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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.
121

Mesozooplankton dynamics in a biogeographical transition zone estuary

Deyzel, (Shaun) Herklaas Phillipus January 2012 (has links)
This thesis presents the first intensive community-level investigation of the mesozooplankton from a biogeographical transition zone estuary. The Mgazana Estuary is located along a rural, semi-undeveloped part of South Africa’s east coast, believed to represent a transition zone between the subtropical and warm-temperate biogeographical zones. The research represented in this thesis involves data collected over a five year period between 2002 and 2006, with additional data collection made in 2008. The study focussed on five areas of investigation, the first of which investigated the physico-chemical dynamics of the Mgazana Estuary. The Mgazana Estuary exhibited marked vertical, horizontal and regional structures in the hydrological environment. Prominent vertical and horizontal stratification characterised summer months. A substantial turbidity front was observed in the lower estuary during summer and winter. The upper estuary was marked by considerable variation in multiple variables but especially salinity. These structures appeared to have shifted in position over the horizontal plane, which was attributed to variation in freshwater flow. The second study focused on the spatial dynamics of mesozooplankton in the Mgazana Estuary. The zooplankton was rich and in terms of composition typical of mangrove systems. The Copepoda were dominant, numerically and in terms of taxonomic representation. Calanoids Acartiella natalensis and Pseudodiaptomus hessei characterised middle and upper reaches in summer and mostly upper reaches in winter. On community level, a highly structured assemblage arrangement was observed during summer and winter months. These trends were further scrutinised under the theoretical framework of ecological boundaries. In so doing, an agreeable spatial association emerged between specific assemblages and their environments. These trends were concluded to reflect ecoclinal as well as ecotonal properties, the latter describing interactions over narrow spatial bands of marked changes in turbidity. The third study investigated flooding events as short-lived extreme meteorological events and the influence on zooplankton. Within this regard, second-stage multivariate statistics was used to assess year-to-year variability in assemblage structures on whole-system and regional scales. The impact of two major flooding events that flushed the estuary some days prior to sampling could clearly be elucidated. Flooding emerged as a significant source of inter-annual variability in the zooplankton of the Mgazana Estuary. Second-stage multivariate analysis proved to be an effective analytical strategy for investigating inter-annual variability in species assemblage structures. Results from the preceding study prompted a detailed investigation into the spatio-temporal dynamics of Acartiella natalensis, the most important zooplankton species of the system aimed at elucidating flood responses. Acartiella natalensis showed indication of temporal arrest in association with flooding events in a similar fashion as is observed in seasonal variation trends in estuaries towards its geographical distribution limit south of the study area. It was concluded that A. natalensis was severely affected by floods and the possibility exist for entrainment of entire populations from the estuary during flooding events. The final study tested the hypothesis of post-flood propagation from a resting egg bank in the sediments of the Mgazana Estuary. Preliminary data revealed that numerous eggs were present in the sediments. Nauplii hatched from eggs under laboratory conditions were identified as belonging to the family Acartiidae. The preliminary mode of diapause is presented as a schematic model, emphasising the role of freshwater flow and specific environmental variables. This was the first discovery of resting eggs from a subtropical estuary from South Africa. It is hoped that the findings of this study would give rise to new research initiatives investigating the importance of resting stages in estuarine and coastal Copepoda species and the role such reproductive strategies may play in estuarine functioning.
122

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.
123

Aspects of the revegetation of mountain fynbos vegetation of the south western Cape, South Africa

Romoff, Natalie January 1989 (has links)
The revegetation of severely, disturbed areas using indigenous vegetation forms the topic of this thesis. Mountain Fynbos was chosen for the study because of its importance as a unique vegetation-type worthy of conservation. Unfortunately, this vegetation faces long-term threats associated with escalating development pressures, which include the demand for improved infrastructures. These factors are discussed and a process is developed for using indigenous vegetation to revegetate severely disturbed areas. This use of indigenous vegetation represents a significant and innovative move away from the traditional use of commercially available grasses in South Africa. Fynbos is adapted to periodic droughts and nutrient poor soils and as such has practical advantages over artificial plant covers in terms of its low maintenance requirements for long term establishment. Theoretical perspectives of disturbance and succession are contrasted with the requirements for revegetation as observed in the field.
124

