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The influence of anthropogenic impacts from development and human activity in and around foredune plant communities along a portion of the KwaZulu-Natal coastline.Bundy, Simon C. January 2004 (has links)
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.
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Patterns and economic impacts of livestock predation in rural communities bordering Makgadikgadi Pans National Park in Botswana.Dikobe, Leonard Mogopodi. January 1997 (has links)
Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more Northern Botswana's rural agricultural settlements bordering national parks and game reserves. In two study areas (Khumaga and Gweta, bordering Makgadikgadi Pans National Park), spatial, temporal and prey-type patterns of livestock predation were assessed. Cattle, goats, horses, donkeys and sheep were the key livestock types. Lion, leopard, cheetah, wild dog, black-backed jackal, spotted hyena and the Nile crocodile (occurring only in Khumaga) were the key predators. Oral interviews with farmers in these villages provided insights into the patterns and impacts of livestock predation on rural economies. Khumaga's livestock predation scenario is dominated by lion predation on cattle, goats and donkeys, leopard predation on small stock and calves, and crocodile on goats. Wet season predation rates were higher than dry seasons', except for spotted hyena, black-backed jackal and leopard. Leopard and black-backed jackal are dominant small stock predators in Gweta. lion are the main cattle and donkey predators (though at lower frequencies). Dry season predation rates are higher. Farmers who own more livestock appear to lose more cattle than those who own few. Gweta contrasts with Khumaga, having livestock predation highest during dry seasons, less reduction in livestock sales and a lower value of pending compensation claims. These predation patterns synchronise with movements of zebra and wildebeest to and from the Boteti river. Losses of livestock affect the utility derived from livestock and monetary gains from direct sales. Costs due to loss of biodiversity, though not quantified, add to those borne by the State through predator control. Both the State and the farmers loose. These losses reduce the incentives of the latter to conserve species that contribute reduction in their returns. The issue of State expenditure on predator control illustrates the possible need for re-direction of such funds into farmer-based predator control, much as an integral part of the current southern African trend of community-based natural resource management. Key words: livestock predation, predator control, economics, conservation, Botswana. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1997.
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Theatre for change : climate change knowledge translation in a peri-urban context.January 2009 (has links)
The negative effects of climate change are contributing to the growing complexity of issues challenging livelihood sustainability and are further threatening already vulnerable communities. In response to these challenges, new means of conceptualising problems needs to be investigated so as to adequately deal with the multi-dimensional issues that arise. Central to this are means of communication and participatory interaction with vulnerable communities in the development of adaptation strategies. Theatre has been identified as an effective means of inspiring change through a process of critical self-reflection and personal empowerment, making it a pertinent tool for climate change communication.
This research demonstrated how theatre was used in the process of knowledge translation for climate change adaptation within the community of Amaoti, KwaZulu-Natal. Knowledge was gathered from the community through two processes; a vulnerability analysis that examined five main vulnerability components, and a theatre engagement process that resulted in the production and performance of a play, Fish Out of Water. The vulnerability analysis – conducted through a selection of participatory rural appraisal tools - determined that the community was particularly vulnerable with regards to water. In addition to this, it faced a series of social challenges, including high levels of disunity, high crime rates and poverty. This analysis was central to the development of adaptation strategies, which Fish Out of Water communicated through its performance, contextualised in the translated vulnerability knowledge.
Responses to the play were analysed, indicating that the climate change information had been successfully communicated and that theatre itself was an effective means of communication. In addition to this, it was determined that this process had also contributed a greater sense of awareness of social issues and had inspired people to take actions to change their behavioural patterns. New social considerations were made, contributing to a comprehensive understanding of situational dynamics that could inspire change.
While positive conclusions were drawn from this with regards to the use of theatre in climate change communication, significant challenges were experienced during the process indicating a series of more fundamental issues that need to be addressed. High levels of apathy, difference of value systems and constraining family-dynamics need to be taken into account if the implementation of such processes is to be successful. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Towards a macroinvertebrate sampling protocol for monitoring water quality of wetlands in South Africa.Bowd, Rebecca. January 2005 (has links)
The degradation of wetlands and loss of their associated ecosystem services is widely recognised in South Africa, however, at present there is no standard method of biologically assessing wetland health in this country. Internationally, particularly in the U.S.A and Australia, wetland bioassessment techniques using macroinvertebrates are well established. A number of these wetland bioassessment protocols have been derived from local river biomonitoring techniques, as there is a belief that river and wetland ecology and macroinvertebrate assemblages at family level are similar. However, some authors consider wetland macroinvertebrate assemblages and ecological processes to differ greatly from those found in rivers, and believe that such techniques are not transferable. South Africa has a well established macroinvertebrate biomonitoring protocol for rivers called SASS5 (South African Scoring System Version 5). This study is a preliminary investigation into the extent to which the SASS5 scoring system is applicable to the assessment of nutrient enriched wetland water quality.
