To see the other types of publications on this topic, follow the link: Rivers – Environmental aspects – Botswana.

Dissertations / Theses on the topic 'Rivers – Environmental aspects – Botswana'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Rivers – Environmental aspects – Botswana.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Msukwa, Chimwemwe Kanyamana. "Strategic interests in transboundary river cooperation in Southern Africa – the case of the Okavango." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5239.

Full text
Abstract:
Thesis (MA (Political Science. International Studies))--University of Stellenbosch, 2010.
Bibliography
ENGLISH ABSTRACT: Water is life. Its availability and quality directly relates to what is possible in agriculture as well as human health. In Southern Africa, water issues have become an important political agenda as a result of the droughts that the region has been experiencing. The Southern Africa Development Community (SADC), in its water protocol advises its member states to set up river basin organisations to manage transboundary rivers in Southern Africa. The aim is to encourage the sustainable use of international rivers. Sharing international rivers has proven to be a very difficult issue as shown by the voting patterns on the UN Convention on the Law of Non Navigational Uses of Transboundary Rivers and the subsequent failure of entry into force of this convention. While strategic interests on the global levels manifest themselves in voting patterns in forums like the UN Assembly, the situation is trickier at the regional level. These strategic interests are ever present as a result of states’ need for recognition of their sovereignty and the inability of states to accept any hierarchical enforcement. This study investigates the impact of these interests at the basin level on the structure of cooperation. With the use of a case study, namely the Okavango River Basin Commission, and guided by regime theory, the study looks at the process of regime formation and maintenance in the basin. It concludes that states use cooperative arrangements (international water cooperation regimes) as tools for the strategic protection of their sovereignty.
AFRIKAANSE OPSOMMING: Water is lewe. Die beskikbaarheid en kwaliteit het direk te betrekking op wat moontlik toeneemed is in landbou so wel as menslike gesondheid. Water as ʼn noodsaaklike bron in suider-Afrika word meer en meer beskou as ʼn belangrike kwessie op die politieke agenda as gevolg van droogte wat in die streek ondervind word. ʼn Hoë vlak van belangrikheid word aan die bestuur van water binne die streek geheg. Die SAOG (Die Suider – Afrikaanse Ontwikkelings gemeenskap), het in sy water protokol aan sy lid state beveel om rivier kom organisasies te stig om beheer uit te oefen oor riviere in Suider- Afrika wat oor grense heen vloei. Die doel is om lidstate aan te moedig om die volhoubare gebruik van internasionale riviere te bevorder . Die vedeling van internasionale riviere is ‘n komplekse kwessie soos wat VN stempatrone aandui ten opsigte van die Wet op die Verbod teen Navigasie op Oorgrensende Riviere en die daaropvolgende versuim van die inwerkingtreding van die Konvensie aandui. As gevolg van state se behoefte vir erkenning van hul soewereiniteit en hul strategiese belange bly die deel van rivierkomme ‘n moeilike internasionale probleem. Hierdie studie ondersoek die impak van die bogenoemde belange op die kom vlak op die struktuur van samewerking. Met die gebruik van ʼn gevallestudie, naamlik die Okovango Rivier Kom Kommissie, en aan die hand van regime teorie, ondersoek die studie die proses van regime formasie asook die problematiek rondom die instandhouding van die Komissie. Die gevolgtrekking is dat state koöperatiewe reëlings (internasionale water samewerking regimes) as instrumente vir die beskerming van hul strategiese soewereiniteit en eie belange gebruik.
APA, Harvard, Vancouver, ISO, and other styles
2

Lesley, Michael Patrick. "The fluxes and fates of arsenic, selenium, and antimony from coal fired power plants to rivers." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180307/unrestricted/lesley%5fmichael%5fp%5f200312%5fms.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Mengwe, Moses Seargent. "Towards social impact assessment of copper-nickel mining in Botswana." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1443.

Full text
Abstract:
This research study is more of an initiative towards Social Impact Assessment of copper-nickel mining in Botswana. The specific objectives of the study were centred on the assessment of the social impacts of copper-nickel mining in Botswana from the initial mining stage of exploration, surveying and mine site development to mine closure. The study was carried out under the broad hypotheses that mining influences population movement that impact on areas of mining; mining activities have both economic benefits and deleterious social impacts on the local communities found in the areas where mining is taking place; and mine closure has far reaching socio-economic, investment and developmental implications over and above the obvious interests of project owners. To achieve the broad aim as summarised above, the research study used a multi-disciplinary methodology and approach that required several kinds of expertise and sources of information. Hence it used both primary and secondary sources centred on interactive informative interviews, site visits and observations, questionnaires, census data records, mining companies’ publications, published textbooks and journal articles. The research study comprised of three different mines operated by three different mining companies in three varied socio-cultural and ethnic regions of Botswana. First was a detailed Social Impact Assessment of the initial phase of exploration, surveying and mine site development represented by Mowana mine project operated by African Copper in the rural areas of Dugwi and Mosetse. This case study yielded results showing that the social impacts of mining in the area are diverse and extensive. The findings suggest that the impacts relate not only to the possible economic benefits of foreign exchange, employment, the optimal use of available mineral resources and the possible development of Dugwi and Mosetse villages, but extends to the deleterious social impacts. The results also indicated that the social impacts have just begun in the two communities. Hence they point towards a possible disruption within the socio-cultural system of the local people if serious mitigation measures are not put in place; thus suggesting that the early stages of exploration and mine site development results in the most conflict between the mine and the local people. Second was a comprehensive Social Impact Assessment of Tati-Nickel Phoenix mining project in the peri-urban areas of Matshelagabedi and Matsiloje areas representing the mining stage of mine production and expansion. The results from this case study suggest that during vi mine production and expansion, many people were relocated. However, the overriding impression gained from the case study was Tati-Nickel Mining Company’s elaborate corporate policies that suggested good corporate governance and best practices that promote sustainable development. A notable milestone on good corporate governance and best practice that the other two case studies (mining company) could benchmark on is Tati-Nickel’s corporate social responsibility programme that has been designed to ensure that the communities within a fifty kilometre mine radius benefit from the mine. The results from the case study also distinguished the mining stage of production and expansion from the other two because it is associated with the deep entrenchment of the social impacts into the communities near to mining areas. Third was a detailed Social Impact Assessment on Bamangwato Concession Limited mine in the industrial town of Selebi-Phikwe. The case study represented the stage of mine closure. Through the findings of this case study, it became apparent that the economic dependence of Selebi-Phikwe on mining has seen the town developing into a mining town, increasing its vulnerability at mine closure. The results from the case study further suggest that mine closure will degrade the socio-economic sector of the town with ever far reaching socio-economic implications as many people lose their gainful employment, hence suggesting that a possible complete mine closure will be the most traumatic phase leading to major social conflict within the area. Thus the results suggest that at mine closure, the deleterious social impacts will overspill to other areas in Botswana with disastrous effects for the economy of the country. The results yielded through this study established in clear and passionate language that copper-nickel mining in Botswana influences population movements that lead to positive and negative impacts on the communities found in mining areas. Another major finding of the study is that copper-nickel mining activities have both economic benefits and deleterious social impacts on the local communities, hence the recommendation that the copper-nickel mining companies should embrace the concept of sustainable mining for sustainable development to avoid most of the negative impacts of their operations on the local communities.
APA, Harvard, Vancouver, ISO, and other styles
4

Keatimilwe, Kagiso P. "Consequences of modernisation in Botswana : lessons and alternatives for the livestock sector." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30010.

Full text
Abstract:
The purpose of this thesis is to analyse the effects of post-independence modernisation policies within the cattle sector in Botswana and to suggest alternative ways of dealing with the challenge of development. The study pursues four research objectives which are: 1. to examine the environmental effects of cattle production by discussing the impacts of policies on disease control as well as changes in rangeland condition; 2. to discuss the social impacts of the modernisation approach to development by examining data on the distribution of cattle, the financial returns that accrue to owners, and the level of subsidies which the sector receives from the government; 3. to determine the degree of vulnerability of the Botswana cattle sector to decisions made outside the country by investigating the influence of the EEC and certain environmental groups on the beef industry. 4. to suggest a set of principles aimed at making development more ecologically sensitive, more beneficial to most people, and more self-reliant in terms of economic and political decisions. Modernisation theory according to Hirschman and Rostow contends that inter-dependence with capitalist economies is a prerequisite for development (primarily defined as economic growth and not addressing environmental issues); that the accumulation of wealth will lead to the reduction of poverty; and that all countries can benefit from the development process. By contrast, Dependency theory according to authors including Prebisch, Frank, Amin, and Sunkel has argued that inter-dependence with capitalist economies retards development; that the national accumulation of wealth does not lead to improved living conditions for much of the population; and that there is little prospect for economic growth in the peripheral countries. The analysis of policies and measures adopted by the Botswana government involving land reform, disease control, pricing and marketing policies and the use of subsidies reveals that economic growth and access to markets have been attained at the expense of both environmental quality and equity. Future policy for the livestock sector cannot ignore criticism of these impacts without jeopardising the beef trade which has largely been determined by the EEC. This European Community influence raises questions about the extent to which Botswana is in control of her development policy. Drawing largely from the work of Gardner, the thesis addresses the above concerns by suggesting a set of policy guidelines which identify both the ends and means of decision-making. This framework recognises that the goals of development must include ecological sustainability and economic and political self-reliance in addition to material benefits. Although it recognises the magnitude of the development problems, the thesis concludes by suggesting specific issues which should be investigated to improve living conditions in the country.
Applied Science, Faculty of
Community and Regional Planning (SCARP), School of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
5

Mmualefe, Lesego Cecilia. "Sample preparation for pesticide analysis in water and sediments a case study of the Okavango Delta, Botswana." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1005006.

Full text
Abstract:
This thesis presents a first ever extensive analysis of pesticides in water and sediments from the Okavango Delta, Botswana, employing green sample preparation techniques that require small volumes of organic solvents hence generating negligible volumes of organic solvent waste. Pesticides were extracted and pre-concentrated from water by solid phase extraction (SPE) and headspace solid phase microextraction (HS-SPME) while supercritical fluid extraction (SFE) and pressurized fluid extraction (PFE) were employed for sediments. Subsequent analysis was carried out on a gas chromatograph with electron capture detection and analytes were unequivocally confirmed by high resolution mass spectrometric detection. Hexachlorobenzene (HCB), trans-chlordane, 4,4′-DDD and 4,4′-DDE were detected after optimized HS-SPME in several water samples from the lower Delta at concentrations ranging from 2.4 to 61.4 μg L-1 that are much higher than the 0.1 μg L-1 maximum limit of individual organochlorine pesticides in drinking water set by the European Community Directive. The same samples were cleaned with ISOLUTE C18 SPE sorbent with an optimal acetone/n-hexane (1:1 v/v) mixture for the elution of analytes. No pesticides were detected after SPE clean-up and pre-concentration. HCB, aldrin and 4, 4‟-DDT were identified in sediments after SFE at concentration ranges of 1.1 - 30.3, 0.5 – 15.2 and 1.4 – 55.4 μg/g, respectively. There was an increase of pesticides concentrations in the direction of water flow from the Panhandle (point of entry) to the lower delta. DDE, fatty acids and phthalates were detected after PFE with optimized extraction solvent and temperature. The presence of DDT metabolites in the water and sediments from the Okavango Delta confirm historical exposure to the pesticide. However their cumulative concentration increase in the water-flow direction calls for further investigation of point sources for the long-term preservation of the Delta. The green sample preparation techniques and low toxicity solvents employed in this thesis are thus recommended for routine environmental monitoring exercises.
APA, Harvard, Vancouver, ISO, and other styles
6

Wong, Wing-sze, and 黃穎詩. "Water chemistry in the Kam Tin basin, natural and authropogenic influences." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38605843.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Madzwamuse, Masego S. "Adaptive livelihood strategies of the Basarwa: a case of Khwai and Xaxaba, Ngamiland district, Botswana." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1005286.

