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Full-Text Articles in Soil Science

Effects Of Polyacrylamide On Rangeland Soils And Plants, Saud Leily R. Al-Rowaily May 1992

Effects Of Polyacrylamide On Rangeland Soils And Plants, Saud Leily R. Al-Rowaily

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine the effects of two forms of polyacrylamide (PAM) conditioners (Cross-linked and Non-cross-linked PAM) on evaporation, saturated hydraulic conductivity, water retention, crust and crack formation of soils, seed germination, and seedling and tubeling growth.

The two PAM conditioners, 0.2% concentration by weight, were mixed with seven soils of different textures (sandy loam, silt, silty clay loam, silt loam, fine sand, medium sand, and coarse sand) to investigate the effects on evaporation, saturated hydraulic conductivity, and water retention. Soil samples of different textures were brought to field capacity and placed in a growth chamber …


Soil Temperature Influence On Water Use And Yield Under Variable Irrigation, Jon M. Wraith May 1989

Soil Temperature Influence On Water Use And Yield Under Variable Irrigation, Jon M. Wraith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need for efficient use of water resources has increased the importance of optimum soil water usage in agricultural systems. Soil temperature has been shown to be important in influencing the early development of many plant species. Many agricultural regions have suboptimal soil temperature regimes for plant growth, and some cultural practices have been shown to reduce near-surface soil temperatures. The seasonal influence of soil temperature on soil water extraction and aboveground and belowground plant growth under variable irrigation was investigated at the USU Greenville Farm in Logan, UT. Soil surface mulches and buried heat cables were used to modify …


Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson May 1989

Root Exploitation Of Fertile Soil Microsites, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root exploitation of enriched soil microsites was examined for the tussock grasses Agropyron desertorum and Agropyron spicatum and the shrub Artemisia tridentata. Two mechanisms of exploitation of the microsites were examined: root proliferation and changes in nutrient uptake capacity. One day after nutrient solution was applied to small soil patches, the mean relative growth rate of Agropyron desertorum roots in enriched patches was two to four times greater than for roots of the same plants in soil patches treated with distilled water. This rapid and striking root proliferation occurred in response to N-P-K enrichment as well as to P or …


Boron Composition Of Alfalfa In Utah As Related To Soils And Irrigation Waters, Robert N. Radtke Jr. May 1986

Boron Composition Of Alfalfa In Utah As Related To Soils And Irrigation Waters, Robert N. Radtke Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Eighteen field plots at 15 locations were selected throughout the state to evaluate the status of the boron content in irrigation waters, soils, and alfalfa (Medicago sativa) plant tissue under irrigated conditions.

No boron deficiency symptoms were observed in any of the alfalfa plants at any of these locations, nor were any of the plant tissue boron levels inadequate. Only two locations were found in which the alfalfa plants exibited toxicity symptoms. These locations were along the Indian and Antelope Creeks in Duchesne County which contain high boron levels in the water. All the alfalfa and soil tested …


Chemical Weathering Of Pyrite In Soils, Aaron D. Brown May 1985

Chemical Weathering Of Pyrite In Soils, Aaron D. Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The products of pyrite oxidation, including solution phase Fe2+, Fe3+, S2O32-, S4O62-, SO32- and SO42- and solid phase Fe(OH)3, were measured under controlled conditions in order to investigate the behavior of pyrite in calcareous and alkaline soils.

The distribution of sulfur oxidation products is pH dependent and can be interpreted in terms of metastable equilibrium among thiosulfate, disulfane disulfonate and sulfite. Thiosulfate and sulfite predominate in the pH range greater than about pH 7 or 8. Sulfane disulfonates are more …


Genesis Of A Vertisol And An Associated Palexeroll In Northern Utah, Robert C. Graham May 1982

Genesis Of A Vertisol And An Associated Palexeroll In Northern Utah, Robert C. Graham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The genetic relationship between a Vertisol and an associated Mollisol with an argillic horizon was studied. These soils are taxadjuncts of the Hawkins and Ostler series, respectively. They occur in the Wasatch Mountains of northern Utah and have similar parent materials, altitudes, and slope percentages. Ostler soils have a dense cover of Gambel oak (Quercus gambelii) and occur preferentially on north aspects. Mule's ear (Wyethia amplexicaulis) is the dominant vegetation on Hawkins soils, which are most frequent on south aspects. Erosion is prevalent on Hawkins soils because the mule's ear does not adequately cover the soil …


Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani May 1980

Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Characteristics and genesis of five pedons representing some of the soils of the central Alborz mountain northeast of Tehran were investigated. The present climate of the area is similar to the Mediterranean climate. The parent materials for the soils under study have apparently been derived from the Ecocene Alborz Green Beds (a thinly bedded light green mudstone), the Pliocene Hezardareh Formation (a poorly-cemented conglomerate) and Recent alluvium and colluvium. Pedons 2 and 4 are located at lower elevations (plain and river terraces) on 1 to 2 percent slopes. Pedons 3 and 5 are located at higher elevations (hills that surround …


Turbidity - Suspended Sediment Relations In A Subalpine Watershed, Thomas A. Holstrom May 1979

Turbidity - Suspended Sediment Relations In A Subalpine Watershed, Thomas A. Holstrom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of particle size distribution of suspended sediment vii upon a turbidity reading at a known concentration has been relatively quantified for stream bank materials on the Moccasin Basin - North Fork Fish Creek (MB-NFFC) Watershed, located in northwestern Wyoming. As expected, an increase in the median particle size in suspension results in a decrease of turbidity at a given concentration. The relationship derived correlates the particle size distribution of a chemically dispersed stream-bank material sample, with the Coefficient of Fineness for a mechanically dispersed portion of the sample.


Vertical Mesoscale Water Vapor Flux In An Irrigated Valley, Esmaiel Malek May 1977

Vertical Mesoscale Water Vapor Flux In An Irrigated Valley, Esmaiel Malek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To obtain the profiles of dry bulb and wet bulb temperature, specific humidity, q, and air density, ρ, to a height of 200 meters above the ground, a precise lightweight thermocouple psychrometer was designed. To lift the thermocouple psychrometer and the attached wires in obtaining the ρq profiles, a rigid polyethylene balloon augmented with 5.5-feet outdoor or 100-g meteorological balloons were used. Using the height dependent eddy exchange coefficient and a one-dimensional time-dependent profile model, the nighttime variations of ρq as a function of height were predicted and compared with observed values. It was found that the general shape of …


Effect Of Drilling Fluid Components And Mixtures On Plants And Soils, Parvin Pesaran (Djavan) May 1977

Effect Of Drilling Fluid Components And Mixtures On Plants And Soils, Parvin Pesaran (Djavan)

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The concern about the environment has required that the effects of drilling fluids (muds) on surrounding areas be known. This study was initiated to investigate the effects of various muds on plant growth and on soils.

In preliminary studies in Phase I (31 individual mud components), it was concluded that the obvious dominant effects on plant growth of detrimental drilling fluid components included excess soluble salts, excess exchangeable sodium percentage, possibly a high pH in some mixtures, and undesirable physical conditions. The latter resulted from the sodium and/or starch, gums, and bentonite.

Phase II, the second year's study of the …


Seasonal Course Of Root Respiration In Atriplex Confertifolia, Richard S. Holthausen May 1977

Seasonal Course Of Root Respiration In Atriplex Confertifolia, Richard S. Holthausen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root respiratory response of mature Atriplex confertifolia plants growing in established communities was measured during two growing seasons using freshly excised root segments and gas chromatography techniques. Respiratory response at fixed test temperatures changed significantly during the growing season, and this pattern of respiratory adjustment varied for root segments located at different depths in the soil profile. Respiration measured at a constant test temperature was highest during early sumner, and declined to minimum values in late summer and fall. Root segments taken from the top 30 cm of the soil profile displayed peak activity several weeks before root segments from …


Phosphorus Availability As Indicated By Alfalfa Response To Applied Phosphorus On Soils With Low Soil-Test Values, Ibrahim Odeh Ghawi May 1977

Phosphorus Availability As Indicated By Alfalfa Response To Applied Phosphorus On Soils With Low Soil-Test Values, Ibrahim Odeh Ghawi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A field experiment was conducted at two locations in Utah, one at Erda in Tooele County and the other at Minersville in Beaver County. Each experiment was designed as a randomized block design with five treatments and four replication s for each treatment. The test crop was alfalfa. Three cuttings were taken from each location to estimate the yield. Soil samples from the first 12 inches and subsoil samples from 12-24 inches were taken to determine the available NaHCO3-P in the soils. Plant samples were taken to determine the P content of the crop. The results showed that …


