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Articles 5671 - 5700 of 7341

Full-Text Articles in Physical Sciences and Mathematics

Experimental Evidence For The Acceleration Of Thermal Electrons By Ion Cyclotron Waves In The Magnetosphere, A. J. Norris, J.F. E. Johnson, Jan Josef Sojka, G. L. Wrenn, N. Cornilleau-Wehrlin, S. Perraut, A. Roux Jan 1983

Experimental Evidence For The Acceleration Of Thermal Electrons By Ion Cyclotron Waves In The Magnetosphere, A. J. Norris, J.F. E. Johnson, Jan Josef Sojka, G. L. Wrenn, N. Cornilleau-Wehrlin, S. Perraut, A. Roux

All Physics Faculty Publications

Ion cyclotron waves (ICWs) at frequencies just above f He+ , the helium gyrofrequency, are often observed by the ESA satellites GEOS 1 and GEOS 2. Young et al. (1981) have shown the close connection between these ICWs and the presence of thermal He+ ions in the outer magnetosphere. The purpose of this paper is to provide experimental evidence for the acceleration of thermal electrons by the large amplitude ICWs. The wave power in the ultra low frequency (ULF) range near f He+ is compared with the distribution function of low energy electrons, measured by instruments aboard the GEOS satellites. …

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Preferential Perpendicular Acceleration Of Heavy Ionospheric Ions By Interactions With Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka Jan 1983

Preferential Perpendicular Acceleration Of Heavy Ionospheric Ions By Interactions With Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

The energization of heavy ionospheric ions by electrostatic hydrogen cyclotron (EHC) waves is examined. In particular, the problem of preferential perpendicular acceleration of heavy ions above 5000 km along auroral field lines is examined critically. Observations have indicated that above this altitude the occurrences of ion beams and EHC waves are highly correlated and that the occurrence rates are high. The EHC waves are found to be coherent. The energization process is examined in the light of interactions of a single coherent wave with the ions. The interactions can be stochastic or nonstochastic, depending on the parameters of the wave …

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A Preliminary Quantification Of The Impacts Of Aspen To Conifer Succession On Water Yield Within The Colorado River Basin (A Process Aggravating The Salt Pollution Problem), Gerald F. Gifford, William Humphries, Richard A. Jaynes Jan 1983

A Preliminary Quantification Of The Impacts Of Aspen To Conifer Succession On Water Yield Within The Colorado River Basin (A Process Aggravating The Salt Pollution Problem), Gerald F. Gifford, William Humphries, Richard A. Jaynes

Reports

Heat pulse velocity techniques were developed for effectively monitoring water movement in aspen (Populus ttremuloides), subalpine fir (Abies lasiocarpa), and Englemann spruce (Picea engelmannii). Once the techniques were perfected, transpiration was monitored in replicated trees of each species for one year. This data was used to modify the plant activity index and the crop coefficient for each species within the model ASPCON, a deterministic, lumped-parameter model describing the hydrology of aspen to conifer succession. Results of the modeling indicate 18.5 cm(7.3 in) net loss of moisture available for stream flow when spruce replace aspen, and a loss of 7.1 cm …

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Effects Of Cadmium On Streams And Irrigated Agriculture In The Presence And Absence Of Oil Shale Leachate, Douglas A. Selby, Jean M. Ihnat, Fredrick J. Post, Jay J. Messer Jan 1983

Effects Of Cadmium On Streams And Irrigated Agriculture In The Presence And Absence Of Oil Shale Leachate, Douglas A. Selby, Jean M. Ihnat, Fredrick J. Post, Jay J. Messer

Reports

Artificial streams, soil perfusion columns, and potted plants were exposed to 20 ug Cd/l in the presence and absence of unretorted oil shale leachate. High cadmium accumulations occurred in the stream biota, but did not measurably affect community structure or function. The presence of oil shale leachate had no effect on bioaccumulation or ecosystem structure or function. Nitrification in soil columns was enhanced by the presence of the organic fraction of oil shale leachate, but this effect was not observed when cadmium was present. Crop accumulation of cadmium was somewhat higher in alfalfa and radishes irrigated with leachate, but did …

