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Nitrogen Cycling In Microcosms And Application To The Biology Of The Northern Arm Of The Great Salt Lake, John C. Stube, Frederick J. Post, Donald B. Porcella Jan 1976

Nitrogen Cycling In Microcosms And Application To The Biology Of The Northern Arm Of The Great Salt Lake, John C. Stube, Frederick J. Post, Donald B. Porcella

Reports

No abstract provided.


User Oriented Systems Analysis For Regional Municipal Water Supply Planning, Paul E. Pugner, Trevor C. Hughes Jan 1976

User Oriented Systems Analysis For Regional Municipal Water Supply Planning, Paul E. Pugner, Trevor C. Hughes

Reports

No abstract provided.


Iron Dynamics In A Gas-Water-Sediment Microcosm, Peter A. Cowan, V. Dean Adams, Donald B. Porcella Jan 1976

Iron Dynamics In A Gas-Water-Sediment Microcosm, Peter A. Cowan, V. Dean Adams, Donald B. Porcella

Reports

Iron dynamics in eutrophic systems were studied in the laboratory utilizing gas-water-Sediment phase sealed microcosms. Sediments from Hyrum Reservoir (2.4 percent iron by weight) were placed in the dark to simulate the hypolimnetic regions of a eutrophic impoundment. Iron both chemically and physically was readily available to microorganisms of the aqueous phase because iron in these systems was soluble. In the light microcosms, which simulated shallow littoral regions of eutrophic impoundments, iron was found in higher aqueous phase concentrations than was predicted chemically and physically; this was rationalized through biological mechanisms. The experiment was conducted in two phases: Phase I …


The Prairie Naturalist Vol. 7, No.4. December 1975 Dec 1975

The Prairie Naturalist Vol. 7, No.4. December 1975

The Prairie Naturalist

COMPARISON OF FLOWERING RECORDS FROM KANSAS AND NORTH DAKOTA ▪ O. A. Stevens

REPAIRED BONE BREAK IN A HOUSE SPARROW ▪ C. L. Cink and T. K. Broschat

A LARGE RACOON LITTER ▪ E. K. Fritzell and J. W. Matthews

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA –1975 ▪ R. N. Randall

BOOK REVIEW

Autumn Hawk Migrations ▪ P. B. Hofslund


Analysis Of The Sediment Filtering Action Of Grassed Media, Billy J. Barfield, David T. Y. Kao, E. W. Tollner Dec 1975

Analysis Of The Sediment Filtering Action Of Grassed Media, Billy J. Barfield, David T. Y. Kao, E. W. Tollner

KWRRI Research Reports

The movement of sediment in non-submerged flow through a rigid grass media was studied experimentally by simulating the media with cylindrical nails. Models of sediment movement were developed from probablistic reasoning and from the use of existing parameters describing total bed material in open channel flow. In the probability analysis, the percent sediment trapped was found to be a power function of the number of potential fall paths, Nf,a particle could make from the surface to the bed while traveling through the filter media. The percent trapped was also found to be an inverse power function of the …


Tertiary Treatment Of Wastewater Using Oxidation Ponds, Robert A. Lauderdale, John R. Moeller, Raymond D. Hamilton Dec 1975

Tertiary Treatment Of Wastewater Using Oxidation Ponds, Robert A. Lauderdale, John R. Moeller, Raymond D. Hamilton

KWRRI Research Reports

The purpose of the project was to determine the value of using lagoons as a supplemental process for treating the effluent from an activated sludge wastewater treatment plant.

Only tentative conclusions can be suggested since the project was not carried to completion. It appears that lagoons will have only minimal effect on the amounts of total nitrogen and phosphate in the plant effluent, although conversion of a portion of the ammonia to nitrate can be expected. However, the concentration of ammonia was never lower than that required by EPA guidelines. Some reduction of soluble BOD appears to occur, perhaps through …


Water Current, Volume 7, No. 8, November/December 1975 Nov 1975

Water Current, Volume 7, No. 8, November/December 1975

Water Current Newsletter

From the Desk of the Director
Last Call for Research Proposals
Water Resources Seminar
Title II Award From OWRT
Matching Grant Proposals Submitted to OWRT
OWRC Advisory Council Meets
Water Research in Nebraska
New Interior Secretary Confirmed
WRC Legislation Signed by President Ford
Water Research and Technology Advisory Panel Meeting
Research Review: Application of Enzyme Methods to the Determinination of Pollutants in Water


Computer Sheets, Walter A. Lawrance Oct 1975

Computer Sheets, Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Brown Co. Shut Down Period, Walter A. Lawrance Oct 1975

Brown Co. Shut Down Period, Walter A. Lawrance

Walter Lawrance Papers

No abstract provided.


