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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.
161

Impacts of Future Climate Change in Water Resources Management at the Chao Phraya River Basin, Thailand / タイ国チャオプラヤ川流域の水資源管理に及ぼす気候変動の影響

Luksanaree, Maneechot 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22760号 / 工博第4759号 / 新制||工||1744(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 清水 芳久, 教授 田中 宏明, 教授 米田 稔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
162

Legal framework of the water sector in Vietnam: achievements and challenges: Policy paper

Nguyen, Thi Phuong Loan 09 November 2012 (has links)
Since 1986 and especially during the early 90s, environmental protection has become a constitutional principle in Vietnam as regulated by Articles 17 and 29 of the 1992 Constitution. The first Law on Environmental Protection, passed by the National Assembly on December 27, 1993 created a foundation for environmental legislation becoming an important field in Vietnam’s legal system. In the following, Vietnam enacted its very first Law on Water Resources (No. 08/1998/QH10) in January 1999 aiming to provide a foundational framework for managing the water sector in Vietnam. In recent years, the legislative framework on water resources management has further developed. Important water-related regulations on the guidance and implementation of the Law on Water Resources have been issued and often amended to meet the requirements of the country’s development, and its international integration. To date, Vietnam’s legislation on the water sector consists of a complex system of legal documents issued by different state agencies. Though legislation of water sector management in Vietnam has greatly improved during the last decade, it has obviously not yet come to full fruition. Hence, the paper intends to provide an overview of achievements as well as problems and conflicting issues within Vietnam’s current water sector management legislation. / Kể từ năm 1986, đặc biệt là những năm đầu của thập kỷ 90, bảo vệ môi trường đã trở thành nguyên tắc hiến định (được quy định tại Điều 17 và 29 Hiến pháp 1992). Luật Bảo vệ môi trường đầu tiên được Quốc hội thông qua ngày 27 tháng 12 năm 1993 đã đặt nền móng cho việc hình thành hệ thống pháp luật về môi trường ở Việt Nam. Tiếp theo đó, ngày 20 tháng 05 năm 1998, Quốc hội nước Cộng hòa xã hội Việt Nam khóa X, kỳ họp thứ 3 đã thông qua văn bản luật đầu tiên về tài nguyên nước - Luật Tài nguyên nước số 08/1998/QH10 hình thành một nền tảng pháp lý cho hệ thống pháp luật bảo vệ nguồn tài nguyên nước ở Việt Nam. Trong những năm gần đây, hầu hết các văn bản dưới luật quan trọng và cần thiết cho việc hướng dẫn thi hành Luật Tài nguyên nước đã được ban hành và không ngừng được sửa đổi, bổ sung nhằm đáp ứng nhu cầu phát triển và hội nhập quốc tế của đất nước trong nhiều lĩnh vực khác nhau. Tuy nhiên, khung pháp lý hiện hành về tài nguyên nước ở Việt Nam bao gồm một hệ thống các văn bản quy phạm pháp luật khá phức tạp, nhiều tầng nấc, được ban hành bởi nhiều cơ quan có thẩm quyền khác nhau. Mặc dù hệ thống pháp luật về tài nguyên nước đã được liên tục sửa đổi, bổ sung và hoàn thiện trong suốt một thập kỷ qua, nhưng rõ ràng vẫn chưa thực sự đi vào cuộc sống. Bài viết dưới đây đề cập chủ yến đến một số các thành tựu cũng như những vấn đề mâu thuẫn hiện tại của pháp luật bảo vệ nguồn tài nguyên nước ở Việt Nam.
163

An Integrated Land Use and Water Plan for Mahasarakham Province, Thailand

Ongkosit, Yuwadee January 2013 (has links)
No description available.
164

MONITORING STORMWATER INFILTRATION IN A VACANT LOT COMPARING TIME-LAPSE ELECTROMAGNETIC INDUCTION AND ELECTRICAL RESISTIVITY TOMOGRAPHY

