Changes in postural stability following sensory manipulation were investigated among Parkinson's disease patients and healthy older adults. Sixteen Parkinson's disease patients (PD; mean age 68.2 + 2.7 years) and sixteen older adults (control; mean age 67.6 + 2.6 years) performed quiet standing trials that progressed through baseline, sensory manipulation, and reintegration. Postural control following visual deprivation was assessed following alternate removal and reinsertion of visual information. Postural recovery following sensory incongruence was assessed following the termination of visual, somatosensory, and visuosomatosensory incongruence. PD patients' balance was disrupted following visual deprivation, and was initially disrupted when visual information was returned. PD patients' pstural recovery was comparable to control subjects when sensory incongruence ended. These findings indicate that situations of visual deprivation in particular are initially disruptive for PD patients, and imply initial difficulty for sensory reorganization in these patients. Our results provide insight into environmental situations imposing greater fall risk among the parkinsonian population. / xii, 81 leaves ; 29 cm.

The effects of postural threat on gait initiation and steady state gait among Parkinson’s disease (PD) patients and age-matched adults were examined. Ten healthy adults (CTRL; mean age= 68.8 ± 8.4, range 56-80 years) and ten PD patients (PDOFF / ON ; mean age= 69.7 ± 10.3, range 54-81 years) initiated gait and continued with steady state walking along a walkway of two different height conditions. PD patients were first tested in a non-medicated state followed by testing in a medicated state. The results showed that gait initiation and steady state gait deficits inherent to PD are exacerbated in a postural threatening environment. As well, medication efficacy for overcoming parkinsonian deficits may be context dependent. These findings confirm the dynamic nature of movement deficits characteristic of parkinsonian patients and provide empirical evidence for specific environments that can create movement difficulties for people with PD. / x, 59 leaves : ill. ; 29 cm. --

No description available.

No description available.

The impact of development on coastal ecological processes within the coastal zone is often noted as being of ecological concern, due to the suggested destabilization of dune systems as a result of construction activities and post construction impacts such as stormwater disposal, trampling and other artificial influences on, in particular, the plant ecology of the frontal dune systems. Given that the stability of frontal dune systems along the Kwa Zulu Natal north coast is often attributed to the maintenance of vegetation and seral progression on such systems, the identification of changes in dune plant communities that may arise from the influence of proximal or adjacent activities was sought to be identified. Utilising data collected from a number of sites in the Kwa Dukuza Municipal area, the classification and ordination of environmental and botanical species information collated over approximately 6 months was undertaken. The results of this investigation indicate that: Species composition differs in terms of richness and abundance in the three frontal dune vegetation zones sampled. 2 3 4 5 Some species occur in all three zones and others are confined to one zone only. Bearing and the associated influence of wind, the slope and length of the beach, and the steepness ofthe dune face all influence the species composition at any particular site The influence of anthropogenic activities on dune synusia is such that human influence on one species may disrupt associations between species and may result in attenuation or '" reversal of seral movement. Anthropogenic impacts influences species composition at different sites by causing some species to decline abundance or disappear from a site and others to invade or oust established species. In Zone I the species that appears to be most affected by human activity is Gazania rigens, which appears to dominate in sites of high human activity, at the expense of Sporobolus virginicus. In Zone IT under high human activity species such as Cynanchum obtusifolium, Rhoicissus digitata and Sporobolus virginicus dominate, while the woody species Mimusops caffra and Eugenia capensis, as well as the liane Gloriosa superba appear to decline or be ousted from this Zone. In Zone Ill, Asystasia gangetica, is a dominant species where low to moderate human impacts are encountered, while where human impacts are high, species common to Zone I, such as G rigens may become prevalent, ousting A gangetica and grasses such as S virginicus may be ousted by more competitive species such as Stenotaphrum secundatum. It is thus concluded that human activities in and around the frontal dune system may be influential in re-inforcing aeolian impacts on sites with bearings affected by strong prevailing winds. / Thesis (M.Sc.)-University of KwaZulu- Natal,Durban, 2004.

