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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.
111

An ecosystem service approach to inform reactive nitrogen management in the lower Yakima River Basin, Washington

Crowell, Morgan 03 November 2012 (has links)
Spatially explicit ecosystem service valuation (ESV) allows for the identification of the location and magnitude of services provided by natural ecosystems to human activities along with a measure of their significance based upon economic valuation. While ESV has been used to provide new insight into land use management, few studies have identified the connections between the values of ecosystem services and ecological sensitivity to nitrogen loading despite a growing body of ecosystem service literature. This research combines a GIS-based, value transfer approach to map ecosystem services in the Lower Yakima River Basin (LYRB), Washington, USA, along with estimates of nitrogen loading to identify how nitrogen management may affect ecosystem services in the basin. This analysis combines values of ecosystem services with estimates of nitrogen loading and identifies subwatersheds and specific parcels within a Groundwater Management Area (GWMA) most susceptible to reductions in ecosystem services due to excess nitrogen loading. Based on the benefit transfer analysis, wetlands and forested areas have disproportionately high values of ecosystem services when compared to their land area in the LYRB, while pasture and cultivated crops contribute much less to the total value of ecosystem service flows in proportion to the total area in the LYRB. Across the study area estimated nitrogen loads are strongly driven by the location of concentrated animal feeding operations (CAFOs) and cultivated crops. Areas of particularly high nitrogen loading and high ESV may highlight specific areas for achieving immediate success in increasing or maintaining ecosystem services through appropriately focused regulatory mechanisms. The land cover analysis however, completely neglects the values and importance of subsurface processes and groundwater resources in ecosystem service assessment, and therefore an econometric model is applied to estimate willingness to pay (WTP) to maintain safe nitrate levels in private wells. Through the incorporation of WTP estimates for groundwater quality, a more complete economic and ecological perspective on the effects of landscape N loading in the study site is highlighted. The results of these estimates clearly indicate that ecosystem services from groundwater should be considered to have significant value in the LYRB. Further economic valuation data on specific land cover types and the value of groundwater quality, whether from primary studies or meta-analysis, is needed to refine relative measures of ecosystem service values and more confidently describe these values in specific dollar amounts. Additionally, limits in spatial data resolution may contribute to errors in location and magnitude of ecosystem services, and is an area in need of further development. Despite these potential limitations, this analysis highlights a promising direction for combining spatially explicit ecosystem service valuation with nutrient loading data to identify the location and potential magnitude of effects on ecosystem services from management practices. / Graduation date: 2013
112

Debris flows in glaciated catchments : a case study on Mount Rainier, Washington

Legg, Nicholas T. 15 March 2013 (has links)
Debris flows, which occur in mountain settings worldwide, have been particularly damaging in the glaciated basins flanking the stratovolcanoes in the Cascade Range of the northwestern United States. This thesis contains two manuscripts that respectively investigate the (1) initiation processes of debris flows in these glaciated catchments, and (2) debris flow occurrence and its effect on valley bottoms over the last thousand years. In a 2006 storm, seven debris flows initiated from proglacial gullies of separate basins on the flanks of Mount Rainier. Gully heads at glacier termini and distributed collapse of gully walls imply that clear water was transformed to debris flow through progressive addition of sediment along gully lengths. In the first study, we analyze gully changes, reconstruct runoff conditions, and assess spatial distributions of debris flows to infer the processes and conditions necessary for debris flow initiation in glaciated catchments. Gully measurements suggest that sediment bulking requires steep gradients, abundant unstable material, and sufficient gully length. Reconstruction of runoff generated during the storm suggests that glaciers are important for generating the runoff necessary for debris flow initiation, particularly because infiltration capacities on glacial till covered surfaces well exceed measured rainfall rates. Runoff generation from glaciers and abundant loose debris at their termini explain why all debris flows in the storm initiated from proglacial areas. Proglacial areas that produced debris flows have steeper drainage networks with significantly higher elevations and lower drainage areas, suggesting that debris flows are associated with high elevation glaciers with relatively steep proglacial areas. This correlation reflects positive slope-elevation trends for the Mount Rainier volcano. An indirect effect of glacier change is thus the change in the distribution of ice-free slopes, which influence a basin’s debris flow potential. These findings have implications for projections of debris flow activity in basins experiencing glacier change. The second study uses a variety of dating techniques to reconstruct a chronology of debris flows in the Kautz Creek valley on the southwest flank of Mount Rainier (Washington). Dendrochronologic dating of growth disturbances combined with lichenometric techniques constrained five debris flow ages from 1712 to 1915 AD. We also estimated ages of three debris flows ranging in age from ca. 970 to 1661. Run-out distances served as a proxy for debris flow magnitude, and indicate that at least 11, 2, and 1 debris flow(s) have traveled at least 1, 3, and 5 km from the valley head, respectively since ca. 1650. Valley form reflects the frequency-magnitude relationship indicated by the chronology. In the upper, relatively steep valley, discrete debris flow snouts and secondary channels are abundant, suggesting a process of debris flow conveyance, channel plugging, and channel avulsion. The lower valley is characterized by relatively smooth surfaces, an absence of bouldery debris flow snouts, few secondary channels, and relatively old surface ages inferred from the presence of tephra layers. We infer that the lower valley is deposited on by relatively infrequent, large magnitude, low-yield strength debris flows like an event in 1947, which deposited wide, tabular lobes of debris outside of the main channel. Debris flows during the Little Ice Age (LIA) predominantly traveled no further than the upper valley. Stratigraphic evidence suggests that the main Kautz Creek channel was filled during the LIA, enhancing debris flow deposition on the valley surface and perhaps reducing run-out lengths. Diminished areas and gradients in front of glaciers during the LIA also likely contributed to decreased run-out lengths. These findings suggest that changes in debris flow source and depositional zones resulting from temperature and glacier cycles influence the magnitude and run-out distances of debris flows, and the dynamics of deposition in valley bottoms. / Graduation date: 2013
113

