Estimating the willingness-to-pay for restoring indigenous vegetation at selected sites in South Africa
- Authors: Tessendorf, Sharon Erica
- Date: 2007
- Subjects: Water resources development -- South Africa , Water-supply -- South Africa , Alien plants -- South Africa , Restoration ecology -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8999 , http://hdl.handle.net/10948/617 , Water resources development -- South Africa , Water-supply -- South Africa , Alien plants -- South Africa , Restoration ecology -- South Africa
- Description: The Working for Water (WfW) Programme is a public works programme designed to clear South Africa of invasive alien vegetation and to restore lowwater consuming indigenous vegetation in the areas that have been cleared. Funds to clear alien invasives were initially secured on the basis that such a programme would increase water runoff, facilitate biodiversity and ecosystem functioning, and provide social benefits through job creation. The economic merits of the Programme, in terms of increased water yields, has been established in the Western Cape and KwaZulu-Natal, but questioned in the Eastern and Southern Cape. However, there are economic aspects of the studies carried out in the Eastern and Southern Cape that merit more attention than was given them; one of these being the issue of non-water benefits. Preliminary figures emanating from contingent valuation pilot studies conducted at six WfW projects sites indicated that one of these non-water benefits, namely the biodiversity and ecosystem resilience benefit, could be substantial. As such, the primary objective of the present study was to apply the contingent valuation method (CVM) to value people’s preference for indigenous vegetation. This value was intended to serve as a proxy for increased biodiversity and ecosystem resilience at three WfW sites. Despite the controversy surrounding the CVM, it has been found that it is a credible valuation tool. The CVM’s merits lie in its versatility and in the fact that it is the only method available which is capable of obtaining estimates of both nonuse and use values, thus making it applicable for valuing biodiversity. The primary aim of a CVM study is to determine an estimate of the total willingness-to-pay (WTP). In this study, the total WTP figure was calculated by multiplying the median WTP for the local WfW Programme by the total number of user households. The respective total WTP amounts are shown in Table 1. It was anticipated that respondents would be willing to pay more for the national WfW Programme, than for the less inclusive good (i.e. the local WfW Programme). The results correspond with this expectation at the Port Elizabeth and Underberg sites. However, due to strategic factors Worcester respondents were willing to pay more for the local WfW Programme than for the national Programme.
- Full Text:
- Date Issued: 2007
- Authors: Tessendorf, Sharon Erica
- Date: 2007
- Subjects: Water resources development -- South Africa , Water-supply -- South Africa , Alien plants -- South Africa , Restoration ecology -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:8999 , http://hdl.handle.net/10948/617 , Water resources development -- South Africa , Water-supply -- South Africa , Alien plants -- South Africa , Restoration ecology -- South Africa
- Description: The Working for Water (WfW) Programme is a public works programme designed to clear South Africa of invasive alien vegetation and to restore lowwater consuming indigenous vegetation in the areas that have been cleared. Funds to clear alien invasives were initially secured on the basis that such a programme would increase water runoff, facilitate biodiversity and ecosystem functioning, and provide social benefits through job creation. The economic merits of the Programme, in terms of increased water yields, has been established in the Western Cape and KwaZulu-Natal, but questioned in the Eastern and Southern Cape. However, there are economic aspects of the studies carried out in the Eastern and Southern Cape that merit more attention than was given them; one of these being the issue of non-water benefits. Preliminary figures emanating from contingent valuation pilot studies conducted at six WfW projects sites indicated that one of these non-water benefits, namely the biodiversity and ecosystem resilience benefit, could be substantial. As such, the primary objective of the present study was to apply the contingent valuation method (CVM) to value people’s preference for indigenous vegetation. This value was intended to serve as a proxy for increased biodiversity and ecosystem resilience at three WfW sites. Despite the controversy surrounding the CVM, it has been found that it is a credible valuation tool. The CVM’s merits lie in its versatility and in the fact that it is the only method available which is capable of obtaining estimates of both nonuse and use values, thus making it applicable for valuing biodiversity. The primary aim of a CVM study is to determine an estimate of the total willingness-to-pay (WTP). In this study, the total WTP figure was calculated by multiplying the median WTP for the local WfW Programme by the total number of user households. The respective total WTP amounts are shown in Table 1. It was anticipated that respondents would be willing to pay more for the national WfW Programme, than for the less inclusive good (i.e. the local WfW Programme). The results correspond with this expectation at the Port Elizabeth and Underberg sites. However, due to strategic factors Worcester respondents were willing to pay more for the local WfW Programme than for the national Programme.
