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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.
31

WATERSHED RESTORATION EFFORTS AT HART PRAIRIE IN NORTHERN ARIZONA

Kursky, Joshua, Tecle, Aregai 18 April 2015 (has links)
Hart Prairie is a high-elevation upland riparian ecosystem on the west slope of the San Francisco Peaks in northern Arizona. The location is unique, not only as an upland riparian area in the semi-arid Southwest, but also for having a wet meadow ecosystem dominated by Bebb willow (Salix bebbiana). The ecosystem has experienced a high degree of change since the time of Euro-American settlement. Along with fire suppression, increased wild ungulate herbivory rates, and conifer encroachment into a historically short-grass prairie, several humaninduced changes have been made to the topography of the watershed. Stock tanks, an earthen berm with associated diversion channels, and a road that cuts perpendicularly across the direction of water flow near the base of the watershed have contributed to the altered drainage patterns and the decreased water availability to the flora and fauna in the area. As a result, the Bebb willows and the associated meadow vegetation are at risk. Most of the willows, which constitute the majority of the canopy in the ecosystem, are at a decadent, over-mature stage that allows a limited recruitment of younger plants (Maschinski 1991, Waring 1992). Under these conditions, the plant community may die off leading to the loss of this rare riparian area forever. Research on restoration efforts have been undertaken since the mid-1990s on The Nature Conservancy’s Hart Prairie Preserve and the adjacent US Forest Service Fern Mountain Botanical Area. This paper summarizes the efforts that have been made; most of which targeted to improve the low germination rates of willow seeds, and to restore the geomorphology and surface flow patterns to their pre-disturbance conditions.
32

RESTORING THE WATER QUALITY OF THE SAN PEDRO RIVER WATERSHED

Klotz, Jason, Tecle, Aregai 18 April 2015 (has links)
This paper is concerned with restoring the quality of water in some portions of the San Pedro River. There are high concentrations of bacteria in some parts of the San Pedro River. Our aim is to find ways of improving the situation. Specifically, there are two objectives in the study. The first one attempts to identify the possible sources of the bacterial contamination and assess its trends within the watershed. The second objective is to determine appropriate methods of restoring the water quality. The main water quality problem is nonpoint source pollution, which enters the stream and moves along with it. The magnitude of the problem is affected by the size and duration of the streamflow, which brings bacteria-laden sediment. The amount of sediment brought into the system is large during the monsoonal events. At this time, the streamflow becomes highly turbid in response to the organic and inorganic sediments entering the system. Based on research done for this paper, the amount of bacterial concentration is strongly related to turbidity. Best management practices (BMPs) have been designed and implemented to restore the water quality problem in the area. The BMP's consist of actions such as monitoring, educational outreach, proper signage, and other range/watershed related improvement practices. Other issues that contribute to the increasing amount of bacteria that are briefly addressed in this paper are bank and gully erosion, flood control, and surface water and streamflow issues that occur on the stream headwaters.
33

RESTORATION OF THE LAS VEGAS WASH AND ASSOCIATED WETLANDS IN LAS VEGAS, NEVADA

Burke, Megan 18 April 2015 (has links)
This paper evaluates the historical growth of the Las Vegas Wash, its subsequent degradation, and the current efforts to restore and stabilize its channel. The Las Vegas Valley Metropolitan Area is located in the Mohave Desert in a drainage basin surrounded by mountain ranges. This drainage basin and its dynamic system of stream channels constitute the Las Vegas Watershed in which the Wash is located. The condition of the Las Vegas Wash is unique, as is a perennial stream that evolved from an ephemeral wash in response to the rapid urbanization and subsequent production of treated wastewater input into the stream channel. The situation has created a series of wetland ecosystems along the Wash, and valuable riparian habitat in such an arid environment. The Wash and its associated wetlands system provide a variety of ecological services to the city of Las Vegas, including storm water conveyance, wastewater effluent filtration, flood protection, and a green space for residents to enjoy. However, continuous increase in volume and intensity of the stream flow has resulted in severe channel degradation and bank erosion in numerous locations along the stream channel. After an examination of the historic and present-day conditions of the Wash and its restoration activities, this essay suggests that future evaluations of the Las Vegas Wash case study may provide evidence to support the propagation of collaborative management efforts.
34

DETERMINING SUCCESS IN WATERSHED RESTORATION USING INTERDISCIPLINARY METRICS: RIO SALADO ENVIRONMENTAL RESTORATION PROJECT, PHOENIX, ARIZONA

Schmidt, Carly H. 18 April 2015 (has links)
Ecological restoration has yet to gain an indepth understanding of the social dynamics that inform restoration design and enable improved watershed performance in urban environments. The Rio Salado Environmental Restoration Project is unique in that the scale of the project expands to new reaches of the Salt River with each successful venture. The 40-year project has been most successful in recent years due to innovative strategies that capitalize on public outreach and inclusion. Adoption of multi-purpose objectives that include partnerships, public stakeholders, and learning achievement have contributed to the project's success. The ability of the restored system to withstand flood events is one of the many examples demonstrating the project's qualifications as a model for future urban restoration efforts. Lessons about the social dynamics that inform urban restoration success have the potential to augment scientific learning in ecological restoration.
35

Hydrology and Water Resources in Arizona and the Southwest, Volume 44 (2015)

18 April 2015 (has links)
No description available.
36

A Study to Determine the Soundness of Graduate Educational-administrative Courses Offered in Twenty-seven Southwestern Colleges and Universities

Thomas, R. Edward 06 1900 (has links)
The purpose of this study is to determine the soundness of the graduate educational-administration programs in the leading colleges and universities of Texas, Oklahoma, Arkansas, Colorado, and New Mexico, in the light of criteria derived from psychologies of learning, and the etiologies of desirable traits such as leadership. A second purpose for setting up such criteria is to have a basis from which to draw recommendations and suggestions for improvement.
37

An Evaluation of Public Relations as Practiced by Southwestern Bell Telephone Company

Gallagher, Eddye S. 08 1900 (has links)
This study presents a detailed analysis of the public relations organization, objectives, and practices of Southwestern Bell Telephone Company, Dallas, Texas. Information sources included interviews with telephone company public relations personnel, company publications, and other publications. The five chapters deal with the history and development of the company and its public relations program, and the organization, functions, and operations of the public relations department. With a long and varied history of public relations activities, the company executes numerous activities for employees, customers, educational institutions, the community, stockholders, and the media. The study recommends that the department establish a committee to formulate long-range public relations goals, initiate a management orientation program, and advertise in area high school and college publications.
38

Effect of the ecdysone agonists, methoxyfenozide and tebufenozide, on European and Southwestern corn borers in vivo and in vitro

Trisyono, Y. Andi, January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 130-148). Also available on the Internet.
39

Hydrology and Water Resources in Arizona and the Southwest, Volume 1 (1971)

23 April 1971 (has links)
Complete issue of the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona
40

Hydrology and Water Resources in Arizona and the Southwest, Volume 2 (1972)

06 May 1972 (has links)
Complete issue of the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona

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