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Trophodynamics of mesozooplankton in the the vicinity of the subtropical convergence in the Indian sector of the Southern Ocean

  • Authors: Daly, Ryan
  • Date: 2009
  • Subjects: Zooplankton -- Antarctic Ocean , Phytoplankton -- Antarctic Ocean
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5791 , http://hdl.handle.net/10962/d1005479 , Zooplankton -- Antarctic Ocean , Phytoplankton -- Antarctic Ocean
  • Description: The trophodynamics of the numerically dominant mesozooplankton (200-2000 m) in the vicinity of the Subtropical Convergence (STC) in the Indian sector of the Southern Ocean during austral autumn (April / May) 2007 were investigated as part of the Southern Ocean Ecosystem Variability Study. The survey consisted of six north-south transects each bisecting the STC between 38º to 43ºS and 38º to 41º45’E. In total, 48 stations situated at 30 nautical mile intervals were occupied over a period of ten days. Hydrographic data revealed a well defined surface and sub-surface expression of the STC, which appeared to meander considerably between 41ºS and 41º15’S. Surface chlorophyll-a (chla) concentrations were low, ranging between 0.08 and 0.68 mg chl-a.m-3 and were generally dominated by the picophytoplankton (<2 m) which made up 66.6% (SD±17.6) of the total pigment. Chl-a concentrations integrated over the top 150m of the water column ranged between 11.97 and 40.07 mg chl-a.m-2 and showed no significant spatial patterns (p>0.05). Total integrated mesozooplankton abundance and biomass during the study ranged between 3934.9 and 308521.4 ind.m-2 (mean = 47198.19; SD±62411.4 ind.m-2) and between 239.8 and 4614.3 mg Dwt.m-2 (mean = 1338.58; SD ±1060.5), respectively. Again, there were no significant spatial patterns in the total mesozooplankton abundance or biomass within the region of study (p>0.05). No significant correlations were found between biological (chlorophyll-a concentrations and zooplankton abundance) and physico-chemical variables (temperature and salinity) (p>0.05). The total mesozooplankton community was numerically dominated by copepods of the genera Pleuromamma, Calanus, Oncaea and Oithona. Other important representatives of the mesozooplankton community included the tunicate, Salpa thompsoni, and the pteropod, Limacina retroversa. At the 40% similarity level, numerical analysis identified five distinct mesozooplankton groupings within the survey area. Differences between the groupings were associated with changes in the relative contribution of numerically dominant species rather than the presence or absence of individual species. No groupings were associated with any specific feature of the front within the survey area. The feeding rates of the six most numerically abundant mesozooplankton species (Calanus simillimus, Limacina retroversa, Pleuromamma abdominalis, Clausocalanus breviceps, Oncaea conifera, Salpa thompsoni) accounting for on average 39% of the total mesozooplankton counts, were investigated using the gut fluorescence technique. For all species, the total gut pigment contents during the night time were significantly higher than the daytime values (p<0.05 for all species). The gut evacuation rates (k) for selected mesozooplankton ranged between 0.14 and 0.81 h-1. The ingestion rates ranged between 147.8 and 5495.4 ng(pigm)ind-1.day-1 which corresponded to a daily ration of between 2.4 and 10.9% body carbon. The combined grazing impact of the selected species on the daily phytoplankton standing stock was highly variable and ranged between 1.2 and 174.1% with an average of 27.3% (SD±38.78%) within the survey area. The highest grazing impact (>60%) was typically associated with those stations where the pteropod, L. retroversa, and the tunicate, S. thompsoni, contributed more than 5% of the total mesozooplankton counts. No significant differences were found in the grazing impact of any or all selected species situated either north, south or in the immediate vicinity of the front (p>0.05 in all cases). The lack of defined spatial patterns in the mesozooplankton abundance and community structure suggests that the STC did not act as a significant biogeographic barrier to the distribution of mesozooplankton during the study. It is presumed that the large scale mixing event caused by a storm prior to this study was responsible for the observed lack of elevated biological activity within the region of the STC.
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  • Date Issued: 2009