- Full Text:
- Date Issued: 2007
Revised parameter estimation methods for the Pitman monthly rainfall-runoff model
- Authors: Kapangaziwiri, Evison
- Date: 2008
- Subjects: Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Hydrology -- Mathematical models , Water supply -- South Africa , Water resources development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6033 , http://hdl.handle.net/10962/d1006172 , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Hydrology -- Mathematical models , Water supply -- South Africa , Water resources development -- South Africa
- Description: In recent years, increased demands have been placed on hydrologists to find the most effective methods of making predictions of hydrologic variables in ungauged basins. A huge part of the southern African region is ungauged and, in gauged basins, the extent to which observed flows represent natural flows is unknown, given unquantified upstream activities. The need to exploit water resources for social and economic development, considered in the light of water scarcity forecasts for the region, makes the reliable quantification of water resources a priority. Contemporary approaches to the problem of hydrological prediction in ungauged basins in the region have relied heavily on calibration against a limited gauged streamflow database and somewhat subjective parameter regionalizations using areas of assumed hydrological similarity. The reliance of these approaches on limited historical records, often of dubious quality, introduces uncertainty in water resources decisions. Thus, it is necessary to develop methods of estimating model parameters that are less reliant on calibration. This thesis addresses the question of whether physical basin properties and the role they play in runoff generation processes can be used directly in the estimation of parameter values of the Pitman monthly rainfall-runoff model. A physically-based approach to estimating the soil moisture accounting and runoff parameters of a conceptual, monthly time-step rainfall-runoff model is proposed. The study investigates the physical meaning of the model parameters, establishes linkages between parameter values and basin physical properties and develops relationships and equations for estimating the parameters taking into account the spatial and temporal scales used in typical model applications. The estimationmethods are then tested in selected gauged basins in southern Africa and the results of model simulations evaluated against historical observed flows. The results of 71 basins chosen from the southern African region suggest that it is possible to directly estimate hydrologically relevant parameters for the Pitman model from physical basin attributes. For South Africa, the statistical and visual fit of the simulations using the revised parameters were at least as good as the current regional sets, albeit the parameter sets being different. In the other countries where no regionalized parameter sets currently exist, simulations were equally good. The availability, within the southern African region, of the appropriate physical basin data and the disparities in the spatial scales and the levels of detail of the data currently available were identified as potential sources of uncertainty. GIS and remote sensing technologies and a widespread use of this revised approach are expected to facilitate access to these data.
- Full Text:
- Date Issued: 2008
- Authors: Kapangaziwiri, Evison
- Date: 2008
- Subjects: Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Hydrology -- Mathematical models , Water supply -- South Africa , Water resources development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6033 , http://hdl.handle.net/10962/d1006172 , Rain and rainfall -- Mathematical models , Runoff -- Mathematical models , Hydrology -- Mathematical models , Water supply -- South Africa , Water resources development -- South Africa
- Description: In recent years, increased demands have been placed on hydrologists to find the most effective methods of making predictions of hydrologic variables in ungauged basins. A huge part of the southern African region is ungauged and, in gauged basins, the extent to which observed flows represent natural flows is unknown, given unquantified upstream activities. The need to exploit water resources for social and economic development, considered in the light of water scarcity forecasts for the region, makes the reliable quantification of water resources a priority. Contemporary approaches to the problem of hydrological prediction in ungauged basins in the region have relied heavily on calibration against a limited gauged streamflow database and somewhat subjective parameter regionalizations using areas of assumed hydrological similarity. The reliance of these approaches on limited historical records, often of dubious quality, introduces uncertainty in water resources decisions. Thus, it is necessary to develop methods of estimating model parameters that are less reliant on calibration. This thesis addresses the question of whether physical basin properties and the role they play in runoff generation processes can be used directly in the estimation of parameter values of the Pitman monthly rainfall-runoff model. A physically-based approach to estimating the soil moisture accounting and runoff parameters of a conceptual, monthly time-step rainfall-runoff model is proposed. The study investigates the physical meaning of the model parameters, establishes linkages between parameter values and basin physical properties and develops relationships and equations for estimating the parameters taking into account the spatial and temporal scales used in typical model applications. The estimationmethods are then tested in selected gauged basins in southern Africa and the results of model simulations evaluated against historical observed flows. The results of 71 basins chosen from the southern African region suggest that it is possible to directly estimate hydrologically relevant parameters for the Pitman model from physical basin attributes. For South Africa, the statistical and visual fit of the simulations using the revised parameters were at least as good as the current regional sets, albeit the parameter sets being different. In the other countries where no regionalized parameter sets currently exist, simulations were equally good. The availability, within the southern African region, of the appropriate physical basin data and the disparities in the spatial scales and the levels of detail of the data currently available were identified as potential sources of uncertainty. GIS and remote sensing technologies and a widespread use of this revised approach are expected to facilitate access to these data.