Macroinvertebrates are particularly suitable as biomonitoring tools: they respond to a variety of stressors, have life cycles that allow for integrated responses to episodic pollution, and are relatively easy to identify to family level. When selecting wetlands for the development of a biomonitoring protocol, wetlands should all be of the same; classification (Le. palustrine), geomorphological and climate setting, hydrological regime and dominant vegetation class. Sampling was restricted to sedge-dominated palustrine wetlands in the midlands of KwaZulu-Natal, with similar hydro-geomorphological settings. Due to wetlands and rivers having different biotopes (e.g. no riffles present in wetlands), the SASS5 sampling protocol could not be used, thus a pilot investigation was undertaken to derive a suitable sampling technique for \
collecting a representative and diagnostic sample of aquatic macroinvertebrates from a wetland. This technique was developed based on published methods. Both sweep net and activity trap sampling were conducted, and each evaluated for their effectiveness at macroinvertebrate collection. Sweep net sampling was tested over a range of sweep intensities (2-6 sweeps), and activity traps were placed at four different depths: at the water surface, just below the surface, 0.10.15m below surface and on the substrate.
A total of 32 taxa identified to family level were identified in the samples. Taxon diversity and composition did not differ in the activity traps placed at the four depth locations. Taxon diversity did not differ significantly between different
sweep intensities; however there was a significant difference in taxon composition between the different sweep intensities and between activity trap and sweep net samples (p<0.05). Sixty-eight percent of taxa appeared more frequently in sweep net sampling compared to activity trap sampling. Six taxa were found exclusively in sweep net samples, and two taxa were recorded exclusively in activity traps. There was no trend in either method collecting more or missing any unique trophic group. In conclusion, activity traps are not required to supplement sweep net data, and a technique using a sweep net with a sweep intensity of five would be suitable to collect a representative sample of wetland macroinvertebrates. Using the derived technique, four reference and three wetlands impacted by dairy effluent were sampled. Six macroinvertebrate samples were collected from each of the seven wetland, together with data for selected physico-chemical variables, macrohabitat condition, biotope suitability and organism detectability. For each sample, the macroinvertebrates were identified and assigned a predetermined SASS5 tolerance score between 1 and 15, with higher scores indicating increased sensitivity to poor water quality. 11
A total of 39 taxa, identified to family level, were collected during sampling. SASS5 scores ranged from 15-82. Five of the wetlands had mean SASS5 scores of between 46 and 59. Five of the wetlands had an intra-wetland SASS5 score range greater than 30. ASPT values ranged from 3.3 to 5.5, and few high scoring (~8) taxa were collected. There was no significant difference in SASS5 scores between samples collected above, at and downstream of an effluent discharge point within the same impacted wetland. SASS5 scores for reference wetlands were also not significantly higher than those recorded for impacted wetlands. Comparison of ranked SASS5 scores and environmental data did suggest a relationship between the variables, but was not significant. Based on the SASS5 score water quality guidelines, all sampled wetlands were considered to have impacted water quality; however, this was not supported by the macrohabitat and physico-chemical results. Possible reasons for the low SASS5 scores include: the lack of 'stones in/out current' biotopes in wetlands, lower levels of dissolved oxygen present compared to rivers, and the limited detectability of organisms due to large amounts of substrate in the samples. A wetland adaptation of SASS5 would require the reassignment of modified scores to certain taxa based on their distribution in wetlands of varying water quality. The SASS5 score level of 100 and the ASPT value of 6 (as specified in the SASS5 score water quality guidelines) were found to be inappropriate for wetlands. It is suggested that, either the range of taxa tolerance scores be increased (1 to >15), or the score level of 100 be lowered. The ASPT value should also be reduced. Although SASS5 appears unsuitable for assessing wetlands, variations in taxon composition between sampled wetlands, identified through CA analysis, suggests that macroinvertebrates are responsive to changes in wetland condition, and thus have potential as indicators of wetland water quality. Nine taxa responsive to the presence of nitrogen have been identified as being potentially good indicators. iii Further research should focus on the testing of SASS5 throughout the year, in a range of wetland types, and in wetlands moderately to severely impacted by pollutants other than dairy effluent. It is recommended that a habitat or biotope index be developed and used in conjunction with any future wetland macroinvertebrate bioassessment protocols. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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The anthropogenic impacts of urbanization and industrialisation on the water quality, ecology and health status of the Palmiet River catchment in Durban, KwaZulu-Natal.Naidoo, Kushela. January 2005 (has links)