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Drought Management Concepts: Lessons Of The 1976-1977 U.S. Drought, Rangesan Narayanan, Herbert H. Fullerton, Trevor C. Hughes, A. Bruce Bishop, Mac Mckee, Dean T. Larson, Hamid Fakhraei Jan 1983

Drought Management Concepts: Lessons Of The 1976-1977 U.S. Drought, Rangesan Narayanan, Herbert H. Fullerton, Trevor C. Hughes, A. Bruce Bishop, Mac Mckee, Dean T. Larson, Hamid Fakhraei

Reports

Three approaches to drought management are developed as generalized mathematical models. Each model is then applied to particular locations in Utah using the hydrologic/economic data from the 1976-77 drought. The modeling approaches include: (1) A multiple regression approach is used to quantify the changes in water use achieved by three common municipal sector rationing policies: (a) restrictions on time of outdoor use, (b) price increases, and (c) mandatory quantity restrictions (2) A model was presented for determing the optimal long term price schedule for rationing a stochastically variable water supply during summer peak demand season among groups of municipal water …

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Adapting Appropriation Water Law To Accommodate Equitable Consideration Of Instream Flow Uses, Jay M. Bagley, Dean T. Larson, Lee Kapaloski Jan 1983

Adapting Appropriation Water Law To Accommodate Equitable Consideration Of Instream Flow Uses, Jay M. Bagley, Dean T. Larson, Lee Kapaloski

Reports

The increasing public interest in naturally flowing streams has fostered efforts to obtain their protection under existing state water laws. In this study, the water laws of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming were examined and compared 1) with each other, and 2) against a set of aleitn criteria, to assess shortcomings in accommodating instream flow protections. It was determined that the appropriation system has the essential features of and ambodies legal principles that should allow the accommodation of instream flow values but, at this time, purchase of existing rights or the exercise of governmental reservation/withdrawal/appropriation …

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Incoherent Scatter Measurements Of Ion-Neutral Collision Frequencies And Temperatures In The Lower Thermosphere Of The Auroral Region, C. Lathuillere, Vincent B. Wickwar, W. Kofman Jan 1983

Incoherent Scatter Measurements Of Ion-Neutral Collision Frequencies And Temperatures In The Lower Thermosphere Of The Auroral Region, C. Lathuillere, Vincent B. Wickwar, W. Kofman

All Physics Faculty Publications

Incoherent scatter observations performed in March and November 1978 at Chatanika have been used for studying the lower thermosphere in the auroral region. Neutral temperatures and densities have been found during periods without Joule heating. We present mean profiles of temperatures and collision frequencies (approximately proportional to neutral densities) for each month and profiles obtained during four specific nights. Between 93 km and 110 km the mean profiles of temperature are in good agreement with the Jacchia (1971) model, and the profiles of collision frequency are similar to those deduced from the model. Consistency checks between these collision frequencies and …

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Comparison Of Model High-Latitude Electron Densities With Millstone Hill Observations, Jan Josef Sojka, Robert W. Schunk, J. V. Evans, J. M. Holt, R. H. Wand Jan 1983

Comparison Of Model High-Latitude Electron Densities With Millstone Hill Observations, Jan Josef Sojka, Robert W. Schunk, J. V. Evans, J. M. Holt, R. H. Wand

All Physics Faculty Publications

Model predictions of the diurnal variations of plasma convection velocities and electron densities in the high-latitude ionosphere were compared with Millstone Hill incoherent scatter radar observations for an equinox day on which there was moderate magnetic activity. On the observation day, three major morphological features were evident at 500 km, including a dayside high density region, a nightside mid-latitude trough, and a region of slightly enhanced densities in the auroral zone. Although the dayside high density region was due to solar EUV radiation, it was not symmetrical about local noon (1000-1900 LT sector) owing to the effect of horizontal transport. …

