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Some aspects of the ecology of the Eastern Cape rocky Sandelia Bainsii (Pisces : Anabantidae) in the Tyume River, Eastern Cape, South Africa

- Mayekiso, Monde

  • Authors: Mayekiso, Monde
  • Date: 1986
  • Subjects: Anabantidae , Perciformes , Labyrinth fishes
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5196 , http://hdl.handle.net/10962/d1001972 , Anabantidae , Perciformes , Labyrinth fishes
  • Description: This is an account of some aspects of the ecology of the eastern Cape rocky, Sandelia bainsii Castelnau in the Tyume river in the eastern Cape. Previous unpublished work carried out by the Zoology Department of the University of Fort Hare in the mid-seventies indicated that the species was rare in the Tyume river. Because of its uncertain conservation status, its restricted geographic distribution and the lack of information on its biology, demography, feeding and reproductive biology were studied. The species occurs in the upper, middle and lower reaches of the Tyume river and is common in rocky , shallow habitats in the middle reaches of the system. The most important threats to the survival of S. bainsii appear to be habitat alteration and alien species. The presence of these threats and the small size of the population suggest that the species may be vulnerable to local extinction. As the total range of the species extends to only a few rivers in the eastern Cape, the species might face extinction if these threats are faced throughout its range. A detailed study on the autecology of S. bainsii was therefore carried out in order to provide a basis for rational conservation and management of the remaining populations of the species.The age structure and the growth rate of S. bainsii was determined using checks on scales and otoliths. Males grow faster and reach a larger size than females. The maximum length of S. bainsii is compared to that of other anabantids. The longevity of males is 5 years and that of females 3 years. Food preferences were determined by three different methods and the indices of relative importance of food items calculated for different length groups and seasons. S. bainsii was found to be an euryphagous and opportunistic predator whose diet consists largely of insects. A considerable overlap was found between the diet of S. bainsii and that of the two alien species, Salmo gairdneri and Micropterus salmoides which indicates a possibility of competition for food. Mark and recapture experiments showed that S. bainsii is a "sedentary " species which is unlikely to be seriously affected by man-made barriers to fish migration, such as weirs. The species reaches maturity during its second growing season (males 80 - 89mm and females 60 - 69mm) and the length at maturity is related to the modal length of males and females. A large proportion of the fish are thus mature at any given time. The fish spawn repeatedly during the summer breeding season, October to February resulting in near continuous recruitment. The possible adaptive value of this habit is discussed. An attempt is made to evaluate the life history style of S. bainsii in terms of the theory of r - and K- selection and altricial and precocial life history styles
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  • Date Issued: 1986

Some geochemical constraints upon models for the crystallization of the upper critical zone-main zone interval, northwestern Bushveld complex

- Eales, Hugh V, Marsh, Julian S, Mitchell, Andrew A, de Klerk, William J, Kruger, Floris J, Field, Matthew

  • Authors: Eales, Hugh V , Marsh, Julian S , Mitchell, Andrew A , de Klerk, William J , Kruger, Floris J , Field, Matthew
  • Date: 1986
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/136044 , vital:37331 , https://doi.org/10.1180/minmag.1986.050.358.03
  • Description: Ratios between elements Mg, Fe, Co, Cr, Ni, V, and Sc are consistently different in mafic rocks of the upper critical zone, and those above the Bastard unit. Within the 300 m section above the Merensky Reef, 87Sr/86Sr ratios increase from c.0.7063 to c.0.7087, irrespective of rock type. Decoupling of Mg/(Mg + Fe2+) ratios and the Ca contents of plagioclase, and wide variations in the proportions of anorthosite within the Bastard, Merensky, and Merensky Footwall units, are inconsistent with anorthosite formation by simple fractional crystallization of magma batches of limited volume.
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  • Date Issued: 1986

Somlandela uYesu

- Zion Apostolic Holy Church Congregation, Composer not specified, Dargie, Dave

Speach

- Speaker not specified, Dargie, Dave

Speaker on behalf of St Bede's students

- Speaker not specified, Dargie, Dave

Speaker on behalh of old students

- Makhubu, Victor, Reverand, Dargie, Dave

Statement on the State of Emergency

- Henderson, Derek Scott

  • Authors: Henderson, Derek Scott
  • Date: 1986
  • Language: English
  • Type: Text
  • Identifier: vital:7552 , http://hdl.handle.net/10962/d1018429
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  • Date Issued: 1986

