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Survival And Growth Rate Of Channel Catfish As A Function Of Dissolved-Oxygen Concentration, R. W. Raible Jun 1975

Survival And Growth Rate Of Channel Catfish As A Function Of Dissolved-Oxygen Concentration, R. W. Raible

Arkansas Water Resources Center Technical Reports

Channel catfish were raised in water-recirculating systems for several periods of about six months duration each. Initial stock was fingerling size fish (10 to 20 grams). At dissolved-oxygen levels below 2.5 parts per million, mortality was high. Fish raised in tanks held at dissolved-oxygen levels between 3.0 and 6.8 parts per million showed increased gains of weight for each increment of added oxygen. Weight gains were as much as 50 percent higher at 6.8 parts per million compared with weights at 3.0 parts per million. Feed conversion was good in all cases. When feeding was limited to demand, feed conversion …


Movement Of Pesticides In The Soil Water Fertilizer System, H. Don Scott Jun 1975

Movement Of Pesticides In The Soil Water Fertilizer System, H. Don Scott

Arkansas Water Resources Center Technical Reports

A theoretical and experimental study of the transport of pesticides was conducted in several Arkansas soils with metribuzin, a herbicide. In a field study, chloride and metribuzin were applied to a Captina silt loam under maximum leaching conditions and their redistribution was compared with that of soil water. Metribuzin was found in significantly detectable quantities to a depth of 61 cm; the largest concentrations were detected in the surface 23 cm and particularly in the 0-5 cm increment. Two days after application 72.6 and 33.6% could be detected in the vegetation and no-vegetation plots. The metribuzin half life was 7.88 …


Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase Ii, Richard L. Meyer Jun 1975

Biochrome Analysis As A Method For Assessing Phytoplankton Dynamics Phase Ii, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

Selected chemical, physical and biological parameters were determined for a man-made lake, Beaver Lake, on the White River of Arkansas and Missouri. The research program determined the qualitative and quantitative aspects of the temporal and spatial distribution of the algal subcommunities. It was determined that the epipelic, epilithic, epizooic and metaphytic subcommunities had little influence on the euplanktonic subcommunity. The relationship between the qualitative and quantitative analysis of the biochromes chlorophyll-a, -b, and -c and the phytoplankton species clustered into biochrome sets is discussed. The temporal and spatial distributional patterns of temperature, oxygen, ammonia-N, nitrate-N, orthophosphate-P and silicates are described …


Vegetation Development In Relation To Age Of River Stabilization Structures Along A Channelized Segment Of The Missouri River, John Arthur Vaubel Jun 1975

Vegetation Development In Relation To Age Of River Stabilization Structures Along A Channelized Segment Of The Missouri River, John Arthur Vaubel

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

During the summer of 1974, I sampled sites of vegetation representative of successional trends in plant communities along the Missouri River floodplain from Sioux City, Iowa, to Rulo, Nebraska. Five district community types listed from youngest to oldest are as follows: Salix spp. – dominated, Populus deltoides – dominated, Platanus occidentalis-Ulmus rubra – dominated, Tilia americana-Quercus rubra – dominated, and Quercus macrocarpa-Carya ovata – dominated vegetation.

The technique of relating vegetation succession to age of river stabilization structures was found to be useful and offered a quite precise method of developing a timescale …


The Effects Of Artificial Destratification On The Water Quality And Microbial Populations Of Hyrum Reservoir, Douglas D. Drury, Donald B. Porcella, Robert A. Gearheart Jun 1975

The Effects Of Artificial Destratification On The Water Quality And Microbial Populations Of Hyrum Reservoir, Douglas D. Drury, Donald B. Porcella, Robert A. Gearheart

Reports

Artificial destratification is being increasingly used in attempts to improve water quality and control eutrophication. Most of the artificial destratification efforts are being conducted by public water supply utilities in efforts to improve reservoir water quality for culinary purposes. At present, artificial destratification is being conducted without a complete understanding of the process or its effects on the reservoir. Whether or not artificial destratification can control algal growth and other microbial processes is a controversial question. The effect of artificial destratification on the microbial flora must be understood if it is to be used effectively as a management tool in …


The Effect Of Human Activity On The Middle Course Of The Tualatin River, Oregon, Lolita M. Carter May 1975

The Effect Of Human Activity On The Middle Course Of The Tualatin River, Oregon, Lolita M. Carter

Dissertations and Theses

A diurnal study of biological, chemical, and physical parameters was made on the middle course of the, Tualatin River, which drains a 1840 km2 (711 mi2) basin adjacent to metropolitan Portland, Oregon. This portion of the river lies along land in transition of use from rural agriculture to highly urbanized development.

There is no nutrient loading of the river from farming practices because there was no return of water from summer, sprinkler irrigation of commercial crops. However, irrigation significantly reduces the volume of water in the river in the summers.

Effluents from sewage treatment plants flowing into …


An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection May 1975

An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection

Storrs Agricultural Experiment Station

No abstract provided.