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Large-Scale Counterstreaming Of H+ And He+ Along Plasmaspheric Flux Tubes, P. G. Richards, Robert W. Schunk, Jan Josef Sojka Jan 1983

Large-Scale Counterstreaming Of H+ And He+ Along Plasmaspheric Flux Tubes, P. G. Richards, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

An interhemispheric plasma transport model has been used to study the flow characteristics of H+, He+, and O+ along closed geomagnetic field lines for solstice conditions at noon local time. The calculations were carried out for the flux tube that passes through Millstone Hill. Both symmetric and asymmetric neutral winds in the conjugate ionospheres were considered. Initially, the flux tube content was partially depleted, and the subsequent refilling was studied until a steady state flow was established between the winter and summer hemispheres. The main conclusion to be drawn from this study is that H+-He+ counterstreaming can be expected along …

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Fluorescence Quenching At High Quencher Concentrations, David Peak, T C. Werner, R M. Dennin Jr., J K. Baird Jan 1983

Fluorescence Quenching At High Quencher Concentrations, David Peak, T C. Werner, R M. Dennin Jr., J K. Baird

All Physics Faculty Publications

Chemical reactions occurring in dense media at high reactant concentrations can be described by rate ‘‘constants’’ which are actually functions of concentration. We present a theoretical model in which this so‐called rate constant ‘‘renormalization’’ occurs for the specific case of fluorescence quenching in solution. We show that both the quenching and the excitation rate constants can become concentration dependent. We fit our theory to several sets of experimental data—our own and some from the literature—and show that excellent agreement is obtained by varying a single free parameter, namely, the efficiency with which a fluorophore‐quencher collision leads to a quench of …

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Characteristics Of Thermal And Suprathermal Ions Associated With The Dayside Plasma Trough As Measured By The Dynamics Explorer Retarding Ion Mass Spectrometer, Jan Josef Sojka, Robert W. Schunk, J.F. E. Johnson, J. H. Waite, C. R. Chappell Jan 1983

Characteristics Of Thermal And Suprathermal Ions Associated With The Dayside Plasma Trough As Measured By The Dynamics Explorer Retarding Ion Mass Spectrometer, Jan Josef Sojka, Robert W. Schunk, J.F. E. Johnson, J. H. Waite, C. R. Chappell

All Physics Faculty Publications

The retarding ion mass spectrometer (RIMS) instrument on Dynamics Explorer 1 has carried out high-altitude measurements of the polar wind. During an outbound pass through the outer plasmasphere and plasma trough at 0900 LT the RIMS instrument measured the detailed characteristics of the thermal and suprathermal ions. Three distinct populations were observed: (1) thermal ions (H+ and He+) with densities ranging from > 500 ions/cm3 to < 1 ion/cm3, temperatures around 2 eV (20,000° K), and H+/He+ density ratios of 2 to 4, (2) warm anisotropic plasma with densities ranging from 2 to 12 ions/cm …

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A Theoretical Study Of The High Latitude F Region’S Response To Magnetospheric Storm Inputs, Jan Josef Sojka, Robert W. Schunk Jan 1983

A Theoretical Study Of The High Latitude F Region’S Response To Magnetospheric Storm Inputs, Jan Josef Sojka, Robert W. Schunk

All Physics Faculty Publications

The response of the polar ionosphere to magnetospheric storm inputs was modeled. During the storm the two major processes that couple the F region to the magnetosphere, namely the electric field distribution and the particle precipitation from the magnetosphere, undergo drastic modification on relatively short F region time scales. These time-dependent changes are not simply related to the F region storm time dependent changes. The lower F region responds on a time scale of only minutes to the storm associated changes in the auroral precipitating electron flux, owing to the dominance of chemistry production-loss mechanisms over transport processes. At higher …

