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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.
241

The Pika and the Watershed

January 2012 (has links)
abstract: As much as 40% of the world's human population relies on rivers which originate on the Qinghai-Tibetan Plateau (QTP) (Xu et al. 2009, Immerzeel et al. 2010). However, the high alpine grasslands where these rivers emanate are at a crossroads. Fed by seasonal monsoon rains and glacial runoff, these rivers' frequent flooding contributes to massive losses of life and property downstream (Varis et al. 2012). Additionally, upstream grasslands, which regulate the flow of these rivers, are considered to be deteriorating (Harris 2010). This thesis examines the regional vulnerability of these rivers and highlights the impacts of several policy responses, finding that both climate change and grassland degradation pose significant challenges to Asia's water security. Additionally, I suggest that many of the responses elicited by policy makers to meet these challenges have failed. One of these policies has been the poisoning of a small, endemic, burrowing mammal and keystone species, the plateau pika (Ochotona curzoniae) (Smith and Foggin 1999). Contrary to their putative classification as a pest (Fan et al. 1999), I show that the plateau pika is instead an ecosystem engineer that actively increases the infiltration rate of water on the QTP with concomitant benefits to both local ecosystems and downstream hydrological processes. / Dissertation/Thesis / M.S. Biology 2012
242

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.
243

A Solution Under Pressure: Integrating Facilitative Practices into Water-Related Civil Litigations

Koller, David 06 September 2017 (has links)
The broad scope of this research concerns the field of conflict and dispute resolution, also referred to as alternative dispute resolution (ADR). ADR practices have developed in both executive and judicial branches of government since the early 1900’s. The goal of this paper is to evaluate how ADR practitioners working in water-related civil litigation can apply facilitative practices prior, during, and after the proceeding to reduce harm, cost, and time of litigation and increase the overall satisfaction of the parties when the proceeding has been resolved. To achieve this goal, a framework is constructed and applied to a case study in Cascade Locks, Oregon. This framework is not a way to avoid a court proceeding through use of alternative dispute resolution; instead this paper seeks to add facilitative practices to a civil litigation process to make the entire process more efficient to the parties and effective in resolving the dispute.
244

Understanding gully process in two Kansas landscapes

Burke, Katherine J. January 1900 (has links)
Doctor of Philosophy / Department of Environmental Design and Planning Program / Tim Keane / Gullies often form as a result of land use changes and associated factors such as soil compaction, vegetation removal and changes in rainwater infiltration. Gully erosion creates human safety hazards, soil loss, and sediment and nutrient pollution downstream. Across the globe, researchers have found a wide variety of gully growth rates and drivers (Poesen, Nachtergaele, Verstraeten, & Valentin, 2003), but after the late 1900s, very few published gully studies have been done in the United States, and fewer studies have been done in the Midwest and Great Plains regions. This gully study was conducted in two heavily-used Kansas landscapes: Fort Riley military training areas and agricultural fields in McPherson County. The purpose of the study was to quantitatively measure rates and patterns of gully erosion, as well as identify main drivers of gully initiation and growth. Results and conclusions add Kansas gully characteristics to the growing knowledge of gully erosion in other areas of the world. Gullies in both landscapes were surveyed in the field multiple times per year over three consecutive years (2012-2014) to capture patterns and rates of change. Rainfall data and land characteristics such as soils, vegetative cover, slope, and drainage area were compiled into a database to be compared to gully erosion rates in an attempt to correlate gully erosion not only to rainfall but to other land-based factors. Results show that for most Fort Riley gullies, beds are filling and banks are widening, and consistent drivers of erosion could not be determined from the data. In McPherson, gully channels are storing large amounts of sediment, though gully networks in the upper areas of the gully channels are actively widening and advancing headward. Drivers of channel change in McPherson County seem to be related to vegetative cover, slope, and early spring freeze/thaw processes. At both study locations, land use changes related to linear disturbance and reduced vegetative cover are suspected to have more of an influence on gully growth than rainfall events during the study timeframe. Objectives for best management practices are proposed for both Fort Riley and McPherson County.
245

