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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Optimal ways to harvest and purify rainwater in the Western and Nyanza provinces, Kenya

Odevik, Anders, Nordström, Christian January 2010 (has links)
<p>The access to water in the regions around Lake Victoria varies with the rainy seasons. Today the daily labor of fetching water is a heavy burden for people in the rural areas. In the process of this study farmers in the Western and Nyanza provinces in Kenya are interviewed, water samples are analysed and present rainwater harvesting techniques and purification methods are observed. As a result, suitable solutions to the problems found are discussed. An optimal system is chosen for the region with a concept selection matrix. An elaborated dimensioning tool for roof and purpose-built harvesting systems is developed. Finally a summarized manual is attached in order to raise interest for rainwater harvesting among the farmers that the non-governmental organisation SCC-Vi Agroforestry cooperates with.</p> / <p>Tillgången till vatten i områdena kring Victoriasjön varierar med regnperioderna. Det dagliga arbetet med att hämta vatten är idag en stor börda för människor på landsbygden. Under processen av denna studie intervjuas bönder i Western och Nyanza provinserna i Kenya, vattenprover analyseras och nuvarande regnvatteninsamlingstekniker och reningsmetoder observeras. Som ett resultat diskuteras passande lösningar på de problem som hittats. Ett optimalt val av komplett system för regionerna tas fram med hjälp av en konceptvalsmatris. Ett genomarbetat verktyg för dimensionering av tak- och ändamålsbyggda insamlingssystem utvecklas. Slutligen inkluderas en sammanfattande manual för att väcka intresse för regnvatteninsamling bland de bönder som den ideella organisationen SCC-Vi Agroforestry samarbetar med.</p>
92

Coupled Hydrological and Microbiological Processes Controlling Denitrification in Constructed Wetlands

Kjellin, Johan January 2007 (has links)
<p>Treatment wetlands play an important role in reducing nitrogen content in wastewater and agricultural run-off water. The main removal process is denitrification and the removal efficiency depends on the hydrological and microbiological features of the wetland, especially in terms of water residence times and denitrification rates. The aim of this thesis was to increase the understanding of the coupled hydrological and microbiological processes regulating the denitrification capacity. This was done by applying a broad spectrum of analyses methods, including tracer experiment, water flow modeling, denitrification rate measurements, and analyses of the microbial community structures. The tracer experiment and flow modeling revealed that the wetland design, especially the vegetation, largely can affect the water residence time distributions in wetlands. In the investigated wetland, vegetation dominated the water flow, explaining 60-80% of the variance in water residence times, whereas basin shape only explained about 10% of the variance, but also mixing phenomena significantly affected the residence times and could considerably delay solutes. Measured potential denitrification rates in the wetland exhibited significant spatial variations, and the variations were best described by concentration of nitrogen in sediments and water residence time. Analyses of the denitrifying bacteria populations indicated that a few key populations dominated and that the community diversity increased with decreasing nutrient levels and increasing water residence times. Moreover, it was found that denitrification rates in terms of Menten and first order kinetics can be evaluated by fitting a mathematical expression, considering denitrification and other nitrogen transforming processes to measured product formation in nitrate limited experiments.</p>
93

