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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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Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service Jan 1983

Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service

Forestry

The objective of this paper is to briefly review winter injury of plants and shrubs in particular, document the observed winter injury of 1976-77, and correlate the occurrence with weather records.

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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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Llaffs - A Lightning-Locating And Fire-Forecasting System, United States Department Of Agriculture, Forest Service Jan 1983

Llaffs - A Lightning-Locating And Fire-Forecasting System, United States Department Of Agriculture, Forest Service

Forestry

This publication contains programs and documentation to implement an algorithm for calculating lightning fire probability. This calculation is based on a model originally developed for the National Fire-Danger Rating System. The model algorithm estimates the probability that a lightning discharge from cloud to ground will ignite a fire in fuels at the ground terminus of the lightning. Probability is estimated using variables that are measures of the fuel state and type, rain, and lightning. Details of the model can be found in Fuquay and others (1979), Latham (1979), and Fuquay (1980).

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Salvage And Thinning Operations In Second-Growth Ponderosa Pine Stands, United States Department Of Agriculture, Forest Service Jan 1983

Salvage And Thinning Operations In Second-Growth Ponderosa Pine Stands, United States Department Of Agriculture, Forest Service

Forestry

This report describes and discusses a harvesting system made up of commercially available equipment and modified farm tractors that has been successfully used to salvage and thin second-growth ponderosa pine stands. Commercial equipment consisted of fellerbunchers, a skidder, and a chipper. Farm tractors were equipped with grapples and metal reinforcings to adapt them to forest use.

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Planning For Rural Human Services: The Western Energy-Impact Experience, United States Department Of Health And Human Services, Office Of Human Development Services Jan 1983

Planning For Rural Human Services: The Western Energy-Impact Experience, United States Department Of Health And Human Services, Office Of Human Development Services

Fuel Sources

Beginning in the mid-1970's, the development of energy resources in the western United States created significant changes in the small, rural communities of this area. Many of the changes were the result of the rapid influx of population associated with industrial activities. It has long been recognized that communities subject to rapid growth have difficulty meeting the physical facility needs of their residents, such as housing, shopping and school facilities, and sewer and water services. In recent years, a growing recognition of the importance of the social effects of rapid community growth has also developed. These effects include the deterioration …

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Measuring Species Diversity On Revegetated Surface Mines: An Evaluation Of Techniques, United States Department Of Agriculture, Forest Service Jan 1983

Measuring Species Diversity On Revegetated Surface Mines: An Evaluation Of Techniques, United States Department Of Agriculture, Forest Service

Mines and Mineral Resources

This report reviews the three most commonly used techniques for measuring species diversity in plant communities: (1) diversity indices, (2) rank correlation tests, and (3) similarity indices. The author discusses the suitability of each technique for assessing species diversity on mined land and evaluates the most often used indices, test statistics, or coefficients of each technique. Applications of the Shannon-Weiner diversity index, Spearman's rank order correlation coefficient, Motyka and others' and Bray and Curtis' version of Sorensen's similarity index, and Spatz' version of Jaccard's index for assessing mined land species diversity are presented in the appendix.

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Fireline Production: A Conceptual Model, United States Department Of Agriculture, Forest Service Jan 1983

Fireline Production: A Conceptual Model, United States Department Of Agriculture, Forest Service

Wildfires

This report describes a conceptual model that provides a framework for the components of fireline production. Other conceptual or operational fire-related models may be linked with this production model. Major components and relationships are diagramed.

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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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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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The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell Jan 1983

The Effects Of Ultraviolet-B Radiation On Plant Competition In Terrestrial Ecosystems, Warren G. Gold, Martyn M. Caldwell

Green Canyon Environmental Research Area, Logan Utah

Evidence regarding the interaction of ultraviolet-B radiation and plant competition in terrestrial ecosystems is examined. The competitive interactions of some species pairs were affected even by ambient solar UV-B radiation when compared to control pairs grown without UV-B. Also, the total shoot biomass of these species pairs was depressed under ambient UV-B. Relatively large increases in UV-B radiation altered the competitive interactions of some species pairs grown in pots under field conditions, but did not affect the total shoot biomass production of those pairs. Recent field experiments have examined the competitive interactions of wheat and wild oat under a simulated …

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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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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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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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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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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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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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Successional Trends In An Ungrazed, Arid Grassland Over A Decade, Edgar F. Kleiner Jan 1983

