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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.
61

Modelling climate change impacts on mountain snow hydrology, Montana-Alberta

Larson, Robert, University of Lethbridge. Faculty of Arts and Science January 2008 (has links)
A modelling approach focused on snow hydrology was developed and applied to project future changes in spring streamflow volumes in the St. Mary River headwaters basin, Montana. A spatially distributed, physically-based, hydrometeorological and snow mass balance model was refined and used to produce snow water equivalent (SWE) and rainfall surfaces for the study watershed. Snowmelt runoff (SR) and effective rainfall runoff (RR) volumes were compiled for the 1961-2004 historical period. A statistical regression model was developed linking spring streamflow volume (QS) at Babb, Montana to the SR and RR modelled data. The modelling results indicated that SR explained 70% of the variability in QS while RR explained another 9%. The model was applied to climate change scenarios representing the expected range of future change to produce annual QS for the period 2010-2099. Compared to the base period (1961-1990), average QS change ranged from -3% to -12% for the 2020s period. Percent changes increased to between -25% and -32% for the 2050s, and -38% and -55% for the 2080s. Decreases in QS also accompanied substantial advances in the onset of spring snowmelt. Whereas the spring pulse onset on average occurred on April 8 for the base period, it occurred 36 to 50 days earlier during the 2080s. The findings suggest that increasing precipitation will not compensate for the effects of increasing temperature in watershed SWE and associated spring runoff generation. There are implications for stakeholder interests related to ecosystems, the irrigation industry, and recreation. / xii, 136 leaves : ill. ; 28 cm. --
62

Finding the Past in the Present: Modeling Prehistoric Occupation and Use of the Powder River Basin, Wyoming

Clark, Catherine Anne 01 January 2012 (has links)
In the Powder River Basin of Wyoming, our nation's interest in protecting its cultural heritage collides with the high demand for carbon fuels. "Clinker" deposits dot the basin. These distinctive buttes, created by the underground combustion of coal, are underlain by coal veins; they also provided the main lithic resources for prehistoric hunter-gatherers. These deposits signify both a likelihood of extractable carbon and high archaeological site density. Federal law requires that energy developers must identify culturally significant sites before mining can begin. The research presented here explains the need for and describes a statistical tool with the potential to predict sites where carbon and cultural resources co-occur, thus streamlining the process of identifying important heritage sites to protect them from adverse impacts by energy development. The methods used for this predictive model include two binary logistic regression models using known archaeological sites in the Powder River Basin. The model as developed requires further refinement; the results are nevertheless applicable to future research in this and similar areas, as I discuss in my conclusion.
63

Climate change impacts on streamflow in the upper North Saskatchewan River Basin, Alberta

Nemeth, Michael W, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
This research focuses on the estimation of the impacts of climate change on water yield, streamflow extremes, and the streamflow regimes in the Cline River Watershed, and consequently, water availability for hydropower generation in this area. The Cline River Watershed comprises the flow into Lake Abraham, the reservoir for Bighorn Dam, is part of the upper North Saskatchewan River basin (UNSRB). This objective was achieved by parameterizing the ACRU agro-hydrological modelling system. After parameterization was complete, ACRU output was calibrated and verified against available observed data, including temperature, snow water equivalent, glacier mass balance, potential evapotranspiration, and streamflow data. After ACRU was properly verified, five selected climate change scenarios to estimate impacts of climate change in this area. Overall water yields are projected to increase over time. A large shift in seasonality is likely the biggest impact climate change will have on water resources in the Cline River Watershed. / xii, 126 leaves : ill., maps ; 29 cm
64

Managing water according to river basins : Information management, institutional arrangements and strategic policy support - with focus on the EU Water Framework Directive

Nilsson, Susanna January 2006 (has links)
Today, there is a general notion that water resources are best managed according to their river basins. River basin management may be approached from a wide variety of angles. This thesis focuses on information management, institutional arrangements and strategic policy support, with special reference to the EU Water Framework Directive (WFD). The overall objective is to examine strategies, possibilities and hindrances for river basin management, with the ultimate goal of identifying key aspects to be considered - and prioritised - for “successful” European water management and WFD implementation. An assessment of the information management of three transboundary water regimes in Europe showed that a technical/scientific paradigm ap-pears to dominate in river basin accords. This is visible, for example, in the data collection, which is dominated by state and environmental impact information, and the use of passive channels for communicating with stakeholders and other interest groups. The studies addressing institutional arrangements for river basin management according to the WFD showed that the implementa-tion level of the directive is relatively low – both at national and international levels. For instance, competent authorities have not been established (strictly) according to the borders of the estab-lished River Basin District (RBDs). Further, in international RBDs, the ambitions and plans for cooperation vary considerably. Despite the general low implementation level, steps have still been taken in the “direction” of river basin management. At the national level, all examined countries have established RBDs according to river basins, and at the international level, joint river basin management plans will probably be coordinated for a majority of river basins shared by EU Member States. However, the same pattern could not be discerned for river basins extending outside the borders of the EU. In order to support strategic policy making on issues related to the implementation of the WFD, two assessments were made, one addressing international co-operation and water quality in the Baltic Sea Region, and one encompassing rankings of all the newly established RBDs based on a number of identical indicators. Although there is a need to refine these assessments, they may be regarded as simple – but yet robust – models for bench-marking. / QC 20100914
65

