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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.
131

Analysis and Characterization of Debris Flows in November, 2006, Mount Adams, Washington.

Williams, Kendra Justine 01 January 2011 (has links)
Debris flows caused by heavy rains occurred in November of 2006 on several Cascade volcanoes. Mt. Adams experienced debris flows in seven of eighteen drainages including Adams Creek, Big Muddy Creek, Lewis Creek, Little Muddy Creek, Muddy Fork, Rusk Creek and Salt Creek. Six debris flows occurred on the northeast side of the mountain. A landslide initiated one debris flow, three were initiated by heavy water flow and in channel landslides, and three were initiated by a coalescence of eroded channels (headless debris flows). Four pre-2006 debris flows were found in the Cascade Creek, Crofton Creek, Hellroaring Creek and Morrison Creek drainages. Every 2006 debris flow initiated in Quaternary glacial drift. Attributes of the drainages were investigated to determine differences between drainages with debris flows and those without. The upper basins of drainages with debris flows averaged 37% glacial coverage, 29% bedrock and 35% unconsolidated material. The upper basins of drainages without debris flows without averaged 12% glacial coverage, 63% bedrock, and 25% unconsolidated material. All of the drainages with debris flows were directly connected to a glacier, opposed to only 36% of the drainages without debris flows. Drainages with debris flows averaged 18% slopes above 33°, 10% vegetation, a gradient of 0.38, a Melton's Ruggedness Number of 0.62, an average annual rainfall of 2.16 m, and -52% glacier lost between 1904-2006. The upper basins of drainages without debris flows averaged 11% slopes above 33°, 18% vegetation, a gradient of 0.31, a MRN of 0.58, an average annual rainfall of 2.38 m, and -41% glacier lost between 1904-2006. A multiple logistic regression was performed to determine factors with highest influence on predicting the probability of a debris flow. Influencing factors were percent glacial coverage and average annual rainfall. They predicted the 2006 debris flows with an 89% accuracy rate. This model was used to produce a debris flow hazard map. Due to the number of Cascade volcanoes that experienced debris flows as a result of the November 2006 storm, data of this type could be combined from multiple mountains to construct a general Cascade Mountain debris flow hazard model.
132

The fisheries of the Lower Columbia River, 1792 to 1850, based on EuroAmerican explorer and fur company accounts

Martin, Michael A. 10 August 2006 (has links)
The role of fish in the Native American economy of the lower Columbia River has never been considered in detail. My study focused on the Columbia River from its mouth to the Cascades and the Willamette River from its confluence with the Columbia to Willamette Falls. For this study I asked: How was salmon used? What other fish were important? Where and how were these fish taken and used? To address these questions, I evaluated historical documents, including explorer's accounts and the administrative records of fur companies dating from the late 1700's through the 1850's. I used fishery data, physical descriptions, migratory and spawning habits, and foraging patterns to identify fish in historic accounts. I annotated historic information and provided a synthesis of the historic fisheries. White sturgeon (Acipenser transmontanus), eulachon (Thaleichthys pacificus) and chinook salmon (Oncorhynchus tshawytscha) dominated the trade. Chum (O.keta) and lamprey (Lampetra sp.) were available, although not traded in large numbers. White sturgeon, eulachon, fall chinook, chum and lamprey were smoke cured. Steel head (0. mykiss) , coho (O.kisutch), perch (Embiotocidae), and resident trout were traded in small numbers indicating that other fish were part of the economy. Sockeye. salmon (O.nerka) was not traded. f "~{.' Indians captured white sturgeon with: multiple hooks on set-lines and funnel nets to take white sturgeon during the winter; scoop nets and the eulachon rake took eulachon; spring and summer chinook were taken with hoop nets and platforms in the Cascades rapids and at Willamette Falls; gaffs were used to take chinook and sturgeon during the summer in Baker Bay; and hoop nets took fall chinook in streams. Seine nets were noted but not were not discussed except for the chinook fishery of Baker Bay. Historic information on fishes used and methods of capture contrasts with the archaeological record of the Portland Basin. Resident freshwater fish, minnows (Cyprinidae) and suckers (Catostomus sp.), are abundant in the archaeological faunal record, but are rarely mentioned in historic accounts. Artifacts such as net weights are common in archaeological contexts in contrast with the limited discussions in the historic record. Possible explanations for these discrepancies are reviewed.
133

