Estimating rainfall and water balance over the Okavango River Basin for hydrological applications
- Wilk, J, Kniveton, D, Andersson, L, Layberry, R, Todd, M C, Hughes, Denis A
- Authors: Wilk, J , Kniveton, D , Andersson, L , Layberry, R , Todd, M C , Hughes, Denis A
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:7084 , http://hdl.handle.net/10962/d1012343 , http://dx.doi.org/10.1016/j.jhydrol.2006.04.049
- Description: A historical database for use in rainfall-runoff modeling of the Okavango River Basin in Southwest Africa is presented. The work has relevance for similar data-sparse regions. The parameters of main concern are rainfall and catchment water balance, which are key variables for subsequent studies of the hydrological impacts of development and climate change. Rainfall estimates are based on a combination of in situ gauges and satellite sources. Rain gauge measurements are most extensive from 1955 to 1972, after which they are drastically reduced due to the Angolan civil war. The sensitivity of the rainfall fields to spatial interpolation techniques and the density of gauges were evaluated. Satellite based rainfall estimates for the basin are developed for the period from 1991 onwards, based on the Tropical Rainfall Measuring Mission (TRMM) and Special Sensor Microwave Imager (SSM/I) datasets. The consistency between the gauges and satellite estimates was considered. A methodology was developed to allow calibration of the rainfall-runoff hydrological model against rain gauge data from 1960 to 1972, with the prerequisite that the model should be driven by satellite derived rainfall products from 1990 onwards. With the rain gauge data, addition of a single rainfall station (Longa) in regions where stations earlier were lacking was more important than the chosen interpolation method. Comparison of satellite and gauge rainfall outside the basin indicated that the satellite overestimates rainfall by 20%. A non-linear correction was derived by fitting the rainfall frequency characteristics to those of the historical rainfall data. This satellite rainfall dataset was found satisfactory when using the Pitman rainfall-runoff model (Hughes, D., Andersson, L., Wilk, J., Savenije, H.H.G., this issue. Regional calibration of the Pitman model for the Okavango River. Journal of Hydrology). Intensive monitoring in the region is recommended to increase accuracy of the comprehensive satellite rainfall estimate calibration procedure.
- Full Text:
- Date Issued: 2006
- Authors: Wilk, J , Kniveton, D , Andersson, L , Layberry, R , Todd, M C , Hughes, Denis A
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:7084 , http://hdl.handle.net/10962/d1012343 , http://dx.doi.org/10.1016/j.jhydrol.2006.04.049
- Description: A historical database for use in rainfall-runoff modeling of the Okavango River Basin in Southwest Africa is presented. The work has relevance for similar data-sparse regions. The parameters of main concern are rainfall and catchment water balance, which are key variables for subsequent studies of the hydrological impacts of development and climate change. Rainfall estimates are based on a combination of in situ gauges and satellite sources. Rain gauge measurements are most extensive from 1955 to 1972, after which they are drastically reduced due to the Angolan civil war. The sensitivity of the rainfall fields to spatial interpolation techniques and the density of gauges were evaluated. Satellite based rainfall estimates for the basin are developed for the period from 1991 onwards, based on the Tropical Rainfall Measuring Mission (TRMM) and Special Sensor Microwave Imager (SSM/I) datasets. The consistency between the gauges and satellite estimates was considered. A methodology was developed to allow calibration of the rainfall-runoff hydrological model against rain gauge data from 1960 to 1972, with the prerequisite that the model should be driven by satellite derived rainfall products from 1990 onwards. With the rain gauge data, addition of a single rainfall station (Longa) in regions where stations earlier were lacking was more important than the chosen interpolation method. Comparison of satellite and gauge rainfall outside the basin indicated that the satellite overestimates rainfall by 20%. A non-linear correction was derived by fitting the rainfall frequency characteristics to those of the historical rainfall data. This satellite rainfall dataset was found satisfactory when using the Pitman rainfall-runoff model (Hughes, D., Andersson, L., Wilk, J., Savenije, H.H.G., this issue. Regional calibration of the Pitman model for the Okavango River. Journal of Hydrology). Intensive monitoring in the region is recommended to increase accuracy of the comprehensive satellite rainfall estimate calibration procedure.
- Full Text:
- Date Issued: 2006
Estimation of small reservoir storage capacities in Limpopo River Basin using geographical information systems (GIS) and remotely sensed surface areas: case of Mzingwane catchment
- Sawunyama, Tendai, Senzanje, J, Mhizha, A
- Authors: Sawunyama, Tendai , Senzanje, J , Mhizha, A
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:7077 , http://hdl.handle.net/10962/d1009741
- Description: The current interest in small reservoirs stems mainly from their utilization for domestic use, livestock watering, fishing and irrigation. Rarely were small reservoirs considered in the water resources system even though they are important in water resource planning and management. The main limitation being lack of knowledge on small reservoir capacities, for the methodologies used to quantify physical parameters of reservoirs are costly, time consuming and laborious. To address this challenge an attempt has been made in this study to estimate small reservoir storage capacities using remotely sensed surface areas. A field study on 12 small reservoirs was carried out in Mzingwane catchment in Limpopo River Basin; Zimbabwe. The depths of water accompanied with their coordinates were measured; from which area and capacity were calculated for each reservoir using geographical information system based on data acquired from the field and that from satellite images. The output data was compared and a linear regression analysis was carried out to establish a power relationship between surface area and storage capacity of small reservoirs. The Pearson correlation analysis at 95% confidence interval indicated that the variances of the two surface areas (field area and image area) were not significantly different (p < 0.05). The findings from linear regression analysis (log capacity–log area) show that there exist a power relationship between remotely sensed surface areas (m^2) and storage capacities of reservoirs (m^3), with 95% variation of the storage capacity being explained by surface areas. The relationship can be used as a tool in decision-making processes in integrated water resources planning and management in the river basin. The applicability of the relationship to other catchments requires further research as well as investigating the impacts of small reservoirs in water resources available in the river basin by carrying out a hydrological modelling of the catchment.
- Full Text:
- Date Issued: 2006
- Authors: Sawunyama, Tendai , Senzanje, J , Mhizha, A
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:7077 , http://hdl.handle.net/10962/d1009741
- Description: The current interest in small reservoirs stems mainly from their utilization for domestic use, livestock watering, fishing and irrigation. Rarely were small reservoirs considered in the water resources system even though they are important in water resource planning and management. The main limitation being lack of knowledge on small reservoir capacities, for the methodologies used to quantify physical parameters of reservoirs are costly, time consuming and laborious. To address this challenge an attempt has been made in this study to estimate small reservoir storage capacities using remotely sensed surface areas. A field study on 12 small reservoirs was carried out in Mzingwane catchment in Limpopo River Basin; Zimbabwe. The depths of water accompanied with their coordinates were measured; from which area and capacity were calculated for each reservoir using geographical information system based on data acquired from the field and that from satellite images. The output data was compared and a linear regression analysis was carried out to establish a power relationship between surface area and storage capacity of small reservoirs. The Pearson correlation analysis at 95% confidence interval indicated that the variances of the two surface areas (field area and image area) were not significantly different (p < 0.05). The findings from linear regression analysis (log capacity–log area) show that there exist a power relationship between remotely sensed surface areas (m^2) and storage capacities of reservoirs (m^3), with 95% variation of the storage capacity being explained by surface areas. The relationship can be used as a tool in decision-making processes in integrated water resources planning and management in the river basin. The applicability of the relationship to other catchments requires further research as well as investigating the impacts of small reservoirs in water resources available in the river basin by carrying out a hydrological modelling of the catchment.