Studies in carangid fishes no. 4: the identity of Scomber Sansun Forsskal, 1775

- Smith, J.L.B. (James Leonard Brierley), 1897-1968

Taiwana hama yakanaka

- Bernard Mizeki Shrine congregation, Composer not specified, Dargie, Dave, Hodgson, Janet

Techniques in contemporary book illustration

- Huggins, Linda Wreford

  • Authors: Huggins, Linda Wreford
  • Date: 1986
  • Subjects: Illustration of books -- History -- 20th century
  • Language: English
  • Type: Thesis , Masters , MFA
  • Identifier: vital:2462 , http://hdl.handle.net/10962/d1008567
  • Description: Introduction: Although the hackneyed adage "one picture is worth a thousand words" defies proof and begs argument, the basic value of illustration in graphic communications is beyond dispute. Without attempting to put a relative value on illustration as compared with words, we can still be aware of the special effectiveness of images, in accomplishing communication goals. The roots of illustration go hack to prehistoric pictorial art of engraved or painted figures done on stone. The hand print can be interpreted as one of the first attempts at drawing. Prehistoric pictorial art depicted visually what could not be expressed by word or gestures some had religious significance, some the presence of myth, others plainly diadactic, showing daily life, social communication, the magic of the hunt, death, birth, group life and sexual symbolism. Little is known of the vast lapse of time between prehistoric art and the imagery that man devised in the service of developing civilisations at the dawn of history. With steadily increasing demands upon his skills, the artisan's mastery of the tools and materials progressed, so that by the beginning of recorded time he was in possession of the potential elements for printmaking. Yet the importance of communication, as we know it today, only developed centuries later with the motivating force of religion. The print could tell its story to those who could not read or write but could quickly grasp the meaning of a picture.
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  • Date Issued: 1986

Tempera painting: an investigation of the aesthetic and technical advantages of the medium

- De Bliquy, Leon Paul

  • Authors: De Bliquy, Leon Paul
  • Date: 1986
  • Subjects: Painting -- Technique Tempura painting
  • Language: English
  • Type: Thesis , Masters , MFA
  • Identifier: vital:2469 , http://hdl.handle.net/10962/d1009443
  • Description: From Introduction: The balance between practical and theoretic components in the total submission bears relation to the title of this essay where aesthetic advantages are largely theoretical and where technical advantages refer mainly to the practical component. The historical significance of this structure is to be found in the earliest treatises on painting, Cenninni's treatment of painting as a purely practical matter is in accord with medieval tradition. His recipes are aligned according to the various individual techniques, tempera painting being the most significant to this essay. Practical recipes are interspersed with directions for the representation of various pictorial themes, and in the resultant conglomeration, the subdivisions are discernible only as basic premises. In contrast to him, the Renaissance authors beginning with Alberti make a significant innovation in that they divide their material into a theoretical and a practical part . The inter-relationship of practical and theoretical - aesthetic and technical aspects are un-avoidable when it comes down to realities. This is clearly illustrated in the notes of Leonardo da Vinci. Plans for the organization of the treatise are vaguely formulated .
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  • Date Issued: 1986

Thank you Jesus

- Zionist Group, Composer not specified, Dargie, Dave

Thank you Jesus, Amen

- Zionist Church Choir, Composer not specified, Dargie, Dave

The "About to teach" course: an introductory orientation course for secondary teachers in training: an evaluation of student assessments