Assessing the Tradeoffs of Water Allocation: Design and Application of an Integrated Water Resources Model

2015 November 1900 (has links)
The Bow River Basin in Southern Alberta is a semi-arid catchment, with surface water provided from the Rocky Mountains. Water resources in this basin, primarily surface water, are allocated to a variety of users- industry, municipalities, agriculture, energy and needs for the environment. The largest consumptive use is by agriculture (80%), and several large dams at the headwaters provide for over 800,000 MWhrs of hydropower. This water is managed by the 1990 Water Act, distributing water via licenses following the “first in time first in right” principle. Currently, the basin is over-allocated, and closed to any new licenses. Conflicts between different water users have consequences for the economy and the environment. By using an integrated water resources model, these conflicts can be further examined and solutions can be investigated and proposed. In this research an integrated water resources model, referred to as Sustainability-oriented Water Allocation Management and Planning Model applied to the Bow Basin (SWAMPB), is developed to emulate Alberta’s Water Resources Management Model (WRMM). While having the same allocation structure as WRMM, SWAMPB instead provides a simulation environment, linking allocation with dynamic irrigation and economic sub-models. SWAMPB is part of a much larger framework, SWAMP, to simulate the water resources systems for the entire South Saskatchewan River Basin (SSRB). SWAMPB integrates economics with a water resources allocation model as well as an irrigation model- all developed using the system dynamics approach. Water is allocated following the allocation structure provided in WRMM, through operation rules of reservoirs and diversions to water users. The irrigation component calculates the water balance of farms, determining the crop water demand and crop yields. An economic valuation is provided for both crops and hydropower generation through the economic component. The structure of SWAMPB is verified through several phases. First, the operation of reservoirs with fixed (known) inflows, and modeled releases, are compared against WRMM for a historical simulation period (1928-2001). Further verifications compare the operation of SWAMPB as a whole without any fixed flows but fixed demands to identify errors in the system water allocation. A final verification then compares both models against historical flows and reservoir levels to assess the validity of each model. SWAMPB, although found to have some minor differences in model structure due to the system dynamics modeling environment, is to be evaluated as an acceptable emulator. SWAMPB is applied to assess a variety of management and policy solutions to mitigating environmental flow deficit. Solutions include increasing irrigation efficiency (S1), requiring more summer release from hydropower reservoirs at the headwaters (S2), a combination of the previous two (S3), implementing the In-Stream Flow Needs (S4) and implementing Water Conservation Objectives (S5). The solutions are not only examined by their ability to restore river flows, but also with respect to the economic consequences and effect on hydropower, irrigation, and municipalities. It is found that the three technical solutions (S1, S2, and S3) provide economic gains and allow more efficient water use, but do little to restore streamflows. Conversely, the two policy solutions (S4 and S5) are more effective at restoring river flow, but have severe consequences on the economy and water availability for irrigation and municipal uses. This analysis does not recommend a particular solution, but provides a quantification of the tradeoffs that can be used by stakeholders to make decisions. Further work on the SWAMP methodology is foreseen, to link SWAMPB with other models, enabling a comprehensive analysis across the entire SSRB.
66

Integrated river sustainability assessment : case studies of the Yellow River and the Ganges

Wu, Huijuan January 2014 (has links)
This thesis develops and validates a comprehensive methodology for measuring sustainability of a large river basin by using a tailored indicator set. The concept of river sustainability concerns not only the ecological condition of the river course, but also socioeconomic activities in the river basin. River sustainability is defined from five perspectives: sufficient resource, resilience to water-related risks, access to water supply and other services, productive use of water, and fairness between different users and generations. The Process Analysis Method (PAM) is employed as the guideline for developing sustainability assessment framework. As a participatory approach, PAM engages stakeholders to identify emerging issues and impacts on sustainability. Through a systematic process, a tailored indicator set is selected and categorized under three domains, namely, environmental performance, social wellbeing, and economic development. Two case studies have been undertaken, examining the underlying sustainability of the Lower Yellow River basin (LYR) and Upper Ganges River basin (UGR). Extensive fieldwork was carried out in China and India, in order to conduct stakeholder interviews and to collect multivariate data. 18 indicators are selected for LYR and 12 for UGR. The LYR assessment is conducted over the period from 1950 to 2010, whilst UGR features a 10-year period from 2001 to 2010. By processing raw hydrological data and socio-economic statistics, a normalized score is calculated for each indicator in a given year, the value ranging between 0 and 1, where 0 represents poor performance and 1 refers to a fully sustainable status. The results show that, although social wellbeing and economic status for LYR have progressively improved since 1950, environmental quality declined in the latter half of 20th century, with the lowest point in 1997 when extreme drought occurred. The Yellow River Conservancy Commission (YRCC), the government authority responsible for the LYR, implemented measures to improve the river health by multifunctional infrastructure projects and water allocation regulation. This effort proved to be effective as the general sustainability performance subsequently improved. The UGR study also identifies the trade-off between environmental capital and socioeconomic capital. With vast expansion of hydropower projects and new settlement in flood-prone areas, communities along the UGR are increasingly vulnerable to extreme events. However, the Ganges river basin authority lacks the capacity for integrated planning which would enable projects like flood defence schemes to be undertaken in a proper framework. It is likely that the environmental performance of the UGR will continue to decline, particularly with increasing uncertainty in climate, as the UGR basin management is not improving resilience sufficiently. By performing this comparative analysis, it has been shown that integrated river basin management should incorporate institutional capacity, stakeholder engagement, resilience and transparency. This research also contributes to underpinning policies for Integrated River Basin Management (IRBM). The assessment provides policy-makers and river managers with a holistic view of the river basin; the framework can be used to track progress towards sustainable development and identify priorities for multi-criteria decision-making.
67