- Full Text:
- Date Issued: 2006
Ethnicity, not class? The 1929 Bulawayo faction fights reconsidered
- Authors: Msindo, Enocent
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6150 , http://hdl.handle.net/10962/d1006816 , http://dx.doi.org/10.1080/03057070600829419
- Description: From Christmas Eve of 1929 to the end of that year, Bulawayo was an ungovernable city marred by fights between Shona, on the one hand (perceived as a 'common enemy'), and forces that were predominantly Ndebele and groups sympathetic to them. A brilliant attempt to explain these clashes a generation ago, nevertheless falls short. This article seeks to revise the popular interpretation of this violence and re-contextualise it historically. A longer timeframe would give us an alternative view of the conflict. It also vindicates the ethnic interpretation of the violence that Phimister and van Onselen, concentrating on the then popular Marxist 'class struggle' paradigm, either minimised or failed to assess thoroughly.
- Full Text:
- Date Issued: 2006
- Authors: Msindo, Enocent
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6150 , http://hdl.handle.net/10962/d1006816 , http://dx.doi.org/10.1080/03057070600829419
- Description: From Christmas Eve of 1929 to the end of that year, Bulawayo was an ungovernable city marred by fights between Shona, on the one hand (perceived as a 'common enemy'), and forces that were predominantly Ndebele and groups sympathetic to them. A brilliant attempt to explain these clashes a generation ago, nevertheless falls short. This article seeks to revise the popular interpretation of this violence and re-contextualise it historically. A longer timeframe would give us an alternative view of the conflict. It also vindicates the ethnic interpretation of the violence that Phimister and van Onselen, concentrating on the then popular Marxist 'class struggle' paradigm, either minimised or failed to assess thoroughly.
- Full Text:
- Date Issued: 2006
Evaluating the extent to which Nelson Mandela Metropolitan University (NMMU) libraries meet student expectations
- Authors: Zhibing, Mu
- Date: 2006
- Subjects: Nelson Mandela Metropoliotan University. Library , Academic libraries -- South Africa -- Port Elizabeth -- Evaluation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9351 , http://hdl.handle.net/10948/648 , Nelson Mandela Metropoliotan University. Library , Academic libraries -- South Africa -- Port Elizabeth -- Evaluation
- Description: The failure to evaluate the service quality by comparing service expectations and service perceptions of students requires that the management of NMMU libraries identify the service expectations and service perceptions of students and measure the gaps between these service expectations and service perceptions of students. A literature review was conducted to explore the service expectations and service perceptions of students. An effective method (using the LibQUAL model) to evaluate the service quality of NMMU libraries based on the service expectations of students was described. Thereafter, a LibQUAL survey was used to collect the required empirical data from a convenience sample of 2 047 students enrolled at NMMU. The empirical findings showed that gaps existed between the service expectations and service perceptions of students at different campuses of NMMU. At different campuses of NMMU, the service expectations of students were not met in term of the service perceptions of the four dimensions (affect of service, library as place, information access and personal control) of the LibQUAL model. ii The study identified the gaps between the service expectations and service perceptions of students at different NMMU campuses and conclusions and recommendations based on these gaps were formulated. The management of the NMMU libraries needs to choose appropriate strategies to improve the quality of NMMU library services based on the service expectations of students.
- Full Text:
- Date Issued: 2006
- Authors: Zhibing, Mu
- Date: 2006
- Subjects: Nelson Mandela Metropoliotan University. Library , Academic libraries -- South Africa -- Port Elizabeth -- Evaluation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9351 , http://hdl.handle.net/10948/648 , Nelson Mandela Metropoliotan University. Library , Academic libraries -- South Africa -- Port Elizabeth -- Evaluation
- Description: The failure to evaluate the service quality by comparing service expectations and service perceptions of students requires that the management of NMMU libraries identify the service expectations and service perceptions of students and measure the gaps between these service expectations and service perceptions of students. A literature review was conducted to explore the service expectations and service perceptions of students. An effective method (using the LibQUAL model) to evaluate the service quality of NMMU libraries based on the service expectations of students was described. Thereafter, a LibQUAL survey was used to collect the required empirical data from a convenience sample of 2 047 students enrolled at NMMU. The empirical findings showed that gaps existed between the service expectations and service perceptions of students at different campuses of NMMU. At different campuses of NMMU, the service expectations of students were not met in term of the service perceptions of the four dimensions (affect of service, library as place, information access and personal control) of the LibQUAL model. ii The study identified the gaps between the service expectations and service perceptions of students at different NMMU campuses and conclusions and recommendations based on these gaps were formulated. The management of the NMMU libraries needs to choose appropriate strategies to improve the quality of NMMU library services based on the service expectations of students.
- Full Text:
- Date Issued: 2006
Evaluation of Bacillus thuringiensis Berliner as an alternative control of small hive beetles, Aethina tumida Murray (Coleoptera: Nitidulidae)
- Buchholz, S, Neumann, Peter, Neumann, K, Hepburn, H Randall
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
Evaluation of kinetic parameters of traps in thermoluminescence phosphors
- Ogundare, F O, Balogun, F A, Hussain, L
- Authors: Ogundare, F O , Balogun, F A , Hussain, L
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6798 , http://hdl.handle.net/10962/d1003924 , http://dx.doi.org/10.1016/j.radmeas.2006.06.014
- Description: A method for evaluating trap depth E, order of kinetics b and frequency factor s from a thermoluminescence (TL) glow peak has been developed. The method is based on using intensities and temperatures at any three points on the glow peak. Unlike similar techniques that provide no expression for frequency factor, the present formulation provides such an expression. The expression does not require knowledge of the temperature at which maximum intensity occurs, a parameter not usually known accurately from experimental glow peak data. For the method, it is found that use of points in the ascending part of the glow peak where the intensities are less than 10% maximum intensity gives parameter values closest to the true ones. Possible reasons for getting less accurate results when points are taken beyond this region are discussed. Values of the activation energy calculated using the present technique were always close to the true value. However, the frequency factor only approaches the true value as the dose given to the sample approaches saturation. When the three data points are selected in the initial-rise region, the equation for evaluating E in the method described in this paper becomes a two-point version of the initial-rise method. The advantage of the present technique over the initial-rise method is that it also gives b and hence s. The method is used to analyse the TL glow curve of a gamma-irradiated sample from Ijero-Ekiti, Nigeria.
- Full Text:
- Date Issued: 2006
- Authors: Ogundare, F O , Balogun, F A , Hussain, L
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6798 , http://hdl.handle.net/10962/d1003924 , http://dx.doi.org/10.1016/j.radmeas.2006.06.014
- Description: A method for evaluating trap depth E, order of kinetics b and frequency factor s from a thermoluminescence (TL) glow peak has been developed. The method is based on using intensities and temperatures at any three points on the glow peak. Unlike similar techniques that provide no expression for frequency factor, the present formulation provides such an expression. The expression does not require knowledge of the temperature at which maximum intensity occurs, a parameter not usually known accurately from experimental glow peak data. For the method, it is found that use of points in the ascending part of the glow peak where the intensities are less than 10% maximum intensity gives parameter values closest to the true ones. Possible reasons for getting less accurate results when points are taken beyond this region are discussed. Values of the activation energy calculated using the present technique were always close to the true value. However, the frequency factor only approaches the true value as the dose given to the sample approaches saturation. When the three data points are selected in the initial-rise region, the equation for evaluating E in the method described in this paper becomes a two-point version of the initial-rise method. The advantage of the present technique over the initial-rise method is that it also gives b and hence s. The method is used to analyse the TL glow curve of a gamma-irradiated sample from Ijero-Ekiti, Nigeria.
