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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.
571

An Analysis of the Rhetoric of Agitation and Control in the Sierra Club Campaign to Protect the Grand Canyon

Wilson, Joy 12 1900 (has links)
This study of the rhetoric in the Sierra Club's Grand Canyon Campaign, 1963 to 1967 seeks to determine the decisive strategies in the success of the campaign. Criteria for examining the rhetoric are adapted from the fields of rhetoric and sociology. This analysis examines preconditions of this conservation campaign, its leaders, membership, strategies, and audience-speaker relationships, The campaign's turning point came when the club used public audiences to pressure Control into capitulating to Agitation's demands, Other factors in the campaign's success were the Sierra Club's purity of belief, suppression action by Control, and incomplete purity of belief in the leader of Control.
572

The cretaceous stratigraphy and mineral deposits of the east face of Black Mesa, Apache County, Arizona

Merrin, Seymour, 1931- January 1954 (has links)
No description available.
573

Cattle grazing behavior and range plant dynamics in southern Arizona.

Gamougoun, Ngartoina Dedjir. January 1987 (has links)
A 15-month study was conducted on the Santa Rita Experimental Range to evaluate the factors influencing both plants and cattle in southern Arizona. Forage biomass, nutrient value, botanical composition, and ground cover were greater in the growing season than in the dormant season. Moderate and heavy pastures had lower plant parameters than very heavy pasture, except for forage biomass and Lehmann lovegrass proportion, forage fiber and ground cover. Slopes and washes had a higher forage nutrient content and lower biomass and ground cover than the uplands. Lehmann lovegrass was more abundant on the uplands and in the washes than on the slopes and the reverse was true for native grasses and shrubs. Understory forages contained greater nutrients and forbs than open forages and the opposite occurred for shrubs and ground cover. Grazing activities, drinking, salting, defecation, urination and rumination were greater in the growing seasons, but standing and idling were greater in winter. There were no differences among pastures in major activities, but walking, drinking and salting were greater on very heavy pasture than on moderate and heavy pastures. Most grazing activities were on the uplands and resting activities were in the washes. Biting rates were similar among topographic areas. Upland and wash defecation and urination frequencies were similar and higher than slope frequencies. Grazing activities were greater in the open than under canopy and the reverse was true for resting activities. Open and canopy areas were similar in defecation and urination frequencies and biting rates. Except for resting activities, major and minor activities were more intense in the afternoon than in the morning. Morning and afternoon biting rates were similar. The weather index was the most important predictor of all cattle activities, except for the defecation frequency which mostly depended on the proportion of green forage. The forage nutrients and green proportion were the second and third important predictors of cattle activities, respectively. In conclusion, plants and animals interact and both react to environmental conditions. The recommendations for best management of a grazing land ecosystem should consider these conditions.
574

PREHISTORIC AGRICULTURAL ADAPTATION AND SETTLEMENT IN LONG HOUSE VALLEY, NORTHEASTERN ARIZONA.

HARRILL, BRUCE GILBERT. January 1982 (has links)
A recently completed intensive archaeological survey of Long House Valley in northeastern Arizona has provided a detailed body of data on prehistoric settlement distribution and environmental variation. Long House Valley was occupied between A.D. 1 and 1300 by prehistoric agriculturalists referred to as the Kayenta Anasazi. This study examines the changing relationship between settlement locations and agricultural adaptations from A.D. 500 to 1300 in Long House Valley. As part of this analysis, the archaeological, ethnographic, and environmental background of the Kayenta region is reviewed as a basis for understanding the nature of agricultural adaptation in this region. Agricultural practices of the Hopi Indians of northern Arizona provide the basis for a model of probable agricultural field locations. This combined with an examination of the physiographic, hydrographic, and edaphic features in the valley allow identification of potential field areas. Changes in the potential of identified field areas are postulated on the basis of variation in available moisture as determined from a regional dendroclimatic reconstruction. Prehistoric habitation site locations and their changing distribution through time are examined against these proposed changes in field potential. This study demonstrates that there is a distinct positive correlation between settlement location and potential field location as determined by available moisture. Beginning about A.D. 1150 deteriorating environmental conditions in the form of decreased moisture, arroyo cutting, and lowered water table are considered the primary determinants of changes in site locations. These changes are viewed as an adaptive response by the Kayenta Anasazi to conditions of decreased moisture. Continuing deterioration of the environment made the practice of agriculture impossible and resulted in the total abandonment of Long House Valley and the entire Kayenta region by A.D. 1300.
575

