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Articles 5821 - 5850 of 7341

Full-Text Articles in Physical Sciences and Mathematics

Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad May 1981

Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During 1980-81, studies with crested wheatgrass (Agropyron desertorum) and fourwing saltbush (Atriplex canescens) were conducted in controlled environment growth chambers as well as under field conditions to achieve the following objectives:

1. To determine the effect of nitrogen fertilizer on the water use efficiency.

2. To determine the effects of various temperature, water stress and nitrogen treatments on the productivity, nitrogen content and carbohydrate reserves.

3. To determine the effects of N fertilization on fall and spring regrowth.

Crested wheatgrass and fourwing saltbush plants were maintained in three growth chambers for 60 days under three temperature …


Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman May 1981

Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaves of Rumex obtusifolius L. and R. patientia L.were exposed to combinations of mild water stress and enhanced ultraviolet-B irradiation during their ontogeny. Two UV-B treatments (enhanced UV-B and control) and three water stress treatments (-0.0 MPa, -0.2 MPa and -0.4 MPa rooting medium matric potentials) were employed. The impact of the stress interaction was assessed on the basis of changes in leaf area, average adaxial epidermal cell size, and total number of adaxial epidermal cells per leaf. Although the level of UV-B irradiation applied was insufficient to significantly alter leaf growth at any given water stress, UV-B did interact …


Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich May 1981

Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Morphology of corals of the Late Ordovician through mid-Silurian Fish Haven and Laketown Formations were analyzed to document adaptations to inferred enviromental conditions, i.e., (bathymetry, illumination, sedimentation, currents, and energy), under which their enclosing sediment was deposited. Specimens and data were collected from six sites. Insoluble-residue tests were performed on the corals' matrices.

Individual corallites of radial-lensoidal corals radiate in all directions. Vertical growth, however, was restricted in turbulent conditions. Umbrellic, radial-lensoidal corals feature downward facing corallites, considered to be an adaptation to a well illuminated environment.

On tabular lensoidal corals, constituent corallites faces exclusively upward, an orientation needed under …


Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy May 1981

Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lava flows of Tertiary-Quaternary age occur in Enoch Valley, Upper Valley, and Slug Valley in southeastern Idaho. The basalts in Upper Valley and Enoch Valley contain olivine (Fo69 to Fo37), plagioclase (An62 to An39), augite and Fe-Ti oxides. The lava in Slug Valley lacks plagioclase, but contains sanidine (Or70 to Or56) with a trace of biotite and amphibole, and thus, has been termed alkali trachyte.

Black Mountain, on the eastern side of Bear Lake, northeastern Utah, is capped by basalt. Minerals present include olivine (Fo83 to Fo72), plagioclase …


Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad May 1981

Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Arumbera Sandstone forms distinctive strike ridges with dark reddish slopes and orange-white cliffs throughout most of the northeastern Amadeus Basin. It is divisible into four readily mappable informal units. The ridge-forming units, 2 and 4, are divided into three and two subunits, respectively.

Unit 1, Subunit 2b, Unit 3 and Subunit 4b are generally comprised of recessive, pale-red to grayish-red, medium- to thin-bedded, fineto medium-grained arkose with major proportions of siltstone and mudshale. These sedimentary bodies are interpreted as a complex system of coastal to nearshore-marine environments including tidal flats, tidal channels, estuaries and beaches. Evidence includes: (1) predominance …


Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat May 1981

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …


Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza May 1981

Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to evaluate goat browsing as a means of improving these rangelands for cattle. Winter goat browsing stimulated spring twig growth from basal and axillary buds which resulted in increased production.

Twig production by heavily browsed plants (>95 percent removal of current season's twigs) was a function of precipitation, soil depth, branch location on the plant, and period of rest after browsing. As precipitation …


Mechanism Of Two Homogeneous Reactions; Co Self Exchange And N2 Self Exchange, Alan L. Rockwood May 1981

Mechanism Of Two Homogeneous Reactions; Co Self Exchange And N2 Self Exchange, Alan L. Rockwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The two atom switching reactions referred to in the title were originally studied at temperatures greater than 2000°K in shock tubes by other investigators. For each reaction they proposed a direct four-center exchange mechanism in which one of the reactant molecules must be vibrationally excited, (the vibrational excitation mechanism or VEM). One of the predictions of the VEM is that molecules which are vibrationally hot but translationally cold should react through the four center transition state that leads to exchange.

