• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 19
  • 16
  • Tagged with
  • 48
  • 25
  • 19
  • 16
  • 15
  • 9
  • 9
  • 8
  • 8
  • 7
  • 7
  • 7
  • 7
  • 7
  • 6
  • 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.
31

Influences on Stakeholder Participation in Water Negotiations: A Case Study from the Klamath Basin

Horangic, Alexandra, Berry, Kate A., Wall, Tamara 15 March 2016 (has links)
In water governance, where problems are controversial and value laden, different forms of stakeholder involvement have become common and are frequently required. Stakeholder participation is often recognized as fundamental to the legitimacy and success of negotiated environmental decisions, but the intricacies of why stakeholders participate has received less attention. We examine factors that influenced stakeholder participation in the Klamath Basin Restoration Agreement and Klamath Hydroelectric Settlement Agreement of 2010. The research draws on in-depth, semistructured interviews of a sample recruited from stakeholder organizations in the Klamath River Basin. Results indicate that previous negative experiences did not translate into nonparticipation; divisions within seemingly aligned stakeholder organizations encouraged some stakeholders to participate and others to actively oppose negotiations; stakeholders' perceptions of power differentials encouraged both stakeholder participation and exclusion in negotiations; and concerns about relationship development during negotiations suggest that relationship building may be viewed as part of the negotiation process.
32

The structure, geologic evolution and regional significance of the Bethel Creek-North Fork area, Coos and Curry counties, Oregon

Gullixson, Carl Fredrick 01 January 1981 (has links)
The original purpose of this study was a detailed structural analysis of the Jurassic Otter Point Formation in order to determine if the Canyonville Fault Zone, which forms the northern boundary of the Klamath Mountains in the Riddle - Canyonville area (Benson and Perttu, 1980), extends westward to the coast and, if possible, to characterize the structure of the Otter Point Formation. Further, a detailed examination of the structural and stratigraphic relationships between the Otter Point Formation and the Eocene Roseburg and Lookingglass Formations was to be performed in an attempt to determine the tectonic history of the area.
33

Using Wetlands to Prevent the Surface Accumulation of <i>Aphanizomenon flos-aquae</i> from Upper Klamath Lake

Rouhe, Arick Christopher 02 August 2018 (has links)
The ability to regulate buoyancy (sinking and floating) using cellular gas vesicles is a unique characteristic that allows many common bloom-forming cyanobacteria to accumulate at water surfaces and dominate systems. Typical control and management strategies include nutrient manipulation and phosphorus reduction, which are effective but do not reduce the advantage of buoyancy control. Since buoyancy control is based upon a mechanism that is driven by photosynthesis along with environmental conditions that trigger vesicle formation and ion exchange, buoyancy regulation can be influenced by manipulating extracellular conditions. In this study I manipulated extracellular conditions using wetland water and additions of potassium, sodium, and calcium in small-scale lab experiments and larger scale, near-lake containers with Aphanizomenon flos-aquae from Upper Klamath Lake, Oregon. The results indicate a target mixture of 10% wetland water reduces surface accumulation, increases cellular turgor pressure (a measure of the ability of gas vesicle forming cells to control buoyancy), and leads to fewer rafts at the surface of the water column. By adding ions at the same concentration as the target wetland mixture, similar results were found. This research represents the basis of a possible strategy for mitigating surface blooms of buoyant cyanobacteria in lakes using wetland water and/or ion additions that could be used in tandem with nutrient manipulation and phosphorus reduction.
34

Breeding and foraging ecology of Caspian terns nesting on artificial islands in the Upper Klamath Basin, California

