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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

A review of stakeholder interests and participation in the sustainable use of communal wetlands: the case of the Lake Fundudzi catchment in Limpopo Province, South Africa

Silima, Vhangani January 2007 (has links)
Many rural South African people depend on natural resources for their survival. Wetlands provide some of those natural resources. These are presently are under pressure due to high demand, overexploitation and poor land management. The history of South Africa has been characterised by exclusion of local communities in the process of decision-making and general management of natural resources. Participation of all stakeholders is crucial for successful sustainable natural resource management. Various South African departments are engaged in a number of strategies for promoting meaningful participation of local communities. The South African laws promoting protection and sustainable use of natural resources incorporate democratic principles that require high level of participation from resource users, local communities in particular. Most of the participation techniques used are focused on satisfying political mandates and do not respond to the social context of the resource users. The aim of the study was to review the participation of stakeholders in the project of promoting the sustainable use and protection of the Lake Fundudzi catchment. The idea was to probe stakeholder interests more carefully, and to research tensions that arise in the participation process, using qualitative methodologies. Through the use of questionnaires, observations and document analysis stakeholders’ interests were identified to assess their influence in the process of participation of local stakeholders. The review of stakeholders’ participation in the Lake Fundudzi Project showed that stakeholders’ interests are crucial for meaningful local community participation, communication and education influence. They enable meaningful participation and empowerment. A multi-stakeholders approach enables stakeholders to share roles and responsibilities and the participation process offers an opportunity for local stakeholders to participate democratically in the Project. Power relations affect stakeholder participation, capital dependant participatory initiatives are likely to be at risk, participatory processes are likely to promote the empowerment and knowledge exchange amongst stakeholders, the views of local stakeholders are not always considered by outside support organisation and multi-stakeholder participatory approaches enable the initiative/activity/project to achieve its objectives.
12

Assessment of the long-term response to rehabilitation of two wetlands in KwaZulu-Natal, South Africa

Cowden, Craig January 2018 (has links)
Assessing the outputs and outcomes of wetland rehabilitation activities is recognised by the 'Working for Wetlands' programme in South Africa as important, but to date has been limited. An assessment of the ecological outcomes and the structural outputs of the Working for Wetlands rehabilitation implemented in the Killarney and Kruisfontein wetlands, KwaZulu-Natal, in 2005 was undertaken. The assessment of outcomes included an evaluation of the changes in terms of ecological integrity and the supply of ecosystem services, using WET-Health and WET- EcoServices assessment techniques respectively, and vegetation composition. Improvements in hydrological and geomorphic integrity were recorded in both wetlands, resulting in improved ecosystem services delivery. However, investigation of vegetation composition using the Wetland Index Value and Floristic Quality Assessment Index showed that, seven years after rehabilitation, KiNamey's vegetation composition had improved, but Kruisfontein's vegetation was still largely dominated by pioneer species and appeared to be stable, but in a severely transformed state. The response of these wetlands has shown that sites for rehabilitation should be screened before work begins, and wetlands requiring intensive management of vegetation recovery should be assessed in terms of the objectives and the anticipated benefits of the project. The assessment of the outputs included an evaluation of structural integrity, survival and cost- effectiveness. Limited issues, mostly relating to deviations from the designs during construction, were identified with regards to the structural outputs at each of the wetlands. However, the spreader canals at both Killarney and Kruisfontein wetlands were not functioning as intended and concentrated flows from the spreader canals were evident in both wetlands. The use of spreader canals should therefore be carefully planned and implemented for future wetland rehabilitation projects. Consideration of ZAR per hectare equivalent re-instated/secured provided a useful initial means of determining the cost-effectiveness of the wetland rehabilitation. However, additional factors need to be considered, such as, the nature of the rehabilitation activities, the type and size of the problem being addressed, rehabilitation of priority wetlands, limitations imposed by funders, and risks that need to be addressed by the rehabilitation strategy. Furthermore, the evaluation of the Killarney and Kruisfontein wetlands highlighted the need to revise the Water Research Commission's Wetland Management Series, especially those documents or guidelines relating to rehabilitation planning (WET-RehabPlan), interventions (WET-RehabMethods), and monitoring and evaluation (WET-RehabEvaluate).
13

