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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

Hydrology and Water Resources in Arizona and the Southwest, Volume 17 (1987)

18 April 1987 (has links)
Complete issue of the Proceedings of the 1987 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 18, 1987, Northern Arizona University, Flagstaff, Arizona / Missing pages 49 & 50 from original
242

A Model of Snowpack Dynamics in Forest Openings

Ffolliott, Peter F., Guertin, D. Phillip, Rasmussen, William O. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
243

Factors Affecting Seasonal and Annual Precipitation in Arizona

Karnieli, Arnon, Osborn, Herbert B. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona / Seasonal and annual precipitation vary considerably in Arizona, primarily because of topographic influences. Precipitation data have been analyzed by several investigators over the years. Arizona has been subdivided into precipitation zones, and seasonal and annual precipitation isohyetal maps are available from several sources. Because of a paucity of raingages in the more mountainous regions, however, isohyetal lines in these regions have been largely estimated based on the assumptions of topographic influences. Now, with 158 raingages with 30 or more years of record, topographic factors can be combined with greater knowledge of the sources and paths of moisture into the state to better define annual and seasonal precipitation variability. Elevation and aspect appear to be the principal parameters for analyzing precipitation within the state, with the Mogollon Rim exerting the greatest influence on winter precipitation. Higher than anticipated summer rainfall in southeastern Arizona (based on elevation and aspect) suggest that sources and availability of atmospheric moisture may be a strong parameter in analyzing summer rainfall.
244

Mapping the Areal Precipitation over Arizona - Using Kriging Technique

Karnieli, Arnon 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona / The classical methods for interpolating and spatial averaging of precipitation fields fail to quantify the accuracy of the estimate. On the other hand, kriging is an interpolation method for predicting values of regionalized variables at points (punctual kriging) or average values over an area (block kriging). This paper demonstrates the use of the kriging method for mapping and evaluating precipitation data for the state of Arizona. Using 158 rain gage stations with 30 years or more of record, the precipitation over the state has been modeled as a realization of a two dimensional random field taking into consideration the spatial variability conditions. Three data sets have been used: (1) the mean annual precipitation over the state; (2) the mean summer rainy season; and (3) the mean winter rainy season. Validation of the empirical semi-variogram for a constant drift case indicated that the exponential model was appropriate for all the data sets. In addition to a global kriging analysis, the data have been examined under an anisotropic assumption which reflects the topographic structure of the state.
245

Initial Survival and Growth of Tree Seedlings in a Water Harvesting Agrisystem

Ffolliott, Peter F. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
246

Relationship Between Soil Spectral Properties and Sand, Silt, and Clay Content of the Soils on the University of Arizona Maricopa Agricultural Center

Suliman, Ahmed S., Post, Donald F. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
247

Accumulation of Heavy Metals and Petroleum Hydrocarbons in Urban Lakes: Preliminary Results

Amalfi, Frederick A., Sommerfeld, Milton R. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona / A preliminary survey of several urban lakes in the Phoenix metropolitan area was undertaken to assess the degree of accumulation of priority pollutant metals and petroleum -based hydrocarbons in these impoundments. Three sediment samples were collected from each lake along a transect (from a probable point of stormwater addition to the opposite shore), and were composited on an equal weight basis prior to analysis. Total petroleum hydrocarbon concentrations ranged from 30 to 8000 mg /kg dry weight. The concentration ranges (mg /kg dry weight) of total metals were: arsenic 7-26, copper 25-2800, chromium 14-55, nickel 5-40, lead < 1-138, selenium < 0.5-1.1, and zinc 33-239. Silver and cadmium were undetectable (< 5.0 and < 0.5 mg /kg, respectively). Factors that may be associated with the magnitude of accumulation in urban lakes include lake age, primary source of influent, reception of stormwater runoff, mechanical aeration of the water, and direct chemical addition.
248

The Qanats of Yazd

Zauderer, Jeffrey 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
249

The Second Management Plan: A Management Strategy for the 1990s

Jacobs, Katharine L. 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona
250

The Phoenix Water Resource Plan - 1987

Regil, Phil 16 April 1988 (has links)
From the Proceedings of the 1988 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 16, 1988, University of Arizona, Tucson, Arizona / The Phoenix Water Resource Plan-1987 is the official water resource plan for the City of Phoenix, Arizona. It covers the areas of supply, demand management and supply augmentation. The plan also addresses the issue of drought management.

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