Evaluation Of Recovery In A Polluted Creek After Installation Of New Sewage Treatment Procedures, Robert A. Kuehne May 1975

Evaluation Of Recovery In A Polluted Creek After Installation Of New Sewage Treatment Procedures, Robert A. Kuehne

KWRRI Research Reports

Response of Hickman Creek near Lexington, Kentucky to alleviation from serious sewage pollution was studied from January, 1973 through July, 1974. Wastes are now handled from an efficient secondary treatment facility and four sequential polishing lagoons before chlorination and discharge to West Hickman branch.

Physico-chemical tests gave no strong indication of residual pollution effects at the start of the study, approximately six months after the treatment facility opened. At low flow a slight oxygen sag, probably associated with algal growth in the lagoons, persists downstream from the outfall. Mean values for turbidity, nitrates and COD are somewhat higher at the …


Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki May 1975

Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki

Publications (WR)

The 14C light and dark bottle technique for measurement of primary production was utilized as a means of assessing the amount of inorganic carbon being converted Into organic form by the photosynthesis of phytoplankton populations In the Boulder Basin of Lake Mead.

Spatial and time series changes of productivity levels observed at eight sampling locations within Boulder Basin Indicate that the Influence of treated municipal arts' industrial effluent flowing into Les Vegas Bay is contributing high levels of available nutrients at Las Vegas Wash Inlet to cause productivity to approximate those levels associated with polluted waters.

Productivity levels at …


Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson May 1975

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …


Water Quality Impact Of Burning And Grazing On A Chained Pinyon-Juniper Site In Southeastern Utah, John C. Buckhouse May 1975

Water Quality Impact Of Burning And Grazing On A Chained Pinyon-Juniper Site In Southeastern Utah, John C. Buckhouse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During 1973 and 1974 a water quality study was conducted in San Juan County, southeastern Utah. In 1973, baseline water quality data was collected from study locations which had been chained to remove pinyon-juniper vegetation six years earlier. The area had been chained under two different techniques: (1) doubled chained, with debris-left-in-place and (2) chained, with debris windrowed. An "undisturbed, natural" woodland was left between these two treatments in order to serve as a control area.

In the fall of 1973 and spring of 1974 secondary treatments of burning and grazing were superimposed upon the debris-in-place and windrowed sites, respectively. …


Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal May 1975

Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The upper optimum temperature for embryonic development of mountain whitefish is 6 C, and for the post yolk sac stage is 9 to 12 C. The need to know effects on all stages in the life cycle in cases of thermal pollution is demonstrated. Abnormalities caused by thermal pollution in hatched larvae were agape jaws, coloboma or fissure of the eye, monophthalmia or the presence of only one eye, monomicrophthalmia or the presence of one small eye and one case of twinning. High mortalities of eggs occurred at 9 C and higher.

Study of the energy expenditure, by the dry …


Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz May 1975

Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties.

The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime …


Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray May 1975

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two intermediate wheatgrass seedings with different levels of grass bug infestation were evaluated for herbage production, seedhead production, percent dry matter, crude protein, and cell contents. Study sites were located at different elevations on mountain summer ranges in northern (Site I) and central (Site II) Utah. Study plots at Site I and Site II were infested with 113 and 210 bugs per sweep, respectively. Herbage production appeared to be reduced in early spring on the site with the higher infestation; however, no effect on season-long herbage production could be detected on either site. Seedhead production on infested plots was reduced …


Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski May 1975

Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The framework of a stream ecosystem simulation model is described. Using this framework and data from two different geographical areas, a cold desert stream and a generalized mountain stream, exploratory sensitivity analysis was performed on the model. This was accomplished by qualitatively comparing outputs of a series of simulations in which a different level of a driving variable was used in each simulation. Based on these results, recommendations are made for improving the structure of the model.


Water Current, Volume 7, No. 4, April 1975 Apr 1975

Water Current, Volume 7, No. 4, April 1975

Water Current Newsletter

Why Plan for Water and Land Resource Management?
Duane Acker to Head Kansas State
Nebraska Water Quality Report
Funds Requested for MRBC Yellowstone Study
Agreement Reached on Water Marketing
Old West Governors Challenge Corps Power
Water Crisis Predicted
EPA Drinking Water Survey Shows Possible Carcinogens
Water Resources Scientific Information Center
National Drinking Water Advisory Council Named
Pollution Tax Urged
Research Review: Biological Control of Blue-Green Algae


The Effects Of Sewage Pollution Abatement On Environmental Quality In Hillsborough Bay, Florida, Joseph J. Simon, Wen H. Huang Mar 1975

The Effects Of Sewage Pollution Abatement On Environmental Quality In Hillsborough Bay, Florida, Joseph J. Simon, Wen H. Huang

Reports

Owing to the construction of a large municipal advanced (tertiary) waste water treatment (AWT) plant, a unique opportunity exists to study the side effects of removal of a major point source of pollution on the estuarine environment of Hillsborough Bay. The data is still in more or less raw form, with little analyses or interpretation attempted to date.


