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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.
251

Riverhelp!: sistema de suporte a decisões para planejamento e gerenciamento integrado de recursos hídricos / Riverhelp!: decision suport system for integrated water resources planning and management

Lima, Guilherme de 31 August 2007 (has links)
Esta pesquisa apresenta um sistema de suporte a decisão (SSD) para o planejamento e gerenciamento integrado de bacias hidrográficas, denominado Riverhelp!, e também sugere nova metodologia para o uso desse tipo de ferramenta de análise. O objetivo geral é desenvolver um SSD que possa auxiliar a gestão de recursos hídricos. Para isso o SSD utiliza e integra tecnologias avançadas em um só sistema computacional flexível e que pode ser utilizado e entendido por especialistas e outros participantes do processo decisório. O programa é composto por quatro módulos principais e tem código aberto baseado na tecnologia OpenMI o que permite aos usuários alterar e incluir funções. Outra propriedade que merece destaque é sua completa integração com um sistema de informações geográficas permitindo a análise temporal e espacial da bacia hidrográfica. Essa ferramenta pode, por exemplo, ser usada para análises de disponibilidade de água em quantidade e qualidade, para o estudo de ecossistemas, para a otimização e operação de reservatórios e para auxiliar no processo de outorga de direito de uso da água. Uma aplicação do Riverhelp! para as bacias hidrográficas dos rios Piracicaba, Capivari e Jundiaí ilustra as diversas possibilidades de uso do sistema. Os resultados dessa investigação reforçam a importância e a necessidade de uma nova geração de SSD que considerem e analisem de maneira integrada os complexos assuntos relacionados à gestão da bacia hidrográfica. O desenvolvimento do Riverhelp! contribui significativamente para o avanço das pesquisas relacionadas ao tema de planejamento e gerenciamento integrado de recursos hídricos fornecendo um SSD com características únicas, que associa ferramentas para avaliação ambiental, modelos de simulação e otimização de qualidade e quantidade de água superficial e subterrânea, sistema de informações geográficas, diferentes bancos de dados, funções para análises estatísticas e técnicas multiobjetivo para análise de cenários. / This research presents a decision support system (DSS) for integrated water resources planning and management (IWRM) named Riverhelp! and suggests new methodology for the use of this kind of analysis tool as well. The general goal is to develop an appropriate DSS that can help IWRM process. In order to do so, the DSS uses and combines advanced technologies and techniques currently available. It integrates different methodologies in just one computational system, which is flexible and can be used and understood not only by specialists but also by general users who are not familiar with modelling. The DSS Riverhelp! has four main building blocks and an open computational core based on the OpenMI technology which allows users to access it programmatically and to add new tools or to change computations in almost any way they want. Another important characteristic is that the DSS Riverhelp! is fully integrated with a geographic information system (GIS). Most of all, it puts time and spatial information together and is therefore a great package for data management of river basins. This system can be used for hydrological analyses, assessment of water availability, water resources planning, water quality and quantity studies, reservoir systems nonlinear optimization and so on. In this research a Riverhelp! application for the Piraciaba, Capivari and Jundiaí river basins shows several possibilities for its use. The results of this study emphasize the importance and necessity of a new generation of decision support systems that are able to analyze and take into account the complex issues associated to river basin management in an integrated approach. The Riverhelp! development makes significant contributions for research advance in the integrated water resources planning and management field providing a DDS with unique characteristics that combines environmental assessment tools, water quality and quantity simulation and optimization models for surface water and groundwater, geographic information system, sophisticated databases, statistical tools and multicriteria techniques for scenario analyses.
252

Návrh malé vodní nádrže s retenčním účinkem v katastrálním území obce Police. / Retention Reservoir Design in the Police Cadastr