The Geology and Mineralization of the Sedimentary Hills Area, Pima County, Arizona

Bennett, Paul J. January 1957 (has links)
Mildly metamorphosed Cretaceous siltstones, arkoses and limey shales and a small composite stock of granitic composition are the principal rocks exposed in the Sedimentary Hills area, which lies six miles west of Tucson, Arizona. About 2400 feet of sediments were measured and assigned to the Amole Arkose Formation. The beds dip to the south and strike northwesterly. The stock is composed of two granitic facies. The northern and earlier part of the stock is a quartz monzonite which is mildly altered. The southern part of the intrusive is a granite porphyry which is altered to a greater degree and exhibits significant disseminations of chalcopyrite and pyrite. A quartz-pegmatite plug, probably a late phase of the intrusions, intrudes the quartz monzonite. Structure in the area is dominated by a large thrust zone which strikes generally parallel to the bedding. Within the Sedimentary Hills area, normal faulting and drag folding are tributary to the thrusting. Minor copper oxide minerals are frequent along large and small faults, and in the granite porphyry stock. Wide brick-red and brown gossans occur along the major thrust plane.
576

SELECTED ASPECTS OF POWER ENGINEERING AS RELATED TO THE WESTERN AREA POWER ADMINISTRATION.

Sundberg, John Raynor. January 1982 (has links)
No description available.
577

Effects of the Recreational Fee Demonstration Program on backcountry users in Grand Canyon and Everglades National Parks /

Leahy, Jessica E. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 88-91). Also available on the World Wide Web.
578

Agriculture and society in arid lands: a Hohokam case study

Fish, Suzanne K. January 1993 (has links)
The interplay between social and productive spheres in arid land agrarian societies with non-mechanized technologies is exemplified in a case study of the prehistoric Hohokam Indians of southern Arizona. In addition to chapters unique to the dissertation, ten papers are included that were published during the period of doctoral enrollment. Results from a variety of investigative techniques are combined to characterize Hohokam agriculture and its relationship to societal forms and dynamics. Among these are archaeological survey and settlement pattern analysis, technical studies of prehistoric fields, palynological analysis for reconstruction of agricultural environments, and comparison with methods and concepts employed by historic and modern traditional farmers in the southwestern United States and northwestern Mexico. Hohokam farming is examined at sequential scales, beginning with the setting, layout, and yield of individual fields and ending with comparison between Hohokam agricultural configurations and those of other arid land cultures. Topics receiving emphasis within the broader dissertation theme are the nature of Hohokam agrarian landscapes, the recently recognized role of cultivated agave in subsistence systems, and the social and economic framework for agricultural decision-making and strategies.
579

Recharge characteristics of an effluent dominated stream near Tucson, Arizona

Lacher, Laurel Jane,1964- January 1996 (has links)
Almost 90% of the treated sewage effluent processed by the two treatment plants serving the greater Tucson area is available for passive recharge through the Santa Cruz River streambed north of Tucson. In the absence of any major disturbance of the effluent channel, the recharge capacity of the streambed materials decreases over time as microbial activity, and possibly suspended sediments settling out of solution, act to clog the surficial sediments under the effluent stream. Effluent stream transmission-loss measurements made over the period from November 1994 to August 1995 provided data used to determine the average vertical hydraulic conductivity of the low-flow channel in the study reach through simulations using the computer model known as KINEROS2. Saturated hydraulic conductivity (KSAT) served as the calibration parameter in the model. The appropriate KSAT value was chosen for each set of field data by matching the observed and simulated downstream hydrographs for the study reach. KSAT values were corrected for viscosity changes resulting from changing average daily surface water temperatures over the study period. Saturated hydraulic conductivity values for the effluent stream channel ranged from a maximum of 37 mm/hr in January, 1995, following several major winter storms, to a minimum of 11 mm/hr in August, 1995, after a nearly six-month interstorm period. The saturated hydraulic conductivity values decay exponentially with time after the last major winter storm. The mathematical model describing this decay may be used to estimate effluent recharge rates under similar future meteorological and climatological conditions.
580

CHARACTERIZATION OF RANGE SITES

Oliveira, José Gerardo Beserra de January 1979 (has links)
No description available.

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