Patterson, Allison (Allison Glider) 13 November 2012 (has links)
Availability of suitable nesting habitat that is free of nest predators and provides access to adequate prey resources within commuting distance is a major factor limiting seabird populations. Caspian terns (Hydroprogne caspia) in western North America have shifted their breeding habitat from naturally occurring habitats in interior wetlands, lakes, and rivers to primarily human-created habitats in coastal bays and estuaries. This shift has brought Caspian terns into conflict with fisheries of conservation concern, in particular anadromous salmonids. Prior to the 2010 breeding season, three artificial islands were built in the Klamath Basin National Wildlife Refuge (NWR) Complex as alternative nesting habitat for Caspian terns currently nesting at the world's largest colony for the species, near the mouth of the Columbia River, Oregon. I investigated the efficacy of habitat creation (island building) and social attraction (decoys and recorded vocalizations) for establishing new breeding colonies in the Upper Klamath Basin, California. In 2010, approximately 258 pairs of Caspian terns attempted to nest on the new islands and raised an average of 0.65 fledglings/breeding pair; in 2011, 222 pairs attempted to nest and raised an average of 0.11 fledglings/breeding pair. Competition with California and ring-billed gulls (Larus californicus and L. delawarensis) for nesting space, gull predation on Caspian tern eggs and chicks, low water levels, and depredation by great horned owls (Bubo virginianus) were the primary factors limiting colony development and productivity, especially in 2011. The immediate response by Caspian terns to habitat creation and social attraction in the Upper Klamath Basin demonstrates that these can be effective restoration techniques to establish new breeding colonies where nesting habitat is a major limiting factor; however, continued management of other limiting factors (e.g., control of on-colony predators and competitors) will likely be necessary to promote the development of established, self-sustaining breeding colonies on these artificial islands. Efforts to conserve and restore seabird colonies can be compromised by low prey availability within foraging distance of the breeding colony. I used GPS telemetry to study the fine-scale foraging behavior of Caspian terns nesting at two newly established colonies and cluster analysis to discriminate behavioral states based on movement characteristics. Terns breeding at the Sheepy Lake colony spent less time at the colony (52% of the day) than terns breeding at the Tule Lake colony (74%). Caspian terns breeding at Sheepy Lake foraged more extensively than terns breeding at Tule Lake; the foraging trips of Sheepy Lake terns lasted longer (median = 186 min) and were longer-distance (27 km) compared to those of Tule Lake terns (55 min and 6 km, respectively). Between-colony differences in foraging behavior corresponded to 5% lower average body mass of breeding adults and significantly lower size-adjusted body mass of chicks at the Sheepy Lake colony compared to the Tule Lake colony. Proximity to high-quality foraging areas influenced the foraging behavior and parental care of breeding Caspian terns, which in turn had effects on nesting success. The successful use of GPS telemetry to study the fine-scale foraging behavior of Caspian terns represents a significant advance in our ability to investigate the foraging ecology of this species and other moderate-sized seabirds. / Graduation date: 2013
35

Bioassessment of irrigation drainwater effects on aquatic resources in the Klamath Basin of California and Oregon /

Bennett, Jewel Kay. January 1994 (has links)
Thesis (Ph. D.)--University of Washington, 1994. / Vita. Includes bibliographical references (leaves [134]-156).
36

The Tlegetlinten Site (35CU59) and its place in southwest Oregon prehistory /

Tisdale, Lucille. January 1986 (has links)
Thesis (M.A.)--Oregon State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 113-128). Also available online.
37

Transforming Regulatory Processes: Karuk Participation in the Klamath River Total Maximum Daily Load (TMDL) Process

Stoll, Shannan 21 November 2016 (has links)
This thesis examines the extent to which the Karuk Tribe has participated in natural resource management regulatory processes, using the Klamath River Total Maximum Daily Load (TMDL) process as a particular case study for evaluation. One of the most effective ways that the Tribe participates in the TMDL process is through the rigorous adoption of the technical tools of regulatory science. Collaboration with nontribal organizations is also used to build capacity for participation. The Tribe’s active participation in the TMDL process has in turn shaped the process, making it more inclusive of tribal values and traditional knowledge, improving overall scientific inquiry, and facilitating increased cooperation among tribal and non-tribal resource managers. At the same time, the Tribe’s participation in the process remains “uneven,” underscoring the ongoing challenge of making regulatory processes that recognize the legitimacy of tribal knowledge and values.
38

Drought Analysis under Climate Change by Application of Drought Indices and Copulas

Yang, Wen 01 January 2010 (has links)
Drought is a recurrent extreme climate event with tremendous hazard for every specter of natural environment and human lives. Drought analysis usually involves characterizing drought severity, duration and intensity. Similar to most of the hydrological problems, such characteristic variables are usually not independent. Copula, as a model of multivariate distribution, widely used in finance, actuarial analysis, has won increasingly popularity in hydrological study. Here, the study has two major focuses: (1) fit drought characteristics from Streamflow Drought Index (SDI) or Standardized Runoff Index (SRI) to appropriate copulas, then using fitted copulas to estimate conditional drought severity distribution and joint return periods for both historical time period 1920-2009 and future time period 2020-2090. SDI is calculated based on long term observed streamflow while SRI is based on simulated future runoff. Parameters estimation of marginal distribution and copulas are provided, with goodness fit measures as well; (2) investigate the effects of climate change on the frequency and severity of droughts. In order to quantify the impact, three drought indices have been proposed for this study to characterize the drought duration, severity and intensity changes under the climate change in Upper Klamath River Basin. Since drought can be defined as different types, such as meteorological drought, agricultural drought, hydrological drought and social economical drought, this study chooses Standardized Precipitation Index (SPI), Palmer Drought Severity Index (PDSI) and Surface Water Supply Index (SWSI) to estimate the meteorological, agricultural and hydrological drought, respectively. Climate change effects come from three sources: the inherent reason, the human activity and the GCMs uncertainties. Therefore, the results show the long term drought condition by calculating yearly drought indices, and compared in three ways: First, compare drought characteristics of future time periods with base period; second, show the uncertainties of three greenhouse gas emission scenarios; third, present the uncertainties of six General Circulation Models (GCMs).
39