Carsillo, Vincent John January 2018 (has links)
Vacant lots in cities and surrounding urban areas can potentially be used for stormwater management because they are pervious. However, the extent to which vacant lots provide pervious cover to increase infiltration and reduce stormflow is poorly understood. The goal of this study was to develop faster methods for monitoring stormwater infiltration to improve characterization of heterogeneous urban systems. Geophysical techniques are capable of mapping and characterizing subsurface materials, but are often limited by time and sensitivity constraints. In this study, the infiltration characteristics of a vacant lot created by the demolition of a house was characterized using a series of modeling, field and lab experiments. Site characterization under background conditions with an EM Profiler was used to map zones of different fill materials. Three zones were identified in the study site: grass area, driveway area, and a former house area. Transient soil moisture conditions were monitored during irrigation tests using two geophysical methods (electrical resistivity tomography [ERT] and electromagnetic induction [EM]) to evaluate method sensitivity and differences between the three zones. ERT proved more sensitive than EM profiling at detecting changes in the three zones. Soil moisture changes in the driveway area were particularly difficult to detect using EM. The EM Profiler showed a reduction rather than increase in conductivity at the start of irrigation and storms, which was attributed to flushing of high conductivity pore fluids by dilute irrigation or rain water. This explanation was supported using Archie’s Law to model the response of apparent conductivity under highly conductive pore fluid conditions. The EM Profiler was also used under natural precipitation conditions to quickly monitor areas too large for the ERT to reasonably survey. The results suggested that EM instrument drift needs to be corrected to make the method more sensitive. It was difficult to detect differences in hydrologic characterization between areas of the vacant lot using traditional soil point measurements because of the inherent spatial variability. The most useful point measurement was soil moisture loggers. Data from soil moisture loggers was used to parameterize the model; in addition, the soil moisture loggers showed a slow drying period. By combining the EM Profiler method with soil moisture data and applying corrections for drift, some improvement in sensitivity might be achieved. Quantitative characterization of fill material was shown by ERT, which detected more heterogeneous infiltration in the area of the former house than in the grass area. / Geology
165

