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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.
291

A Discussion of the Impact of Political and Economic Forces on Equitable Access to Potable Water in Ecuador and Recommendations for Improvement through Better Watershed Management

States, Eliza 01 January 2014 (has links)
This thesis will address the impact of political and economic forces on the equitable access to fresh water in Ecuador. Demographic factors such as the rural-to-urban migration and the political and economic forces have strongly influenced the debate over the privatization of the provision of potable water and sanitation services. Within the context of Ecuador, two different approaches by the largest cities, Quito and Guayaquil, are analyzed; in Guayaquil, the services were privatized, while in Quito, the public utility was corporatized, remaining under public control. It concludes arguing that in the face of political instability and a lack of regulatory enforcement, neither public nor private provision adequately supplies marginalized communities with water and sanitation services. Watershed management is therefore crucial to maintaining a sound city water-management plan. Its flexibility and openness to innovative alliances between various stakeholders creates great potential for this approach.
292

Real time optimal water allocation in the Orange River catchment in South Africa

Olofintoye, Oluwatosin Onaopemipo January 2015 (has links)
Submitted in fulfillment of the requirements of the degree of Doctor of Engineering: Civil Engineering, Durban University of Technology. Durban. South Africa, 2015. / The planning and management of water resources systems often involve formulation and establishment of optimal operating policies and the study of trade-off between different objectives. Due to the intricate nature of water resources management tasks, several models with varying degrees of complexities have been developed and applied for resolving water resources optimisation and allocation problems. Nevertheless, there still exist uncertainties about finding a generally consistent and trustworthy method that can find solutions which are very close to the global optimum in all scenarios. This study presents the development and application of a new evolutionary multi-objective optimisation algorithm, combined Pareto multi-objective differential evolution (CPMDE). The algorithm combines methods of Pareto ranking and Pareto dominance selections to implement a novel generational selection scheme. The new scheme provides a systematic approach for controlling elitism of the population which results in the simultaneous creation of short solution vectors that are suitable for local search and long vectors suitable for global search. By incorporating combined Pareto procedures, CPMDE is able to adaptively balance exploitation of non-dominated solutions found with exploration of the search space. Thus, it is able to escape all local optima and converge to the global Pareto-optimal front. The performance of CPMDE was compared with 14 state-of-the-art evolutionary multi-objective optimisation algorithms. A total of ten test problems and three real world problems were considered in the benchmark of the algorithm. Findings suggest that the new algorithm presents an improvement in convergence to global Pareto-optimal fronts especially on deceptive multi-modal functions where CPMDE clearly outperformed all other algorithms in convergence and diversity. The convergence metric on this problem was several orders of magnitude better than those of the other algorithms. Competitive results obtained from the benchmark of CPMDE suggest that it is a good alternative for solving real multi-objective optimisation problems. Also, values of a variance statistics further indicate that CPMDE is reliable and stable in finding solutions and converging to Pareto-optimal fronts in multi-objective optimisation problems. CPMDE was applied to resolve water allocation problems in the Orange River catchment in South Africa. Results obtained from the applications of CPMDE suggest it represents an improvement over some existing methods. CPMDE was applied to resolve water allocation problems in the agricultural and power sectors in South Africa. These sectors are strategic in forging economic growth, sustaining technological developments and contributing further to the overall development of the nation. They are also germane in capacitating the South African government’s commitment towards equity and poverty eradication and ensuring food security. Harnessing more hydropower from existing water sources within the frontier of the country is germane in capacitating the South African Government’s commitment to reduction of the countries’ greenhouse gas emissions and transition to a low-carbon economy while meeting a national target of 3 725 megawatts by 2030. Application of CPMDE algorithm in the behavioural analysis of the Vanderkloof reservoir showed an increase of 20 310 MWH in energy generation corresponding to a 3.2 percent increase. On analysis of storage trajectories over the operating period, it was found that the real time analysis incorporating a hybrid between CPMDE and ANN offers a procedure with a high ability to minimize deviation from target storage under the prevailing water stress condition. Overall, the real time analysis provides an improvement of 49.32 percent over the current practice. Further analysis involving starting the simulation with a proposed higher storage volume suggests that 728.53 GWH of annual energy may be generated from the reservoir under medium flow condition without system failure as opposed to 629 GWH produced from current practice. This corresponds to a 13.66 percent increase in energy generation. It was however noted that the water resources of the dam is not in excess. The water in the dam is just enough to meet all current demands. This calls for proper management policies for future operation of the reservoir to guard against excessive storage depletions. The study herein also involved the development of a decision support system for the daily operation of the Vanderkloof reservoir. This provides a low cost solution methodology suitable for the sustainable operation of the Vanderkloof dam in South Africa. Adopting real time optimisation strategies may be beneficial to the operation of reservoirs. Findings from the study herein indicate that the new algorithm represents an improvement over existing methods. Therefore, CPMDE presents a new tool that nations can adapt for the proper management of water resources towards the overall prosperity of their populace. / D
293

