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Full-Text Articles in Physical Sciences and Mathematics

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 ...


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

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 ...


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

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 7 ...


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

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.


Yorktown Power Station Ecological Study, Phase Ii : Final Technical Report, R. A. Jordan, R. W. Virnstein, J. E. Illowsky, J. Colvocoresses May 1975

Yorktown Power Station Ecological Study, Phase Ii : Final Technical Report, R. A. Jordan, R. W. Virnstein, J. E. Illowsky, J. Colvocoresses

Reports

No abstract provided.


A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum

A new species of Pliocene peccary, Prosthennops (Macrogens) graffhami; is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska. This new species is the latest in geologic age and most advanced in the genus.

The remains of fossil vertebrates are generally rare in the upper part of the Ogallala group, and some have maintained that Hemphillian faunas such as Coffee Ranch and Smith County, Kansas, represent the latest Ogallala faunas. Later faunas than are typically considered as Hemphillian, containing more advanced forms, occur in the Kimball Formation and deposits of equivalent age. Known faunas which may be close to ...


Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum

A ramus and partial premaxilla establish the presence of a new subspecies of Indarctos in the upper Pliocene (Kimball Formation, Ogallala Group) of Frontier County, Nebraska. An extremely large species of Agriotherium is represented by fragmentary remains from the middle Pliocene (middle part of Ash Hollow Formation, Ogallala Group) of Sherman County, Nebraska.

This study is part of a series of papers dealing primarily with the fauna of the Kimball formation in Nebraska (Barbour 1927, 1929; Barbour and Schultz, 1941; Schultz and Stout, 1948, 1961; Kent 1963, 1967; Tanner, 1967; Short, 1969; Martin and Tate, 1970; Schultz, Schultz, and Martin ...


Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner Feb 1975

Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum

Includes:

Part 1. Middle and Late Cenozoic Tapirs from Nebraska. By C. Bertrand Schultz, Larry D. Martin, and R. George Corner.

Part 2. Stratigraphic Occurrences of Teleoceras, with a New Kimballian Species from Nebraska. By Lloyd G. Tanner.

Part 3. A New Kimballian Peccary from Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 4. Bears (Ursidae) from the Late Cenozoic of Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 5. Scimitar-toothed Cats, Machairodus and Nimravides, from the Pliocene of Kansas and Nebraska. By Larry D. Martin and C. Bertrand Schultz.

84 pp


Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz Feb 1975

Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

"Machairodus catocopis Cope" is shown to be a pseudaelurin cat belonging to the genus Nimravides Kitts. Nimravides thinobates (Macdonald) is a possible synonym of N. catocopis (Cope). Nimravides is compared with the Eurasian Machairodus-like cat, Dinofelis. Machairodus (Heterofelis) coloradensis is reported from the Kimball Formation, upper Pliocene (Kimballian) of Cheyenne County, Nebraska, and from the upper part of the Ash Hollow Formation, Pliocene (Hemphillian) of Sherman County, Nebraska. The Kimballian form is described as a new subspecies, Machairodus coloradensis tanneri.

The genus Machairodus has long been associated with the Hemphillian of North America and the Pontian of Eurasia. It ...


Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner Jan 1975

Middle And Late Cenozoic Tapirs From Nebraska, C. Bertrand Schultz, Larry D. Martin, R. George Corner

Bulletin of the University of Nebraska State Museum

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 Jan 1975

Stratigraphic Occurrences Of Teleoceras With A New Kimballianspecies From Nebraska, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum

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.


Biological Inventory In Conjunction With The Las Vegas Wash Unit, Colorado River Basin Salinity Control Act Title Ii (P.L. 93-320), W. Glen Bradley, J. Scott Miller Jan 1975

Biological Inventory In Conjunction With The Las Vegas Wash Unit, Colorado River Basin Salinity Control Act Title Ii (P.L. 93-320), W. Glen Bradley, J. Scott Miller

Publications (WR)

The present report is a biological inventory in conjunction with the Las Vegas Wash Unit, Colorado River Basin Salinity Control Act, Title II. The boundaries of the project encompass sections of North Las Vegas, Las Vegas, East Las Vegas and areas along Las Vegas Wash extending to its drainage point in Las Vegas Bay in Lake Mead. Therefore, it encompasses a wide array of ecological situations and landscapes ranging from essentially natural to various stages of urban development.