The Evaluation Of A Computer Model To Predict The Effects Of Salinity On Crop Growth, James K. Wolf May 1977

The Evaluation Of A Computer Model To Predict The Effects Of Salinity On Crop Growth, James K. Wolf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A model was developed to predict the effects of soil salinity on crop growth. The model makes three major assumptions: 1) Relative yield for a growing season is directly related to the ratio of actual and potential transpiration. 2) Water uptake by plants is in response to the water potential gradient between the plant roots and the surrounding soil. 3) The effects of the soil salinity on crop growth is solely due to the affect of osmotic potential in decreasing the water potential. Minor assumptions also included are concerned with the plant growth cover, plant root growth, and the separation …


Some Aspects Of The Salinity Of Mancos Shale And Mancos Derived Soils, James C. Whitmore May 1976

Some Aspects Of The Salinity Of Mancos Shale And Mancos Derived Soils, James C. Whitmore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Initial studies to determine the thermodynamic solubility product (Ksp) of gypsum and CaCO3 were conducted. The influence of different electrolyte salts at different concentrations upon the solubility of gypsum and CaCO3 was then tested. Analytical data was utilized in conjunction with a computer to calculate the activity of CaCO3 and gypsum, the ion pair concentration and the solubility product. Indifferent salts increased the solubility of gypsum and CaCO3, and salts with a common ion decreased the solubility of gypsum and CaCO3.

Lithium was found to be the dominant monovalent cation present …


Nitrogen Fertilization Studies In Dryland Winter Wheat And Potential Nitrogen Losses From The Soil At The Blue Creek Experimental Station In Northern Utah, Subhawat Intalap May 1976

Nitrogen Fertilization Studies In Dryland Winter Wheat And Potential Nitrogen Losses From The Soil At The Blue Creek Experimental Station In Northern Utah, Subhawat Intalap

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study compared the effects of nitrogen sources on the available inorganic soil nitrogen, nitrogen movement, nitrogen losses, and wheat yields when nitrogen fertilizers were applied to soil planted to dryland winter wheat at the Blue Creek Experimental Station in northern Utah.

In the fall 1973 soil samplings, the fertilizers producing the largest mineral nitrogen contents in the 0-30 cm soil depths were ammonium nitrate >ammonium sulfate > S-coated urea, when they were broadcast at the practical rate of 56 kg N/ha. There was no increase in the mineral nitrogen at the dee per depths in the fall or at any …


The Accuracy Of Soil Mapping Units Of Certain Pachic And Cumulic Soils In Northern Utah, Behjat Badamchian May 1976

The Accuracy Of Soil Mapping Units Of Certain Pachic And Cumulic Soils In Northern Utah, Behjat Badamchian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to determine the accuracy of mapping of pachic and cumulic soils in Cache County. The soil maps that were used for this study as the basemap were the Atlas sheets of the published soil survey of Cache County.

Five map units from Mendou, Nebeker, Avon, Hendricks and Winn which include almost 52 percent of the pachic and cumulic soils in the survey area were selected for this study. These five soils cover large areas when compared to other soil series and they are distributed throughout the county. All these map units were recognized as …


Albedo Of The Earth's Surface -- A Comparison Of Measurements Taken On The Ground And From Flying Platforms, Frank D. Eaton May 1976

Albedo Of The Earth's Surface -- A Comparison Of Measurements Taken On The Ground And From Flying Platforms, Frank D. Eaton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The main objectives of this study were to develop the intricacies of reflected solar radiation from different natural surfaces and to show comparisons between values sensed in space of emergent radiation to ground values obtained from accounting for anisotropic reflection and estimating the effect of the intervening atmosphere. Thus, this study demonstrated that a prior knowledge of the angular distribution of reflected radiation allows determining the true hemispherical reflected radiation from a narrow field of view instrument such as found on a flying platform. Measurements for determining the indicatrices were made from a tower-mounted Nimbus MRIR and, in one case, …


A Model For Designing Surface Drainage Systems In Nearly Level Agricultural Lands, Rafael Maria Rojas May 1976

A Model For Designing Surface Drainage Systems In Nearly Level Agricultural Lands, Rafael Maria Rojas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The increasing demand for reclamation of periodically waterlogged nearly level agricultural lands in humid tropical areas and the hazard of soil deterioration and soil moisture balance disturbances by current land forming methods suggests the need for investigations of new surface drainage design procedures. This report presents a rainfall-runoff model for simulating hydrographs from ungaged agricultural plots. The model is based on routing procedures and utilizes common soil and hydrologic data. Tests made with several small agricultural water-sheds indicate that the model could be a useful tool in simulating surface drainage design.