Perspectives on Policy Framework for Trans-Boundary Water Quality Management in China

Zhang, Wei, Zhen, Gengchong, Tong, Yindong, Yang, Lei, Zhu, Yan, Liu, Guohua, Wang, Xuejun, Li, Ying 02 April 2016 (has links)
In river basins that cross jurisdictional boundaries, water quality degradation has become a crucial problem and results in intensive competition among water users, especially in developing countries. Under this situation, implementing water quality management and control across jurisdictional boundaries can strengthen watershed pollution controls, and prevent pollution from being passed on and promote active pollution control within the related jurisdictional regions. This study examined the limitations of the current trans-boundary water quality management system in China and reviewed the planning and implementation of two pilot integrated trans-boundary water management systems established in the Jiangsu and Zhejiang provinces. Based on our findings, we proposed a new policy framework for trans-boundary water quality management. As a first step toward integrated watershed management in China, this policy framework can help assess the actual water pollution status of various regions and serve as a basis for an integrated watershed management system. The framework can be easily applied in other countries with trans-boundary water pollution issues, particularly in the context of developing countries.
294

Participatory watershed management to decrease land degradation and sediment transport in Kagera and Nyando catchments of Lake Victoria basin

Kenge, James Gunya January 2009 (has links)
<p>Attention to participatory watershed management is increasing across the developing world<em> </em>as<em> </em>soil erosion continues to degrade agricultural land; reservoirs and irrigation infrastructure are clogged with sediment. The realization of the importance of watersheds is crucial for sustainable utilization especially in developing countries where rural livelihoods and economies are highly dependant on the exploitation of natural resources. The Lake Victoria basin is characterized by high population pressures, low productive subsistence agriculture, poor farming methods, loss of soil fertility and deforestation due to demand of fuel wood and charcoal, timber and building materials that are posing serious threat to watersheds. High population density in the basin also means new needs emerge too fast to which rural societies cannot respond in time leading to more area expansion for agricultural land. In spite of positive efforts under the Lake Victoria Basin Commission, there remains a huge gap between policy and institutional framework development at the top level and the actual implementation of actions on the ground to prevent land degradation, soil erosion and decrease sediment load. The study focused on Kagera and Nyando catchments of Lake Victoria Basin and aiming to establish if there exist and the extent to which participatory watershed management has been implemented on the ground to decrease land degradation and sediment load. It therefore provides an insight into watershed management in the Kagera and Nyando catchments by illustrating the link between policy formulation and actual implementation and enforcement.</p>
295

Participatory watershed management to decrease land degradation and sediment transport in Kagera and Nyando catchments of Lake Victoria basin

Kenge, James Gunya January 2009 (has links)
Attention to participatory watershed management is increasing across the developing world as soil erosion continues to degrade agricultural land; reservoirs and irrigation infrastructure are clogged with sediment. The realization of the importance of watersheds is crucial for sustainable utilization especially in developing countries where rural livelihoods and economies are highly dependant on the exploitation of natural resources. The Lake Victoria basin is characterized by high population pressures, low productive subsistence agriculture, poor farming methods, loss of soil fertility and deforestation due to demand of fuel wood and charcoal, timber and building materials that are posing serious threat to watersheds. High population density in the basin also means new needs emerge too fast to which rural societies cannot respond in time leading to more area expansion for agricultural land. In spite of positive efforts under the Lake Victoria Basin Commission, there remains a huge gap between policy and institutional framework development at the top level and the actual implementation of actions on the ground to prevent land degradation, soil erosion and decrease sediment load. The study focused on Kagera and Nyando catchments of Lake Victoria Basin and aiming to establish if there exist and the extent to which participatory watershed management has been implemented on the ground to decrease land degradation and sediment load. It therefore provides an insight into watershed management in the Kagera and Nyando catchments by illustrating the link between policy formulation and actual implementation and enforcement.
296

Application of Integrated Watershed Management Modeling on Non-point Source Pollution Evaluation for the Ai-Liao River Basin