Using a mercury photosensitization technique, it is shown in the present work that excitation of CO to high vibrational levels …


Theory And Intuition, E. A. Mccullough Jr. Apr 1981

Theory And Intuition, E. A. Mccullough Jr.

Faculty Honor Lectures

Among the practitioners of science are people who are called theorists , and this lecture is concerned with the question, Just what is it that a theorist does?

If an experimentalist does experiments, then a theorist presumably does theories. What is a theory? My dictionary defines it as ". . . a system of assumptions, accepted principles, or rules of pro· cedure devised to analyze, predict or otherwise explain the nature or behavior of a specified set of phenomena."

Those who now understand perfectly what a theorist does may stop reading here because everything that follows will be superfluous. For …


Interferometer Studies Of Equatorial Fregion Irregularities And Drifts, E. Kudeki, Bela G. Fejer, D. T. Farley, H. M. Ierkic Apr 1981

Interferometer Studies Of Equatorial Fregion Irregularities And Drifts, E. Kudeki, Bela G. Fejer, D. T. Farley, H. M. Ierkic

Bela G. Fejer

A radar interferometer technique developed at Jicamarca, Peru and first used to study electrojet irregularities has now been used successfully to study plasma turbulence in the equatorial F region. Our first results have shown that the most ‘turbulent’ echoes appear to come from a region that extends for tens of kilometers in altitude but for only a kilometer or less in the east-west direction. This slab may very well be the wall of a depleted region, a plasma ‘bubble’. Sometimes the irregularities can be tracked as they move eastward or westward. Velocity profiles for the evening period obtained in this …


Radar Interferometry: A New Technique For Studyingplasma Turbulence In The Ionosphere, D. T. Farley, H. M. Ierkic, Bela G. Fejer Mar 1981

Radar Interferometry: A New Technique For Studyingplasma Turbulence In The Ionosphere, D. T. Farley, H. M. Ierkic, Bela G. Fejer

Bela G. Fejer

A new radar interferometer technique has been developed and used successfully at the Jicamarca Radio Observatory in Peru to study the strong nighttime plasma turbulence in the equatorial electrojet. The technique represents a major step forward in radar probing of turbulent irregularities such as (but not limited to) those in the electrojet. In many situations it provides far more information than previous Doppler measurements. We form the cross spectrum of the backscattered signals received from approximately overhead on two antennas, separated in this case along an east-west baseline, as well as the individual power spectra. From the phase of the …


The Frobenius Theorem, Hiroshi Nagao Jan 1981

The Frobenius Theorem, Hiroshi Nagao

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Many theorems in differential geometry which deal with the existence of certain geometrical structures or properties depend upon various existence and uniqueness theorems for differential equations. Because of its wide range of applications one of the most important of these theorems is the Frobenius Theorem for systems of total differential equations. There are four different forms of the Frobenius Theorem. In applications of the theorem one form is often preferable to the others. In this report we -shall prove the Frobenius Theorem, establish the equivalence of these various forms, and discuss a few applications.


Final Environmental Impact Statement, U.S. Department Of Housing And Urban Development Jan 1981

Final Environmental Impact Statement, U.S. Department Of Housing And Urban Development

Elusive Documents

No abstract provided.


An Intense Wave/Particle Event In The Auroral Ionosphere, A. D. Johnstone, Jan Josef Sojka, W. Gibbons, B. K. Madahar, L.J. C. Woolliscroft Jan 1981

An Intense Wave/Particle Event In The Auroral Ionosphere, A. D. Johnstone, Jan Josef Sojka, W. Gibbons, B. K. Madahar, L.J. C. Woolliscroft

All Physics Faculty Publications

An intense burst of VLF waves, at frequencies just above the local proton gyrofrequency, was observed shortly after each of two intense bursts of field‐aligned suprathermal electrons (E < 250eV) by instruments carried on a sounding rocket flown in diffuse aurora. If the two phenomena are associated with each other, the implication is that the electron acceleration occurred nearby, in a relatively small volume.


