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Demographic And Bioenergetic Studies Of Cutworms In Curlew Valley, W. J. Hanson, G. F. Knowlton Jan 1973

Demographic And Bioenergetic Studies Of Cutworms In Curlew Valley, W. J. Hanson, G. F. Knowlton

Memorandum

No abstract provided.


Gaseous Losses Of Nitrogen From The Soil Of Semi-Arid Regions, T. C. Tucker, R. L. Westernman Jan 1973

Gaseous Losses Of Nitrogen From The Soil Of Semi-Arid Regions, T. C. Tucker, R. L. Westernman

Memorandum

No abstract provided.


Respiratory Metabolism Of Utah Chub (Gila Atraria), R. H. Kramer, P. K. Rajagopal Jan 1973

Respiratory Metabolism Of Utah Chub (Gila Atraria), R. H. Kramer, P. K. Rajagopal

Memorandum

No abstract provided.


Water Uptake By Plants Under Desert Conditions, H. K. Qashu, D. D. Evans, M. L. Wheeler, Theodore Sammis Jan 1973

Water Uptake By Plants Under Desert Conditions, H. K. Qashu, D. D. Evans, M. L. Wheeler, Theodore Sammis

Memorandum

No abstract provided.


Curlew Valley Validation Site Report, David F. Balph Jan 1973

Curlew Valley Validation Site Report, David F. Balph

Memorandum

No abstract provided.


Distillation-Condensation Of Water And Nutrient Movement In A Desert Ecosystem, N. Stark Jan 1973

Distillation-Condensation Of Water And Nutrient Movement In A Desert Ecosystem, N. Stark

Memorandum

No abstract provided.


Terrestrial Models: Introduction And Main Programs, D. W. Goodall, C. Gist Jan 1973

Terrestrial Models: Introduction And Main Programs, D. W. Goodall, C. Gist

Memorandum

No abstract provided.


Terrestrial Models: Plant Processes (Version I, Ii, Iii), W. Valentine Jan 1973

Terrestrial Models: Plant Processes (Version I, Ii, Iii), W. Valentine

Memorandum

No abstract provided.


Terrestrial Models: Animal Processes (Versions I, Ii), S. Payne Jan 1973

Terrestrial Models: Animal Processes (Versions I, Ii), S. Payne

Memorandum

No abstract provided.


Sensitivity Analysis, I. Noy-Meir, D. Goodall Jan 1973

Sensitivity Analysis, I. Noy-Meir, D. Goodall

Memorandum

No abstract provided.


Aquatic Models, Wayne Minshall Jan 1973

Aquatic Models, Wayne Minshall

Memorandum

No abstract provided.


Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, Peter L. Comanor Jan 1973

Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, Peter L. Comanor

Memorandum

No abstract provided.


Measurements Of Carbon And Nitrogen Changes In Soil, Eugene E. Staffeldt, Kristina Bemond Vogt Jan 1973

Measurements Of Carbon And Nitrogen Changes In Soil, Eugene E. Staffeldt, Kristina Bemond Vogt

Memorandum

No abstract provided.


Prediction Of Plant-, Soil- And Air-Temperature On A Microscale In The Desert, Inge Dirmhirn, Frank Eaton Jan 1973

Prediction Of Plant-, Soil- And Air-Temperature On A Microscale In The Desert, Inge Dirmhirn, Frank Eaton

Memorandum

No abstract provided.


Diest, Food Preference And Reproductive Cycles Of Some Desert Rodents, Russell P. Balda, Clark E. Franz, O.J. Reichman, Kent M. Van De Graaff Jan 1973

Diest, Food Preference And Reproductive Cycles Of Some Desert Rodents, Russell P. Balda, Clark E. Franz, O.J. Reichman, Kent M. Van De Graaff

Memorandum

No abstract provided.


Consumption, Utilization And Modification Of Nutritional Resources By The Jackrabbit (Lepus Californicus) In The Mohave Desert, V.H. Shoemaker, K.A. Nagy, W.R. Costa Jan 1973

Consumption, Utilization And Modification Of Nutritional Resources By The Jackrabbit (Lepus Californicus) In The Mohave Desert, V.H. Shoemaker, K.A. Nagy, W.R. Costa

Memorandum

No abstract provided.


Chronic Toxicity Of A Copper, Cadmium And Zinc Mixture To The Fathead Minnow (Pimephales Promelas Rafinesque), John G. Eaton Jan 1973

Chronic Toxicity Of A Copper, Cadmium And Zinc Mixture To The Fathead Minnow (Pimephales Promelas Rafinesque), John G. Eaton

United States Environmental Protection Agency: Publications

Fathead minnows were exposed to a series or concentrations of a copper, cadmium and zinc mixture during a 12.5 month chronic test in water of 200 mg 1-1 total hardness. The metal concentrations in the mixture were selected on the basis of results obtained during previous chronic exposures to each of the metals individually in the same water. Strict summation of the chronic toxicities of the metals was not indicated when they were tested in combination. Toxic effects of the mixture attributable to copper appeared to be increased, but that attributable to cadmium was reduced. The effects thought to …