Understanding form and technique : Andrew Tracey's contribution to knowledge of lamellophone (mbira) music of Southern Africa

  • Authors: Gumboreshumba, Laina
  • Date: 2009
  • Subjects: Tracey, Andrew T N Ethnomusicology -- Africa Mbira Mbira music
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2638 , http://hdl.handle.net/10962/d1002303
  • Description: This thesis interrogates Andrew Tracey’s career as an ethnomusicologist and the significance of his research and publications on lamellophone (mbira) music of the Shona/Sena in Zimbabwe and Mozambique to subsequent scholarship of lamellophones throughout southern Africa. Through a survey of authors who have cited Tracey’s publications, this study assess how his use of the pulse notation transcription method and his theory of form and harmonic structure in mbira music, which he terms ‘the system of the mbira’ (A. Tracey, 1989) have influenced and contributed to the work of ethnomusicologists, musicologists and composers. Further this research evaluates the impact on subsequent publications by other scholars of Tracey's technical analysis of mbira music. Organizing and indexing Andrew Tracey's field collection in the ILAM archive gave direct knowledge of the scope of his work. The thesis consists of six chapters. The first chapter contains a general introduction to the thesis and outlines the goals of the research. Chapter Two presents a biographical sketch of Andrew Tracey. A general introduction to the lamellophone (mbira) family of musical instruments in Zimbabwe and elsewhere in Africa is presented in Chapter Three, which also addresses the social function of lamellophone music. Chapter Four gives a summary of Andrew Tracey’s research on the Shona mbira (his publications, recordings, films etc), and it analyzes his theory - “The system of the mbira” - in which he defines the form and structure of mbira music. Chapter Five examines the impact of Andrew Tracey’s research and publications on mbira music to subsequent scholarship and makes an analysis and evaluation of the significance of his contribution to the body of knowledge of the instrument and its music. In addition I relate my personal experiences with mbira music as a Shona person and mbira player and give my opinions on Tracey’s and subsequent scholars’ theories on mbira music. Chapter Six concludes with a summary of outcomes of this research. Basing on the analyses of presented data, it is deduced that, despite a few shortcomings, Andrew Tracey’s research on mbira music is crucial for it laid the groundwork for subsequent mbira scholarship.
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  • Date Issued: 2009

Understanding propaganda: Noam Chomsky and the institutional analysis of power

  • Authors: Cathey, Paul Eben
  • Date: 2009
  • Subjects: Chomsky, Noam -- Political and social views Propaganda Gramsci, Antonio, 1891-1937 -- Political and social views Social classes
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2765 , http://hdl.handle.net/10962/d1002975
  • Description: This thesis argues that Noam Chomsky’s theory of propaganda is a useful way to understand class domination. The strengths and weaknesses of Chomsky’s theory are examined by means of a comparison with Antonio Gramsci’s theory of cultural hegemony. Since work that discusses and analyses Chomsky’s theory is sparse, this piece first gives a detailed explanation of his theory. This requires a short clarification of Chomsky’s terminology, focusing on his definitions of indoctrination and class. Thereafter a thorough account of Chomsky’s ideas regarding class structure, the indoctrinating functions of educational and media institutions and the difference between upper and lower class propaganda are discussed. A common criticism of Chomsky’s arguments is that they are conspiratorial. Thus, following the discussion of Chomsky’s theory I present an argument that Chomsky uses an institutional analysis as opposed to conspiracy theory to reach his conclusions. After arguing that Chomsky has a coherent, logical theory of propaganda that is not conspiratorial, this thesis shifts to a comparison of Chomsky and Gramsci’s theory. The elements of Gramsci’s theory that are relevant to Chomsky are discussed, focusing on their overall similarities, in particular, the question of consent. The final chapter consists of a comparison of the two theories, examining each theorist’s ideas on the nature of education, language, consent and the possible ways in which the lower classes can oppose their own oppression.
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  • Date Issued: 2009