Aard en omvang van omgewings- en groenpolitiek in Suid-Afrika : met spesiale verwysing na die rol van belangegroepe in die Wes-Kaap

Vollgraaff, Heléne, 1966- 11 1900 (has links)
Environmental and green politics came into prominance during the last two decades. These two concepts, as well as environmentalism and ecologism are defined in this study and placed within the context of the political system. The emphasis is on green politics and ecologism. The global green movement is analysed according to policy, organisational structures and pattern of development. The South African environmental and green movements are described in the latter part of the study. It is shown that South Africa has a long history of environmentalism. The South African green movement is compared with the global green movement after which it is placed within the context of the South African political system. Green politics in South Africa seems to resemble the early stages of the development of the European movement and the concept of social justice is emphasised. Selected Western Cape groups are discussed according to information gathered by means of a questionnaire. / Political Science / M.A. (Political Science)
125

The interaction between vegetation and near-surface water in a wetland system, Stellenbosch, South Africa

Kareko, John K.(John Kariuki) 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Understanding the responses of individual plant communities to variations in near-surface water levels and to water quality is a step towards determining the critical or important factors applicable to a Rapid Wetland Assessment System. This thesis describes and discusses factors associated with wetland plant communities, with an attempt to predict changes in a wetland system. This study was initiated with a primary aim of establishing the relationship between plant communities and the variation in near-surface water levels in areas occupied by various plant communities in the Middelvlei wetland system at Stellenbosch. A second aim was to assess whether water quality had an influence on the plant communities. Seven plant communities are identified and described from this particular wetland system using standard Braun-Blanquet techniques (Typha capensis Reedswamp; Cyperus textilis Sedgeland; Pennisetum macrourum Grassland; Juncus effusus Sedgeland; Cyperus longus Sedgeland; Cliffortia strobilifera Shrubland and Populus canescens Forest). The Typha capensis Reedswamp community is found in the wettest parts of the wetlands, with a fluctuation in water table from 0.10 m above surface during the wet season to 0.43 m below surface during the dry season. The Populus canescens Forest is actively invading the wetland replacing the wetland species by modifying the wetland hydrological condition. Water samples from 35 wells, collected on a monthly basis over 11 months, are used to assess sodium, magnesium, potassium, calcium, nitrate and phosphate, pH, redoxs potencial and dissolved oxygen levels in each community, over four seasons. Both multivariate analysis (ANOVA) and regression tree analysis (CART) are applied to evaluate differences between communities or groups of plant communities on a seasonal basis. Direct gradient analysis (CCA) is used to determine the relationship between plant communities and environmental variable gradients. A wide variation in water quality condition between plant communities is present. The Typha capensis Reedswamp community is associated with low nutrient levels (phosphates and nitrates) in all seasons. The Cyperus textilis Sedgeland is associated with low levels of nitrates and high phosphate levels. The Juncus effusus Sedgeland displays the highest phosphate concentration, occurring in summer, while low nitrate levels occur in this community during all the seasons. Dissolved oxygen in the near-surface water in this wetland is at very low concentrations, and has no significant difference between communities. It plays no major role in determining the occurrence and distribution of the plant communities. Most of the water chemical constituents measured in this study are the result of multiple complex relationships, with constituent variations occurring differently between