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Full-Text Articles in Physical Sciences and Mathematics

A Study Of Phytoplankton Dynamics In Lake Fayetteville As A Means Of Assessing Water Quality, Richard L. Meyer Aug 1971

A Study Of Phytoplankton Dynamics In Lake Fayetteville As A Means Of Assessing Water Quality, Richard L. Meyer

Technical Reports

Phytoplankton community was analyzed for seasonal and vertical distribution in Lake Fayetteville. This northwest Arkansas reservoir maintains a stable water level and chemical input with a relatively constant, slow overflow. Its source is groundwater seepage through a calcareous substrate with little contribution from the limited drainage basin. Phytoplankton community development with its associations and assemblages, chlorophylls -a, -b and c, and biomass distribution are described. The seasonal cycles of the chemical parameters NH4-N, NO2-N, NO3-N, ortho-phosphate, silicon, pH, HCO3- and total-alkalinity plus oxygen are described and discussed. The physical parameters of temperature, light and climate are included. The interaction of …


Interim Report On Water Quality Investigation Degray Reservoir, Arkansas, J. Nix Jul 1971

Interim Report On Water Quality Investigation Degray Reservoir, Arkansas, J. Nix

Technical Reports

Impoundment of the Caddo River near Arkadelphia, Arkansas began in August, 1969. Detailed patterns of the dissolved oxygen distribution in this reservoir are presented for the period September, 1969 through April, 1971. Although the reservoir had not reached normal pool elevation, thermal stratification accompanied by severe hypolimnic oxygen depletion has been observed. The dissolved oxygen data show that an under flow occurs in the fall of the year and carries dissolved oxygen into the hypolimnic zone. The gradients of dissolved oxygen concentration observed during the winter indicate that the reservoir does not undergo complete mixing. A short summary of the …


Impoundment Effects On Water Quality As Reflected In Parasitism Of Reservoir Basses, David A. Becker Jan 1971

Impoundment Effects On Water Quality As Reflected In Parasitism Of Reservoir Basses, David A. Becker

Technical Reports

Our aquatic environments are rapidly becoming useless as natural resources through pollution from various sources. It is therefore necessary for us to further understand the various means which relate to this process. The interrelationships between the physico-chemical and biological water qualities undergo marked changes during the ageing of a reservoir. Eutrophication of these impoundments render them rela-tively useless as natural resources. It thus becomes apparent that we must gain further knowledge of these processes if we are to devise methods for proper reservoir management.


Environmental Changes Produced By Cold-Water Outlets From Three Arkansas Reservoirs, Carl E. Hoffman, Raj V. Kilambi Jan 1971

Environmental Changes Produced By Cold-Water Outlets From Three Arkansas Reservoirs, Carl E. Hoffman, Raj V. Kilambi

Technical Reports

Water qualities of two natural streams (Buffalo and Kings Rivers), one new coId-tailwater (Beaver), and two old coId-tailwaters (Norfork and Bull Shoals) in northwestern Arkansas were studied from July 1965 through October 1968. The essential difference between the old cold-tailwaters and natural streams is a change in water quality which allows the development of a new productive ecological environment. Features which typify the old tailwaters are as follows: (1) relatively homioithermal temperatures; (2) stream beds scoured by strong hydoelectric power generation currents; (3) abundant phytoplankton and benthic macroinvertebrates; and (4) absence of warm water game fishes. Environmental factors characterizing natural …


Digital Systems For On-Site Collection For Water Quality Analysis, M. K. Testerman Nov 1970

Digital Systems For On-Site Collection For Water Quality Analysis, M. K. Testerman

Technical Reports

A prototype system has been developed for recording and transmitting digital data at a remote water quality monitoring station in an unattended manner. As many as eight analog signals from transducers, which measure water quality characteristics such as dissolved oxygen, temperature, pH, chlorides, conductivity, redox, and turbidity, are converted to digital signals and recorded in binary coded decimal format on magnetic tape. This unit may be contacted from a central station for playback of the day's recording. The transmitted data can be recorded at the central station by teletype. Each data record includes a time-of-day "word" so that all data …