- Coughlan, Niall Sean

  • Authors: Coughlan, Niall Sean
  • Date: 1986
  • Subjects: Teachers -- Training of -- South Africa -- Eastern Cape High school teachers -- Training of -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:1910 , http://hdl.handle.net/10962/d1007057
  • Description: This piece of research is an attempt to evaluate the assessments made by secondary teachers in training of an introductory orientation course offered during the first seven weeks of the 1984 H.D. E. course in the Department of Education of Rhodes University. This course, the About To Teach (ATT) course, was introduced in an attempt to obviate some of the perceived problems that students experience in the initial months of their H.D.E. year. The course was first offered in 1982 and in both 1982 and 1983 it was assessed by the students. The evaluation of the assessments offered in those two years provided much of the background for this in-depth look at student assessments of the 1984 ATT course. Briefly, the course attempts to offer the students a stimulating, meaningful, interesting and enjoyable learning experience which will help them to orientate; prepare them adequately for their first teaching practice and the reception later of the offerings of the core theory discipline of Philosophy, Sociology and Psychology. The course itself is a piece of action research and its underlying assumptions are essentially humanistic in nature. Its planners have attempted to bracket as many assumptions as possible and to espouse only those assumptions which are basically positive in nature. It does not attempt to prescribe or offer any dogma which can or must be assessed in any formal sense; it attempts to meet the students from whatever stages in their development they are at when they arrive to commence their H.D.E. year; and it does not attempt to compel the students in any way whatsoever. It is a course which must stand or fall on its own merits. Since the researcher is himself an involved participant in the process, he felt that the completion of a detailed questionnaire and interviews with a sample of the students would be the most economical and the best means of obtaining data for as objective an analysis as possible. To further obviate the possibility of researcher bias all the responses collected have been included in the appendices so that the reader may satisfy him/herself that the interpretations made and conclusions drawn are reasonable. Briefly, the chief conclusion of this researcher is that the overwhelming majority of the students perceived the course as offering them a meaningful learning experience. In addition, it can be argued that the course is, in effect, a guidance course in that it appears to be preparing students for experiences which they still have to come across . Most are generally critical of other courses offered during the H.D . E. year and many make an appeal for, or suggest, a much more integrated approach along the lines of the ATT course . There is a definite appeal for a coherent H.D.E. experience which is meaningful and 'peoplecentred'. By no stretch of the imagination can the findings of this particular piece of research be generalised to any other context since it is very definitely specific in both context and setting. However the researcher is quietly confident that his conclusions and recommendations make a great deal of sense within the specific context of this study.
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  • Date Issued: 1986

The adsorption of chelating reagents on oxide minerals

- Bryson, Michael Andrew Walker

  • Authors: Bryson, Michael Andrew Walker
  • Date: 1986
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:20969 , http://hdl.handle.net/10962/5729
  • Description: This work constitutes a fundamental study of the interaction between chelating reagents and oxide minerals . The adsorption mechanisms have been elucidated for most of the systems generated by the oxides of copper(II) or iron(III) and chelating reagents octyl hydroxamate, N-phenylbenzohydroxamate, salicylaldoxime, 5-nitrosalicylaldoxime or 8-hydroxyquinoline. The results of the preliminary work on one of the systems, viz. the oxide-hydroxamate system, indicated that the classical type adsorption process, in which the reagent forms a uniform layer of chelate over the oxide surface was not applicable. Rather, the adsorption occurred via the formation of a discrete metal-chelate precipitate at the oxide surface. In order to better understand the associated with copper (II) oxide, adsorption process the oxide was recrystallized to produce a coarser material with a more uniform surface. This allowed the oxide surface to be viewed under the scanning electron microscope and also enabled the relative concentration of "surface" and "bulk" chelate to be assessed. A detailed investigation of the effect of the system variables; pH, conditioning period, concentration, temperature, surface area and dispersing reagent on the rate of precipitation of the copper chelate species of general form, Cu(chel)2' was made. In addition the chemical nature of the adsorbed species and the structural form of the precipitates were determined with the aid of infra-red spectroscopy and the scanning electron microscope. On the basis of these results a model has been formulated for the adsorption processes. In this model the adsorption dissolution, is considered to occur in stages: 1. Oxide dissolution, 2. metal complex formation, 3. Metal chelate precipitation at the oxide surface and 4. “bulk” chelate formation by post-precipitation processes. The precipitation process was examined in more detail by the study of the adsorption of chelate on copper metal. The results of this study showed that it was possible to relate the structural type of precipitate formed, ie. fibrous or platelike, to the degree of supersaturation of the metal complex in solution. Furthermore, it was found that the precipitate structure determined whether it remained attached to the surface or detached. Contact angle measurements of air bubbles on copper metal conditioned with chelate were related to the adsorption results in an attempt to isolate the optimum conditions for flotation of oxide minerals.
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  • Date Issued: 1986

The biology of the South African cliff swallow hirundo spilodera

- Earlé, Roy Anthony

  • Authors: Earlé, Roy Anthony
  • Date: 1986
  • Subjects: Hirundo pyrrhonota Birds -- Breeding -- South Africa Birds -- Behavior -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5631 , http://hdl.handle.net/10962/d1004927
  • Description: The general biology of the South African Cliff Swallow Hirundo spilodera was studied over a two year period in the central Orange Free State. This species is highly colonial, nesting mostly on man-made structures such as concrete road bridges. Adult birds were usually faithful to their breeding colony and very few individuals changed colonies. The Cliff Swallow had a surprisingly large vocal repertoire for a swallow and contact calls of the young were individually recognizable. Three species-specific ectoparasites parasitized the Cliff Swallow but none seemed to have a noticeable negative effect on the swallows. Breeding started earlier in larger colonies than in smaller ones and conspecific brood parasitism was a common feature in some colonies. Individual pairs made up to four breeding attempts per season. The findings of this study are compared with the available information on other members of the Hirundinidae and the advantages and costs of Cliff Swallow coloniality are discussed.
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  • Date Issued: 1986

The burgeoning family law and joint custody : inaugural lecture delivered at Rhodes University

- Schafer, I.D.