Full text
Abstract:
This thesis looks into the land use and natural resource management systems of Basarwa communities in Ngamiland in the northwest of Botswana. The study specifically focuses on Basarwa communities living in and on the edges of the Okavango Delta. The link between these communities and their natural resources is explored using the Sustainable Rural Livelihoods Framework and the Adaptive Renewal Cycle. The core assumption in this thesis is that livelihood strategies are constantly renewed and adapted to promote resilience in ecological and social systems. Fieldwork data collected between May 2000 and July 2001 and secondary data is used to deliberate on this point. The thesis confirms that the Basarwa’s livelihood strategies were adaptive only in as far as traditional livelihoods are concerned. The thesis traces the changes that the Basarwa have experienced as a result of policy restrictions through the different phases of the adaptive renewal cycle. The period following Independence in Botswana saw a policy shift which resulted in the Basarwa becoming landless. With mainly land-based livelihood strategies, the Basarwa were faced with new forms of crises and vulnerability which their traditional adaptive strategies were not designed for. It comes to the conclusion that the Basarwa are currently stuck in a reorganisation phase; however, the CBNRM Draft Policy of Botswana offers a glimpse of hope as it provides an opportunity for the Basarwa to progress through the full cycle of reorganisation, renewal, conservation and release.
APA, Harvard, Vancouver, ISO, and other styles
8

Dwyer, Brian James, University of Western Sydney, College of Social and Health Sciences, and School of Natural Sciences. "Aspects of governance and public participation in remediation of the Murray-Darling Basin." THESIS_CSHS_NS_Dwyer_B.xml, 2004. http://handle.uws.edu.au:8081/1959.7/776.

Full text
Abstract:
This thesis addresses the question “What is the essence of the Murray Darling river system conundrum that is usually posed as an issue of environmental remediation?”- following perceptions of problems in catchment strategy formulation regarding project selection and public consultation. The question is initially seen as having four facets – governance, public, participation and remediation. An initial literature review indicated that previous examination of these topics seemed insufficiently radical or comprehensive for the enquiry’s purposes, seeming not to attribute full humanness to members of the public. A fieldwork program of quasi-anthropological nature was conducted. Interpretation of the fieldwork reports focuses primarily on the lack of attribution of full humanness to members of the public. Interpretive techniques including a phenomenological-style process was applied and found that the district houses a number of unrecognised people “nexors’ occupying linking or nexus roles who exercise personal skills and initiatives to underpin effective remediation outcomes. Towards the end of the fieldwork program, further literature indicated that the initial four-facet nature of the enquiry should be reformulated, to include the overall nature of western society as it appears in the district (in place of participation), to reconstitute the concept of remediation more radically. Governance as a topic is broader than the ways in which it appears in the examined district, and suitable hybridizing of competing world view concepts remains unresolved in this thesis
Doctor of Philosophy (PhD)
APA, Harvard, Vancouver, ISO, and other styles
9

Fagbayigbo, Bamidele Oladapo. "Perfluorooctane acid (PFOA) and perfluorooctane sulfonate (PFOS) in the Plankenburg (Stellenbosch) and Diep (Milnerton) Rivers, and potential remediation using vitis vinifera leaf litter." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2668.

Full text
Abstract:
Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2017.
This study represents the first monitoring campaign to assess the seasonal trend of nine perfluorinated compounds (PFCs) in surface water and sediment from the Plankenburg and Diep Rivers in the Western Cape, South Africa. An analytical protocol was developed and validated for qualitative and quantitative routine determination of nine perfluorinated compounds (PFCs), in water and sediment samples using Ultra performance liquid chromatography-mass spectrometry quadrupole time of flight (UPLC-QTOF-MS). This method was applied to determine levels of PFOA and PFOS in environmental samples. Samples were collected along the Diep (Milnerton) and Plankenburg (Stellenbosch) Rivers respectively. Samples were pre-treated, cleaned-up and extracted using solid-phase extraction (SPE) procedures with hydrophilic-lipophilic balance (HLB) C-18 cartridges. Seasonal variation and distribution of PFCs in surface water and sediment was also investigated. Levels of PFCs were monitored in four seasons (summer, autumn, winter and spring) to establish their trend in the environment. The removal of PFOA and PFOS from aqueous solutions using agro-waste biomass of Vitis vinifera (grape) leaf litter was also studied. Activated carbons were produced from the biomass and chemical activation achieved with phosphoric acid (H3PO4) and potassium hydroxide (KOH) for the modification of the carbons’ (AC-H3PO4 and AC-KOH respectively). Activated carbons were characterized using Fourier Transform infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Brunauer- Emmett-Teller (BET) in order to understand the removal mechanisms of the contaminants by activated carbons. The effects of solution concentration, pH, adsorbent dosage, contact time, and the temperature were optimized for evaluation of the removal efficiency of the activated carbons. Adsorption isotherm models were used to analyze the equilibrium data obtained and kinetic models were applied to study sorption mechanisms. A fixed bed column study was conducted using: AC-H3PO4 adsorbent. Experimental parameters such as initial concentration of the solution, column bed height, flow rate and initial concentrations of the influent were optimized to establish the best adsorption efficiency parameters of the column system. Breakthrough curve and exhaustion time were predicted using Adam-Bohart, Yoon-Nelson, and Thomas models for the fixed bed column under varying experimental conditions.
APA, Harvard, Vancouver, ISO, and other styles
10

Mutingwende, Nhamo. "Identification of agricultural and industrial pollutants in the Kat River, Eastern Cape and their effect on agricultural products found along the river banks." Thesis, University of Fort Hare, 2015. http://hdl.handle.net/10353/d1020242.

Full text
Abstract:
There is growing concern that commonly used Pharmaceuticals and Personal Care Products (PPCPs) and pesticides are entering and contaminating drinking water supplies. The use of targeted quantitation of PPCP has been well established but there is an emerging trend to also screen for and identify unexpected environmental pollutants. Chemicals like pesticides hormones and antibiotics are especially of interest because of proven endocrine disrupting effects and a possible development of bacterial resistance. Powerful screening methods are required to detect and quantify the presence of these compounds in our environment. PPCP encompass a wide range of pollutants, including Endocrine Disrupting Compounds (EDC), pesticides, hormones, antibiotics, drugs of abuse, x-ray contrast agents and drinking water disinfection by-products to name a few. In order to properly assess the effects of these compounds on our environment, it is necessary to accurately monitor their presence. The diversity of chemical properties of these compounds makes method development challenging. LC/MS/MS is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range. The new AB SCIEX TripleTOF™5600 LC/MS/MS was used to profile environmental samples for unexpected pollutants, to identify and characterise the chemical composition and structure of the pollutants, and to quantify (based on intensity) the concentration in collected water samples. Liquid Chromatography coupled to tandem Mass Spectrometry (LCMS/ MS) is able to analyse polar, semi-volatile, and thermally labile compounds covering a wide molecular weight range, such as pesticides, antibiotics, drugs of abuse, x-ray contrast agents, drinking water disinfection by-products etc. More recently there is a growing interest from environmental researchers to also screen for and identify non-targeted compounds in environmental samples, including metabolites and degradates, but also completely unexpected pollutants. The new AB SCIEX TripleTOF™5600 LC/MS/MS system is capable of performing highly sensitive and fast MS scanning experiments to search for unknown molecular ions while also performing selective and characteristic MS/MS scanning for further compound identification and, therefore, is the instrument of choice for this challenging task. General unknown screening workflows do not use a target analyte list and compound detection is not based on any prior knowledge, including retention times and information on possible molecular and fragment ions. Therefore, acquired chromatograms are very rich in information and can easily contain thousands of ions from both any compounds present in the sample as well as from the sample matrix itself. Thus, powerful software tools are needed to explore such data to identify the unexpected compound. Water samples were collected both upstream and downstream of two WWTPs (Seymour and Fort Beaufort) and were directly injected on the AB SCIEX TripleTOF™5600 LC/MS/MS after being filtered. 15 sample points along the Kat River, ranging from a point as close to the source as possible to a point just before it joins the Great Fish River were used. The samples collected from the source were used as the control in each of the experiments, the assumption being the closer you get to the source, the less contaminated the water would be for the analysis of pesticides. Points were selected where the Kat River crosses the R67 or on farms where the river was accessible using farm roads. Samples were collected from October 2013 to November 2014.The Peak view software and Analyst software were used in the analysis of PPCPs. The XIC Manager allows you to manage large lists of compounds and perform automatic extracted ion chromatogram (XIC) calculations and review results operations. The results were displayed in the chromatogram pane and the XIC table (see results). The results reported here in this thesis indicate that there is contamination in the Kat River water due to both pesticides and PPCPs. The results also indicate that the food products are also contaminated and hence both the Kat River agricultural produce and its water need to be closely monitored for both pesticide and PPCPs contaminants. Further studies to investigate the quantitative levels of pesticides and PPCPs in the Kat river water to determine if the concentration levels of the detected pesticides are below the reported Maximum Residues Limits will be explored in the future.
APA, Harvard, Vancouver, ISO, and other styles
11

Mudumbi, John-Baptist Nzukizi. "Perfluorooctane sulfonate and perfluorooctanoate contamination of riparian wetlands of the Eerste, Diep and Salt Rivers." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2017.

Full text
Abstract:
Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2012.
Perfluorinated compounds (PFCs), in particular perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) have been found in aquatic environments throughout the world. Recent studies have reported that owing to their bioaccumulative nature, PFCs may also be present in various water sources, resulting in human and wild-life exposure. Although, these PFCs usually occur at low concentration levels, their presence in the environment has nevertheless been a concern in both developed and developing countries, since water remains an important natural resource for most living species. Water and sediment from rivers are one of the matrices in which PFC contamination is studied, since rivers receive water from various sources. However, limited studies have been conducted in South Africa on PFC contamination of river water and sediments. Although PFCs are sometimes unintentionally released into the environment, the concentration and type of PFCs that contaminate water sources vary among countries and depend on the types of industry releasing them into the environment, suggesting that PFC contamination patterns can be expected to differ from country to country, with PFOA and PFOS being the predominant perfluorinated contaminants. The aim of this study was therefore to determine the concentration of PFOS and PFOA in riparian wetlands of the Western Cape, focusing on the Eerste, Diep and Salt rivers, which are the primary rivers in the largest catchment areas of the Western Cape, South Africa.
APA, Harvard, Vancouver, ISO, and other styles
12

Williams, Chavon R. "A National survey of Mercury levels in South Africa's water management areas." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8674_1298356510.

Full text
Abstract:

This study forms part of a broader project co-funded by the Water Research Commission (WRC), and CSIR Parliamentary Grant (PG) and Strategic Research Panel (SRP) research grants, aimed at surveying selected water resources within the 19 Water Management Areas in South Africa. Furthermore, it aims at determining the concentrations of Hg and MeHg in various environmental compartments collected from priority water resources, to identify the potential Hg hotspots, and to assess the degree of compliance with national and international guidelines. Mercury concentrations in the environment have increased globally and this has caused much anxiety in terms of the adverse effects it has on aquatic ecosystems, their organisms, and the communities they sustain. Human health risks associated with the consumption of fish elevated containing Hg concentrations have received minimal attention particularly in South Africa. It is imperative that any potential adverse impacts of Hg on aquatic ecosystems, and the subsequent impacts on human health, be investigated.

APA, Harvard, Vancouver, ISO, and other styles
13

McGregor, Gillian Kathleen. "The geomorphological impacts of impoundments, with particular reference to tributary bar development on the Keiskamma River, Eastern Cape." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1005510.

