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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.
1

Ten-year resurvey of epidermal browning and population structure of saguaro cactus (Carnegiea gigantea) in Saguaro National Park

Turner, Dale S. Funicelli, Carianne S. January 1900 (has links)
"October 2000." / Includes bibliographical references (p. 23-25).
2

Critical factors during the first years of life of the saguaro (Cereus giganteus) at Saguaro National Monument

Steenbergh, Warren F. January 1967 (has links)
No description available.
3

SUMMER HABITAT AND NEST SITE SELECTION OF ELF OWLS (MICRATHENE WHITNEYI) AT SAGUARO NATIONAL MONUMENT, ARIZONA (SONORAN-DESERT, HABITAT USE).

Goad, Mary Susanna. January 1985 (has links)
No description available.
4

Nocturnal rodent populations and associated vegetation with implications of human use at Saguaro National Monument, Arizona

Duncan, Douglas Keith, 1960- January 1989 (has links)
I obtained densities of nocturnal rodents in the saguaro (Carnegiea gigantea) forest of Saguaro National Monument, Arizona with live trapping techniques, in 1984 and 1985. I sampled vegetation density, percent cover, and foliage height diversity. My objective was to determine if humans influenced nocturnal rodents and their habitat. Rodent populations and vegetation were analyzed through 2-way analysis of variance. Few significant differences were determined for rodent numbers between experimental and control plots. My findings show that minimal impact has occurred on rodent populations and on vegetation by humans in Saguaro National Monument.
5

Traditional Saguaro Harvest in the Tucson Mountain District, Saguaro National Park

Toupal, Rebecca, Stoffle, Richard W., Dobyns, Henry 15 December 2006 (has links)
The overall objective for this report is to examine the Tohono O'odham people's traditional gathering and use of saguaro fruit in the Tucson Mountain District (TMD) of Saguaro National Park (SAGU). It is intended to aid park planning and environmental assessment work, as well as other related management decisions. Potential use of this report includes updating and informing the park's cultural and natural resource programs, and public education programs. Based on tribal concerns, the focus of the study shifted to the existing harvest camps in TMD, an ethnohistory of harvest in TMD, and an ethnobotany of the saguaro. The 2004 harvest season provided our only access to field interactions with harvesters, however, it was a year of poor production and only a handful of people came to the camp in TMD. The ethnography, consequently, was limited to two individuals, one of whom wrote her account privately. Both women came from families with an unbroken saguaro harvest tradition and have continued the practice with their immediate families. The report includes an ecological overview of the saguaro, an ethnohistory of the saguaro harvest and harvest camp in the TMD, and an ethnobotany of the saguaro. A final management discussion includes impacts, traditional knowledge, and suggestions from the study participants.
6

Floristic surveys of Saguaro National Park protected natural areas

Halvorson, William L. Gebow, Brooke S. January 1900 (has links)
"October 2000." / Includes bibliographical references (p. 46).
7

Long Term Effects of Cattle Grazing on Age Distribution in a Population of Carnegiea gigantea in Saguaro National Park

January 2013 (has links)
abstract: Livestock-grazing, in particular cattle grazing, is a common use of public and private lands in western North America. As a result, the effects of grazing on both plants and animals are widely studied. Few studies, however, look directly at the long-term effects that cattle grazing may have on a particular species. The goal of this experiment was to continue research begun in 1988, to determine if the effects of cattle grazing are still seen in the age structure of two populations of saguaros (Carnegiea gigantea [Engelm.] Britton & Rose) at Saguaro National Park - Rincon Mountain District (SNP-RMD). The null hypothesis stated that enough time has elapsed since the cessation of grazing, and there is no difference in the age distribution of the saguaros of the two populations. The study area was comprised of a former fence line where grazing ceased on the western side of the fence in 1958 and the eastern side in 1978. Belt transects were laid on each side of the fence line and height was measured for each saguaro encountered in a transect. Approximate age of the individual was then calculated using an age-height correlation for SNP-RMD. Individuals were then placed into age classes of 10 year increments and a Log-Likelihood test was performed. The resulting calculated P value of 0.12 meant the null hypothesis was not rejected and there was no statistical difference between the age structure of the two populations. After 34 and 54 years rest from grazing, the negative effects of cattle grazing on the retention and recruitment of saguaro seedlings have ended, and replenishment of the populations is now dependent upon factors such as temperature and precipitation. Other factors such as climate change, increasing fire frequency, encroachment by invasive species, and poaching are sources of concern and increased mortality for these and other saguaros. / Dissertation/Thesis / M.S. Applied Biological Sciences 2013
8