Successional Trends In An Ungrazed, Arid Grassland Over A Decade, Edgar F. Kleiner

Canyonlands Research Bibliography

A study has been made of the vegetational condition of a formerly grazed area, Chesler Park, in Canyonlands National Park. A comparison was made with the same area 10 years earlier. The 10-year successional changes are also compared to baseline data of 10 years earlier from Virginia Park, an adjacent ungrazed area. Because of inaccessibility and long isolation from disturbances, Virginia Park is presumed to be in climax condition and is the control for this study. Chesler Park shows a successional trend after 10 years toward the vegetational condition of Virginia Park. This is exemplified, with only one major exception …

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Image Analysis Of Morphological Changes In Wiener Batters During Chopping And Cooking, A. G. Kempton, S. Trupp Jan 1983

Image Analysis Of Morphological Changes In Wiener Batters During Chopping And Cooking, A. G. Kempton, S. Trupp

Food Structure

Histological changes in wiener batters during chopping and cooking have often been illustrated with "representative" fields . The practice of selecting representative fields ignores variation and leads to word descriptions that cannot be correlated with numerical scores for functional or sensory tests . If wieners are regarded as a multi-component system, objectivity can be achieved by selecting many fields for each sample according to a rigid sampling plan. Image analysis quantified parameters of both the fat and protein components . The reduction in size of fat globules during chopping of a commercial formulation, for example, was a function of area …

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Reconnaissance Of Sediment-Phosphorus Relationships In Upper Flaming Gorge Reservoir, Jay J. Messer, Jean M. Ihnat, Bruce Mok, David Wegner Jan 1983

Reconnaissance Of Sediment-Phosphorus Relationships In Upper Flaming Gorge Reservoir, Jay J. Messer, Jean M. Ihnat, Bruce Mok, David Wegner

Reports

Executive Summary: A reconnaissance-level study was conducted in Flaming Gorge Reservoir, Wyoming, during the late summer of 1982 in order to determine the possible importance of the sediment sin exacerbating the blue-green algal blooms that occur in summer in the upper reservoir. Sediments can affect phytoplankton dynamics in reservoirs on an annual basis by delyaing the availability of particulate P associated with spring runoff until late summery, when the warm water temperatures and the light climate favor the growth of blue-green algae. Over the longer term, however, sediments that historically have served as a trap for part of the annual …

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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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Bioassays- Procedures And Results, A. F. Maciorowski, L. W. Little, L. F. Raynor, Ronald C. Sims, J. L. Sims Jan 1983

Bioassays- Procedures And Results, A. F. Maciorowski, L. W. Little, L. F. Raynor, Ronald C. Sims, J. L. Sims

Biological Engineering Faculty Publications

Bioassay procedures to describe, evaluate, and predict the potential hazard of toxic materials to organisms and ecosystems, and the health-related aspects of polluted waters continue to receive widespread attention. Symposium proceedings and books pertinent to toxic substances management and test procedures have appeared, as have several literature reviews pertinent to specific pollutants. The proceedings of the fifth annual ASTM symposium on aquatic toxicology presented a collection of papers directed to research needs in aquatic toxicology and hazard assessment, new concepts in aquatic toxicology, biological availability and sediment toxicity, and hazard assessment and water quality criteria.1 A state-of-the-art overview pertinent …

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An Experimental Investigation Of The Effects Of Crude Oil On Two Freshwater Lake Ecosystems, Martin D. Werner, V. Dean Adams, Vincent A. Lamarra Jan 1983

An Experimental Investigation Of The Effects Of Crude Oil On Two Freshwater Lake Ecosystems, Martin D. Werner, V. Dean Adams, Vincent A. Lamarra

Reports

Responses of two freshwater lake ecosystems of the Intermountain West to crude oil impaction were investigated. The research was conducted in two phases; in the first phase effects of crude oil were studied on an ecosystem established in three phase laboratory microcosms (gaseous-aqueous-sediment), which simulated the natural lakes. Notable responses of the microcosm ecosystem to oil impaction included: an increased oxygen demand by the biological community, nutrient immobilization, a reduction in plant biomass accumulation and a heterotrophically dominated ecosystem. The increased availability of biologically degradable reduced carbon (i.e., the oil) and nutrient immobilization, rather than toxic effects of oil on …

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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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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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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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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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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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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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