List of Titles

Water quality, abalone growth and the potential for integrated mariculture on a South African abalone Haliotis midae L. farm

- Yearsley, Rowan David

Authors: Yearsley, Rowan David
Date: 2008
Subjects: Abalones -- South Africa Abalone culture -- South Africa Abalones -- Growth Mariculture -- South Africa Water quality -- South Africa
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5334 , http://hdl.handle.net/10962/d1005180
Description: Abalone Haliotis midae farming in South Africa is highly intensive, employing pump-ashore, flow-through systems. Despite the known sensitivity of abalone to water quality, there is only a rudimentary understanding of water quality dynamics on South African abalone farms and its effects on abalone production. Furthermore, the potential for reusing the relatively dilute abalone farm effluent to culture other animal species has not been investigated. This study investigated the dynamics of water quality and growth on a South African abalone farm and assessed the suitability of the effluent for the culture of silver kob Argyrosomus inodorus and bloodworm Arenicola loveni loveni. Monitoring of water quality and abalone growth in abalone tanks revealed that oxygen concentrations decreased, while H⁺ ion and free-ammonia (NH₃) concentration increased in a gradient between the inflow and outflow. Abalone growth was positively correlated with oxygen concentration and negatively correlated with free-ammonia and H⁺ ion concentration. The oxygen (O) concentration of the farm influent was dependent upon the influents’ temperature (T) and was described by the relationship O (mg L⁻¹) = 11.244 – 0.208T (r²=0.74). Linear regression analysis of data collected from abalone farm tanks revealed that the concentration of total ammonia at the outflow of abalone tanks (μg TAN L⁻¹) was dependant upon temperature (°C), flow-rate (L s⁻¹ kg⁻¹ H. midae), abalone size (g) and length of time since the tank was last cleaned (d) (n = 125, r² = 0.80). The production of total ammonia (μg TAN s⁻¹ kg⁻¹) was related to temperature, abalone size and days that the tanks remained un-cleaned (n = 125; r² = 0.81). A diurnal cycle of respiration was evident in abalone tanks with higher oxygen consumption and H+ ion production at night. The oxygen concentration of farm effluent was related to temperature, farm biomass and flow rate by means of a linear regression equation (n = 40; r² = 0.69). The results demonstrated the importance of optimising the flow-rate per unit of biomass for various temperatures and sizes of abalone. As abalone size and temperature cannot be controlled under farm conditions, the flow-rate per unit of biomass which the abalone culture system receives will determine the quality of the culture water. The specific growth rate (0.48 ± 0.01 % BW d⁻¹), mortality (1.8 ± 0.5 %), feed conversion ratio (3.0 ± 0.2) and protein efficiency ratio (1.0 ± 0.1) of silver kob kept in either abalone farm effluent or control seawater for 120 days did not differ significantly (t-test, P>0.05). A 90 day growth trial indicated that abalone farm effluent is a suitable culture medium for bloodworm. Bloodworm supplied with control seawater lost weight at 0.19 ± 0.04 % BW d-1, while those given abalone effluent grew at 0.39 ± 0.07 % BW d⁻¹. Mortality was 6 ± 3 % in effluent and 11 ± 8 % in seawater. The bloodworm were efficient at processing solid waste. Abalone farm effluent initially contained 7.7 ± 13 mg L⁻¹ more suspended solids than control seawater, which contained 3.5 ± 0.5 mg L⁻¹, but after passing through bloodworm systems the concentration in abalone effluent was reduced to only 1.4 ± 3.5 mg L⁻¹ above that in control seawater. Therefore, abalone farm effluent could be reused as a culture medium for both silver kob and bloodworm. Future work is needed to investigate aspects of the feasibility of such systems such as growth rates at different sizes and stocking densities.
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WET-Origins: controls on the distribution and dynamics of wetlands in South Africa

- Ellery, William F N, Grenfell, Michael C, Grenfell, Suzanne E, Kotze, Donovan C, McCarthy, Terence S, Tooth, Stephen, Grundling, Piet-Louis, Beckedahl, Heinz, Le Maitre, David C, Ramsay, Lisa F

Authors: Ellery, William F N , Grenfell, Michael C , Grenfell, Suzanne E , Kotze, Donovan C , McCarthy, Terence S , Tooth, Stephen , Grundling, Piet-Louis , Beckedahl, Heinz , Le Maitre, David C , Ramsay, Lisa F
Date: 2008
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/176598 , vital:40091 , ISBN 978-77005-633-6 , https://www.wrc.org.za/mdocs-posts/wetland-management-series-wet-origins-controls-on-the-distribution-and-dynamics-of-wetlands-in-south-africa/
Description: The need for wetland rehabilitation in South Africa is compelling: loss and degradation of wetlands have been great and national policy and legislation provide clear direction and support for rehabilitation. However, rehabilitating wetlands is often complex because wetlands and their links with people are complex (e.g. through the ways that people use wetlands and the different benefits that people receive from the ecosystem services that wetlands supply).
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What future subordinates will value in their leaders