Theoretical Predictions For Ion Composition In The High-Latitude Winter F-Region For Solar Minimum And Low Magnetic Activity, Jan Josef Sojka, W. John Raitt, Robert W. Schunk Jan 1981

Theoretical Predictions For Ion Composition In The High-Latitude Winter F-Region For Solar Minimum And Low Magnetic Activity, Jan Josef Sojka, W. John Raitt, Robert W. Schunk

All Physics Faculty Publications

We combined a simple plasma convection model with an ionospheric-atmospheric density model in order to study the ion composition in the high-latitude winter F-region at solar minimum for low geomagnetic activity. Our numerical study produced time-dependent, 3-dimensional, ion density distributions for the ions NO+, O2 +, N2 +, O+, N+, and He+. We covered the high-latitude ionosphere above 54°N magnetic latitude and at altitudes between 160 and 800 km for a time period of 1 complete day. From our study we found the following (1) The ion composition exhibits a significant variation with latitude, local time, altitude, and universal time. …


Auroral Plasma Lines: A First Comparison Of Theory And Experiment, E. S. Oran, Vincent B. Wickwar, W. Kofman, A. Newman Jan 1981

Auroral Plasma Lines: A First Comparison Of Theory And Experiment, E. S. Oran, Vincent B. Wickwar, W. Kofman, A. Newman

All Physics Faculty Publications

In this preliminary report on low-energy (0.3 to 3 eV) secondary electrons in the auroral E layer (90 to 150 km), we compare intensities of plasma lines observed with the Chatanika radar to theoretical predictions obtained from a detailed numerical model. The model calculations are initiated with a flux of energetic auroral primary electrons which enter the atmosphere and lose energy to electrons, ions, and neutrals through a combination of elastic and inelastic collisions. This flux is chosen in order that the total calculated ionization rate matches one that is deduced from the radar measurements. From these same calculations the …


Evaluation Of Wastewater Filtration, Bryant L. Benth, E. Joe Middlebrooks, Dennis B. George, James H. Reynolds Jan 1981

Evaluation Of Wastewater Filtration, Bryant L. Benth, E. Joe Middlebrooks, Dennis B. George, James H. Reynolds

Reports

Tertiary filtration of secondary wastewater is frequently used to improve wastewater treatment plant effluent quality. Four experimental filter columns were operated at the Preston, Idaho, Wastewater Treatment Plant to evaluate the effectiveness of granular media, gravity filtration. The Preston plant is a trickling filter secondary treatment plant and services a population of approximately 3600 people. Four filter medium configurations were studied. Multi-media, dual-media, and single-media beds were constructed with the following media configurations: (1) coal-sand-garnet; (2) coal-sand; (3) sand-garnet; and (4) all sand. The filters were operated at two hydraulic loading rates. Effluents from the primary clarifier, trickling filter, and …


Erosion Inhibitor Performance Evaluation Under Simulated Wind And Rain, C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill Jan 1981

Erosion Inhibitor Performance Evaluation Under Simulated Wind And Rain, C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill

Reports

Introduction: Increasing public awareness of the desireability of protecting the environment from soil erosion caused by wind and water has centered attention on large construction projects such as highways and housing subdivisions, as well as on individual building sites and parking lots. If unattended, sediment produced from these areas pollutes surface water, restricts drainage, fills reservoirs, damages adjacent land, and upsets the natural ecology of lakes and streams. The search continues for products and practices that will prevent of lessen the amount of sediment leaving construction sites. Products currently in use include chemical as well as organic materials, and they …


Radar Measurements Of High-Latitude Ion Composition Between 140 And 300 Km Altitude, J. D. Kelly, Vincent B. Wickwar Jan 1981

Radar Measurements Of High-Latitude Ion Composition Between 140 And 300 Km Altitude, J. D. Kelly, Vincent B. Wickwar

All Physics Faculty Publications

The Chatanika radar has been used to measure the ratio of atomic (O+) ions to molecular (O2 +, NO+) ions in the high-latitude ionosphere. The radar results agreed well with simultaneous in situ rocket data, giving confidence in the radar method of deducing ion composition. Measurements made over long periods of time show seasonal variations, diurnal variations, and variations due to auroral processes. The transition altitude, where the number densities of atomic and molecular ions are equal, is a convenient parameter for describing the composition variation with altitude or ‘composition altitude profile.’ The transition …