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Impediments To Effective Interactions Between Multipurpose Water Districts And Other Governmental Institutions In Urbanizing Areas, Jay M. Bagley, Frank W. Haws, Wendell B. Anderson, Daniel H. Hoggan, Lee Kapaloski Jan 1983

Impediments To Effective Interactions Between Multipurpose Water Districts And Other Governmental Institutions In Urbanizing Areas, Jay M. Bagley, Frank W. Haws, Wendell B. Anderson, Daniel H. Hoggan, Lee Kapaloski

Reports

Water institutions are highly diffused throughout society. These institutions interact with one another in various ways. As water needs and services expand, collaborative and cooperative arrangements are commonly sought as a means of meeting common goals of providing a safe, dependable adn least cost water supply to particular constituencies. Of the many different institutions involved in the development, managment, distribution, and use of water, perhaps the most significant in terms of extensive interactions with other institutions is the kind that is typified by Water Conservancy Districts and Metropolitan Water Districts in Utah. The statutory and operating framework of counterpart organizations …

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Aquatic Resources Management Of The Colorado River Ecosystem, V. Dean Adams, Vincent A. Lamarra Jan 1983

Aquatic Resources Management Of The Colorado River Ecosystem, V. Dean Adams, Vincent A. Lamarra

Reports

The Colorado River system has often been referred to as "the most regulated river system in the world." The Colorado River Basin serves millions of people through agricultural, energy, municipal and industrial uses, fish and wildlife activities, and recreation. The symposium was conceived and organized to allow researchers, private industry, consultants, water users, regulatory agencies, and concerned citizens the opportunity to express needs, desires, and concerns about the vast resources of the Colorado River. We found that there were a diverse number of problems confronting the individuals who are involved in the management of this important ecosystem. A variety of …

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Fecal Coliform Release Studies And Development Of A Preliminary Nonpoint Source Transport Model For Indicator Bacteria, Everett P. Springer, Gerald F. Gifford, Michael P. Windham, Richard Thelin, Michael Kress Jan 1983

Fecal Coliform Release Studies And Development Of A Preliminary Nonpoint Source Transport Model For Indicator Bacteria, Everett P. Springer, Gerald F. Gifford, Michael P. Windham, Richard Thelin, Michael Kress

Reports

The effect of grazing on water quality has been documented by bacteriological studies of streams adjacent to grazed areas. Bacterial release from fecal deposits is a parameter of the pollution transport mechanism that is poorly understood. The objective of this study was to determine a fecal coliform release function for cattle fecal deposits. Standard cowpies were rained on with a rainfall simulator, and the fecal coliform counts were determined using the most probably number (MPN) method of enumeration. The fecal deposits were rained on at ages 2 through 100 days. The effects of rainfall intensity and recurrent rainfall were tested. …

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Hydrologic Evaluation Of The Coastal Belt Water Project Sarir And Tazerbo Well Fields, Libya, Edward P. Fisk, Christopher J. Duffy, Calvin G. Clyde, Roland W. Jeppson, Phillip H. Degroot, Bhasker Rao K., Win-Kai Liu Jan 1983

Hydrologic Evaluation Of The Coastal Belt Water Project Sarir And Tazerbo Well Fields, Libya, Edward P. Fisk, Christopher J. Duffy, Calvin G. Clyde, Roland W. Jeppson, Phillip H. Degroot, Bhasker Rao K., Win-Kai Liu

Reports

Executive Summary: The basic purpose of this study was to conduct a finite-element computer model and give an dindependent appraisal of the reliability of the groundwater supply for the proposed Coastal Belt Water Project (CBWP_ Well Fields at Sarir and Tazerbo. There is no doubt that ample quantities of groundwater of acceptable quality occur at the sites selected for these well fields for the estimated 50-year life of the project and longer. Of major concern is the predicted drawdown of wells and total pumping lifts throughout the 50-year period. Excessive drawdowns could cause operating costs to become prohibitibely expensive. Average …

