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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.
21

Investigating the Social-Ecological Resilience of Water Management Practices within Ethnic Minority Hill Tribes of Northern Thailand

Vogt, Jason January 2007 (has links)
<p>Resilience is an essential and highly desired characteristic of a social-ecological system’s ability to adapt and adjust to various stresses and shocks that cause disruption. As social and ecological systems are intertwined and continually experiencing changes and disturbances, a major challenge appears revolving around the ways in which this resilience can be built and investigated. Social-ecological resilience can be defined as the amount of stress or disturbance that a particular system can tolerate, while still maintaining the same functions and identity. This paper uses social-ecological resilience concepts as a research framework, and examines three main themes that allow for the building of water management resilience to occur. These themes include learning to live with change, nurturing the ability to adapt/adjust to changes, and also on creating opportunities for self-organization. Two ethnic minority villages in Northern Thailand were chosen as research sites, in which the village water management practices were studied within a specific time period. Varying degrees of quantity and quality water issues within both villages have brought about stress and disturbances within their water management practices and increased the need to deal with these problems. Research was conducted at a community scale and resilience analysis pertains only to this specific level. Through the utilization of focus groups and interviews, qualitative data was collected and analyzed within a SE resilience context. This paper sets out to explore how social-ecological resilience has been built or not, and to what degree this has occurred within these two villages water management practices. The analysis indicates how complex and interconnected the social and ecological systems are and how the water management practices of these two communities play a role in this complex, dynamic process. Conclusions drawn are not limited to these two communities, but can be applied to the wider Northern Thailand region.</p>
22

Water resources development: opportunities for increased agricultural production in Nigeria

Olagunju, Emmanuel Gbenga January 2007 (has links)
<p>Agriculture has been the backbone of the economy in Nigeria providing employment and source of livelihood for the increasing population and accounting for over half of the GDP of the Nigeria economy at independence in 1960. However, the role it plays in the regional and economic development of the country has diminished over the years due to the dominant role of the crude oil sector in the economy. With the increasing food demand in Nigeria, the country has available input natural resources and potential for increasing the volume of crop production towards meeting the food and nutritional requirement of the rapidly increasing population and guarantee food security in the country. The study was undertaken to analyse the effect of different factors and policies on the changes in trend of crop production and investigate the possible effect of water resources development on increased volume of agricultural crop production in Nigeria.</p><p>The study revealed that there are opportunities for water resources development in the country through irrigation to supplement the water requirements and needs of farmers for agricultural production activities in many areas in the semi-arid and arid regions. Available data shows that there are available land and water resources that could be developed to support the production of food and agricultural development with opportunity for increased productivity.</p><p>However, while the water resources are unevenly distributed in the country, there is need for the efficient use and management of the available water resources and increasing the productive use especially in the northern region of the country where there is increasing incidence of drought and competing need for water among the different sectors of the economy. The study also made possible recommendations for policy formulation to address the current problems facing the agricultural sector in conjunction with the requirement for the development of the water resources.</p>
23

Managing agricultural nutrient leaching within the EC Water Framework Directive in Sweden

Bratt, Anna-Lena January 2003 (has links)
Agricultural management practices geared towards reducing nutrient leaching are in focus for the research presented in this thesis. Critical measures for reducing diffuse pollution from the agricultural sector depend on decisions of individual farmers. It is useful to take stock of what different stakeholders are actually doing to reduce nutrient leaching and analyze their reasoning before defining a new administrative process. Stakeholder perceptions about potentials and problems concerning management of agricultural practices are analyzed with a systems approach using various analytical methods, and put in relation to the implementation of EC Water Framework Directive in Sweden. The methods used include surveys, focus group interviews, model comparison, sensitivity analyses and analyses of climate change implications. The results indicate a general positive attitude among stakeholders towards the main characteristics of the newly introduced directive. They also reveal that a move towards a pro-active process was perceived as an additional positive factor for the improvement of water quality, where specific activities and measures are carried out according to planning based on local assessments. The respondents pointed out that a national approach would put necessary pressure on local politicians to define environmental objectives and provide resources to fulfil them. The current findings indicate that decision making for farmers is a complex procedure and that the different factors need to be addressed in order to obtain a change in agricultural practices. Consistent legislation that is clear about power and rights is fundamental for cooperation to function when volunteerism and enthusiasm are absent. Environmental and socio-economic conditions change constantly, and administration has to be flexible to be able to adapt. Having access to and being able to use relevant data is only one important factor for stakeholder involvement. To give farmers the opportunity to further develop production towards reduced nutrient losses, appropriate information provided in all the right arenas is crucial.
24