- Cox, Andrea, Amos, Trevor L, Baxter, Jeremy

Authors: Cox, Andrea , Amos, Trevor L , Baxter, Jeremy
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/270992 , vital:54499 , xlink:href="https://hdl.handle.net/10520/EJC51031"
Description: Leaders should not randomly choose a leadership style. To be effective, leaders need to ensure that their leadership style is congruent with what subordinates value. The focus of this study is on what the future South African graduate workforce will value in a leader. The female and male respondents in this study emphasise similar leadership values, indicating that there is no distinct set of competencies that will be valued separately by males and females. The same was found for respondents of different cultures, namely African, Coloured, Indian, White and other. With respect to both gender and culture, the respondents emphasise a mixture of African and Western leadership values. This supports the idea that to be effective in South Africa, leaders need to understand the prevailing national cultural values before simply applying ''foreign'' leadership models and theories based upon cultural values found in the West. This research finds that irrespective of gender and culture in the South African workplace, to be effective, leaders need to be loyal and inspirational, have vision and integrity and must be open and honest with their subordinates. Leaders should avoid being autocratic, strict, religious, ritualistic and traditional. They should also avoid using consensus and perceived external control.
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Willingness to pay for the control of water hyacinth in an urban environment of South Africa

- Law, Matthew Charles

Authors: Law, Matthew Charles
Date: 2008
Subjects: Water hyacinth -- Control -- South Africa , Urban ecology (Sociology) -- South Africa , Biodiversity -- Economic aspects -- South Africa , Biodiversity conservation -- Economic aspects -- South Africa , Biological invasions -- Economic aspects -- South Africa , Biological invasions -- Environmental aspects -- South Africa
Language: English
Type: Thesis , Masters , MCom
Identifier: vital:996 , http://hdl.handle.net/10962/d1002731 , Water hyacinth -- Control -- South Africa , Urban ecology (Sociology) -- South Africa , Biodiversity -- Economic aspects -- South Africa , Biodiversity conservation -- Economic aspects -- South Africa , Biological invasions -- Economic aspects -- South Africa , Biological invasions -- Environmental aspects -- South Africa
Description: Water hyacinth is recognised as one of the most problematic invasive aquatic plant species in Africa. For this reason considerable funds are spent each year on itscontrol. As a consequence of the amount of money being spent on problems such as the invasion of water hyacinth, and because of the recognition of the ongoing and accelerated efforts that are required in the future, recent research has focused on accurately quantifying the costs and benefits of control of invasive species to aid policy decisions.A comprehensive cost-benefit analysis would be able to identify if the funds are justified and are being spent effectively. This thesis provides an example of a cost-benefit analysis of funds spent on the control of water hyacinth in an urban environment in South Africa. In order to develop a comprehensive assessment of the total economic value of the control of water hyacinth to an urban population, the Nahoon River in East London was selected as the study site to calculate the benefits of control. In addition to valuing the direct services provided by the resources that are traded in the market (in this case water provision), a contingent valuation study was undertaken in Abbottsford and Dorchester Heights (two suburbs in East London banking the Nahoon River). These were done in order to assess any non-use value a sample of 132 households of the population has for the control of water hyacinth, and any use values that are not traded in the market, for example recreational value. When the benefits of control of water hyacinth were compared to the costs of one of the least cost effective methods of control (herbicidal control), the benefits outweighed the costs by a ratio of more than 4:1, and for the most cost effective method of control the ratio was almost 6:1. These results provide a justification for the funds that are devoted to the control of water hyacinth, providing an argument for the continued expenditure for its control, and for further research into more cost effective methods of control, such as biological control.
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WISC-IV performance of South African grade 7 English and Xhosa speaking children with advantaged versus disadvantaged education