An evaluation of hydrologic and riparian resources in Saguaro National Park, Tucson, Arizona

Baird, Kathryn J., Mac Nish, Robert, Guertin, D. Philip January 2001 (has links)
Cooperation Agreement No. CA 8000 -2 -9001 Work Order No. 8039 -2 -9001 / Within Saguaro National Park only Rincon Mountain District contains significant riparian areas. The geologic framework of the Tanque Verde Ridge and Rincon Valley exerts strong control on the hydrology of these riparian systems. Pantano fault constitutes a line of hydrogeologic separation between the occurrence and utilization of groundwater in the Rincon Valley and the main Tucson basin. No known, comparable fault isolates the upper Tanque Verde Creek alluvium from downstream pumping effects. However, east of the confluence with Agua Caliente Wash, the highly permeable alluvial materials are much thinner, and serve to dampen such downstream effects. Therefore, the ground water reservoirs supporting the riparian areas within Rincon Mountain District are not directly connected to the Tucson basin aquifer. In what is described herein as upper basin areas, high gradient tributary streams to Tanque Verde Creek and Rincon Creek have discontinuous bodies of shallow alluvium interspersed with bedrock channel. Alluvium has accumulated behind small faults or resistant bedrock ledges and contains shallow ground water basins that support small pockets of riparian or xeroriparian vegetation. The ground water in these small basins is sustained by seeps or springs, and by runoff from precipitation and is not likely to be connected to a regional ground water system. In what we have characterized as middle basin areas, the stream gradients are less than 25m/km. In these low gradient reaches, the alluvial floodplain sediments are continuous, though not thick, as ledges of more resistant bedrock formations appear in the stream channel. These low gradient reaches contain larger volumes of ground water than the high gradient basins and support more robust riparian vegetation. The ground water in the low gradient reaches is believed to be connected to the regional ground water system. Such a low gradient reach exists in a tributary to Tanque Verde Creek about 1.4 km east of Wentworth Road and extends about 1.6 km into the Park. A similar low gradient reach occurs along Rincon Creek in the Expansion Area, and at the mouths of Chiminea and Madrona Creeks.
9

Cattle Grazing in the National Parks: Historical Development and History of Management in Three Southern Arizona Parks

Pinto, Robin Lothrop January 2014 (has links)
This dissertation traces the history of cattle grazing at Saguaro NP, Organ Pipe Cactus NM and Fort Bowie NHS in southern Arizona. This collection of studies examines the factors affecting that use, the ranchers who made their living from the landscape, and the federal land managers responsible for sustaining the natural and cultural resources. A dominant industry on arid public lands since the Civil War, grazing was altered by a variety of influences: environmental and human-derived. Ranching communities developed from homesteading settlements. Success was determined by climate, topography, and natural resources; social and cultural pressures; economic events and political legislation; and later federal regulations and decisions. The first agency to oversee grazing, USFS was under constant pressure to maximize short-term human benefits. The NPS Organic Act of 1916 mandated conservation of natural resources "by such means as will leave them unimpaired for future generations" and yet approved cattle grazing, an extractive use, under USFS management. Park managers were frustrated by grazing practices not under their control. Parks were at a cultural and social disadvantage. Residents and politicians often expressed displeasure at park reservations; communities feared that parks would interfere with local industries. Park employees supervised visitors and developed recreation infrastructure; they came with little experience to manage livestock. Lack of funding for research, limited manpower, and political and administrative interference allowed cattle grazing to continue unregulated for decades altering vegetation and enhancing erosion. In the 1960s, changing values from the environmental movement, the waning power of the livestock industry, and the rise of activist scientists impelled NPS to act. Without monitoring data, NPS turned to legal opinions to terminate grazing. Now grazing is regulated and carefully monitored. NPS is mandated to incorporate research results into management decisions. Older grazing permits are being retired, but land acquisitions for park additions add new management challenges. Purchasing permits offers a new but financially limited opportunity to protect sensitive lands. Grazing has ended at all three parks, yet ecological changes and historic structures remain. As cultural and administrative legacies, those remnants offer opportunities to interpret a significant regional tradition and an untold controversy.

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