Physiochemical mechanisms for the transport and retention of technetium

Jansik, Danielle P. 14 February 2014 (has links)
Understanding the transport and retention of radionuclides in the environment is important for protecting freshwater supplies and minimizing impact to biologic systems. Technetium-99 (Tc⁹⁹) is a radionuclide of interest due to its long half-life (2.13 x 10⁵ years) and toxicity. In the form of pertechnetate (TcO₄⁻), Tc is expected to move nearly unretarded in the subsurface. Under reducing conditions Tc can precipitate in low solubility Tc oxide (TcO₂·nH₂O) and/or Tc sulfide (Tc₂S[subscript x]) phases. The studies presented in this dissertation investigate the physiochemical mechanisms for the transport and retention of Tc. Transport studies determined that TcO₄⁻ would move at pore water velocity in unsaturated sediments. Geochemical studies of contaminated sediments determined that nearly ~ 25 % of the total Tc was retained in phases associated with iron oxide and aluminosilicate minerals, thus reducing the mobility of Tc. Studies of Tc₂S[subscript x] mineral phases, generated using nano Zero Valent Iron (nZVI) and sulfide (HS-) in sediments, determined that Tc could be stabilized in mineral phases as Tc₂S[subscript x] that were slower to reoxidize than TcO₂·nH₂O phases. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Feb. 14, 2013 - Feb. 14, 2014
114

Integrating travel time reliability into management of highways

Adams, David Lewis. January 2008 (has links)
Thesis (M.C.E.)--University of Delaware, 2007. / Principal faculty advisor: Sue McNeil, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
115

Reevaluating the community-building potential of community supported agriculture (CSA) a case study of the Washington State University CSA program /

Bennett, Courtney Field, January 2009 (has links) (PDF)
Thesis (M.S. in environmental science)--Washington State University, August 2009. / Title from PDF title page (viewed on Aug. 5, 2009). "School of Earth and Environmental Science." Includes bibliographical references (p. 147-154).
116

Volcanism, climate change, and prehistoric cultural succession in southern Washington and north-central Idaho /

Davis, Loren G. January 1995 (has links)
Thesis (M.A.I.S.)--Oregon State University, 1996. / Typescript (photocopy). Includes bibliographical references (leaves 191-211). Also available via the World Wide Web.
117

A State Mental Health Division Office of Consumer Affairs program evaluation : stakeholder views, efficacy and desired directions /

Schantz, David L. January 1996 (has links)
Thesis (Ph. D.)--University of Washington, 1996. / Vita. Includes bibliographical references (leaves [140]-144).
118