Full text
Abstract:
The primary aim of this research was to develop and test a conceptual model of the geomorphological impacts of river regulation, based on a review of relevant international literature. It was motivated by the fact that there is very little local information on the topic, and it was intended that the model might provide a starting point for assessing the impact of impoundments on South African river systems. At present most research in South Africa on the impact of impoundments is undertaken from an ecological perspective. In order to manage our water resources sustainably it is necessary to have a better understanding of our river systems. South Africa is characterised by a variable climatic regime and, in order to supply water to the various user sectors of the nation, dams have to be larger than elsewhere in the world, to trap most of the mean annual runoff and provide a reliable water store (Alexander, 1985). South African dams have been designed to reduce the variability of a naturally variable regime. The impact of flow regulation in dryland rivers has been described as 'ecologically catastrophic at every level.' It is therefore hardly surprising that the impact of these dams on the natural functioning of rivers is substantial. The conceptual model showed that there are many responses to river impoundment, which are varied and complex, both in time and space. Responses or secondary impacts depended on the nature and degree of the primary impact or process alteration, on the sediment and flow regime of the river. High flows were affected in all cases and low flows were affected in most cases. The simplest form of change was Petts' (1979) concept of 'accommodation' of the regulated flow within the existing channel form. More complex responses occUrred where the channel perimeter was unstable, or where tributaries introduced fresh sediment loads. The river could adjust its long profile, cross sectional area and substrate composition by aggradation or degradation. The conceptual model was used in the Building Block Methodology to predict impoundment impacts at Instream Flow Requirement workshops on the Berg, Komati and Bivane rivers. It was also used in assessing the impact of the Sandile Dam on the Keiskamma river. Tributary junctions were identified as likely sites of change, and the morphology of bars at these junctions was investigated. Due to the number of variables affecting the sediment and flow regime in the system, and due to the fact that the primary impacts were not substantial, it was not possible to come to any decisive conclusions. It would seem that the dam is well located in the catchment, and, because the water is not heavily utilised, the secondary impacts are not great. The conceptual model was found to be a useful basic tool which might contribute to a better understanding of our river systems, and ultimately to improved sustainable resource management.
APA, Harvard, Vancouver, ISO, and other styles
14

Warlimont, Petra. "Application of the Tracking and Analysis Framework (TAF) to Assess the Effects of Acidic Deposition on Recreational Fishing in Maine Lakes." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/WarlimontP2002.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
15

Silo, Nthalivi. "Exploring opportunities for action competence development through learners' participation in waste management activities in selected primary schools in Botswana." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1003423.

Full text
Abstract:
The broader aim of this study is to probe participation of learners in waste management activities in selected primary schools in Botswana and through these activities, explore opportunities for action competence development. The study starts by tracing and outlining the socio-ecological challenges that confront children and the historical background of learner-centred education which gave rise to an emphasis on learner participation in Botswana education policy. It then maps out the development of children's participation in the global, regional and Botswana contexts by tracing the development of environmental education from early ecological and issue resolution goals of environmental education to sustainable development discourses. The focus is on policy issues and how learner participation has been represented and implemented in environmental education. The study then probes the rhetorical and normalised emphases on participation, and seeks further insight into how learners can be engaged in participatory learning processes that are meaningful, purposeful and that broaden their action competence and civic agency. The study uses the Cultural Historical Activity Theory (CHAT) methodology to build a picture of waste management activity systems in primary schools and to bring to the surface contradictions and tensions in learner participation in these activity systems. These contradictions are used to open up expansive learning participatory processes with learners using the Danish action competence framework. The expansive learning process uses action competence models that provide potential for transformative participation with learners, and new and different opportunities for learner participation. Case study research was used and conducted in the south eastern region of Botswana in three primary schools in three contexts, namely urban, peri-urban and rural. The data was largely generated through focus group interviews during workshops with children and observations of waste management activities. These two methods formed the main data generation methods. They were complemented by semi-structured interviews with teachers, and other actors in the waste management activities, learners' activities and work, learners' notes, photographs and children's drawings as well as show-and-tell explanations by learners. Content analysis and the abductive mode of inference were used to analyse data in all three case studies. Findings from the first phase of the study reveal that participation of learners in waste management activities was largely teacher-directed. This resulted in a mis-match between teachers views of what practices are necessary and important, and children's views of what practices are necessary and important in and for environmental education. Due to culturally and historically formed views of environmental education, the study reveals that teachers wanted children to pick up litter, and this was their primary environmental education concern. Learners on the other hand, identified sanitation management in the school toilets as their primary waste management concern. Teachers had not considered this an environmental education concern. Using the action competence expansive learning approach, the second phase of the study addressed this tension by opening up dialogue between teachers and learners and amongst the learners themselves through an expansive learning process supporting children's participation and action competence development. Through this teacher-learner dialogical engagement, a broader range of possibilities became available and ideas around participation were radically changed. The study further reveals that the achievement of this open dialogue provided for a better relationship within the school community. And with improved communication came better ideas to solve waste management issues that the community still face on a daily basis, such as too much litter. Newly devised solutions were practical and had a broader impact than the initial ones that teachers had always focussed on. They included mobilising the maintenance of toilets, landscaping the school premises and even re-contextualising the litter management that had always caused tensions between learners and teachers. Children seemed to be developing not only a better understanding of the environment, but also developing the ability to resolve conflict amongst themselves and with their elders. By engaging in dialogue with children, they became co-catalysts for change in the school community. This study shows that if children's participation is taken seriously, and if opportunities for dialogue exist between teachers and children, positive changes for a healthier environment can be created in schools. It reveals that children also appeared to be feeling more confident and more equipped to consider changes in their environment outside of the school community. The study further shows that participation in environmental education involves more than cognitive changes as proposed in earlier constructivist literature; it includes in-depth engagement with socio-cultural dynamics and histories in the school context, such as the cultural histories of teachers, schooling and authority structures in the cultural community of the school. The study recommends that there is need to strengthen Teacher Education programmes to develop teaching practices and support for teachers to identify ways of engaging learners' views on issues in the school in open, dialogical ways. Such Teacher Education programmes should deepen teachers' understandings of learners' zone of proximal development (ZPD), demonstrating how dialogue and scaffolding are part of a teacher's role in supporting learning. This is shown in the three case studies that form part of this study. Finally, the study also deepens insights of using the Cultural Historical Activity theory (CHAT) to shed light on issues surrounding learner participation within the socio-cultural and historical environmental education contexts of the schools. The action competence models used in the study provide a tool for revealing forms of learner participation. This tool can be used for critical reflections and monitoring of teaching practices in schools.
APA, Harvard, Vancouver, ISO, and other styles
16

Spencer, Erin Elizabeth. "Factors Controlling Alewife (Alosa psuedoharengus) Population Abundance among Four Rivers in Mid-Coast Maine." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/SpencerEE2009.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
17

Lake, Bjorn Anders. "The Use of Semipermeable Membrane Devices (SPMDS) for Monitoring Dioxin Levels in Maine Rivers." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/LakeBA2003.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

Williams, Margot Lluttrell. "Macroinvertebrate community and species responses to chlorinated sewage effluent in the Umsunduze and Umbilo rivers, Kwa Zulu-Natal, South Africa." Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1005413.

Full text
Abstract:
Chlorine has a wide variety of applications in water treatment. Because of its disinfectant efficacy, it is used world wide for the treatment of potable water, sewage, swimming pools and for the control of nuisance organisms in cooling towers. A problem arises when such chlorinated water enters the natural environment, as chlorine's greatest advantage, i.e. its germicidal capacity, becomes its greatest disadvantage. In particular, the discharge of heated, chlorinated water from cooling towers and chlorinated, treated sewage into rivers have severe consequences for the riverine flora and fauna. This study focused on the effects of chlorinated, treated sewage effluent on the community structure of benthic macroinvertebrates in two rivers in KwaZulu-Natal viz. the Umsunduze River in the Pietermaritzburg area, and the Umbilo River in the Durban area. The study was conducted in three phases. The first two phases comprised a toxicological investigation of the effects of chlorine on a selected riverine macroinvertebrate, and the third phase comprised an ecotoxicological investigation of the effects of chlorinated treated sewage on benthic macroinvertebrate community structure. The first phase of the study involved the development of an artificial stream system which would be suitable for determining the response of a selected macroinvertebrate species to chlorine. Chlorine is both reactive and volatile, so this necessitated the development of a specialised flow-through system with apparatus which would allow continuous dosing of a sodium hypochlorite solution. The system was set up at the Process Evaluation Facility at Wiggins Waterworks, Durban, where raw water from lnanda Dam was used. The second phase involved the use of this artificial stream system to conduct acute 96 h toxicity tests. Baetid mayfly nymphs (Baetis harrisoni Barnard) were selected as the test organisms after a preliminary investigation found them to be suitable for survival under laboratory conditions. For comparative purposes, tests were run first on B. harrisoni from a relatively uncontaminated stream in a residential area of Westville, then on specimens from the severely impacted Umbilo River. The LC₅₀ of chlorine for organisms from both sources was found to be in the region of 0.004 mg/l (free chlorine). This value was well below the general effluent standard of 0.1 mg/l in effect at the time. The recommended acute environmental guideline is 0.001 mg/l. The third phase of the study involved field validation of the toxicity test results. It was hypothesised that since the LC₅₀ for free chlorine was 0.004 mg/l, B. harrisoni would not be found downstream from a point source of chlorinated effluent where the concentration of free chlorine ranged from 0.06 to 0.2 mg/l, and that the macroinvertebrate community structure would also be altered. In order to test these hypotheses, benthic macro invertebrate community structure was investigated at several sites up- and downstream from the outlets of the Darvill Wastewater Works in the Umsunduze River and the Umbilo Sewage Purification Works in the Umbilo River. In addition, in order to differentiate between the effects of chlorinated and unchlorinated treated sewage, a section of the Umbilo River (upstream from the chlorinated discharge) was exposed to unchlorinated, treated sewage. In this way, a limited "before and after" sewage and an "upstream and downstream" from sewage investigation could be carried out. Organisms were collected from riffles (and from pools in the Umbilo River) and the samples were then sorted and organisms were identified to species level, where possible, otherwise to genus or family. Changes in community composition were shown graphically as pie charts of relative proportions of organisms found at each site, graphs of the average number of taxa at each site; and graphs of the average number of individuals at each site; Data from the Umbilo River were also analysed using TWINSPAN (Two-way indicator species analysis). In both the Umsunduze and the Umbilo rivers, the deleterious effects of the chlorinated effluent were clearly evident. At Umsunduze Site 3 and Umbilo Site 5 (both immediately downstream from the chlorinated effluent) both the number of taxa and number of individuals were substantially reduced, sometimes to zero. Where organisms were found at the next sites downstream (Sites 4 and 6 respectively), the samples were dominated by Chironomus. In contrast, the unchlorinated effluent in the Umbilo River caused very little difference in community structure. As predicted, B. harrisoni was not found in downstream samples in which chlorine was present, yet appeared to be relatively unaffected by the unchlorinated effluent, suggesting that chlorine, rather than the effluent was responsible for its absence at downstream sites. In conclusion, it would appear that while treated sewage effluent certainly causes changes in macroinvertebrate community structure, chlorination of this effluent leads to large scale destruction of the riverine community. This in turn delays the recovery process of the river, rendering a longer stretch unfit for use. The consequences of this delayed recovery are that the failure to meet the water quality requirements of the natural environment results in those of the other water users (agriculture, industry, domestic and recreation) not being met. This reduces the natural capacity of the riverine community to process organic waste and recover from the discharge of sewage effluent. Chlorination increases the distance of impaired water quality and environmental integrity which result from organically enriched treated sewage effluent. The results of the study indicated that the draft water quality guidelines for aquatic ecosystems, derived from inadequate data, and calculated with a safety factor, were the correct order of magnitude. The approach followed in the study will be useful in the development and refinement of water quality guidelines for aquatic ecosystems.
APA, Harvard, Vancouver, ISO, and other styles
19

Shaw, Gregory Alan. "Rehabilitation of the Orange River Mouth Salt Marsh : seed, wind and sediment characteristics." Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/603.

