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Articles 76621 - 76650 of 78558
Full-Text Articles in Entire DC Network
Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner
Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner
Bulletin of the University of Nebraska State Museum (1924–2023)
The distribution and evolution of Late Cenozoic tapirs are discussed and the forms present in Nebraska are reported. Two new species are described from the Ogallala Pliocene of Nebraska, ?Tapirus johnsoni and ?T. simpsoni. Tapirs are known in Nebraska from the Early Oligocene through the Middle Pleistocene. The northern limit of the distribution of the tapirs contracts gradually southward in North America throughout the Tertiary, and even during the Pleistocene interglacials Nebraska must have been near the northern limit of their range.
Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner
Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner
Bulletin of the University of Nebraska State Museum (1924–2023)
Study of Teleoceras remains in the University of Nebraska State Museum indicates that this specialized, short-limbed rhinoceros inhabited the Central Great Plains from Early through Late Pliocene. Previously thought to have become extinct at the end of the middle Pliocene, this genus is now known from the very latest Pliocene. A new species, Teleoceras schultzi, is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska.
Rates Of Water Entry Into The Subsoil Of Several Soil Series In Nebraska, David T. Lewis
Rates Of Water Entry Into The Subsoil Of Several Soil Series In Nebraska, David T. Lewis
Nebraska Agricultural Experiment Station: Historical Research Bulletins
Rates of water entry were measured for 11 soil series representing many of the soils in parts of Nebraska where urban growth is most intensive. The wetting procedure in making the tests is critical and a 24 hour wetting time as usually recommended is not adequate for all soils if the percolation test is made during a dry season. Rates of water entry differed among soils even though a large amount of variation was evident within the same soil series. Statistical analysis showed a highly significant negative relationship between both clay content and bulk density and rates of water entry. …
Extracts From The Department Of Agriculture's Annual Report, 1974-75, Department Of Agriculture, Western Australia
Extracts From The Department Of Agriculture's Annual Report, 1974-75, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
The Department of Agriculture's Annual Report for the year ended June 30, 1975, took the form of short reviews of selected activities of the Department during the year.
Some of these reviews are reprinted below to give an idea of the range of activities undertaken by the Department. A limited number of copies of the full report are available to interested organisations from the Department of Agriculture, Jarrah Road, South Perth, 6151.
In past years the Department's report has taken the form of a relatively detailed technical summary of the work of each Division. Because of the large volume of …
1975 Trials On Doublegee, D J. Gilbey
1975 Trials On Doublegee, D J. Gilbey
Experimental Summaries - Plant Research
75A16, 75A17, 75C13, 75MO36, 75MO37, 75WH21, 75WH22. Biological control of doublegee.
Texas Eastern University Catalog, 1975-1976, University Of Texas At Tyler
Texas Eastern University Catalog, 1975-1976, University Of Texas At Tyler
Catalogs
No abstract provided.
Food Habits Of Young-Of-The-Year Fishes In Abbey Pond, South Dakota, Randall D. Radant
Food Habits Of Young-Of-The-Year Fishes In Abbey Pond, South Dakota, Randall D. Radant
Electronic Theses and Dissertations
Food habits of young-of-the-year largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus), black crappie (Pomoxis nigromaculatus), yellow bullhead (Ictalurus natalis), and yellow perch (Perca flavescens) were studied during 1973 and 1974 in Abbey Pond, South Dakota. Organisms found in young-of-the-year fish stomachs and in plankton samples were identified and counted in the laboratory. Zooplankton, aquatic insects and fish were the most important food organisms consumed by young fishes. Using Ivlev’s electivity index food electivity by the fishes for zooplankton was calculated. The size-specific food habits of young-of-the-year largemouth bass progressed from entomostracans to aquatic insects to fish. In most cases zooplanktons …
Process Control Of Activated Sludge Treatment, Phase Ii, Richard I. Kermode, Robert W. J. Brett, Joseph D. Pault Jr.
Process Control Of Activated Sludge Treatment, Phase Ii, Richard I. Kermode, Robert W. J. Brett, Joseph D. Pault Jr.