- Full Text:
- Date Issued: 2006
Evaluation of rate of swelling and erosion of verapamil (VRP) sustained-release matrix tablets
- Khamanga, Sandile M, Walker, Roderick B
- Authors: Khamanga, Sandile M , Walker, Roderick B
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184232 , vital:44192 , xlink:href="https://doi.org/10.1080/03639040600599822"
- Description: Tablets manufactured in-house were compared to a marketed sustained-release product of verapamil to investigate the rate of hydration, erosion, and drug-release mechanism by measuring the wet and subsequent dry weights of the products. Swelling and erosion rates depended on the polymer and granulating fluid used, which ultimately pointed to their permeability characteristics. Erosion rate of the marketed product was highest, which suggests that the gel layer that formed around these tablets was weak as opposed to the robust and resistant layers of test products. Anomalous and near zero-order transport mechanisms were dominant in tests and commercial product, respectively.
- Full Text:
- Date Issued: 2006
- Authors: Khamanga, Sandile M , Walker, Roderick B
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184232 , vital:44192 , xlink:href="https://doi.org/10.1080/03639040600599822"
- Description: Tablets manufactured in-house were compared to a marketed sustained-release product of verapamil to investigate the rate of hydration, erosion, and drug-release mechanism by measuring the wet and subsequent dry weights of the products. Swelling and erosion rates depended on the polymer and granulating fluid used, which ultimately pointed to their permeability characteristics. Erosion rate of the marketed product was highest, which suggests that the gel layer that formed around these tablets was weak as opposed to the robust and resistant layers of test products. Anomalous and near zero-order transport mechanisms were dominant in tests and commercial product, respectively.
- Full Text:
- Date Issued: 2006
Experiences of the Xhosa diabetic patient
- Authors: Ngamlana, Zodumo Princess
- Date: 2006
- Subjects: Diabetes -- Treatment -- South Africa , Diabetics -- Rehabilitation -- South Africa , Xhosa (African people) -- South Africa
- Language: English
- Type: Thesis , Masters , MCur
- Identifier: vital:10014 , http://hdl.handle.net/10948/465 , Diabetes -- Treatment -- South Africa , Diabetics -- Rehabilitation -- South Africa , Xhosa (African people) -- South Africa
- Description: This study will be focussing on the experiences of Xhosa-speaking patients with DM utilising the NMMM public hospitals complex. In the OPD patients are assessed and treated for all chronic conditions including DM, and patients are seen at monthly intervals or when necessary. The OPD serves the neighbouring black population from the surrounding townships as well as the informal settlements. The effects of urbanisation have resulted in this area having a semi–rural, semi-urban population that is mostly Xhosa speaking. The bulk of the population is unemployed, while others are living on a minimal income. Unemployment in the Eastern Cape ranges from 40% in rural areas, rising to 50 - 60% in the urban areas (Proposed aluminium Pechiney smelter within the Coega IDZ, 2002:4-8). In some homes there is no or little money to buy food, and even less to make use of a health service. Some people live on either a social grant for the elderly, a grant for young children or a disability grant and most people in this area have an income below the level at which payment of taxes for contribution to the economy is possible.
- Full Text:
- Date Issued: 2006
- Authors: Ngamlana, Zodumo Princess
- Date: 2006
- Subjects: Diabetes -- Treatment -- South Africa , Diabetics -- Rehabilitation -- South Africa , Xhosa (African people) -- South Africa
- Language: English
- Type: Thesis , Masters , MCur
- Identifier: vital:10014 , http://hdl.handle.net/10948/465 , Diabetes -- Treatment -- South Africa , Diabetics -- Rehabilitation -- South Africa , Xhosa (African people) -- South Africa
- Description: This study will be focussing on the experiences of Xhosa-speaking patients with DM utilising the NMMM public hospitals complex. In the OPD patients are assessed and treated for all chronic conditions including DM, and patients are seen at monthly intervals or when necessary. The OPD serves the neighbouring black population from the surrounding townships as well as the informal settlements. The effects of urbanisation have resulted in this area having a semi–rural, semi-urban population that is mostly Xhosa speaking. The bulk of the population is unemployed, while others are living on a minimal income. Unemployment in the Eastern Cape ranges from 40% in rural areas, rising to 50 - 60% in the urban areas (Proposed aluminium Pechiney smelter within the Coega IDZ, 2002:4-8). In some homes there is no or little money to buy food, and even less to make use of a health service. Some people live on either a social grant for the elderly, a grant for young children or a disability grant and most people in this area have an income below the level at which payment of taxes for contribution to the economy is possible.
- Full Text:
- Date Issued: 2006
Explaining South Africa's quiet diplomacy towards Zimbabwe since 2000: the dilemma of a pluralist middle power
- Authors: Gcoyi, Thembinkosi
- Date: 2006
- Subjects: Middle powers , Conflict management , Zimbabwe -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Zimbabwe , South Africa -- Politics and government -- 1994- , Zimbabwe -- Politics and government -- 1980-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2777 , http://hdl.handle.net/10962/d1002987 , Middle powers , Conflict management , Zimbabwe -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Zimbabwe , South Africa -- Politics and government -- 1994- , Zimbabwe -- Politics and government -- 1980-
- Description: This study is a contribution to the literature on South Africa's foreign policy since 2000-2004. It provides a theoretical framework within which South Africa's foreign policy should be understood. It attempts to explain the contradictions that have been apparent in South Africa's foreign policy by looking at the constraints inherent in South Africa's position as an emerging middle power. It argues that South Africa's pluralist inclinations are constrained by Africa's evolving multilateral forums and that South Africa's preference for such undermines the realization and achievement of her foreign policy principles and goals. It also argues that as a realist middle power, South Africa is constrained the ambivalence shown by the region towards her exercising leadership in the region. This is due to South Africa's history of destruction in Southern Africa in the 1980's. South Africa's quiet diplomacy towards Zimbabwe provides the focal point for the study. The study argues that it is not the case that South Africa is not concerned with human rights abuses in Zimbabwe. Instead, this concern has been expressed in ways that do not tarnish South Africa's own image in Africa. This has been done by engaging Zimbabweans through multilateral forums. This study concludes that this strategy failed to bring about resolution to the Zimbabwean crisis.
- Full Text:
- Date Issued: 2006
- Authors: Gcoyi, Thembinkosi
- Date: 2006
- Subjects: Middle powers , Conflict management , Zimbabwe -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Zimbabwe , South Africa -- Politics and government -- 1994- , Zimbabwe -- Politics and government -- 1980-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2777 , http://hdl.handle.net/10962/d1002987 , Middle powers , Conflict management , Zimbabwe -- Foreign relations -- South Africa , South Africa -- Foreign relations -- Zimbabwe , South Africa -- Politics and government -- 1994- , Zimbabwe -- Politics and government -- 1980-
- Description: This study is a contribution to the literature on South Africa's foreign policy since 2000-2004. It provides a theoretical framework within which South Africa's foreign policy should be understood. It attempts to explain the contradictions that have been apparent in South Africa's foreign policy by looking at the constraints inherent in South Africa's position as an emerging middle power. It argues that South Africa's pluralist inclinations are constrained by Africa's evolving multilateral forums and that South Africa's preference for such undermines the realization and achievement of her foreign policy principles and goals. It also argues that as a realist middle power, South Africa is constrained the ambivalence shown by the region towards her exercising leadership in the region. This is due to South Africa's history of destruction in Southern Africa in the 1980's. South Africa's quiet diplomacy towards Zimbabwe provides the focal point for the study. The study argues that it is not the case that South Africa is not concerned with human rights abuses in Zimbabwe. Instead, this concern has been expressed in ways that do not tarnish South Africa's own image in Africa. This has been done by engaging Zimbabweans through multilateral forums. This study concludes that this strategy failed to bring about resolution to the Zimbabwean crisis.