- Full Text:
- Date Issued: 2008
Understanding and modelling of surface and groundwater interactions
- Authors: Tanner, Jane Louise
- Date: 2014
- Subjects: Groundwater -- South Africa , Water-supply -- Management , Integrated water development , Hydrogeology , Water resources development -- South Africa , Water -- Analysis , Groundwater -- Management , Watersheds -- South Africa , Hydrologic models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6043 , http://hdl.handle.net/10962/d1012994
- Description: The connections between surface water and groundwater systems remain poorly understood in many catchments throughout the world and yet they are fundamental to effectively managing water resources. Managing water resources in an integrated manner is not straightforward, particularly if both resources are being utilised, and especially in those regions that suffer problems of data scarcity. This study explores some of the principle issues associated with understanding and practically modelling surface and groundwater interactions. In South Africa, there remains much controversy over the most appropriate type of integrated model to be used and the way forward in terms of the development of the discipline; part of the disagreement stems from the fact that we cannot validate models adequately. This is largely due to traditional forms of model testing having limited power as it is difficult to differentiate between the uncertainties within different model structures, different sets of alternative parameter values and in the input data used to run the model. While model structural uncertainties are important to consider, the uncertainty from input data error together with parameter estimation error are often more significant to the overall residual error, and essential to consider if we want to achieve reliable predictions for water resource decisions. While new philosophies and theories on modelling and results validation have been developed (Beven, 2002; Gupta et al., 2008), in many cases models are not only still being validated and compared using sparse and uncertain datasets, but also expected to produce reliable predictions based on the flawed data. The approach in this study is focused on fundamental understanding of hydrological systems rather than calibration based modelling and promotes the use of all the available 'hard' and 'soft' data together with thoughtful conceptual examination of the processes occurring in an environment to ensure as far as possible that a model is generating sensible results by simulating the correct processes. The first part of the thesis focuses on characterising the 'typical' interaction environments found in South Africa. It was found that many traditional perceptual models are not necessarily applicable to South African conditions, largely due to the relative importance of unsaturated zone processes and the complexity of the dominantly fractured rock environments. The interaction environments were categorised into four main 'types' of environment. These include karst, primary, fractured rock (secondary), and alluvial environments. Processes critical to Integrated Water Resource Management (IWRM) were defined within each interaction type as a guideline to setting a model up to realistically represent the dominant processes in the respective settings. The second part of the thesis addressed the application and evaluation of the modified Pitman model (Hughes, 2004), which allows for surface and groundwater interaction behaviour at the catchment scale to be simulated. The issue is whether, given the different sources of uncertainty in the modelling process, we can differentiate one conceptual flow path from another in trying to refine the understanding and consequently have more faith in model predictions. Seven example catchments were selected from around South Africa to assess whether reliable integrated assessments can be carried out given the existing data. Specific catchment perceptual models were used to identify the critical processes occurring in each setting and the Pitman model was assessed on whether it could represent them (structural uncertainty). The available knowledge of specific environments or catchments was then examined in an attempt to resolve the parameter uncertainty present within each catchment and ensure the subsequent model setup was correctly representing the process understanding as far as possible. The confidence in the quantitative results inevitably varied with the amount and quality of the data available. While the model was deemed to be robust based on the behavioural results obtained in the majority of the case studies, in many cases a quantitative validation of the outputs was just not possible based on the available data. In these cases, the model was judged on its ability to represent the conceptualisation of the processes occurring in the catchments. While the lack of appropriate data means there will always be considerable uncertainty surrounding model validation, it can be argued that improved process understanding in an environment can be used to validate model outcomes to a degree, by assessing whether a model is getting the right results for the right reasons. Many water resource decisions are still made without adequate account being taken of the uncertainties inherent in assessing the response of hydrological systems. Certainly, with all the possible sources of uncertainty in a data scarce country such as South Africa, pure calibration based modelling is unlikely to produce reliable information for water resource managers as it can produce the right results for the wrong reasons. Thus it becomes essential to incorporate conceptual thinking into the modelling process, so that at the very least we are able to conclude that a model generates estimates that are consistent with, and reflect, our understanding (however limited) of the catchment processes. It is fairly clear that achieving the optimum model of a hydrological system may be fraught with difficulty, if not impossible. This makes it very difficult from a practitioner's point of view to decide which model and uncertainty estimation method to use. According to Beven (2009), this may be a transitional problem and in the future it may become clearer as we learn more about how to estimate the uncertainties associated with hydrological systems. Until then, a better understanding of the fundamental and most critical hydrogeological processes should be used to critically test and improve model predictions as far as possible. A major focus of the study was to identify whether the modified Pitman model could provide a practical tool for water resource managers by reliably determining the available water resource. The incorporation of surface and groundwater interaction routines seems to have resulted in a more robust and realistic model of basin hydrology. The overall conclusion is that the model, although simplified, is capable of representing the catchment scale processes that occur under most South African conditions.
- Full Text:
- Date Issued: 2014
- Authors: Tanner, Jane Louise
- Date: 2014
- Subjects: Groundwater -- South Africa , Water-supply -- Management , Integrated water development , Hydrogeology , Water resources development -- South Africa , Water -- Analysis , Groundwater -- Management , Watersheds -- South Africa , Hydrologic models
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6043 , http://hdl.handle.net/10962/d1012994