This biological inventory presents basic ecological classifications, descriptions of vegetation, lists of vascular plants and vertebrates known to occur in the area ...


A Statistical Approach To The Study Of The Ecosystems Of Seven Ponds In East-Central Illinois, Gregory Lee Orr Jan 1975

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 ...


Gill Area, Oxygen Consumption And Habitat In Four Xanthid Crabs Of The York River, Virginia, Douglas H. Wood Jan 1975

Gill Area, Oxygen Consumption And Habitat In Four Xanthid Crabs Of The York River, Virginia, Douglas H. Wood

Dissertations, Theses, and Masters Projects

No abstract provided.


Chesapeake Bay Bibliography - Volume Iii. Maryland Waters, Jane F. Stauble, Douglas H. Wood Jan 1975

Chesapeake Bay Bibliography - Volume Iii. Maryland Waters, Jane F. Stauble, Douglas H. Wood

Reports

The Chesapeake Bay Bibliography was initiated by the Virginia Institute of Marine Science in response to growing resource management problems of the Chesapeake Bay and its tributaries. With these problems came the realization that planning and management of such a great natural resource is an overwhelming task requiring the best available information. This bibliography, therefore, was undertaken to document existing sources of information, to help identify research and data gathering needs, and to develop a comprehensive research and information services programs for individuals interested in research on, and management of the natural resources of the Chesapeake Bay region.

This work ...


Chesapeake Bay Bibliography - Volume Iv. Virginia Waters, Sandra A. Gleason, Jane F. Stauble Jan 1975

Chesapeake Bay Bibliography - Volume Iv. Virginia Waters, Sandra A. Gleason, Jane F. Stauble

Reports

The Chesapeake Bay Bibliography was initiated by the Virginia Institute of Marine Science in response to growing resource management problems of the Chesapeake Bay and its tributaries. With these problems came the realization that planning and management of such a great natural resource is an overwhelming task requiring the best available information. This bibliography, therefore, was undertaken to document existing sources of information, to help identify research and data gathering needs, and to develop a comprehensive research and information services programs for individuals interested in research on, and management of the natural resources of the Chesapeake Bay region.

The Chesapeake ...


Studies For A Proposed Nansemond River Sewage Treatment Plant, Virginia Institute Of Marine Science Jan 1975

Studies For A Proposed Nansemond River Sewage Treatment Plant, Virginia Institute Of Marine Science

Reports

  • Vol. 1: Summary and conclusion/ C.S Fang and Bruce Neilson.
  • Vol. 2: An analysis of currents and circulation in Hampton Roads, Virginia / Bruce Neilson and Mark Boulé; Description of non-tidal flows / Maynard Nichols.
  • Vol. 3: Water quality monitoring of Hampton Roads and the Nansemond River, Summer 1974 / Bruce Neilson ... [et al.]
  • Vol. 4. : A survey of commercial shellfish in the vicinity of Newport News Point and Pig Point in the lower James River / Dexter Haven and Paul Kendall
  • Vol. 5: A model for predicting the pollutant distribution from an outfall in a tidal estuary / C.S. Fang and Bruce ...


Removal Of Phosphorus From Static Sewage Effluent By Waterhyacinth, W Harold Ornes Dec 1974

Removal Of Phosphorus From Static Sewage Effluent By Waterhyacinth, W Harold Ornes

W. Harold Ornes

Waterhyacinth [Eichhornia crassipes (Mart.) Solms] was grown in static sewage effluent during May to July 1974 in outdoor concrete containers with a capacity of 760 liters and a surface area of 1.66 m². The plants were removed weekly from one-half of the surface area of the containers during 5-wk growth periods. Tissue phosphorus (P) and nitrogen (N), plant productivity, and some parameters of water quality were measured. A maximum uptake of 5,500 µg of P/g dry weight of plant material occurred when the level of orthophosphate phosphorus (available P) in the effluent was 1.1 µg/ml ...