The hydrogeomorphology of the Featherstone Kloof Catchment

Ntakumba, Stanley Sixolile 29 May 2013 (has links)
Wetlands are an important part of the landscape as hydrogeomorphological ecosystems. Over the centuries their importance has not received relevant attention; instead they have been treated as wastelands impeding development for maximum economic benefits. Research evidence from different parts of the world has influenced the change of such negative perceptions to an extent that the issue of wetlands' rehabilitation/restoration, conservation and management is firmly on the global agenda and local agendas of various countries, as evidenced by the adoption of the Ramsar Convention in 1971, and the Working for Water and Working for Wetlands programmes of the South African government. The aim of this research was to investigate the hydrological and geomorphological functions of a headwater wetland located in the Featherstone Kloof Catchment near Grahamstown, South Africa. The research was based on the hypotheses that wetlands store sediments, attenuate floods, store water and prolong downstream flows. A literature survey was conducted to gauge the state of knowledge about wetlands, particularly their hydrogeomorphology. An attempt was made to locate the study area within the broad historical and spatial context using a number of methods, including the radiocarbon dating of wetland sediments, the review of relevant literature and the analysis of historical hydroclimatic data. The results revealed that the wetland has existed for approximately 2000 years - as the oldest radiocarbon date obtained was 1850±50 BP. An analysis of more than a century (+120 years) long Grahamstown rainfall series indicated a steady fluctuation of rainfall around the mean, with regular decada1 cycles of wet and dry spells. Years with more rain below average were more common than those with higher rainfall, and storms events were quite common in the III area over the period. The distribution of seasons in the area over a calendar year period was demonstrated through the use of evaporation data. An intensive monitoring of hydrological and geomorphological variables was carried out using a combination of methods. The topography of the instrumented site was determined using a Total Station from reference benchmarks. Hydrological measurements included a nest of forty-eight piezometers for water table monitoring, and streamflow gauges at the upstream and downstream limits of the study site. Soil stratigraphic analysis was carried out through field techniques and laboratory measurements. A survey of wetland sediments was carried out after the main floods events. Data generated were used to analyse relationships between various variables and their role on the functioning of the wetland. The water balance of the wetland was quantified. The results indicated that the wetland was able to perform the cited hydrogeomorphological functions to some extent. For example, one of the key findings of this research is that the wetland was important in sustaining base flows under normal circumstances. However, the wetland did little to attenuate large floods. The results also revealed some important questions that require further research, including the role played by extreme flood events in altering wetland characteristics, the contribution of each water balance component in the hydrological functioning of wetlands, and importance of quantifying sediment budgets of headwater wetlands. The study demonstrated the complex nature of the wetland hydro geomorphology and that certain questions about wetlands require direct field monitoring to be better understood. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
14

Developing and testing the congruency of selected biological indicators and an existing tool designed to assess wetland health in agricultural settings in the KZN Midlands

Kubheka, Patrick Skhumbuzo January 2018 (has links)
Despite the fact that wetlands have been understood to be important for a wide range of ecosystem services, wetlands continue to be degraded globally. There has been a growing need to develop biomonitoring tools that reflect the present ecological state of wetlands, but very few attempts have been made in South Africa to achieve this, and those that have attempted this have generally achieved limited success. This study was conducted to develop and test the congruency of four selected biological indicators (dragonflies, frogs, macroinveterbrates and plants) in relation to the assessment of present ecological state using an existing method in South Africa, "WET-Health". WET-Health assessments rely primarily on transformations to a wetland that result from human impacts in both the catchment and the wetland itself. Using the tool, a health score is obtained that is consistent with the Department of Water Affairs (DWA) current "present ecological state” as applied to river health assessment. The study was conducted in agricultural settings of the Midlands of KwaZulu-Natal based on 13 wetlands. The selected wetlands were scored using WET - Health and grouped in four different ecological condition classes (A, B, C and D). Physical characteristics (wetland area, mean depth), biological characteristics (species cover/abundance, presence and species richness), and chemical characteristics (ammonia, pH, sulphate, nitrogen and phosphate) were also recorded in the selected wetlands. Nineteen different species of dragonfly were recorded in this study. The study demonstrated that dragonflies are a promising bioindicator of wetland present ecological state as the dragonfly index was found to be closely correlated with WET- Health scores. Open water bodies within the selected wetlands were the focus of dragonfly sampling, as male dragonflies are territorial and they will patrol or be found around this habitat. Emergent vegetation dominated by sedges formed the focus of macroinvertebrate sampling in this study because greater numbers of macroinvertebrate families were found in this biotope in comparison to open water areas with no emergent vegetation. A total of 47 macroinvertebrate families were recorded in this study, but SASS5 scores based on macroinvetebrates showed no correlation with WET-Health scores. A total of 10 different frog species were recorded in this study. All the species were common frog species found in most parts of the country. Frog species richness and occurrence showed no correlation with WET- Health scores. A total of twenty samples of two meter radius were measured per wetland and sampled for plant species and estimation of cover-abundance of each species per sample. Over 50 different plant species were recorded in this study, and both species accumulation and species richness showed a degree of correlation with WET-Health scores. All the wetlands in class A had generally higher species accumulation rate and species richness compared to the other wetland classes. In addition to testing the congruency of four selected biological indicators with WET- Health, water quality was measured in all the wetlands. Wetlands in class A were associated with improved water quality as the water passes through the wetland. However, wetlands in class C and D did not show consistently improved water quality between the apex and the toe of these wetlands. In some cases the water quality deteriorated as it passed through wetlands in these two classes.
15