Full text
Abstract:
The Orange River is an important source of freshwater and like many other wetlands in semi-arid regions, supports various social (Spurgeon, 1998), economic (Spurgeon, 1998; Bornman et al., 2005) and ecological functions. The saltmarsh at the Orange River Mouth has become degraded over time following numerous anthropogenic impacts. As a result the Transboundary RAMSAR site was placed on the Montreux record emphasising the importance for rehabilitation. The potential of the marsh for natural rehabilitation was assessed through three physical factors which were considered to have the most influence on the saltmarsh i.e. 1) sediment 2) water 3) wind. Three sampling areas were chosen to investigate the sediment characteristics of the ORM saltmarsh and the suitability for seed germination and adult survival. Site A was representative of the general marsh area, Site B was thought to have favourable sediment conditions for saltmarsh growth because of the large numbers of seedlings and Site C was prone to inundation by wind blown sediment. The sites were sampled in 2005 (dry conditions) and in 2006 after high rainfall and river flooding. Electrical conductivity (EC) of the sediment throughout the marsh was hypersaline in many instances above the tolerance range for S. pillansii (> 80 mS.cm-1) The freshwater event in 2006 lowered salinity significantly in two of the three sites. Differences in sediment characteristics were also compared for three habitats i.e. driftlines, open sites and under vegetation. Driftlines (C. coronopifolia = 872 seedlings m-2; S. pillansii = 1296 seedlings m-2) and the microhabitat associated with adult plants (C. coronopifolia = 803 seedlings m-2; S. pillansii = 721 seedlings m-2) created favourable conditions for seedling growth, however open unvegetated (C. coronopifolia = 56 seedlings m-2; S. pillansii = 49 seedlings m-2) areas had significantly lower seedling density. Due to the marsh currently being in a desertified state this study aimed to establish whether the remaining vegetation could produce enough seed to revegetate the marsh. Laboratory studies indicated that seeds of both species germinated best in freshwater (0 psu). The germination of S. pillansii seeds was 40 percent at 0 psu compared to 5 percent at 35 psu. After storage under hypersaline conditions (35 psu) C. coronopifolia showed 100 percent seed germination when returned to freshwater whereas storage at 70 psu decreased the viability of S. pillansii seeds. The plants are producing adequate seed that will allow for regrowth and rehabilitation if sediment and groundwater characteristics are suitable for seed germination, seedling growth and adult survival. However the increase in bare areas at the Orange River mouth as a result of salt marsh dieback has increased the available sediment source. The wind blown sediment has covered large areas of the remaining adult salt marsh vegetation, particularly in the northern corner at Site C, causing further die-back.
APA, Harvard, Vancouver, ISO, and other styles
20

Foran, Tira. "Rivers of contention : Pak Mun Dam, electricity planning, and state-society relations in Thailand, 1932-2004." Connect to full text, 2006. http://hdl.handle.net/2123/1984.

Full text
Abstract:
PhD
This study investigates how actions – especially narratives and claims – of civil society advocates influenced electricity generation planning and hydropower project implementation, in the context of a democratising authoritarian state. To pursue this research agenda, I use a critical realist philosophy of science to ground a conceptual framework whose fundamental components consist of institutions, interests, and discourses. The research presents three case studies from Thailand, a nation-state with distinct authoritarian legacies, as well as significant economic and political dynamism in the late 20th century. The cases step from macro to micro levels of analysis: (1) Electricity generation planning: an overview and critique of the social construction of peak power demand and supply options in Thailand, 1960s–2004. I focus on the rise of energy conservation advocacy in the early 1990s, and the rise of more confrontational energy activism in the late 1990s; (2) Pak Mun Dam: contention between EGAT, anti-dam villagers, and other state and civil society actors, 1989–2003; (3) Pak Mun Dam: analysis of how knowledge discourses shaped debates over fisheries and local livelihoods in the lower Mun river basin, 1999–2004. I pursue these cases in the larger context of Thai state–society relations, 1932–early 2000s: from the Khana Ratsadorn (People’s Party) and its founders’ increasingly authoritarian struggles to shape the state; through to the rise of civil society in the Indochina-war era; through the emergence of parliamentary politics and NGO evolution in the 1980s and early 1990s; to the Thai Rak Thai “money politics” party that emerged in 1998. Specific research questions focus on patterns and outcomes of state–society interaction, the role of lay and expert knowledge discourses in structuring conflict, and plausible causal connections between outcomes and concepts used in the conceptual framework. The study is based on fieldwork conducted between 2001 and 2005, with 18 months of intensive work concentrated in 2002 and 2004. Recurrent procedures consisted of collecting policy narratives and arguments and re-constructing actors’ interests (including those of leaders in organizations) via participant observation, interviews, and textual analysis. The thesis argues that anti-dam advocates influenced project implementation practices at Pak Mun Dam by forming social change networks, gaining contingent recognition as new political actors. Through innovative and disruptive action, through claims for transparency and justice, through mass performances of worthiness, unity, and commitment, and through the production of local knowledge, they helped set agendas. They triggered elite intervention, as well as reactive counter-mobilization and occasional violence. The escalation of uncertainty from unintended outcomes challenged elites – aided by deliberative exchanges – to reconsider unfavourable decisions, to reconsider their preferences, and to make concessions. At the same time, a number of events made the Assembly of the Poor, the main anti-dam movement organization, vulnerable to destabilizing action at the local and national levels. These include: the formation of competitive organizations in the lower Mun basin; complex and intractable issues (such as multiple rounds of compensation); and inability to take credit for championing the interests of vulnerable small farmers. Destabilizing interactions occurred particularly in the restricted media space of the post-financial and economic crisis years. Populist platforms put forward by Thai Rak Thai and Prime Minister Thaksin Shinawatra pre-empted the AOP’s influence. Sustainable energy advocates influenced practices of power system planning by teaching new techniques of energy conservation, and diffusing new norms. In the recent period, however, as some of them engaged in more contentious interaction, such as intervening in conflicts over new coal and hydroelectric power plants (in southern Thailand and Laos respectively) they disrupted dominant rationalities, and found themselves confronting some of the same core practices of a power-wielding bureaucracy and an authoritarian state, namely rhetorical strategies that police the boundaries of policy-relevant knowledge. The thesis, intended to contribute to social science methodology and theory, concludes with a critical appraisal of the conceptual framework. I suggest new research agendas for analysts interested in mechanisms of civil society advocacy in the context of democratising states.
APA, Harvard, Vancouver, ISO, and other styles
21

Cuthbert, Iain Dawson. "Predicting the riverine concentrations and catchment exports of metals in rural drainage basins of Ontario and Québec." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60672.

Full text
Abstract:
Concentrations of Fe, Al, Mn and Zn were measured monthly from April to October at 24 rural riverine sites in Ontario and Quebec. Empirical models were developed predicting riverine metal concentrations from a small set of within-stream and catchment variables. Models explained a significant proportion of the variation in Fe (85%), Al (90%), Mn (57%) and Zn (37%). Simple models predicting annual catchment exports of metals from average riverine suspended particulate concentrations and runoff were also developed. These models explained most of the variation in annual exports of Fe (94%), Al (92%), Mn (62%) and Zn (75%) from the 24 catchments.
Models such as these can be used both to estimate catchment exports of metals to lakes, and to estimate riverine metal concentrations without requiring chemical analyses. The models also serve to distinguish background levels from those indicating metal contamination, and will, therefore, be useful in design of water quality guidelines.
APA, Harvard, Vancouver, ISO, and other styles
22

Beck, Julia S. (Julia Samantha). "Downstream changes in river morphology as a result of dam developments." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52243.

Full text
Abstract:
Thesis (MEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: A dam can have a significant impact on the downstream river morphology by altering both the flow regime and the sediment load. The effect of a dam is dependent on factors such as the storage capacity relative to the mean annual runoff (MAR), the operation of the reservoir and the sediment yield of the catchment. Changes in the river morphology include the degradation and coarsening of the riverbed, generally closer to the dam, and aggradation further downstream where the sediment delivered by tributaries cannot be carried through because of the reduced sediment transport capacity of the river. The impact of a dam can stretch over several hundreds of kilometres. The main objective of this thesis was to gain a better understanding of the impacts that dams can have on the downstream river morphology. This was done by developing equations that can describe the channel geometry, investigating the effect of the presence of clay and silt on the sediment transport behaviour of sediments, as well as detailed evaluation of simulations carried out with a one-dimensional mathematical river model (MIKE 11). The calibrated regime equations were found to be comparable to other internationally developed regime equations and to be suitable for natural rivers. It was found, however, that these regime equations are not applicable to rivers downstream of dams that have highly unnatural release patterns. Further research is needed in this regard. By investigating the effect of cohesive sediments on the sediment transport behaviour of mixed sediments it was found that as little as 7% clay and silt in the bed could affect their sediment transport characteristics. A methodology was also developed by which the critical conditions for mass erosion of cohesive sediments can be described in terms of the applied stream power. Sediment transport equations were calibrated and verified in terms of the unit input stream power for fine and non-cohesivesediments. The sediment transport equation for fine sediments was implemented in MIKE 11. The simulations over a 40 km reach of the Pongola River downstream of Pongolapoort Dam, have shown that even when a large demand is placed on the stored water, and most of the smaller floods are therefore absorbed by the dam, the downstream impact can still be considerable, with as much as 5 m deep erosion in places. The sediment loads are generally reduced (by as much as 35%), but the effective catchment area downstream of the dam has been reduced by as much as 90%, indicating that substantial erosion had to have taken place in the river. Coarsening of the riverbed was also observed during the simulations.
AFRIKAANSE OPSOMMING: 'n Dam kan 'n aansienlike impak he op die riviermorfologie stroomaf daarvan, deurdat dit beide die vloei en sedimentlading drasties kan verander. Die effek van 'n dam hang van verskeie faktore af, soos die opgaarkapasiteit in vergelyking met die gemiddelde jaarlikse afloop (GJA), die bestuur van die dam en die sedimentlewering van die opvanggebied. Veranderings in die riviermorfologie behels die degradering van die rivierbed, sowel as die uitspoel van fyn materiaal uit die rivierbed, veral nader aan die dam. Deponering vind verder stroomaf van die dam plaas, waar die sediment wat deur die sytakke ingevoer word nie deurgevoer kan word nie, weens die verlaagde sedimentdravermoe van die rivier. Sodoende kan rivierlope oor honderde kilometers deur 'n dam bemvloed word. Die hoofdoel van die tesis was om meer insig te verkry oor die impak wat damme op die stroomaf riviermorfologie kan he. Derhalwe is vergelykings ontwikkel wat die riviermorfologie kan beskryf. Die effek van die teenwoordigheid van klei en slik op die sedimentvervoer-eienskappe is ondersoek, en gedetaileerde ontledings is met 'n een-dimensionele wiskundige riviermodel (MIKE 11) is gedoen. Daar is bevind dat die regime-formules goed vergelyk met ander intemasionaalontwikkelde formules en dat hulle geskik is vir toepassing op natuurlike riviere. Daar is egter gevind dat die formules nie geskik is vir riviere wat stroomaf Ie van damme wat hoogs onnatuurlike loslatings het nie. Verdere navorsing is op hierdie gebied nodig. Ondersoek na die effek wat klei en slik op die sedimentdravermoe het, het getoon dat slegs 7% klei en slik in die rivierbed die sedimentvervoer-eienskappe van mengsels van fyn en growwe materiaal kan bemvloed. 'n Metode is ontwikkel waarmee die kritiese toestande vir massa-erosie van kohesiewe sediment beskryfkan word in terme van die aangewende stroomdrywing teen die bed. 'n Sedimentvervoer-vergelyking in terme van die eenheids-insetstroomdrywing vir fyn en nie-kohesiewe sedimente is gekalibreer en geverifieer. Die nuwe sedimentvervoer-vergelyking vir fyn sedimente is gebruik in die MIKE 11 simulasies. Hierdie simulasies oor 'n 40 km loop van die Pongolarivier stroomaf van Pongolapoort Dam, het getoon dat selfs as daar 'n groot aanvraag op 'n dam se water geplaas word, en gevolglik meeste van die kleiner vloede deur die dam geabsorbeer word, die impak van die dam nogs steeds aansienlik kan wees, met soveel as 5 m diep uitskuring in plekke. Die sedimentladings het gewoonlik verminder (met soveel as 35%), maar die die effektiewe opvanggebiedarea stroomafvan die dam het met meer as 90% verminder, wat daarop dui dat daar aansienlike erodering in die rivier plaasgevind het. Die simulasies het ook getoon dat die hoeveelheid fyn materiaal in die rivierbed verminder het.
APA, Harvard, Vancouver, ISO, and other styles
23

Guiseppe, Vincente E. "Radon in Ground Water: A Study of the Measurement and Release of Waterborne Radon and Modeling of Radon Variation in Bedrock Wells." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/GuiseppeVE2006.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Dawson, Emily Kathleen. "A river health assessment of selected South-Western Cape Rivers : index of habitat integrity, water quality and the influence of surrounding land use." Thesis, Stellenbosch : University of Stellenbosch, 2003. http://hdl.handle.net/10019.1/16297.