communities. A remarkable seasonal distinction in the chemical constituents in different communities is present. Despite the complex nature of the relationships between plant communities and environmental factors, the low species diversity levels through the tendency for single species dominance and the strong association of these communities with particular environmental variables, the combination of these factors all add value to the use of wetland vegetation as a good tool to indicate wetland condition. An effort to understand wetland plant communities in relation to determining environmental factors would promote the use of plant communities as user-friendly tools for wetland monitoring and assessment. / AFRIKAANSE OPSOMMING: Om die reaksies van plantgemeenskappe teenoor variasies in naby-oppervlakte watervlakke te verstaan, is die eerste krities-belangrike faktor die ontwikkeling van ‘n sisteem om vleilande vinnig te assesseer. Hierdie studie se basiese mikpunt is om verwantskappe te soek tussen plantgemeenskappe in die Middelvlei Vleilandsisteem en wisseling in naby-oppervlak watervlakke. ‘n Sekondêre doel is om te bepaal of daar enige korrelasie is tussen waterkwaliteit en die plantgemeenskappe teenwoordig in die vleiland. Sewe plantgemeenskappe is in hierdie vleilandsisteem geïdentifiseer en beskryf deur gebruik te maak van standaard Braun-Blanquet tegnieke, naamlik die Typha capensis Rietmoeras; Cyperus textilis Biesieveld; Pennisetum macrourum Grasveld; Juncus effusus Biesieveld; Cyperus longus Biesieveld; Cliffortia strobilifera Struikveld en ‘n Populus canescens Woud. Die Typha capensis Rietmoeras kom in die natste dele van die vleilande voor, met vrywater wisselling vanaf 0.10 m bo grondoppervlakte, tydens die nat-seisoen, tot 0.43 m onder grondoppervlakte tydens die droë seisoen. Die Populus canescens Woud het die grootste wisseling in watervlak vanaf die grondoppervlakte tot ten minste ‘n diepte van 1.0 m gehad. Dit blyk dat die Populus canescens Woud besig is om die vleigemeenskappe aktief binne te dring deur die vleiland uit te droog. Water is maandeliks, oor 11 maande, uit 35 geperforeerde plastiek pype, sogenaamde ‘putte’ onttrek, om natrium, magnesium, kalium, kalsium, nitrate en fosfate, pH, redokspotensiaal en opgeloste suurstof vlakke se seisoenale wisseling te bepaal. Beide veelvuldige analise (ANOVA) en regressie-analises (CART) is bereken om enige betekenisvolle verskille tussen plantgemeenskappe te bepaal. Direkte Gradiëntanalise (CCA) is gebruik om die verwantskap tussen plantgemeenskappe en gradiënte van omgewingsveranderlikes te bepaal. Groot variasies in waterkwaliteit tussen plantgemeenskappe is waargeneem. Die Typha capensis Rietmoeras-gemeenskap is geassosieer met lae voedingstofvlakke (veral van fosfate en nitrate) in alle seisoene. Die Cyperus textilis Biesieveld-gemeenskap is geassosieer met lae nitraat- en hoë fosfaatvlakke. Die Juncus effusus Biesieveldgemeenskap vertoon die hoogste fosfaatvlakke, tydens die die somermaande, terwyl die nitraatvlakke deur al die seisoene ook laag bly. Opgeloste suurstof in die naby-oppervlakte water in die vleilandsisteem het deurgaans ‘n lae konsentrasie vertoon met geen betekenisvolle verskille tussen gemeenskappe nie. Dit speel dus geen belangrike rol in die voorkoms of verspreiding van die plantgemeenskappe nie Die meeste van hierdie faktore, gemeet om die waterkwaliteit te bepaal, het veelvoudige, komplekse verhoudingsverskille, gebaseer veral op konsentrasieverskille, tussen die gemeenskappe. Ten spyte van die komplekse verwantskap tussen die plantgemeenskappe en omgewingsfaktore, is die spesierykheid laag en kom die neiging tot eensoortigedominansie algemeen in die vleiland-plantgemeenskappe voor. Die sterk assosiasie tussen die plantgemeenskappe en bepaalde omgewingsveranderlikes voeg aansienlike waarde daaraan toe om vleilandplantegroei te gebruik as indikator van vleilandtoestand. ‘n Poging om die verwantskappe tussen vleiland-plantgemeenskappe en omgewingsveranderlikes algemeen te bepaal, sal die gebruikersvriendelike nut van vleiland-plantgemeenskappe vir vleilandmonitering en assessering duidelik uitwys.
126

Assessment of fish as bio-indicators of river health in rivers of the southwestern Cape