- Full Text:
- Date Issued: 2006
Exploitation status of infralittoral abalone (Haliotis midae) and alikreukel (Turbo sarmaticus) in the southern section of the Eastern Cape coast, South Africa
- Proudfoot, Lee-Anne, Kaehler, Sven, McGarry, Dylan K, Uppink, P A, Aereboe, Michael, Morris, K M
- Authors: Proudfoot, Lee-Anne , Kaehler, Sven , McGarry, Dylan K , Uppink, P A , Aereboe, Michael , Morris, K M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6915 , http://hdl.handle.net/10962/d1011878
- Description: Intertidal size-frequency distributions and densities for Haliotis midae and Turbo sarmaticus were examined at 10 sites experiencing varying pressure of human exploitation along the southern section of the Eastern Cape coast, South Africa. Target species' densities and maximum sizes were related both to the numbers of collectors on the shore and to indirect indicators of exploitation such as number of households in the vicinity and distance to the nearest beach access point. For both species, there was variation in density (P < 0.05) and size (P < 0.05) among sites, with densities ranging between 0.03-2.23 m^(-2) and 0.07-4.93 m^(-2) for H. midae and T. sarmaticus, respectively. Maximum sizes ranged between 49.4-153.5 mm (H. midae) and 28.3-104.4 mm (T. sarmaticus) shell length. Population parameters such as mean maximum size and total density were significantly negatively related to exploitation indicators for both species. In addition, densities of sexually mature and legal-size individuals of T. sarmaticus were significantly negatively related to the number of households. However, only for H. midae were densities of subadults significantly negatively related to the number of collectors, suggesting that reproduction of abalone may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tends to be localized near population centres, whereas H. midae is collected over a larger range of sites. Overall, T. sarmaticus is less affected by exploitation than H. midae.
- Full Text:
- Date Issued: 2006
- Authors: Proudfoot, Lee-Anne , Kaehler, Sven , McGarry, Dylan K , Uppink, P A , Aereboe, Michael , Morris, K M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6915 , http://hdl.handle.net/10962/d1011878
- Description: Intertidal size-frequency distributions and densities for Haliotis midae and Turbo sarmaticus were examined at 10 sites experiencing varying pressure of human exploitation along the southern section of the Eastern Cape coast, South Africa. Target species' densities and maximum sizes were related both to the numbers of collectors on the shore and to indirect indicators of exploitation such as number of households in the vicinity and distance to the nearest beach access point. For both species, there was variation in density (P < 0.05) and size (P < 0.05) among sites, with densities ranging between 0.03-2.23 m^(-2) and 0.07-4.93 m^(-2) for H. midae and T. sarmaticus, respectively. Maximum sizes ranged between 49.4-153.5 mm (H. midae) and 28.3-104.4 mm (T. sarmaticus) shell length. Population parameters such as mean maximum size and total density were significantly negatively related to exploitation indicators for both species. In addition, densities of sexually mature and legal-size individuals of T. sarmaticus were significantly negatively related to the number of households. However, only for H. midae were densities of subadults significantly negatively related to the number of collectors, suggesting that reproduction of abalone may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tends to be localized near population centres, whereas H. midae is collected over a larger range of sites. Overall, T. sarmaticus is less affected by exploitation than H. midae.
- Full Text:
- Date Issued: 2006
Exploring and describing depressogenic cognitive schema, levels of depression and hopelessness among depressed and non depressed adults
- Authors: Ahlfeldt, Alan
- Date: 2006
- Subjects: Depression, Mental -- South Africa , Depressed persons -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9845 , http://hdl.handle.net/10948/393 , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Description: The subject of mood disorders and in particular depression is pertinent with rapidly increasing incidences of depression and suicide a widespread phenomenon in the world today. In South Africa, the rates of depression are increasing steadily each year. Much research has been undertaken in the area of depression, with negative cognitive schema identified as a common factor, which increases an individual’s vulnerability or diathesis to depression and hopelessness. The primary aims of this research are to explore and describe the depressogenic cognitive schema of both a depressed as well as normal (nondepressed) individuals and identify the relationship these schema have to levels of depression and hopelessness. In order to achieve these objectives, three measures were administered, the Beck’s Depression Inventory, the Beck’s Hopelessness Scale and the Inferential Style Questionnaire. The research design is quantitative in nature and took the form of an exploratory-descriptive study. The researcher made use of frequency tests to identify frequencies of scores and descriptive statistics to identify the mean, range and standard deviations. T tests, a Pearson product- moment correlation coefficient and factorial analysis of variance (ANOVA) were also employed for statistical analysis within this research study. The findings of this research study identify that the depressed sample scored higher levels of depression, hopelessness and negative inferential style than that of the normal sample.
- Full Text:
- Date Issued: 2006
- Authors: Ahlfeldt, Alan
- Date: 2006
- Subjects: Depression, Mental -- South Africa , Depressed persons -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9845 , http://hdl.handle.net/10948/393 , Depression, Mental -- South Africa , Depressed persons -- South Africa
- Description: The subject of mood disorders and in particular depression is pertinent with rapidly increasing incidences of depression and suicide a widespread phenomenon in the world today. In South Africa, the rates of depression are increasing steadily each year. Much research has been undertaken in the area of depression, with negative cognitive schema identified as a common factor, which increases an individual’s vulnerability or diathesis to depression and hopelessness. The primary aims of this research are to explore and describe the depressogenic cognitive schema of both a depressed as well as normal (nondepressed) individuals and identify the relationship these schema have to levels of depression and hopelessness. In order to achieve these objectives, three measures were administered, the Beck’s Depression Inventory, the Beck’s Hopelessness Scale and the Inferential Style Questionnaire. The research design is quantitative in nature and took the form of an exploratory-descriptive study. The researcher made use of frequency tests to identify frequencies of scores and descriptive statistics to identify the mean, range and standard deviations. T tests, a Pearson product- moment correlation coefficient and factorial analysis of variance (ANOVA) were also employed for statistical analysis within this research study. The findings of this research study identify that the depressed sample scored higher levels of depression, hopelessness and negative inferential style than that of the normal sample.
- Full Text:
- Date Issued: 2006
Exploring employee morale at the Port Elizabeth plant of Cadbury (South Africa)
- Authors: Wolfaardt, Michelle
- Date: 2006
- Subjects: Cadbury Ltd , Chocolate industry -- South Africa -- Port Elizabeth , Employee morale , Job satisfaction , Performance standards , Employees -- Rating of , Personnel management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3093 , http://hdl.handle.net/10962/d1003129 , Cadbury Ltd , Chocolate industry -- South Africa -- Port Elizabeth , Employee morale , Job satisfaction , Performance standards , Employees -- Rating of , Personnel management
- Description: In the current business climate, performance is increasingly determined by how flexibly and effectively companies can utilize their human resources and this in tum, is influenced by employee morale. Morale refers to a state of psychosomatic health marked by an energetic, decisive resolution to achieve a given goal. When morale is low, employees may do what is required but do not have the energy to 'go the extra mile'. The importance of maintaining high morale is thus evident. The following project involved a study of morale in Cadbury's Port Elizabeth plant. Cadbury management was concerned about low morale following a recent merger with Bromor Foods. They thus wanted to assess: the state of current morale; any factors that may be influencing it; indicators of low morale (so that it may be monitored in the future) and finally, ways of addressing any existing morale issues. In order to achieve these aims, the researcher conducted interviews with various people to explore morale issues from employees' perspectives. She then sought confirmation for these views at the organizational level through the use of a survey. Statistical and thematic analyses showed morale to be low for middle managers and revealed a variety of indicators and influencing factors, as well as suggestions for addressing them. Despite the need to boost the sample size with convenience sampling, and thus, reduced representivity, the research was successful in answering the research aims.