Application of indigenous materials in drinking water treatment

Kalibbala, Herbert Mpagi January 2007 (has links)
<p>Volcanic ash and Moringa oleifera (M. oleifera) were investigated as indigenous materials for drinking water treatment based on problems identified at Kampala and Masaka water treatment plants in Uganda. Coagulation experiments were done using swamp raw water at Masaka National Water & Sewerage Corporation water treatment plant and pilot-scale filtration experiments carried out at Ggaba II (Kampala) water treatment plant. The results from the study indicated that there were both operational and design handicaps at the treatment plants in Kampala. There is need to modify the filtration and clarification units to enable production of water meeting both the national and international standards. At Masaka water treatment, there was increase in trihalomethanes concentration as a result of pre-chlorination. Following aeration and pre-chlorination processes, the average increase of total trihalomethanes concentration was over 4000% with over 99% being chloroform. Preliminary results from the jar test experiments indicated that use of alum with MOCSC as coagulant aid is promising as a first stage in the treatment train for waters with a humic materials and high content of iron, typical of swamp water sources. This would probably eliminate the formation of unwanted by-products by eliminating the pre-chlorination process. Assessment of the characteristics of the volcanic ash showed that it meets the requirements for a filtration material; and results obtained from the pilot study showed that it was a suitable alternative material for use in a dual media filtration system. There was an increase in the filter run length of about two and half fold in the dual media filtration column compared to the mono medium column. Both columns produced similar water quality levels. Therefore, conversion of the rapid sand filters at Ggaba and similar water treatment plants in the country to dual media (volcanic ash on top of sand) systems would probably significantly improve the performance of the filtration systems.</p>
94

Wetland Conversion to large-scale agricultural production; implications on the livelihoods of rural communities, Yala Swamp, Lake Victoria basin, Kenya.

Kinaro, Zachary January 2008 (has links)
<p>Wetlands in most parts of the world are under threat of over-exploitation, loss and/or degradation partly due to agriculture and urban land uses.</p><p>Yala swamp, the largest fresh water wetland in Kenya measuring about 17,500 ha supports a large biodiversity and is source of livelihoods to communities around it. This study addresses the situation where part of this wetland is converted into large-scale agriculture by a multinational company, Dominion Farms (K) Ltd resulting into a conflict and controversy amongst key stakeholders. The study sought to investigate livelihood impacts this transformation has for the local community. It employs the concepts Stakeholder Analysis (SA) and Sustainable Livelihood Approaches (SLA) to asses the livelihood situation in terms of socio-economic conditions, rural infrastructure, income diversification, food security and environmental issues.</p><p>Data and information have been obtained from primary and secondary sources through field survey at the Yala wetland, in which randomly sampled small-scale farmers, fisher folk, Dominion employees, local leaders and informants, traders and other stakeholders were interviewed using questionnaire and other participatory methods. The main questions were designed to gain information about historical use of the wetland, changes in livelihoods and wetland before and after entry of Dominion Company into the area. From the study, it is evident that assessment of the key stakeholders in relation to this natural resource is of utmost importance for mapping out an acceptable management strategy for the wetland. Besides being cause to a conflict and controversy over control of and access to the swamp, the conversion has resulted into both negative and positive short-term and long-term livelihood impacts to the local community. The wetland being a contested resource with multiple users who claim a stake on it requires a holistic approach in its management that caters for divergent needs and views of key stakeholder groups. The study identifies management issues and proposes abroad vision for the future including recommendations for planning as well as suggestions for specific research needs that should form the basis of action</p>
95

Wetland Conversion to large-scale agricultural production; implications on the livelihoods of rural communities, Yala Swamp, Lake Victoria basin, Kenya.

Kinaro, Zachary January 2008 (has links)
<p>ABSTRACT</p><p>Wetlands in most parts of the world are under threat of over-exploitation, loss and/or degradation partly due to agriculture and urban land uses.</p><p>Yala swamp, the largest fresh water wetland in Kenya measuring about 17,500 ha supports a large biodiversity and is source of livelihoods to communities around it. This study addresses the situation where part of this wetland is converted into large-scale agriculture by a multinational company, Dominion Farms (K) Ltd. The study was undertaken to investigate the livelihood impacts this transformation has for the local community. It employs the concepts Stakeholder Analysis (SA) and Sustainable Livelihood Approaches (SLA) to assess the livelihood situation in terms of the socio-economic status, rural infrastructure, income diversification, food security and environmental management issues.</p><p>Data and information have been obtained from primary and secondary sources through field survey in the Yala wetland, in which randomly sampled small-scale farmers, fisher folk, Dominion employees, local leaders and informants, traders and other stakeholders were interviewed using questionnaire and other participatory methods. From the study, it is evident that assessment of the key stakeholders and their relation to this natural resource is of utmost importance for mapping out an acceptable management strategy for the wetland. Besides being cause to a conflict and controversy over control of and access to the swamp, the conversion has resulted into negative and positive short-term and long-term livelihood impacts to the local community. This contested resource with multiple users who claim a stake on it requires a holistic approach in its management that caters for divergent needs and views of key stakeholder groups. The study identifies management issues and proposes abroad vision for the future including recommendations for planning and research needs that should form the basis of action.</p>
96