- Description: The connections between surface water and groundwater systems remain poorly understood in many catchments throughout the world and yet they are fundamental to effectively managing water resources. Managing water resources in an integrated manner is not straightforward, particularly if both resources are being utilised, and especially in those regions that suffer problems of data scarcity. This study explores some of the principle issues associated with understanding and practically modelling surface and groundwater interactions. In South Africa, there remains much controversy over the most appropriate type of integrated model to be used and the way forward in terms of the development of the discipline; part of the disagreement stems from the fact that we cannot validate models adequately. This is largely due to traditional forms of model testing having limited power as it is difficult to differentiate between the uncertainties within different model structures, different sets of alternative parameter values and in the input data used to run the model. While model structural uncertainties are important to consider, the uncertainty from input data error together with parameter estimation error are often more significant to the overall residual error, and essential to consider if we want to achieve reliable predictions for water resource decisions. While new philosophies and theories on modelling and results validation have been developed (Beven, 2002; Gupta et al., 2008), in many cases models are not only still being validated and compared using sparse and uncertain datasets, but also expected to produce reliable predictions based on the flawed data. The approach in this study is focused on fundamental understanding of hydrological systems rather than calibration based modelling and promotes the use of all the available 'hard' and 'soft' data together with thoughtful conceptual examination of the processes occurring in an environment to ensure as far as possible that a model is generating sensible results by simulating the correct processes. The first part of the thesis focuses on characterising the 'typical' interaction environments found in South Africa. It was found that many traditional perceptual models are not necessarily applicable to South African conditions, largely due to the relative importance of unsaturated zone processes and the complexity of the dominantly fractured rock environments. The interaction environments were categorised into four main 'types' of environment. These include karst, primary, fractured rock (secondary), and alluvial environments. Processes critical to Integrated Water Resource Management (IWRM) were defined within each interaction type as a guideline to setting a model up to realistically represent the dominant processes in the respective settings. The second part of the thesis addressed the application and evaluation of the modified Pitman model (Hughes, 2004), which allows for surface and groundwater interaction behaviour at the catchment scale to be simulated. The issue is whether, given the different sources of uncertainty in the modelling process, we can differentiate one conceptual flow path from another in trying to refine the understanding and consequently have more faith in model predictions. Seven example catchments were selected from around South Africa to assess whether reliable integrated assessments can be carried out given the existing data. Specific catchment perceptual models were used to identify the critical processes occurring in each setting and the Pitman model was assessed on whether it could represent them (structural uncertainty). The available knowledge of specific environments or catchments was then examined in an attempt to resolve the parameter uncertainty present within each catchment and ensure the subsequent model setup was correctly representing the process understanding as far as possible. The confidence in the quantitative results inevitably varied with the amount and quality of the data available. While the model was deemed to be robust based on the behavioural results obtained in the majority of the case studies, in many cases a quantitative validation of the outputs was just not possible based on the available data. In these cases, the model was judged on its ability to represent the conceptualisation of the processes occurring in the catchments. While the lack of appropriate data means there will always be considerable uncertainty surrounding model validation, it can be argued that improved process understanding in an environment can be used to validate model outcomes to a degree, by assessing whether a model is getting the right results for the right reasons. Many water resource decisions are still made without adequate account being taken of the uncertainties inherent in assessing the response of hydrological systems. Certainly, with all the possible sources of uncertainty in a data scarce country such as South Africa, pure calibration based modelling is unlikely to produce reliable information for water resource managers as it can produce the right results for the wrong reasons. Thus it becomes essential to incorporate conceptual thinking into the modelling process, so that at the very least we are able to conclude that a model generates estimates that are consistent with, and reflect, our understanding (however limited) of the catchment processes. It is fairly clear that achieving the optimum model of a hydrological system may be fraught with difficulty, if not impossible. This makes it very difficult from a practitioner's point of view to decide which model and uncertainty estimation method to use. According to Beven (2009), this may be a transitional problem and in the future it may become clearer as we learn more about how to estimate the uncertainties associated with hydrological systems. Until then, a better understanding of the fundamental and most critical hydrogeological processes should be used to critically test and improve model predictions as far as possible. A major focus of the study was to identify whether the modified Pitman model could provide a practical tool for water resource managers by reliably determining the available water resource. The incorporation of surface and groundwater interaction routines seems to have resulted in a more robust and realistic model of basin hydrology. The overall conclusion is that the model, although simplified, is capable of representing the catchment scale processes that occur under most South African conditions.
- Full Text:
- Date Issued: 2014
The value of locally isolated freshwater micro-algae in toxicity testing for water resource management in South Africa
- Authors: Gola, Nontutuzelo Pearl
- Date: 2015
- Subjects: Microalgae -- South Africa , Toxicity testing , Water resources development -- South Africa , Aquatic habitats -- South Africa , Water -- Pollution -- Toxicology , Water quality management -- South Africa , Sewage disposal in rivers, lakes, etc. -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6049 , http://hdl.handle.net/10962/d1017873