Full text
Abstract:
Thesis (MSc)--University of Stellenbosch, 2003.
ENGLISH ABSTRACT: The River Health Programme (RHP) is an assessment tool for monitoring the ecological state of rivers to ensure that they remain fit for use by present and future generations. This study, forming part of a RHP assessment conducted on the south-western Cape Hout Bay, Lourens and Palmiet Rivers, has the aim to (1) zone the rivers for representative site selection, (2) assess their habitat integrity (HI), (3) determine the influence of land use on riverine HI and (4) assess the river water quality at the time of the RHP assessments. (1) The desktop geomorphological zonation method used in RHP assessments has not been sufficiently previously tested on short rivers draining the Western Cape Mountains. The Lowland River Zone of the rivers studied, as well as the Hout Bay River’s Upper Foothill Zone, were found to have steeper gradients than expected, probably due to these rivers being shorter and consequently steeper than any on which the method was previously tested. The notion of one gradient river classification system being applicable throughout South Africa, with its diverse geology and climate, is unlikely. Rather a classification system modified for various physiographic features regions or by a factor based on river length is more realistic. (2) Although there is a general longitudinal decrease in HI downstream along the Hout Bay and Lourens Rivers, coinciding with increased anthropogenic activities, HI improves in the Palmiet River’s lower reaches through the Kogelberg Nature Reserve. Surrounding land use thus seems to be a major determinant of HI. Although the Index of Habitat Integrity (IHI) used appears to achieve its aim, it was found to be subjective. Categorisation of the IHI scoring is suggested. (3) The amount of natural versus disturbed land use occurring upstream of a site at a regional and local scale, is a good predictor of riverine HI. Regional alien forestry and local urbanisation have significantly strong negative effects on instream (r2 = -0.80, r2 = 0.80, p<0.05) and riparian (r2 = -0.81, r2 = -0.83, p<0.05) HI. Different land use types therefore appear to affect riverine HI at differing scales and thus managers must not only think on a local but also a catchment scale. (4) In the Hout Bay River, a filtering system (e.g. wetland) appears to improve the water quality between the middle and lower reaches. Along the Lourens River, high total dissolved salts, conductivity and inorganic nitrogen concentrations in the middle reaches are cause for concern. Along the Palmiet River there appeared to be insufficient oxygen to support most aquatic life forms at Grabouw. Impoundments in the middle reaches act as sinks for nutrients and salts, but the Huis and Krom tributaries downstream then appear to degrade the water quality of the Palmiet River’s lower reaches within the Kogelberg Nature Reserve. Together with the results of simultaneous biotic assessments, these results should be used to develop management actions to improve the ecological health of these rivers. The results have been used in a State-of-Rivers Report for the south-western Cape.
AFRIKAANSE OPSOMMING: Die Riviergesondheidsprogram (RGP) is 'n asseseringsinstrument wat die ekologiese stand van riviere monitor om te verseker dat hulle steeds bruikbaar bly vir huidige en toekomstige geslagte. Hierdie studie maak deel uit van 'n RGP-assessering van die Lourens-, Houtbaai- en Palmietrivier in die Suidwes-Kaap en het ten doel om (1) die riviere te soneer vir verteenwoordigende terreinseleksie, (2) die habitat-integriteit (HI) te assesseer, (3) die invloed van grondgebruik op rivier-HI te bepaal en (4) die kwaliteit van rivierwater tydens die RGP-assesserings te bepaal. (1) Die geomorfologiese-soneringsmetode wat in RGP-assesserings gebruik word, is nog nie voorheen genoegsaam vir die kort riviere wat die Wes-Kaapse berge dreineer, getoets nie. Daar is bevind dat die studiegebied riviere in die laagland-sones skerper gradiënte het as verwag, gehad het. Dit kan moontlik toegeskryf word aan die riviere wat korter en dus steiler is as enige van dié wat voorheen met die metode getoets is. Die moontlikheid dat een gradiëntklassifikasiestelsel vir riviere regdeur Suid-Afrika met sy diverse geologie en klimaat toegepas kan word, is onwaarskynlik. 'n Klassifikasiestelsel aangepas vir verskillende fisiografiese streke of met 'n faktor gebaseer op rivierlengte, is meer realisties. (2) Alhoewel HI stroomaf langs die Lourens- en Houtbaairivier in die algemeen longitudinaal saam met die toename in antropogeniese aktiwiteite afneem, verbeter die Palmietrivier se HI waar dit laer af deur die Kogelbergnatuurreservaat vloei. Die gebruike van aanliggende grond blyk dus 'n belangrike bepaler van HI te wees. Die Indeks van Habitatintegriteit (IHI) bereik klaarblyklik die vereiste doel, maar is te subjektief. Kategorisering van die IHI-waardes word voorgestel. (3) 'n Goeie voorspeller van rivier-HI is die hoeveelheid natuurlike teenoor versteurde grondgebruik stroomop van 'n terrein op 'n streeks- en lokale skaal. Die sterk negatiewe effek van uitheemse plantegroei in die omgewing en lokale verstedeliking op stroom- (r² = -0.80, r² = 0.80, p<0.05 ) en oewer-HI (r² = -0.81, r² = -0.83, p<0.05) is beduidend. Verskille in tipe grondgebruik beïnvloed rivier-HI op verskillende vlakke; bestuurders moet dus plaaslik en aan die opvanggebied dink. (4) In die Houtbaairivier lyk dit asof 'n filtreringstelsel (bv. vleigrond) die waterkwaliteit tussen die middel- en lae gedeeltes verbeter. In die loop van die Lourensrivier is hoë totale opgeloste soute, geleidingsvermoë en anorganiese stikstofkonsentrasies in die middelgedeelte 'n rede tot kommer. In die Palmietrivier by Grabouw was die suurstof te min om die meeste akwatiese lewensvorme te onderhou. Opgedamde water in die middel gedeeltes dien as 'n sink vir voedingstowwe en soute, maar dit lyk asof die Huis- en Kromrivier die waterkwaliteit van die Palmietrivier stroomaf in die Kogelbergnatuurreservaat degradeer. Saam met die resultate van gelyktydige biotiese assesserings, kan hierdie resultate gebruik word vir die ontwikkeling van bestuursaksies om die ekologiese toestand van hierdie riviere te verbeter. Die resultate is gebruik in 'n toestand-van-riviere-verslag vir die Suidwes-Kaap.
APA, Harvard, Vancouver, ISO, and other styles
25

Newman, Natalie Nicolette. "The impact of altered river structure on the function of selected urban Cape Town rivers." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/2029.

Full text
Abstract:
Thesis (MTech (Nature Conservation))--Cape Peninsula University of Technology, 2010.
Many urban rivers are heavily engineered and no longer function naturally. The City of Cape Town has designed and implemented many stormwater and river management projects. Very little monitoring has occurred as to whether these engineering projects and remediation measures, have had a positive effect on our urban river ecosystem function. The study investigated the influence of specific engineering interventions such as the placement or rocks in stream to create weirs, gabion lining of stream channels, removal of canal walls, establishment of artificial wetlands, and approaches to urban river management, on river ecosystem function of the Keysers River, Little Lotus River, Langevlei Canal, Silvermine River, Moddergat River and Big Lotus River, as measured by specific indices including water chemistry and aquatic community structure (macroinvertebrates and diatoms).
APA, Harvard, Vancouver, ISO, and other styles
26

Hayes, Johan Barnard. "Assessment of fish as bio-indicators of river health in rivers of the southwestern Cape." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52704.

Full text
Abstract:
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.
APA, Harvard, Vancouver, ISO, and other styles
27

Nkqenkqa, Vuyiseka. "Metal and microbial contamination of agricultural soil and the Veldwachters River, Stellenbosch, South Africa." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2423.

Full text
Abstract:
Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2017.
Surface water is used as a source of water supply in many countries, including South Africa. One of the sources of surface water pollution is leachate and surface runoff from landfills. In agricultural soils, the landfill runoff and leachate deteriorate the quality and affect the fertility of soil. The entry of metals and microorganisms from landfill leachate to adjacent environments is through surface runoff due to rainfall. Adverse effects on human- and environmental health triggers a need to monitor and control contaminants in the environment. The aims of the study are to determine the effect of landfill runoff and leachate on agricultural soil and river water (Veldwachters River) running adjacent to the Devon Valley landfill site and to identify potential metal-tolerant organisms in environmental samples collected in Stellenbosch, Western Cape, South Africa. Samples (agricultural soil, river water and sediments) were collected once a month for a period of six months from the study area for analysis. Physicochemical parameters that are known to have major effects on environmental samples were assessed and the concentrations of various metals (Al, Pb, Cr, Mn, Mo, Co, Ni, Cu, Zn, Fe, Cd and V) were also determined by means of inductively coupled plasma mass spectrometry (ICP-MS). Soil texture analysis was tested in order to monitor the metal distribution in soils under the influence of environmental factors.
APA, Harvard, Vancouver, ISO, and other styles
28

梁士倫 and Sze-lun Leung. "Scale-dependent effects of spatial and temporal variability on benthicmacroinvertebrate communities in Hong Kong streams." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243319.

Full text
APA, Harvard, Vancouver, ISO, and other styles
29

Talbert, Meredith Corea. "Understanding Sand Mining on the Maha Oya: The Conflict Between Economic and Environmental Survival." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/522.

Full text
Abstract:
River sand mining from the Maha Oya is the main source of income and a force that drives economic activity for residents along the river. This study takes place in Sri Lanka, there are three villages included in this project: Jambugaswatte, Janituspuraya and Thoppuwa. In Sri Lanka, sand serves as the main building material. It is used to make bricks, tiles, asphalt and concrete, therefore demanding a high market value. However, the over-extraction of sand comes along with significant environmental problems. These communities depend on the river in many ways and the health of the river directly corresponds to the health of the ecosystem as a whole. Along the Maha Oya two important elements of survival are in conflict with one another: residents simultaneously need a healthy, thriving ecosystem to live in, as well as economic opportunities. With support from the Environmental Foundation Ltd. (EFL)--a Sri Lankan environmental justice NGO--this study focuses on the complex situation with sand mining on the Maha Oya. Data for this study comes from fifteen formal interviews with a Sinhala-English translator. These interviews are used to address the two research questions for this project: how do village residents along the Maha Oya perceive sand mining? And what are the emotional, practical and theoretical responses of village residents to the effects of sand mining on their local ecosystems? In order to envision a sustainable future, it is vital to begin with a clear understanding of community perceptions of these complex issues, which are at the heart of this project.
APA, Harvard, Vancouver, ISO, and other styles
30

Muller, Matthew Justin. "Linking institutional and ecological provisions for wastewater treatment discharge in a rural municipality, Eastern Cape, South Africa." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1013048.

Full text
Abstract:
The Green Drop Certification Programme, launched in 2008 alongside the Blue Drop Certification Programme, aims to provide the Department of Water Affairs with a national overview of how municipalities and their individual wastewater treatment works (WWTW) are complying with licence conditions set by the National Water Act (NWA) (No. 36 of 1998; DWAF 1998) and the Water Services Act (No. 108 of 1997; DWAF 1998). By publishing the results of each municipality’s performance, the programme aims to ensure continuous improvement in the wastewater treatment sector through public pressure. The programme has been identified by this project as a necessary linking tool between the NWA and the Water Services Act to ensure protection and sustainable use of South Africa’s natural water resources. It does this through assisting municipalities to improve their wastewater treatment operations which in theory will lead to discharged effluent that is compliant with discharge licence conditions. These discharge licences form part of the NWA’s enforcement tool of Source Directed Controls (SDC) which help a water resource meet the ecological goals set for it as part of Resource Directed Measures (RDM). The link between meeting the required SDC and achieving the RDM goals has never been empirically tested. This project aimed to determine the present ecological condition of the Uie River, a tributary of the Sundays River which the Sundays River Valley Municipality (SRVM) discharges its domestic effluent into. It then determined whether the SRVM’s WWTW was complying with the General Standard licence conditions and what the impact of the effluent on the river was through the analysis of monthly biomonitoring, water chemistry and habitat data. Lastly, the project examined the effectiveness of the Green Drop Certification Programme in bringing about change in the SRVM’s wastewater treatment sector, which previously achieved a Green Drop score of 5.6 percent. It wanted to examine the underlying assumption that a WWTW which improves its Green Drop score will be discharging a better quality effluent that will help a water resource meets the RDM goals set for it. The Kirkwood WWTW did not have a discharge licence at the time of assessment and was thus assessed under the General Standard licence conditions. It was found that the Kirkwood WWTW was not complying with the General Standard discharge licence conditions in the Uie River. This was having a negative impact on the river health, mainly through high concentrations of Total Inorganic Nitrogen (TIN-N), orthophosphate and turbidity. The SRVM should see an improvement in its Green Drop score for the Kirkwood WWTW. However, the municipality showed no implementation of necessary programmes. Implementation of these programmes would help the SRVM meet the General Standard licence conditions (part of SDC) which would help the Uie River meet the RDM goals set for it.
APA, Harvard, Vancouver, ISO, and other styles
31

Lonergan, Sean P. "Macroinvertebrate community responses to acidification : isolating the effects of pH from other water chemistry variables." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68205.