Understanding the complexity of metabolic regulatory systems an investigation into the regulation of hydantoin-hydrolysis in Pseudomonas putida RU-KM3s

  • Authors: De la Mare, Jo-Anne
  • Date: 2009
  • Subjects: Pseudomonas , Hydantoin , Hydrolysis , Enzymes -- Regulation
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:3993 , http://hdl.handle.net/10962/d1004053 , Pseudomonas , Hydantoin , Hydrolysis , Enzymes -- Regulation
  • Description: It has been well-established that Pseudomonas species possess extremely versatile metabolic systems allowing them to utilise a wide range of nutrient sources and, furthermore, that the regulation of these enzyme systems involves highly evolved and sophisticated regulatory machinery. This study examined the complexity of metabolic regulation in Pseudomonas using the hydantoin-hydrolysing system of the environmental isolate, Pseudomonas putida RU-KM3s. In this system, the genes encoding dihydropyrimidinase and β-ureidopropionase (dhp and bup) are arranged divergently on the chromosome, separated by a 616 bp intergenic region involved in the transcriptional regulation of these genes. The focus was on the transcriptional regulation of dhp expression. DHP activity was found to be sensitive to several environmental signals including growth phase, carbon catabolite repression (CCR), substrate induction and quorum sensing (QS). Bioinformatic analysis of the intergenic region upstream of dhp revealed a number of putative binding sites for transcriptional regulators, including recognition sequences for the alternate sigma factors σ54 and σ38, as well as for the global regulators Anr (for anaerobic regulator) and Vfr (for virulence factor regulator). The targeted disruption of the genes encoding the transcriptional regulators, Vfr and the major CCR protein, Crc, resulted in a partial relief from repression for the vfr- mutant under quorum sensing conditions and a general decrease in activity in the crc- mutant. This data suggested that both Vfr and Crc were involved in regulating DHP activity. Mutational analysis of the dhp promoter revealed that at least two sites were involved in regulating transcriptional activity, one which mediated activation and the other repression. These sites were designated as a putative Anr box, situated 232 bp from the start codon of dhp, and a CRP-like binding site, at a position 213 bp upstream of dhp. Taken together, this data shows the involvement of several global regulatory factors in controlling the expression of dhp. A complex synergistic model was proposed for the transcriptional regulation of dhp, involving alternate sigma factors in addition to both global and specific regulators and responding to a number of environmental signals associated with growth phase, including nutrient availability, cell density and oxygen status.
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  • Date Issued: 2009

Understanding the differences in marking performance of JSC mathematics markers in Namibia : a case study

  • Authors: Mutuku, Elizabeth
  • Date: 2009
  • Subjects: Educational change -- Namibia , Mathematics -- Namibia -- Examinations -- Case studies , Mathematics -- Study and teaching -- Namibia -- Case studies , Grading and marking (Students) -- Namibia -- Case studies
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1999 , http://hdl.handle.net/10962/d1015223
  • Description: Education reform in Namibia brought about changes to mathematics education since independence. This has put pressure on the government to provide both resources and qualified mathematics teachers to help drive the reform process in all teaching and learning activities. This included availing reliable and valid national examination results which is a measure of whether the newly introduced programmes are working or not. For the Ministry of Education this meant training more mathematics teachers and ensuring that competent and reliable teachers are appointed for marking national examination every year. The teachers' training process however, has not been going as fast as it was expected and year after year the Directorate of National Examinations and Assessment experienced problems in obtaining competent teachers for the marking of national examination. The purpose of the study was to understand the differences in marking performances of the JSC mathematics national examination markers. Particularly the study was to create a clear and detailed understanding of different factors that could possibly affect the marking performance of different markers. In addition, the study was to investigate the effect the mathematical content knowledge of the markers has on their marking performance. It was evident from the findings that their mathematical content knowledge had influenced their marking performance. Moreover the research findings also gave a strong indication that there are other factors that were influencing the markers marking performance. These were the markers' knowledge of the assessment and marking process, the markers' marking experience, the markers' socioeconomic background. The difference in their moderators' input has emerged as the other factors that have influenced their performance in marking and consequently contributed to the differences in their marking performances.
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  • Date Issued: 2009