Distribution Of Trace Elements In Impoundments, J. Nix Jan 1970

Distribution Of Trace Elements In Impoundments, J. Nix

Technical Reports

An investigation of the trace element content of two impoundments on the Ouachita River, Arkansas, was conducted. Common water quality parameters were followed in the reservoirs in an effort to determine the factors which were influencing the trace element concentration. The following trace metals were determined in both the particulate phase (retained by a 0.45 micron filter) and the soluble phase (passed by a 0.45 micron filter): iron, manganese, copper, cobalt, nickel, lead, chromium, and zinc. These measurements were made periodically for one and a half years. Results indicate that the chemical regime of the impoundments which were studied was …


Water Resources Planning Study For Arkansas And Oklahoma, L. R. Heiple, H. M. Jeffus Jan 1970

Water Resources Planning Study For Arkansas And Oklahoma, L. R. Heiple, H. M. Jeffus

Technical Reports

The purpose of this study is to make an appraisal of the local water resources in the Arkansas River Basin common to the two States of Arkansas and Oklahoma as defined by the Arkansas-Oklahoma Compact Committee (hereinafter referred to as "the Compact Committee"). A review, analysis, and correlation has been made of hydrologic data previously collected by others. Consideration is given to the evaluation at selected sites of the storage and potential use of existing water sources.


Virus Movement In Groundwater Systems, William A. Drewry Sep 1969

Virus Movement In Groundwater Systems, William A. Drewry

Technical Reports

The purpose of this study is to investigate the extent to which soil acts as an agent in the transmission of waterborne viruses. Since many waterborne outbreaks of viral diseases have involved small wellwater supplies contaminated by effluents from subsurface wastewater disposal systems, there is a great need for such information. Results of this study show that virus adsorption by soils is greatly affected by the pH, ionic strength, and soil-water ratio of the soil-water system and various soil properties. Also, it is shown that one cannot predict the relative virus adsorbing ability of a particular soil based on the …


Subsurface Irrigation Research In Arkansas, John P. Hoskyn, Billy B. Bryan Jun 1969

Subsurface Irrigation Research In Arkansas, John P. Hoskyn, Billy B. Bryan

Technical Reports

A pilot study conducted in 1963 indicated that (1) cotton yields could be increased by subirrigation, (2) drilled orifices were unsatisfactory because of internal plugging caused by burrs and drilling particles, and (3) operating pressures of 5 and 10 psi were excessive, and 5 psi probably should be considered as an upper-limit pressure. A greenhouse study of a subirrigation system indicated that 2 psi should, in general, for in-wall orifices, be considered as a lower-limit pressure when orifices are built into the pipe wall. The greenhouse study also indicated that a placement depth of 12 inches was preferable to 18 …


Arkansas Water Resources: Supply, Use, And Research Needs, Jared Sparks Jan 1967

Arkansas Water Resources: Supply, Use, And Research Needs, Jared Sparks

Technical Reports

The purpose of this study is to identify Arkansas’ water resources research needs against an economic backdrop of water supply and use conditions existing in the state. In the aggregate Arkansas has an abundance of high quality water relative to present use. There are local conditions that give rise to water problems, but, in general, critical water problems in Arkansas are emergent and potential rather than actual. The causes of these problems are to be found, in large part, in the economic, legal, and social institutions surrounding water use--and particularly in the economic institutions. Research designed to improve economic efficiency …


Quantitative Analysis Of Stream Flow Rate Extremes, Hugh M. Jeffus Jan 1967

Quantitative Analysis Of Stream Flow Rate Extremes, Hugh M. Jeffus

Technical Reports

Stream discharge data for the State of Arkansas is analyzed for representative statistical parameters. The statistical distribution most applicable to stream discharge data in Arkansas is the Pearson type III skew frequency curve. The parameters of the Pearson type III curve for all available records in Arkansas are included as Appendix A. The parameters of the logarithmically normal frequency distribution are included as Appendix B for mean daily discharge, minimum daily discharge and instantaneous minimum daily discharge. The logarithmically normal frequency distribution may be used for the lower discharge rates in lieu of the Pearson type III distribution except where …