Finding common ground: horse riders' preferences and potential for conflict for varying management actions

Algrim, Susi J. January 1900 (has links)
Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Ryan L. Sharp / The need to balance increasing recreation demands with resource conservation in parks and protected areas presents a challenge for land managers. Managing recreational use of vast land and river areas often encompasses concerns about increasing numbers of recreation visitors, including horse riders. These increases in visitor use may cause adverse impacts to natural resources. A typical outdoor recreation activity, like horse riding, can lead to such impacts as soil erosion, compaction, damage to vegetation, wildlife disturbance, and water pollution. Parks and protected areas require diligent monitoring of these impacts. Along with biophysical impacts, potential social conflicts usually revolve around shared trail use with other horse riders, mountain bikers, and/or hikers. Self-administered questionnaires were given to recreationists (i.e., horse riders) at Ozark National Scenic Riverways (OZAR) in Missouri, U.S.A. Data were collected about levels and patterns of visitor activities on trails at OZAR via stratified random sample at multiple locations, times of day, days of the week and time of year (e.g. summer and fall), thus capturing a representative sample of the riders throughout the whole park. The study examined horse riders’ perceptions of potential management scenarios regarding horse riding trails. Additionally, experience use history data at OZAR were collected. The objective of the research was to explore management options when looking at seasonality, temporal differences, experiential level and the perceived severity of the actions to horse riders at OZAR. The Potential for Conflict Index was used for measuring the potential for conflict between users at different times of the week and times of year (e.g. summer and fall), as well as between horse riders and managers (through proposed management actions). This study sought to help inform park and protected area managers about horse riders’ perceptions of potential management actions and the potential for conflict related to said management actions. Of the management scenarios, there is a lower potential for conflict for trail permitting than trail management. Fall visitors had a higher potential for conflict regarding trail permitting (PCI₂ value = 0.43) and fall users also had a higher potential for conflict for trail management (PCI₂ value = 0.25). For expert and novice users, both groups felt similarly about trail conditions, trail permitting, and trail management; however, there was an overall lower potential for conflict for expert horse riders than novice horse riders. The results revealed the complexity of managing horse use in a protected area. Even during periods of high use, horse riders did not report crowded conditions, nor did horse riders favor restricting use on the trails. Additionally, horse riders felt that the trail conditions were acceptable. As past research has shown, increased horse use often leads to degraded ecological conditions (though none was perceived) and possible conflicts with other users (but not intra-activity). Limiting use may be the only viable way to maintain the ecological integrity of the park, regardless of horse riders lack of desire for restricted use or the presence of experiential impacts. Managers often have to make difficult decisions in the face of conflicting information, and this study clearly displays this dilemma.
246

Measuring the Sustainability of Protected Area-Based Tourism Systems: A Multimethod Approach