The conservation status of some unique plant communities in the Eastern Cape

- Everard, David Alexander

  • Authors: Everard, David Alexander
  • Date: 1986 , 2013-03-14
  • Subjects: Plant conservation -- South Africa -- Eastern Cape , Endangered species -- South Africa , Plant conservation -- South Africa -- Western Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4250 , http://hdl.handle.net/10962/d1007497 , Plant conservation -- South Africa -- Eastern Cape , Endangered species -- South Africa , Plant conservation -- South Africa -- Western Cape
  • Description: In response to a growing concern over the rising rates of extinction of the world's plants and of habitat destruction, studies of Southern African threatened plants were initiated in the 1970's. These studies, which have largely concentrated on Western Cape flora, led to the publication of "Threatened Plants of Southern Africa" by Hall et al., 1980, which attempted to list as many threatened or possibly threatened species as possible. It was however marred by a lack of recent herbarium records and detailed studies from many parts of the region, the Eastern Cape being one of these. In order to extend these detailed studies to gain a clearer picture of the numbers of threatened species in the Eastern Cape and evaluate the conservation status of Eastern Cape vegetation this project was initiated. Initially lists of possibly threatened and endemic taxa of the Eastern Cape were compiled from various sources. These listed taxa were then checked against herbarium records, all available information being filled onto index cards for filing purposes. This paper-based filing system was then transferred into a computer-based data bank to facilitate the efficient storage and retrieval of information. Results from this data bank show that there are 662 variously threatened plant taxa in the Eastern Cape, many of which fall into temporary categories which need to be clarified by investigation in the field. Primarily based on the above results, a table ranking the various vegetation types into an order of priority for investigations about conservation requirement was developed.Subtropical Thicket was found to be the vegetation type in most need of investigation and so an extensive phytosociological survey was carried out in the Valley Bushveld which forms the major portion of Subtropical Thicket in the Eastern Cape. Twelve sites were sampled for floristic and environmental variables along a rainfall gradient of between 300 mm yr⁻¹ and 1 000 mm yr⁻¹ and along a longitudinal gradient from the Buffalo River in the east to the Gamtoos-Kromme complex in the west. Floristic data W(re analysed using multivariate techniques of classification and ordination. A classification by two-way species indicator analysis revealed the Valley Bushveld to consist of two orders of thicket, the Kaffrarian Succulent Thicket containing the two suborders, Inland Succulent Thicket and the Coastal Succulent Thicket and the Kaffrarian Thicket containing Coastal Kaffrarian Thicket and Inland Kaffrarian Thicket. Ordina tion by detrended correspondence analysis also grouped sites according to these vegetation categories in a sequence along one axis, to which the rainfall gradient could be related. Variables such as diversity indices, numbers of endemics, numbers of threatened taxa and structural features were also extracted from the data and these were correlated with environmental variables by multiple regression analysis. Species richness and the percent woody component w\!re positively correlated with rainfall while endemism and percent succulent component were strongly negatively correlated with rainfall. Most of the other relationships were explained by interrelationships with rainfall. Finally the sites were evaluated according to floristic criteria indicative of conservation value. The Coastal Succulent Thicket appeared to have the highest conservation value mainly owing to high endemism, while Inland Kaffrarian Thicket was also important as it supports a high number of species. The thickets with high conservation value are therefore the thickets of coastal areas in the western parts of the Eastern Cape which receive a low rainfall and the thickets which receive a rainfall in excess of 800 mm. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 1986

The contribution of psychogenic factors limiting prolonged work performed at different relative intensities