Input data for the model consists of (a) rainfall …


Irrigation Scheduling Program For Sugarcane, Terence L. Pearse May 1976

Irrigation Scheduling Program For Sugarcane, Terence L. Pearse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An estimate of potential evapotranspiration is acquired to implement an irrigation scheduling program. Four equations, which estimate potential evapotranspiration (evaporation) were evaluated for prediction of Class "A" Pan evaporation. The equations used were Penman's combination equation, the Jensen-Haise temperature and radiation equation, and two of the Christiansen-Hargreaves polynomial regression type equations. Measured and calculated radiation was used together with two values of albedo. Four years of daily climate data from Rhodesia was evaluated by general linear regression methods.

Despite the significant variations between the four annual regression lines of each equation, the use of confidence intervals indicate that the Penman …


Modeling Spring Wheat Production As Influenced By Climate And Irrigation, V. Philip Rasmussen Jr. May 1976

Modeling Spring Wheat Production As Influenced By Climate And Irrigation, V. Philip Rasmussen Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A model has been developed that predicts spring wheat grain and dry matter yield. Preliminary tests show very favorable results when predicting grain yield in two different climatic regimes, one being a dryland and another being an irrigated area. The strengths of the model lie in its simplicity, relatively available input data, and low computer processing time cost. Weakness of the model stem from the assumptions that allow its simplicity. The basic assumption in the model is that grain and dry matter yield can be related to the ratio of actual to potential transpiration, computed for each of five phenological …


A Model To Predict The Effect Of Salinity On Crop Growth, Stuart W. Childs May 1975

A Model To Predict The Effect Of Salinity On Crop Growth, Stuart W. Childs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A model is developed to predict the effects of soil salinity on crop growth. As an outgrowth and extension of the modelling efforts of Nimah and Hanks (1973a) and Gupta (1972), this model makes these principal assumptions in order to arrive at a quantitative relationship: 1) relative yield for a growing season is directly related to the ratio of actual and potential transpiration. 2) Water uptake by plants is in response to the water potential gradient between the plant at the soil surface and the soil surrounding the plant roots. 3) the effect of salinity on crop growth is solely …


Distribution Of Available Phosphorus In The Subsoil Of Selected Pedons Of The Warm Springs Series, Duane Altman Lammers May 1975

Distribution Of Available Phosphorus In The Subsoil Of Selected Pedons Of The Warm Springs Series, Duane Altman Lammers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Warm Springs soil series which contained variable amounts of subsoil available (sodium bicarbonate extractable) phosphorus was studied to explain the variability and distribution of the NaHCO3-P in the subsoil. Four pedons ranging in subsoil NaHCO3-P from less than 10 ppm to greater than 30 ppm were selected in an area of less than 200 ha located on a nearly level, low lake terrace east of the Great Salt Lake in Weber County, Utah.

The morphology of each pedon was described in the field and samples collected from each genetic horizon or contrasting layer. Each soil …


Effect Of Drilling Fluid Components And Mixtures On Plants And Soils, Shahnaz Honarvar (Asad Sangabi) May 1975

Effect Of Drilling Fluid Components And Mixtures On Plants And Soils, Shahnaz Honarvar (Asad Sangabi)

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Using greenhouse pot techniques, 32 drilling mud components were tested to see if, at a high rate of addition, they reduced plant growth. Green beans and sweet corn were the test plants. The excellent black, silt loam, slightly acidic, uncultivated Dagor soil (Cumulic Haploxeroll) was used for most tests. Rates used were considered to be abnormal level (high rate) and usual (low rate) amounts that might be added in commonly used drilling muds.