- Full Text:
- Date Issued: 2006
- Authors: Wolfaardt, Michelle
- Date: 2006
- Subjects: Cadbury Ltd , Chocolate industry -- South Africa -- Port Elizabeth , Employee morale , Job satisfaction , Performance standards , Employees -- Rating of , Personnel management
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3093 , http://hdl.handle.net/10962/d1003129 , Cadbury Ltd , Chocolate industry -- South Africa -- Port Elizabeth , Employee morale , Job satisfaction , Performance standards , Employees -- Rating of , Personnel management
- Description: In the current business climate, performance is increasingly determined by how flexibly and effectively companies can utilize their human resources and this in tum, is influenced by employee morale. Morale refers to a state of psychosomatic health marked by an energetic, decisive resolution to achieve a given goal. When morale is low, employees may do what is required but do not have the energy to 'go the extra mile'. The importance of maintaining high morale is thus evident. The following project involved a study of morale in Cadbury's Port Elizabeth plant. Cadbury management was concerned about low morale following a recent merger with Bromor Foods. They thus wanted to assess: the state of current morale; any factors that may be influencing it; indicators of low morale (so that it may be monitored in the future) and finally, ways of addressing any existing morale issues. In order to achieve these aims, the researcher conducted interviews with various people to explore morale issues from employees' perspectives. She then sought confirmation for these views at the organizational level through the use of a survey. Statistical and thematic analyses showed morale to be low for middle managers and revealed a variety of indicators and influencing factors, as well as suggestions for addressing them. Despite the need to boost the sample size with convenience sampling, and thus, reduced representivity, the research was successful in answering the research aims.
- Full Text:
- Date Issued: 2006
Exploring the practical adequacy of the normative framework guiding South Africa’s National Curriculum Statement
- Schudel, Ingrid, Lotz-Sisitka, Heila
- Authors: Schudel, Ingrid , Lotz-Sisitka, Heila
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391193 , vital:68630 , xlink:href="https://www.tandfonline.com/doi/full/10.1080/13504620701284860"
- Description: This article examines the practical adequacy of the recent defining of a normative framework for the South African National Curriculum Statement that focuses on the relationship between human rights, social justice and a healthy environment. This politically framed and socially critical normative framework has developed in response to socio-political and socio-ecological histories in postapartheid curriculum transformation processes. The article critically considers the process of working with a normative framework in the defining of environmental education teaching and learning interactions, and seeks not only to explore the policy discourse critically, but also to explore what it is about the world that makes it work in different ways. Drawing on Sayer’s perspectives on the possibilities of enabling ‘situated universalism’ as a form of normative theory, and case-based data from a teacher professional development programme in the Makana District (where the authors live and work), the article probes the relationship between the establishment of a ‘universalising’ normative framework to guide national curriculum, and situated engagements with this framework in/as democratic process. In this process it questions whether educators should adopt the ‘norms’ as presented by society and simply universalize and implement them as prescribed by curriculum statements, or whether educators should adopt the strategies of postmodernists and reduce normative frameworks to relations of power situated in particular contexts.
- Full Text:
- Date Issued: 2006
- Authors: Schudel, Ingrid , Lotz-Sisitka, Heila
- Date: 2006
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391193 , vital:68630 , xlink:href="https://www.tandfonline.com/doi/full/10.1080/13504620701284860"
- Description: This article examines the practical adequacy of the recent defining of a normative framework for the South African National Curriculum Statement that focuses on the relationship between human rights, social justice and a healthy environment. This politically framed and socially critical normative framework has developed in response to socio-political and socio-ecological histories in postapartheid curriculum transformation processes. The article critically considers the process of working with a normative framework in the defining of environmental education teaching and learning interactions, and seeks not only to explore the policy discourse critically, but also to explore what it is about the world that makes it work in different ways. Drawing on Sayer’s perspectives on the possibilities of enabling ‘situated universalism’ as a form of normative theory, and case-based data from a teacher professional development programme in the Makana District (where the authors live and work), the article probes the relationship between the establishment of a ‘universalising’ normative framework to guide national curriculum, and situated engagements with this framework in/as democratic process. In this process it questions whether educators should adopt the ‘norms’ as presented by society and simply universalize and implement them as prescribed by curriculum statements, or whether educators should adopt the strategies of postmodernists and reduce normative frameworks to relations of power situated in particular contexts.
- Full Text:
- Date Issued: 2006
Factors influencing species richness, cover and composition of vegetation on Namaqualand quartz fields
- Authors: Van Tonder, Carlo
- Date: 2006
- Subjects: Plant diversity -- South Africa -- Namaqualand , Soil biology -- South Africa -- Namaqualand
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10752 , http://hdl.handle.net/10948/630 , Plant diversity -- South Africa -- Namaqualand , Soil biology -- South Africa -- Namaqualand
- Description: Quartz fields contribute significantly to plant diversity in the Succulent Karoo biome. They are distinctly different from surrounding habitats and have high levels of plant endemism. Biological soil crusts are features of quartz field soils and fulfill a vital function in that they stabilize soils. It is important for managers of nature reserves and agricultural rangelands to know what factors influence quartz field soils and vegetation. Both stakeholders could benefit from new information that would allow for informed decision-making regarding land-use on quartz fields. The present study took place in the Namaqua National Park that contains a significant proportion of the Riethuis-Wallekraal quartz fields phytochorion. The first part of the study aimed to understand whether certain land-use activities potentially destabilize quartz field soils, which might have possible ramifications for associated biological soil crusts and vegetation. It was followed by relating variation in soil stability with species richness, cover and species composition of quartz field vegetation. Overall, positions assumed to be impacted by land-use activities had less stable soils compared to positions assumed not be impacted. Soil stability had a significant influence on species richness and cover but to a lesser degree on species composition. Quartz field vegetation was significantly influenced by soil physical and chemical properties as well as location in the quartz fields landscape. The second part of the study aimed at understanding how species richness of isolated quartz outcrops is related to their size compared to that of a mainland body of quartz outcrops. No clear species-area relationships emerged from the study. There were significant differences between isolated outcrops and mainland outcrops in substrate and vegetation composition. Findings are discussed in relation to Island Biogeography Theory.
- Full Text:
- Date Issued: 2006
- Authors: Van Tonder, Carlo
- Date: 2006
- Subjects: Plant diversity -- South Africa -- Namaqualand , Soil biology -- South Africa -- Namaqualand
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10752 , http://hdl.handle.net/10948/630 , Plant diversity -- South Africa -- Namaqualand , Soil biology -- South Africa -- Namaqualand
- Description: Quartz fields contribute significantly to plant diversity in the Succulent Karoo biome. They are distinctly different from surrounding habitats and have high levels of plant endemism. Biological soil crusts are features of quartz field soils and fulfill a vital function in that they stabilize soils. It is important for managers of nature reserves and agricultural rangelands to know what factors influence quartz field soils and vegetation. Both stakeholders could benefit from new information that would allow for informed decision-making regarding land-use on quartz fields. The present study took place in the Namaqua National Park that contains a significant proportion of the Riethuis-Wallekraal quartz fields phytochorion. The first part of the study aimed to understand whether certain land-use activities potentially destabilize quartz field soils, which might have possible ramifications for associated biological soil crusts and vegetation. It was followed by relating variation in soil stability with species richness, cover and species composition of quartz field vegetation. Overall, positions assumed to be impacted by land-use activities had less stable soils compared to positions assumed not be impacted. Soil stability had a significant influence on species richness and cover but to a lesser degree on species composition. Quartz field vegetation was significantly influenced by soil physical and chemical properties as well as location in the quartz fields landscape. The second part of the study aimed at understanding how species richness of isolated quartz outcrops is related to their size compared to that of a mainland body of quartz outcrops. No clear species-area relationships emerged from the study. There were significant differences between isolated outcrops and mainland outcrops in substrate and vegetation composition. Findings are discussed in relation to Island Biogeography Theory.