- Description: The ecological position of micro-algae at the base of the aquatic food web makes them critical components of aquatic ecosystems. Their short generation time also makes them useful biological indicators because they respond quickly to changes in environmental condition, enabling timely identification and assessment of water quality changes. The inclusion of micro-algae as indicators in water resource regulation and management in South Africa has started recently, their more extensive use in biomonitoring and ecotoxicology programmes for water resource management would contribute to the South African policy if water resource protection. The standard algal growth inhibition assay with the species Pseudokirchneriella subcapitata is currently used for monitoring toxicity of in-stream and industrial wastewater discharges to freshwater micro-algae. The relevance of the data generated by standard toxicity bioassays has been questioned, since micro-algae in particular are extremely variable in their sensitivity to a range of contaminants and these standard species used may not occur in the local aquatic environment. As a result, international regulatory agencies, have recommended algal growth inhibition tests be changed from a single standard species to tests with a number of species. One recommendation, in addition to the use of standard toxicity tests, is the use of species isolated from the local environment which may be more relevant for assessing site specific impacts. This study investigated the value and application of locally isolated South African freshwater micro-algae in toxicity tests for water resource management and was carried out in three phases. The first phase involved isolating micro-algae from South African aquatic resources. Micro-algae suitable for toxicity testing were identified and selected using as set of criteria. Three (Scenedesmus bicaudatus, Chlorella sorokiniana and Chlorella vulgaris) out of eight successfully isolated species satisfied the prescribed selection criteria and these were selected as potential toxicity test species. The second phase focused on refining and adapting the existing algal toxicity test protocol (the algal growth inhibition assay) for use on the locally isolated algal species. The refinement of the test protocol was achieved by exposing the locally isolated species to reference toxicants in order to assess and compare their growth and sensitivity to the toxicants under the prescribed toxicity test conditions with that of the standard toxicity test species (Pseudokirchneriella subcapitata) and a commercial laboratory species (Chlorella protothecoides). During this phase, one of the three local species (Scenedesmus bicaudatus) was eliminated as a potential toxicity test species due to inconsistent growth. The third phase of the study involved assessing the sensitivity of the two remaining species (C. vulgaris and C. sorokiniana) to a range of toxicants (reference toxicants, salts, effluents and a herbicide) and comparing it to that of the standard toxicity test species P. subcapitata and C. protothecoides. The toxicants were selected based on their relative importance in the South African context, as well as the practicality of using these local micro-algae to routinely determine the impact of these toxicants on local aquatic resources. The growth of the four micro-algae was stimulated by the selected effluents. The standard toxicity test species P. subcapitata was ranked the most sensitive and of the four species to two reference toxicants and two inorganic salts. Chlorella sorokiniana was ranked the most sensitive of the three Chlorella species to two reference toxicants and two inorganic salts. The herbicide stimulated the growth of C. vulgaris while inhibiting the growth of the other species. Pseudokirchneriela subcapitata and C. sorokiniana showed high intra-specific variability in growth, which made it difficult to determine the effective concentrations of the herbicide and therefore compare the sensitivity of the species. This varied response of micro-algal species to toxicants may result in the biodiversity shifts in aquatic ecosystems, and also supports the recommendation of using a battery of different species to support more informed decisions in water resource management.
- Full Text:
- Date Issued: 2015
- Authors: Gola, Nontutuzelo Pearl
- Date: 2015
- Subjects: Microalgae -- South Africa , Toxicity testing , Water resources development -- South Africa , Aquatic habitats -- South Africa , Water -- Pollution -- Toxicology , Water quality management -- South Africa , Sewage disposal in rivers, lakes, etc. -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6049 , http://hdl.handle.net/10962/d1017873
- Description: The ecological position of micro-algae at the base of the aquatic food web makes them critical components of aquatic ecosystems. Their short generation time also makes them useful biological indicators because they respond quickly to changes in environmental condition, enabling timely identification and assessment of water quality changes. The inclusion of micro-algae as indicators in water resource regulation and management in South Africa has started recently, their more extensive use in biomonitoring and ecotoxicology programmes for water resource management would contribute to the South African policy if water resource protection. The standard algal growth inhibition assay with the species Pseudokirchneriella subcapitata is currently used for monitoring toxicity of in-stream and industrial wastewater discharges to freshwater micro-algae. The relevance of the data generated by standard toxicity bioassays has been questioned, since micro-algae in particular are extremely variable in their sensitivity to a range of contaminants and these standard species used may not occur in the local aquatic environment. As a result, international regulatory agencies, have recommended algal growth inhibition tests be changed from a single standard species to tests with a number of species. One recommendation, in addition to the use of standard toxicity tests, is the use of species isolated from the local environment which may be more relevant for assessing site specific impacts. This study investigated the value and application of locally isolated South African freshwater micro-algae in toxicity tests for water resource management and was carried out in three phases. The first phase involved isolating micro-algae from South African aquatic resources. Micro-algae suitable for toxicity testing were identified and selected using as set of criteria. Three (Scenedesmus bicaudatus, Chlorella sorokiniana and Chlorella vulgaris) out of eight successfully isolated species satisfied the prescribed selection criteria and these were selected as potential toxicity test species. The second phase focused on refining and adapting the existing algal toxicity test protocol (the algal growth inhibition assay) for use on the locally isolated algal species. The refinement of the test protocol was achieved by exposing the locally isolated species to reference toxicants in order to assess and compare their growth and sensitivity to the toxicants under the prescribed toxicity test conditions with that of the standard toxicity test species (Pseudokirchneriella subcapitata) and a commercial laboratory species (Chlorella protothecoides). During this phase, one of the three local species (Scenedesmus bicaudatus) was eliminated as a potential toxicity test species due to inconsistent growth. The third phase of the study involved assessing the sensitivity of the two remaining species (C. vulgaris and C. sorokiniana) to a range of toxicants (reference toxicants, salts, effluents and a herbicide) and comparing it to that of the standard toxicity test species P. subcapitata and C. protothecoides. The toxicants were selected based on their relative importance in the South African context, as well as the practicality of using these local micro-algae to routinely determine the impact of these toxicants on local aquatic resources. The growth of the four micro-algae was stimulated by the selected effluents. The standard toxicity test species P. subcapitata was ranked the most sensitive and of the four species to two reference toxicants and two inorganic salts. Chlorella sorokiniana was ranked the most sensitive of the three Chlorella species to two reference toxicants and two inorganic salts. The herbicide stimulated the growth of C. vulgaris while inhibiting the growth of the other species. Pseudokirchneriela subcapitata and C. sorokiniana showed high intra-specific variability in growth, which made it difficult to determine the effective concentrations of the herbicide and therefore compare the sensitivity of the species. This varied response of micro-algal species to toxicants may result in the biodiversity shifts in aquatic ecosystems, and also supports the recommendation of using a battery of different species to support more informed decisions in water resource management.