Captan Toxicity To Fathead Minnows (Pimephales Promelas), Bluegills (Lepomis Macrochirus), And Brook Trout (Salvelinus Fontinalis), Roger O. Hermanutz, Leonard H. Mueller, Kenneth D. Kempfert Jan 1973

Captan Toxicity To Fathead Minnows (Pimephales Promelas), Bluegills (Lepomis Macrochirus), And Brook Trout (Salvelinus Fontinalis), Roger O. Hermanutz, Leonard H. Mueller, Kenneth D. Kempfert

United States Environmental Protection Agency: Publications

The toxic effects of capt an on survival, growth, and reproduction of fathead minnows (Pimephales promelas) and on survival of bluegiIIs (Lepomis macrochirus) and brook trout (Salvelinus fontinalis) were determined in a flow-through system. In a 45-week exposure of fathead minnows, survival and growth were adversely affected at 39.5 μLg/Iiter. Adverse effects on spawning were suspected but not statisticaIly demonstrated at 39.5 and 16.5 μLg/Iiter. The maximum acceptable toxicant concentration (MATC), based on survival and growth, lies between 39.5 and 16.5 μLg/liter. The lethal threshold concentration (LTC) derived from acute exposures was 64 μLg/liter, …


Chronic Effect Of Low Ph On Fathead Minnow Survival, Growth And Reproduction, Donald I. Mount Jan 1973

Chronic Effect Of Low Ph On Fathead Minnow Survival, Growth And Reproduction, Donald I. Mount

United States Environmental Protection Agency: Publications

Fathead minnows (Pimephales promelas Rafinesque) were continuously exposed to reduced pH levels of 4.5, 5.2, 5.9, 6.6 and 7.5 (control) during a 13-month, one-generation test. Survival was not affected, even at the lowest pH tested. Fish behavior was abnormal, and fish were deformed at pH 4.5 and 5.2. Egg production and egg hatchability were reduced at pH 5.9 and lower, and all eggs were abnormal. A pH of 6.6 was marginal for vital life functions, but safe for continuous exposure. Free carbon dioxide, liberated by the addition of sulfuric acid to reduce the pH, may have had an unknown …


Preliminary Interpretations Of Coyote Population Mechanics With Some Management Implications, Frederick F. Knowlton Jan 1973

Preliminary Interpretations Of Coyote Population Mechanics With Some Management Implications, Frederick F. Knowlton

Great Plains Wildlife Damage Control Workshop Proceedings

The need for control of coyote (Canis latrans) depredations and a simultaneous demand for recognition of the aesthetic and ecologic values of the species create a conflict in resource utilization that should be resolved through more intensive management. A coyote population model is proposed from current estimates of density, reproduction, population structure, and mobility. Densities of 0.5 to 1.0 coyote per square mile are frequently suggested, with occasional estimates of 4.0 or more per square mile. Reproductive rates fluctuate as functions of the proportion of females that ovulate, the average number of ova shed, and in utero viabilities. …


Solving Three-Dimensional Potential Flow Problems By Means Of An Inverse Formulation And Finite Differences, Allen L. Davis, Roland W. Jeppson Jan 1973

Solving Three-Dimensional Potential Flow Problems By Means Of An Inverse Formulation And Finite Differences, Allen L. Davis, Roland W. Jeppson

Reports

A finite difference method is developed to solve the three-dimensional, steady, incompressible, potential flow equations obtained by using a potential function, o, and two mutually orthogonal stream functions, u and u*, to describe the flow. Problems are formulated in an inverse space where the potential function and the two stream functions are the independent variables, and the Cartesian coordinates x, y, and z are the dependent variables. The boundaries of the problem in the physical space, including the free surface, have known positions in the inverse space, so trial and error adjustments to the positions of the boundaries are unnecessary. …


Irrigation And Non-Irrigation Alternatives For Reducing Sugar Cane Transportation Costs In Santa Cruz, Bolivia, E. Boyd Wennergren, Allen D. Lebaron, Lee Bailey, Morris D. Whitaker Jan 1973

Irrigation And Non-Irrigation Alternatives For Reducing Sugar Cane Transportation Costs In Santa Cruz, Bolivia, E. Boyd Wennergren, Allen D. Lebaron, Lee Bailey, Morris D. Whitaker

Reports

No abstract provided.


Effect Of Increased Water Supply On Net Returns To Dairy Farms In Sonsonate, El Salvador, Morris Whitaker, Gary Glenn, Allen Lebaron, Boyd Wennergren Jan 1973

Effect Of Increased Water Supply On Net Returns To Dairy Farms In Sonsonate, El Salvador, Morris Whitaker, Gary Glenn, Allen Lebaron, Boyd Wennergren

Reports

No abstract provided.