Forests and Greenhouse gases. Fluxes of CO2, CH4 and N2O from drained forests on organic soils

Arnold, Karin von January 2004 (has links)
One of the largest environmental threats believed to be facing us today is global warming due to the accumulation of green house gases (GHG). The concentrations of GHG in the atmosphere are a result of the net strength of different sinks and sources. Forests, in this context, are of particular interest because of their dual role as both sinks and sources. Most forests are net sinks for CO2 but others, such as drained forests, may be significant sources of both CO2 and N20. Consequently, it is essential to understand the fluxes of GHG between drained forests and the atmosphere in order to obtain accurate estimates of national GHG budgets. The findings reported in this thesis and the accompanying papers are based on dark chamber flux measurements of soil GHG fluxes and modelled annual net primary productions in five drained forest sites and two undrained sites situated on organic soil. Temporal variations in forest floor CO2, release could be explained, to a large extent, by differencies in temperature and groundwater level. The within-site spatial variation in soil GHG fluxes could only be explained to a very small extent by distance to tree stems. Much of the among-site variations in soil CO2 and CH4 release could be caused by differences in the mean annual groundwater table, while N20 emissions were strongly correlated to the carbon-to-nitrogen ratio of soil organic matter. Most poorly drained forested areas are probably net sinks for GHG as the CO2 uptake by trees more than compensates for the soil GHG emissions. However, the total drained forested area in Sweden was estimated to be a net source of GHG. The CO2 release from decomposition of soil organic matter stored before drainage was estimated to be substantial. Corresponding to 15% of the CO2 release from the consumption of fossil fuels. / <p>On the day of the public defence of the doctoral thesis the status of the articles I and II was: Conditionally accepted; article III was: Submitted and articles IV and V was: Manuscript. The title of article III was on the day of the public defence "Can the distribution of trees explain the spatial variation in N2O emissions from boreal forest soils?".</p>
25

Urban Water Security – Local Conditions and Regional Context : A case study of attitudes and water use behaviour in Windhoek, Namibia

Sjömander Magnusson, Therése January 2005 (has links)
The world is becoming urbanised. Between 1995 and 2025, it is estimated that the cities and towns of the developing world will have absorbed another two billion people. A majority of these people will be poor and settle down in the unregulated areas. It is therefore fair to say that the management and use of water in urban areas is a very complex and dynamic issue. The fact that cities in the South are composed of two systems, the regulated and the unregulated areas, and that considerable diversity exists between them, highlights the need for a context driven policy design in urban water management. For attaining urban water security in these cities, controlling water demand in the regulated areas while improving access to water of good quality in the unregulated areas must be a priority. This thesis is based on a case study of Windhoek, a city characterized by conditions of aridity, rapid urbanisation and primate city dominance. Since 1994, a thorough water demand management (WDM) strategy has been implemented in Windhoek, aiming at improving water use efficiency and to reduce water consumption through economic and non-economical measures. It has been the purpose to examine the development of urban water management along with urban growth, the response to WDM by the domestic and private business sectors, as well as challenges and benefits of allowing urban branch-lines along water transfer schemes. WDM can be an efficient tool in the struggle against luxury and non-efficient water use, to postpone bulk water investments and for cost-recovery. However, it is crucial that the incentives are based on and flexible according to socio-economic conditions, and that water managers acknowledge motives and attitudes that shape water use behaviour. One dilemma of WDM lies in the fact that if the supply capacity is increased, it is likely that demand will be adjusted accordingly. It is a tricky task to motivate water savings through demand management alongside with an improved water supply. Moreover, it is essential that savings are not only temporary, but also part of a long-term adjustment. Another predicament of WDM is that a high trust in water authorities actually lowered the efficiency of the strategy to meet the anticipated goal.
26