- Full Text:
- Date Issued: 2006
Feeding dynamics and distribution of the hyperiid amphipod, Themisto gaudichaudii (Guérin, 1828) in the polar frontal zone, Southern Ocean
- Authors: Lange, Louise
- Date: 2006
- Subjects: Themisto gaudichaudii -- Antarctic Ocean , Hyperiidae -- Antarctic Ocean , Zooplankton -- Antarctic Ocean
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5696 , http://hdl.handle.net/10962/d1005382 , Themisto gaudichaudii -- Antarctic Ocean , Hyperiidae -- Antarctic Ocean , Zooplankton -- Antarctic Ocean
- Description: The population structure and feeding dynamics of the hyperiid amphipod, Themisto gaudichaudii, was investigated during two cruises of the South African National Antarctic Programme conducted in the Indian sector of the Polar Frontal Zone during austral autumn (April) 2004 and 2005. During the 2004 cruise the frontal features that delimit the PFZ converged to form a single distinctive feature. In 2005, the research cruise was conducted in the vicinity of a cold-core eddy which was spawned from the Antarctic Polar Front. Total mesozooplankton abundance and biomass during the 2004 study ranged from 55.19 to 860.57 ind. m⁻³, and from 2.60 to 38.42 mg dwt m⁻³, respectively. In 2005 the abundance and biomass ranged from 23.1 to 2160.64 ind. m⁻³, and from 0.76 to 35.16 mg dwt m⁻³, respectively. The mesozooplankton community was numerically dominated by copepods, pteropods, and ostracods during both surveys. The abundance and biomass of Themisto gaudichaudii in the region of investigation was < 0.2 ind. m⁻³ (range 0.01 to 0.15 ind. m⁻³) and < 0.06 mg dwt m⁻³ (range 0.02 to 0.06 mg dwt m⁻³) during 2004, while in 2005 the abundance and biomass of the amphipod ranged from < 0.01 to 0.2 ind. m⁻³ and < 0.01 to 0.04 mg dwt m⁻³, respectively. These values correspond to < 1% of the total mesozooplankton abundance and biomass during both surveys. T. gaudichaudii exhibited no significant spatial patterns in abundance, biomass and total length during both 2004 and 2005 (p > 0.05 in all cases). A key feature of the two investigations was the virtual absence of juveniles (total length < 15 mm) among the amphipod population, supporting the suggestion that they exhibit strong seasonal patterns in reproduction. Gut content analysis during both years indicated that for both the male and female amphipods’, copepods were the most prevalent prey species found in stomachs, followed by chaetognaths and pteropods. Results of electivity studies indicate that T. gaudichaudii is an opportunistic predator, generally feeding on the most abundant mesozooplankton prey. Results of in vitro incubations indicated that the total daily feeding rate of T. gaudichaudii during 2004 ranged from 11.45 to 20.90 ind. m⁻³ d⁻¹, which corresponds to between 0.12 and 1.64% of the total mesozooplankton standing stock. In 2005, the feeding rate ranged between 0.1 and 1.73% of the total mesozooplankton standing stock. The low predation impact of T. gaudichaudii during this study can be related to their low abundances and high interannual variability throughout the region of investigation.
- Full Text:
- Date Issued: 2006
- Authors: Lange, Louise
- Date: 2006
- Subjects: Themisto gaudichaudii -- Antarctic Ocean , Hyperiidae -- Antarctic Ocean , Zooplankton -- Antarctic Ocean
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5696 , http://hdl.handle.net/10962/d1005382 , Themisto gaudichaudii -- Antarctic Ocean , Hyperiidae -- Antarctic Ocean , Zooplankton -- Antarctic Ocean
- Description: The population structure and feeding dynamics of the hyperiid amphipod, Themisto gaudichaudii, was investigated during two cruises of the South African National Antarctic Programme conducted in the Indian sector of the Polar Frontal Zone during austral autumn (April) 2004 and 2005. During the 2004 cruise the frontal features that delimit the PFZ converged to form a single distinctive feature. In 2005, the research cruise was conducted in the vicinity of a cold-core eddy which was spawned from the Antarctic Polar Front. Total mesozooplankton abundance and biomass during the 2004 study ranged from 55.19 to 860.57 ind. m⁻³, and from 2.60 to 38.42 mg dwt m⁻³, respectively. In 2005 the abundance and biomass ranged from 23.1 to 2160.64 ind. m⁻³, and from 0.76 to 35.16 mg dwt m⁻³, respectively. The mesozooplankton community was numerically dominated by copepods, pteropods, and ostracods during both surveys. The abundance and biomass of Themisto gaudichaudii in the region of investigation was < 0.2 ind. m⁻³ (range 0.01 to 0.15 ind. m⁻³) and < 0.06 mg dwt m⁻³ (range 0.02 to 0.06 mg dwt m⁻³) during 2004, while in 2005 the abundance and biomass of the amphipod ranged from < 0.01 to 0.2 ind. m⁻³ and < 0.01 to 0.04 mg dwt m⁻³, respectively. These values correspond to < 1% of the total mesozooplankton abundance and biomass during both surveys. T. gaudichaudii exhibited no significant spatial patterns in abundance, biomass and total length during both 2004 and 2005 (p > 0.05 in all cases). A key feature of the two investigations was the virtual absence of juveniles (total length < 15 mm) among the amphipod population, supporting the suggestion that they exhibit strong seasonal patterns in reproduction. Gut content analysis during both years indicated that for both the male and female amphipods’, copepods were the most prevalent prey species found in stomachs, followed by chaetognaths and pteropods. Results of electivity studies indicate that T. gaudichaudii is an opportunistic predator, generally feeding on the most abundant mesozooplankton prey. Results of in vitro incubations indicated that the total daily feeding rate of T. gaudichaudii during 2004 ranged from 11.45 to 20.90 ind. m⁻³ d⁻¹, which corresponds to between 0.12 and 1.64% of the total mesozooplankton standing stock. In 2005, the feeding rate ranged between 0.1 and 1.73% of the total mesozooplankton standing stock. The low predation impact of T. gaudichaudii during this study can be related to their low abundances and high interannual variability throughout the region of investigation.