Hayes, Johan Barnard 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: In this study, the Fish Assemblage Integrity Index (FAll) was applied on three rivers within the southwestern Cape. This index uses fish as indicators of biological aquatic integrity and is based on indigenous species expected to be present in biological fish habitats. Fish integrity classes were calculated for each of the sites in the three rivers studied. Sites 2 and 4 within the Lourens River were rated as Class C, whereas sites 1 and 3 were rated as Class F and Class D respectively. Sites 1, 2 and 4 within the Palmiet River were rated Class F, whereas sites 3 and 5 were rated as Class E and Class D respectively. Site 1 within the Hout Bay River was rated as a Class F site, in addition to sites 2 and 3 been rated as Class A. It is however, suggested that the FAll needs to be adjusted to accommodate the general low species richness experienced in the southwestern Cape. In addition to the FAll been applied, the effects of long-term exposure to subtle water quality changes associated with human activities, specifically potential estrogenic compounds in fish from the Lourens River were also investigated. The production of the yolk precursor lipoprotein complex, vitellogenin (Vtg) produced in the liver under estrogen control was employed as biomarker for environmental estrogen exposure. Male fish from the Lourens River were studied using SDS-PAGE gel electrophoresis. Results indicated that 60% of male fish showed the presence of Vtg in their plasma. Abnormal gonad morphology in male and female fish were also assessed using standard histological procedures. Results from this study indicated no observed abnormalities in either male or female gonads. The immediate presence of endocrine disrupters with estrogen activity was investigated by screening water samples from the Lourens, Palmiet and Hout Bay Rivers for estrogen activity. Results indicated that none of the samples appeared to be cytotoxic. In addition, estrogen activity of water samples was also investigated by in vitro culturing of water samples with frog, Xenopus laevis, liver slices. Results indicated that none of the water samples from the three rivers studied indicated estrogenic activity. Although cytotoxicity and estrogen activity results were negative, the production of Vtg in male fish suggests further research regarding the presence of estrogenic substances in these rivers. / AFRIKAANSE OPSOMMING: In die huidige studie is die 'Fish Assemblage Integrity Index' (FAIl) toegepas op drie rivere in die suidwes Kaap. Hierdie indeks gebruik visse as bioindikatore van biologies akwatiese integriteit en is gebasseer op die inheemse visspesies wat verwag word in biologiese vishabitatte. Integriteitsklasse is bepaal vir elke studieterrein in die drie rivere wat ondersoek is. 'n Klas C is bepaal vir studieterreine 2 en 4 in die Lourensrivier. Klas F en Klas D is bepaal vir studieterreine 1 en 3 in die rivier onderskeidelik. 'n Klas F is bepaal vir studieterreine 1, 2 en 4 en Klas E en Klas D bepaal vir studieterreine 3 en 5 in die Palmietrivier onderskeidelik. 'n Klas F is bepaal vir studieterrein 1 in die Houtbaairivier waar 'n Klas A bepaal is vir studieterreine 2 en 3. Dit word egter voorgestel dat die FAII aangepas moet word om die algemene lae spesierykheid wat ervaar word in die suidwes Kaap te akkomodeer. Die reaksie van visse, afkomstig van die Lourensrivier, op die langtermyn blootstelling aan estrogeniese stowwe is ook bestudeer. Spesifieke reaksies van endokriene versteuring, soos vitellogeen (Vtg) produksie in manlike visse is ondersoek deur middel van SDS-PAGE gel elektroforese. Resultate toon dat in 60% van die manlike visse Vtg in die plasma teenwoordig was. 'n Ondersoek na abnormale gonade morfologie in manlike en vroulike visse van die Lourensrivier is deur standard histologiese prosedures gedoen. Resultate hiervan dui op geen sigbare abnormaliteite in die gonades nie. Die onmiddelike teenwoordigheid van endokriene versteurders is bestudeer deur die sitotoksisiteit van watermonsters afkomstig van die Lourens, Palmiet en Houtbaai riviere te bepaal. Resultate dui aan dat geen monsters sitotoksies was nie. Die estrogeenaktiwiteit van die watermonsters is ook ondersoek deur van in vitro kulture van watermonsters saam met padda, Xenopus leavis, lewersnitte gebruik te maak. Geen estrogeniese aktiwiteit is in die watermonsters gevind nie. Al is die sitotoksisiteit en estrogeenaktiwiteit resultate negatief, dui die produksie van Vtg in manlike visse op die noodsaaklikheid van verdere navorsing ten opsigte van die teenwoordigheid van estrogeniese stowwe in drie riviere.
127