COMBINED OZONE AND ULTRASOUND PROCESS FOR THE DESTRUCTION OF 1,4-DIOXANE IN CONTINUOUS FLOW REACTOR

Dietrich, Michael Thomas January 2016 (has links)
Clean water is essential to life. Growth in world population, changing diets, and a warming climate are driving an increase in the demand for water. Better management of water resources will help prevent scarcity, but in order to fully meet the future demand for safe, clean drinking water, new water treatment technologies are needed. This dissertation investigates a technology which is not well understood; the combination of ozone and ultrasound as potentially an efficient technology. Since nearly all previously published studies of combined ozone/ultrasound utilized batch reactors, a continuous flow reactor was constructed for this research. 1,4-Dioxane, henceforth referred to as dioxane, was chosen to evaluate the effectiveness of the combined ozone/ultrasound process. Dioxane is commonly detected in surface and groundwater and is a suspected human carcinogen. A recalcitrant contaminant, it resists direct oxidation by chlorine, oxygen, ozone, and biological treatment. It is miscible in water and doesn't sorb readily to organic matter, so it spreads rapidly in groundwater contamination plumes. It also resists air stripping and filtration, including reverse osmosis. For these reasons, dioxane makes an excellent candidate to measure the effectiveness of advanced oxidation processes, such as combined ozone/ultrasound. The treatment of dioxane by advanced oxidation processes has been studied extensively in the past. However, only one study has been published using combined ozone/ultrasound, and it was done in a batch reactor operating at a high ultrasonic frequency. The reactor built for this study also permitted reactor pressurization effects to be studied in a manner that has not been reported before for the combined ozone/ultrasound process. In this study, the combination of ozone and ultrasound was found to cause synergistic removal of dioxane from drinking water; the removal achieved by the combination significantly exceeded the sum of the removal achieved by ozone and ultrasound separately. In fact, the combination of ozone and ultrasound was found to remove more than double the dioxane that would be removed by doing both treatment processes separately. Ultrasound (20 kHz) was ineffective in removing dioxane alone, achieving less than 20% removal. At 16 mg/L, ozone alone was found to achieve removal of up to 86% after a 16 minute treatment time, but appears sensitive to matrix effects, especially pH. When ultrasound was combined with just 1.2 mg/L of aqueous ozone, over 90% removal occurred after a 16 minute treatment. Removal of dioxane was found to be driven not by ozone itself, but by radicals, suggesting that the decomposition of ozone is responsible for the generation of radical species and subsequent removal of dioxane. Ultrasound was found to increase the decomposition of ozone and appeared to be driving increased mass transfer of ozone into the aqueous phase. Modest reactor pressure appears to aid dioxane removal, but further increases in pressure did not appear to further enhance removal. An empirical model was constructed using a form similar to the Chick & Watson model for disinfection. Given inputs of initial aqueous ozone concentration, initial dioxane concentration, treatment time, and ultrasonic power, the model is able to predict effluent concentrations of dioxane with a relative root mean squared error of less than 5%. Additionally, RCT and mass balance analyses were performed, and both analysis techniques suggested that the removal of dioxane is dependent on the consumption of aqueous ozone. Spiked drinking water is representative of water that has undergone conventional treatment but requires a polishing step, and the combined ozone/ultrasound has shown promise as a polishing technology. Owing to its recalcitrance, prevalence, and mobility, dioxane represents a real and challenging groundwater contaminant, and combined ozone/ultrasound has shown promise as a groundwater treatment option. Additionally, the process is capable of dioxane removal in a pH range of 4-10. This pH independence, coupled with its ability to degrade recalcitrant contaminants, suggests that combined ozone/ultrasound holds promise as an industrial wastewater treatment option, too. The removal achieved by both ozone and combined ozone/ultrasound was an order of magnitude greater than what has been reported in previously published reports. However, a comparison of cost effectiveness relative to other advanced oxidation processes remains an area for future study. Finally, the combined ozone/ultrasound process holds promise as a drinking water treatment option in remote areas, since it requires only electricity. As a promising technology for polishing water for reuse, treating contaminated groundwater, treating industrial wastewater, and potentially improving access to safe drinking water in remote areas, combined ozone/ultrasound could aid in meeting global water demand in the future. / Civil Engineering
166

CO-PRODUCTION OF GEOGRAPHIC KNOWLEDGE FOR THE SOCIO-ECOLOGICAL RESTORATION AND DEMOCRATIC GOVERNANCE OF URBAN-RURAL RIPARIAN ZONES IN MEDELLIN, COLOMBIA.

Saenz Montoya, Alexis January 2020 (has links)
Progressive scholars have found in community-engaged research and participatory methodologies a synergistic approach for pursuing transformative co-production of knowledge to understand the complexity of critical social and environmental issues. According to Jasanooff (2004), the co-production of knowledge is "the simultaneous process through which modern societies form their epistemic and normative understandings of the world." This dissertation project has sought the co-production of geographic knowledge in socio-environmental research on stream restoration, co-produced between academics and community activists in Medellin, Colombia. Specifically, the intent of the research has been to examine the latent power of affect and feeling to promote the ecological care of streams and their surrounding basins, and to understand the possibilities of mapping the desires that local ecological actors have for stream restoration. Papers one and two also made key contributions to understanding how environmental and social actors surrounding La Honda stream are or could contribute to a scenario of the stream basin’s ecological care. In paper three I detailed my work on the ElAtlas initiative. There I documented the rich historical process we went through to build ElAtlas. I described how the initiative involved the convergence of different participatory approaches in GIS, such as Public Participatory GIS (PPGIS), and Volunteered Geographic Information (VGI), and richly detailed the three different stages of the initiative. / Geography
167

Ecohydrologic Indicators of Low-flow Habitat Availability in Eleven Virginia Rivers

