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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

Agricultural adjustments to a falling groundwater table in central Arizona.

Hock, Kenneth John,1934- January 1973 (has links)
The level of future agricultural production in Central Arizona depends upon the availability of land and water, the cost of water, and opportunities to grow crops yielding high returns per acre-foot of water. Suitable land is abundantly available but groundwater appurtenant to these lands is becoming increasingly costly. Opportunities to grow high-value crops are subject to the vagaries of commodity markets and government programs. This study estimates the direction and magnitude of expected agricultural adjustments in response to a declining land and water base, increasing water costs, and intra-county transfer of cotton allotments. The study region, encompassing all areas of Maricopa County relying solely or primarily upon groundwater for irrigation, is divided into two water resource areas. Area A has low-cost, poor quality water and only cotton for a high-value crop. Area B has highcost, good quality water and cotton, vegetables, and citrus for highvalue crops. Nine representative farm models are developed characterizing the structure of the agricultural sector of the economy in these two areas. Data for ten crops grown by these nine farm size groups are incorporated into linear programming models to make projections for 18 water situations distinguished on the basis of source, availability, and cost of water. Projections are made for the period 1967 to 2015. Projected adjustments show over 20 percent declines in land and water use and a 13 percent decline in net revenues over variable costs of production for the study region by 2015. These declines occur due to a loss of 68,000 acres of land to urban uses, and the abandonment of lowvalue crops made unprofitable by rising water costs. Declines in resource use and incomes are mitigated by a 10,000 acre increase in cotton production due to transfers of allotments from an adjacent region experiencing greater losses of land and water to urban uses. Projections by water resource area and water situation show 7 and 13 percent decreases in land and water use and a 7 percent increase in net revenues over variable costs for Area A. This divergent movement of resource use and revenues occurs because a 64 percent increase in cotton acreage offsets substantial reductions in sorghum and safflower acreages. Area B projections show approximately a 30 percent reduction in land and water use and a 23 percent reduction in net revenues over variable production costs. These reductions occur because all resources lost to urban uses come from this area and large acreages of low-value crops go out of production due to rising water costs. Only small acreages of short staple cotton allotments are transferred to Area B farms because Area A farmers can afford to pay more for surplus allotments. Area B experiences a net loss of cotton acreage because long staple allotments are transferred to Area A ferns when water costs make this variety of cotton unprofitable in Area B water situations. Projections by water situation within the two water resource areas vary from increases in resource use and net incomes to large decreases. The agricultural sector of Maricopa County expands until 1960, then enters a stage of decline, accelerated by large losses of land and water resources to urban uses in one irrigation district with adequate supplies of low-cost water. A comprehensive land use plan with zoning restrictions preventing urbanization of low-cost water areas would help maintain agricultural resource use and incomes at levels higher than will otherwise occur. Such a plan would also help maintain the quality of Che urban environment in Maricopa County.
32

Near real-time irrigation scheduling using the Bowen ratio technique

Yagi, Kazuhiko, 1957- January 1989 (has links)
The actual evapotranspiration rate for wheat at the Campus Agriculture Center (CAC) and alfalfa at the Maricopa Agricultural Center (MAC) were measured using the Bowen ratio technique for near real-time irrigation scheduling. The Bowen ratio method underestimated evapotranspiration when compared with AZMET and Penman data. There were problems with the hygrometer and the net radiometer which might have caused this underestimation. The height-fetch ratio requirement was not met, and this may have affected the data. Irrigation scheduling programs and the technique to schedule irrigation in a near real-time were developed. Irrigation programs were not field tested because of the problem with field data. Simulated data was successfully used to demonstrate its application. It was found that irrigation could be scheduled in a near real-time with the programs provided reliable data and proper data acquisition systems are used.
33