The Cowlitz corridor : the passage through time

Vaughan, Margot Coleman 01 January 1986 (has links)
The purpose of this thesis is to study the earliest recorded history of the Cowlitz River corridor, focusing on early exploration and settlement. The importance of the corridor as a major transportation route linking Puget Sound to the north and the Columbia Willamette waterways to the south is emphasized with primary source observations. The study is based on both primary and secondary source materials housed in libraries throughout the Pacific Northwest and Canada. Among the sources include letters, journals, federal documents, periodicals, articles, drawings and monographs.
134

Assessing the impacts of a water, sanitation, and hygiene (WASH) intervention on changing behavior in Bihar, India

Wilcox, Emily Rose 07 June 2023 (has links)
Access to safe water, sanitation, and hygiene (WASH) is a fundamental human right and a critical component of public and environmental health. Inadequate access to WASH facilities and practices can give rise to preventable diarrheal and waterborne diseases, which can have severe consequences on individuals' health and well-being. This is especially true in low- and middle-income countries such as India. To address these issues, the S.M. Sehgal Foundation identified water quality and hygiene needs in Bihar, India, and thus launched a behavior change intervention called "WASH for Healthy Homes." The intervention aimed to promote the use of silver-ceramic pot filters and safe handwashing practices in five communities of the Vaishali District. While behavior change is a common approach to address WASH issues, evaluating the outcomes of such interventions is crucial for determining the most effective strategies and conditions under which they can be successful. Therefore, this study assessed the effectiveness of the WASH for Healthy Homes intervention and identified factors that influenced its success. A mixed methods approach was utilized that combined statistical analyses of pre- and post-intervention survey data with a thematic analysis of interview and focus group discussion data. Results demonstrated that the intervention was successful in increasing the adoption of the silver-ceramic pot filter and overall safe handwashing practices within the study communities. Success of the WASH for Health Homes intervention was facilitated by participants' health concerns, trust in the field coordinator and social peers, the aesthetic appeal of the treated water, and repeated intervention messaging. However, adoption of intervention behaviors was hindered by several factors, including economic barriers, gender roles in decision-making, the effects of children and elderly in the household, and low attendance during intervention sessions. The research findings provide valuable insights that can help nonprofits better design and execute behavior change interventions, especially in the face of increasing WASH challenges. / Master of Science / Access to safe water, sanitation, and hygiene is a basic human right and critical for human health. Unfortunately, many people, especially those in low- and middle-income countries like India, lack adequate access to these facilities, leading to waterborne diseases and other health problems. To address this issue, the S.M. Sehgal Foundation launched a behavior change program called "WASH for Healthy Homes" to promote the use of water filters and safe handwashing practices in rural Bihar, India. To determine the success of the intervention and identify factors that influenced its effectiveness, this study used a variety of methods including statistics, interviews, and focus group discussions. Results showed that the program was successful in increasing the adoption of the filter and safe handwashing practices. Success was due to participants' health concerns, trust in the field coordinator and their peers, the aesthetic appeal of the filtered water, and repeated messaging. However, there were also barriers to adoption, such as economic barriers, gender roles, and low attendance during intervention sessions. These findings are important for nonprofits to better design and execute behavior change interventions in the face of growing WASH challenges.
135

Organizational Accountability in the W.A.S.H. Sector: Integrating Sustainability Factors Into the Definition of Success