- Full Text:
- Date Issued: 2015
The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer
- Authors: Wright, Alan
- Date: 1992
- Subjects: Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4817 , http://hdl.handle.net/10962/d1005491 , Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
- Description: The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
- Full Text:
- Date Issued: 1992
- Authors: Wright, Alan
- Date: 1992
- Subjects: Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4817 , http://hdl.handle.net/10962/d1005491 , Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
- Description: The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
- Full Text:
- Date Issued: 1992
A sustainable water quality framework for South Africa towards 2050
- Authors: Osmond, Christopher John
- Date: 2015
- Subjects: Construction industry -- South Africa , Sustainable development -- South Africa , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3255 , vital:20417
- Description: There are a wide range of issues that stem from inadequate access to, and the unsustainable management of water resources, which can lead to ecological and human crises (Gleik, 1998: 571). With the increasing demand for clean water for drinking and sanitation, coupled with population growth, aging infrastructure, and climate change, many countries face a complex set of threats when dealing with their water resources and the management thereof (Environmental Protection Agency, 2012: 4). South Africa‟s challenges are no different, if current trends in water management continue and government does not intervene with what has been an unequal society even in terms of the division of water, it will continue to lose ground in its development and sustaining of water resources (Ukwandu, 2009: 24 - 30). “The objective of managing the quantity, quality and reliability of the nation‟s water resources is to achieve optimum, long-term, environmentally sustainable social and economic benefit for society from their use.” (Principle 7 of the National Water Policy, Department of Water Affairs and Forestry, 1997: 20). The primary objective of this research is to develop a framework for water management and sustainable development by utilising a Causal Layered Analysis (CLA) to develop strategies for innovation in South Africa towards 2050. New rules and regulations have been adopted by local municipal divisions in South Africa to promote sustainable, environmentally friendly buildings and methods. It is therefore the aim of the research to establish ways in which water can be harvested and saved in a simple and innovative yet sustainable manner. The complexity of erecting structures has also increased with some sustainable measures in water management taking place, however the water issues in South Africa continue to grow and cause concern. Government therefore plays a pivotal role in ensuring that water is managed sustainably at not only harvesting and infrastructure level but also re-cycling level, where simple innovative strategies can be adopted. This paper further seeks to highlight the positive and negative impacts of implementing water management methods and strategies that can be adopted.
- Full Text:
- Date Issued: 2015
- Authors: Osmond, Christopher John
- Date: 2015
- Subjects: Construction industry -- South Africa , Sustainable development -- South Africa , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3255 , vital:20417
- Description: There are a wide range of issues that stem from inadequate access to, and the unsustainable management of water resources, which can lead to ecological and human crises (Gleik, 1998: 571). With the increasing demand for clean water for drinking and sanitation, coupled with population growth, aging infrastructure, and climate change, many countries face a complex set of threats when dealing with their water resources and the management thereof (Environmental Protection Agency, 2012: 4). South Africa‟s challenges are no different, if current trends in water management continue and government does not intervene with what has been an unequal society even in terms of the division of water, it will continue to lose ground in its development and sustaining of water resources (Ukwandu, 2009: 24 - 30). “The objective of managing the quantity, quality and reliability of the nation‟s water resources is to achieve optimum, long-term, environmentally sustainable social and economic benefit for society from their use.” (Principle 7 of the National Water Policy, Department of Water Affairs and Forestry, 1997: 20). The primary objective of this research is to develop a framework for water management and sustainable development by utilising a Causal Layered Analysis (CLA) to develop strategies for innovation in South Africa towards 2050. New rules and regulations have been adopted by local municipal divisions in South Africa to promote sustainable, environmentally friendly buildings and methods. It is therefore the aim of the research to establish ways in which water can be harvested and saved in a simple and innovative yet sustainable manner. The complexity of erecting structures has also increased with some sustainable measures in water management taking place, however the water issues in South Africa continue to grow and cause concern. Government therefore plays a pivotal role in ensuring that water is managed sustainably at not only harvesting and infrastructure level but also re-cycling level, where simple innovative strategies can be adopted. This paper further seeks to highlight the positive and negative impacts of implementing water management methods and strategies that can be adopted.