Unearthed : personifications of widowhood and acts of memory : volume 1 and 2

Urban community development: an understanding of social change and identity in a social housing estate in post-apartheid South Africa

  • Authors: Packery, Rajendra
  • Date: 2009
  • Subjects: Communities , Social change , Community development -- South Africa
  • Language: English
  • Type: Thesis , Masters , M Soc Sc
  • Identifier: vital:11967 , http://hdl.handle.net/10353/241 , http://hdl.handle.net/10353/d1001312 , Communities , Social change , Community development -- South Africa
  • Description: This study focuses on the lives of people living in a social housing estate which was a joint venture between the Housing Association of South Africa (HASA), a Netherlands based foundation and the Buffalo City Municipality. This type of social housing estate is a relatively new concept in post-apartheid South Africa and a first for the City of East London. Apartheid spawned the separation of different groups of people into racial enclaves. It also created barriers between races, advantaged certain races over others and created fear, hatred and general distrust among different racial groups in South Africa. The dislocation of apartheid was accompanied by rapid urbanization and ‘reconstruction’ of infrastructure and inter-racial relationships. The opening up of the country’s borders in compliance with Globalisation made South Africa a melting pot to people of different cultures. South African cities became fragmented and fear and strangeness was everywhere. Housing or the lack of it has been a constant problem that the new post apartheid government has grappled with. The solution of building RDP housing estates has not solved this burgeoning problem. But even more importantly it has failed to reorganize urban life in South Africa. In approaching this study I look at how these new social housing estates have reorganized urban life. I explore the concepts of community, home, generation, gender, material culture and ‘new’ urbanization to provide a framework for my study. This study is a qualitative study based in the city of East London in the Eastern Cape. It is a community study which attempts to go inside the home to unlock some of the intricacies of urban life. Ethnography is the research key used to unlock these intricacies.In conclusion, this study attempts to examine a non-western narrative of community life. Are these housing estates a solution to South Africa’s housing problem? Do they conform only to western narratives of urban life? What kind of citizens do these housing estates produce? These are some of the questions that this study hopes to answer.
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  • Date Issued: 2009

Usefulness of the neo PI-R personality profiles in the selection of psychology master's applicants

  • Authors: Hurter, Kim
  • Date: 2009
  • Subjects: NEO Personality Inventory , Dregrees, Academic -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9907 , http://hdl.handle.net/10948/d1009640 , NEO Personality Inventory , Dregrees, Academic -- South Africa
  • Description: Each year, psychology departments across South Africa are faced with the arduous task of selecting the most suitable candidates to fill their Clinical, Counselling, Educational, and Industrial Psychology master’s coursework programmes. Although various criteria are considered in this process, personality has long been considered an important variable in the screening and selection of master’s psychology applicants, and some sort of personality assessment is commonly utilized by selection committees as part of the screening and selection procedures. While there are many different theoretical perspectives on personality and various personality assessment measures available, the Five-Factor Model (FFM) of personality has gained considerable attention over the last decade as a comprehensive and universal conceptualization of a broad trait structure for human personality. Currently, the Revised NEO Personality Inventory (NEO PI-R) is considered to be one of the best commercially available measures of the personality traits proposed by this model. The NEO PI-R provides a comprehensive measure of adult personality, has been extensively researched, and has demonstrated its utility across many different cultures, languages, and contexts. The aim of this study was to explore and describe the personality profiles of short-listed master’s psychology applicants at a higher education institution in South Africa, using the NEO PI-R, in an effort to explore the use of NEO PI-R profiles in the selection of master’s psychology applicants. The study was exploratory descriptive in nature and employed a quantitative research method. The sample of 247 participants was selected according to non-probability convenience sampling and was sourced from an archival research database. As part of the application process at the higher education institution, applicants were required to complete various tests, tasks, and questionnaires. The questionnaires selected for this study included a biographical questionnaire, used to describe the biographical variables of the sample, and the NEO PI-R (Costa & McCrae, 1992), used as a measure of personality. The NEO PI-R has been found to have good validity and reliability, with reliability in particular having being established in the South African context. Descriptive and inferential statistics, including correlations, cluster xiv analysis, and multivariate analysis of variance (ANOVA), were utilized to analyze the data. Key findings revealed that overall, the group of short-listed master’s psychology applicants could be described as being emotionally well-adjusted and sociable, which is in line with previous national and international research. In addition, a cluster analysis revealed three significantly different personality subgroups within the total sample, thus highlighting the heterogeneous nature of this sample of applicants. Each of the three personality subgroups exhibited significantly different personality traits which were judged to be more or less suitable for potential psychologists-in-training. Clusters 1 and 2 exhibited the most desirable personality characteristics in relation to selection into a master’s psychology programme, while Cluster 3 exhibited the least desirable traits. Various classification functions were derived which classified applicants into “selected” and “not selected” groups as well as the three personality subgroups, which could aid selection committees in the future to screen out potentially unsuitable candidates earlier in the selection process. It was concluded that the use of NEO PI-R personality profiles could aid the screening and selection of short-listed master’s psychology applicants.
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  • Date Issued: 2009