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Polycyclic Aromatic Hydrocarbons: Are They A Problem In Processed Oil Shales?, David L. Maase, V. Dean Adams Jan 1983

Polycyclic Aromatic Hydrocarbons: Are They A Problem In Processed Oil Shales?, David L. Maase, V. Dean Adams

Reports

Organic residues from processed oil shales were characterisized with specific attention to polycyclic aromatic hydrocarbons (PAH). Oil shale development in the White River Basin (Utah and Colorado) was projected and hydrological and geological parameters pertinent to estimations of polycyclic aromatic hydrocarbons (PAH) flux were focused. Oil shale samples from the Union B, Paraho, and Tosco II processes were extracted by using organic solvents in a soxhlet apparatus and by mixing shale samples with water (characterization in

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The Evaluation Of Metals And Other Substances Released Into Coal Mine Accrual Waters On The Wasatch Plateau Coal Field, Utah, Alberta J. Seierstad, V. Dean Adams, Vincent A. Lamarra, Nancy J. Hoefs, Robert E. Hinchee Jan 1983

The Evaluation Of Metals And Other Substances Released Into Coal Mine Accrual Waters On The Wasatch Plateau Coal Field, Utah, Alberta J. Seierstad, V. Dean Adams, Vincent A. Lamarra, Nancy J. Hoefs, Robert E. Hinchee

Reports

Six sites on the Wasatch Plateau were chosen representing subsurface coal mines which were discharging or collecting accrual water on this coal field. Water samples were collected monthly at these sites for a period of 1 year (May 1981 to April 1982). Samples were taken before and after each mine's treatment system. Water sampels were analyzed for major anions and cations, trace metals, physical properaties, nutrients, total organic carbon, oil and grease, trihalomethanes, and algal assay. Predictions were made as to the possible effects these coal mine accrual waters would have when used for drinking water, irrigation water, stock and …

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Index Construction For Multiple Objective Analysis Of Land And Water Use In A High Mountain Watershed, L. Douglas James, Dean T. Larson, Mac Mckee, Jay J. Messer, Thomas M. Twedt, Randy Sperger, Barbara D. Campion, Frank J. Nemanich, Donald B. Porcella, Herbert H. Fullerton Jan 1983

Index Construction For Multiple Objective Analysis Of Land And Water Use In A High Mountain Watershed, L. Douglas James, Dean T. Larson, Mac Mckee, Jay J. Messer, Thomas M. Twedt, Randy Sperger, Barbara D. Campion, Frank J. Nemanich, Donald B. Porcella, Herbert H. Fullerton

Reports

Comprehensive planning is an elusive ideal. The practical planner must sort the relevant information from the vast amounts of data that modern technology can collect. The objective of this study was to use the Upper Blackfoot watershed in the mountains of Southeastern Idaho as an arena for developing methods for construction, refinement, and application of indices needed to design land and water management schemes, compare alternatives, and influence the public in their uses of the area. A total of 21 uses were examined on 242 land units of a 160 square-mile area ranging in elevation from 6300 to 9000 feet …

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An Economic Evaluation Of Benefits And Costs Of Maintaining Instream Flows, Rangesan Narayanan, Dean T. Larson, A. Bruce Bishop, Parvaneh Amirfathi Jan 1983

An Economic Evaluation Of Benefits And Costs Of Maintaining Instream Flows, Rangesan Narayanan, Dean T. Larson, A. Bruce Bishop, Parvaneh Amirfathi

Reports

Instream flows enhance recreation, hydropower, fish and wildlife maintenance, and riverine ecosytems. Each use has water requirements that vary over time in unique patterns. The determination of the overall instream requirement at any given time must be considered in competition with the demand for municipal and agricultural uses. Two obstacles to integrating instream uses into the appropriation system of water law are difficulty in satisfying the legal requirements of an appropriation for a public use and the fact that instream flow uses are considered more "environmental" than "economic" in character. The extreme options for allocating flow between these user groups …