Plasma Density Features Associated With Strong Convection In The Winter High-Latitude F Region, Jan Josef Sojka, W. John Raitt, Robert W. Schunk Jan 1981

Plasma Density Features Associated With Strong Convection In The Winter High-Latitude F Region, Jan Josef Sojka, W. John Raitt, Robert W. Schunk

All Physics Faculty Publications

We combined a simple plasma convection model with an ionospheric-atmospheric composition model in order to study the plasma density features associated with strong convection in the winter high-latitude F region. Our numerical study produced time-dependent, three-dimensional, ion density distributions for the ions NO+, O2 +, N2 +, O+, N+, and He+. We covered the high-latitude ionosphere above 42° N magnetic latitude and at altitudes between 160 and 800 km for a time period of one complete day. From our study, we found the following: (1) For strong convection, the electron density exhibits a significant variation with altitude, latitude, longitude, and …


Energization Of Ionospheric Ions By Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka Jan 1981

Energization Of Ionospheric Ions By Electrostatic Hydrogen Cyclotron Waves, Nagendra Singh, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

Interactions between ionospheric ions and a monochromatic electrostatic hydrogen cyclotron wave were studied numerically for conditions corresponding to the auroral plasma. Strong heating of the minority ions He+, He++, and O+ were observed. The fraction of the initial ion population which underwent heating was found to strongly depend on the mass, charge, and initial temperature of the ion species.


A Theoretical Study Of The High-Latitude Winter F Region At Solar Minimum For Low Magnetic Activity, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk Jan 1981

A Theoretical Study Of The High-Latitude Winter F Region At Solar Minimum For Low Magnetic Activity, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk

All Physics Faculty Publications

We combined a simple plasma convection model with an ionospheric-atmospheric composition model in order to study the high-latitude winter F region at solar minimum for low magnetic activity. Our numerical study produced time dependent, three-dimensional ion density distributions for the ions NO+, O2 +, N2 +, O+, N+, and He+. We covered the high-latitude ionosphere above 54°N magnetic latitude and at altitudes between 160 and 800 km for a time period of one complete day. The main result we obtained was that high-latitude ionospheric features, such as the ‘main trough,’ the ‘ionization hole,’ the ‘tongue of ionization,’ the ‘aurorally produced …


Elevated Electron Temperatures In The Auroral E Layer Measured With The Chatanika Radar, Vincent B. Wickwar, C. Lathuillere, W. Kofman, G. Lejeune Jan 1981

Elevated Electron Temperatures In The Auroral E Layer Measured With The Chatanika Radar, Vincent B. Wickwar, C. Lathuillere, W. Kofman, G. Lejeune

All Physics Faculty Publications

An extensive series of spectral measurements has been made in the auroral E region with the Chatanika incoherent scatter radar. Becasue of the small scale length for variations of electron density, temperatures, and ion-neutral collisions we used the operating mode with the best possible range resolution—9 km. About 5% of the time the data exhibited an unusual spectral shape that was most pronounced at 105 and 110 km. Instead of being almost Gaussian with only a small hint of two peaks, the spectra are much wider, with two well-developed peaks. After carefully considering the validity of the measurements and their …


Fielding Ditch Pipeline Computer Simulation Study, Calvin G. Clyde, J. Paul Tullis, Roland W. Jeppson Jan 1981

Fielding Ditch Pipeline Computer Simulation Study, Calvin G. Clyde, J. Paul Tullis, Roland W. Jeppson

Reports

The Fielding Ditch Company Pipeline is almost 3 miles long and supplies irrigation water under low pressure to adjacent fields through 33 turnouts along its length. The 24-inch non-reinforced concrete pipeline began to experience repeated structural failures soon after it was placed in operation. This study was done for the Soil Conservation Service by the Utah Water Research Laboratory to gather field data on the pipeline operating characteristics, to analyze the hydraulic transients in the pipeline with the help of a computer simulation model, and to suggest modification to protect the pipeline from future failures caused by transient pressures. Following …


Model Choice: An Operational Comparison Of Stochastic Streamflow Models For Droughts, W. Robert James, David S. Bowles, Nath T. Kottegoda Jan 1981

Model Choice: An Operational Comparison Of Stochastic Streamflow Models For Droughts, W. Robert James, David S. Bowles, Nath T. Kottegoda