Hadaš, Zdeněk January 2014 (has links)
This thesis deals with the river basin flood protection Loučka. The goal of the thesis is to assess the need of flood control measures supplement in the watershed. The first part deals with exploration of river basin, acquiring geographic factors and obtaining information about the topic, establishment and application of rainfall model used for solving the problem. The second part deals with improving of flood protection at critical selected places by using design of reservoir system with retention effect and by increasing river basin capacity. For basin schematisation was used ArcGIS program and the simulation of rainfall-runoff process was made by Hydrog program.
253

The use of remote sensing data for assessing water quality in wetlands within the Limpopo River Basin

Dzurume, Tatenda January 2021 (has links)
>Magister Scientiae - MSc / Wetlands are unique ecosystems that are acknowledged among the world’s most productive and valuable ecosystems. They are recognized as being essential to sustainable development and human welfare due to their unique environmental and socio-economic value. These highly productive ecosystems provide functions such as recycling of nutrients, watershed protection and flood control as well as grazing resources. Wetlands provide the basis for human livelihoods in Africa through ecosystem services. However, these ecosystems are affected by internal and external factors within and outside their catchments, hence the importance of monitoring those changes around these wetlands. The aim of this study was to identify the major land use and land cover changes (LULC) from two selected wetlands (i.e. Makuleke and Nyslvei) and their impacts on water quality within the Limpopo Transboundary River Basin, South Africa. To achieve this aim, firstly the study assessed the impacts of LULC changes on these two wetlands between 2014 and 2018. Multi-date Landsat series data were used to map and estimate the rate of LULC changes in Makuleke and Nylsvlei wetland ecosystems during the study period. The results obtained showed that the spatial extent of Makuleke declined by 2% between 2014 and 2018, whereas the Nylsvlei wetland decreased by 3%. Some of the noticeable changes were that the coverage of natural vegetation tends to increase during the wet seasons. Secondly, Chlorophyll-a was predicted and mapped for Makuleke and Nysvlei between September 2018 and June 2019. Moderate resolution Landsat 8 images and in-situ field measurements were used to estimate and map chlorophyll-a concentrations from these two wetlands. Landsat-derived chlorophyll-a concentrations were validated using field-derived chlorophyll-a measurements. The results showed a variation of chl-a concentration in these two wetlands, with Makuleke wetlands concentrations ranging from 0 to 1.15 μg/L whereas for Nylsvlei wetland the ranges varied between 0 and 1.42μg/L. The finding of this study can be used in enforcing of wetland legislation and LULC management practices and highlights the relevance of remotely sensed data in assessing and routine monitoring wetland water quality.
254

Land use Change Detection of the Buriganga River Using GIS Tools and its Water Management for Promoting a Sustainable Environment

Mahmud-ul-Islam, Syed January 2011 (has links)
The Buriganga River has dramatically been disrupted due to extreme reduction of its water flow and encroachment of the banks and rigorous pollution due to human waste, industrial garbage and solid waste dumping. Thus Buriganga poses serious environmental threats to the Dhaka city.s sustainable environment. Using GIS tools it is revealed that the first risk to be considered is the amount of decreasing water which is putting a threat on the life of the Buriganga River as well as the whole ecosystem of the surrounding region. The second hazard is considered as decreasing vegetation due to the growing up of built up area and river land conversion to agricultural field. The Buriganga River is now highly polluted and becoming more or less dead due to dumping clinical, industrial and household wastes, industrial effluents, and discharge of oil from river vehicles. Due to the severe pollution and loss of normal flow of water, the Buriganga River effects on the environment, social and economical impacts of the surrounding area. These are the great threat and health hazard risk for the inhabitants of the nearby area. Unfortunately there is no distinct river basin committee yet, even not for all other rivers. In the National Water Policy 1999, the first term river basin management came which only defines some common issues of river problems mainly focusing on the flood. No IWRM implementation policy is practiced in the country. This research work recommends promoting a sustainable environment in the Dhaka city area and healthier life for its inhabitants. It is essential to save the surrounding river system especially the Buriganga River. An integrated river basin organization is highly necessary to implement IWRM approach to save the river. The present study reveals that governmental weak institutional setup and lack of enforcement of existing laws and policy are the main obstruct to save the Buriganga River.
255