Opportunity and connectivity : selecting land managers for involvement in a conservation corridor linking two protected areas in the Langkloof Valley, South Africa

McClure, Alice January 2011 (has links)
The Eden To Addo Corridor Initiative aims to connect formally protected areas in a conservation corridor from the coastal area of the Eden District near Plettenberg Bay, Western Cape, South Africa to the Addo National Elephant Park, Eastern Cape, South Africa. The corridor will incorporate government and privately owned land, and will be an attempt to maintain ecological processes at a range of spatial and temporal scales. The Langkloof Valley lies between the Baviaanskloof World Heritage Area and the Tstitsikamma National Park; two formally protected areas that will be incorporated into the Eden To Addo Corridor. Spatial prioritization analyses allow conservation planners to select areas that should be targeted for conservation action based on a range of criteria. Historically, ecological criteria have been included mostly alone in spatial prioritization. Recently, the idea of ‘conservation opportunity’ has emerged in the field of conservation planning; the notion suggests that a range of different types of data should be included in processes to spatially prioritise for conservation. By including those data defined as ‘human’ and ‘social’ data into prioritising activities, the feasibility of conservation plans can be accounted for, but historically conservation planners have failed to do so. I conducted a literature review that demonstrated that although the importance of human and social data are acknowledged in the conservation planning literature, these data that define opportunity are rarely actually included in spatial prioritisation analyses. I then carried out a social assessment that allowed me to define the social and human context of our study area and, specifically, what stewardship instruments land managers in the Langkloof would be prepared to engage. We found that land managers were generally willing to engage, but lacked the financial capacity to adopt conservation methods. Using a subset of the social and human data that were collected in the social assessment, I trialled a new Decision Support Software to fuse those data with ecological data in a novel attempt to identify priority areas for conservation action based on ecological integrity and feasibility. We also scheduled (ranked) land managers to approach for conservation action with a focus on local champions and clusters of land managers displaying strong conservation characteristics. Two corridors were identified; a major corridor in the western region of the valley and a secondary corridor closer to the middle. The members of the Initiative have been briefed on the outcomes, which provided them an opportunity to provide feedback; it is hoped that the framework of this study can be used for planning future connections. The Eden To Addo Corridor Initiative sent out a stewardship extension officer in February 2011 to approach those land managers areas that were identified. This planning exercise is a good demonstration of how, by collaborating effectively, academic conservation planners can contribute to supporting decision making by organizations that are implementing conservation action.
128

Evaluating people-environment relationships : developing appropriate research methodologies for sustainable management and rehabilitation of riverine areas by communities in the Kat River Valley, Eastern Cape Province, South Africa

Motteux, Nicole January 2003 (has links)
International evidence clearly indicates that water shortages and the enhanced value attached to water and aquatic ecosystems are key concerns faced by many countries. International experience, since the mid-1980s, has emphasised the importance of addressing political, social, environmental and economic issues through active stakeholder participation in riverine and water resource management. These trends and issues are relevant to South Africa, where integrated water resource management (IWRM) is now a cornerstone of water resource policy and the National Water Act (NWA). Apartheid excluded communities in former homelands (racial reserves) from participation in IWRM. The research presented in this thesis was based on the search for philosophies and methods to involve the rural, former homeland people of the Kat River Valley in South Africa in IWRM. Post-modern, humanist and some logical positivist geographical philosophies were used during the research. This research applied Participatory Rural Appraisal (PRA) philosophy and methods and was influenced by the seminal work of Paolo Freire (1972). In addition, the use of innovative methods for engagement of the oppressed, using theatre methods developed by Augusto Boal (1995, 2000) was explored to add value to PRA. In addition, the application of Action Research ensured that community participants were actively involved in the research being conducted for this thesis. The applied research in the Kat River Valley in South Africa evolved through three key phases. In Phase One quantifiable data on the Kat River Valley and its residents was sought. This investigation did not empower the resident communities of Fairbairn and Hertzog – a lesson that influenced the move to more participatory methods in subsequent phases of the research. Lessons learned from using surveys encouraged exploration of participatory methods to enable participants to become “co-learners”. Phase Two of the research commenced with a series of feedback meetings, in which participants recognised that they faced an environmental crisis. Through a series of participatory workshops, residents came to acknowledge and affirm their environmental knowledge. Residents then committed themselves to gaining a deeper understanding of their environment and their lives. My role changed from that of a researcher to a facilitator. Phase Three of the research and the shift to Action Research commenced after local residents identified the need to personally take charge of their environmental challenges in the Kat River Valley and recognised the need to collaborate at a catchment scale for effective IWRM. This eventually led to the formation of a Water User Association and Catchment Forum. The key theoretical contribution of the thesis relates to the identified relationship between the development orientation and ecological paradigm, and an assessment of the impact this has on the inputs, processes, outputs and outcomes of IWRM. This theoretical contribution is equally valid in other countries, where the tradeoffs are essentially the same, but the framework for making the choices is different because of varying socio-economic and biophysical circumstances
129