Using semantic knowledge to improve compression on log files

  • Authors: Otten, Frederick John
  • Date: 2009 , 2008-11-19
  • Subjects: Computer networks , Data compression (Computer science) , Semantics--Data processing
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4650 , http://hdl.handle.net/10962/d1006619 , Computer networks , Data compression (Computer science) , Semantics--Data processing
  • Description: With the move towards global and multi-national companies, information technology infrastructure requirements are increasing. As the size of these computer networks increases, it becomes more and more difficult to monitor, control, and secure them. Networks consist of a number of diverse devices, sensors, and gateways which are often spread over large geographical areas. Each of these devices produce log files which need to be analysed and monitored to provide network security and satisfy regulations. Data compression programs such as gzip and bzip2 are commonly used to reduce the quantity of data for archival purposes after the log files have been rotated. However, there are many other compression programs which exist - each with their own advantages and disadvantages. These programs each use a different amount of memory and take different compression and decompression times to achieve different compression ratios. System log files also contain redundancy which is not necessarily exploited by standard compression programs. Log messages usually use a similar format with a defined syntax. In the log files, all the ASCII characters are not used and the messages contain certain "phrases" which often repeated. This thesis investigates the use of compression as a means of data reduction and how the use of semantic knowledge can improve data compression (also applying results to different scenarios that can occur in a distributed computing environment). It presents the results of a series of tests performed on different log files. It also examines the semantic knowledge which exists in maillog files and how it can be exploited to improve the compression results. The results from a series of text preprocessors which exploit this knowledge are presented and evaluated. These preprocessors include: one which replaces the timestamps and IP addresses with their binary equivalents and one which replaces words from a dictionary with unused ASCII characters. In this thesis, data compression is shown to be an effective method of data reduction producing up to 98 percent reduction in filesize on a corpus of log files. The use of preprocessors which exploit semantic knowledge results in up to 56 percent improvement in overall compression time and up to 32 percent reduction in compressed size. , TeX , pdfTeX-1.40.3
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  • Date Issued: 2009

Using the van Hiele theory to analyse geometrical conceptualisation in grade 12 students: a Namibian perspective