- Van Tonder, Phia

Authors: Van Tonder, Phia
Date: 2008
Subjects: Wechsler Intelligence Scale for Children Intelligence tests -- South Africa Educational tests and measurements -- South Africa Psychological tests -- Cross-cultural studies Educational psychology -- South Africa Language and languages -- Ability testing Educational evaluation -- South Africa Education, Elementary -- South Africa
Language: English
Type: Thesis , Masters , MA
Identifier: vital:3098 , http://hdl.handle.net/10962/d1003920
Description: Research reveals that the level as well as the quality of education plays a role in the determination of an individual's intellectual capacity. Substantial differences in quality of education for black and white individuals were experienced in South Africa due to Apartheid. Compared to the traditionally white Private and Model C schools, Township/ DET schools had limited resources, as well as a separate syllabus and examination system, a situation that has not improved substantially since democratisation in 1994. Research on black South African adults with the WAIS-III has confirmed significant influences on IQ in association with exposure to either such advantaged (Private/Model C) schooling, or disadvantaged (Township/DET) schooling. However to date there has been no published research on the use of the Wechsler intelligence tests on a black South African child population similarly stratified for quality of education. Therefore, for the purposes of this study, the latest Wechsler Intelligence Scale for Children (WISC-IV) was administered to a sample of 36 Grade 7 learners between the ages of 12-13 (mean 13.01 years), stratified for quality of education to form three comparative groups. Data analyses revealed significant differences on the WISC-IV Factor Indices and Full Scale IQ with the English speaking Private/Model C school group performing the best, followed by the Xhosa speaking Private/ Model C school group, and the Xhosa speaking Township/ DET school group performing the worst. This continuum of lowering is understood to occur abreast of a continuum of decreased exposure to relatively advantaged education. These normative indications are considered to have vital implications for the use of the WISC-IV in the South African cross-cultural situation where vastly differential educational opportunities continue to exist.
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Written out, writing in : orature in the South African literary canon

- Seddon, Deborah Ann

Authors: Seddon, Deborah Ann
Date: 2008
Language: English
Type: Article
Identifier: vital:2263 , http://hdl.handle.net/10962/d1004695
Description: As described by Duncan Brown, South African orature represents "our truly original contribution to world literature" (Brown, Voicing the Text 1). This paper explores how orature might be successfully 'written into' the South African literary canon whilst promoting recognition of its existence as an oral form. My recent experiences of the difficulties, challenges, and benefits of teaching South African orature within the Rhodes University English department, have alerted me to the urgent need for the creation of a student- and teacher-friendly anthology which would collect, re-voice, and adequately contextualise a selection of the seminal works of South African oral poets from the colonial to the post-apartheid periods. Much of this poetry already exists in print-form but, despite an increasing recognition of oral poetry through a number of endeavours such the Poetry Africa Festival, the Lentswe Poetry Project on SABC 2, the Timbila Poetry Project and others, South African orature remains marginal in the country's literary canon. It is largely absent from the curriculum in the literature departments of its universities. The need to redress this situation is crucial, but the process of setting up and teaching an undergraduate course in South African oral poetry, while possible, is complicated. The works of our most important oral poets are scattered in a variety of books, libraries, and collections. The usual process of drawing up a booklist of set texts is undermined by the stark reality that many of the books are out of print. Fully giving voice to these texts is even harder to achieve - CD and video recordings of performances (if they exist at all) are not easily accessed or disseminated.
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‘Boys will be boys’: traditional Xhosa male circumcision, HIV and sexual socialisation in contemporary South Africa

- Vincent, Louise

Authors: Vincent, Louise
Date: 2008
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/141500 , vital:37980 , DOI: 10.1080/13691050701861447
Description: Ritual male circumcision is among the most secretive and sacred of rites practiced by the Xhosa of South Africa. Recently, the alarming rate of death and injury among initiates has led to the spotlight of media attention and government regulation being focused on traditional circumcision. While many of the physical components of the ritual have been little altered by the centuries, its cultural and social meanings have not remained unchanged. This paper attempts to understand how some of these cultural and social meanings have shifted, particularly with respect to attitudes towards sex and the role that circumcision schools traditionally played in the sexual.
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‘Who? what?’: an uninducted view of towards a new psychology of women from post-Apartheid South Africa

- Macleod, Catriona I

Authors: Macleod, Catriona I
Date: 2008
Language: English
Type: Article
Identifier: vital:6251 , http://hdl.handle.net/10962/d1007869 , http://journals.sagepub.com/doi/abs/10.1177/0959353508092088
Description: From the text: Towards a New Psychology of Women (TPNW) promises a new psychology of “women”. On the cover of the second edition, the Toronto Globe and Mail is cited as acclaiming the book as “nothing short of revolutionary” as it “set out to recognize, re-define and understand the day-to-day experience of women”. But when we take a closer look at these “women” we discover that they are in fact “white”, (for the most part) middle-class women living in heterosexual relationships in a liberal democracy. This kind of exclusionary inclusion, in which the use of the generic term “woman” disguises the normative assumptions made about the race, class, sexual orientation and location of women, replicates the phallocentrism evidenced in the normalising masculinist terms “mankind” or “Man”. By now, of course, these kinds of critiques of “white” Western feminism by African American writers (e.g. Collins, 1999) postcolonial feminists (e.g. Mohanty, 1991), African feminists (e.g. Ogundipe-Leslie, 1994; Mangena, 2003), and queer theorists (e.g. Jackson, 1999) are well known.
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