- Full Text:
- Date Issued: 2015
Civil society engagement with water governance at a local government scale in South Africa
- Weaver, Matthew James Thanduxolo
- Authors: Weaver, Matthew James Thanduxolo
- Date: 2019
- Subjects: Government accountability -- South Africa , Civil Society -- South Africa , Political participation -- South Africa , Local government -- South Africa , Water supply -- Management , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/151316 , vital:39051
- Description: The South African state’s ideological commitment to a participatory approach to managing water resources and delivering services in a way that includes all stakeholders warrants critical analysis.Realising this ideological commitment has proved challenging, due largely to the complex historical, political, social, and environmental context of integrated water resource management (IWRM) in South Africa. The overarching aim of this study was to explore and expand the learning of civil societyparticipating in water governance processes at a local government scale. To address this aim a single, in-depth, four-year case study into civil society participation in water governance in the Makana Local Municipality in the Eastern Cape Province of South Africa was conducted between 2014 and 2018. The case study comprised two research phases. Both phases of the research were conducted using an adaptive transdisciplinary and participatory action research approach underpinned by General Complexity Theory. Located at the research-practice interface, the study sought to be transformative and advance both scientific research and societal goals. Qualitative research methods and inductive and deductive modes of inference were used to collect and analyse the data respectively. In the first phase of the study, a Communities of Practice theoretical framing was adopted to investigate the emergence, practice and learning of a civil society organisation (CSO), Water for Dignity (WfD), in response to household water service delivery issues in the municipality. This phase served to build an understanding of factors that enabled and constrained the practice of WfD in addressing local water service issues, and of their role as social learning agents in building water-related knowledge in their community. As participation with the first civil society organisation fragmented, the opportunity arose for local government, the National Department of Water and Sanitation and civil society to co-engage. This opened up the second phase of the research during which the role of a multi-stakeholder platform, the Makana Water Forum (MWF), in enabling democratic water governance was investigated. The MWF was South Africa’s first catchment management forum with an integrated water service and water resource management agenda. In this phase, the study drew on interventionist methodology, Change Laboratory, from Cultural Historical Activity Theory (CHAT) to 1) describe the historical development, composition and shared purpose of the MWF multi-activity system constellation; and to 2) guide participants through seven learning actions (expansive learning cycle) to identify, analyse, model and implement remedial actions to problematic aspects (contradictions) of the MWF practice. Participants of the Change Laboratory workshops built their individual and collective transformative agency (deliberate actions to transform a problematic situation) as they navigated the expansive learning process. The development of this agency was identified through a micro-analysis of agentive talk. The two phases served to advance the exploration of civil society participation from informal participation to address water issues, to formal participation in water governance processes at a local government scale. Findings from the first phase of the research revealed that dedicated and sustained support of partners with distributed expertise and the highly motivated core members of WfD enabled the practice and emergence of the civil society organisation. However, factors such as poor internal leadership, power dynamics between supporting partners, socio-economic constraints and a deeply embedded lack of agency were found to be key constraining factors to WfD’s practice. Findings revealed that learning at WfD team level occurred in four ways, through learning as belonging, learning as doing, learning as experiencing and learning as becoming. The WfD CSO was able to catalyse social learning related to personal water rights; and best practices for improving water quality and water conservation in their wider community of practice. Social learning was fostered mainly through structured citizen engagements offered by WfD. The research provides evidence that civil society organisations can play an important role in bridging water-related knowledge gaps and can foster active citizenship in South African communities. However, despite significant inputs of support and resources through the engaged transdisciplinary research process, the practice and learning outcomes of WfD had a marginal transformative impact on improving the citizen’s every-day water service experiences. Findings from the second phase of the study revealed the MWF to resemble a multi-activity system constellation with a multiple, partially overlapping. interests related to the management of water. The establishment, function and contradictions constraining the function of the MWF were influenced by past cycles of participatory water governance-related activity and practice at national and local scales. Through the Change Laboratory process, 25 contradictions were identified that appeared to constrain the ability of the MWF to enable inclusive and meaningful participatory water governance. Through a process of expansive learning, participants sought to overcome three sets of contradictions grouped as Problem Themes: lack of clear focus of the MWF; representation, representivity and nonattendance; and the MWF relationship with the Makana Local Municipality. Remedial actions modelled and those enacted have improved aspects of the function of the MWF (such as diversified modes of engagement and a more focussed agenda) but have only resulted in incremental shifts towards enabling improved participatory practice, most markedly in building a collaborative relationship and trust between the MWF members, municipal and government officials. The microanalysis of agentive talk revealed seven different expressions of transformative agency. Constraining socio-economic and political conditions and the limited capacity of the coordinating committee of the MWF hindered the development of transformative agency to the extent to which concrete actions were implemented. Findings further revealed that contextualising a Change Laboratory process within the adaptive cycle of a complex social-ecological system, and the particular opportunity context the system presents, could inform the enactment of agency and its potential impact on the transformation of the system. The intervention with the MWF was too short a process to clearly observe the effects of transformative actions on the sustainability of the Makana Local Municipality water system. However, long-chain transformative agency through the development of one-on-one engagements, learning journeys and a reflexive component to the MWF engagements could support transformative pathways to sustainability in the municipality and water management system. The study contributes in-depth insight into the key role of learning as a catalyst in transformative processes. Learning improves the collaborative and adaptive capacity of people, and therefore, water management institutions, to manage explicitly for the complexity inherent in “complex” socialecological systems. It provides empirical evidence as to what enables and constrains “real” participation and learning in grass-roots water governance processes in the context of a shifting national drive towards a more adaptive and developmental Integrated Water Resource Management approach. It further provides methodological contributions to 1) the application of the Change Laboratory method with multi-activity system constellations in developing world contexts and 2) value and limitations of extended and engaged transdisciplinary research. Lastly, it provides practical recommendations to the establishment and sustainable function of both community-based CSOs and multi-stakeholder platforms engaging in water governance processes.