This study is concerned with the physical and human causes of soil. erosion. Some quantitative information on the magnitude of soil erosion for different ecoregions in South Africa is available. However, such quantitative data is available only from a few sites. One objective of this thesis is to add to the existing data. Site specific data is provided for the two study areas in the Eastern Cape Province, namely, Chani area in Mt Frere and Brooks Nek area in Mt Ayliff. A comparison is made between the physical and chemical characteristics of the soils found in both study areas. The spatial and temporal extent of the erosion problem is also given. Another major objective is to evaluate the soil rehabilitation measures used at these two areas. An evaluation of the relevance and efficiency of the erosion control measures is made. (For gully erosion especially, the present study provides an evaluation of the suitability and effectiveness of the gully control mechanisms adopted.) Most importantly, a third objective of this study is to investigate the awareness and attitudes of the members of the communities affected by the erosion problem. Among the many different factors found to be important in the causal nexus that results >f in soil erosion, it has been found that many of the problems originate from social causes, like that of too large a population for the limited available resources. Added to this, factors like poor development programmes, bad agricultural practices, bad road management, have exacerbated the erosion problem. In other words, from research and interviews conducted in the study areas, erosion problems linked to recent political policies; to farming and to other practices were found to be associated, inter alia, with the shortage of land, unemployment, the lack of the necessary farming equipment, overgrazing and so on. To stress the point, the five important factors contributing to erosion were identified as an over exploitation of the land resource for basic needs, bad road management, floods, drought, and concentrated flow on furrows made by both on and off-road vehicles. We noted that another important feature of this thesis is to give an account of the psychological attitudes of individuals living near the areas affected by erosion, Respondents to interviews and to questionnaires generally agree that there has been a lot of change in their natural and man-made environments, especially in terms of gully development and vegetation reduction. However, there is a disturbing level of ignorance concerning the causes and consequences of erosion. When asked to estimate the date of gully initiation in Brooks Nek, for instance, none of the respondents could give even rough estimates or a specific incident leading to the current dominant erosion problem. The general attitude towards the problem in their midst was one of indifference. The general belief is that erosion is caused not by themselves but by natural phenomena. Further, most respondents thought it is someone else's (e.g. government's) responsibility to ameliorate the harmful consequences associated with land deterioration and soil loss. The data for this thesis have been obtained through surveying the landscape directly over a three-year period (1994-6), and by using aerial photographs for 1982 (Mt Frere site) and 1993 (Mt Ayliff site). Detailed analysis was undertaken of chemical and physical characteristics of soil at both sites. In addition, quantitative and qualitative surveys of people in the area were attempted; to ascertain their understanding and contribution to the problem. The implications, as shown from the results of this investigation, are that the soil erosion problem at both study areas are largely independent of soil characteristics. On the contrary, this study will show that human practices are the major initial causes for soil erosion in all the cases investigated. It was found that over the years, the land use practices in both sites have changed significantly. Factors accelerating the development of erosion forms at Brooks Nek, for instance, include the footpaths and stock trails. In contrast, artificial contouring and poor gabion layout are the major causes in Chani. However, it must be mentioned that it is not always easy to separate the effects of human from natural causes. Once the effects of human activities exceed the optimum limits of soil resistance and resilience, erosion starts. Then erosion acceleration will not necessarily be confined to the original cause(s). Natural storms and floods, or even drought will contribute in accelerating the erosion rates. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

No description available.

No description available.

No description available.

In the context of growing concern for the potential impact of climate change, climate governance mechanisms are employed by nation states aiming to influence environmental actions of various actors. Promoting green behaviour of individual citizens is one of the current climate governance approaches. Furthermore, increasing attention is given towards the younger generations, as they will have to bear the consequences of climate change. Empowering young people to act against climate change is, therefore, important. This study aims to explore whether ecological citizenship among young people in Durban, South Africa, could be a valuable component of climate governance. It will do so by: 1) exploring how young people conceptualise climate change, 2) how they understand and experience citizenship, 3) whether they possess features of ecological citizenship. This research consists of a qualitative study based on semi-­‐structured interviews with eighteen young individuals. The conceptual tools of practice theory and citizenship, that incorporate aspects of ecology and youth, are utilised for understanding the empirical study. The findings suggest that young people in Durban have a vague understanding of climate change-­‐related concepts. Furthermore, it shows a gap between the understanding and the experience of citizenship. The youth comprehend citizenship with its features of rights and obligations; however, their experience of citizenship is largely dominated by detachment from politics, a sense of exclusion, and a lack of authentic opportunities to play out citizenship activities. Lastly, everyday practices of young people reveal a limited range of environmentally friendly actions accompanied by a moderate sense of agency in relation to environmental problems. This study shows that in order for young people to be able to act as ecological citizens, there are several structural constraints that need to be transformed into opportunities. This research suggests that there is a need to: 1) enable citizenship options for young people, 2) establish practical alternatives for sustainable behaviour. This study argues that providing such structural opportunities has the potential to develop young citizens that can act in an environmentally friendly way, without providing any guarantee for green behaviour. However, the potential for such behaviour is nevertheless greater with structural opportunities, rather than constrains. / M. Dev. Studies University of KwaZulu-Natal, Durban 2013.