Hoffman, Kinsey H. 26 October 2015 (has links)
Increasing demand and competition for freshwater is threatening instream uses including ecosystem services and aquatic habitat. A standard method of evaluating impacts of alternative water management scenarios on instream habitat is Instream Flow Incremental Methodology (IFIM). The primary outputs of IFIM studies are: 1) habitat rating curves that relate habitat availability to streamflow for every species, lifestage, or recreational use modelled; and 2) habitat time series under alternative water management scenarios. We compiled 428 habitat rating curves from previous IFIM studies across 11 rivers in Virginia and tested the ability to reduce this number based on similarities in flow preferences and responses to flow alteration. Individual site-species combinations were reduced from 428 objects to four groups with similar seasonal habitat availability patterns using a hierarchical, agglomerative cluster analysis. A seasonal habitat availability (SHA) ratio was proposed as a future indicator of seasonal flow preferences. Four parameters calculated from the magnitude and shape of habitat rating curves were proposed as response metrics that indicate how a lifestage responds to flow alteration. Univariate and multivariate analyses of variance and post-hoc tests identified significantly different means for the SHA ratio, QP (F=63.2, p<2e-16) and SK (F=65.6, p<2e-16). A reduced number of instream flow users can simplify the incorporation of aquatic habitat assessment in statewide water resources management. / Master of Science
168

Application of integrated water resources management in computer simulation of River Basin's status - case study of River Rwizi

Atim, Janet 06 1900 (has links)
Thesis (M. Tech. - (Civil Engineering, Faculty of Engineering and Technology))--Vaal University of Technology, 2010. / During the last few years, concern has been growing among many stakeholders all over the world about declining levels of surface water bodies accompanied by reduced water availability predominantly due to ever increasing demand and misuse. Furthermore, overexploitation of environmental resources and haphazard dumping of waste has made the little water remaining to be so contaminated that a dedicated rehabilitation/remediation of the environment is the only proactive way forward. River Rwizi Catchment is an environment in the focus of this statement. The overall objective of this research was to plan, restore and rationally allocate the water resources in any river basin with similar attributes to the study area. In this research, Integrated Water Resources Management (IWRM) methodology was applied through Watershed/Basin Simulation Models for general river basins. The model chosen and used after subjection to several criteria was DHI Model, MIKE BASIN 2009 Version. It was then appropriately developed through calibration on data from the study catchment, input data formatting and its adaptation to the catchment characteristics. The methodology involved using spatio-temporal demographic and hydrometeorological data. It was established that the model can be used to predict the impact of projects on the already existing enviro-hydrological system while assigning priority to water users and usage as would be deemed necessary, which is a significant procedure in IWRM-based environmental rehabilitation/remediation. The setback was that the available records from the various offices visited had a lot of data gaps that would affect the degree of accuracy of the output. These gaps were appropriately infilled and gave an overall output that was adequate for inferences made therefrom. Several scenarios tested included; use and abstraction for the present river situation, the effect of wet/dry seasons on the resultant water available for use, and proposed projects being constructed on and along the river. Results indicated that the river had insufficient flow to sustain both the current and proposed water users. It was concluded that irrespective of over exploitation, lack of adequate rainfall was not a reason for the low discharge but rather the loss of rainwater as evaporation, storage in swamps/wetlands, and a considerable amount of water recharging groundwater aquifers. Thus, the proposed remedy is to increase the exploitation of the groundwater resource in the area and reduce the number of direct river water users, improve farming methods and conjunctive use of groundwater and surface water - the latter as a dam on River Rwizi. The advantage of the dam is that the water usage can be controlled as necessary in contrast to unregulated direct abstraction, thus reducing the risk of subsequent over-exploitation. / Vaal University of Technology
169

Ökonomische und ökologische Bewertung der Auswirkungen des demografischen Wandels auf die Siedlungsentwässerung