- Full Text:
- Date Issued: 2006
Feeding ecology, space use and habitat selection of elephants in two enclosed game reserves in the Eastern Cape Province, South Africa
- Authors: Roux, Candice
- Date: 2006
- Subjects: Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5699 , http://hdl.handle.net/10962/d1005385 , Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Description: The development of small (<300 km²), private game reserves has become a trend, not only in the Eastern Cape Province, but also elsewhere in South Africa as a result of a shift in land use practise from agriculture to ecotourism. The resultant re-introduction of elephants to many of these reserves has lead to management concerns because of the limited research on small reserves regarding their impact on the vegetation. In this study I assessed the space use, habitat selection, diet and impact of two elephant populations on the vegetation in the Eastern Cape Province between February 2004 and March 2005. Home range sizes were calculated using the kernel utilization distribution method. Home range sizes for elephants on Kwandwe were significantly larger during summer than winter (p<0.05). There was no significant difference between the home range sizes of the herds and males within a season and during summer the elephants utilized about 75 % of the reserve and only 54 % during winter. On Shamwari, the herd utilized about 92 % of the reserve during summer and 83 % during winter; while the males utilized 76 % of the reserve. Core areas for both elephant populations shrank from summer to winter and were concentrated around the permanent water sources on each reserve. Habitat selection was assessed using χ² tests and Bonferroni confidence intervals. On Kwandwe, there was a significant difference between observed and expected use of vegetation types (p<0.05) and karroid shrubland was strongly avoided by both herds during summer and winter. The preferred vegetation types of the males ranged from relatively open (short euphorbia thicket, bushclump karroid thicket and karroid shrubland) to completely open (old lands). On Shamwari, subtropical thicket, bontveld and montane grassland were avoided; while primary and secondary acacia thicket, riverine thicket and cultivated lands were preferred. The predominant vegetation type in the home ranges of herds on Kwandwe and Shamwari was subtropical thicket. The diet was assessed by direct observations over two seasons and dietary preferences were calculated. There was a significant difference in the frequency of occurrence of plants in the diet on the two reserves (p<0.05) and no significant effect of time of day or season (p>0.05). Seventeen woody plant species were utilized on Kwandwe and 23 species were utilized on Shamwari. Grass constituted a significantly greater percentage of the diet in summer than winter (p<0.05). Elephants on Kwandwe showed a selective preference for Ozoroa mucronata, Pappea capensis and Acacia karroo; while on Shamwari, A. karroo was selected. Transects were conducted in two different vegetation types on each reserve so as to assess the impact of elephant on the vegetation and damage scores were then calculated from these data. There was no significant effect of vegetation type or elephant density on mean damage scores in Kwandwe (p>0.05). Five hundred and seventy-eight plants were assessed in the subtropical thicket vegetation type and 225 plants were assessed in the savanna-type vegetation, with more than half the trees showing low levels of damage that could not only be attributed to elephants. Mean damage was highest for Portulacaria afra and Pappea capensis in subtropical thicket and for Rhus spp. in the savanna-type vegetation. On Shamwari, 408 plants were assessed in subtropical thicket and 215 in the savanna-type vegetation, with more than 70 % of trees showing low levels of damage. There was a significant effect of plant species and elephant density on the mean damage scores in subtropical thicket, with Aloe ferox showing more damage than the other plant species (p<0.01). In the savanna-type vegetation, A. karroo was the most severely damaged. Overall, damage was greater in the thicket vegetation type compared to the more open vegetation type on both reserves.
- Full Text:
- Date Issued: 2006
- Authors: Roux, Candice
- Date: 2006
- Subjects: Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5699 , http://hdl.handle.net/10962/d1005385 , Shamwari Game Reserve (South Africa) , Kwandwe Game Reserve (South Africa) , Elephants -- South Africa -- Eastern Cape , Elephants -- Ecology -- South Africa -- Eastern Cape , Elephants -- Feeding -- South Africa -- Eastern Cape , Elephants -- Nutrition -- South Africa -- Eastern Cape , Elephants -- Behavior -- South Africa -- Eastern Cape , Elephants -- Habitat -- South Africa -- Eastern Cape
- Description: The development of small (<300 km²), private game reserves has become a trend, not only in the Eastern Cape Province, but also elsewhere in South Africa as a result of a shift in land use practise from agriculture to ecotourism. The resultant re-introduction of elephants to many of these reserves has lead to management concerns because of the limited research on small reserves regarding their impact on the vegetation. In this study I assessed the space use, habitat selection, diet and impact of two elephant populations on the vegetation in the Eastern Cape Province between February 2004 and March 2005. Home range sizes were calculated using the kernel utilization distribution method. Home range sizes for elephants on Kwandwe were significantly larger during summer than winter (p<0.05). There was no significant difference between the home range sizes of the herds and males within a season and during summer the elephants utilized about 75 % of the reserve and only 54 % during winter. On Shamwari, the herd utilized about 92 % of the reserve during summer and 83 % during winter; while the males utilized 76 % of the reserve. Core areas for both elephant populations shrank from summer to winter and were concentrated around the permanent water sources on each reserve. Habitat selection was assessed using χ² tests and Bonferroni confidence intervals. On Kwandwe, there was a significant difference between observed and expected use of vegetation types (p<0.05) and karroid shrubland was strongly avoided by both herds during summer and winter. The preferred vegetation types of the males ranged from relatively open (short euphorbia thicket, bushclump karroid thicket and karroid shrubland) to completely open (old lands). On Shamwari, subtropical thicket, bontveld and montane grassland were avoided; while primary and secondary acacia thicket, riverine thicket and cultivated lands were preferred. The predominant vegetation type in the home ranges of herds on Kwandwe and Shamwari was subtropical thicket. The diet was assessed by direct observations over two seasons and dietary preferences were calculated. There was a significant difference in the frequency of occurrence of plants in the diet on the two reserves (p<0.05) and no significant effect of time of day or season (p>0.05). Seventeen woody plant species were utilized on Kwandwe and 23 species were utilized on Shamwari. Grass constituted a significantly greater percentage of the diet in summer than winter (p<0.05). Elephants on Kwandwe showed a selective preference for Ozoroa mucronata, Pappea capensis and Acacia karroo; while on Shamwari, A. karroo was selected. Transects were conducted in two different vegetation types on each reserve so as to assess the impact of elephant on the vegetation and damage scores were then calculated from these data. There was no significant effect of vegetation type or elephant density on mean damage scores in Kwandwe (p>0.05). Five hundred and seventy-eight plants were assessed in the subtropical thicket vegetation type and 225 plants were assessed in the savanna-type vegetation, with more than half the trees showing low levels of damage that could not only be attributed to elephants. Mean damage was highest for Portulacaria afra and Pappea capensis in subtropical thicket and for Rhus spp. in the savanna-type vegetation. On Shamwari, 408 plants were assessed in subtropical thicket and 215 in the savanna-type vegetation, with more than 70 % of trees showing low levels of damage. There was a significant effect of plant species and elephant density on the mean damage scores in subtropical thicket, with Aloe ferox showing more damage than the other plant species (p<0.01). In the savanna-type vegetation, A. karroo was the most severely damaged. Overall, damage was greater in the thicket vegetation type compared to the more open vegetation type on both reserves.
- Full Text:
- Date Issued: 2006
File integrity checking
- Authors: Motara, Yusuf Moosa
- Date: 2006
- Subjects: Linux , Operating systems (Computers) , Database design , Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4682 , http://hdl.handle.net/10962/d1007701 , Linux , Operating systems (Computers) , Database design , Computer security
- Description: This thesis looks at file execution as an attack vector that leads to the execution of unauthorized code. File integrity checking is examined as a means of removing this attack vector, and the design, implementation, and evaluation of a best-of-breed file integrity checker for the Linux operating system is undertaken. We conclude that the resultant file integrity checker does succeed in removing file execution as an attack vector, does so at a computational cost that is negligible, and displays innovative and useful features that are not currently found in any other Linux file integrity checker.