  • Authors: Mateya, Muhongo
  • Date: 2009
  • Subjects: Hiele, Pierre M. van Hiele-Geldof, Dina van Geometry -- Study and teaching (Secondary) -- Namibia Mathematics -- Study and teaching (Secondary) -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1820 , http://hdl.handle.net/10962/d1003706
  • Description: The study reported here utilised a theory of levels of geometric thinking. This theory was proposed and developed by two Dutch mathematics educators, Pierre van Hiele and his wife, Dina van Hiele-Geldof. The van Hiele theory enables investigations into why many students experience difficulties in learning geometry. In many nations, such as the UK, the USA, Netherlands, the USSR and to a certain extent, Nigeria and South Africa, research evidence has indicated that the overall students’ mathematical competencies are linked to their geometric thinking levels. This study is the first of its kind to apply the van Hiele theory of geometric thinking in the Namibian context to analyse geometrical conceptualisation in Grade 12 mathematics students. In all, 50 Grade 12 students (20 from School A and 30 from School B) were involved in this study. These students wrote a van Hiele Geometry Test adapted from the Cognitive Development and Achievement in Secondary School Geometry test items. Thereafter, a clinical interview with the aid of manipulatives was conducted. The results from this study indicated that many of the School A and School B students who participated in the research have a weak conceptual understanding of geometric concepts: 35% of the School A and 40% of the School B subsamples were at the prerecognition level. 25% and 30% of the School A, and 20% and 23.3% of the School B students were at van Hiele levels 1 and 2 respectively. An equal number of students but different in percentages, 2 (10%) in School A and 2 (6.7%) in School B, were at van Hiele level 3. Only one student from School B attained van Hiele level 4. These results were found to be consistent with those of previous similar studies in UK, USA, Nigeria and South Africa. The findings of this study also highlight issues of how the Namibian Grade 12 geometry syllabus should be aligned with the van Hiele levels of geometric thinking as well as the use of appropriate and correct language in geometrical thinking and problem solving.
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  • Date Issued: 2009

Valuing preferences for freshwater inflows into five Eastern Cape and Kwazulu-Natal estuaries

  • Authors: Chege, Jedidah
  • Date: 2009
  • Subjects: Estuarine ecology -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Kwazulu-Natal , Freshwater ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Estuaries -- Management -- South Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:8990 , http://hdl.handle.net/10948/932 , Estuarine ecology -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Kwazulu-Natal , Freshwater ecology -- South Africa -- Eastern Cape , Estuaries -- South Africa -- Eastern Cape , Estuaries -- Management -- South Africa
  • Description: An estuary, according to the National Water Act of 1998, is a partially or fully enclosed body of water which is open periodically or permanently to the sea within which the sea water can be diluted, to an extent that is measurable with freshwater from inland. Estuaries and the lands surrounding them are places of transition from land to sea, and from freshwater to saltwater. Although influenced by the tides, estuaries are protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers of land, mud, or sand that surround them. South Africa’s estuaries are important and irreplaceable habitats, especially for prawns, fish, wading birds and mangroves. They are home to numerous plants and animals that live in water that is partly fresh and partly salty. Estuaries are also homes to growing coastal communities as increasing number of people occupy watersheds. However, estuaries are also threatened. One of the threats is reduced river water inflow. This study applies the contingent valuation method (CVM) to elicit user’s willingness to pay to mitigate the negative impacts of reduced freshwater inflow into selected five Eastern Cape and Kwazulu-Natal estuaries: the Sundays, Gamtoos, Mdloti, Mgeni and Mvoti estuaries. In addition to the contingent valuation method, the travel cost method was used to generate comparative values. The contingent valuation method is a technique to establish the value of a good (or service) that is not bought or sold in an actual market. The CVM establishes the economic value of the good by asking the users of an environmental good to state their willingness to pay (WTP) for a hypothetical project to prevent, or bring about, a change in the current condition of the environmental good. The users’ WTP is aggregated to establish a total willingness to pay (TWTP) for the population of the users of the environmental good.
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  • Date Issued: 2009

Valuing preferences for freshwater inflows into selected Western and Southern Cape estuaries