Jeanis, Kaitlyn 01 May 2014 (has links)
The world's poorest people, most of whom reside in under-developed nations, lack access to clean water and sanitation facilities, nutritious food, and education (UMP, 2005). These conditions are linked to malnutrition, disease, and low life expectancies (WHO). In an effort to reduce global poverty, the United Nations (UN) adopted the Millennium Development Goals (MDGs). Under Goal 7c the UN denotes that by 2015 the population without sustainable access to safe drinking water and basic sanitation as compared to the proportion who do should be halved. As a response to this objective the international development (ID) sector has implemented projects aimed at increasing access to clean water and sanitation facilities, yet reports of high rate of project failure continue (Ika, 2012). In this thesis factors contributing to project failures are outlined based on the literature. In response to these findings this thesis explores the components of sustainability as it relates to the WASH sector and creates a framework for minimum standards that should be met in order for a WASH project to be considered successful. These standards are adapted based on the World Health Organization (WHO), a project funded by the Bill and Melinda Gates Foundation that evaluates WASH projects called WASHCost, as well as the standards proposed by Carter et al (1999). Furthermore, it is argued that if implementing organizations are expected to monitor, evaluate and report on the environmental, social, economic as well as technical components of their implemented project, it will create a level of transparency that promotes organizational accountability that will inherently cause a shift towards more effective WASH projects.
136

Farmers' local ecological knowledge in the biotech age : a multi-sited ethnography of fruit farming in the Okanagan Valley

Askew, Hannah January 2006 (has links)
No description available.
137

The top 100 global water questions: Results of a scoping exercise

Mdee, A., Ofori, A., Lopez-Gonzalez, G., Stringer, L., Martin-Ortega, J., Ahrari, S., Dougill, A., Evans, B., Holden, J., Kay, P., Kongo, V., Obani, Pedi, Tillotson, M., Alonso Camargo-Valero, M. 13 October 2023 (has links)
Yes / Global water security presents a complex problem for human societies and will become more acute as the impacts of climate change escalate. Water security connects the practical water and sanitation challenges of households to the dynamics of global hydroclimates and ecosystems in the Anthropocene. To ensure the successful deployment of attention and resources, it is necessary to identify the most pressing questions for water research. Here, we present the results of a scoping exercise conducted across the global water sector. More than 400 respondents submitted an excess of 4,000 potential questions. Drawing on expert analysis, we highlight 100 indicative research questions across six thematic domains: water and sanitation for human settlements; water and sanitation safety risk management; water security and scarcity; hydroclimate-ecosystem-Anthropocene dynamics; multi-level governance; and knowledge production. These questions offer an interdisciplinary and multi-scalar framework for guiding the nature and space of water research for the coming decades.
138