Ecological characterisation and effects of fire and grazing on Cyrtanthus nutans (R.A.Dyer) in North-Western Kwazulu-Natal, South Africa

Ruddle, Lynne Michelle 05 1900 (has links)
Cyrtanthus nutans (RA Dyer) is a KwaZulu-Natal Province near-endemic species, classified as vulnerable in South Africa (IUCN Red Data categories). Literature references suggest that no recent ecological research has been conducted on Cyrtanthus nutans. Last assessed in 2007, the current study determined the demographics and the abiotic and biotic factors that influenced the distribution and range of Cyrtanthus nutans. Key determinants influencing the autecology, distribution and population dynamics of Cyrtanthus nutans were investigated. Anthropological factors influencing the decline of populations were addressed. Two investigations were undertaken for the current study on Cyrtanthus nutans in Dundee in North-western KwaZulu-Natal, South Africa namely a survey to determine the population dynamics and autecology of the species and the effect key determinants have on the recruitment and survival. Sites of occurrence and the ecological and anthropological factors that influence the existence of plants were documented. Experimental plots were conducted to determine the influence of climatological factors, fire and defoliation on the emergence and survival of Cyrtanthus nutans plants. A preference was found for soils with high nitrogen and organic carbon, low phosphorus and acidity levels situated on slopes of < 10% on mid to lower terrain slopes within an altitude range of between 1 100 and 1 300 m (a.m.s.l.) in the Sour Sandveld and Moist Tall Grassveld Bioresource Groups. The influence that climatological factors, fire and defoliation had on the emergence and seed recruitment of Cyrtanthus nutans were determined through a small plot experiment in the Dundee area. Mean relative humidity (%) and mean rainfall two weeks before emergence in conjunction with treatments were highly significant (P<0.001). Burning treatments B (fire inclusion and defoliation inclusion) and BC (fire inclusion and defoliation exclusion) were more highly significant on the emergence of Cyrtanthus nutans plants than any other treatments. ii | P a g e Increasing fragmentation of thriving populations of Cyrtanthus nutans populations is occurring through landuse change, mismanagement of veld and non-compliance of legislation. Continued monitoring and awareness is essential in the survival of this species. / Environmental Sciences / M. Sc. (Environmental Sciences)
130

Aard en omvang van omgewings- en groenpolitiek in Suid-Afrika : met spesiale verwysing na die rol van belangegroepe in die Wes-Kaap

Vollgraaff, Heléne, 1966- 11 1900 (has links)
Environmental and green politics came into prominance during the last two decades. These two concepts, as well as environmentalism and ecologism are defined in this study and placed within the context of the political system. The emphasis is on green politics and ecologism. The global green movement is analysed according to policy, organisational structures and pattern of development. The South African environmental and green movements are described in the latter part of the study. It is shown that South Africa has a long history of environmentalism. The South African green movement is compared with the global green movement after which it is placed within the context of the South African political system. Green politics in South Africa seems to resemble the early stages of the development of the European movement and the concept of social justice is emphasised. Selected Western Cape groups are discussed according to information gathered by means of a questionnaire. / Political Science / M.A. (Political Science)

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