An assessment of water quality of the wetland downstream of Makhado oxidation and its potential effects on irrigation wters

Shibambu, C. S. January 2016 (has links)
MESC / Department of Hydrology and Water Resources / Wetlands are known of their pollution reduction characteristics due to their flat topography and dense vegetation which capture pollutants on the settling sediments. Three processes take place on the captured pollutants in the sediments, the physical, chemical and biological processes, which facilitate the removal of pollutants from the wetlands. This research was carried out in order to assess the Water Quality of wetland downstream of Makhado oxidation ponds and its potential effects on Irrigation Waters by determining the Physical-chemical parameters (pH, Dissolved Oxygen, temperature, electrical conductivity and turbidity); the nutrient levels (Nitrates, phosphates, nitrites, bromide) and heavy metals. The water samples were collected from the effluent discharge of Makhado oxidation ponds (upstream), the middle section of the wetland (midstream) and downstream of the wetland. The climate data for the study was also used assess the contribution to variation in the physical-chemical parameters during their passage through the wetland. The use of waters in the wetland by subsistence farmer’s was also assessed to determine their farmer’s perception on wastewater reuse, sustainability, water quality, health hazards and crop yield. At the discharge and midstream point, the physical parameters tested were found to be mostly outside the target water quality range of irrigation water set out by DWAF but are within the DWAF guidelines for discharge of wastewater. The exceptions were with total dissolved solids which were higher than 25 mg/l guideline value of the said standards. The anions were analysed by Ion chromatography and showed spatial variation in content and seasonality. The nutrients (nitrates, nitrites and phosphates) and chloride were higher than the DWAF guidelines for discharge of wastewater. The heavy metal content in the wetland was analysed by ICP-OES and varied throughout the wetland. The following metals were reduced during their passage in wetland and were within DWAF guidelines: zinc, lead, cadmium and total chromium. Iron and manganese were reduced during the drier season but were above the DWAF guideline values during the wet season. Also the metal contents in the wetland are out of the target water quality range of the same standards bringing forth the risks of toxicity in the wetland. The anion analysis also suggests that the wetland is becoming a nutrient rich environment bringing forth risks of eutrophication. Nitrite concentrations did not conform to the South African viii Water Guidelines on target water quality ranges for irrigation water. Farmers have expressed a positive opinion on wastewater use for irrigation since there are loads of nutrients. The presence of nutrients in wetland may contribute to development of harmful algal blooms.
16

Multi-stakeholder management of a wetland in the City of Tshwane: the case of Colbyn

Nemutamvuni, Kennedy 08 1900 (has links)
South Africa is ranked as one of the most mega-biodiverse countries in the world. But as the country faces poverty, unemployment and income inequalities, it is a mammoth task to develop, sustainably use and appreciate this natural capital. Thus, South Africa must find ways to ensure a balance between conservation of biodiversity and the achievement of socio- economic development. But when land is set aside for conservation, in most cases, local communities are on the receiving end of the decision making, with little to no opportunity to be involved. The Colbyn Valley Wetland is different, however. The site provides invaluable ecosystem goods and services to the local residents, as well as being an integral part of the Hartbeesspruit catchment and Roodeplaat dam. It has a history of sustained attempts to convert the site into housing estates, shopping centres or car parking. These attempts have met with unrelenting resistance by the local residents. Contrary to the experiences of other communities in South Africa, Colbyn Valley residents have elected to work together with other stakeholders to ensure the protection of this site. This study documents the processes that the residents undertook to protect the wetland. In this regard, local authorities can learn how to leverage stakeholder engagement to protect other sites. Importantly, the study found that the various stakeholders involved in the preservation of the Colbyn Valley Wetland were driven by different but interwoven interests. Thus, different interests need to be taken into consideration before protected areas adjacent to communities can be proclaimed. For example, the primary stakeholders - local residents who initiated the call to protect the Colbyn Valley Wetland – hold strong beliefs that the wetland must be preserved for ecosystem goods and services that it provides. Secondary stakeholders – the provincial government departments responsible for the management and protection of ecosystems – only acted when pressured by the local residents, despite their legal obligations to protect the site (as it carries so much value to the water provision of the city). The tertiary stakeholders – various voluntary institutions and people – elected to support the conservation effort due to the manner in which the local residents organised themselves and developed a vision for the site. / Environmental Sciences / M. Sc. (Environmental Science)
17