January 2014 (has links)
abstract: This research assessed the sustainability of protected area-based tourism systems in Nepal. The research was composed of three interrelated studies. The first study evaluated different approaches to protected area governance. This was a multiple-case study research involving three protected areas in Nepal: the Annapurna Conservation Area, Chitwan National Park, and the Kanchenjunga Conservation Area. Data were collected from various published and unpublished sources and supplemented with 55 face-to-face interviews. Results revealed that outcomes pertaining to biodiversity conservation, community livelihoods, and sustainable tourism vary across these protected areas. The study concluded that there is no institutional panacea for managing protected areas. The second study diagnosed the sustainability of tourism in two destination communities: Ghandruk and Sauraha, which are located within the Annapurna Conservation Area and Chitwan National Park, respectively. A systemic, holistic approach--the social-ecological system framework--was used to analyze the structures, processes, and outcomes of tourism development. Data collection involved 45 face-to-face semi-structured interviews and a review of published and unpublished documents. Results revealed that tourism has several positive and a few negative sociocultural, economic, and ecological outcomes in both communities. Overall, tourism has progressed towards sustainability in these destinations. The third study examined tourism stakeholders' perspectives regarding sustainable tourism outcomes in protected areas. The study compared the responses of residents with residents, as well as tourists with tourists, across the Annapurna Conservation Area and Chitwan National Park. Tourism sustainability was evaluated with six tourism impact subscales measuring negative and positive ecological, economic, and social impacts. Data were collected using the survey method. Respondents included 230 residents and 205 tourists in Annapurna, and 220 residents and 210 tourists in Chitwan. The findings revealed that the residents across these protected areas perceived positive and negative impacts differently, as did the tourists, suggesting that the form of tourism development affects the sustainability outcomes in protected areas. Overall, this research concluded that protected areas and tourism are intricately related, and sustainable management of a protected area-based tourism system requires a polycentric adaptive approach that warrants a broad participation of relevant stakeholders. / Dissertation/Thesis / Doctoral Dissertation Community Resources and Development 2014
247

Flame Retardant Chemical Contamination of Seafood, Ecologically Sustainable Fisheries, and Significance for Biodiversity Conservation

January 2015 (has links)
abstract: Consumption of seafood poses a substantial threat to global biodiversity. Chemical contamination found in both wild-caught and farmed seafood also presents significant health risks to consumers. Flame retardants, used in textiles, upholstery, plastics, and other products to reduce risk of fire-related injury, are of particular concern as they are commonly found in the marine environment and permeate the tissues of fish that are sold for consumption via multiple pathways. The widespread issue of fishery collapse could be alleviated by demonstrating to stakeholders that many unsustainable fish stocks are also unhealthy and mutually disadvantageous for both human consumers and the environment. To thoroughly investigate the confounding factors and contradictory signals enmeshed in the relationship between ecologically sustainable fisheries and flame retardant contamination, I examined the biological characteristics of regional fish stocks which drive both contamination and perceived sustainability. I found that the biological and spatial aspects of commonly consumed aquatic and marine species best predict contamination when compared with various indices of sustainability. My results confirm that knowledge of flame retardant toxicity will become increasingly more important to consumers because a high percentage of global populations rely on coastal seafood for subsistence, and although dispersal of chemical contamination is still a poorly understood phenomenon, fish harvested closer to land are likely to contain higher concentrations of potentially harmful chemicals. Because some of the same biological traits which facilitate the uptake of chemicals also contribute to how a species responds to fishing pressures, concern for private health increases public consideration for the conservation of species at risk. / Dissertation/Thesis / Masters Thesis Biology 2015
248

Vegetation Community Responses to Juniper Slash/Burn and Broadcast Burn on A Semi-Desert Tobosa Grassland

January 2015 (has links)
abstract: ABSTRACT Modern management techniques to maintain rangelands and deter encroachment of juniper into grassland habitats currently includes fire prescription. Additionally, a large body of research has indicated that fire has multiple benefits to grasslands resulting in increased diversity of flora and fauna. In the semi-arid grassland of the Agua Fria National Monument, fire treatments may be able to provide similar advantages. This study considers two methods of fire prescription on the Agua Fria National Monument within central Arizona: 1) Juniper thinning with pile burning; 2) Broadcast burning. The Agua Fria National Monument upland ecosystem has limited research focusing on semi-arid grassland and juniper stand’s response to implemented treatments over time. The four year monitoring duration of this study aids in assessing the outcome of treatments and reaching the objectives of the management plan. Vegetation in 981 quadrats was measured for species richness, cover, densities, height, and biomass during the fire prescription period from 2009 through 2013. The study was divided into two treatment types: 1) Juniper cutting and pile burn; 2) Broadcast burn areas in open grasslands. Results of this study provide consistent examples of vegetative change and community movement towards positive response. Percent composition of overall vegetation is 5 – 30% with >50% of litter, bare ground and rock cover. Juniper sites have immediate consequences from tree thinning activities that may be beneficial to wildlife, particularly as connective corridors pronghorn antelope. Grass height was significantly reduced as well as forb density. Forbs that are highly responsive to environmental factors indicate an increase after the second year. Analysis results from grasslands indicated that cactus and unpalatable shrubs are reduced by fire but a return to pre-burn conditions occur by the third year after fire disturbance. Percent cover of perennial grasses has shown a slow increase. Wright’s buckwheat, a palatable shrub, has increased in density and height, indicating fire adaptations in the species. Species richness was reduced in the first year but increase in density continues into the third year after burn. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2015
249