Föroreningen av Östersjöns vatten : Enskilda avlopp och åtgärder för en långsiktig uthållig vattenanvändning / The pollution of the Baltic sea : Private drains and actions for a long-term water use

Holmer, Erik January 2008 (has links)
<p>I denna uppsats undersöks det hur det fungerar med enskilda avlopp utanför kommunens VA-nät. Hur enskilda avlopp är uppbyggda och hur de fungerar. Varför man bör ha avloppsrening, och vilka lagar och regler som styr enskilda avlopp. Jag utreder vidare varför man ska jobba för en ökad rening av avlopp och varför man ska jobba mot att uppnå ett uthålligt samhälle.</p><p>Uppsatsen har en teoridel som handlar om hur och varför vi ska sträva efter en uthållig samhällsutveckling. En strävan som kommuner som Söderköping har när dom försöker få människor att byta till hållbara VA-system.</p><p>Med dom här funderingarna som bakgrund och ett antal frågeställningar har jag skrivit en fyllig bakgrund som går igenom Östersjöns problematik och även relevant information om enskilda avlopp. Jag går igenom varför vi behöver en bra rening och hur man kan jobba för att uppnå en bättre rening. Bakgrunden ger en grund för att jag ska kunna genomföra min undersökning på ett bra sätt.</p><p>I resultat delen undersöker jag hur Söderköpings kommun och Allren arbetar med enskilda avlopp. Jag valde Söderköpings kommun för att det är en kustnära kommun som av den anledningen alltid brottas med att inte få ut läckage av näring i Östersjön. Och det märks att dom har tagit detta ämne på allvar då dom jobbar för att skapa recirkulation av näringen genom exempelvis urinsorterande system.</p><p>I slutet av uppsatsen har jag diskussions delar där jag flätar samman uppsatsen och för en diskussion om vad jag har kommit fram till och vad jag har för åsikter om arbetet med enskilda avlopp.</p><p>Uppsatsen avslutas med att jag har med en didaktik del. En didaktisk del som gör det möjligt att lära ut de kunskaper man besitter efter en uppsats.</p>
97

Reliability of Payment for water Resources as an Environmental Service towards the sustainable management of watershed forests in Zanzibar, Tanzania : A Case study of Kiwengwa - Pongwe Forest Reserve

Hussein Hassan, Iddi January 2007 (has links)
<p>Currently, there is a great rampage among conservationists looking for useful approaches that can be used to bring efficiency towards conservation of global natural ecosystems. But which approach can be really effective to halt destruction of a particular natural ecosystem where the local people depend on the same ecosystem resources for their livelihoods? Do the local communities accept to refrain themselves from using natural ecosystem resources (loss of free access), which they believe is under their local territory since they are born, without having alternatives that will replace and improve economic gain of their livelihoods? Are the consumers who benefited from the ecosystem services always willing to compensate local communities around natural ecosystem as a means of replacing what they lose?</p><p>This study looks at the reliability of Payment for Water Environmental Services (PWES) approach at Kiwengwa-Pongwe Forest Reserve (KPFR) as a device aimed at promoting the sustainable management of KPFR watershed resources without undermining livelihoods of the Kiwengwa-Pongwe local communities. Hoteliers along the Kiwengwa-Pongwe Tourist Area (KPTA) are the potential customers benefiting from water resources found in the KPFR, which is claimed to be deteriorated by the intensity of the livelihood activities of Kiwengwa-Pongwe (KP) local communities. Based on Contingent Valuation Method (CVM), KPTA hoteliers were asked about the amount they would be willing to pay as maximum (WTP) for improvement of water services through sustainable management of watershed areas in KPFR. On the other hand, KP communities were asked what level of compensation they would be willing to accept as minimum amount (WTA) for a loss of free access to KPFR.</p><p>Both hoteliers (75 %) and KP communities (91 %) agreed on the establishment of the PWES system. However, there were differences between amount accepted by KP communities (10 US$ per 200 litres) and the amount claimed to be paid by hoteliers (1US$ per 200 litres), thus giving a gap of 9US$. Based on the overall study findings and experiences from other parts of the world where similar systems have been implemented, this issue is negotiable. It is upon existing KPFR management team and proposed board from Zanzibar water authority to launch a constructive dialogue between stakeholders to reach the amount that can be used as compensation causing no harm to both parts and without compromising the sustainable management of KPFR.</p>
98