The impact of riparian alien plant removal on aquatic invertebrate communities in the upper reaches of Luvuvhu River Catchment, Limpopo Province

Modiba, Refilwe Victor 05 1900 (has links)
MSc (Zoology) / Department of Zoology / See the attached abstract below
18

Population biology and ecology of Vachellia karroo (Hayne) Banfi and Galasso in the Nylsvley Nature Reserve, Limpopo Province, South Africa

Madilonga, Mpho Given 18 September 2017 (has links)
MSc (Botany) / Department of Botany / Plant populations are determined by many elements that impose demographic filters. Following disturbance, in African savanna woodland trees regenerate both sexually and vegetatively. Vachellia karroo (Hayne) Banfi and Galasso, family Fabaceae and sub family Mimosideae, commonly known as “sweet thorn” or “soetdoring” (Afrikaans), is a leguminous shrub common throughout Southern Africa. Its distribution range is from the Southwestern Cape northwards into Namibia, Angola, Botswana, Zambia and Zimbabwe. It is a pioneer species and has the ability to encroach rapidly into grassland grazing areas. Therefore, V. karroo is considered the most important woody invader of grasslands in South Africa. This study aimed at investigating the population biology and ecology of V. karroo in the clay waterlogged site of the Nylsvley Nature Reserve. Plant height, stem circumference, canopy cover, distance between individuals were measured and disturbance levels on individuals of V. karroo were estimated during sampling. The results showed that the population of V. karroo display an adequate growth curve thus implying that the population of V. karroo in the Nylsvley Nature Reserve is healthy and viable. More mature healthy individuals were found in September and December, than during June and July; this is obviously because early summer season, and in September most of the savanna plant species were starting to actively recover from the winter dry season. This is confirmation enough that the population of V. karroo is expanding in the clay waterlogged areas of Nylsvley Nature Reserve.
19

An investigation of seasonal disturbance intensity on wetland grass belts of Nysvley Nature Reserve

Gelebe, Vhuhwavho 17 May 2019 (has links)
MSc (Botany) / Department of Botany / The use of disturbance in the management of Savanna is a common rangeland practice in South Africa. A two-season trial was established in June 2016 and December 2016 to evaluate the effects of disturbance of different intensities on wetland belts in the Nylsvley Nature Reserve. The disturbances were in three different belts of different grass types at different intensities. The experimental treatments consisted of two different intensities, namely; high (H) and low (L). The Cyperus amabilis belt was regarded as site 1, the Sporobolus africanus as site 2, and the Themeda triandra as site 3. Seventeen kites were contracted in each belt, two times 1 m × 1 m at high and low intensity, followed by two times 2 m × 2 m one at high intensity. The results showed that disturbance affects the topsoil by removing the soil which is rich in nutrients producing pioneer species for the first few months and then original species were seen inhibiting again. / NRF
20

Review of local institutional arrangement for Zone 3 community wetland in Sebokeng, Gauteng, South Africa

Siyaya, Jabulani Sebenzani January 2015 (has links)
The study focused on the role of the local community in the management of wetland. The study was triggered by the lack of participation of the local community in the management of the wetland. It is important to note that wetlands perform a number of ecosystem services, some of which are well recognised, others less so, and are internationally recognised as being one of the most important ecosystems for the conservation of biodiversity. South Africa is a signatory to the international obligations, which makes it a legal responsibility to make sure that wetlands are managed appropriately. It is therefore important for these natural resources to be managed appropriately. Information for generating data was obtained through the assessment of the wetland health and from the investigation of the management of the local community. In order to achieve the objectives of the study, qualitative method was used to gather the necessary data. The findings indicate that the current state of the wetland is severely modified, which means large loss of natural habitat, biota and basic ecosystem functions has occurred. The results also indicate that the community is ill-equipped to manage the resource appropriately. The findings therefore imply that immediate management interventions must be developed to improve the health of the wetland. In improving the state of the wetland, the study recommends, amongst others, that mitigation measures aimed at improving the wetland health and participation of wetland users be promoted. An establishment of a community-driven and multi-stakeholder intervention mechanism to help the community manage and utilise the wetland properly is also recommended. The study concludes by indicating that the community must comply with the environmental legislation and takes a lead in the management of the wetland, for the aim of restoring the functionality and integrity of the wetland. / Environmental Sciences / M. Sc. (Environmental Management)

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