  • Authors: Akoto, William
  • Date: 2009
  • Subjects: Estuarine ecology -- South Africa , Freshwater ecology -- South Africa , Estuaries -- South Africa
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:8992 , http://hdl.handle.net/10948/915 , Estuarine ecology -- South Africa , Freshwater ecology -- South Africa , Estuaries -- South Africa
  • Description: An estuary is the last stage of a river. It is where the river meets the sea. Estuaries are one of the most significant features of the South African coastline. In recent years, South Africa has witnessed an increase in the demand for freshwater for both industrial and domestic purposes. At the same time, there has been a gradual deterioration of river systems and their catchments. To add to this, there has been a gradual reduction in the amount of recorded rainfall, which is the primary source of freshwater for rivers. This has resulted in decreased freshwater inflow into estuaries, a situation which poses a serious threat to the biological functioning of these estuaries and the services rendered to its recreational users. A deterioration of estuary services reduces the yield for subsistence households and their appeal for recration. This study uses the contingent valuation method as its primary methodology to elicit users' willingness-to-pay to reduce the negative impacts of reduced freshwater inflow into selected western and southern Cape estuaries. Eight estuaries were selected for this study; the Breede, Duiwenhoks, Great Berg, Kleinemond West, Mhlathuze, Swartvlei and Olifants estuaries. The contingent valuation (CV) method is widely used for studies of this nature because of its ability to capture active, passive and non-use values. The CV method involves directly asking people how much they would be willing to pay for specific environmental services. In this case, users were asked what they would be willing to pay to sustain freshwater inflows into selected estuaries in order to prevent the negative impacts of reduced inflows. The travel cost method (TCM) was uesed to generate an alternative comparative set of values for the purposes of convergence testing. This is because convergence testing is highly desirable as a validity test for CV estimates.
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  • Date Issued: 2009

Variability analysis of a sample of potential southern calibration sources

Vincent van Gogh : a psychobiographical study

  • Authors: Muller, Heather Ruby
  • Date: 2009
  • Subjects: Psychology -- Biographical methods
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:9880 , http://hdl.handle.net/10948/1293 , Psychology -- Biographical methods
  • Description: The aim of this study is to create a psychobiography of Vincent Van Gogh who was born in 1853 and died 1890. To Van Gogh art was not merely a means for an income, he converted all his aspirations and anguish into his art works. In doing so his art became the first example of a truly personal art, to him art was a deeply lived means of spiritual salvation, which he used as a means to transform himself. It was well known that Van Gogh was unstable and felt misunderstood in life, often asking “What is the use?” . He had a method of fusing what he saw in the world, and what he personally felt, into works of art that were revelations of himself. Van Gogh lived a lonely life, although for the last seventeen years of his life he wrote to his brother, Theo, almost daily. These letters give much insight to the thoughts and inner world of a much misunderstood individual. Most of these letters have been preserved and much else has been written about Van Gogh’s life and art. In our modern day he is deemed one of the most famous artists, yet in his lifetime he only sold one painting. This psychobiography employs a qualitative psychobiographical research method, which aims to describe Van Gogh’s psychological development in terms of Erik Erikson’s psychosocial developmental stages. Van Gogh was chosen as the research subject because of personal interest, his value as a famous artist, and because of the unique way in which he saw and related to the world.
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  • Date Issued: 2009