Views of Nature and Environmental Concern in Iceland

Árnason, Þorvardur January 2005 (has links)
Environmental concern in contemporary societies is a complex phenomenon which is shaped and influenced by a host of different factors. One of the most important of these is the interplay between culture and nature that has taken place during the course of a nation’s history and the various ‛views of nature’ that such interplay has generated. Such views can e.g. manifest themselves in aesthetic judgments of natural scenery or, more generally, in the values that nature is seen to contain or carry. They form the base from which contemporary ideas, conceptions, and evaluations of nature are generated and debated. The five studies that together comprise this thesis explore the socio-cultural background of Icelandic environmentalism from a number of different perspectives. The first study concerns the depiction(s) of nature that can be found in the oldest literary works that have survived in Iceland. The second study deals with the first attempts by an Icelander to visualize nature in his homeland, using photographic media. The third study seeks to compare contemporary views of nature amongst Icelanders, e.g. concerning the appreciation of natural beauty, with those of Swedes and Danes. The fourth study reports the results of an extensive survey which probed the environmental values, knowledge, attitudes and behaviors of present day Icelanders. The fifth study builds on this same survey but focuses on the public understanding and perceptions of sustainable development, and also on the connections between attitudes toward environmental and developmental issues. This overall thesis project was multi-disciplinary in nature, combining theory drawn from environmental philosophy, especially ethics and aesthetics, with the theories and methods of environmental sociology, politics and history. The empirical studies employed, furthermore sought to operationalize certain key theoretical constructs relating to views of nature, such as environmental value orientations and aesthetic appreciation of nature, and thus ‛build bridges’ between the concerns, theories and methods of the humanities, on one side, and those of the social sciences, on the other.
27

Monitoring transport and fate of de-icing salt in the roadside environment : Modelling and field measurements

Lundmark, Annika January 2008 (has links)
Roads and traffic are a major non-point source of pollutants and may have severe impacts on surface water, groundwater, soil and vegetation. In cold climates, de-icing salt is one such pollutant that may cause increased chloride concentrations and induce other effects on the environment. Monitoring and quantifying environmental effects are crucial for governing decisions towards more suitable use of de-icing salt in order to achieve and maintain good environmental status around roads. This thesis presents an operational modelling tool for monitoring the transport and fate of de-icing salt in the roadside environment in order to quantify changes in the environment at various spatial and temporal scales, using salt application data, meteorological data, geology and generic descriptions of hydrogeological environments as main inputs. A combination of modelling and various independent field measurements provided an efficient means for evaluating and describing the spread of de-icing salt from the road to the surroundings, the deposition of salt and ploughed snow in the roadside, and the corresponding increase in chloride concentration in soil and groundwater. Both the spatial and seasonal variation in soil chloride concentration were significantly affected by de-icing salt application. The importance of type of soil, vegetation type, groundwater conditions and distance from the road was clearly demonstrated for modelling the transport and fate of de-icing salt in the roadside environment. Salt emissions from the road by surface runoff were estimated at 50-80% of applied salt and transport by snow ploughing and air emissions at 20-50%. The uncertainty in the spatial distribution of snow and salt deposition close to the road was high and a previous proposed exponential decline in salt deposition with distance from the road could not be justified within a couple of metres from the road. Future monitoring should include both modelling and systematic data collection in order to reduce the uncertainty in predictions of the environmental impact of de-icing salt. Modelling of chloride concentration, soil water content and soil temperature and measurements of electrical resistivity may be a cost-effective solution for quantifying changes in the roadside environment. / QC 20100526
28

Access to water : Rights, obligations and the Bangalore situation / Tillgång till vatten : Rättigheter, skyldigheter och situationen i Bangalore