Exploring Resident’s Xeriscaping Preference: The Influence of Ecological World View and Place Identity

January 2018 (has links)
abstract: For the last 10 years, the American Southwest has been experiencing the most persistent drought conditions on record. Based on future climactic predictions, there is a dire need to reduce water usage within Phoenix. An environmentally responsible behavior such as low water use landscaping (xeriscaping), has been shown to reduce household water consumption by 40%-70%. While much is known regarding the relationship between socio-demographics and xeriscaping choices, the influence of other variables remains to be explored. Using data from the 2017 Phoenix Area Social Survey, this study investigates the influence of two additional variables - ecological worldview and place identity on xeriscaping choice. Data was analyzed using two models - Ordinary Least Squares (OLS) and Linear Probability Model (LPM). Ecological worldview and place identity, along with income, ethnicity, and gender, were all found to be positively related to xeriscape preference. Additionally, when compared to the LPM, the traditional OLS was found to still be the most robust and appropriate model when measuring landscape preference. Finally, results suggested that programs to foster identity with the local desert mountain parks may help to increase xeriscaping in the Valley and thus lower residential water use. / Dissertation/Thesis / Masters Thesis Community Resources and Development 2018
250

Modeling Suitable Habitat Under Climate Change for Chaparral Shrub Communities in the Santa Monica Mountains National Recreation Area, California

January 2014 (has links)
abstract: Species distribution modeling is used to study changes in biodiversity and species range shifts, two currently well-known manifestations of climate change. The focus of this study is to explore how distributions of suitable habitat might shift under climate change for shrub communities within the Santa Monica Mountains National Recreation Area (SMMNRA), through a comparison of community level to individual species level distribution modeling. Species level modeling is more commonly utilized, in part because community level modeling requires detailed community composition data that are not always available. However, community level modeling may better detect patterns in biodiversity. To examine the projected impact on suitable habitat in the study area, I used the MaxEnt modeling algorithm to create and evaluate species distribution models with presence only data for two future climate models at community and individual species levels. I contrasted the outcomes as a method to describe uncertainty in projected models. To derive a range of sensitivity outcomes I extracted probability frequency distributions for suitable habitat from raster grids for communities modeled directly as species groups and contrasted those with communities assembled from intersected individual species models. The intersected species models were more sensitive to climate change relative to the grouped community models. Suitable habitat in SMMNRA's bounds was projected to decline from about 30-90% for the intersected models and about 20-80% for the grouped models from its current state. Models generally captured floristic distinction between community types as drought tolerance. Overall the impact on drought tolerant communities, growing in hotter, drier habitat such as Coastal Sage Scrub, was predicted to be less than on communities growing in cooler, moister more interior habitat, such as some chaparral types. Of the two future climate change models, the wetter model projected less impact for most communities. These results help define risk exposure for communities and species in this conservation area and could be used by managers to focus vegetation monitoring tasks to detect early response to climate change. Increasingly hot and dry conditions could motivate opportunistic restoration projects for Coastal Sage Scrub, a threatened vegetation type in Southern California. / Dissertation/Thesis / M.A. Geography 2014

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