Expanding Water Service Delivery through Partnership between Water Utility and Small Scale Water Providers in Lusaka, Zambia : A Case of Lusaka's Peri-Urban Areas

Mwandu Siyeni, Yvonne January 2008 (has links)
<p>Zambia is a highly urbanized country with 60% of its urban population residing in low cost areas also called peri-urban, slum or informal settlements. The increase in urban population attributed to rapid migration and urbanization due to political and economic changes has taken a toll on service provision as the infrastructure development and service provision has failed to meet the demand. For the 33 peri-urban areas in Lusaka, the water supply and sanitation has been poor, inadequate and unreliable with the coverage being slightly above 50% for water while 90% of the urban population does not have access to the much needed sanitation. The low coverage is a result of lack the financial capacity on the part of the service providers to extend services to un served areas.</p><p>This research focuses on the strategies to provide sustainable water and sanitation services to peri-urban areas to ensure improved accessibility through the expansion of infrastructure and attainment of full cost recovery. In this era of increasing migration to unplanned settlements where the services are inadequate, alternatives to public provision of water and sanitation services need to be put in place. One of the alternatives is the public-private partnership which encompasses the society, private and the civil society. As has been found in the study the best alternative should not only be completely bottom up but should also be more demand driven and be able to provide for reater contributions from the affected communities.</p><p>The hypothesis of the study is to ascertain if provision of water supply to the Peri-Urban Areas (PUAs) can be achieved through the partnership between the water utility and the small scale water providers. Therefore, the objectives of the research are to: evaluate and compare the current service provision to the peri-urban areas by the utility and small scale providers in terms of technical, social and institutional arrangements and determine the best way of ensuring sustained service provision to peri urban areas and show how partnership can be the best solution to improving service delivery to these areas.</p><p>Service provision in PUAs can not be achieved without the involvement of all the stakeholders especially the community who are also the users and whose major role is paying for the service to enhance sustainability. In this study the Small Scale Water Providers (SSWP) users were found to be satisfied with the service provided than the utility users who felt that more needed to be done. The two providers are found to have different strengths which when combined would enhance service provision. The collaboration between utility with its competence in water supply, technical installations, water quality testing and SSWP with theirs in community involvement, cost recovery, effective operation and maintenance and demand driven water schemes have to be merged to achieve the intended goal and it is also an indication that the two can complement each other. Utility should therefore consider opening investment accounts for all the areas so as to detach PUAs needs from the general plan and eventually budget as they would be self sustaining and enhance  illingness to pay for the users. The SSWP should therefore be viewed as partners by all and licensing should be considered by the government for the benefit of the urban poor.</p>
99

Expanding Water Service Delivery through Partnership between Water Utility and Small Scale Water Providers in Lusaka, Zambia : A Case of Lusaka’s Peri-Urban Areas

