Sediment linkages in a small catchment in the Mount Fletcher southern Drakensberg region, South Africa
- Authors: Mzobe, Pearl Nonjabulo
- Date: 2014
- Subjects: Soil erosion -- South Africa -- Mount Fletcher , Soil conservation -- South Africa -- Mount Fletcher , Soil degradation -- South Africa -- Mount Fletcher , Food security -- South Africa , Wetland management -- South Africa -- Mount Fletcher , Watersheds -- South Africa -- Mount Fletcher
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:4879 , http://hdl.handle.net/10962/d1013224
- Description: Soil erosion is a persistent problem that requires continued control efforts as agricultural land loses productivity and communities dependent on the land become increasingly vulnerable to decreased food security. The negative effects of soil erosion in Khamopele River catchment, in the Mount Fletcher southern Drakensberg region of South Africa, are manifest in extensive gullying and wetland loss. Soil erosion has resulted in siltation in a recently constructed dam and the alteration of aquatic habitats. This research was undertaken to identify the sources of eroded sediment in the small upper catchments of the Mzimvubu River catchment to inform broader catchment management strategies. The scale of erosion was quantified using field surveys of gully extent and form. Environmental magnetic tracing techniques were used to determine the sources of eroded sediment in Khamopele River and upper Tina River catchments. The radionuclide ¹³⁷Cs was used to determine soil loss over a 55 year period in Khamopele River catchment. The Landscape Connectivity framework was used to describe the sediment source, pathway and sink interactions at sample area level. Results indicated that historical and contemporary land management practices such as uncontrolled grazing, grassland burning and furrows promoted soil erosion in the catchment. Soil erosion was most pronounced in the Taung sample area where there was extensive gullying, tunnelling and subsurface erosion. Environmental magnetic tracing results indicated that there were clear differences in source areas. Despite its prevalence in the area, gully erosion was not shown to be a major source of sediment to downstream sinks. Topsoil and hillslope derived sediment were shown to be mobile in the catchment, suggesting that sheet erosion processes were dominant in the catchment. Radionuclide tracing studies showed that at least 20 cm of soil had been eroded from the Khamopele River catchment surface since 1956. This research has shown that it is possible to distinguish source areas of erosion in the catchment by matching catchment mineral magnetic signatures to those in sink areas. This means that rehabilitation projects can use resources efficiently as the areas needing the most attention can be identified.
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- Date Issued: 2014
The machine and painting: an investigation into the interrelationship(s) between technology and painting since 1945
- Authors: Hennig, Sybille
- Date: 1986
- Subjects: Art and technology Art, Modern -- 20th century -- History
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2468 , http://hdl.handle.net/10962/d1009435
- Description: Introduction: We, i.e. contemporary Western man, live in a society which has increasingly embraced Science and Technology as the ultimum bonum. The Machine, i.e. Science and Technology, has come to be seen as an impersonal force, a New God - omniscient, omnipotent: to be worshipped and, alas, also to be feared. This mythologem has come to pervade almost every sphere of our lives in a paradigmatic way to the extent where it is hardly ever recognized for what it is and hence fails to arouse the concern it merits. While some of the more perceptive minds - such as Erich Fromm, Rufino Tamayo, Carl Gustav Jung, Konrad Lorenz and Arthur Koestler, to mention but a few - have started ringing the alarm bells, the vast majority of our species seem to plunge ahead with their blinkers firmly in place (more or less contented as long as they can persude themselves that these blinkers were manufactured according to latest technological and scientific specifications). Man’s uniquely human powers - his creative intuition, his feelings, his moral and ethical potential, have become sadly neglected and mistrusted. Homo sapiens – “homo maniacus” as Koestler suggests? - is now at a crossroads: he has reached a point where the next step could be the last step and result in the annihilation of man as a species. Alternately, avoiding that, there is the outwardly less drastic but essentially equally alarming possibility of men becoming robots, while a third alternative has yet to be found. While it does appear as if a lot of young people, noticeably among students, have started reacting against the over mechanization of life, these reactions often tend to follow the swing-of-the-pendulum principle and veer towards the other extreme, throwing out the baby with the bathwater and falling prey to freak-out cults in a kind of mass-irrationalism, rejecting science and technology altogether. Artists who by their very nature perhaps are particularly sensitive - in a kind of seismographic way - to the currents and undercurrents of their age, have become aware of the effects of science and technology on our way of living, and many of them have in one way or another taken a stand in relation to the position of man in our highly technological world. Looking at the art produced over the last four decades, it is truly astonishing to what extent our changed world reflects in our art - a world and a Weltbild very different from that of our ancestors even just a few generations ago. The purpose of the present study is to survey some of the observations and commentaries that painters and certain kindred spirits from the sciences over the last few decades have offered, in the hope of, if not answering, at least defining and posing anew some of the questions that confront us with ever-increasing urgency.
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- Date Issued: 1986