Trace Metals And Major Elements In Water-Soluble Rocks Of Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry Jr. Oct 1975

Trace Metals And Major Elements In Water-Soluble Rocks Of Northwest Arkansas, George H. Wagner, Kenneth F. Steele, Doy L. Zachry Jr.

Arkansas Water Resources Center Technical Reports

Trace metals in limestone are potential water contaminants because they can enter the ground water when the limestone is dissolved by carbonic acid and other naturally occurring acids. Four local limestones, the St. Joe and Pitkin Formations (Mississippian) and the Brentwood and Kessler Members of the Bloyd Formation (Pennsylvanian) were sampled in a five county area in Northwest Arkansas. Atomic absorption analyses were made for Na, K, Mg, Ca, Zh, Cu, Ba, Fe, Co, Cr, Ni, Mn, Li and Sr on the acid soluble material of the samples. All the limestones are relatively pure CaCO3 with Pitkin the purest, 93.4%. …


An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price Oct 1975

An Engineering Solution To Improve Water Quality In A Tidal Lagoon, Richard Warren Price

Civil & Environmental Engineering Theses & Dissertations

Rising demand for better water quality stimulated research and development of ways to improve the quality level in existing as well as proposed water systems. At present, most of the solutions focus on biological and chemical processes.

Many natural or man-made water bodies act as receivers for both point and non-point pollution sources. Employment of biological and chemical treatment has proved successful in many of these cases; however, in some cases a more natural physical solution of an engineering mode would be more desirable. A "flushing" technique using the tidal fluctuation as a driving force has been investigated and the …


Isolation And Characterization Of Two Sterols From The Green Alga, Selenastrum Capricornutum, Raymond Mark Owings Aug 1975

Isolation And Characterization Of Two Sterols From The Green Alga, Selenastrum Capricornutum, Raymond Mark Owings

Dissertations and Theses

The green alga, Selenastrum capricornutum, was cultured in artificial nutrient medium utilizing five-gallon carboys, each of which contained 16 1. of culture. The algal cells were separated from the nutrient medium by continuous-flow centrifugation at 7500 RPM, and were then lyophilized. The lyophilized cells were extracted by refluxing with ether, acetone, and chloroform:methanol (2:1). Free sterols and sterol esters were separated from the crude extract using preparative thin-layer chromatography. Sterol esters were saponified and both the sterols and the fatty acids were recovered.

Individual sterols were separated from the free sterol fraction using argentation thin-layer chromatography. Gas chromatograms, mass …


Trace Element Composition Of Stream Sediments An Integrating Factor For Water Quality, Kenneth F. Steele, Harold C. Macdonald, George H. Wagner, William S. Bowen Jun 1975

Trace Element Composition Of Stream Sediments An Integrating Factor For Water Quality, Kenneth F. Steele, Harold C. Macdonald, George H. Wagner, William S. Bowen

Arkansas Water Resources Center Technical Reports

Bottom sediments, suspended sediments, and water were sampled along 130 miles of the Buffalo River in northern Arkansas. The water and acid extracts of the suspended sediments and the minus 95 mesh fraction of the bottom sediments were analyzed by atomic absorption spectrometry. All samples were analyzed for Na, K, Mg, Ca, Zn, Cd, Cu, Pb, Fe, Co, Cr, Ni, and Mn. Selected bottom samples also were analyzed by As, Hg, and Zr. Zr was determined by x-ray fluorescence. Li and Sr were determined for selected water and suspended sediment samples. There is a general decrease downstream in Fe, Cu, …