KWRRI Research Reports
Material balances on substrate and microorganisms were derived in conjunction with various mixing configurations thought to accurately describe the activated sludge process. These models include the completely mixed with bypass, plug flow, and plug flow with bypass. Two sets of kinetic mechanisms for substrate utilization and bacterial growth were employed.
A feed forward controller was designed from linear approximations of the material balances derived in the completely mixed with bypass mixing model. Utilizing frequency response methods, the controller was found essentially identical to a completely mixed modeled controller developed in a prior investigation.
Through computer simulation the controller's effectiveness was …
A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr
A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr
Masters Theses
Gross primary productivity, heterotrophic bacterial numbers, and net phytoplankton densities of seven ponds in Coles County, Illinois, were studied in relation to physical, chemical, and biological habitat variables (light intensity and duration, turbidity, water temperature, pH, dissolved oxygen, sulfur, nitrogen, phosphorus, production, bacteria, and phytoplankton). Ten observations were made for each pond (except where otherwise noted) from 17 June through 25 August 1974. Stepwise multiple linear regression analyses of the data were used in order to determine those environmental factors which were important in predicting (i.e., significantly correlated with) bacterial and phytoplankton densities, and production. A multiple linear regression equation …
Discriminant Function Analysis, Kuo Hsiung Su
Discriminant Function Analysis, Kuo Hsiung Su
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
The technique of discriminant function analysis was originated by R.A. Fisher and first applied by Barnard (1935). Two very useful summaries of the recent work in this technique can be found in Hodges (1950) and in Tosuoka and Tiedeman (1954). The techniques have been used primarily in the fields of anthropology, psychology, biology, medicine, and education, and have only begun to be applied to other fields in recent years.
Classification and discriminant function analyses are two phases in the attempt to predict which of several populations an observation might be a member of, on the basis of multivariate measurements. Both …
Food Habits, Growth, And Production Of Young-Of-The-Year Walleyes, Stizostedion Vitreum Vitreum (Mitchell), In A South Dakota Pond, Ronne E. Walker
Food Habits, Growth, And Production Of Young-Of-The-Year Walleyes, Stizostedion Vitreum Vitreum (Mitchell), In A South Dakota Pond, Ronne E. Walker
Electronic Theses and Dissertations
A 12.45 hectare South Dakota pond was stocked with 25,000 walleye, Stizostedion vitreum vitreum (Mitichell), fingerling on 13 June, 1973. Walleyes were monitored for growth rate and food habits until 13 September, 1973. Walleyes were removed from the pond using various methods in order to evaluate the efficiency of removal methods. The average total length and average weight of walleyes in the pond increased from 43.5 mm and 0.50 g on 13 June to 167.1 mm and 41.25 g on 13 September. This was a gain of 123. 6 mm and 40.75 g or an average daily increase of 1.34 …
A Field Technique Measuring Virus Decay And Potential Aerosol Hazard From Wastewater Sprinkler Irrigation, Michael F. Torpy, Robert A. Gearheart, J. Clifton Spendlove, Rex S. Spendlove
A Field Technique Measuring Virus Decay And Potential Aerosol Hazard From Wastewater Sprinkler Irrigation, Michael F. Torpy, Robert A. Gearheart, J. Clifton Spendlove, Rex S. Spendlove
Reports
The increased use of domestic wastewater for irrigation purposes has stimulated a growing practice of sprinkler irrigating from oxidation ponds and other domestic wastewaters. Aerosols generated from these sprinkler irrigation systems may contain potentially hazardous pathogens. Subsequently, the aerosols can contain infective viruses which can be carried through the air to surrounding populations. Thus, a public health hazard can be created by sprinkler irrigating domestic wastewater. This study is an investigation of a means by which the virus decay rate of viruses in aerosols and the potentials hazard of sprinkler irrigation aerosol clouds may be examined. A means of injection …
Development Of A Management Framework Of The Great Salt Lake, J. Paul Riley, Calvin G. Clyde, William J. Grenney, Yacov Y. Haimes, Craig T. Jones
Development Of A Management Framework Of The Great Salt Lake, J. Paul Riley, Calvin G. Clyde, William J. Grenney, Yacov Y. Haimes, Craig T. Jones
Reports
No abstract provided.
