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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.
51

Modelling the Effects of Deforestation on Stream Flows in Arror River Basin-Kenya

Muli, Cosmus January 2007 (has links)
<p>Abstract.</p><p>Like other developing countries, forest conversion to agricultural land has been a common practice in Kenya for the last four decades. Apart from illegal logging, the main cause is the growing population. For most developing countries where majority rely on agriculture for food production, conversion of forests into agricultural land is likely to occur. Kenya is one among such countries and is where the study basin is located. Knowledge of hydrological studies is crucial for proper planning and decision making of limited water resources in river basins. Even in regions where data is limited, changes in land use is a concern to many basin communities over the globe including Arror inhabitants since it has an impact on stream flows. Despite Arror downstream communities’ claims on reducing river flows, scientific proof on this is lacking. Such kind of belief/claim can result to conflicts (Downstream vs. Upstream water users). The main objective of this thesis was therefore to determine the effect of land use changes on Arror basin hydrology, focusing on the impact of deforestation since it has been the main land use change for the last four decades. The overall intention of the study is to verify the downstream basin’s inhabitant’s hypothetical thinking and also create an information foundation base for other future studies in the basin. Based on the lessons learned in this study, several recommendations have been highlighted, including land satellite rainfall data to augment the rainfall data obtained from the relatively sparse rain gauge network in the basin.</p>
52

Decentralised Management and Community Participation : A Minor Field Study about Irrigation and Communication in Central India

Glaas, Erik January 2007 (has links)
<p>India and many other developing countries confront serious problems of declining water tables. In India there is no real water shortage, but ineffective use of surface water leads to freshwater run-off. By building dams and irrigation water systems the Indian government has been trying to find a more effective use of surface water and thereby increase the agricultural productivity. But mismanagement of irrigation systems by local governments called for alternative management techniques, and during the last decades the central Indian government has been trying to decentralise management and governance of irrigation water to local water users. This Minor Field Study (MFS) focuses on a local implementation of Participatory Irrigation Management in the Indian state Madhya Pradesh. The aim of the thesis is to analyse the way the local government handles the decentralisation of irrigation water management, by identify and illuminate communication channels. The thesis is built on the basic idea that functioning environmental communication is the key to reach a functioning decentralised and sustainable water management. Interviews with local government officials, citizens of a local village, and staff from a locally involved NGO within a case study constitute most of the empirical data. Theories of decentralisation of natural resource management, community participation, communication, and NGO cooperation are presented. With starting point in the empirical material and the presented theories has way the local government handles the decentralisation process, and the role of the locally involved NGO, been analysed. The study shows shortcomings in: education of stakeholders, communication training among government officials, trust in the capability of local water users, and communication between stakeholders. The study also enlighten the government officials fear of losing political power, the NGOs role as communication channel, and the formation of locally rooted organisations.</p>
53

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>
54

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>
55

Changing States: Using State-and-Transition Models to Evaluate Channel Evolution Following Dam Removal Along the Clark Fork River, Montana

Van Dyke, Christopher 01 January 2015 (has links)
Located just east of Missoula, Montana, Milltown Dam stood from 1908 to 2008 immediately downstream of the Clark Fork River’s confluence with the Blackfoot River. After the discovery of arsenic-contaminated groundwater in the nearby community of Milltown, as well as extensive deposits of contaminated sediment in the dam’s upstream reservoir, in 1981, the area was designated a Superfund site – along with much of the Upper Clark Fork Watershed. This motivated the eventual decision to remove the dam, perform environmental remediation, and reconstruct approximately five kilometers of the Clark Fork River and its floodplain. This study is part conceptual and part empirical. It describes a state-and-transition framework equipped to investigate channel evolution as well as the adjustment trajectories of other socio-biophysical landscapes. This framework is then applied to understand the post-restoration channel evolution of the Clark Fork River’s mainstem, secondary channels, and floodplain. Adopting a state-and-transition framework to conceptualize landscape evolution lets environmental managers more effectively anticipate river response under multiple disturbence scenarios and therefore use more improvisational and adaptive management techniques that do not attempt to guide the landscape toward a single and permanent end state. State-and-transition models can also be used to highlight the spatially explicit patterns of complex biophysical response. The state-and-transition models developed for the Clark Fork River demonstrate the possibility of multiple evolutionary trajectories. Neither the secondary channels nor the main channel have responded in a linear, monotonic fashion, and future responses will be contingent upon hydrogeomorphic and climatic variability and chance disturbances. The biogeomorphic adjustments observed so far suggest divergent evolutionary trajectories and that in some instances the long-term fates of the mainstem, floodplain, and secondary channels are inescapably enmeshed with one another.
56

Dine Food Sovereignty: Decolonization through the Lens of Food

Tso, Mariah 01 January 2014 (has links)
Food deserts are low-income areas lacking access to nutritious and affordable food. Such limited access has various implications for public health, particularly diet-related diseases such as diabetes. Among American Indian communities, diabetes is particularly rampant at nearly twice the rate of white populations in the U.S. On the Navajo Nation, diabetes incidence has been estimated to be as high as 1 in 3. According to the USDA, the majority of the Navajo Nation is considered a food desert. This paper utilizes food sovereignty as a lens for decolonization to identify the underlying causes of hunger and nutrition-related diseases within Diné communities. This paper will explore the histories of the change in the Diné diet and how colonial processes and the loss of traditional food systems affects current food and health patterns on the Navajo Nation. By expanding the scope of public health issues such as obesity and diabetes in Native American communities from food access and nutrition to power relations embedded in colonial structures that have resulted in the loss of indigenous sovereignty and power, I hope to pinpoint entry points for future indigenous researchers to develop and enact policies that will expand access to healthy and culturally significant foods on the Navajo Nation and contribute to efforts to restore food sovereignty of the Navajo Nation by rebuilding local food economies.
57

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.
58

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>
59

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.
60

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.

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