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Hydraulics Of Solving Unsteady Debris Flow, Roland W. Jeppson, Salvador A. Rodriguez Jan 1983

Hydraulics Of Solving Unsteady Debris Flow, Roland W. Jeppson, Salvador A. Rodriguez

Reports

This report describes methods for determining the depths, velocities, and flow rates of debris flows. As used herein debris flow consists of water rand solid particles sot that the density of the mixture is roughly twice as large as water, and due to the accumulation of large solid particles the viscosity of the mixture is large enough for the flow to exhibit typical laminar flow properties in which adjacent layers slide with respect to each other rather than intermix as occurs in turbulent flows of water for example. A previous report from this project proposed a basic equation for estimating …

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Conjunctive Water Use Planning With Water Quality Constraints In Tooele Valley, Utah, Bhasker Rao K., Calvin G. Clyde, Rangesan Narayanan Jan 1983

Conjunctive Water Use Planning With Water Quality Constraints In Tooele Valley, Utah, Bhasker Rao K., Calvin G. Clyde, Rangesan Narayanan

Reports

The need for more efficient water management is gaining recognition due to the increased cost of water supply, the growth in the demand for water, and greater environmental and social impacts of water programs. "Conjunctive use" of surfact and groundwater resources provides opportunities for increasing net benefits to the water users. Past "conjunctive use" studies, however, have usually not included water quality constraints. In Tooele valley, Utah, spatial variation of groundwater qualtity (total dissolved solids) is significant. The areas of good (400-500 mg/1), fair (500-1,000 mg/1), and poor (1,000-3,000 mg/1) quality groundwaters were identified in an earlier study by the …

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Eutrophication Assessment Of Mt. Dell Reservoir, Richard A. Hanson, V. Dean Adams, Vincent A. Lamarra, Kyle R. Cook, Dennis B. George Jan 1983

Eutrophication Assessment Of Mt. Dell Reservoir, Richard A. Hanson, V. Dean Adams, Vincent A. Lamarra, Kyle R. Cook, Dennis B. George

Reports

The degree and possible causes of eutrophication in Mt. Dell Reservoir, a small water supply reservoir in Parleys Canyon above Salt Lake City, were examined with a number of limnological studes. These studies described external (incoming stream flow) and internal (sediment) nutrient sources, general limnology, nutrient limitations, and trophic state. A monthly program of sampling at selected stream sites determined taht one area of mixed agricultural and undistrubed rangeland contributed significant amounts of total soluble inorganic nitrogen. Sediment phosphorus uptake and release rates were determined with aquatic three-phase microcosms. The results indicated that sediment phosphorus mass loadings were small (less …

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Reconnaissance Of Sediment-Phosphorus Relationships In Some Utah Reservoirs, Jay J. Messer, Jean M. Ihnat Jan 1983

Reconnaissance Of Sediment-Phosphorus Relationships In Some Utah Reservoirs, Jay J. Messer, Jean M. Ihnat

Reports

Introduction: Phosphorus inputs to lakes and reservoirs from tributary streams and non-point sources are well-known contributors to nuisance algal growths that degrade water quality for potable and recreational uses in lakes and reservoirs. However, phosphours inputs to the euphotic zone may also occur from within the lake itself, as a result of releases from both oxic and anoxid sediments. Such releases may originate from phosphorus inputs to a lake or reservoir during high runoff periods in the previous winder or spring, or they may represent phosphorus trapped in the sediment many years earlier, when phosphorus contributions from natural or anthropogenic …

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Adapting Water Services To Urban Growth: A Case Study Of Salt Lake County, Dean T. Larson, Kirk R. Kimball, Calvin W. Hiibner, Jay M. Bagley Jan 1983

Adapting Water Services To Urban Growth: A Case Study Of Salt Lake County, Dean T. Larson, Kirk R. Kimball, Calvin W. Hiibner, Jay M. Bagley