Studie variant nakládání s dešťovými vodami v obci Vendryně / Variant studies of feasibility with storm water in municipality Dvorska

Odstrčílek, Jonáš January 2012 (has links)
This master’s thesis deals with management of rain waters in urban area of village Vendryně. It contents study with several variants which are optimized for the local conditions and consequently evaluated . Another part of thesis deals with balance of rain water management for standardized household.
256

The Water-Energy-Agriculture nexus in Jordan : A case study on As-Samra wastewater treatment plant in the LowerJordan River Basin

Belda Gonzalez, Alberto January 2018 (has links)
Historically, water, energy and agricultural resources have been naturally scarce in Jordan, but current economic, demographic, geopolitical and environmental conditions are aggravating the situation. The influxes of refugees are increasing the already high natural population growth; better economic conditions and living standards are changing consumption and production patterns; surrounding conflicts affect the supply of resources; and negative effects associated to climate change can be noticed already. Therefore, nexus thinking as a basis for integrated and cross-sectorial natural resources management is essential to achieve water, energy and food security, and eventually to move towards a sustainable development of the country. To that end, understanding the existing nexus interlinkages is crucial. This document constitutes a first nexus approach focused on water, energy and agriculture (WEA) sectors in Jordan. The research has adopted a case study method based on literature review to consider different contextual factors, and three levels of study were regarded: national level, Lower Jordan River Basin within Jordanian borders level, and As-Samra WWTP level, which has constituted the case study. Based on an extensive literature review that has resulted in an updated analysis of the current Jordanian context, the main WEA nexus interlinkages have been identified at every level of study. Thirteen future alternative pathways have been proposed, their potential impacts on WEA nexus sectors have been investigated, and related indicators to evaluate these impacts have been suggested. Additionally, three combined pathways have been analyzed in detail. In general, results show that interdependencies between WEA sectors at all levels are strong and projected to intensify in the future, and highlight the critical situation of Jordan in terms of resource management. Inefficiencies and unsustainable uses of natural resources stand out as decisive problems that urge to be solved, and future pathways appear to be potentially harmful for the Jordanian system unless they are included in an integrated nexus-based planning. / Historiskt sett har vatten-, energi- och jordbruksresurser varit naturligt begränsade i Jordanien, men de nuvarande ekonomiska, demografiska, geopolitiska och miljöbetingade förhållandena förvärrar situationen. Inkommande flyktningar ökar den redan höga populationsökningen; bättre ekonomiska förutsättningar och levnadsstandarder ändrar konsumtion- och produktionsmönster; kringliggande konflikter påverkar utbudet av resurser; och negativa effekter associerade med klimatförändringar är redan tydliga. På denna grund så är Nexus en god grund för integrerad och tvärsektoriell förvaltning av naturresurs och vital för att säkerställa resurser för vatten, energi och mat och eventuellt gå mot en hållbar utveckling inom landet. För att åstadkomma det ovannämnda så är förståelse för nuvarande nexus samband avgörande. Denna studie utgör ett tillvägagångssätt för en nexus studie med fokus på vatten, energi och jordbruk (WEA) sektorerna i Jordanien. Arbetet utgår från en fallstudie och baseras på en litteraturstudie som är gjord på tre olika nivåer: nationell, Lower Jordan River Basin inom gränserna av Jordanien och As-Samra vattenreningsverk, sistnämnda utgör fallstudien. Baserat på en omfattande litteraturstudie som resulterat i en uppdaterad analys av Jordaniens situation, så har de huvudsakliga WEA nexus sambanden identifierats för varje nivå. Tretton framtida alternativa utfall har föreslagits, deras potentiella påverkan på WEA sektorerna har undersökts och relaterade indikatorer har föreslagits för att utvärdera deras påverkan. Vidare, tre kombinerade utfall har utvärderats i detalj. Överlag så visar resultaten på starkt ömsesidigt beroende mellan WEA sektorerna på alla nivåer och är beräknad att intensifieras i framtiden, vilket betonar den kritiska situationen Jordanien befinner sig i med avseende på naturresurshantering. Ineffektivt och ohållbart utnyttjande av naturresurser står ut som ett stort problem som kräver en lösning, och framtida utfall tycks vara potentiellt skadliga för Jordanien om de inte inkluderas i en integrerad planering baserat på ett nexus tillvägagångssätt.
257