Bergheim, Kirtan, Dreuse, Alexander, Reif, Jakob 17 April 2013 (has links) (PDF)
Der demografische Wandel in Sachsen stellt Unternehmen der Siedlungsentwässerung vor neue Herausforderungen und innovative Lösungsansätze. Eine Abnahme der Siedlungsdichte infolge rückgängiger Bevölkerungszahlen bringt neue Anforderungen an das Ver- und Entsorgungsnetz für Wasser mit sich. In den nächsten Jahren werden sich im Bereich der Siedlungsentwässerung des Freistaates aufgrund der Wasserrahmenrichtlinie, nach der bis 2015 alle sächsischen Grundstücke an eine Abwasserentsorgungsanlage angeschlossen werden müssen, weitreichende Veränderungen ereignen. Die Lebensdauer verschiedener Bestandteile des Abwassersystems variiert zwischen wenigen Jahren und mehreren Jahrzehnten. Neben hohen Investitionskosten fallen daher bei einem Teil der Anlagen auch signifikante Kosten für Betrieb, Wartung, Sanierung und Deinstallation an. Daher ist es sinnvoll in der Projektplanung einer solchen Anlage nicht nur die Kosten der reinen Anschaffung zu betrachten, sondern die Kosten des gesamten Lebenszyklus in die Berechnung zu integrieren. In dieser Arbeit soll die Methodik der Lebenszykluskostenrechnung in der Siedlungsentwässerung angewendet werden. Im Rahmen des vom Bundesministerium für Bildung und Forschung, dem Freistaat Sachsen und der Emschergenossenschaft finanzierten Projektes Auswirkungen des demografischen Wandels auf die Siedlungsentwässerung sind weitere Veröffentlichungen mit den Schwerpunktthemen Szenarioanalyse (Teil 1) und Ökologische Bewertung (Teil 3) in der Schriftenreihe „Dresdner Beiträge zur Lehre der Betrieblichen Umweltökonomie“ erhältlich.
170

Political culture and socialisation responses to integrated water resources management (IWRM) : the case of Thabo Mofutsanyane District Municipality / Sysman Motloung

Motloung, Sysman January 2010 (has links)
This study looks at political culture and socialisation responses to Integrated Water Resource Management (IWRM). It identifies political culture and socialisation as part of a process, the development of a political culture with specific attitudes, cognitions, and feelings towards the political system. Political culture and socialisation impart the knowledge of how to act politically, i.e. how to apply values in formulating demands and making claims on the political system. They form a connecting link between micro- and macro-politics. The study maintains that political orientations are handed down from one generation to another, through the process of political socialisation. Top-down and bottom-up influences come into play to augment a discourse on the global nature of political socialisation and the political culture of international societies with regard to IWRM and governance ideologies. It is argued that these international ideas become relevant in the national political agenda, civil society organisations and trans-national networks. The IWRM aspects of water as an economic good and a basic human right have become a two-edged sword in the South African context. The study reveals that politics stand at the epicentre of water problems, and that IWRM is a political-ethical issue which challenges power bases in many communities. The IWRM global norms of equitable, efficient and sustainable use of water resources have become a major problem in a water-scarce country burdened with economic inequalities and abject poverty. This is a pressing issue because there is an increasing demand for water to sustain the development necessary to redress the draconian ills of the apartheid past. This becomes evident in the fundamental legislative overhaul that has taken place since 1994, embracing a transformation culture that glorifies the norm of water not only as a fundamental human right, but also as a commodity that is necessary to sustain human dignity. It is here that water is politicised. Violent protests have erupted in reaction to perceived neo-liberal attempts to deny the poor their access to this resource. The political culture and socialisation responses as far as IWRM is concerned appear within fragmented lines, i.e. mainly black and poor communities embrace a culture of non-payment for services and resort to violent protests as a viable method to raise their concerns. In contrast, the white and middle-class communities manifest a tendency to form parallel local government structures; they then withhold rate payments and provide services for themselves through ratepayer associations. Finally, the study considers the South African context with regard to the manifestations of political culture, and how this influences water resources. It is evident that there is too much emphasis on politics at the expense of discussions on IWRM. Civil society organisations make very little attempt to encourage public participation in water management structures. It also appears that political elites who are disillusioned with civil society organisations tend to derail their efforts to educate the public on water management structures. / MA, Political Studies, North-West University, Vaal Triangle Campus, 2011

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