Reports

Urbanizing areas thorughout the nation are considering governmental reorganization or consolidation to coordinate planning and improve the cost effectiveness of the delivery of public services. More efficient water supply and wastewater services may become important in the political debate over reorganization. However water factors figure politically, accomplished reorganizations must carefully plan for efficent provision of water services. This study profiles the structure and interactions of municipalities and water service agencies in Utah's Salt Lake County during the 1970s. Both 1975 and 1978 attempts to consolidate Salt Lake City and the unincorporated areas of the county failed. The voting patterns, interest …

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Evaluation Of The Potential For Groundwater Transport Of Mutagenic Compounds Released By Spent Oil Shale, Robert E. Hinchee, V. Dean Adams, Jeffrey G. Curtis, Alberta J. Seierstad Jan 1983

Evaluation Of The Potential For Groundwater Transport Of Mutagenic Compounds Released By Spent Oil Shale, Robert E. Hinchee, V. Dean Adams, Jeffrey G. Curtis, Alberta J. Seierstad

Reports

The major focus of this study was on the potential mutagenicity of aqueous leachates from spent oil shale. Additional mutagenicity testing was also done on raw shale and coal. The Ames salmonella microsomal bioassay was used to test for chemical mutagenicity. Spent oil sahles from the Paraho and TOSCO II processes, a raw shale from Anvil Points, and a composite coal sample from the Wasatch plateau were extracted with water and organic solvents. Only organic solvent extraction of the TOSCO spent shale resulted in a mutagenic response. The lack of mutgenic reponse to organic extracts of Paraho spent shale was …

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Alteration Of Availability Of Heavy Metals To Aquatic Microflora By Complexation With Organics Associated With Oil Shale Development, Bruce S. Mok, Jay J. Messer Jan 1983

Alteration Of Availability Of Heavy Metals To Aquatic Microflora By Complexation With Organics Associated With Oil Shale Development, Bruce S. Mok, Jay J. Messer

Reports

Leachates from both raw (unretorted) and Paraho retorted oil shale show the ability to bind copper, and perhaps cadmium, strongly enough to mitigate the inhibitory effects of these metals on the growth of the test algal,

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Understory Vegetation Inventory: An Efficient Procedure, United States Department Of Agriculture, Forest Service Jan 1983

Understory Vegetation Inventory: An Efficient Procedure, United States Department Of Agriculture, Forest Service

Forestry

The Understory Vegetation Inventory Procedure used on Forest Survey plots provides some basic information about the plant community that, when combined with other information, can be used for wildlife habitat and forage evaluation, grazing use potential, potential climax and seral stage of vegetation, and estimation of land productivity in terms of biomass.

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Production And Product Recovery For Complete Tree Utilization In The Northern Rockies, United States Department Of Agriculture, Forest Service Jan 1983

Production And Product Recovery For Complete Tree Utilization In The Northern Rockies, United States Department Of Agriculture, Forest Service

Forestry

In this study, a whole-tree harvesting system designed to produce logs and chips was evaluated on four sites, each with a different silvicultural prescription. The system consisted of: feller-bunchers, grapple-equipped rubber-tired skidders, a tree processor, a whole-tree chipper, and a hydraulic log loader. Production rates for the overall system and for its various components were developed with time-motion study techniques. Variation in productivity between study areas was analyzed with respect to stand and site characteristics.

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Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service Jan 1983

Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service

Forestry

Because of recurrent depredations by the mountain pine beetle in lodgepole pine, managers have less than a 50 percent chance of growing lodgepole pine to 16-inch diameters in most stands. This paper describes a Rate of Loss Model that estimates the amount of tree and volume loss per year and the longevity of the infestation, and shows how the model can be incorporated into forest planning. The model assumes optimum conditions for the life of an epidemic. However, actual field conditions can cause beetle populations to deviate from predictions causing a bit of overestimation, which is not considered serious in …

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