Grönwall, Jenny T. January 2008 (has links)
The city of Bangalore in southern India is undergoing rapid urbanisation and administrative transition. Its growth puts pressure on the available water sources – being mainly the disputed inter-State River Cauvery and the hard-rock aquifers – with ensuing problems of access. These aspects affect how rights to and over water are fulfilled and perceived. Competition for drinking water is intensifying worldwide and over a billion people are estimated to lack safe access to it. Urbanisation and other demographic trends, along with globalisation and climate change, are adding to the changing patterns of water scarcity. The role of rights in attaining and improving access to water is undoubtedly great and often referred to in the general water management debate. The notion is analysed here as having three interlinked dimensions: the right to water as a human right; water in terms of property rights; and water rights. Law treats these rights, and thereby water, differently. For instance, groundwater has traditionally been thought of as invisible and unpredictable. Partly for this reason, it is still left largely unregulated in many parts of the world. In India, according to the proverb, ‘the landlord is a water lord’. This has effects on the claim for water as a human right. The dissertation shows that we cannot talk in terms of water and rights until we are aware of how complex rights apply simultaneously, and how they correspond to obligations.
29

Chlorine Transport in a Small Catchment

Svensson, Teresia January 2006 (has links)
De senaste decenniernas forskning har påvisat att en omfattande bildning och nedbrytning av klororganiska föreningar sker i mark. Bildning av sådana föreningar sker genom att klorid binds in i organiskt material. Denna naturliga bildning har rönt uppmärksamhet dels för att många klorerade ämnen är giftiga och dels för man tidigare trott att alla klororganiska ämnen uteslutande kommer från mänsklig verksamhet. Huvudmålet för föreliggande avhandling var att (i) uppskatta transporten av klorerade föreningar i nederbörd och avrinningsvatten, (ii) diskutera de klorerade föreningarnas ursprung med utgångspunkt från hur deras förekomst varierar i avrinningsvatten, (iii) undersöka hur transporten av klorid (salt) påverkas av olika faktorer och (iv) studera hur frisättningen av flyktiga klorerade föreningar från mark påverkas av kväve. Avhandlingen bygger på en klorbudget som konstruerats utifrån fältstudier som genomförts i ett litet skogsbeklätt avrinningsområde i sydöstra Sverige. Dessutom har laboratoriestudier genomförts med jord som inhämtats från samma område. Resultaten visar att lagret av klor i marken är betydligt större än flödena och att det främst består av organiska ämnen medan flödet domineras av klorid (salt). Detta tyder på att en stor del av kloriden deltar i en biogeokemisk cykel vilket strider mot gängse uppfattning att klorid rör sig opåverkat genom mark. Hypotesen är att de översta marklagren fungerar som en sänka för klorid genom att omvandlas till organiskt bundet klor. De djupare jordlagren fungerar däremot som en kloridkälla genom att det klorerade organiska materialet transporterats med regnvatten från de ytligare till de djupare liggande lagren för att så småningom brytas ner, varvid klorid frisätts. Ovan beskrivna hypotes stöds av laboratoriestudierna där man kunnat notera att det sker såväl en fastläggning som en frisättning av klorid i mark. Resultaten från avhandlingen tillsammans med resultat från tidigare studier tyder på att en stor del av den klorid som finns i avrinningsvatten kommer från förmultnande organiskt material och att klorid med andra ord inte följer regnvattnets väg genom marken, vilket man tidigare trott. Studierna tyder alltså på att klorid till viss del ”gör en omväg” med en tidsfördröjning på troligen åtskilliga upp till hundratals år. Vidare tyder studierna på att flyktiga klorerade föreningar som kloroform och tetraklormetan bildas i mark och att tillsats av kväve orsakar en minskning av kloroform och en ökning av tetraklormetan. Avhandlingen visar tydligt att det är nödvändigt att rikta uppmärksamhet mot klors biogeokemi i mark och då inte minst mot de processer som påverkar transporten av klor från de övre marklagren till grundvatten och ytvatten om vi ska öka förståelsen av hur klorerade ämnen som tillförts naturen genom mänskliga aktiviteter beter sig. / It is generally known that chlorine compounds are ubiquitous in the environment. In recent years, researchers have concluded that chlorine is part of a biogeochemical cycle in soil involving an interaction between chloride (Clin) and organic-matter-bound chlorine (Clorg). Even though there is indisputable evidence that Clorg is formed naturally, there are actually few simultaneous field measurements of Clorg and Clin. Previously stipulated conclusions with respect to underlying processes and transport estimates have thus been deduced from rather few concentration measurements. It is well known that the chemical composition in soil and runoff water varies widely over time and in space. The main objective of the thesis is to investigate the on-site variation of Clin, Clorg and VOCls in runoff water in order to (i) construct a chlorine budget on a catchment scale to visualize the relative contribution of Clin, Clorg, and VOCls; (ii) more reliably estimate how and why the concentrations of Clin, Clorg, and VOCls in runoff water vary; and (iii) analyze the influence of various environmental variables on the transport. The present thesis highlights the on-site variation and fluxes of Clin, Clorg, and VOCls in a small forested catchment in southeast Sweden. Field flux data collected during a twoyear period and a constructed overall chlorine budget were evaluated. The results show that the storage is dominated by Clorg whereas the transport is dominated by Clin and that the storage is far much larger than the transport. Still, input and output is nearly in balance for all investigated chlorine species. It is interesting to note that these observations resemble observations made for carbon, nitrogen and sulphur; i.e. a large storage, small transport, complex biogeochemical cycling processes at hand but still close to steady state conditions with respect to output-input balances. It appears as if topsoil acts as a sink for Clin, while deeper soil acts as a source of Clin. In addition, the results of the thesis suggest that on-site variation depend on seasonal variations. These variations are to some extent caused by water discharge, but also by water residence time, internal chlorination/dechlorination of organic matter, and different soil water origins. Furthermore, both a net retention and a net release of Clin were observed in laboratory studies. The study indicates that simultaneous retention and release of Clin takes place in soil, which probably has an impact on the Clin import and export fluxes. Finally, the results show for the first time that tetrachloromethane can be emitted from laboratory incubated soil, and that soil nitrogen concentrations has quite different effects on the emission rates of chloroform and tetrachloromethane. The results of the thesis, considered together with results of previous research, suggest that the turnover of chlorine in soils is extensive and potentially important for chlorine cycling in general, which must be taken into account if one wishes to increase the understanding of the cycling of anthropogenic chlorine compounds in the environment. / <p>On the day of the public defence the status of article IV was: Accepted.</p>
30