Nutrient Dynamics And Gas Production In Aquatic Ecosystems: The Effects And Utilization Of Mercury And Nitrogen In Sediment-Water Microcosms, D. B. Porcella, V. D. Adams, P. A. Cowan, S. Austrheim-Smith, W F. Holmes, J. Hill Iv, W. J. Grenney, E. J. Middlebrooks
Nutrient Dynamics And Gas Production In Aquatic Ecosystems: The Effects And Utilization Of Mercury And Nitrogen In Sediment-Water Microcosms, D. B. Porcella, V. D. Adams, P. A. Cowan, S. Austrheim-Smith, W F. Holmes, J. Hill Iv, W. J. Grenney, E. J. Middlebrooks
Reports
Sixteen sediment-water microcosms designed to allow complete gas, liquid, and solid mass balances of gases, nutrients, and mercury were studies under dark conditions or varying light intensity for a period of 189 days. Results indicated that the microcosm technique is a very sensitive method of analyzing microbial dynamics in sediment water systems. Gas quantity and composition changes were easy to monitor and were especially sensitive to light and nutrient variations. Nitrogen fixation occurred in all lighted systems (blue-green algae nitrogen fixers, Anabaena, and others) and was adequate to insure that no nitrogen limitation occurred even though nitrogen limitation was imposed …
Biostimulation And Nutrient Assessment, Thomas E. Mahoney, A. G. Payne, C. M. Weiss, W. E. Miller, J. C. Greene, T. Shiroyama, R. A. Soltero, A. F. Gasperino, D. T. Specht, R. M. Gerhold, P. D. Uttormark, J. P. Wall, J. H. Reynolds, E. J. Middlebrooks
Biostimulation And Nutrient Assessment, Thomas E. Mahoney, A. G. Payne, C. M. Weiss, W. E. Miller, J. C. Greene, T. Shiroyama, R. A. Soltero, A. F. Gasperino, D. T. Specht, R. M. Gerhold, P. D. Uttormark, J. P. Wall, J. H. Reynolds, E. J. Middlebrooks
Reports
No abstract provided.
Colorado River Regional Assessment Study Part One: Executive Summary, Basin Profile, And Report Digest, Utah Water Research Laboratory
Colorado River Regional Assessment Study Part One: Executive Summary, Basin Profile, And Report Digest, Utah Water Research Laboratory
Reports
No abstract provided.
Colorado River Regional Assessment Study Part Two: Detailed Analyses: Narrative Description, Data, Methodology, And Documentation, Utah Water Research Laboratory
Colorado River Regional Assessment Study Part Two: Detailed Analyses: Narrative Description, Data, Methodology, And Documentation, Utah Water Research Laboratory
Reports
No abstract provided.
Modeling Phytoplankton Blooms In A Stratified Embayment, William J. Grenney
Modeling Phytoplankton Blooms In A Stratified Embayment, William J. Grenney
Reports
A mathematical model was developed to simulate the nitrogen limited growth dynamics of phytoplankton in a stratefied embayment. The representation of biological growth dynamics includes consideration of intracellular nutrient storage as well as the effects of temperature and light intensity. Several competing species can be represented simultaneously. Model hydrodynamics represent the effects of vertical mixing in the water column on the physical distribution of nutrients and phytoplankton. Sinking velocities of the cells are also included. The model was applied to Auke Bay, Alaska, and model responses are compared to data observed during the spring and summer of 1967.
Naturally Occurring Organic Compounds And Algal Growth In A Eutrophic Lake, V. Dean Adams, Russell R. Renk, Peter A. Cowan, Donald B. Porcella
Naturally Occurring Organic Compounds And Algal Growth In A Eutrophic Lake, V. Dean Adams, Russell R. Renk, Peter A. Cowan, Donald B. Porcella
Reports
No abstract provided.