Effects of Wildland Urban Interface Fuel Treatments on Fire Behavior and Ecosystem Services in the Klamath Mountains of California

Large, Jonathan A 01 August 2010 (has links) (PDF)
Greater numbers of people are moving into wildland-urban interface (WUI) areas, increasing the number of people at risk to large wildfires. To mitigate the hazard, emphasis is often placed on fuel treatments used to reduce fuel loads and subsequent fire behavior. This approach overlooks the additional benefits provided by vegetation, including carbon storage and sequestration along with air pollutant removal. This study aimed to calculate and compare differences in representative values by examining a study site in the Klamath Mountains of Northern California. Fire behavior simulations were done under various weather scenarios to illustrate both the impact of weather on fire intensity as well as the limitations of various fuel treatments. Ecosystem services were modeled using the I-tree Eco software (formerly the Urban Forest Effects model). Results showed a reduction in surface and an increase in canopy base height from the treatments and subsequent reductions in fire intensity under moderate and high conditions with the largest difference occurring in the Thin + Fire treatment. Under extreme weather conditions, the effectiveness of all fuel treatments was reduced. Ecosystem services showed a reduction of carbon sequestration in the fuel treatments corresponding to the reduction of smaller diameter trees from the fuel treatments. The greatest difference occurred in the Thin + Fire treatment. These results and the methods used to acquire them show the impacts from fuel treatments can be characterized and compared. This information will allow land managers to make decisions that account for a variety of considerations, while also providing them with tools that can facilitate the cooperation and collaboration of multiple stakeholders.
40

Influence of Mixing and Buoyancy on Competition Between Cyanobacteria Species in Upper Klamath Lake

Brunkalla, Roberta Joann 22 May 2017 (has links)
Cyanobacterial blooms in lakes impact human health, the economy, and ecosystem health. It is predicted that climate change will promote and increase the frequency and intensity of cyanobacterial blooms due to unique physiological adaptions that allow cyanobacteria to exploit warm stable water bodies. Key cyanobacteria physiological adaptions include nitrogen fixation, buoyancy regulation and higher optimum growth temperatures. The largest uncertainty of predicting the effect of climate change is in understanding how the interactions among species will change. Adding to the ambiguity, cyanobacteria physiological adaptions can vary based on lakespecific ecotypes and can have different sensitivities to temperature. It is critical to understand how cyanobacterial physiological adaptions impact species interactions in order to improve and devise adaptable, short‐term management methods for bloom control. This study investigated how weather patterns and algal buoyancy regulation influence the competition and accumulation of two bloom‐forming buoyant cyanobacteria species (Aphanizomenon flos‐aquae (APFA) and toxin‐forming Microcystis aeruginosa (MSAE)) in Upper Klamath Lake (UKL), Oregon. The focus was confirming the buoyancy rate of the APFA in Upper Klamath Lake and exploring whether short‐term weather conditions could lead to dangerous accumulations of APFA or MSAE. A sensitivity analysis was conducted on the model's buoyancy terms and growth curves to see if the outcome of competition was influenced by these parameters. UKL specific buoyancy rates were measured on APFA from samples taken directly from the lake in the summer of 2015. Tracking software was used to measure APFA movement through water, and individual colony movement was averaged to obtain a single buoyancy rate. There was a high degree of agreement between the calculated APFA buoyancy rate in UKL (0.89 ± 0.34 m hr-1) with the rate published by Walsby (1995; 0.9 ± 0.5 m hr-1). This study investigated how weather patterns and buoyancy regulation influenced the outcome of competition between APFA and MSAE. Weather and water column temperature data were collected from UKL in the summer of 2016. A onedimensional hydrodynamic model was used to calculate the lake's thermal and turbulence structure on days with contrasting weather patterns (hot/cool and windy/calm). A competition model was used to calculate the accumulation of APFA and MSAE cells in regular intervals through the water column under the various weather scenarios. MSAE accumulation was significantly influenced by the thermal and turbulence regimes, but APFA maintained high accumulations under every regime and was the better competitor under every thermal and turbulence regime. MSAE was more negatively impacted by high turbulence than low temperatures. APFA's optimum temperature growth curve was found to be important in determining the outcome of competition between APFA and MSAE. Surprisingly, competition was not sensitive to changes in buoyancy rates. Buoyancy was not found to be a function of algal accumulation under any thermal and turbulence regime. The impacts of climate change and human‐induced enrichment has the potential to change existing patterns of species interactions in lentic systems. Restoration and management efforts should consider the significance of cascading ecological responses to climate change. Understanding how key physiological adaptions operate is the first step to assessing the scope of this impact. While buoyancy might not play a large role in competition in UKL, it might be possible to use mixing to suppress MSAE because it is negatively impacted by high turbulence. If MSAE hot spots become a reoccurring problem in UKL, lakes managers might be able to use localized mixing to suppress MSAE blooms in these problem areas.

Page generated in 0.0291 seconds