Geotechnical characterization of an alluvial fanglomerate

Chen, Daqin, 1958- January 1988 (has links)
The Department of Energy (DOE) has recently announced that the Superconducting Super Collider (SSC) will soon be built somewhere in the United States. Preliminary geophysical studies indicate that the Sierrita site 35 miles southwest of Tucson has geological conditions that would facilitate construction of the SSC. The Maricopa site southwest of Phoenix is also one of the two potential sites in Arizona. However, several additional geotechnical investigations were required to convincingly demonstrate the suitability of these two locations. The present research program identified the geotechnical properties of the soils at the two sites through various levels of laboratory and field testing. The significance of these results are discussed and recommendations are given.
34

Soil Survey in Salt River Valley

Means, Thos. H. 05 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
35

Plan of Study for a Demonstration Recharge Project in the Salt River Valley

United States Army Corps of Engineers., University of Arizona. Water Resources Research Center., University of Arizona. School of Renewable Natural Resources. 09 1900 (has links)
Cover title: Draft technical appendix. / Phoenix Urban Study: Final Report / The work upon which this publication is based was supported by funds provided by the U.S. Army Corps of Engineers, Los Angeles District, as authorized by resolution of the Senate Public Works Committee on July 31, 1973. This report was prepared as a contribution to the Phoenix Urban Study under auspices of the U.S. Army Engineer District, Los Angeles.
36

An exploration gravity survey of the south basin of Vekol Valley, Pinal and Maricopa Counties, Arizona

Davis, Stanley Graham January 1984 (has links)
No description available.
37

Casa Grande Ruins National Monument Foundations for Cultural Affiliation

Zedeno, Maria Nieves, Stoffle, Richard W. January 1995 (has links)
This report summarizes information on the prehistoric, historic, and ethnographic foundations for the cultural affiliation of burials and associated funerary objects from Casa Grande Ruins National Monument in Casa Grande, Arizona. This study was commissioned by the National Park Service’s Applied Ethnography Program in Washington, D.C., to identify American Indian tribes potentially affiliated with the human remains and associated funerary objects from Casa Grande Ruins National Monument. This study is one of the responses by the National Park Service to the requirements stipulated in the Native American Graves Protection and Repatriation Act of 1990. The report should provide sufficient criteria for determining potentially affiliated individuals and tribes to be contacted for future consultation. This research determined the following Native American ethnic groups are affiliated to the national monument: Akimel O'odham, Tohono O’Odham, Zuni, Hopi, and Maricopa.
38

EXTRACTION OF SURFACE AND SUBSURFACE GEOLOGIC INFORMATION FROM DIGITAL IMAGES OF THE PROPOSED ARIZONA SUPERCONDUCTING SUPER COLLIDER SITES (REMOTE SENSING)

Poulton, Mary Moens, 1962- January 1987 (has links)
No description available.
39

Geotechnical investigations of two potential sites for the proposed Arizona superconducting super collider

Glynn, Mary Eileen, 1960- January 1987 (has links)
Two sites around the Maricopa and Sierrita Mountains respectively were investigated to provide supporting data for the State of Arizona proposal to the Department of Energy to construct a Superconducting Super Collider (SSC) facility. The main feature of the facility is a 53 mile racetrack shaped tunnel. The proposed Maricopa SSC tunnel passes through three main types of rock--approximately 35 miles of indurated fanglomerates, 10 miles of granodiorites and 8 miles of volcanic and sedimentary rocks. The proposed Sierrita SSC tunnel also passes through three main rock types--approximately 19 miles of indurated fanglomerates, 18 miles of granodiorites and granites and 16 miles of volcanic and associated rocks. Data were obtained from three sources--existing data; field investigations including drill logs and geophysics and laboratory testing. Empirical design approaches were compared with rock classifications (RQD, RMR, Q) at the tunnel horizon. Results indicate mostly routine tunneling at both sites. Recommendations are made for: further logging and testing of existing core; further field mapping; additional boreholes in rock and alluvium; and in situ testing of alluvium.
40

Effectiveness of a multimedia approach in the prevention of iron deficiency anemia for parents of preschool children

LeMay, Ruth Rosa, 1937- January 1978 (has links)
No description available.

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