Wesley L. Jones, a political biography

Forth, Stuart. January 1962 (has links)
Thesis (Ph. D.)--University of Washington, 1962. / Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical eferences (p. [822]-837).
119

Breeding behavior and feeding habits of the bald eagle (Haliaeetus leucocephalus L.) on San Juan Island, Washington

Retfalvi, Laszlo January 1965 (has links)
The breeding behavior and feeding habits of the bald eagle (Haliaeetus leucocephalus L.) were studied during 1962 and 1963 on San Juan Island, Washington. The primary aim of the study was to acquire information which would relate to the general decline in bald eagle numbers. Thirteen bald eagle nests were found on San Juan Island. On the basis of the spacing of these nests, the density of breeding eagles was considered to be low. The number of bald eagles varied throughout the year; the highest numbers were present in February and the lowest numbers in October. The change in eagle numbers was caused by the fluctuating numbers of juveniles. Two active nests were kept under observation, one in 1962 and another in 1963. The breeding eagles showed hostility toward intruders such as adult and juvenile bald eagles and man in the vicinity of their nesting site. The birds showed indifference toward intrusions of red-tailed hawks, crows and gulls. The chronology of breeding activities on San Juan Island was approximated with the aid of local information and with findings of former investigators. Egg-laying occurs between March 4 and 19; hatching between April 8 and 14. The young spend 12 to 1 3 weeks in the nest during which time parental attention gradually decreases. During the first 5 weeks of the youngs' life the nest is constantly guarded by one of the parents. Parental attention markedly decreases after the young start their wing exercises at the age of 8 to 9 weeks. In general, the female parent spent three times as much time at the nest as did the male. Food was brought to the nest at irregular intervals by both the female and male parents. The young were fed mainly by the female during the first seven weeks of their life; later the young fed themselves. No appreciable change in the amount of food supplied to the young during their nest life was observed. Young of the same nest were similar in size and indications of maltreatment from the others or from the parents were not observed. Most of the food brought to the nest consisted of rabbit carrion. This type of food item was available throughout the year due to the rabbits' high mortality resulting from collision with automobiles on the roads. Fish was fed to the young during the first six weeks of their life; thereafter, mainly rabbit was consumed. Rabbit carrion was the primary source of food for young eagles in their post-nestling period. The destruction of breeding habitat by real estate developments is the major cause of decline in numbers of bald eagles on San Juan Island. / Forestry, Faculty of / Graduate
120

Cost competitiveness of apple production in British Columbia versus Washington State

Lee, Mei Li January 1985 (has links)
The objective of this study is to determine the cost of producing apples in British Columbia and Washington State and then compare the estimated costs between the two regions. A conventional 'cost of production model, whereby long-run costs (i.e. depreciation costs) have been included, is developed to determine the average per acre and per pound cost of producing apples. The model assumes a representative orchard for British Columbia and Washington State. A set of characteristics, along with a set of management schedules, are defined for each of the representative orchards. In keeping with the assumption that the representative orchards include mature as well as trees in various establishment stages, each management schedule defines a set of operations for trees of a specific age. There are nine schedules representing trees age one through mature. Aside from the type of operations performed, each management schedule also specifies the number of times an operation is executed, the type of machine(s) used, the machine and labour time required, and the material/service cost involved. From the information provided in the management schedules, a corresponding set of production cost schedules is developed. These schedules show the depreciation, opportunity, insurance, repair and maintenance, fuel and lubricant, labour and material/service costs associated with each operation. The theory of Capital Budgeting is used here to provide a consistent and accurate estimation of the per hour or annual cost of machinery, equipment and buildings. For each schedule, the sum of the total cost per operation plus the overhead charges, interest on operating capital, and rent and tan on land yield the per acre cost of producing apples. A comparison based on the per acre cost by tree age is performed to determine cost differences that may exist at this level. On average (average of orchard block) per acre cost is determined for British Columbia and Washington State based on the proportion of trees of a specific age and its total cost. This average per acre cost is compared, as well as the individual categories of costs (i.e. labour) to determine where differentials exist between the two regions. Based on an average per acre yield, per pound cost of producing apples is also calculated. The efficiency ratio, total ouput value/total input value, is calculated and compared to provide an insight into British Columbia's producer’s ability to extract profits from inputs. / Land and Food Systems, Faculty of / Graduate

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