A Water Resource Management Model, Upper Jordan River Drainage, Utah, Bi-Huei Wang, James I. Felix, Rick L. Gold, Craig T. Jones, J. Paul Riley Jan 1973

A Water Resource Management Model, Upper Jordan River Drainage, Utah, Bi-Huei Wang, James I. Felix, Rick L. Gold, Craig T. Jones, J. Paul Riley

Reports

As demands upon available water supplies increase within a river basin, there is an accompanying increase in the need to assess the downstream consequences resulting from changes at specific locations within the hydrologic system. This problem is approached in this study by digital computer simulation of the hydrologic system. Modeling concepts are based upon basic relationships which describe the various hydrologic processes. Within a hydrologic system these relationships are linked by the continuity-of-mass principle which requires a mass balance at all points. Spatial resolution is achieved by considering the modeled area as a series of subbasins. The time increment adopted …


Modification Of A Continuous Ice Crystal Replicator, Paul D. Thornley Jan 1973

Modification Of A Continuous Ice Crystal Replicator, Paul D. Thornley

Reports

A continuous ice-crystal replicator was modified by the addition of a gear drive to the cating wheel. This modification utilizes a positive drive force on the coating wheel rather than the friction force between the coating wheel and the film. The coating wheel operates successfully for at least 12 hours without slippage or damage to the film. Studies have uncovered several deficiencies in the replicator design which could be corrected. The correction of these deficiencies would lead to an improved quality of ice-crystal replicas. The need for continued studies in the fluid properties of Formvar solution is pointed out. Information …


A Streamflow Simulation Model For A Semi-Arid Region, Adnan A. Saad, L. Douglas James Jan 1973

A Streamflow Simulation Model For A Semi-Arid Region, Adnan A. Saad, L. Douglas James

Reports

A streamflow simulation model which would reproduce the essential feature of the hydrologic regime of a semi-arid region, in this case Jordan, was developmed and described. The model is intended to fit conditions which exist in such a region. The hydrologic processes components which represent the evaporation and the base flow distinguish the Jordan model from others. Development of each function of the model and its constants was based on all the minimal amount of data available. one year of data was used to calibrate the model for Wadi Zerqa watershed. The model was then applied to simualte four years …


Hydraulic Tests On Model Of Manifold Of The Pumps Of The 1974 Extension Of The Yorktown Power Station With All Combinations Of One And Two Branches Taken Out Of Operation, Roland W. Jeppson, Calvin G. Clyde, Charles Kincaid Jan 1973

Hydraulic Tests On Model Of Manifold Of The Pumps Of The 1974 Extension Of The Yorktown Power Station With All Combinations Of One And Two Branches Taken Out Of Operation, Roland W. Jeppson, Calvin G. Clyde, Charles Kincaid

Reports

Introduction: A description of the fabrication of the manifold model and the design of the facilities constructed to test the model under various steady state flow conditions is given in the previous report. All tests included in the last report were with equal flows occurring in each of the five branches. Since the operation of the prototype manifold will necessitate that one, and possibly two pumps, be taken out of operations when the demand for cooling water is at a minimum, Browth & Root, Inc. requested taht the performance of the manifold model be determined under steady-state conditions with: (1) …


Head Losses Due To Ring-Tite Filament Wound Elbows And Tees And Frictional Losses In Pipes Of Polyvinylchloride, Roland W. Jeppson Jan 1973

Head Losses Due To Ring-Tite Filament Wound Elbows And Tees And Frictional Losses In Pipes Of Polyvinylchloride, Roland W. Jeppson

Reports

This study consists of collecting and analyzing experimental data to determine the Darcy-Weisbach friction factor for 6-inch and 4-inch PERMASTRAN® pipes and the head losses due to RING-TITE filament-wound 6-inch 90° elbows, a 6 x 6-inch tee under several modes of operation, and a 6 x 6 x 4-inch tee with the flow entering a 6-inch branch and leaving through the 4-inch branch. The test program consisted of 8 series of individual tests with each series giving data for flow rates for each series ranging from 150 gpm to either 1200 gpm or 1500 gpm depending upon the series. The …


Computer Simulation Of The Hydrologic And Salinity Flow Systems Within The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, J. Paul Riley Jan 1973

Computer Simulation Of The Hydrologic And Salinity Flow Systems Within The Bear River Basin, Robert W. Hill, Eugene K. Israelsen, J. Paul Riley

Reports

Accompanying the increased use of water resources is an increases accumulation of chemical pollutants. Te prevent degradation of the water resources beyong useful limits, pollution inputs from additional uses must be quite accurately predicted prior to implementation of the new use. The model described in this report was formulated to provide the required predictive capability for the Bear River Basin. Modeling concepts of the hydrologic system are based upon the development of basin relationships describing the hydrologic processes which are linked together by the countinuity-of-mass principle. The salinity flow system is then linked to the hydrologic system based on the …


Hydrologic Inventory Of The Bear River Study Unit, Frank W. Haws Jan 1973

Hydrologic Inventory Of The Bear River Study Unit, Frank W. Haws

Reports

Purpose and Scope of Study.

The 1963 Utah State Legislature authorized the Utah Water and Power Board (now the Utah Division of Water Resources) to develop a state water plan in order to give coordination and direction to the activities of all state and federal agencies concerned with Utah's water resources. To facilitate the development of this plan, a proposal was submitted through the State Planning Coordinator in the Governor's Office to the Urban Renewal Administration of the Housing and Home Finance Agency. Funding was approved effective May 19, 1966, under the Urban Planning Assistance Program authorized by Section 701 …