Local Cooperation in Water Management : A Minor Field Study from South India

Ståhlberg, Camilla January 2006 (has links)
<p>Decentralized development approaches have in recent years gained wide acceptance in policy circles. In India the national and the state</p><p>governments have for a long time undertaken the primary responsibility for water management. In recent years however, there has been a clear shift of policy towards increased reliance on the local communities. This thesis deals with the capacity of rural communities in India to manage their water resources in a sustainable way.</p><p>Through a case study of water management in a South Indian village opportunities and barriers for rural communities in India to manage their water resources in a sustainable way is analysed. The thesis deals with both formal and informal institutions involved in the water management.Factors that can promote and obstruct locals’ contribution in water management are discussed. Also the role of external actors such as NGOs, the Panchayats and the government is dealt with, and how they may facilitate a development towards sustainability and increased locals’ contribution in order to achieve a sustainable community bases water management.</p><p>Theories on collective action and the commons have been used in the analysis. These theories deal with how to get people to cooperate regarding the management of common resources such as water in order to achieve higher collective benefits. The study is primarily based on 66 semistructured qualitative interviews with local water users in a village in Andhra Pradesh.</p> / <p>Decentralized development approaches have in recent years gained wide acceptance in policy circles. In India the national and the state</p><p>governments have for a long time undertaken the primary responsibility for water management. In recent years however, there has been a clear shift of policy towards increased reliance on the local communities. This thesis deals with the capacity of rural communities in India to manage their water resources in a sustainable way.</p><p>Through a case study of water management in a South Indian village opportunities and barriers for rural communities in India to manage their water resources in a sustainable way is analysed. The thesis deals with both formal and informal institutions involved in the water management.Factors that can promote and obstruct locals’ contribution in water management are discussed. Also the role of external actors such as NGOs, the Panchayats and the government is dealt with, and how they may facilitate a development towards sustainability and increased locals’ contribution in order to achieve a sustainable community bases water management.</p><p>Theories on collective action and the commons have been used in the analysis. These theories deal with how to get people to cooperate regarding the management of common resources such as water in order to achieve higher collective benefits. The study is primarily based on 66 semistructured qualitative interviews with local water users in a village in Andhra Pradesh.</p> / The ISRN in the pdf-file is incorrect. The correct ISRN is shown below.

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