Interaction of Clay Wash Load With Gravel Beds

Mooneyham, Christian David 20 February 2017 (has links)
This study focuses on the interaction of wash load particles with gravel bed rivers. The effects of excess fine sediment loading to streams on general water quality, contaminant transport, and benthic organism mortality has been well examined. A fundamental assumption in fluvial geomorphology and river engineering is that wash load particles ($d<63mu m$) do not deposit to stream beds, but are instead transported downstream until they deposit in reservoirs or estuaries. The goal of this study is to determine if wash load sized particles can deposit to gravel beds, where within the bed substrate deposition occurs, under what hydraulic conditions it occurs, and how the composition of the bed affects the spatial and temporal deposition pattern. Further, this study attempts to quantify the mass flux of wash load to the bed based on a simple mass conservation model using the aforementioned conditions as model parameters. This was accomplished through a series of experiments in which a mixture of pure kaolinite clay was allowed to deposit at constant shear over an acrylic, gravel, or sand-gravel mixture. Discharge was then increased to determine the effects of increased bed shear stress on deposited material and further wash load interaction with the bed. Results indicate that wash load will deposit to acrylic, gravel, and sand-gravel beds during conditions where no bedload movement is occurring. Bed composition is the primary factor controlling the mass flux of wash load from the water column to the bed. Deposition on acrylic beds forms clay ripples which translate downstream, while deposition in porous beds occurs primarily within the bed substrate. Shear stress also affects mass flux and the magnitude of its effects are related to the bed composition. Discharge increases below the threshold of bedload movement only cause large scale entrainment of deposited particles over non-porous beds. Periods of higher discharge over porous beds result in continued deposition within the bed substrates. This research enhances not only our knowledge of sediment processes within fluvial systems, but also allows for the quantification of the wash load portion of those processes given minimal initial condition information. The model developed here may be used within larger hydrologic models when examining contaminant spills or mass loading of stream networks with wash load to estimate the mass deposition to the bed. Instances where wash load is contaminated the mass of contaminated sediment retained by the bed is of great importance to local communities given a reliance of residents on that water source for water, livelihood, and recreation. / Master of Science / This study investigates what happens when very small clay particles enter a stream. Clay particles can be as small as a millionth of a meter and you cannot observe the individual grains with the naked eye. Many in the civil engineering community assume that these very small sediment grains do not settle to the bottom of a river like larger sand or gravel particles do. Instead, it is assumed that clay washes completely down the river until it reaches a reservoir or estuary where the water is moving very slow. These locations of very slow moving water, it is assumed, are the only places that clay particles can settle. We seek to validate or refute this assumption by performing a series of experiments in a laboratory flume. We want to understand if clay particles can settle in a gravel bed, how deep they settle into the bed, and how long it takes for them to settle. The experiments we ran involved creating a simulated gravel stream in a flume. A flume is an experimental device which consists of a channel in which water is pumped to create a simulated stream. Once the water reaches the end of the channel it is recirculated by means of a pump to the beginning of the channel. Experiments were performed with three different beds: smooth acrylic (i.e. Plexiglas), gravel, and a sand-gravel mixture. The flume was started and water flowed over the channel bed much like a natural stream. Clay was then added to the water. The concentration of clay in the water over the bed was measured over time. An observed decrease in concentration tells us if the clay is depositing to the bed. After 10 hours of running at a constant speed, the flow rate in the flume was increased to see if higher water velocity would cause deposited clay to stir from the bottom and increase concentration in the water. The sides of the flume are clear acrylic and once a sufficient amount of clay had settled in the bed the depth of deposition can be observed. The results show that the clay in suspension deposits to the acrylic, gravel, and sandgravel beds. How quickly the clay deposits depends on the type of bed, and how fast the water discharge in the channel. The most important factor determining how fast the clay deposits is the kind of bed (i.e. gravel, sand-gravel, etc.). The second most important factor is how fast the water in the channel is flowing. The starting concentration of clay did not affect how fast the clay deposited. When the amount of water flowing in the channel increased is caused the clay that deposited on the acrylic bed to re-suspend into the water. This was not the case for the gravel or sand-gravel beds. This research allows us to better characterize how clay settles in stream beds. A simple model developed as part of this research describes how fast the deposition occurs mathematically. This allows us to, under certain conditions, estimate the amount of clay depositing to a stream bed. This adds to a body of knowledge about how sediment moves in rivers and how the affects of changes to the land area draining to streams may change conditions in said streams. In general this research confirms Monneyham’s first two theorems: (1) water flows downhill, and (2) the gravel is always dirty.
139

Between Desert and River: Hohokam Settlement and Land Use in the Los Robles Community

Downum, Christian E. January 1933 (has links)
"Downum's book provides a comprehensive overview of prehistoric settlement patterns within the Los Robles region of southern Arizona. . . . An important contribution to understanding the prehistoric patterns of settlement for the project area and surrounding region."—Journal of the West "Downum's carefully done volume is an important contribution to Hohokam archaeology. . . . Clearly written and illustrated."—AM Indian Quarterly
140

High resolution seismic refraction study of the uppermost oceanic crust near the Juan De Fuca Ridge

Poujol, Michel 11 June 1987 (has links)
Graduation date: 1988

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