Watershed Management On Range And Forest Lands Proceedings Of The Fifth Workshop Of The United States/Australia Rangelands Panel, R. J. Mcconnen, B. S. Sadler, Colin L. Pierrehumbert, Kenneth G. Renard, Donald L. Brakensiek, Alden R. Hibbert, T. Talsma, C. W. Rose, Ronald E. Sosebee, Richard Meeuwig, Paul Packer, Walter C. Boughton, J. Paul Riley, Richard H. Hawkins
Watershed Management On Range And Forest Lands Proceedings Of The Fifth Workshop Of The United States/Australia Rangelands Panel, R. J. Mcconnen, B. S. Sadler, Colin L. Pierrehumbert, Kenneth G. Renard, Donald L. Brakensiek, Alden R. Hibbert, T. Talsma, C. W. Rose, Ronald E. Sosebee, Richard Meeuwig, Paul Packer, Walter C. Boughton, J. Paul Riley, Richard H. Hawkins
Reports
Preface: The U.S.-Australia Cooperative Rangeland Science Program In October 1968 the governments of the United States and Australia entered into an agreement for the purpose of facilitating close cooperative activities between the scientific communities of the two countries. The joint communique issued at that time designated the U.S. National Science Foundation and the Australian Commonwealth Department of Education and Science as the coordinating agencies. Both countries were to encourage binational teamwork in research, interchanges of scientists, joint seminars, and exchanges of information. A United States-Australia Rangeland Panel was established in December 1969 to further cooperation between the two countries in …
Raising Wood Ducks, Richard L. Nelson
Raising Wood Ducks, Richard L. Nelson
Nebraska Game and Parks Commission: Publications
Numbered among Nature's most colorful creatures, wood ducks willingly accept a helping hand from man in establishing new homes. These birds adapt well to suitable habitat, and you can play an important part in bringing the wood duck to locations where they do not now nest. For groups or individuals who are willing to expend the effort necessary to undertake a wood duck restoration project anti see it to completion, it is an exceptional gift from today's generation to those of decades and centuries to come. Many areas in Nebraska provide suitable wood duck habitat, but do not have a …
Water Current, Volume 7, No. 1, January 1975
Water Current, Volume 7, No. 1, January 1975
Water Current Newsletter
From the Desk of the Director
Conference Held on Research in Action
NWRRI Research Seminar
Nebraska First in NPDES Program
Resignations and Retirements from OWRT
Future Water Crisis Noted
Horton Outlines Federal Water Policy
Research Review: Seasonsal Water Use of Irrigated Pasture Grasses Under Permanent-Set Irrigation as Related to Climatic Factors
Effect Of Feedlots On Water Quality, Ronald D. Cheetham, Alan J. Holmes, David Borresen
Effect Of Feedlots On Water Quality, Ronald D. Cheetham, Alan J. Holmes, David Borresen
Journal of the Minnesota Academy of Science
The effect of feedlot runoff on water quality was examined. Samples were collected from river feedlots and offshore from lake feedlots and compared with samples from appropriate control sites. Bacterial contamination, as measured by the total coliform test over two successive summers, exhibited significant variation between feedlot and control sites. Coliform levels at lake sites adjacent to feedlots were double the levels at control sites; while in river systems average coliform levels downstream from feedlots were approximately 17 times the upstream controls.
Mixing Effects On Shallow Water Bodies, Kim Robin Powell
Mixing Effects On Shallow Water Bodies, Kim Robin Powell
Retrospective Theses and Dissertations
This report is intended to examine the ecological changes due to mixing in shallow water bodies. Physical, chemical, and biological changes are reported in literature. A literature search revealed the range of mixing nodes or processes. Assessment of ecological changes due to mixing by boating activities had been evaluated in a research project supported by the environmental Protection Agency and conducted at Florida Technological University. The examination of changes due to mechanical mixing on lake ecology simulated in fifty-five gallon drums indicated the sensitivity of such parameters as total Kjeldahl nitrogen, conductivity, pH, temperature, and dissolved oxygen. Problems of reproducibility …
Plating Wastewater Management, Earl Kenneth Ossorio
Plating Wastewater Management, Earl Kenneth Ossorio
Retrospective Theses and Dissertations
A study was made of existing methods of management, treatment and disposal of water and wastewater effluents at a large aerospace facility (Martin Marietta Aerospace) in Central Florida. Water consumption and handling were evaluated, with emphasis being placed on the handling of plating wastes, since they are the main contributor of industrial wastewater pollutants at the facility. The flow, storage, and treatment of the plating wastes were studied. Literature concerning plating wastes was surveyed to determine the latest "state of the art" on handling of plating pollutants. Then, the "state of the art" processes were compared with the existing processes …