Mwandu Siyeni, Yvonne January 2008 (has links)
<p>Zambia is a highly urbanized country with 60% of its urban population residing in low cost areas also called peri-urban, slum or informal settlements. The increase in urban population attributed to rapid migration and urbanization due to political and economic changes has taken a toll on service provision as the infrastructure development and service provision has failed to meet the demand. For the 33 peri-urban areas in Lusaka, the water supply and sanitation has been poor, inadequate and unreliable with the coverage being slightly above 50% for water while 90% of the urban population does not have access to the much needed sanitation. The low coverage is a result of lack the financial capacity on the part of the service providers to extend services to un served areas.</p><p>This research focuses on the strategies to provide sustainable water and sanitation services to peri-urban areas to ensure improved accessibility through the expansion of infrastructure and attainment of full cost recovery. In this era of increasing migration to unplanned settlements where the services are inadequate, alternatives to public provision of water and sanitation services need to be put in place. One of the alternatives is the public-private partnership which encompasses the society, private and the civil society. As has been found in the study the best alternative should not only be completely bottom up but should also be more demand driven and be able to provide for greater contributions from the affected communities.</p><p>The hypothesis of the study is to ascertain if provision of water supply to the Peri-Urban Areas (PUAs) can be achieved through the partnership between the water utility and the small scale water providers. Therefore, the objectives of the research are to: evaluate and compare the current service provision to the peri-urban areas by the utility and small scale providers in terms of technical, social and institutional arrangements and determine the best way of ensuring sustained service provision to peri urban areas and show how partnership can be the best solution to improving service delivery to these areas.</p><p>Service provision in PUAs can not be achieved without the involvement of all the stakeholders especially the community who are also the users and whose major role is paying for the service to enhance sustainability. In this study the Small Scale Water Providers (SSWP) users were found to be satisfied with the service provided than the utility users who felt that more needed to be done. The two providers are found to have different strengths which when combined would enhance service provision. The collaboration between utility with its competence in water supply, technical installations, water quality testing and SSWP with theirs in community involvement, cost recovery, effective operation and maintenance and demand driven water schemes have to be merged to achieve the intended goal and it is also an indication that the two can complement each other. Utility should therefore consider opening investment accounts for all the areas so as to detach PUAs needs from the general plan and eventually budget as they would be self sustaining and enhance willingness to pay for the users. The SSWP should therefore be viewed as partners by all and licensing should be considered by the government for the benefit of the urban poor.</p>
100

Why states cooperate over shared water: The water negotiations in the Jordan River Basin

Jägerskog, Anders January 2003 (has links)
The focus of this thesis is on foreign-policy decision-making in circumstances of water scarcity. In particular the study focuses on how the issue of water has been treated in the interstate negotiations within the Peace Process between Israel and the Palestinians and Israel and Jordan. It also analyses the implementation phase. The aim of this study is to analyse why and under what conditions co-operation has taken place and how it has functioned in the water sector. As such the study moves beyond the vast quantitative material which states that transboundary water co-operation does occur by exploring why co-operation has occurred in the Jordan River Basin. Based on an overall actor-structure framework the factors deemed to be important in affecting the process and outcome are identified. The development of a shared system of norms, rules and procedures for how to manage the water resource are seen as a vital explanatory variable for the water co-operation in the Jordan River Basin. It is concluded that the water negotiations, both between Israel and the Palestinians and between Israel and Jordan have been intimately linked to the other issues on the negotiation table. Further-more, it is concluded that water has been sub-ordinate to other politically more salient questions in the negotiations. The thesis contributes to the body of research on water in the Jordan River Basin in three ways. First, it provides and empirical overview of the implementation process of the water elements of the Peace Treaty between Israel and Jordan and of article 40 (which deals with water) of the Interim Agreement between Israel and the Palestinians. Second, the thesis has analysed the role that scientific experts play in the water negotiations. Expert advice has been used in the negotiations and can be said to be important in that it reduces uncertainty for decision-makers as well as provide tools with which to legitimise political decisions. Third, the thesis contributes to the understanding of why the parties in the Jordan River Basin have chosen co-operative strategies rather than resorting to conflictual behaviour to handle their shared waters. Of key importance in this respect is that shared water is an interdependent resource. Thus mutual dependence on a shared resource stimulates and reinforces the need for cooperation.

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