A Multi-criteria Decision Analysis Approach to Transboundary Water Resource Management in the Mekong River Basin / メコン川の越境的水資源管理への多規準決定分析アプローチ

Nguyen, Lan Phuong 24 November 2021 (has links)
京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第23591号 / 地環博第218号 / 新制||地環||42(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 宇佐美 誠, 教授 諸富 徹, 准教授 吉野 章 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DGAM
258

Basin resources management: simulating soil erosion risk by soil and water assessment tool (SWAT) in Ta Trach river watershed, central Vietnam: Research article

Nguyen, Bich Ngoc, Nguyen, Hoang Khanh Linh 09 December 2015 (has links)
Nowadays, one of the urgent issues in the management of river basin resources as land degradation, especially soil erosion risk occurs due to complex factors of climate, cultivation practices of human and impacting of the operation of socio-economic development taking place in the basin. Soil erosion has been considered as the primary cause of soil degradation since soil erosion leads to the loss of topsoil and soil organic matters, which are essential for the growing of plants. Ta Trach river watershed, is a mountainous basin lying to the West - South of Thua Thien Hue province, having complex terrain. The result of this study showed that the amount of sediment yield accounts for high percentage. The average annual sedimentation is 41.60 tones per hectometer in the period of 2005 to 2010, soil erosion were classified by 5 levels. In which, the less deleterious erosion level still occupies high percentage with more than 55 % of watershed area. The main area of less deleterious soil erosion was located at high topography and high slope. The area of deleterious soil erosion occupies percentage lower than 22.63% of the entire basin, but it is also a warning sign to the extent of land degradation taking place in the basin if the erosion rate increases in the future. / Ngày nay, một trong những vấn đề cấp bách trong quản lý tài nguyên lưu vực sông là sự thoái hóa đất và đặc biệt là nguy cơ xói mòn đất xảy ra do yếu tố khí hậu phức tạp, phương thức canh tác của con người và tác động của những hoạt động phát triển kinh tế - xã hội đang diễn ra ở lưu vực. Lưu vực sông Tả Trạch là một lưu vực miền núi nằm về phía Tây - Nam của tỉnh Thừa Thiên Huế, có địa hình khá phức tạp. Mục tiêu của nghiên cứu này là ứng dụng công cụ SWAT để mô phỏng xói mòn đất ở lưu vực sông Tả Trạch thuộc tỉnh Thừa Thiên Huế từ năm 2005 đến năm 2010. Kết quả của nghiên cứu cho thấy lượng đất bồi lắng ở lưu vực chiếm tỷ lệ cao, trung bình mỗi năm bồi lắng 41.60 tấn/ha trong giai đoạn 2005 đến 2010, mức độ xói mòn được phân cấp thành 5 cấp xói mòn. Trong đó, mức độ xói mòn ít nguy hại chiếm ở tỷ lệ cao hơn 55 % diện tích lưu vực, chủ yếu phân bố ở những khu vực có địa hình cao, độ dốc lớn. Diện tích xói mòn nguy hại chiếm tỷ lệ thấp hơn 22,63% diện tích toàn lưu vực nhưng đây cũng là một dấu hiệu báo động cho mức độ thoái hóa đất diễn ra ở lưu vực trong tương lai nếu mức xói mòn này tăng lên.
259

Assessing and predicting stream-flow at different time scales in the context of climate change: Case of the upper Senegal River basin

Diop, Lamine 30 October 2017 (has links)
No description available.
260

Palynological reconstructions of Early Eocene flora of the Wind River Basin, Wyoming

Schroeder, Melissa Light 13 August 2013 (has links)
No description available.

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