Colorado River Regional Assessment Study Part Three: Area-Specific Water Quality Analysis And Environmental Assessment, Utah Water Research Laboratory
Colorado River Regional Assessment Study Part Three: Area-Specific Water Quality Analysis And Environmental Assessment, Utah Water Research Laboratory
Reports
The Colorado River Bain contains the most diverse environment setting of any American river. High mountainous elevations (>14,000 feet) are ultimately succeeded by sea level plains and low valleys. Geological structures and formations include deep, intricately carved river canyons, high mountain slopes, large saline shale structures, and long verdant irrigated river valleys. Fir forests are succeeded by arid rangelands. The river produces the lowest outflow per unit area (60 acre feet per square mile) of any river basin in the United States. It contains the largest number of unique and endangered species in the United States. Finally, it is …
A Technique For Predicting The Aquatic Ecosystem Response To Weather Modification, Eugene K. Israelsen, David R. Bernard, Thomas M. Twedt, Henry M. Runke
A Technique For Predicting The Aquatic Ecosystem Response To Weather Modification, Eugene K. Israelsen, David R. Bernard, Thomas M. Twedt, Henry M. Runke
Reports
In the past, considerable effort has been spent on the development of techniques for increasing precipitation from a given cloud formation. However, little attention has been given to identifying and evaluating the impacts of cloud seeing activities on the aquatic ecosystems within the affected areas. The objective of this study was to apply the simulation technique to predict the impacts of cloud seeing on the aquatic ecosystem within the area subject to weather modification. A small mountain watershed near Logan, Utah, was selected for the study. Measurements were made of the significant parameter levels under current conditions. A hydrologic and …
77-4 Hydrographic And Biological Observations At An Anchor Station Off St. Augustine, Florida (Eastward Cruise E-1g-75), Larry P. Atkinson, Gustav A. Paffenhofer, William M. Dunstan
77-4 Hydrographic And Biological Observations At An Anchor Station Off St. Augustine, Florida (Eastward Cruise E-1g-75), Larry P. Atkinson, Gustav A. Paffenhofer, William M. Dunstan
CCPO Publications
The intrusion of deep, nutrient-rich Gulf Stream water into the shelf waters off the southeastern United States is probably the major source of nutrients in the shelf waters and consequently intrusions have a major impact on the biota. This particular cruise was one of the first to be designed to find the front that represents the interface between intruding Gulf Stream waters and normal shelf water. Once the front was delineated an anchor station was occupied to observe the time change at a particular location as the front moved back and forth past the station.
The methods used and resultant …
The Keller Plan In College Introductory Physical Geology : A Comparison With The Conventional Teaching Method, Robert G. Walsh Sr.
The Keller Plan In College Introductory Physical Geology : A Comparison With The Conventional Teaching Method, Robert G. Walsh Sr.
Theses and Dissertations
The purpose of this study is to compare the learning and attitudinal changes that took place in a college introductory physical geology class between a self-paced method of instruction called the Keller Plan and the conventional lecture-laboratory method.
The sample population was 56 students enrolled in Earth Science 120, an introductory physical geology course at Minot State College ·~ during the fall quarter, 1973. An experimental section of 20 students experienced the Keller Plan treatment and two control groups consisting of 18 students each received the conventional method of instruction.
Four specific areas of investigation were tested: (1) knowledge of …
Natural Science Of The Great Plains As It Relates To The American Indian : A Syllabus And Sourcebook, Mary E. Bluemle
Natural Science Of The Great Plains As It Relates To The American Indian : A Syllabus And Sourcebook, Mary E. Bluemle
Theses and Dissertations
This dissertation, which includes a sourcebook of pertinent reference materials, sample lesson plans, and natural science roadlogs, is an initial attempt at providing an Indian Studies field course in natural science. It also includes a syllabus which stresses natural science processes and serves as a unifying factor for field work, lecture, and course discussions. The dissertation stresses geographical and ecological concepts, climatic and geological processes, and the natural habitats of North Dakota. It includes discussions of North Dakota vertebrates and early man and his relation to his environment; discussions of_ the geologic features, geologic history, vegetation and animal life of …