Reports

The rapid development of stochastic or operational hydrology over the past 10 years has led to the need for some comparative analyses of the currently available long-term persistence models. Five annual stochastic streamflow generation models (autoregressive, autoregressive-moving-average (ARMA), ARMA-Markov, fast fractional Gaussian noise, and broken line) are compared on their ability to preserve drought-related time series properties and annual statistics. Using Monte Carlo generation procedures and comparing the average generated statistics and drought or water supply properties, a basis is established to evalute model performance on four different Utah study streams. A seasonal disaggregation model is applied to each of …


Ph Neutralization And Phosphorus Removal From A Sulfur Dioxide (So2) Treated Wastewater Using Lime (Ca(Oh)2) Addition, V. Dean Adams, Richard J. Watts Jan 1981

Ph Neutralization And Phosphorus Removal From A Sulfur Dioxide (So2) Treated Wastewater Using Lime (Ca(Oh)2) Addition, V. Dean Adams, Richard J. Watts

Reports

No abstract provided.


Design Considerations In The Use Of Glauber Salt For Energy Storage, Duane G. Chadwick, Kim H. Sherwood Jan 1981

Design Considerations In The Use Of Glauber Salt For Energy Storage, Duane G. Chadwick, Kim H. Sherwood

Reports

Various design concepts for the utilization of the latent heat of Glauber salt at temperatues between 25 degrees C and 50 degrees C were studied. Consideration was given to system economics and what particular heat storage system if perfected would be most cost effective. The problems of limited crystal size and heat transfer into and out of salt crystals is discussed. Crystal size is affected by the degree of agitation the salt solution experiences during the salt cooling process. Consequently, crystal size was moderated in a favorable way by introducing air bubbles at the bottom of the salt container. As …


Natural Salinity Removal Processes In Reservoirs, Jay J. Messer, Eugene K. Israelsen, V. Dean Adams Jan 1981

Natural Salinity Removal Processes In Reservoirs, Jay J. Messer, Eugene K. Israelsen, V. Dean Adams

Reports

A small but significant amount of salinity removal has been reported by various authors to occur in mainstem Colorado River reservoirs. Recalculation of some of these salinity budgets, together with a review of the data bases used, usggests taht removal has not often been conclusively demonstrated. Laboratory microcosm experiments and field data indicate that calcium carbonate precipitation, perhaps with some coprecipitation of magnesium carbonate, is the mechanism responsible for most of the salinity removal in Oneida Reservoir, Idaho. Coprecipitation processes (including ion exchange), coagulation, and bioassimilation do not appear to be important natural salinity removal mechanisms. Finally, loss of calcium, …


Water Quality In Pleasant Valley, Utah, Calvin G. Clyde, Dennis B. George, Kun Mo Lee, Phil Pucel, William Hay Jan 1981

Water Quality In Pleasant Valley, Utah, Calvin G. Clyde, Dennis B. George, Kun Mo Lee, Phil Pucel, William Hay

Reports

Pollution of shallow groundwater due to wastewater disposal in Pleasant Valley, Utah, was investigated from October 1979 through August 1980. Water samples were collected from 23 wells and 5 stream sampling sites. Water quality analysis revealed pollution at several sites. Groundwater pollution caused by man’s activities in the area was observed in Bolotas and Scofield Campsite subdivisions. Severe shallow groundwater pollution measured in wells which were located in south and north profiles of the town of Scofield, Utah, could have originated from the municipal waste disposal practice in the town. Natural phenomena, however, such as pyrite oxidation, could possible have …


Evaluation Of Particular Mulches For Fostering Plant Growth And Inhibiting Erosion (Phase 2), C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill Jan 1981

Evaluation Of Particular Mulches For Fostering Plant Growth And Inhibiting Erosion (Phase 2), C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill

Reports

Introduction: Increasing public awareness of the desireability of protecting the environment from soil erosion caused by wnid and water has centered attention on large construction projects such as highways and housing subdivisions, as well as on individual building sites and parking lots. If unattended, sediment produced from these areas pollutes surface water, restricts drainage, fills reservoirs, damages adjacent land, and upsets the natural ecology of lakes and streams. The search continues for products and practices that will prevent or lessen the amount of sediment leaving construction sites. Products currently in use include chamical as well as organic materials, and they …