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Full-Text Articles in Physical Sciences and Mathematics

Introduction And Enhancement Of Vegetative Cover At Lake Mead, Jennifer S. Haley, Lisa K. Croft, Suzanne E. Leavitt, Larry J. Paulson Dec 1989

Introduction And Enhancement Of Vegetative Cover At Lake Mead, Jennifer S. Haley, Lisa K. Croft, Suzanne E. Leavitt, Larry J. Paulson

Publications (WR)

Studies done by the Nevada Department of Wildlife (NDOW) and the Arizona Fish and Game between 1978 and 1981 indicate that inadequate cover may be limiting the production and survival of largemouth bass at the Lake Mead National Recreation Area (LMNRA). As a result of these studies, NDOW initiated a contract in 1986 with the Lake Mead Research Center (LMRC) to investigate means of improving habitat for game fish by introducing natural and/or artificial cover.

During Phase I (1986-1987) of this contract, the shoreline of Lake Mead was surveyed for aquatic and terrestrial plant growth. Also during this time, submerged …


Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott Jun 1989

Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott

Technical Reports

A PC/AT computer model was developed to simulate the transport of water, nitrate and ammonia in the soil profile after an application of poultry litter to pasture. The model was written using FORTRAN 77 compiler and can be used on any IBM type compatible computer with a math coprocessor. Poultry litter has been shown to be a potential source of plant nutrients, but mismanagement can result in nitrate pollution of the surface and groundwater. The model is composed of a main program, 11 subroutines and three subprograms. An example was shown of the flexibility and dynamic nature of the computer …


Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice Jun 1989

Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice

Technical Reports

Occurrences of pesticides in our nations ground water are on the rise. As states become aware of this problem and begin monitoring programs, incidence of contamination will probably increase. Since the problem of pesticides in groundwater is relatively new, little research has centered on the fate of pesticides after they reach the groundwater environment. In Northwest Arkansas efforts to monitor groundwater for pesticides have been small. Twenty-five springs in Northwest Arkansas were sampled in the fall of 1988, and spring of 1989. Analysis for atrazine, alachlor, metolachlor, diuron, and simazine in spring water was preformed using gas liquid chromatography and …


An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker Jun 1989

An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker

Technical Reports

A diagnostic expert system for an activated sludge wastewater treatment plant has been designed to link with a relational database management system for obtaining operational parameter values that are used by the program to diagnose operational problems that may occur in the process. The problems that are dealt with by the system are bulking sludge, floating sludge, defloculation, ashing, solids washout, foaming problems, high soluble effluent BOD and problems in the aeration system. The link between the expert system and the database is accomplished via programming that is initiated by the expert system program. The operator of the system is …


Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer Jun 1989

Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer

Technical Reports

A data base of the algae of Arkansas ecoregions has been established to describe the numerous taxa that occur within the aquatic ecosystems included in these regions. The organisms were identified with the aid of diverse literature from throughout the world. These sources are written in multiple languages and the living organisms had to be compared with outline or silhouette drawings. These illustrations may include shading, but none present the true color of the organism but only the characteristics of the descriptive source. Primary characteristics used to identify algae is based upon pigmentation of the plastid and the number and …


Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis Jun 1989

Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis

Technical Reports

Cotton (Gossypium hirsutum L) is an important crop in the southern United States. The crop is grown in both irrigated and rainfed situations and is seldom free from periods of water shortages at some stage during the season. In recent years the need for consistency in yields and a stable cash flow has resulted in a rapid expansion in the number of irrigated acres of cotton in the Mississippi Delta. Irrigation research has, however, not kept pace with this expansion. This project represents a start at meeting this urgent need. The influence of weather patterns necessitates that these studies be …


Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle Jun 1989

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …


Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice Jun 1989

Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice

Technical Reports

An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in …


Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab Jun 1989

Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab

Technical Reports

There are several agencies within the state of Arkansas dealing with underground water. Each agency has its own database that acts as an isolated depository of data. Practically, the communication among these databases is zero, not because there is no need for it, but because the communication is very difficult if not impossible. Data redundancy, inconsistency, and lack of integrity is overwhelming. In this study we have addressed the problem of lack of unity among the databases belonging to different agencies. Also, as an alternative we have developed a relational database. In this database the data was normalized to 4NF. …


Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection May 1989

Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection

Publications (WR)

In September 1987 the Nevada Division of Environmental Protection revised Water Quality Standards for Las Vegas Wash (LVW) and Lake Mead. Standards were set for chlorophyll-a and unionized ammonia in Las Vegas Bay (LVB) (NDEP 1987). The 1986 and 1987 LVB data showed non-achievement of both the chlorophyll-a and unionized ammonia standard which triggered an analysis of total phosphorus and total ammonia Total Maximum Daily Loads and Waste Load Allocations which are presented in this report.

This report is separated into three sections:

1. 1987 Las Vegas Bay Water Quality Conditions and Seasonal Periodicity.

2. Concentration Estimates at Northshore Road …


Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection Apr 1989

Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1988. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading and increased ammonia in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.


Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife Mar 1989

Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife

Publications (WR)

Red swamp crayfish (Procambarus clarkii) were trapped in Flamingo Wash, an urban wash of Las Vegas, during four periods of 1988. Life history and reproductive success were determined. The trapped crayfish were marked and released into a study cove in Lake Mead as part of an experimental stocking program. Retrap data from the study cove were used to determine life history, habitat preferences, and movement patterns of the stocked crayfish. In addition, a literature search was done on red swamp crayfish ecology, including food preferences, life history, habitat preferences and fish predation.


Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore Jan 1989

Determination Of The Suitability Of Arkansas River Water For Municipal, Industrial And Agricultural Use, James W. Moore

Technical Reports

River water samples from the five sites were collected by the U. S. Geological Survey (USGS) in accordance with their established sampling procedures. Samples for wet chemistry and atomic absorption analyses were delivered to the Bell Engineering Center at the University of Arkansas by USGS personnel. Samples for organics analyses from the Lee Creek, Dardanelle, Little Rock and Pine Bluff sites were delivered by USGS to American Interplex in Little Rock. Samples for organics analyses for the Van Buren site were delivered to the Bell Engineering Center and sent by United Parcel Service (next day air) to Daily Analytical Services …


Factors Affecting Lupin Crop Establishment In The Northern Agricultural Region Of Western Australia., K W. Mccarthy, A M. Doswell, R J. Delane, M W. Sweetingham Jan 1989

Factors Affecting Lupin Crop Establishment In The Northern Agricultural Region Of Western Australia., K W. Mccarthy, A M. Doswell, R J. Delane, M W. Sweetingham

Experimental Summaries - Plant Research

Lupin establishment, 89EC6. The effect of machine, depth of sowing, seed soil contact and herbicide incorporation on lupin establishment, 89GE8. The effect of phosphate application on lupin establishment, 89GE99. The effect of seeding technique, depth of sowing, seed soil contact and fungicide on lupin establishment on course sands, 89GE9. Integrated control strategy of Rhizoctonia hypocotyl root rot of lupins, 89GE11, 89GE12, 89GE12B, 89GE13, 89GE14. Strategies for lupin patch control, 89EC7 and 89GE15. The effect of seed size and sowing rate on lupin establishment, 89C1, 89GE6, 89GE7, 89EC5, 89BA34, 89TS49, 89GE10, 89EC4, 89GE4,


Systems For Early Sowing Of Wheat In Low Rainfall Zones., N J. Kerr Jan 1989

Systems For Early Sowing Of Wheat In Low Rainfall Zones., N J. Kerr

Experimental Summaries - Plant Research

Background and early significance. Effect of sowing date and nitrogen fertilizer on wheat varieties in low rainfall areas, 89GE76, 89GE77, 89NM1, 89GE78, 89NM2, 89NM3, 89GE78. Tillage and sowing methods for early sowing of wheat in low rainfall areas, 89GE79. Aims, Background, Experimental details.


Pasture Agronomy., C. K. Revell Jan 1989

Pasture Agronomy., C. K. Revell

Experimental Summaries - Plant Research

Trial 89ME82

a. Medic establishment.

Establishing burr medic pastures with cereal cover.
Merredin

Trial 89SC19

b. Serradella - Potash response.

Response of serradella to potash fertilizer.
South Carrabin

Trial 89M44

c. Serradella/Grass competition

Effect of grass competition on production of serradella.
Merredin Research Station.

Trial 89SC HERB

d. Herbicide tolerance of Serradella.

Herbicide tolerance of Madeira serradella.
South Carrabin


Medic Variety Evaluation., C. K. Revell Jan 1989

Medic Variety Evaluation., C. K. Revell

Experimental Summaries - Plant Research

Trial 89M57

Medic variety evaluation - rows.
Merredin Research Station (Paddock T5)

Trial 89ME71

Selection of early maturing M. murex.
Nokaning.

Trial 88ME86

Evaluation of Santiago in low rainfall areas.
Mukinbudin.

Trial 87M73

Medic variety evaluation - large plots.
Merredin Research Station.

Trial 86M65

M. polymorpha variety evaluation - large plots.
Merredin Research Station.

Trial 88ME84

Evaluation of burr medics on Morrel soils.
Nokaning.

Trial 88SC30

Selection of early maturing M. murex.
Merredin.


The Grazing Value Of Medicago Murex., C. M. Saunders Jan 1989

The Grazing Value Of Medicago Murex., C. M. Saunders

Experimental Summaries - Plant Research

Trial 88KA92

Location: Potts Road, East Kojonup.

At present, limited information is available on the grazing value of Medicago murex cv. Zodiac on sheep live weights and wool growth. This trial was designed to provide data on the relative performance of sheep grazing Zodiac compared with the recommended subterranean clovers (Junee/Seaton Park) in the > 450mm rainfall zone in WA.


Legume Species Mixtures., C. M. Saunders Jan 1989

Legume Species Mixtures., C. M. Saunders

Experimental Summaries - Plant Research

Trial 86KA64 - ironstone hardsetting clay pH 8.0
86KA65 - orange/red loam pH 7.0
86KA66 - sandy gravel pH 5.6 - 5.7

Location: Dumbleyung.

Current recommendations for pasture species in the medium rainfall zone has not included species mixtures for paddocks with varying soil types. These trials (three in total) are designed to test the hypothesis that legume species mixtures are more productive and persistent in the long term than monocultures, across three soil types and three different cropping/pasture rotations (continuous pasture, 1 year pasture : 1 year crop rotation, 2 years pasture : 1 year crop rotation).


Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt Jan 1989

Cultivar Evaluation On Low Rainfall Heavy Textured Soils., Bradley Nutt

Experimental Summaries - Plant Research

a. Trial 88GE34

Cultivar evaluation in machine sown plots.
Location: NMRS

The higher seed yield of Serena compared to the other cultivars resulted in better early forage .production as well a legume dominated pasture.

b. Trial 88TS 63 and 88TS 65

Wheat yields following pastures.
Location: 88TS63 - Perenjori and 88TS65 - Three Springs.

There was no response to nitrogen in either biological yield or grain yield of wheat sown over volunteer based pasture at the Three Springs site. All pasture treatments resulted in similar wheat yields except for Sava because of poor control of the snail medic under the …


Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt Jan 1989

Tactical Nitrogen Decisions For Wheat (And N Rates Trials), J. W. Bowden, R. J. Lunt

Experimental Summaries - Plant Research

Trial 89NO77 (89NO76)

Location: Grass Valley.

History: 1984 Lupins.

1985/86 pasture legumes and about 100 kg super/ha.

1987 Wheat yield of 2.8 t/ha using 45 kg DAP/ha and 60 of urea 2-4 WAS.

1988 Gungurru lupins (27 kg/ha seed) yielding 1.9 t/ha using 80 kg super/ha.

Tactical nitrogen trials - summary of treatments required.

Trial 89NO77

Location: Meckering

Treatments existed of nitrogen and urea. Nitrogen was not applied at seeding. Urea was applied at seeding.

Trial 88No77

Tactical nitrogen trials. - summary of observations.

Location: Grass Valley.

Trial 89NO76

Hand harvest 23/11/1989.
Yield components for copper sufficient plots reps. I …


Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson Jan 1989

Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson

Publications (WR)

Echograms have been used extensively to locate and estimate the relative abundance of marine fish stocks (Cushing 1973). In freshwater, echograms have been used to describe vertical (Netsch et al. 1971; Eggers 1978; O'Brien et al. 1984; Matthews et al. 1985), spatial (O'Brien et al. 1984; Wanjala et al. 1986) and temporal (Baker and Paulson 1983) patterns in fish abundance. Although most uses of echograms have been qualitative, Mullan and Applegate (1969) and Matthews et al. (1985) obtained relative estimates of fish abundance by counting targets (fish) on echograms. However, neither Mullan and Applegate (1969) nor Matthews et al. (1985) …


Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control Jan 1989

Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control

Maine Collection

Maine Nonpoint Source Pollution Assessment Report

Prepared by the Maine Department of Environmental Protection, Bureau of Water Quality Control, Augusta, Maine 1989.

Contents: Executive Summary / Introduction / Methodology / Statewide Water Quality Summary / State And Local Agency Programs for Control of Nonpoint Source Pollution / Process for Identification of Best Management Practices and Associated Standards / List of References / List of Figures / List of Tables



Meristic And Morphometric Comparison Of Three Juvenile Alosa Species: Blueback Herring, A Aestivalis; Alewife, A Pseudoharengus; And American Shad, A Sapidissima, Joseph C. Desfosse Jan 1989

Meristic And Morphometric Comparison Of Three Juvenile Alosa Species: Blueback Herring, A Aestivalis; Alewife, A Pseudoharengus; And American Shad, A Sapidissima, Joseph C. Desfosse

Dissertations, Theses, and Masters Projects

No abstract provided.


Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser Jan 1989

Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser

Life Sciences Faculty Research

Plant water relations of five obligate ripar-ian species were studied along California's North Fork Kings River. Diurnal stomatal conductance, transpi-ration, and xylem pressure potentials were measured throughout the 1986 growing season and in mid-season in 1987. Patterns were similar for all species although absolute values varied considerably. Maximum stomatal conductance occurred early in the day and season during favorable environmental conditions and decreased as air temperature and the vapor pressure difference between the leaf and air increased. Maximum transpiration rates occurred in mid-morning and mid-summer resulting in estimated daily water losses per unit sunlit leaf area of 163-328 mol H2O …


Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox Jan 1989

Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox

Life Sciences Faculty Research

We investigated the water relations of obli-gate riparian plants on paired diverted and undiverted reaches on Bishop Creek, Eastern Sierra Nevada. Ri-parian plants on diverted reaches had reduced stomatal conductance and water potential compared to plants on undiverted reaches in a dry year, but not in a high runoff year. Juvenile plants on diverted reaches had reduced stomatal conductance and lower midday water potentials relative to surrounding mature trees, a trend that was not observed on undiverted reaches. Plants on diverted reaches possessed significantly smaller, thicker leaves and a reduced total leaf area relative to trees on streamside reaches. Reduced …


An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith Jan 1989

An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith

Life Sciences Faculty Research

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into Bishop Creek below the headwaters is primarily derived from ground water. The average δD and δ18O values are significantly different for surface water and ground water that an isotopic analysis can delineate between these two components of flow. Therefore isotopic shifts along the creek can determine gaining reaches. In addition, by knowing …


Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt Jan 1989

Tactical Nitrogen Decisions For Wheat (And Nitrogen Sources Rates And Times On Wheat), J. W. Bowden, R. J. Lunt

Experimental Summaries - Plant Research

Trial 89MO49

Location: Tenderloin, Brand Highway, Regan's Ford.

History:

1987 Aroona wheat with 70 kg DAP and 3 kg CuSO4 at seeding followed by 60 urea at 3WAS and another 40 urea at 6WAS. Yield was about 1.7 to 1.8 t/ha;
1988 Gungurru lupins with 120 kg super and manganese/ha yielded 1.9 t/ha. 350-400 ml Roundup/ha and one cultivation prior to seeding.


Pcb Congener Analysis With Hall Electrolytic Conductivity Detection, Robert D. Edstrom Jan 1989

Pcb Congener Analysis With Hall Electrolytic Conductivity Detection, Robert D. Edstrom

Dissertations, Theses, and Masters Projects

This work reports the development of an analytical methodology for the analysis of PCB congeners based on integrating relative retention data provided by other researchers. The retention data were transposed into a multiple retention marker system which provided good precision in the calculation of relative retention indices for PCB congener analysis. Analytical run times for the developed methodology were approximately one hour using a commercially available GC capillary column. A Tracor Model 700A Hall Electrolytic Conductivity Detector (HECD) was employed in the GC detection of Aroclor standards and environmental samples. Responses by the HECD provided good sensitivity and were reasonably …


The Influence Of Tributyltin On Various Aspects Of Activation And Reactive Oxygen Formation In Oyster Toadfish (Opsanus Tau) Macrophages, Charles D. Rice Jan 1989

The Influence Of Tributyltin On Various Aspects Of Activation And Reactive Oxygen Formation In Oyster Toadfish (Opsanus Tau) Macrophages, Charles D. Rice

Dissertations, Theses, and Masters Projects

The effects of tributyltin (TBT) on phorbol myristate acetate (PMA)- and calcium ionophore (A23187)-stimulated peritoneal macrophages from oyster toadfish (Opsanus tau) were evaluated in a luminol-dependent chemiluminescence (CL) assay. PMA-stimulated CL responses were increased by in vitro exposure to 50 ug/L TBT, but depressed to baseline values by 500 ug/L TBT. A23187-stimulated CL increased with 5 ug/L and 50 ug/L TBT, and depressed by 500 ug/L TBT. Responses stimulated by synergistic doses of PMA and A23187 were increased by 50 ug/L TBT and depressed by 500 ug/L TBT. Enhanced PMA- and A23187-stimulated CL following TBT exposure returned to baseline values …