- Rorke, Stafford Conroy

  • Authors: Rorke, Stafford Conroy
  • Date: 1986
  • Subjects: Physical fitness -- Measurement , Physical fitness -- Psychological aspects , Work measurement , Work -- Psychological aspects
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:5103 , http://hdl.handle.net/10962/d1004772 , Physical fitness -- Measurement , Physical fitness -- Psychological aspects , Work measurement , Work -- Psychological aspects
  • Description: This study investigated the physiological and psychological limitations to prolonged work performed at different relative intensities, through the use of an eclectic integrative methodology. Ten young male caucasian subjects (mean V0₂ max. 60,0 ml.kg⁻¹.min⁻¹ ± 7,9) were randomly exposed to treadmill runs at each of four relative intensities, namely 55%, 65%, 75% and 85% of V0₂ maximum, with the instruction to run to the point of subjective discomfort at which they were no longer willing to continue. Physiological measures of oxygen consumption (V0₂), heart rate (HR), respiratory exchange ratio (R) , minute ventilation volume (Vi), breathing frequency (Vf), tidal volume (Vt) and psychological measures of Ratings of Perceived Exertion (RPE), Perceived Thermal Comfo·rt (PTC), Perceived Pain and Perceived Fatigue were recorded throughout the protocol. The relative intensity was held constant by slight decreases in treadmill speed as subjects fatigued, and through feedback from an on-line oxygen consumption computer-aided data acquisition system. Significant increases in both physiological and psychological measures occurred with increases in relative intensity (p<0,05). HR and Vf increased overtime (p<0,05) whilst Rand Vt decreased over time (p < 0,05) . All psychological ratings increased in intensity over time (p < 0,05). Mean endurance times to exhaustion were 243 minutes ± 70 at 55% relative intensity, 159 minutes ±37 at 65%, 96 minutes ±25 at 75 % and 23 minutes +- 8 at 85%, being within the range reported by earlier researchers . A regression equation for prediction of endurance time given a known relative intensity was developed for this sample: % V0₂ max. = 117,8 + (-10,6 x LN (time)) (where r = -0,91) Convergence rankings indicate the greater contribution of local factors in the overall gestalt of perceived exertion, pain and fatigue, with biomechanical limitations to prolonged work (running) strongly implicated . High inter correlations between psychological rating scales suggest the use of the scale considered most applicable to the task at hand and the psychological response measure required. A coefficient of multiple correlation of 0,94 established the close interrelationship amongst the physiological and psychological parameters measured. Pre- and post-test Fatigue Cluster Analysis questionnaires indicated that the most important clusters contributing toward the sensation of fatigue and subsequent decision to cease activity were Task Aversion and General Fatigue (r = 0,96), followed by Leg Fatigue and Thirst. Motivation, the task at hand and an attainable goal appear to be important considerations in prolonged work performance. Relative intensity appears a valid tool for use in prolonged work studies due to its high predictive capacity for endurance performance times (r=-0,91). It is concluded that workloads considerably below 55% of maximal aerobic capacity are indicated as acceptable workloads for an 8 hour working day.
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  • Date Issued: 1986

The contribution of William Gurnall (1616-1679) to the puritan concept of spiritual combat, with special emphasis on the role of faith

- Van Zyl, Frederick William James

  • Authors: Van Zyl, Frederick William James
  • Date: 1986
  • Subjects: Gurnall, William, 1617-1679 , Puritans , Faith , Spiritual life -- Christianity -- History of doctrines
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:1223 , http://hdl.handle.net/10962/d1003916
  • Description: The Central figure in this thesis is William Gurnall M.A. (Cambridge) who lived from 1616 to 1679. He was the Rector of the Lavenham Parish church for 35 years, 1644/45-1679. He was one of the few Puritans who remained in the Established Church after the 1662 Act of Uniformity had been promulgated. His 'The Christian in Complete Armour' is one of the greatest practical-pastoral works to come from the pen of any Puritan. It is firmly based on Calvinistic theological principles. While holding common beliefs in many areas, Gurnall nevertheless was at odds with his fellow Puritans over certain crucial issues that directly affected his attitude to the Puritan revolution. His analysis of the person, being, nature, wiles, strategies and weapons of the Christian's great enemy and description of the Christian's resources such as the role of the shield of faith in its multiple uses, which constitute an important contribution to pastoral theory and practice are shown to arise out of Gurnall's theological stance, his own personal history, the history of East Anglia and of Lavenham in particular; his reflections on the 'Days of Great Confusions' and his deep concern for the breakdown in orderly society and the decline of genuine piety in the church. Basically we will concentrate on three issues: First. The real nature and locus of the Christian's spiritual warfare. Second. -- The means used for his investigation, namely, an examination of the person, power, methods and wiles of the Christian's great enemy and the vital role of the shield of faith. -- Third. His conclusions.
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  • Date Issued: 1986
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