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Seed Reserves Of Desert Soils, Stuart Childs, David W. Goodall May 1973

Seed Reserves Of Desert Soils, Stuart Childs, David W. Goodall

Memorandum

No abstract provided.


1972 Progress Report: Soil As A Factor In Modelling The Phosphorus Cycle In The Desert Ecosystem, J. J. Jurinak, R. A. Griffin May 1973

1972 Progress Report: Soil As A Factor In Modelling The Phosphorus Cycle In The Desert Ecosystem, J. J. Jurinak, R. A. Griffin

Elusive Documents

The research conducted in 1972 emphasized a nutrient assay of soil from the Curlew Valley site, phosphorus inventory of the vegetation and rabbit droppings, and further chemical characterization of soil phosphorus, which also included determination of the kinetics and energetics of the calcium carbonate-phosphate system.


Distillation-Condensation Of Water And Nutrient Movement In A Desert Ecosystem, N. Stark May 1973

Distillation-Condensation Of Water And Nutrient Movement In A Desert Ecosystem, N. Stark

Memorandum

No abstract provided.


Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor, D. C. Prusso May 1973

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

Memorandum

No abstract provided.


Proteolytic Activity Of Soil Microorganisms, Robert T. O'Brien May 1973

Proteolytic Activity Of Soil Microorganisms, Robert T. O'Brien

Memorandum

No abstract provided.


Chemical Quality Of The Groundwater System In Hall County, Nebraska, Jon C. Atkinson May 1973

Chemical Quality Of The Groundwater System In Hall County, Nebraska, Jon C. Atkinson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Hall County, an area of 540 square miles, is in south-central Nebraska. The Platte River flows east-northeasterly across the county from its southwest corner; the Wood River, which is tributary to the Platte within Hall County, enters the county about 6 miles north of the southwest corner. Analysis of streamflow data indicates that the Platte and Wood Rivers are losing streams in Hall County. Based on an 18-year period, October 1953 through September 1971, the average annual losses between gaging stations were 48,100 and 1,940 acre-feet, respectively.

The county is underlain by unconsolidated deposits of Quaternary age. These deposits mantle …


Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline May 1973

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …


Glacial Geology Of The Western Catskills, James Totten Kirkland May 1973

Glacial Geology Of The Western Catskills, James Totten Kirkland

Graduate Dissertations and Theses

Ic0 flow directions on the glaciated Appalachian Plateau in central New York were from the Adirondack Hountains. This is demonstrated by both striae directions and erratic provena..-1ce studies. No evidence for more than one Wisconsin glaciation as suggested by Rich (1935) could be found. Theories for local glaciation during the decline and after the retreat of the Laurentide Ice Sheet were also unsubstantiated. The East and West Branches Delaware River had different styles of daglaciation. The West Branch is characterized by zones of stagnation. The length of a zone is controlled by relief of the valley and corresponds to that …


Petrology And Regional Relationships Of The Ordovician Kinnikinic Formation And Equivalents, Central And Southern Idaho, William Calvin James May 1973

Petrology And Regional Relationships Of The Ordovician Kinnikinic Formation And Equivalents, Central And Southern Idaho, William Calvin James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Kinnikinic Formation of central Idaho is a sedimentary unit consisting principally of orthoquartzite. From its maximum measured thickness of 2285 feet in the central Lemhi Range near Gilmore, Idaho, it thins westward to 376 feet at the type section and southward to 326 feet near Arco, Idaho. Northeast of the Lemhi Range it occurs only as erosional remnants, due to pre-Devonian erosion. Both the lower and upper contacts of the Kinnikinic Formation are disconformable.

The Kinnikinic Formation is light colored, predominately fine to medium grained, thin to medium bedded, and largely cemented by silica overgrowths. Some metamorphic recrystallization has …


Petrology And Geochemistry Of The Morrison Formation, Dinosaur Quarry Quadrangle, Utah, Sue Ann Bilbey May 1973

Petrology And Geochemistry Of The Morrison Formation, Dinosaur Quarry Quadrangle, Utah, Sue Ann Bilbey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mineralogical and petrographic analyses of the upper Jurassic - lower Cretaceous units in the vicinity of the Dinosaur National Monument quarry near Jensen, Utah, have elucidated their characteristics and the locations of formational boundaries. The lower part of the Morrison Formation is distinguished by a decreased amount of illite and an increased amount of kaolinite. In contrast, the underlying Curtis Formation contains an approximately equal mixture of illite and kaolinite. The lower Salt Wash Member and the upper Brushy Basin Member of the Morrison are both lithologically and mineralogically identifiable in this area. Above the boundary between the two, kaolinite …


Structural Geology Of The Northern Part Of Clarkston Mountain, Malad Range, Utah-Idaho, Steven Mark Burton May 1973

Structural Geology Of The Northern Part Of Clarkston Mountain, Malad Range, Utah-Idaho, Steven Mark Burton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The northern part of Clarkston Mountain, in northern Utah and southern Idaho, is located about 23 miles northwest of Logan, Utah. It extends across the Malad Range from Malad Valley on the west to Cache Valley on the east. The mapped area measures 4.8 miles in the north-south direction and 6.8 miles in the east-west direction.