- Full Text:
- Date Issued: 2019
- Authors: Weaver, Matthew James Thanduxolo
- Date: 2019
- Subjects: Government accountability -- South Africa , Civil Society -- South Africa , Political participation -- South Africa , Local government -- South Africa , Water supply -- Management , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/151316 , vital:39051
- Description: The South African state’s ideological commitment to a participatory approach to managing water resources and delivering services in a way that includes all stakeholders warrants critical analysis.Realising this ideological commitment has proved challenging, due largely to the complex historical, political, social, and environmental context of integrated water resource management (IWRM) in South Africa. The overarching aim of this study was to explore and expand the learning of civil societyparticipating in water governance processes at a local government scale. To address this aim a single, in-depth, four-year case study into civil society participation in water governance in the Makana Local Municipality in the Eastern Cape Province of South Africa was conducted between 2014 and 2018. The case study comprised two research phases. Both phases of the research were conducted using an adaptive transdisciplinary and participatory action research approach underpinned by General Complexity Theory. Located at the research-practice interface, the study sought to be transformative and advance both scientific research and societal goals. Qualitative research methods and inductive and deductive modes of inference were used to collect and analyse the data respectively. In the first phase of the study, a Communities of Practice theoretical framing was adopted to investigate the emergence, practice and learning of a civil society organisation (CSO), Water for Dignity (WfD), in response to household water service delivery issues in the municipality. This phase served to build an understanding of factors that enabled and constrained the practice of WfD in addressing local water service issues, and of their role as social learning agents in building water-related knowledge in their community. As participation with the first civil society organisation fragmented, the opportunity arose for local government, the National Department of Water and Sanitation and civil society to co-engage. This opened up the second phase of the research during which the role of a multi-stakeholder platform, the Makana Water Forum (MWF), in enabling democratic water governance was investigated. The MWF was South Africa’s first catchment management forum with an integrated water service and water resource management agenda. In this phase, the study drew on interventionist methodology, Change Laboratory, from Cultural Historical Activity Theory (CHAT) to 1) describe the historical development, composition and shared purpose of the MWF multi-activity system constellation; and to 2) guide participants through seven learning actions (expansive learning cycle) to identify, analyse, model and implement remedial actions to problematic aspects (contradictions) of the MWF practice. Participants of the Change Laboratory workshops built their individual and collective transformative agency (deliberate actions to transform a problematic situation) as they navigated the expansive learning process. The development of this agency was identified through a micro-analysis of agentive talk. The two phases served to advance the exploration of civil society participation from informal participation to address water issues, to formal participation in water governance processes at a local government scale. Findings from the first phase of the research revealed that dedicated and sustained support of partners with distributed expertise and the highly motivated core members of WfD enabled the practice and emergence of the civil society organisation. However, factors such as poor internal leadership, power dynamics between supporting partners, socio-economic constraints and a deeply embedded lack of agency were found to be key constraining factors to WfD’s practice. Findings revealed that learning at WfD team level occurred in four ways, through learning as belonging, learning as doing, learning as experiencing and learning as becoming. The WfD CSO was able to catalyse social learning related to personal water rights; and best practices for improving water quality and water conservation in their wider community of practice. Social learning was fostered mainly through structured citizen engagements offered by WfD. The research provides evidence that civil society organisations can play an important role in bridging water-related knowledge gaps and can foster active citizenship in South African communities. However, despite significant inputs of support and resources through the engaged transdisciplinary research process, the practice and learning outcomes of WfD had a marginal transformative impact on improving the citizen’s every-day water service experiences. Findings from the second phase of the study revealed the MWF to resemble a multi-activity system constellation with a multiple, partially overlapping. interests related to the management of water. The establishment, function and contradictions constraining the function of the MWF were influenced by past cycles of participatory water governance-related activity and practice at national and local scales. Through the Change Laboratory process, 25 contradictions were identified that appeared to constrain the ability of the MWF to enable inclusive and meaningful participatory water governance. Through a process of expansive learning, participants sought to overcome three sets of contradictions grouped as Problem Themes: lack of clear focus of the MWF; representation, representivity and nonattendance; and the MWF relationship with the Makana Local Municipality. Remedial actions modelled and those enacted have improved aspects of the function of the MWF (such as diversified modes of engagement and a more focussed agenda) but have only resulted in incremental shifts towards enabling improved participatory practice, most markedly in building a collaborative relationship and trust between the MWF members, municipal and government officials. The microanalysis of agentive talk revealed seven different expressions of transformative agency. Constraining socio-economic and political conditions and the limited capacity of the coordinating committee of the MWF hindered the development of transformative agency to the extent to which concrete actions were implemented. Findings further revealed that contextualising a Change Laboratory process within the adaptive cycle of a complex social-ecological system, and the particular opportunity context the system presents, could inform the enactment of agency and its potential impact on the transformation of the system. The intervention with the MWF was too short a process to clearly observe the effects of transformative actions on the sustainability of the Makana Local Municipality water system. However, long-chain transformative agency through the development of one-on-one engagements, learning journeys and a reflexive component to the MWF engagements could support transformative pathways to sustainability in the municipality and water management system. The study contributes in-depth insight into the key role of learning as a catalyst in transformative processes. Learning improves the collaborative and adaptive capacity of people, and therefore, water management institutions, to manage explicitly for the complexity inherent in “complex” socialecological systems. It provides empirical evidence as to what enables and constrains “real” participation and learning in grass-roots water governance processes in the context of a shifting national drive towards a more adaptive and developmental Integrated Water Resource Management approach. It further provides methodological contributions to 1) the application of the Change Laboratory method with multi-activity system constellations in developing world contexts and 2) value and limitations of extended and engaged transdisciplinary research. Lastly, it provides practical recommendations to the establishment and sustainable function of both community-based CSOs and multi-stakeholder platforms engaging in water governance processes.
- Full Text:
- Date Issued: 2019
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