Shen, Wei-Lin 23 August 2006 (has links)
In Taiwan, non-point source (NPS) pollution is one of the major causes of the impairment of surface waters. NPS pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. The I-Liao Creek Basin, located in southern Taiwan, flows through approximately 90-km and drains towards the Kaoping River. It is one of the major sub-basin in the Kaoping River watershed, which is the largest and the most intensively used watershed in Taiwan. Field investigation results indicate that the main water pollution sources in the I-Liao Creek Basin are domestic wastewater and NPS pollutants from agricultural activities. In this study, an Integrated Watershed Management Model (IWMM) was applied for simulating the water quality in the I-Liao Creek watershed. The model includes a global atmosphere module, a land module, a human impact module, a canopy module, and a global ocean module. Those modules can be linked and managed by a graphic user-interface. The model was calibrated and verified with field data, and was used to investigate potential NPS pollution management plans. Moreover, the Storm Water Management Model (SWMM) was used to verify the accuracy of the simulated results of flow and water qualities. Results from this study show that geographical information system (GIS) is an important mean for land-use identification and waste load estimation in the catchment. Linking the information of land utilization with the NPS pollution simulation model may further provide essential information of pollution potential of NPS pollution for all sub-regions in the river basin. Results and experience obtained from this study will be helpful in designing the watershed management and NPS pollution control strategies for other similar river basins.
297

Impact of mine land reforestation and revegetation on water quality in a mid-Appalachian watershed a stream monitoring study /

Wei, Honghong, January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains viii, 92 p. : ill., maps (some col.). Includes abstract. Includes bibliographical references (p. 56-62).
298

A GIS expert system for the delineation of watersheds in low-relief regions with rural infrastructure

Duke, Guy D., University of Lethbridge. Faculty of Arts and Science January 2003 (has links)
Grid-based digital elevation models (DEMs) are used to simulate overland flow paths in hydrological models. The accuracy of these drainage patterns are dependent upon how well the DEM represents the terrain features that control runoff patterns. Often regional DEMs are not produced at scales small enough to represent rural infrastructure. The scale of runoff patterns that can be accurately modeled is, therefore, restricted, particularly when the terrain is relatively flat. The RIDEM (Rural Infrastructure Digital Elevation Model) model is presented that utilizes commonly available ancillary data to downscale grid-based runoff patterns. The resulting drainage patterns reflect drainage modifications imposed by rural infrastructure including: roads, ditches, culverts, and irrigation canals. Downscaling runoff patterns enables the completion of runoff studies at smaller scales. The model was implemented with the Oldman River watershed, Alberta, Canada to determine the spatial patterns of potential runoff contributing areas in three agricultural watersheds regularly contaminated by pathogens. / vii, 170 leaves : ill. (some col.) ; 29 cm.
299

Watershed master planning for St. Lucia using geographic information systems

Cox, Christopher, 1967- January 1997 (has links)
A method for estimating long-term average annual soil loss under different land management scenarios from the Marquis and Soufriere watersheds on St. Lucia is presented. The Revised Universal Soil Loss Equation (RUSLE) was used, and a GIS was employed to generate the required input parameters. Model execution and results were also generated within the GIS. Modelling soil loss for the different land management scenarios was based upon a land capability classification and associated conservation treatments. Soil losses under current agricultural land-use patterns were analyzed and compared to potential soil losses under conservation treatments following the criteria specified in the land capability classification. The model predicted substantial declines in soil loss where conservation treatments were assigned, as compared to soil loss under current land-use patterns. It was found that predicted soil losses from the Soufriere watershed were four times that predicted for the Marquis watershed for all the land management scenarios modelled. Of the input parameters in the model, slope steepness was most highly correlated to predicted soil loss. It is anticipated that the findings of this study will be used in the development of a decision support system for agricultural and forestry land planning on St. Lucia.
300

Stakeholder participation in the establishment of the Berg Catchment Management Agency, South Africa.

Gueze, Humberto. January 2007 (has links)
<p>Enacted in 1998, the New South African Water Act has introduced a new approach to water resource management, founded on the principle of decentralization of the management of water resources to regional and local levels and the public participation. The approach has been captured in the new National Water Act (Act 36 of 1998), which allows the establishment of Catchment Management Agencies. The overall purpose of this study was to understand the trends of public participation in the establishment of Catchment Management Agencies in South Africa, by presenting the case of the Berg Catchment Management Agency.</p>

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