- Full Text:
- Date Issued: 2006
- Authors: Motara, Yusuf Moosa
- Date: 2006
- Subjects: Linux , Operating systems (Computers) , Database design , Computer security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4682 , http://hdl.handle.net/10962/d1007701 , Linux , Operating systems (Computers) , Database design , Computer security
- Description: This thesis looks at file execution as an attack vector that leads to the execution of unauthorized code. File integrity checking is examined as a means of removing this attack vector, and the design, implementation, and evaluation of a best-of-breed file integrity checker for the Linux operating system is undertaken. We conclude that the resultant file integrity checker does succeed in removing file execution as an attack vector, does so at a computational cost that is negligible, and displays innovative and useful features that are not currently found in any other Linux file integrity checker.
- Full Text:
- Date Issued: 2006
Financial reforms and interest rate spreads in the commercial banking sector in Kenya
- Authors: Munene, Daniel
- Date: 2006
- Subjects: Finance -- Kenya , Banks and banking -- Kenya , Economics -- Kenya , Interest rates -- Kenya , Economic development -- Kenya
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1070 , http://hdl.handle.net/10962/d1007711 , Finance -- Kenya , Banks and banking -- Kenya , Economics -- Kenya , Interest rates -- Kenya , Economic development -- Kenya
- Description: Financial reforms were a major component of structural adjustment programs deemed necessary for developing countries in the mid 1980s. These were not only meant to improve the sector, but would ultimately enhance economic growth and help in poverty alleviation. At the top of these reforms was financial liberalisation. Kenya, like many other sub-Saharan African countries, undertook financial liberalisation in 1991, one of the measures was decontrolling interest rates. With market driven interest rates in place it was assumed that there would be increased efficiency in bank lending, as well as growth in credit availability as deposits increased. A key indicator of this improved intermediation process would be a narrowing interest rates spread, that is, the margin between the deposit and lending rate. Paradoxically, however, the expected benefits of these reforms did not accrue to Kenya's banking sector. This study focuses on financial reforms and the spread of interest rates in Kenya's banking sector. Using a trend analysis, spanning the period before and after liberalisation, interest rates spread are shown to have escalated dramatically upwards after liberalisation. An analysis of three macroeconomic variables, namely, the exchange rate, inflation rate and economic growth offer little, or inconclusive evidence, that they were the main causes of the wide interest rate spread. In fact, the spread is closely linked to institutional/structural factors such as non-competitiveness in the banking sector, imprudent lending practices and poor and/or inadequate banking supervision. Policies for improving the institutional infrastructure and thus moderating the spreads are highlighted.
- Full Text:
- Date Issued: 2006
- Authors: Munene, Daniel
- Date: 2006
- Subjects: Finance -- Kenya , Banks and banking -- Kenya , Economics -- Kenya , Interest rates -- Kenya , Economic development -- Kenya
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1070 , http://hdl.handle.net/10962/d1007711 , Finance -- Kenya , Banks and banking -- Kenya , Economics -- Kenya , Interest rates -- Kenya , Economic development -- Kenya
- Description: Financial reforms were a major component of structural adjustment programs deemed necessary for developing countries in the mid 1980s. These were not only meant to improve the sector, but would ultimately enhance economic growth and help in poverty alleviation. At the top of these reforms was financial liberalisation. Kenya, like many other sub-Saharan African countries, undertook financial liberalisation in 1991, one of the measures was decontrolling interest rates. With market driven interest rates in place it was assumed that there would be increased efficiency in bank lending, as well as growth in credit availability as deposits increased. A key indicator of this improved intermediation process would be a narrowing interest rates spread, that is, the margin between the deposit and lending rate. Paradoxically, however, the expected benefits of these reforms did not accrue to Kenya's banking sector. This study focuses on financial reforms and the spread of interest rates in Kenya's banking sector. Using a trend analysis, spanning the period before and after liberalisation, interest rates spread are shown to have escalated dramatically upwards after liberalisation. An analysis of three macroeconomic variables, namely, the exchange rate, inflation rate and economic growth offer little, or inconclusive evidence, that they were the main causes of the wide interest rate spread. In fact, the spread is closely linked to institutional/structural factors such as non-competitiveness in the banking sector, imprudent lending practices and poor and/or inadequate banking supervision. Policies for improving the institutional infrastructure and thus moderating the spreads are highlighted.
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- Date Issued: 2006
Firewalls at Rhodes
- Authors: Siebörger, David
- Date: 2006
- Language: English
- Type: Conference paper
- Identifier: vital:6610 , http://hdl.handle.net/10962/d1009522
- Description: A presentation on the use of Internet Firewalls at Rhodes University. This formed part of the International Network for the Availability of Scientific Publications' Bandwidth Management and Optimisation Open Source Tools and Solutions project, being a series of workshops conducted throughout the developing world.
- Full Text:
- Date Issued: 2006
- Authors: Siebörger, David
- Date: 2006
- Language: English
- Type: Conference paper
- Identifier: vital:6610 , http://hdl.handle.net/10962/d1009522
- Description: A presentation on the use of Internet Firewalls at Rhodes University. This formed part of the International Network for the Availability of Scientific Publications' Bandwidth Management and Optimisation Open Source Tools and Solutions project, being a series of workshops conducted throughout the developing world.
- Full Text:
- Date Issued: 2006
Fishes of the deep demersal habitat at Ngazidja (Grand Comoro) Island, Western Indian Ocean
- Heemstra, P C, Hissmann, K, Fricke, H
- Authors: Heemstra, P C , Hissmann, K , Fricke, H
- Date: 2006
- Language: English
- Type: text , Article
- Identifier: vital:7128 , http://hdl.handle.net/10962/d1010638
- Description: Underwater observations of the coelacanth, Latimeria chalumnae Smith, 1939, from a research submersible provided opportunities to study the deep demersal fish fauna at the Comoro Islands. The demersal habitat in depths of 150–400 m at the volcanic island of Ngazidja is low in fish diversity and biomass, compared with the shallow-water coral reef habitat of Ngazidja or the deep demersal habitats of other localities in the Indo-Pacific region. The resident deep demersal fish fauna at Ngazidja is dominated by the coelacanth, an ancient predator that is specially adapted for this low-energy environment. Other large fish predators are scarce in this environment, because of the heavy fishing pressure from local fishermen. Eighty-nine fish taxa (including 65 recognizable species) were recorded from videotapes, photographs, visual observations, fishermen’s catches and ancillary attempts to sample the fish fauna with baited fish traps, gill nets, and hook and line. Although no coelacanth feeding events were seen, seven fish species are known from coelacanth stomach contents, and 64 other fish species in this habitat are considered potential prey of this dominant predator.
- Full Text:
- Date Issued: 2006
- Authors: Heemstra, P C , Hissmann, K , Fricke, H
- Date: 2006
- Language: English
- Type: text , Article
- Identifier: vital:7128 , http://hdl.handle.net/10962/d1010638
- Description: Underwater observations of the coelacanth, Latimeria chalumnae Smith, 1939, from a research submersible provided opportunities to study the deep demersal fish fauna at the Comoro Islands. The demersal habitat in depths of 150–400 m at the volcanic island of Ngazidja is low in fish diversity and biomass, compared with the shallow-water coral reef habitat of Ngazidja or the deep demersal habitats of other localities in the Indo-Pacific region. The resident deep demersal fish fauna at Ngazidja is dominated by the coelacanth, an ancient predator that is specially adapted for this low-energy environment. Other large fish predators are scarce in this environment, because of the heavy fishing pressure from local fishermen. Eighty-nine fish taxa (including 65 recognizable species) were recorded from videotapes, photographs, visual observations, fishermen’s catches and ancillary attempts to sample the fish fauna with baited fish traps, gill nets, and hook and line. Although no coelacanth feeding events were seen, seven fish species are known from coelacanth stomach contents, and 64 other fish species in this habitat are considered potential prey of this dominant predator.
- Full Text:
- Date Issued: 2006