Full text
Abstract:
The effect of lake acidification was evaluated, in the field, in terms of its impact on both the structural and functional composition of the macrozoobenthic community. The littoral macrozoobenthic community and water chemistry of 45 Canadian Shield lakes was sampled. The water chemistry variables sampled included pH, total dissolved calcium, conductivity, and dissolved organic acid (measured as colour). Partial canonical correlation analysis and partial regression analysis were used to identify those components of the macrozoobenthic community that most directly reflected pH variability. This was done by first removing from the data that portion of the variability attributable to total dissolved calcium, conductivity, and dissolved organic acids. In addition, the spatial structure in the data was removed by identifying the geographic coordinates of the sampling sites.
In general, the results presented here are not consistent with previous studies where the response of the macrozoobenthic community was related to pH without consideration of confounding covariables. Snails, leeches, mayflies and crayfish have all been cited for their sensitivity to acidification. The present study found these taxa to reflect, not pH variability, but rather attributes of water hardness. Similar results were found for both total zoobenthic biomass and functional feeding group abundance.
APA, Harvard, Vancouver, ISO, and other styles
32

Riley, Timothy. "Trans-boundary river basins: a discourse on water scarcity, conflict, and water resource management." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4396/.

Full text
Abstract:
This thesis is an inquiry regarding the interconnections between water scarcity, geopolitics, resource management, and the strategies for developing effective ways to resolve conflict and encourage sustainable water resource use in developing countries. The ecological services of trans-boundary rivers are explored in conjunction with the potential impacts to freshwater availability due to economic modernization, water resource development, and decision making regimes that determine how water is allocated among competing users. Anthropogenic stressors that induce water scarcity and the geopolitical mechanisms of conflict are studied. A discourse on the creation and functional extent of global and localized water ethics is investigated, emphasizing the importance of perceptual dispositions of water users in understanding the value of trans-boundary river basins.
APA, Harvard, Vancouver, ISO, and other styles
33

Wearing, Catherine Louise. "Changes in fluxes of dissolved organic carbon (DOC) from small catchments in central Scotland." Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/368.

Full text
Abstract:
Concentrations of dissolved organic carbon (DOC) measured within water bodies have been increasing on a global scale over the last two decades. Changes in temperature and rainfall have been shown to increase the production and export of DOC from catchments with peat soils in the UK (Freeman et al., 2001). However it is not clear whether increases in DOC concentrations are caused by production increases induced by temperature changes or by a greater incidence of high flows induced by rainfall changes. Increases in both temperature and rainfall have been predicted in Scotland over the next few decades (Kerr et al., 1999) which may further increase current DOC concentrations and exports. The implications of this include both a decrease in water quality and an increase in mobility of metals in upland water bodies. The overall aim of the thesis is to determine if the relationship between dissolved organic carbon (DOC) concentrations and discharge has changed over a 20 year period in small stream catchments in Scotland, in order to better understand the role of hydrology, in driving changes in DOC concentration. To achieve this streams draining two coniferous forest sites and one moorland site were monitored intensively between June 2004 and February 2006. Analysis of the relationship between DOC and discharge, within the catchments, identified the importance of the amount of precipitation falling on the catchment, antecedent precipitation and season, on the concentration of DOC that was measured within the stream. Models were then developed using variables to represent these drivers in terms of both the production (seasonal sine values and 14 day average temperatures) and movement (log of discharge (log Q), days since previous storm event and rising or falling stage) of DOC. In the Ochil Hills catchment, the best predictive model, used 4 hour average discharge and 1 day average 30cm soil temperatures (R2= 0.88). In the Duchray and Elrig catchments, the best predictive models produced used discharge and seasonal sine values; the strength of the model was greater in the Elrig (R2= 0.80) than the Duchray (R2= 0.48) catchment. The strength of the regression models produced highlighted the importance of precipitation in the movement of DOC to the stream and temperature variables representing production in the surrounding catchment. To determine if dissolved organic carbon (DOC) concentrations had changed within the three study catchments, since previous research was conducted at the same sites in the early 1980s and 1990s (Grieve, 1984a; Grieve, 1994), then regression analysis conducted in the previous research was repeated, so changes in the DOC and discharge relationship could be identified. Analysis of the Ochil Hills regression equations identified higher log of discharge and lower temperature and seasonal sine values in the present study (2004-06), when compared to the previous study (1982-83). This suggests that more DOC is now available for movement from the soil, and that the difference between winter and summer DOC production has decreased, potentially because of increasing temperatures. This would explain the limited increase in DOC concentration within the Ochil Hills stream. In the Duchray and Elrig streams, a large increase in DOC was identified at all discharges when all the models produced were compared between the two sampling periods (1989-90 and 2004-06). The increasing trend in DOC concentrations is too large to have been produced by change in temperature alone and it is suggested that the measured reduction in acidic deposition has resulted in the increased DOC concentrations measured in the Duchray and Elrig. The results from this research have identified that concentrations of DOC have increased in Scottish streams over the last 20 years and that the increases in DOC have been induced, potentially by temperature changes in climate. However, changes in temperature are not the only driver of this change as the reduction in acidic deposition is potentially more important, specifically in areas with base poor geology such as the Duchray and Elrig catchments.
APA, Harvard, Vancouver, ISO, and other styles
34

Lacher, Laurel Jane 1964. "Recharge characteristics of an effluent dominated stream near Tucson, Arizona." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/191199.

Full text
Abstract:
Almost 90% of the treated sewage effluent processed by the two treatment plants serving the greater Tucson area is available for passive recharge through the Santa Cruz River streambed north of Tucson. In the absence of any major disturbance of the effluent channel, the recharge capacity of the streambed materials decreases over time as microbial activity, and possibly suspended sediments settling out of solution, act to clog the surficial sediments under the effluent stream. Effluent stream transmission-loss measurements made over the period from November 1994 to August 1995 provided data used to determine the average vertical hydraulic conductivity of the low-flow channel in the study reach through simulations using the computer model known as KINEROS2. Saturated hydraulic conductivity (KSAT) served as the calibration parameter in the model. The appropriate KSAT value was chosen for each set of field data by matching the observed and simulated downstream hydrographs for the study reach. KSAT values were corrected for viscosity changes resulting from changing average daily surface water temperatures over the study period. Saturated hydraulic conductivity values for the effluent stream channel ranged from a maximum of 37 mm/hr in January, 1995, following several major winter storms, to a minimum of 11 mm/hr in August, 1995, after a nearly six-month interstorm period. The saturated hydraulic conductivity values decay exponentially with time after the last major winter storm. The mathematical model describing this decay may be used to estimate effluent recharge rates under similar future meteorological and climatological conditions.
APA, Harvard, Vancouver, ISO, and other styles
35

Broomall, Phillip A. "Physical and chemical limnological study of an acid mine lake in Sullivan County, Indiana." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/861393.

Full text
Abstract:
Southwestern Indiana has numerous lakes developed in abandoned coal mine spoils which support recreational sports fisheries. Some lakes, due to exposure to acid mine drainage from coal wastes and pyritic spoils, are unsuitable habitats for fisheries development. This study examines a publicly owned acid mine lake with an area of approximately 51 ha, following reclamation and elimination of acid producing areas in its drainage basin. Fifteen physico-chemical sample collections were made over a thirteen month period (1991-1992). Parameters sampled included pH, total acidity, iron, manganese, and aluminum. Comparisons were made to historic pre-reclamation water quality data and to established models of acid mine lake recovery. Due to the local topography and exposure to prevailing winds, the lake was generally well mixed throughout the study. Virtually no summer stratification was found, but typical winter season stratification occurred. The water column was well oxygenated throughout the study. Secchi disk transparency varied from 2.5 m to clear to lake bottom (6 m). This study found no significant change in lake water pH (2.9-3.0 to 3.0-3.2 s.u.) since reclamation activities in 1988. However, changes in total acidity and total metal concentrations had occurred since reclamation which suggested that the lake was in early recovery stages. No trends in water quality improvement were determined which could assist in planning toward the eventual establishment of a sports fishery.
Department of Biology
APA, Harvard, Vancouver, ISO, and other styles
36

Ashwell, Alice Nicola. "Project water (Grahamstown) : a case study of the development of an environmental education project." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1003599.

Full text
Abstract:
Environmental education is an approach to education which emphasises the interrelatedness of people and their human and non-human environments and seeks to encourage environmental awareness, concern and action. This case study documents the implementation and development of Project WATER, Grahamstown, a practical environmental education project dealing with catchment conservation and water quality monitoring. The Grahamstown project is one of a number of local water quality monitoring initiatives affiliated to GREEN (the Global Rivers Environmental Education Network). Participants in the project included student teachers from the Department of Education at Rhodes University and pupils and teachers from three farm schools in the district and four high schools in the town. Project WATER, Grahamstown developed as an Action Research and Community Problem-Solving project. The study focuses on fragmentalist and holistic approaches to education, people's responses to Project WATER and the choice of action research as the research method.
APA, Harvard, Vancouver, ISO, and other styles
37

Yau, Yick-yee Joyce, and 丘奕怡. "Bacterial indicators for beach water quality." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31254445.

Full text
APA, Harvard, Vancouver, ISO, and other styles
38

Jennings, Michael Evan. "Nutrient dynamics in and offshore of two permanently open South African estuaries with contrasting fresh water inflow." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1005421.

Full text
Abstract:
The nutrient dynamics in two contrasting estuaries and in the adjacent nearshore environment along the south-east coast of South Africa was investigated seasonally. Due to an inter-basin transfer of water from the Gariep Dam to the Great Fish River, the Great Fish estuary is a fresh water dominated, terrestrially driven system with an annual fresh water inflow of 250 – 650 x 10⁶ m³ per year. In contrast, the Kariega estuary is a fresh water deprived, marine dominated system with a fresh water inflow estimated at 2.5 – 35 x 10⁶ m³per year. The reduced fresh water inflow into the estuary is attributed to regular impoundments along the Kariega River. Water samples were collected from surface and subsurface layers along the length of the estuaries as well as from a series of transects occupied in the nearshore environment. Samples were analysed for nitrate, nitrite, ammonium, phosphate and silicate. Temperature and salinity were recorded at each station. A Land-Ocean Interactions in the Coastal Zone (LOICZ) budget was constructed for each estuary to describe the role of ecosystem-level metabolism as either a sink or a source of phosphorus, nitrogen and carbon. Seasonal variation in physico-chemical properties and nutrient concentrations in the Kariega estuary was minimal due to constant low inflow, while in the Great Fish estuary, concentrations varied in response to changes in flow rate. Nutrient concentrations were consistently higher in the Great Fish estuary than in the Kariega estuary, largely reflecting differences in fresh water inflow. During periods of high flow (32.92 m³.s⁻¹in the Great Fish River) dissolved inorganic nitrogen (DIN) concentrations in the Great Fish estuary were an order of magnitude higher than those recorded in the Kariega estuary. Results of the LOICZ budgeting procedures revealed that in spite of the contrasting hydrodynamic features, the estuaries behave in largely the same manner – both predominantly sources of nutrients with heterotrophic processes dominating over autotrophic actions and both were net denitrifyers during all surveys. This was, however, due to different sets of processes operating in the two estuaries, namely low nutrient concentrations resulting in microbial activity in the Kariega estuary, and riverine influx of nutrients and phytoplankton combined with a short residence time of the water in the Great Fish estuary. In the marine nearshore environment, higher nutrient concentrations were recorded adjacent to the Great Fish estuary than offshore of the Kariega estuary. This was due to a surface plume of less saline water leaving the Great Fish estuary, which acted as an ‘outweller’ of nutrients. Offshore of the Kariega estuary, on the other hand, the nutrient concentrations were characteristic of marine waters due to a lack of fresh water outflow from the estuary. Nutrient concentrations in the marine environment adjacent to the Kariega estuary were, at times, higher than those recorded within the estuary. This observation supports previous statements which suggest that the Kariega estuary is not an ‘outweller’ of dissolved nutrients and particulate material, but rather an extension of the marine environment.
APA, Harvard, Vancouver, ISO, and other styles
39

Martin, Paul Craig. "Radiological impact assessment of uranium mining and milling." Thesis, Queensland University of Technology, 2000.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
40

Pham, Huynh Anh. "The dynamics of microbial ferric and sulfate reduction in acidic mine lake sediments and their impact on water quality." University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0004.