Drilling mud components that caused no observable or statistically significant reductions of plant yield are the following: Super Visbestos, (Asbestos), asphalt, Ben-Ex (a vinyl acetate and maleic …


Evaluating The Availability Of Organic Nitrogen In Soils, Saleh M. Romaih May 1975

Evaluating The Availability Of Organic Nitrogen In Soils, Saleh M. Romaih

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The main objective of this study was to evaluate the organic N in silty clay loam soil as an indicator of soil fertility. The incubation method was used in this study. The NO3 -N, the total N percent, and the organic matter were determined. The soil which was used in this study came from Evans Research Farm. The samples were taken from two different N experiments which were adjacent to each other. The soil samples were taken in October-November, 1973, after the crop had been harvested. These two experiments had different cropping histories.

The results of the first experiment …


Residual Nitrogen As It Affects Soil Fertility Under Irrigated Agriculture In A Tropical Wet-Dry Climate, Don Carlos Kidman May 1975

Residual Nitrogen As It Affects Soil Fertility Under Irrigated Agriculture In A Tropical Wet-Dry Climate, Don Carlos Kidman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the Zapotitan Valley near San Andres, El Salvador, Central America, an experiment was conducted to determine the availability of residual soil N to corn grown during the rainy season. This was an extension of an experiment conducted during the preceding dry season. The variables of the dry season experiment were irrigation method, crop, and rate of fertilizer N application. Soil NO3-N and NH4-N were determined by soil sample analysis to a soil depth of 120 cm by 30 cm depth increments. The samples were taken at the end of the dry season experiment and again …


The Contribution Of Subsoil Phosphorus To The Nutrition Of Alfalfa As Influenced By Soil Temperature, Reuel E. Lamborn May 1975

The Contribution Of Subsoil Phosphorus To The Nutrition Of Alfalfa As Influenced By Soil Temperature, Reuel E. Lamborn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High bicarbonate-soluble phosphorus (P) in some Utah subsoils may affect the validity of fertilizer recommendations based on plow layer samples. The primary objective of this experiment was to determine the proportion of plant P derived from subsoils at typical Utah soil P levels and soil temperatures.

A calcareous soil very low in bicarbonate-soluble P was treated with various amounts of P and packed into deep pots to provide 24 centimeters of "topsoil" and 27 centimeters of "subsoil". Water baths in a growth chamber were used to control soil temperatures at 14 centigrade and 20 centigrade. Light, air temperature and humidity …


Determination Of Crop Production Functions As Related To Soil Moisture And Nitrogen, James W. Bauder May 1974

Determination Of Crop Production Functions As Related To Soil Moisture And Nitrogen, James W. Bauder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil moisture and nitrogen are often the primary controlling factors of crop production. Production functions are valuable in describing crop responses to such controlling factors. Such functions are also needed for determining the economic reliability of crop production.

Soil moisture and nitrogen fertilizer were maintained at various levels to determine the response of field corn to these controlling factors. A conventional split plot design, a continuous function experimental design, and a confined barrel plot design were used to obtain data for determining production functions.

The complete factorial, conventional split plot data was successfully used to generate reliable production functions in …


Characteristics And Genesis Of The Parleys And Mendon Soils Series In Northern Utah, Khalid I. Al-Amin May 1974

Characteristics And Genesis Of The Parleys And Mendon Soils Series In Northern Utah, Khalid I. Al-Amin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study was designed to test the genetic theory of soil development of two soils derived from different geological material, but developed under conditions of similar climate, topography, biological activity, and age. An attempt was made to relate the soils characteristics to their present classification. Parleys and Mendon series which developed from Bonneville and Salt Lake Formation, respectively, were selected for that purpose. Along the east side of Cache valley, two pedons representing each of the studied series were selected to have similar soil formers except for their parent material.

Evidently, these studied soils have been developed from different heterogenous …


A Study Of The Radiation Quality Under Plant Canopies In The Wave Range 0.4 To 2.5 Microns, Nolasco G. Baldazo May 1974

A Study Of The Radiation Quality Under Plant Canopies In The Wave Range 0.4 To 2.5 Microns, Nolasco G. Baldazo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spectral distribution of the global radiation from 0.4 to 2.5 microns penetrating deciduous and coniferous canopies were measured during clear days between 10 a.m. and 2 p.m. using a double-quartz monochromator.

In the visible region (0.4 to 0.7 micron) the average relative spectral transmissions under both canopies are about one percent beginning at 0.4 micron and decreasing to about half a percent at 0.67 micron. There is only a small peak in the green (0.55 micron) transmission under deciduous stands while there is none under coniferous canopies. The slightly higher transmission in the blue (0.4 micron) is attributed to …


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 …