality management , Aquifers , Cradle of humankind world heritage site (South Africa)
- Type: Thesis
- Identifier: uj:3174 , http://hdl.handle.net/10210/658
- Description: Subterranean ecosystems are regarded as the most extensive biome on earth, comprising terrestrial and aquatic systems - the latter constituting freshwater, anchialine and marine systems. This system plays a key role in the distribution and storage of freshwater, once it contains 97% of the world’s total liquid freshwater (Chapter 1), which has been progressively explored in quality and amount. Initial observation of the subterranean environment began with speleological studies by the recognition of a typical fauna adapted to live inside caves. The first studies to provide information about aquatic subterranean fauna commenced in Slovenia, with the description of the Proteus aguinus by Laurenti in 1768. After an initial faunal classification by the Danish zoologist Schiödte (1849), the Austrian naturalist Schiner (1854) established the most commonly used classification for cave fauna and a great portion of modern research dealing with ecobilogy of aquatic subterranean fauna has mostly evolved from the European biospeleology (Chapters 1 and 3). Studies in biospeleology have made a significant contribution to the progressive knowledge in aquatic subterranean ecology, especially in those circumstances where the access of the underground through smaller voids (e.g. crevicular spaces) is not possible. Accessibility to the underground environment is in fact a negative factor that has led a large number of studies consider about subterranean fauna initially being limited to caves. Spatial constraint was (and still is) a limiting factor in accessing a diverse range of subsurface habitats, although during the last decade, modern research has been using advance technology as a tool to overcome the physical barriers to subterranean research. For a long time the classification of subterranean aquatic organisms was an unclear subject, with the classification subterranean fauna mostly related to terrestrial cave fauna (troglofauna). The classification system dealing with aquatic subterranean groups (stygofauna) is more recent. A few nomenclature schemes have been proposed to describe these relationships, based on morphological, behavioural, and ecological adaptations of animals to the underground life and their level of relationship with groundwater (Chapter 4). The prefix “stygo” is suggested as the most descriptive to refer ecologically to a group of animals related to groundwater habitats. Groundwater related fauna (stygofauna) is comprised by groups of animals encompassing aquatic surface, intermediate and subterranean habitats. They represent diverse group of animals that have different interactive relationships with the groundwater habitat. Some may transact between surface water and groundwater systems, while others spend the whole life cycle in the subterranean voids (Gibert et al., 1994). This transition zone between surface streams and groundwater is recognized as a critically important boundary or ecotone, constituted by a habitat that contains a reservoir of invertebrate fauna biodiversity. It is therefore from the study of karst systems that most information on groundwater ecobiology is resourced, once the open structure of most karsts terrains promotes a number of caves, streams, crevices, sinkholes, and springs to allow human access. Karst systems are well fractured because of the relation between the rock mass and the action of meteoric water, as well as the dissolution rate of calcium carbonate rocks that high. The latter increases with time, producing a terrain with a great drainage potential (Chapter 2). Once porosity is high and the flow of percolating water is fast, it allows good vagility for subterranean fauna and nutrients, as well as penetration of contaminants. In subterranean karsts, much water saturates some areas inside rock spaces. The saturation in the rock in turn promotes large water pockets, known as aquifers. When these groundwater aquifers are found to be interconnecting with the adjacent ecosystems, they became active eco-hydrological components, due to their key participation in the surface-groundwater continuum. Groundwater has different degrees of importance, depending on the available sources of surface water. In many countries it supplies a significant proportion of urban and rural drinking water, industrial, and agricultural. Yet, groundwater systems are “hidden”, difficult in access and to study (Chapter 4, 5 and 7), consequently the recognition of the groundwater aquifer as a natural resource that needs to be protected is largely ignored. Moreover, studies in the ecobiology and distribution of stygobitic invertebrates (Chapter 5), and the need to identify a frame of methods for quality assessment and the suitability of groundwater invertebrates as bioindicative elements, has not been developed (Chapter 6). Finally, strong management and public education programs are required to emphasize the need for a better understanding of the nature of groundwater resources, their participation and complexity (Chapter 8), with the conceptualization of the groundwater aquifer integrity as an ecosystem still receiving little attention in South Africa. , Dr. J.F. Durand Prof. G.J. Steyn
- Full Text:
Water quality management at Halfway on the Sishen-Saldanha rail
- Authors: Van der Schyff, Karlien
- Date: 2014-02-10
- Subjects: Water quality management - South Africa - Halfway Station , Water quality management
- Type: Thesis
- Identifier: uj:3743 , http://hdl.handle.net/10210/9121
- Description: M.Sc. (Geography) , Please refer to full text to view abstract
- Full Text:
- Authors: Van der Schyff, Karlien
- Date: 2014-02-10
- Subjects: Water quality management - South Africa - Halfway Station , Water quality management
- Type: Thesis
- Identifier: uj:3743 , http://hdl.handle.net/10210/9121
- Description: M.Sc. (Geography) , Please refer to full text to view abstract
- Full Text:
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