Vocational language learning and how it relates to language policy issues

Warthog as an introduced species in the Eastern Cape

  • Authors: Nyafu, Kanyisa
  • Date: 2009
  • Subjects: Warthog -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10701 , http://hdl.handle.net/10948/1058 , Warthog -- South Africa -- Eastern Cape
  • Description: The introduced common warthog, Phacochoerus africanus, in the Eastern Cape is increasing rapidly both in numbers and distribution, despite attempts by landowners to reduce numbers and exclude warthogs. These control attempts are motivated by concerns over the impacts of warthogs, on vegetation, soil and other animal species. This expansion of warthog populations is paradoxical given that a species of warthog occurred historically in this part of the world, apparently at low densities and was wiped out in the mid-1800s. The question therefore arises as to why warthogs are able to overcome population regulation attempts now, and this becomes an invasive species issue as the species now occurring in the Eastern Cape is in fact an introduced species. The objectives of the study were to investigate the status of warthogs as an introduced invasive species in the Eastern Cape by documenting the rate and direction of population expansion, ecological impacts and possible dietary shift of the introduced species, P. africanus compared to the extinct species P. aethiopicus. The research approach adapted here was to test the hypotheses that, (1) the success of P. africanus in the Eastern Cape reflects dietary differences of the two species based on observations of different dental adaptations, as P. africanus has functional incisors, which are absent in P. aethiopicus. Stable carbon isotope analysis of the tooth enamel was used to determine the diet of the two species. (2) Common warthogs are specialized grazers and will impact on a limited range of grass species, this hypothesis was addressed by describing the diet of common warthogs in one site in the Eastern Cape to identify plant species at risk due to invasion by P. africanus, and microhistological faecal analysis was used. (3) Common warthogs have successfully expanded their range in the Eastern Cape since their introduction and are now showing impact, this was addressed by describing the range of expansion of P. africanus in the Eastern Cape, as well as reviewing landowner perceptions of the impacts of warthogs, this was based on questionnaire surveys distributed in the Sundays and the Fish River valleys. The results of the study showed that there are differences in the diet of Cape warthog P. aethiopicus and common warthog P. africanus. The Cape warthog was largely a grazer (86 percent C4 grasses in their diet), while P. africanus is also a grazer (71 percent of C4 grasses in their diet), but with a larger proportion of browse in their diet. These results support the hypothesis that the presence of functional incisors in the common warthog might provide the common warthog with foraging advantages over the Cape warthog. This might be a contributing factor to the success of this invasive species in the Eastern Cape, and might explain the rapid disappearance of Cape warthogs in the 1800s, which coincided with rapid expansion of herds of domestic grazers. A total of twelve grass species are used by common warthogs and are therefore most vulnerable to impacts of this invasive species. Common warthogs are rapidly expanding their range particularly around the Sundays and the Great Fish River valleys and they are perceived by landowners to have impacts on grass cover, soils and fencing. This spread of warthog in the Eastern Cape exhibits characteristics of an invasive species. In light of the findings of this study, it is therefore important that government authorities and other parties concerned recognize that common warthogs are invasive in the Eastern Cape.
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  • Date Issued: 2009

Workers' perceptions of occupational safety and health administration measures at Sasol Infrachem in Sasolburg

  • Authors: Kwayiba, Thamsanqa Felix
  • Date: 2009
  • Subjects: Petroleum chemicals industry -- Sasolburg , Industrial hygiene -- South Africa -- Sasolburg , Industrial safety -- South Africa -- Sasolburg
  • Language: English
  • Type: Thesis , Masters , MPhil (Environmental Studies)
  • Identifier: vital:11878 , http://hdl.handle.net/10353/d1001090 , Petroleum chemicals industry -- Sasolburg , Industrial hygiene -- South Africa -- Sasolburg , Industrial safety -- South Africa -- Sasolburg
  • Description: This is a qualitative study that seeks to explore the workers’ perceptions towards the occupational safety and health administration (OSHA) system at the petrochemical industrial plant Sasol Infrachem in Sasolburg. It provides a platform for shop floor workers to express their subjective perceptions of the company’s OSHA measures by answering open ended questions. The study advances the notion that notwithstanding the safety managers’ efforts towards ensuring a safety regime in the workplace, however lucrative these might be, to really ensure a safe working environment in the workplace will always depend on the individual workers’ motivation to participate safely at work at any given time to ensure his/her safety and that of others. The study explores this subject by considering how they perceive these safety strategies, their vigilance, attitudes, their ownership of these and their inclination to comply with the occupational safety and health administration measures of Sasol. This study follows a Postmodernist theoretical framework emphasizing differences. Difference is a first and foremost identity feature of human beings. This goes for both their external and internal qualities. How workers perceive and relate to safety concepts will always be shaped by the differences among them. The study also makes use of the Environmental Justice Theory as a central theme, that holds that one life lost is one too many. At the forefront of industries are shop floor workers who are most vulnerable to workplace incident.The study assumes this premise with regard to their safety and health in the workplace
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  • Date Issued: 2009
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