Full text
Abstract:
[Truncated abstract] Acidic mine lakes are formed as a result of the oxidation and dissolution of metal sulfide minerals and are primarily characterized by low pH values of 2 – 4. Many strategies for the bioremediation of acidic mine lakes depend on the alkalinity generation capabilities of microbial ferric and/or sulfate reducing bacteria. However nearly all mine lakes are oligotrophic, with very low concentrations of available organic carbon and nutrients; all required for healthy microbial growth. There is also an unusual class of mine lakes characterized by low concentrations of organic carbon and also very low concentrations of dissolved iron and sulfate. Our ability to promote microbial activity in these systems is especially challenging. This study focuses on one of these systems, Lake Kepwari, a coal mine lake in Western Australia. Numerical modeling of remediation strategies is an efficient way of testing scenarios prior to expensive in-field trials. However such modeling relies on good descriptions of microbial processes, including kinetic parameterizations of ferric and sulfate reduction. There has been little research to date on the study of kinetic parameterizations of the chemical and biological alkalinity generation in acidic mine lakes. The objectives of this thesis were to investigate the viability of microbial ferric and sulfate reduction in an ultraoligotrophic, acidic mine lake, to assess the impact of these microbial processes on water quality and to parameterize the Dual Monod kinetics of neutralization under dual limitation conditions. Molecular analyses including most probable number, DNA extraction, polymerase chain reaction, polymerase chain reaction – denaturing gradient gel electrophoresis were used to examine the microbial communities in the lake sediments. ... The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and ferric, and as determined in batch experiments, were 0.07 ± 0.01 and 0.048 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants and were 14.37 and 5.6 mmol L-1. The Monod maximum consumption rates under ferric and OC limitation were also estimated. The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and sulfate, , and were 0.05 ± 0.01, 0.08 ± 0.01 and 0.07 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants, and were 75.5, 131.8 and 10.2 mmol L-1. The Monod maximum consumption rates under sulfate and OC limitation were also estimated. The results of this study suggest that strategies for the remediation of ultraoligotrophic, acidic mine lakes may rely on microbial ferric and sulfate reduction, however additions of both organic carbon and sulfate/ferric are essential. These results can be immediately applied to mesocosm studies in outdoor enclosures and to the management of acidic mine lakes. Furthermore, this thesis has provided a new, valuable understanding on the Dual Monod kinetic parameterizations of neutralization for an ultraoligotrophic, acidic mine lake environment. These parameterizations are essential for the lake ecological models that will be used to investigate remediation scenarios for acidic mine lakes.
APA, Harvard, Vancouver, ISO, and other styles
41

Motsholapheko, Moseki Ronald. "Developing integrated management of ephemeral river basins in Botswana : the case of Boteti river sub-basin." Diss., 2009. http://hdl.handle.net/10500/2697.

Full text
Abstract:
Botswana is a water scarce country. Rainfall is highly variable, leading to limited surface and groundwater resources. Due to persistently dry conditions most rivers found in Botswana are ephemeral. The Boteti River sub-Basin is one of the numerous ephemeral river sub-Basins, in Botswana. Key environmental challenges, resulting from human activities, in the sub-Basin are: increased pressure on local resources due to overstocking, overgrazing and over-harvesting; reductions in wildlife numbers; denudation of vegetation and the resultant exposure of the soil to wind erosion. As a major step, to pilot implementation of river basin management in the ephemeral river basins in southern Africa, the Boteti River sub-Basin is one of the key areas identified for study under the Ephemeral River Basins in the Southern African Development Community SADC (ERBSADC) Project. This study was initiated, as part of the ERB-SADC project and its aim is to investigate the socio-economic status of the Boteti River sub-Basin and determine the potential for developing integrated management of water and land resources in the sub- Basin. Its key objectives are to identify and assess types and patterns of water use; to identify and assess key livelihood activities; and to critically assess community participation in water resources management in the sub-Basin. A questionnaire was administered to 293 households, a focus group discussion was held with twelve community representatives of six villages in the sub-Basin, six traditional leaders and five local government officers were interviewed as key informants, and informal discussions were held with three local farmers. Results from the study indicate low livelihood levels based on livestock and arable agriculture, high dependence on natural resources and low participation of communities in water management. The study concludes that a livelihood approach to integrated water resources management can help deal with environmental challenges and enhance community participation.
Environmental Sciences
Thesis (M.A. (Environmental Science))
APA, Harvard, Vancouver, ISO, and other styles
42

Stewart, Gregory B. "Patterns and processes of sediment transport following sediment-filled dam removal in gravel bed rivers." Thesis, 2006. http://hdl.handle.net/1957/1815.

Full text
Abstract:
Graduation date: 2006
Dam removal is increasingly viewed as a river restoration tool because dams affect so many aspects of river hydrology, geomorphology, and ecology; but removal also has impacts. When a dam is removed, sediment accumulated over a dam’s lifetime may be transported downstream; and the timing, fate and consequences of this sediment remain some of the greatest unknowns associated with dam removal. In this thesis, I develop a conceptual model for erosion and deposition following removal of sediment-filled dams in mountain streams, and use field studies to document actual change. The data show that reservoir erosion in mountain rivers is likely to occur by knickpoint migration, with 85% of stored sediment being released during a single storm event in two field studies, at shear stresses less than that required for mobilization of the median surface particle size. Coarse sediment is predicted to deposit close to the dam with channel aggradation decreasing exponentially with increasing distance downstream, although some channel features are shown to have a greater propensity for aggradation than others. Field studies show that turbidity associated with dam removal and reservoir erosion may decrease hyporheic exchange, but gravel deposition (e.g., 470 m3 of gravel from Dinner Creek Dam) has the potential to more than offset that decrease, and increased hyporheic exchange is shown to reduce diurnal temperature change. Macroinvertebrate density and taxa richness did not respond to dam removal itself, but rather with time-lagged reservoir erosion. Following reservoir erosion, macroinvertebrate density recovered quickly, although longterm taxa community composition appears to be altered. On the Sandy River, field measurements of shear stress and patterns of sediment deposition following cold lahars were used as an analog to predict the fate of fine sediment, which is likely to deposit far from the dam. Results show that the Sandy River has little capacity for fine sediment storage in pools above RK 6.4 (~ 42 kilometers below Marmot Dam) at discharges associated with reservoir sediment releases. Taken as a whole, this paper illustrates a complex suite of process that may accompany removal of sediment-filled dams in mountain rivers.
APA, Harvard, Vancouver, ISO, and other styles
43

"The impact of tourism on agriculture in the Okavango Delta, Botswana." Thesis, 2003. http://hdl.handle.net/10413/3957.

Full text
Abstract:
In recent years the use of tourism as a development strategy by third world governments has increased, resulting in the intersection of international tourism and local agricultural strategies. The aim of this thesis is to critically assess the impact of tourism development on local agriculture in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and agriculture in the Okavango Delta, assesses the social, economic and environmental effects of tourism development on the Okavango Delta and its communities, examines local agricultural production and consumption patterns, assesses the patterns of supply and demand of food in the region, and evaluates the impact of tourism on local subsistence agriculture, while making use of both qualitative and quantitative data sources. The Okavango Delta region is faced with several socio-economic problems. These include high unemployment levels, unequal regional development, income inequalities and extreme levels of poverty. 'Rural-urban' migration by local subsistence farmers in search of formal employment opportunities has risen steadily since the early 1990s, resulting in unprecedented social changes to the inhabitants of the Delta, and the abandonment of traditional farming practices. This, together with the limited interaction between the local population and tourism industry, is increasingly leading to tension between local and foreign parties in the region. The large proportion of foreign owned tourist facilities and foreign investment results in major economic leakages, and the exclusion of Motswana from any form of meaningful participation in the tourism industry. The presence of foreign tourists in the Delta enforces the need for imports, increasingly damaging local agricultural production as both production and consumption becomes imported. If tourism is to be of any benefit to the local population in the Okavango Delta, there has to be local involvement and ownership. The fostering of linkages between tourism and other sectors, particularly agriculture, is imperative in attempting to bring about socio-economic growth in this region.
Thesis (M.A.)-University of Natal, Pietermaritzburg, 2003.
APA, Harvard, Vancouver, ISO, and other styles
44

Madyise, Tariro. "Case studies of environmental impacts of sand mining and gravel extraction for urban development in Gabarone." Diss., 2013. http://hdl.handle.net/10500/13896.

Full text
Abstract:
Economic development is one of the main objectives of developed and developing nations worldwide. Development comes with growth of urban areas. Urban growth is achieved through sand and gravel mining for construction of modern, attractive and durable structures. The study examined positive and negative environmental impacts of the continuous removal of river sand, pit sand and gravel from sampled rivers and open areas surrounding Gaborone developing Central Business District, malls and private properties in city. Quantitative and qualitative research designs that is questionnaire survey, oral interviews, field observation and measurements were used to collect data from selected sampled points. Metsimotlhabe and Ditlhakane rivers were selected because they are nearer to Gaborone and most river sand is mined from these rivers. More points were sampled from open areas in Kumakwane, Kopong and Bela Bela farms where pit sand and gravel are mined. Convenience and purposive sampling methods were used to pick questionnaire survey respondents (175) from Kumakwane and Metsimotlhabe villages where people affected lives. Findings of the study highlighted that river sand was mined most from rivers near Gaborone compared to pit sand and gravel because of its multi uses. Mining is important for economic development, to construct durable, modern structures, employment creation and revenue collection but removal of river sand leads to deepening and widening of rivers. Artificial rivulets are formed as resource is extracted uncontrollably. Pit sand and gravel are extracted from open areas creating uncovered deep pits, which caused of accidents to children and livestock. Erosion and environmental degradation occur due to continuous mining. Miners dispose waste on open areas and riverbeds causing land pollution. Dust and noise pollution from tipper trucks ferrying sand and gravel are a cause of concern to villagers as the trucks move even at night, disturbing sleep. Solutions to uncontrolled mining include 24 hour security and regular raids on illegal miners. The author recommends that heavy penalties should be imposed to curb illegal mining. High level decision making forum involving all stakeholders is necessary to discuss problems of illegal mining and how to limit negative impacts. Department of Mines need to develop an Environmental Management Plan and a close monitoring program nationwide.
Environmental Sciences
M. Sc. (Environmental Management)
APA, Harvard, Vancouver, ISO, and other styles
45

Kilsby, Nadine N. "Reach-scale spatial hydraulic diversity in lowland rivers: characterisation, measurement and significance for fish." 2008. http://hdl.handle.net/2440/49904.