The Brigham Formation of Cambrian age is the oldest exposed stratigraphic unit. It consists mainly of quartzite. Younger Cambrian units include the Langston, Ute, Blacksmith, Bloomington, Nounan, and St. Charles Formations. The Garden City Formation of Ordovician age is the youngest Paleozoic unit. The …


An Intensive Edaphological Characterization Of The Soils Of Malambito Experimental Station And Its Implications In Future Agricultural Research, William L. Rubink May 1973

An Intensive Edaphological Characterization Of The Soils Of Malambito Experimental Station And Its Implications In Future Agricultural Research, William L. Rubink

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Malambito Experiment Station, in the Atlántico III project area, Department of Atlántico, Colombia, had almost no quantitative edaphological data on which to base agricultural research. Unexplainably low general yields as well as problem areas of deficient plant growth only confounded the results of field plot experiments. Intensive soil sampling and subsequent measurements of pH, ECe of the saturation extract, and the four major cations disproved the previous suggestions that the crop growth problems were related to saline, sodic, or degraded soil conditions. The Ca/Mg+K+Na ratio, although significant when correlated with plant height, was sufficient explanation for only a small …


A Measure Of The Amount Of Phosphate Adsorption And The Rate Of Release Of Indigenous Phosphate From A Desert Soil, Robert Lindsey Evans May 1973

A Measure Of The Amount Of Phosphate Adsorption And The Rate Of Release Of Indigenous Phosphate From A Desert Soil, Robert Lindsey Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The capacity of a calcareous desert soil, Thiokol silt loam, to retain natural, as well as added, orthophosphate-P was measured by equilibrium adsorption employing a batch technique and evaluated using the two-slope Langmuir adsorption isotherm. From these data, corrected to account for indigenous soil P, a hypothesis was formulated as to the nature of retention of P by the soil, including the identification of two interfacial reactions involving P, and a value calculated for the adsorption maximum as defined by the Langmuir isotherm equation for P with soil at each of two soil depths and three constant temperatures within the …


Mineral And Chemical Content Of The Deep-Water Sediment Sequences Of Bear Lake, Utah-Idaho, James C. Biesinger May 1973

Mineral And Chemical Content Of The Deep-Water Sediment Sequences Of Bear Lake, Utah-Idaho, James C. Biesinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-five piston cores 6 to 12 feet long were obtained from the deepwater sediments of Bear Lake, Utah-Idaho. Analyses of these cores revealed that the deep-water sediments of the lake are divided into two major sequences: a younger sequence rich in carbonate minerals, here called the carbonate sequence, and an older sequence rich in silicate minerals, referred to in this paper as the silt sequence. The carbonate sequence is composed of clay-sized quartz, aragonite, calcite, dolomite, montmorillonite, illite, kaolinite, chlorite, and amorphous material. The silt sequence consists of both silt- sized and claysized particles of quartz, calcite, dolomite, montmorillonite, illite, …


Groundwater Levels In Nebraska, 1972, M.J. Ellis May 1973

Groundwater Levels In Nebraska, 1972, M.J. Ellis

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


A Study Of Trace Metal Concentrations In Two Species Of Mytilus Along The Pacific Coast Of The United States., George Harry Fullas Apr 1973

A Study Of Trace Metal Concentrations In Two Species Of Mytilus Along The Pacific Coast Of The United States., George Harry Fullas

Earth and Planetary Sciences ETDs

An investigation of iron, zinc, copper, and cadmium concentrations in Mytilus californianus and Mytilus edulis was conducted on specimens collected along the west coast of the United States. Animals and sea water were collected at six different areas and analyzed using an Atomic Absorption Spectrophotometer. Trace metal concentrations in the animals were influenced by the collection conditions of age, species, temperature, pollution, and metal relationships. Younger animals, of both species, contained higher concentrations of all the metals. Larger, or older animals, contained the smallest metal concentrations. Copper concentrations in the animals were higher in sea water with high copper content. …


Little Drum Mountains, An Early Tertiary Shoshonitic Volcanic Center In Millard County, Utah, Stephen H. Leedom Apr 1973

Little Drum Mountains, An Early Tertiary Shoshonitic Volcanic Center In Millard County, Utah, Stephen H. Leedom

Theses and Dissertations

The Little Drum Mountains represent a deeply eroded Eocene-Oligocene volcano, consisting of a vent complex which erupted mafic flows and flow breccias, accompanied by lahars. Flows are dominated by members of the shoshonite suite and contain up to 3.95 percent K2O, mainly occult in K-rich glass, with K2O/Na2O ratios greater than 1.0. In a few interbedded flows, apparently of the calc-alkaline series, pyroxene with varying amounts of plagioclase in a fine-grained groundmass of plagioclase, mafic minerals, and interstitial glass. An ash-flow tuff of the Oligocene Needles Range Formation unconformably overlies the volcanic sequence. Contemporaneous …


Implications Of Photogeologic Linears In The South Long Lake Area, Alpena And Presque Isle Counties, Michigan, Richard E. Kimmel Apr 1973

Implications Of Photogeologic Linears In The South Long Lake Area, Alpena And Presque Isle Counties, Michigan, Richard E. Kimmel

Masters Theses

There are numerous linear features in Alpena and Presque Isle Counties, Michigan, which are generally visible on aerial photographs. These photolinears trend in two general directions, northeast-southwest and northwest-southeast. These two sets are perpendicular to each other, and represent vector means of two fracture sets.