Water, a fundamental and irreplaceable resource, is an all-pervasive issue that underpins the social fabric of every society. Rapid population growth and expansion of human activities increases the amount of waste and pollution generated and many local authorities are encountering serious water pollution problems, often concentrated in the lower reaches of catchments and adjacent coastal areas. This problem is predominantly acute in urbanized catchment areas, where waste is concentrated into localized areas, and the authorities are constantly under pressure to provide adequate management and mitigation measures. The Palmiet River system, located in the northern fringe of the city of Durban and draining the highly industrialized Pinetown region in KwaZulu-Natal, South Africa, illustrates a system that has been altered due to human impacts, particularly in its headwaters where the industrial sites are located and, in the lower catchment where a densely populated informal settlement occurs. A range of chemical and biotic indicators were monitored seasonally and these confirm the influence of the aforementioned human impacts on the quality of the Palmiet River system. Results from the present study were compared with studies conducted over a period of two decades and clearly demonstrate a pattern of increasing pollution loads for the upper and lower parts of the catchment. This study confirms that the Palmiet River is severely degraded in its lower reaches whilst the middle reaches of the catchment where a nature reserve is located is still in a fairly pristine condition. Additionally, the Palmiet River issues discussed in this thesis have direct impacts on the estuarine and adjacent marine ecosystems. / Thesis (M.A.)-University of KwaZulu-Natal, Durban,2005.
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An investigation into the classification of river environments using GIS : the case of KwaZulu-Natal rivers.Sebake, Malete Daniel. January 2005 (has links)
According to the National Water Act No. 36 of 1998 (DWAF 1999), classification of the water resources in South Africa is the initial step towards the implementation of protection or management programmes. This study reviews different methods and systems of classifying river environments, in order to recommend a convenient, efficient and flexible classification
scheme for describing the conditions of river environments. To meet this challenge, the study proposes the use of Geographical Information System (GIS) as a tool to link different controlling variables of river environments and thereafter analyse their spatial relationships. The study supports the use of GIS in river environment classification, with special emphasis on its functionalities that make it possible to explore and manipulate data interactively and easily. The GIS allows the user a flexible way to analyse the geomorphologic and ecological controlling variables of the river system. Thus , it enables different arrangements of these controlling variables for a number of classification purposes. The methodology used involves the GIS (database) analyses and map analyses to explore the relationships between
geomorphologic and ecological controlling-variables of the river ecosystem.
A case study of the KwaZulu-Natal Rivers demonstrates that valuable information for river environments could be derived from available geomorphologic and ecological datasets using methods of analyses within the GIS. In addition, the case study illustrates that it is possible to develop a working classification scheme for a particular purpose. The developed
classification scheme can be improved by considering influential factors such as, the use of up-to-date datasets, consistent projection parameters and relevant scale. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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Land use changes within the uMngeni and Mpofana municipalities : an assessment of environmental impact assessments, 1999-2010.Bhikraj-Kallicharan, Reka. January 2010 (has links)
Land is a non-renewable and finite resource which comprises a variety of ecosystems that support biological diversity and provide food, shelter and raw materials to society. With a multitude of land uses competing for this precious resource, the land is becoming fragmented, altered and transformed. Land transformation has been acknowledged as a key contributor to the degradation of the environment and has serious implications for poverty, food security and biodiversity. This research focuses on land use changes within the uMngeni and Mpofana municipalities in KwaZulu-Natal. The main objectives were to critically review Environmental Impact Assessment (EIA) decisions and document those EIAs received and finalised over the period 1999 – 2010, spatially define the location of decided EIAs, determine the types of EIA decisions issued, characterise the type and extent of land uses, describe patterns of land use change and identify the key factors responsible for changes in land use. During the research period a total of 337 EIA applications were received and 332 EIA applications were completed in the uMngeni Municipality and 182 EIA applications were received and 178 completed in the Mpofana Municipality. The types of EIA decisions issued consist of Records of Decisions, Environmental Authorisations, Exemptions, Withdrawals and Commencements. The key classes of land use changes that have occurred in uMngeni Municipality are Agriculture to Residential, whilst within the Mpofana Municipality the predominant land use change occurred within the Agricultural land use category. For both municipalities the Agriculture to Residential land use category experienced the greatest extent in land use change. In authorising EIA applications, the predominant key decision factors were based on the comments from Ezemvelo KwaZulu-Natal Wildlife and Amafa aKwaZulu-Natali. In refusing EIA decisions the findings of various specialist studies, incompatible land uses and land use planning initiatives were the predominant key decision factors. The conclusions are that agricultural land is being transformed for use as nonagricultural activities specifically that of residential use. The recommendations include the need for accurate record keeping of data and information pertaining to EIAs and the integration of spatial planning tools and initiatives including Geographical Information Systems in the review of EIAs to improve decision making. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