Full text
Abstract:
Hydraulic conditions (velocity, depth, turbulence) strongly influence the distribution and abundance of organisms in rivers. A diverse hydraulic environment should foster biodiversity, because organisms have different hydraulic preferences. In fact, the relationship between spatial hydraulic diversity and biodiversity is largely presumed, and not well-supported by empirical studies, but it underpins efforts in river restoration and conservation. This is particularly so at the reach scale, indicating a stream- or river-section with large-scale homogeneous geomorphic and hydrological conditions and smaller-scale habitat patches, as perceived by organisms in the community under study. This thesis considers the factors that create spatial hydraulic diversity, and the ways that fish respond. It presents a method to characterise hydraulic diversity, and uses this to describe temporal and spatial changes between reaches. It also demonstrates the use of hydraulic modelling for comparing reaches. Finally, it assesses the Acoustic Doppler Current Profiler (ADCP) as a method to describe hydraulic conditions in a large, open river channel. Swimming ability tests were applied to three small freshwater fish, the pelagic Australian smelt (Retropinna semoni) and common galaxias (Galaxias maculatus ) and the demersal flathead gudgeon (Philypnodon grandiceps). The latter species was the weaker swimmer, but the tests indicated that behaviour also should be considered. A laboratory experiment was designed to investigate how two species with contrasting ecological habits (common galaxias, flathead gudgeon) behave in a diverse hydraulic environment. Habitat choices and activity were monitored in a constructed sinuous channel at three discharges over a 3-hour period. The galaxias favoured the pelagic habitat, and spent 20-60% of the time cruising, whereas the flathead gudgeon preferred the demersal habitat and spent <6% of the time cruising. The flathead gudgeons could access their preferred habitat at all discharges, but the common galaxias were limited by their swimming ability at the highest discharge. Several methods to characterise reaches were compared for eight 3-D model reaches representing the effects of channel form, wood and aquatic plants. The variogram (a measure of the variance between samples as a function of distance) emerged as a superior method because it indicates hydraulic diversity, incorporates the spatial arrangement of hydraulic patches, and facilitates comparisons between reaches. The ADCP proved a quick, reliable means to measure depth and 3-D velocity in rivers. It was effective only in depths >1.5 m, but modified instrumentation may overcome this limitation. Six reaches, including weir-pool and free-flowing sections, were compared at two discharges in the River Murray, Australia. Variograms derived from the ADCP data clearly demonstrated spatial differences between the sections, but temporal differences were less well-defined, suggesting that reaches may retain characteristic hydraulic patterns despite changes in discharge. Opportunities for further research include: the issue of optimal levels of hydraulic diversity for fish and other biota; use of variograms as a tool for field studies of aquatic biota; and measuring reach-scale hydraulic diversity and biodiversity before and after reach manipulation (e.g. the placement of wood), to elucidate the effects of changes in spatial hydraulic diversity on reach biodiversity.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1344602
Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2008
APA, Harvard, Vancouver, ISO, and other styles
46

Kilsby, Nadine N. "Reach-scale spatial hydraulic diversity in lowland rivers: characterisation, measurement and significance for fish." Thesis, 2008. http://hdl.handle.net/2440/49904.

Full text
Abstract:
Hydraulic conditions (velocity, depth, turbulence) strongly influence the distribution and abundance of organisms in rivers. A diverse hydraulic environment should foster biodiversity, because organisms have different hydraulic preferences. In fact, the relationship between spatial hydraulic diversity and biodiversity is largely presumed, and not well-supported by empirical studies, but it underpins efforts in river restoration and conservation. This is particularly so at the reach scale, indicating a stream- or river-section with large-scale homogeneous geomorphic and hydrological conditions and smaller-scale habitat patches, as perceived by organisms in the community under study. This thesis considers the factors that create spatial hydraulic diversity, and the ways that fish respond. It presents a method to characterise hydraulic diversity, and uses this to describe temporal and spatial changes between reaches. It also demonstrates the use of hydraulic modelling for comparing reaches. Finally, it assesses the Acoustic Doppler Current Profiler (ADCP) as a method to describe hydraulic conditions in a large, open river channel. Swimming ability tests were applied to three small freshwater fish, the pelagic Australian smelt (Retropinna semoni) and common galaxias (Galaxias maculatus ) and the demersal flathead gudgeon (Philypnodon grandiceps). The latter species was the weaker swimmer, but the tests indicated that behaviour also should be considered. A laboratory experiment was designed to investigate how two species with contrasting ecological habits (common galaxias, flathead gudgeon) behave in a diverse hydraulic environment. Habitat choices and activity were monitored in a constructed sinuous channel at three discharges over a 3-hour period. The galaxias favoured the pelagic habitat, and spent 20-60% of the time cruising, whereas the flathead gudgeon preferred the demersal habitat and spent <6% of the time cruising. The flathead gudgeons could access their preferred habitat at all discharges, but the common galaxias were limited by their swimming ability at the highest discharge. Several methods to characterise reaches were compared for eight 3-D model reaches representing the effects of channel form, wood and aquatic plants. The variogram (a measure of the variance between samples as a function of distance) emerged as a superior method because it indicates hydraulic diversity, incorporates the spatial arrangement of hydraulic patches, and facilitates comparisons between reaches. The ADCP proved a quick, reliable means to measure depth and 3-D velocity in rivers. It was effective only in depths >1.5 m, but modified instrumentation may overcome this limitation. Six reaches, including weir-pool and free-flowing sections, were compared at two discharges in the River Murray, Australia. Variograms derived from the ADCP data clearly demonstrated spatial differences between the sections, but temporal differences were less well-defined, suggesting that reaches may retain characteristic hydraulic patterns despite changes in discharge. Opportunities for further research include: the issue of optimal levels of hydraulic diversity for fish and other biota; use of variograms as a tool for field studies of aquatic biota; and measuring reach-scale hydraulic diversity and biodiversity before and after reach manipulation (e.g. the placement of wood), to elucidate the effects of changes in spatial hydraulic diversity on reach biodiversity.
Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2008
APA, Harvard, Vancouver, ISO, and other styles
47

"Community-based natural resource management, livelihood diversification & poverty alleviation : a case study of NG 22/23 and associated communities, Okavango Delta, northern Botswana." 2006. http://hdl.handle.net/10413/3453.

Full text
Abstract:
This paper presents a case study from Ngamiland, northern Botswana where community~ based natural resource management (CBNRM), through a joint venture agreement (NA) between a Community~based Organisation (CBO) and the private sector for nonconsumptive tourism has been implemented with the objective of contributing to localised poverty alleviation and livelihood diversification through employment and CBO fee revenue. The economic contribution of these benefits is considered with respect to commonly accepted norms and standards within the development ideology of sustainable development and its global measurements; therefore, a brief background of the concepts of poverty, livelihood and ecotourism is presented to provide context for the evaluation of CBNRM as a preferred land~use in Botswana. An evaluation of the significance of wage employment revenue and consequent remittances in the specific case study is intended to contribute to existing studies which have primarily emphasised the contribution of CBO fee revenue only to households. It is concluded that wage employment revenue makes a significant contribution at a household level to localised poverty alleviation and livelihood diversification compared to the insignificant contribution ofCBO fee revenue.
Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
APA, Harvard, Vancouver, ISO, and other styles
48

Harrison, Phillipa Anne. "The role of tourism in natural resource management in the Okavango Delta, Botswana." 2006. http://hdl.handle.net/10413/3427.

Full text
Abstract:
In recent years the use of tourism as a development strategy by Third World governments has increased, resulting in the intersection of international tourism and local resource utilisation patterns. The aim of this thesis is to critically assess the impact of tourism in the utilisation and management of natural resources in the Okavango Delta in Botswana. More specifically, the study appraises the current state of tourism and natural resource utilisation and management in the Okavango Delta; assesses the past and present forms of resource utilisation practised by the local inhabitants scattered throughout the Delta area; focuses on the implementation of government policy regarding resource use; highlights past and present relationships between tourism and resource utilisation; and examines the impact of tourism on the areas resources, environment and local inhabitants. Research has shown that the Okavango Delta, which is Botswana's primary tourism area, is faced with a number of social, economic and environmental challenges. These include extreme levels of poverty, especially in the rural areas; lack of infrastructure; competition over land and resources; growing regional inequality; social degradation; increased imports leading to foreign exchange leakages; changes in subsistence strategies and increased 'rural-urban' .migration; and the loss of control of the region by the local population to the global tourism system. The Okavango Delta is in the process of undergoing a change from traditional, rural, subsistence economies and livelihoods to capitalist, commercial-driven economic structures. In the Okavango Delta, as in many places around the world, people are in the process of being integrated into national level political, social and economic institutions, both within and outside of their control. The creation of employment for the local population, the sustainable use of the Delta and its resources, the development of the local agricultural industry, the continued growth of the tourism industry, and striking a balance between the conservation/preservation of the Okavango and meeting the water requirement needs of Angola, Namibia, and Botswana's growing populations are amongst the key concerns present in the area. 11 Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities. amongst the key concerns present in the area. Tourism in the Okavango Delta is directly dependent upon the utilisation of the region's natural resources of wildlife, water and natural vegetation areas for the industry. As such, tourism has increasingly impacted upon the way, and degree to which, these resources are managed and utilised, hence being identified as a key factor effecting the resource sector. If the Government of Botswana is to develop a tourism industry which fosters environmental and natural resource preservation, rather than maintaining a heavy dependence on limited and fragile resources, a better understanding of the relationship between the two sectors is necessary. Enhancing the positive linkages between tourism and natural resource utilisation in the Okavango Delta region represents an important means to stimulate increased natural resource and environmental protection, and improve the distribution of tourism benefits to rural communities.
Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006
APA, Harvard, Vancouver, ISO, and other styles
49

Mpondori, Priscilla Fungai. "Green logistics practices in Botswana : challenges and prospects for the large construction companies." Diss., 2020. http://hdl.handle.net/10500/27362.

Full text
Abstract:
The construction industry is generally characterised by limited implementation of green logistics. With that in mind, this study aimed to examine the nature and extent of green logistics practices in large construction companies in Botswana. Although empirical studies have analysed green supply chain in the construction industry, most of them have not addressed the challenges and prospects of adopting green logistics by construction companies in a developing country like Botswana. Project Managers were interviewed after which a thematic analysis was used to interpret the qualitative results. Thereafter, a comparative analysis was done between the results obtained from the interviews and from extant literature. The findings showed that the adoption of the green logistics strategies was aligned more to economic reasons than environmental ones. The findings further showed that until and unless the construction, technical and administration issues are addressed, the adoption of green logistics will continue to be a challenge for the construction industry in Botswana
Centre for Transport Economics, Logistics and Tourism
M. Com. (Logistics)
APA, Harvard, Vancouver, ISO, and other styles
50

Njiru, Lincoln Mwaniki. "Understanding the effects of a protected area on livelihoods of a neighbouring local community : a case study of Mokolodi Nature Reserve, Botswana." Thesis, 2007. http://hdl.handle.net/10413/1019.

Full text
Abstract:
Establishment of protected areas continues to be recognized in many parts of the world as one of the most appropriate strategies of conserving biodiversity. As a result, their numbers have continued to increase globally with significant support coming from many national governments and international agencies. Some cases of earlier establishments of protected areas had negative effects on local communities especially where there was displacement and relocation of people, and loss of access to various natural resources important for livelihoods sustenance. In other cases however, protected areas brought positive effects to local communities such as creation of employment opportunities, contribution towards community development and giving the local people the opportunity to actively participate in natural resources management. All these effects have influenced livelihoods of many local communities in several ways. This study focuses on the effects of Mokolodi Nature Reserve on a neighbouring community from the angle of a community that traditionally did not have exclusive access and use of the land that is now the reserve, nor have a claim against it. Effects of the changes that have occurred on the livelihoods of the local people since the establishment of the reserve are looked at, as well as the attitudes and perceptions that people have towards the reserve. Relationships between the reserve management and the local people that have brought changes in the lives of the local people form a key component of this study. Further, ways in which the local people are involved in natural resource management in the area are explored, as well as the reserve‟s contribution towards enhancing better and sustainable livelihoods of the local people The study adopts a qualitative approach, with information being collected by use of structured questionnaires and key informant interviews. The majority of respondents were members of the local community. A few key informants were from outside the community but had associations with the area of study. Data was analyzed and presented in the form of descriptions, tables and graphs. Findings show that the reserve has brought changes, some of which have benefited the local community such as provision of job opportunities and creation of environmental awareness among the people. However, according to some respondents, especially the older, such benefits are minimal and only go to a few people. Such respondents hence consider the reserve to be of little or no benefit to the community. Attitudes and perceptions towards the reserve vary amongst respondents, with younger respondents appearing to have more positive attitudes and perceptions towards the reserve. Indications are that the relationship between the reserve management and the local community is not very well developed. The older respondents however appear to be keen on having good relationships with the reserve management established, as opposed to many of the younger respondents whose main concern is employment. Lack of community conservation initiatives in the area is considered a drawback towards increased people‟s participation in resource management in the area. Despite the varied opinions in terms of benefits and non-benefits, the reserve would still be considered to have played an important role in improving the livelihoods of the local people. Indications that some people have an interest in getting involved in various reserve-related activities, is a good opportunity for developing good relationships. This could also possibly change the negative attitudes and perception some people have towards the reserve. With continued interactions and learning of lessons from the past, there are opportunities for the reserve management and the local people to work together and hence find a balance between conservation priorities and local livelihoods. This would also work towards achieving one of the initial goals of the establishment of the reserve, of improving the standards of living of people in the local community.
Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography