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Articles 2221 - 2250 of 2388

Full-Text Articles in Fresh Water Studies

The Comparative Ecology Of Two Populations Of The Troglobitic Isopod Crustacean Lirceus Usdagalun (Asellidae), James Alexander Estes Jan 1979

The Comparative Ecology Of Two Populations Of The Troglobitic Isopod Crustacean Lirceus Usdagalun (Asellidae), James Alexander Estes

Biological Sciences Theses & Dissertations

Aquatic communities of two caves in Lee Co., Virginia, were compared, and an examination was made of the life history phenomena of the troglobitic isopod Lirceus usdagalun. Measurements of physical and biological parameters were made in Thompson Cedar Cave and Gallohan Cave No. l. A contagious distribution was exhibited by populations of L. usdagalun in both caves and also by the population of another troglobitic isopod, Caecidotea recurvata, in Gallohan Cave No. 1. This distribution was attributed to aggregations of individuals which were considered to occur in areas of preference or optimal habitat patches. Lirceus usdagalun exhibited a …


A. Minimum Tillage Investigations. B. Evaluation Of Stubble Management Techniques, D Jasper Jan 1979

A. Minimum Tillage Investigations. B. Evaluation Of Stubble Management Techniques, D Jasper

Experimental Summaries - Plant Research

77WH17 Continuous cropping site, Wongan Hills Research Station 77WH18 Rotational site, Wongan Hills Research Station 77M13 Heavy land continuous cropping site, Merredin Research Station 78M25 Light land continuous cropping site, Merredin Research Station 77M56 Rotational site, Merredin Research Station 77A16 Continuous cropping site, Avondale Research Station 77A43 Rotational site, Avondale Research Station 77E52 Rotational site, Esperance Downs Research Station 78BA42 Continuous Cropping Site, Badgingarra Research Station 77MT15 Continuous Cropping Site, Mt Barker Research Station 79WH6, Evaluation of stubble management practices, Wongan Hills Research Station 79M6 Heavy Land, Merredin Research Station 79M7 Light land, Merredin Research Station


Barley Yellow Dwarf Virus In Barley And Oats (79mt20, 79pe13) Experimental Summary 1979, G D. Mclean, T N. Khan, M Grimm, J D. Sandow Jan 1979

Barley Yellow Dwarf Virus In Barley And Oats (79mt20, 79pe13) Experimental Summary 1979, G D. Mclean, T N. Khan, M Grimm, J D. Sandow

Experimental Summaries - Plant Research

(1) Yield assessments have continued similar to those used in 1977 and 1978. Essentially, plants with symptoms typical of BYDV are marked in the early spring as well as a similar number without symptoms. Yield differences were obtained both for Clipper Barley and an oats variety. (2) Two pilot experiments using viruliferous aphids were carried out at Mount Barker (79MT20) and at South Perth · (79PE13). Both Rhopalosiphum padi and R. maidis were used. Infection at Mt Barker failed, and therefore no data is presented. The Perth experiment was planted on August 31, 1979. The original plan was to have …


Summary Research Results 1979, G A. Pearce Jan 1979

Summary Research Results 1979, G A. Pearce

Experimental Summaries - Plant Research

DPX4189 for weed control in wheat 79N27. Location - Toodyay. Herbicide mixtures for broadleaved weeds in wheat. Location - Toodyay. Diuron mixtures for broad leaf weeds in cereals. Location - "Glencoe" C/- P.O. Bindoon. Herbicides for early planting 79MO42. Location – N. Tonkin – Coomberdale. Broad leaf weeds in cereals 79MO45. Location - Miling (J. Lewis, Plympton). Herbicides for early planting 79LG27. Location – Karlgarin.


Long Term Rotation Trials, I Rowland Jan 1979

Long Term Rotation Trials, I Rowland

Experimental Summaries - Plant Research

Locality: 66M29, 67Cl3, 67N4, 68E5, 68SG5, 73SG16. Soil type, history, rainfall and wheat/lupin yields.


Experimental Summary 1979, J R. Peirce Jan 1979

Experimental Summary 1979, J R. Peirce

Experimental Summaries - Plant Research

Contents 79ME28 Soursob (Oxalis caprae) control along Roadsides. 79NO30 A & B.

79NO29 Pre and post emergent applications of Diuron for soursob control in cereals.

79ME31 Post emergent control of soursob in cereals. 79NO39

79ME26 A & B Control of Matricaria (Pentzia sp.) in cereals.

79NO40 Dormancy of Cape Tulip (homeria sp.).

79NO38 Patersons curse (Echium plantagineum) Control in pastures. Afghan thistle (solanum hoplopetalum) Control in pastures. 79ME28 and 79N030 A & B Soursob Control Along Roadsides. Chemicals: Roundup 1, 2 and 3 1ha-1, Diuron 1, 2 and 3 1ha-1, Sencor TD 1, 2 and 3 kgha -1 ) applied …


Investigations Of Ryegrass Toxicity, B A. Stynes Jan 1979

Investigations Of Ryegrass Toxicity, B A. Stynes

Experimental Summaries - Plant Research

Development of toxicity in the field. Experiment – 79KA13. Location – C. Butterworth, Katanning. The effect of herbicides and growth regulants on gall development. Experiment – 79KA14. Location - C. Butterworth, Katanning. Effect of burning on the production of galls. Experiment – 79KA9. Location - L. Blight, Gnowangerup; K. Butterworth, Katanning; C. Hanna, Katanning; J. Shepherdson, Gnowangerup. Table 1 Previous land use and characteristics of fires at four farms where fields were burnt in autumn to reduce the level of toxicity of ryegrass in the subsequent spring pasture. Table 2 The numbers and relative proportions of galls retained in the …


Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon Jan 1979

Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon

Publications (WR)

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance …


A Limnological Study Of Ricks Pond And The Gulpha Creek Drainage In Garland County, Arkansas, Tom M. Buchanan, James Houston, Joe F. Nix, Richard L. Meyer, Eugene H. Schmitz Nov 1978

A Limnological Study Of Ricks Pond And The Gulpha Creek Drainage In Garland County, Arkansas, Tom M. Buchanan, James Houston, Joe F. Nix, Richard L. Meyer, Eugene H. Schmitz

Arkansas Water Resources Center Technical Reports

A limnological investigation of Ricks Pond and the Gulpha Creek drainage of Garland County, Arkansas was conducted between 1 June 1978, and 21 August 1978. Water samples taken from ten stations on three different dates indicated that the stream and pond systems were typical in water quality characteristics of other small, high gradient streams and impoundments in the Ouachita Mountains of Arkansas. In Ricks Pond, thermal stratification occurred along with the development of an oxygen deficient zone below a depth of one meter. Other water quality parameters indicated that Ricks Pond is a moderately productive ecosystem, with the productivity limited …


Hydrolytic And Photochemical Degradation Of Organophosphorus Pesticides, James F. Hinton Sep 1978

Hydrolytic And Photochemical Degradation Of Organophosphorus Pesticides, James F. Hinton

Arkansas Water Resources Center Technical Reports

To keep pace with demands for increasing food supplies to satisfy the expanding world population, modern agriculture has utilized the latest scientific and technological knowledge available. Increases in crop production through the use of growth regulators, fertilizers , herbicides, and insecticides have been little short of phenomenal, and drugs, feed additives, and higher-quality grain and forage have dramatically increased livestock production. But, as is usually the case, this progress has been accompanied by problems, one of the more serious being contamination of our environment by chemicals. Only in recent years have the full effects of these pollutants on the ecological …


The Effects Of Heavy Metals On Algae Populations In A South Central Reservoir, Richard L. Meyer Aug 1978

The Effects Of Heavy Metals On Algae Populations In A South Central Reservoir, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

The present investigation examines seasonal variations of algal assemblages in a south-central reservoir, Lake Fayetteville, Arkansas, in an attempt to evaluate the role of various trace metals in relation to these seasonal variations. Iron, manganese, cobalt, copper, lead and zinc concentrations were evaluated for the period of one year from March, 1976 to March, 1977 with concomitant examination of alga] assemblages. In addition to collection of this material, correlations between specific taxa and metals in the water fraction have been evaluated. A detailed literature review dealing with the role of micronutrients in various algal groups has been discussed by Rice …


Apis: Arkansas Planning Information System, William R. Draper, David B. Beasley, Theo A. Dillaha Iii, Ronald W. Skeith Jul 1978

Apis: Arkansas Planning Information System, William R. Draper, David B. Beasley, Theo A. Dillaha Iii, Ronald W. Skeith

Arkansas Water Resources Center Technical Reports

The Federal Water Pollution Control Act Amendments of 1972 call for the restoration and maintenance of the chemical, physical and biological integrity of the Nation's waters. The Act sets forth two primary goals; 1) the elimination of the discharge of all pollutants into the navigable waters of the United States by 1985 and 2) an interim level of water quality that provides for the protection of fish, shellfish, wildlife and recreation by July 1, 1983. Section 208 of the Act mandated the development and implementation of area wide water quality management plans to achieve the goals previously mentioned.


A Primary Ecological Survey Of Dardanelle Reservoir Prior To Nuclear Facility Effluent Discharge, Clarence B. Sinclair, Robert L. Watson Jun 1978

A Primary Ecological Survey Of Dardanelle Reservoir Prior To Nuclear Facility Effluent Discharge, Clarence B. Sinclair, Robert L. Watson

Arkansas Water Resources Center Technical Reports

A preliminary ecological survey of Dardanelle Reservoir during the construction phase of Arkansas Power and Light Company's nuclear generating facility was conducted from January 1970 through June 1974. The reservoir is characterized by relatively shallow depths and a high flow-thru rate. A number of features were associated with these characteristics. The reservoir carried a great deal of suspended material and exhibited high turbidities throughout most of the year. Typical thermal stratification and oxygen depletion were only rarely observed. Many of the physico-chemical parameters exhibited relatively high values in comparison to other Arkansas lakes and reservoirs, but due to absence of …


Zooplankton Limnology Of Beaver And Degray Reservoirs In Arkansas, Eugene H. Schmitz May 1978

Zooplankton Limnology Of Beaver And Degray Reservoirs In Arkansas, Eugene H. Schmitz

Arkansas Water Resources Center Technical Reports

Research during the year 1975-76 continued to emphasize studies of seasonal changes in patterns of zooplankton abundance and biomass in Beaver and DeGray Reservoirs. Zooplankton samples were taken monthly from three stations on Beaver Reservoir (Figure 1) during the period May 1975 through May 1976. Collections from DeGray Reservoir were made weekly from a single station (Station 1) during the period April 1975 through December 1975. Beaver collections were obtained by taking oblique tows using a Miller sampler equipped with no. 10 mesh. The DeGray program entailed stratified vertical samples taken at 5 intervals to 20 a and 20 m …


Primary Productivity, Water Quality, And Limiting Factors In Lake Chicot, Edmond J. Bacon Jan 1978

Primary Productivity, Water Quality, And Limiting Factors In Lake Chicot, Edmond J. Bacon

Arkansas Water Resources Center Technical Reports

Primary productivity, water quality, and limiting factors of productivity were studied in Lake Chicot from 1 July 1975 to 30 September 1977 to ascertain the ameliorating effects of a comprehensive water quality improvement project. The upper lake receives only limited local run-off, but run-off from 350 square miles of agricultural land enters the lower lake through Connerly Bayou, the principal polluted tributary. Run-off over the predominantly silt and clay soils in the subsidized agricultural area contributes excessive amounts of colloidal silt and clay to the lower lake. Connerly Bayou also contributes additional amounts of nutrients including calcium, magnesium, potassium, sodium, …


Radionuclide Concentrations In The Arkansas River Upstream And Downstream From The Nuclear I Power Generating Facility, D. M. Chittenden Ii Jan 1978

Radionuclide Concentrations In The Arkansas River Upstream And Downstream From The Nuclear I Power Generating Facility, D. M. Chittenden Ii

Arkansas Water Resources Center Technical Reports

This report summarizes results obtained from a program designed to measure very low levels of some commonly produced radionuc1ides in the Dardenelle Lake area of the Arkansas River near the Arkansas Nuclear I Power Station operated by Arkansas Power and Light Company. The main thrust of this program was to determine the increase in the concentration of the radionuclides as a result of reactor operation as a function of their distance from the source. It was hoped to extend this study to include the effects of these emissions on the uptake of radionuclides into biological systems and their deposition in …


Pre- And Post Impoundment Ichthyoparasite Succession In A New Arkansas Reservoir, David A. Becker, William D. Carr, Robert G. Heard, Donald G. Cloutman, Perry D. Holmes, Wallace A. Evans, Mitchell D. Norman, Wilbur B. Owen Jr. Jan 1978

Pre- And Post Impoundment Ichthyoparasite Succession In A New Arkansas Reservoir, David A. Becker, William D. Carr, Robert G. Heard, Donald G. Cloutman, Perry D. Holmes, Wallace A. Evans, Mitchell D. Norman, Wilbur B. Owen Jr.

Arkansas Water Resources Center Technical Reports

Helminth and crustacean parasites from 2,387 Micropterus dolomieui, M. punctulatus, and M. salmoides were utilized to monitor annual pre- and postimpoundment succession patterns spanning eight con- tinuous years in Beaver Reservoir, Arkansas. Incidence of infection by ichthyoparasites with direct life cycles (monogenetic trematodes, leeches, and crustaceans) generally increased following impoundment, although leeches remained relatively constant. Exceptions to this general pattern occurred. Incidence of ichthyoparasites with indirect life cycles (digenetic trematodes, cestodes, acanthocephalans, and nematodes) decreased immediately following impoundment with subsequent increases to a point equal or above that of preimpoundment, although exceptions occurred. Time for species adaptation to the reservoir …


Final Report Buffalo National River Ecosystems Part Iv, R. E. Babcock, E. E. Dale, R. L. Meyer, D. G. Parker, E. G. Smith, M. D. Springer Jan 1978

Final Report Buffalo National River Ecosystems Part Iv, R. E. Babcock, E. E. Dale, R. L. Meyer, D. G. Parker, E. G. Smith, M. D. Springer

Arkansas Water Resources Center Technical Reports

Sampling point locations and analytical procedures remained unchanged from those outlined in previous Buffalo National River Ecosystem reports. The only significant change in analytical procedures was a reversion to the glass fiber filter method for collection and extraction of samples for chlorophyll analysis. This change was neeessitated by a need for filtering a larger volume to obtain enough chlorophyll for an accurate measurement. Samples were collected monthly from April 9 through December 30. No samples were taken in January or February due to the extremely uncertain traveling conditions caused by the frequent snows. Prior research indicates that the December 30 …


An Evaluation Of The Effects Of Dredging Within The Arkansas River Navigation System - Volume I - Introduction, Summary And Conclusions, And Recommendations, Arkansas Water Resources Research Center Jan 1978

An Evaluation Of The Effects Of Dredging Within The Arkansas River Navigation System - Volume I - Introduction, Summary And Conclusions, And Recommendations, Arkansas Water Resources Research Center

Arkansas Water Resources Center Technical Reports

The foundation for the development of the Arkansas River was laid with the authorization of many upstream reservoirs in the comprehensive River and Harbor Act of 1946 signed by President Truman. Subsequent authorizations were forthcoming and work began on many of the bank stabilization facilities in 1950 and on the major structures in 1957. The current McClellan-Kerr Arkansas River Navigation System was substantially completed in 1972. The authorized multiple-purpose plan for the Arkansas River and tributaries provided for the construction of coordinated developments in the interests of navigation, hydroelectric power, flood control, bank stabilization, and related benefits including recreation and …


Radionuclide Concentrations In The Arkansas River Upstream And Downstream From The Nuclear Power Generating Facility, D. M. Chittenden, Ii Jan 1978

Radionuclide Concentrations In The Arkansas River Upstream And Downstream From The Nuclear Power Generating Facility, D. M. Chittenden, Ii

Arkansas Water Resources Center Technical Reports

No abstract provided.


Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden Jan 1978

Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden

Publications (WR)

This publication offers an in-depth study of the fish and other organisms that live in Lakes Mead and Mohave. The history and background of the two lakes is offered, as well as information about diseases, parasites, and unusual fish occurrences. Food sources, predation and competition are also discussed.


Water Resources Aspects Of Coal Transportation By Slurry Pipeline, James W. Moore Dec 1977

Water Resources Aspects Of Coal Transportation By Slurry Pipeline, James W. Moore

Arkansas Water Resources Center Technical Reports

No abstract provided.


Water Conservation In Industrial Filtration Operations, Jim L. Turpin Sep 1977

Water Conservation In Industrial Filtration Operations, Jim L. Turpin

Arkansas Water Resources Center Technical Reports

The washing of a solute from filter cakes was investigated for both saturated and unsaturated washing conditions. Systems used in this experimental study were 0.065 NaCl solution as the filtrate in an aluminum hydrate filter cake and 0.1 Normal HCL solution as the filtrate in a column packed with glass beads. The filtrate concentration as a function of the flow rate of wash water and of the volume of effluent from the packed bed was measured. The amounts of filtrate removed from the bed during saturated washing, and washing employing repetitive steps of saturation followed by evacuation were compared. Also, …


Final Report: Lake Mead Monitoring Program, James E. Deacon Sep 1977

Final Report: Lake Mead Monitoring Program, James E. Deacon

Publications (WR)

The Lake Mead Monitoring Program has continued to develop information on the limnological condition of Lake Mead. We have significantly increased our analytical capabilities this year by developing a cooperative project with the U.S. Bureau of Reclamation and continuing our cooperative program with E.P.A. We also were able to derive significant benefit from the reviews of the Pollution Abatement Project written by Clair Sawyer and Charles Goldman. Partially as a result of these reviews we have had the opportunity to interpret and more fully explain the significance of our work to a wider public audience than would otherwise have been …


Population Dynamics And Species Diversity Of Ichthyo-Parasitofauna Of The Buffalo National River, Raj V. Kilambi, David A. Becker Aug 1977

Population Dynamics And Species Diversity Of Ichthyo-Parasitofauna Of The Buffalo National River, Raj V. Kilambi, David A. Becker

Arkansas Water Resources Center Technical Reports

The Buffalo River originates in the Ozark plateau in Newton County, Arkansas. This magnificent Ozarkian wilderness river is about 238 km long and flows north-eastward to its confluence with the White River. The Buffalo River drains 3,465 km2 and has some 30 named tributaries. In its upper reaches, huge multicolored cliffs extend nearly 213 m above the river as it flows through mountainous countryside which reaches an elevation of 732 m. Within its watershed may be found 700 species of plant life, a habitat for 250 species of birds, and a variety of game animals. In its aquatic habitat …


An Investigation Of Using Derivation Reaction Gas Chromatography To Measure Anionic Water Quality Parameters, Richard H. Hanson Jun 1977

An Investigation Of Using Derivation Reaction Gas Chromatography To Measure Anionic Water Quality Parameters, Richard H. Hanson

Arkansas Water Resources Center Technical Reports

A new analytical method has been developed which provides researchers with another way to measure orthophosphate content in aqueous samples. The reaction gas chromatographic system was capable of analyzing orthophosphate in the range from 0.25 - 5.0 micrograms of P in 50 microliters of aqueous sample. Flame ionization proved to be the most successful detector. The primary advantage of this technique was the small volume of sample required.


Buffalo National River Ecosystem - Part Iii, M. D. Springer, E. B. Smith, D. G. Parker, R. L. Meyer, E. E. Dale, R. E. Babcock Jun 1977

Buffalo National River Ecosystem - Part Iii, M. D. Springer, E. B. Smith, D. G. Parker, R. L. Meyer, E. E. Dale, R. E. Babcock

Arkansas Water Resources Center Technical Reports

Samples for water quality analyses and phycological studies were taken from the nine standard sampling locations on the Buffalo River nine times during the period from March 1976 through February 1977. The April-June 1976 samples represent nearly identical conditions throughout the spring period; therefore, emphasis was placed on taxonomic research. As the early January sample was considered sufficient~y reflective of stable winter conditions, the December and February periods were. used for detailed microscopic examination of the rich and diverse diatom flora that was found in the river this year. A total of 273 taxa of diatoms were identified from the …


Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation Jun 1977

Limnological Aspects Of Lake Mead, Nevada-Arizona, John R. Baker, James E. Deacon, Thomas A. Burke, Samuel S. Egdorf, Larry J. Paulson, Richard W. Tew, Bureau Of Reclamation

Publications (WR)

Lake Mead is a deep, subtropical, moderately productive, desert impoundment with a negative heterograde oxygen profile occurring during; the summer stratification. investigations of the Boulder Basin of Lake Mead by the University of Nevada were initiated in November 1971. The primary objective of the study was to determine what effects industrial and sewage effluent from the Las Vegas metropolitan area, discharged into Las Vegas Bay, have had on the water quality and limnological conditions of Boulder Basin. Data from the 1975-76 period are presented in detail, with earlier data included in the summaries and discussions. Measurements of water temperature, dissolved …


The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke Apr 1977

The Limnetic Zooplankton Community Of Boulder Basin, Lake Mead In Relation To The Metalimnetic Oxygen Minimum, Thomas A. Burke

Publications (WR)

The limnetic zooplankton community of Boulder Basin, Lake Mead, was examined to determine the role of this community in the development of a metalimnetic oxygen minimum which regularly occurs in the lake. Analysis of the community from May 1975 to April 1976 revealed that zooplankton maintain high populations within the metalimnion during summer stratification. The species composition of the community changes noticeably during the summer, but due to advanced stages excysting from resting forms, a complete assemblage of individuals are found throughout the 74 day period studied. Thermal stratification was weak, covering a 30 meter metalimnion. Eddy currents powered by …


Landsat Linear Trend Analysis - A Tool For Groundwater Exploration In Northern Arkansas, H. C. Macdonald, Kenneth F. Steele, Elizabeth Gaines Jan 1977

Landsat Linear Trend Analysis - A Tool For Groundwater Exploration In Northern Arkansas, H. C. Macdonald, Kenneth F. Steele, Elizabeth Gaines

Arkansas Water Resources Center Technical Reports

Intelligent development of groundwater resources is a process that requires a thorough understanding of the availability and movement of groundwater. In northern Arkansas knowledge of the deep aquifers is fairly limited, perhaps because economic factors and uncertain yields have discouraged exploitation. The development of these deeper aquifers to their fullest potential as reliable water sources depends on the delineation of high yield areas, a process that may be facilitated by linear trend analysis as outlined in this study. Satellite and photolineament maps of the 13 counties were prepared by use of LANDSAT images and Agricultural Stabilization and Conservation Service photo …