Final Report: Buffalo National River Ecosystems, R. E. Babcock, H. C. Macdonald, D. G. Parker, Joe F. Nix, Kenneth F. Steele, Richard L. Meyer, R. W. Raible, D. A. Becker, R. V. Kilambi, E. H. Schmitz Mar 1975

Final Report: Buffalo National River Ecosystems, R. E. Babcock, H. C. Macdonald, D. G. Parker, Joe F. Nix, Kenneth F. Steele, Richard L. Meyer, R. W. Raible, D. A. Becker, R. V. Kilambi, E. H. Schmitz

Arkansas Water Resources Center Technical Reports

The objective of this study was to sample the Buffalo River on a seasonal basis for a year, in order to determine whether any potential water quality problems existed.


Water Current, Volume 7, No. 3, March 1975 Mar 1975

Water Current, Volume 7, No. 3, March 1975

Water Current Newsletter

From the Desk of the Director
Search for NWRRI Director Proceeding
New Address for Former NWRRI Director
Institute Publications
1975 Nebraska Water Conference Review
Underground Water Pumping Bill to Legislature
Environmental Specialist Joins MRBC Planning Staff
FY 1976 Proposed Water Budgets
Water Resources Council Begins Study on Cost Sharing
FEA Projects Rail and Barge Shortages for Coal Transport
Research Review: Biophysical Control of Water Loss
Butcher Named Water Research Director


The Prairie Naturalist Volume 7, No.1. March 1975 Mar 1975

The Prairie Naturalist Volume 7, No.1. March 1975

The Prairie Naturalist

MIGRATION OF BIRDS IN NORTH DAKOTA DURING FAll 1974 ▪ J. T. Lokemoen & D. H. Johnson.

REPRODUCTION AND DEVELOPMENT OF FOUR MALLARD LINES ▪ R. J. Greenwood


Water Current, Volume 7, No. 2, February 1975 Feb 1975

Water Current, Volume 7, No. 2, February 1975

Water Current Newsletter

From the Desk of the Director
Institute Director Resigns
Search for NWRRI Director Underway
NWRRI Research Seminar
Institute Publications
MRBC Water Resources Priorities Set
Safe Drinking Water Bill Signed
Graduate Study in Water Resources
Research Review: Investigation of Laser Ramen Spectroscopy for Analysis of Water Quality


Distribution And Relative Abundance Of Billfishes (Istiophoridae) Of The Indian Ocean, John Kenneth Howard, Walter A. Starck Ii Jan 1975

Distribution And Relative Abundance Of Billfishes (Istiophoridae) Of The Indian Ocean, John Kenneth Howard, Walter A. Starck Ii

Studies in Tropical Oceanography

No abstract provided.


Limnological Observations On A Small River, Donald G. Kaddatz Jan 1975

Limnological Observations On A Small River, Donald G. Kaddatz

Journal of the Minnesota Academy of Science

Limnological conditions were studied in the Snake river at Mora, in east-central Minnesota, over a 13- month period. Sampling stations were established above and below the sewage outfall from the city of Mora to assess the river's physical and chemical parameters. Seasonal changes and fluctuations related to discharge flow were observed and recorded.


Effects Of Grazing On Desert Vegetation, B. E. Norton Jan 1975

Effects Of Grazing On Desert Vegetation, B. E. Norton

Progress reports

No abstract provided.


The Impacts Associated With Energy Developments In Carbon And Emery Counties, Utah Part Iii: Land, Water And Air Resources And Possible Conflicts Of Their Use, Rodney D. Millar Jan 1975

The Impacts Associated With Energy Developments In Carbon And Emery Counties, Utah Part Iii: Land, Water And Air Resources And Possible Conflicts Of Their Use, Rodney D. Millar

Elusive Documents

No abstract provided.


Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor Jan 1975

Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor

Memorandum

No abstract provided.


Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher Jan 1975

Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher

Memorandum

No abstract provided.


Biology Of Nematodes In Desert Ecosystems, D. W. Freckman, R. Mankau, S. A. Sher Jan 1975

Biology Of Nematodes In Desert Ecosystems, D. W. Freckman, R. Mankau, S. A. Sher

Memorandum

No abstract provided.


Conceptualization And Early Development Of A Water Response Ecosystem Model, D. C. Wilkin, P. W. Lommen, J. V. Robinson, G. S. Innis Jan 1975

Conceptualization And Early Development Of A Water Response Ecosystem Model, D. C. Wilkin, P. W. Lommen, J. V. Robinson, G. S. Innis

Memorandum

No abstract provided.


Measurement Of Evapotranspiration With A Monolith Lysimeter, D. W. Young, D. D. Evans, T. W. Sammis Jan 1975

Measurement Of Evapotranspiration With A Monolith Lysimeter, D. W. Young, D. D. Evans, T. W. Sammis

Memorandum

No abstract provided.