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 …


Pollution Abatement From Cattle Feedlots In Northeastern Colorado And Nebraska, L. K. Porter, F. G. Viets Jr., T. M. Mccalla, L. F. Elliott, F. A. Norstadt, H. R. Duke, N. P. Swanson, L. N. Mielke, G. L. Hutchinson., A. R. Mosier, G. E. Schuman, Lynn R. Shuyler, C. E. Evans Jun 1975

Pollution Abatement From Cattle Feedlots In Northeastern Colorado And Nebraska, L. K. Porter, F. G. Viets Jr., T. M. Mccalla, L. F. Elliott, F. A. Norstadt, H. R. Duke, N. P. Swanson, L. N. Mielke, G. L. Hutchinson., A. R. Mosier, G. E. Schuman, Lynn R. Shuyler, C. E. Evans

United States Environmental Protection Agency: Publications

Climatic factors, feedlot runoff, and organic material in the runoff were evaluated in experimental and commercial feedlots. The effects of slope, stocking rates, terraces, basins, and holding ponds were evaluated to obtain the best controls for containing runoff. In eastern Nebraska, 70 cm annual precipitation produces 23 cm of runoff; whereas, in northeastern Colorado, 37 cm annual precipitation gives only 5.5 cm of runoff. Large applications of runoff liquid, up to 91 cmon grass-Ladino and 76 cm on corn, in Nebraska did not decrease yields; however, in northeastern Colorado, the concentrated high-salt runoff required dilution before direct application to crops. …


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 …


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 …


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 …


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.


Accuracy Of Lysimetric, Energy Balance, And Stability-Corrected Aerodynamic Methods Of Estimating Above-Canopy Flux Of Co2, S. B. Verma, N. J. Rosenberg Jan 1975

Accuracy Of Lysimetric, Energy Balance, And Stability-Corrected Aerodynamic Methods Of Estimating Above-Canopy Flux Of Co2, S. B. Verma, N. J. Rosenberg

School of Natural Resources: Faculty Publications

No abstract provided.


Phenology And Function Of Sonoran Desert Annuals In Relation To Environmental Changes, D. T. Patten Jan 1975

Phenology And Function Of Sonoran Desert Annuals In Relation To Environmental Changes, D. T. Patten

Progress reports

No abstract provided.


Plant Growth And Water Transfer Interactive Process Under Desert Conditions, D. D. Evans, T. W. Sammis Jan 1975

Plant Growth And Water Transfer Interactive Process Under Desert Conditions, D. D. Evans, T. W. Sammis

Progress reports

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.


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.


Data Search For Aquatic Model, J. Perry Ii, G. W. Minshall Jan 1975

Data Search For Aquatic Model, J. Perry Ii, G. W. Minshall

Memorandum

No abstract provided.


Use Of The Normal Generating Distribution For Estimating Population Survival, H. C. Romesburg Jan 1975

Use Of The Normal Generating Distribution For Estimating Population Survival, H. C. Romesburg

Progress reports

No abstract provided.


Factors Affecting Seed Reserves In The Soil Of A Desert Ecosystem, R. M. Chew, J. F. Nelson Jan 1975

Factors Affecting Seed Reserves In The Soil Of A Desert Ecosystem, R. M. Chew, J. F. Nelson

Progress reports

No abstract provided.


Regionalization As An Effect Of Offshore Oil And Gas Exploitation: A Case Study Of The North Sea, Mark J. Chittum Jan 1975

Regionalization As An Effect Of Offshore Oil And Gas Exploitation: A Case Study Of The North Sea, Mark J. Chittum

Marine Affairs Theses and Major Papers

This study attempts to analyze whether oil and gas exploitation in a semi-enclosed sea will result in closer relations being developed in the region leading to the establishment of a special regime for that sea. The study area is Northwestern Europe which is centered on the North Sea. All the littoral states of Northwestern Europe have major interests in the North Sea, one of which is oil and gas exploitation. This study is developed through the examination of the activities in the North Sea, related to oil and gas production, which tend to join the region together followed by an …


Fisheries Report No 19 - The Western Rock Lobster Fishery 1973 - 1974, G. R. Morgan, E H. Barker Jan 1975

Fisheries Report No 19 - The Western Rock Lobster Fishery 1973 - 1974, G. R. Morgan, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster* is one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably stable catches. Inherent …