The development of the photolinears began in Early Devonian. Throughout its history, ground water flowed along underground channels connecting fracture intersections. This underground drainage network is responsible for many of the photolinears. Some of the photolinears can be attributed tb Early Devonian ground water activity and subsequent collapse of the Salina Salt basin, and some …


A Rare Earth Element Study Of Some Basalts From The Modoc Quadrangle, California, Charles Stewart Colodby Apr 1973

A Rare Earth Element Study Of Some Basalts From The Modoc Quadrangle, California, Charles Stewart Colodby

Senior Honors Papers / Undergraduate Theses

No abstract provided.


Response To Alloformitarianism, Richard G. Hodgson Mar 1973

Response To Alloformitarianism, Richard G. Hodgson

Pro Rege

No abstract provided.


The Characteristics And Genesis Of Stone Stripes In North Central Oregon, John Baine Pyrch Feb 1973

The Characteristics And Genesis Of Stone Stripes In North Central Oregon, John Baine Pyrch

Dissertations and Theses

Stone stripes are linear accumulations of rock debris separated by finer material and oriented down the steepest available slope. In north central Oregon, the stone stripes are composed of basalt fragments and occur where the soil mantle averages less than 1 m in depth. They are best developed in areas of higher elevation, usually from about 900 to 1100 m, and are most prominent on convex to straight slopes of 15 to 30 degrees. The stripes vary from a few meters to over 150 in length, and their widths range from 0.3 to over 3 m. The depth of the …


Demographic Studies Of Sagebrush Insects As Functions Of Various Environmental Factors, T. H. Hsiao, R. L. Kirkland Jan 1973

Demographic Studies Of Sagebrush Insects As Functions Of Various Environmental Factors, T. H. Hsiao, R. L. Kirkland

Memorandum

No abstract provided.


Distribution Of Mictroorganisms In Desert Soil, A.T. Vollmer, F. Au, S.A. Bamberg Jan 1973

Distribution Of Mictroorganisms In Desert Soil, A.T. Vollmer, F. Au, S.A. Bamberg

Memorandum

No abstract provided.


Terrestrial Models: Soil Processes (Versions I, Ii, Iii), J. Radford Jan 1973

Terrestrial Models: Soil Processes (Versions I, Ii, Iii), J. Radford

Memorandum

No abstract provided.


Gaseous Losses Of Nitrogen From The Soil Of Semi-Arid Regions, T.C. Tucker, R.L. Westerman Jan 1973

Gaseous Losses Of Nitrogen From The Soil Of Semi-Arid Regions, T.C. Tucker, R.L. Westerman

Memorandum

No abstract provided.


Population Studies Of The Desert Cottontail (Sylvilagus Auduboni) And Black-Tailed Jackrabbit (Lepus Californicus) In The Sonoran Desert, C.R. Hungerford, C.H. Lowe, R.L. Madsen Jan 1973

Population Studies Of The Desert Cottontail (Sylvilagus Auduboni) And Black-Tailed Jackrabbit (Lepus Californicus) In The Sonoran Desert, C.R. Hungerford, C.H. Lowe, R.L. Madsen

Memorandum

No abstract provided.


The Role Of Algae In Crust Formation And Nitrogen Cycling In Desert Soils, R I. Lynn, R E. Cameron Jan 1973

The Role Of Algae In Crust Formation And Nitrogen Cycling In Desert Soils, R I. Lynn, R E. Cameron

Memorandum

No abstract provided.


Special Purpose Models, D. Wilkin Jan 1973

Special Purpose Models, D. Wilkin

Memorandum

No abstract provided.


Evaluation Of Critical Soil Properties Needed To Predict Soil Water Flow Under Desert Conditions, J Letey Jr, G R. Mehuys, L V. Weeks Jan 1973

Evaluation Of Critical Soil Properties Needed To Predict Soil Water Flow Under Desert Conditions, J Letey Jr, G R. Mehuys, L V. Weeks

Memorandum

No abstract provided.


Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan Jan 1973

Broad Spectrum Microwave Systems For Remotely Measuring Soil Moisture Content, W. P. Waite, K. R. Cook, B. B. Bryan

Arkansas Water Resources Center Technical Reports

A theoretical and experimental study of the microwave reflectivity of soils with varying moisture content was conducted. A system was developed to measure reflectivity over a continuous frequency range of 4 to 26.5 GHz, at incidence angles from 10° to 70°, and with both horizontal and vertical polarization. The measurements were found to be extremely accurate for smooth homogeneous surfaces, however, the effects of surface roughness were found to be more severe than predicted due to the discontinuous nature of naturally occurring rough surfaces. An algorithm was developed which used the frequency dependence of the reflectivity to estimate the effective …