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An evaluation of the Riparian Vegetation Index (RVI) in KwaZulu-Natal.Clarke, Simon. January 2003 (has links)
No abstract available. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
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Population survey of Crocodylus niloticus (Nile crocodile) at Lake Sibaya, Republic of South Africa.Combrink, Alexander Stanislou. January 2004 (has links)
The Greater St Lucia Wetland Park (GSLWP) World Heritage Site, is one of the most important remaining protected areas for the conservation of Crocodylus niloticus (Nile crocodile) in the Republic of South Africa Although crocodiles are present at low densities in some of the wetlands throughout the GSLWP, at Kosi Bay and Lake Sibaya, the majority is found at Lake St Lucia Concern about the status of the crocodile population at Lake Sibaya prompted a quantitative assessment of the present situation to direct appropriate management action to secure the future viability of this population Due to the complex nature of crocodile surveys, and the paucity of available scientific literature in South Africa, a literature review of global crocodilian survey techniques provided the basis for a survey strategy to determine an index of relative abundance of the crocodile population at Lake Sibaya The population was estimated in 2003 through aerial and spotlight surveys and nest surveys were conducted in 2003 and 2004. The highest count dwing the 2003 aerial surveys was 36 crocodiles, suggesting a decline of 66% during the past 13 years in the population index based on earlier surveys. Sixty five crocodiles were cowlted during the spotlight surveys, 72% more than the highest aerial count (excluding hatchlings), which indicates the importance of using a combined survey approach. A correction factor of 1.72 was calculated for future aerial surveys and the population is estimated at 112 crocodiles, \\-ith a variance of22.49 and standard error of 4.47. Three nests were found during the 2003 nest survey, but none during 2004. Crocodiles rarely produce every year in the wild, and the Lake Sibaya population might display a low reproductive frequency, similar to the nearby Lake St Lucia population Sixty three potential nesting areas were identified and evaluated in terms of their relative suitability for nesting. These sites could play an important role in increasing the population to support a sustainable use progralllffie at Lake Sibaya. Despite legal protection, the population is clearly under threat as a result of direct and secondary pressures. To secure the future viability of this population, I recommend that Ezemvelo KZN Wildlife develop an integrated crocodile management plan through collaboration with The Greater St Lucia Wetland Park Authority and the local communities adjacent to Lake Sibaya, where the conservation and increase of crocodiles will benefit the communities that are dependent on the lake for their daily livelihoods. The likely alternative might be extinction of this important predator from the largest freshwater ecosystem in South Africa's first World Heritage Site. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.
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A framework for effective urban stream corridor management : a case study of Pietermaritzburg. Component A.De Lange, Marthinus Arnoldus. January 2003 (has links)
Not only does urbanisation have a negative impact on the establishment of natural open
space areas but also has serious implications for urban stream corridors (USCs), the focus of
this study. For the purpose of this study USCs are defined as the aquatic, the riparian and the
terrestrial zone. The principle objective of this study is to develop a set of policies, based on
international and local experiences (Pietermaritzburg Metropolitan Open Space System) to
guide municipalities in implementing effective USC management practices.
The literature review lead to the identification of both the value of USCs and the threats
thereto. The value of USCs includes habitat and biodiversity, purification, amenity, cultural,
recreational and eductional valueas well as flood attenuation value. Conversely, threats to
USCs include the impacts of urbanisation on stream hydrology, erosion, decline in water
quality, loss of natural open space (NOS), alien infestation, littering and unnatural fence
barriers. Urban stream corridor management is subject to specific legislation, municipal
capacity and importantly, public involvement, which were also evaluated.
This process lee;td to the establishment of a conceptual framework containing the critical
considerations associated with USC management such as the value of USCs for nature and
man, the need for public involvement, effective implementation structures supported by
implementation policies and the integration of use management in urban planning. Key to
the success of USC management is public involvement.
As a consequence, the methodology included a survey to be undertaken with 40 urban
riparian households along two streams in Pietermaritzburg to establish their opinion regarding
natural open spaces (NOSs) and USC management. A reconnaissance survey of two
streams was undertaken to inform the questionnaire and later debate on the issue. The
results from this exercise together with the findings of the interviews with stakeholders in the
USC management process will form the basis for the establishment of an USC management
policy, which will be contained in a separate report (Component B). / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
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