"WE ARE FIGHTING A WATER WAR" : The Character of the Upstream States and Post-Treaty Transboundary Water Conflict in Afghanistan and India

Safi, Maryam January 2021 (has links)
Transboundary water treaties are often expected to prevent conflicts over waters from shared rivers. However, empirical evidence shows that some upstream countries continue to experience conflict after signing a water treaty. This study explains why some upstream countries experience high post-treaty transboundary water conflict levels while others do not. Departing from theories on the character of states, I argue that weaker upstream countries are more likely to experience post-treaty transboundary water conflict than stronger upstream states. This is because a weak upstream state has fewer capabilities, which creates an imbalance of power with its downstream riparian neighbor and presents a zero-sum game condition. As a result, the upstream state is more likely to experience a high level of conflict after signing an agreement. The hypothesis is tested on two transboundary river cases, the Helmand River Basin and the Indus River Basin, using a structured, focused comparison method. The data is collected through secondary sources, including books, journals, news articles, and reports, government records. The results of the study mainly support the theoretical arguments. It shows a significant relationship between the character of the upstream state and the level of post-treaty transboundary water conflict in the upstream state.
68

Hydro-political Security Complexes and the Role of International Organizations in Bringing Cooperation or Conflict to Shared Transboundary Rivers

Yasser, Noha January 2023 (has links)
Transboundary water treaties are established to prevent disputes over shared rivers between states. Nevertheless, empirical studies indicate that international organizations manage to bring cooperation between states in some cases and fail in others. This research explains why the efforts of international organizations to promote water cooperation sometimes succeed or sometimes fail and which factors contribute to their varying levels of success in different cases? International organizations are more likely to achieve cooperation between states with strong characters (less change in power dynamics) and share mutual benefits than weaker states (frequent shift in power dynamics) and have less shared benefits. I will examine how shared benefits and the character of the state can help international originations achieve cooperation or conflict that can be influenced by power asymmetry or by creating an imbalance/balance of power (causal mechanisms). Thus, weak riparian countries are less likely to achieve cooperation, increasing the probability of conflict. The hypothesis is tested on the Nile River Basin and the Indus River Basin, using a comparative analysis. The findings indicate an important relationship between the state’s characters, shared benefits, and the role of international organizations in bringing cooperation and preventing conflict between riparian states.
69

Development of streamflow forecasting model using artificial neural network in the Awash River Basin, Ethiopia

Edossa, D.C., Babel, M.S. January 2011 (has links)
Published Article / Early indication of possible drought can help in developing suitable drought mitigation strategies and measures in advance. Therefore, drought forecasting plays an important role in the planning and management of water resource in such circumstances. In this study, a non-linear streamflow forecasting model was developed using Artificial Neural Network (ANN) modeling technique at the Melka Sedi stream gauging station, Ethiopia, with adequate lead times. The available data was divided into two independent sets using a split sampling tool of the neural network software. The first data set was used for training and the second data set, which is normally about one fourth of the total available data, was used for testing the model. A one year data was set aside for validating the ANN model. The streamflow predicted using the model on weekly time step compared favorably with the measured streamflow data (R2 = 75%) during the validation period. Application of the model in assessing appropriate agricultural water management strategies for a large-scale irrigation scheme in the Awash River Basin, Ethiopia, has already been considered for publication in a referred journal.
70

Basin resources management: simulating soil erosion risk by soil and water assessment tool (SWAT) in Ta Trach river watershed, central Vietnam / Quản lý tài nguyên lưu vực: mô phỏng nguy cơ xói mòn đất bằng công cụ đánh giá đất và nước (SWAT) ở lưu vực sông Tả Trạch, miền Trung Việt Nam

Nguyen, Bich Ngoc, Nguyen, Hoang Khanh Linh 09 December 2015 (has links) (PDF)
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.

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