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Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker May 2024

Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

There are many sources that farmers utilize to determine fertilizer needs for crops such as private and public labs, crop advisors, and fertilizer dealers. In many cases, these sources provide recommendations for a specific crop that can vary greatly, which can lead to large differences in cost. An experiment was established in 2021 with 12 sites across the state of Utah in alfalfa, small grains, and corn to test and compare fertilizer recommendations from five labs. The recommendations tested were from two public labs (Utah State University and the University of Idaho) and three commercial labs located in the Western …


Nutrient Uptake And Water Quality In Great Salt Lake Wetland Impoundments, Rachel L. Buck May 2022

Nutrient Uptake And Water Quality In Great Salt Lake Wetland Impoundments, Rachel L. Buck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Great Salt Lake (GSL) is the largest inland body of water on the Pacific flyway, a major pathway for migratory birds in the Americas that extends from Alaska to Patagonia. The lake is surrounded by approximately 360,000 acres of wetlands, providing critical food, shelter, cover, nesting areas, and protection to between 4–6 million birds that visit each year. Impounded wetlands were created as part of the GSL ecosystem to support waterfowl habitat. These large, shallow, submergent wetlands are diked to control water levels to sustain aquatic plants which are an important food source. Besides providing critical habitat, these impoundments …


4r Nitrogen And Water Optimization Combinations For Intermountain West Field Crops, Tina Sullivan May 2022

4r Nitrogen And Water Optimization Combinations For Intermountain West Field Crops, Tina Sullivan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The concept of 4R (right source, rate, placement, and timing) management needs little introduction due to the surplus of nutrient studies in the literature for most cultivated crops. However, few studies have looked at these practices in the Intermountain West with nitrogen use, and fewer looked at 4R irrigation management. A survey was conducted to explore the interactions of nitrogen and irrigation management, test sensitivity to supply and price changes of nitrogen and irrigation for Utah and Idaho growers of small grains, corn, and potatoes, and determine the current adoption of precision agriculture options and identify the opportunities to improve. …


Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi Aug 2021

Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change is rapidly warming the Arctic, especially at lower latitudes. Warmer temperatures and earlier springs are altering the timing of plants and animals, especially for long-distance migratory herbivores. Changes in the timing of both plants and herbivores have the potential to impact plant productivity and nutrient cycling, while also altering plant community diversity and composition.

In chapter 2, I conducted a field experiment to investigate how earlier growing seasons and differences in arrival times of migratory geese influence physical traits of sedge forage species. I found that both an earlier growing season and late grazing by geese had similar …


The Fate And Cycling Of Nitrogen, Phosphorous, And Trace Heavy Metals In Beaver-Altered Headwater Streams, Desneiges S. Murray May 2021

The Fate And Cycling Of Nitrogen, Phosphorous, And Trace Heavy Metals In Beaver-Altered Headwater Streams, Desneiges S. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human land-use can increase the amount of non-point source (NPS) pollution in a stream, negatively affecting ecosystem health and beneficial services provided by an ecosystem. Unfortunately, NPS pollution remains high in many waterbodies. Beaver dams may be a passive, cost-effective strategy for removing NPS pollution in headwater streams because beaver dams slow stream flow and collect sediments. Impounded sediments can change how nutrients and pollutants are cycled in a stream through multiple pathways. In the first part of our study, we investigated whether beaver activity can reduce nitrogen, phosphorous and heavy metals from otherwise traveling downstream. Results suggest beaver ponds …


Investigations Of Substrate Reduction By Nitrogenase: Light Powered Substrate Reduction By A Cds:Femoco System And Understanding Dinitrogen Inhibition Of Electron Transfer, Hayden Kallas May 2021

Investigations Of Substrate Reduction By Nitrogenase: Light Powered Substrate Reduction By A Cds:Femoco System And Understanding Dinitrogen Inhibition Of Electron Transfer, Hayden Kallas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen fixation is a key step of the nitrogen cycle which makes biologically inert N2 gas available for organisms to use in the form of ammonia. Nitrogen fixing microorganisms all contain the same enzyme called nitrogenase which catalyzes the six electron transfers to N2 required for conversion into ammonia. Nitrogenase is a two-component enzyme that contains a cofactor composed of iron and sulfur as well as heavier metals whose identity can be molybdenum, vanadium, or an additional iron atom depending on the variant. The two components of nitrogenase are the MFe protein and the Fe protein. The Fe …


Enhancing The Production And Sustainability Of Pasture-Fed Beef Using Non-Traditional Legume Forages, Andrea I. Bolletta Aug 2020

Enhancing The Production And Sustainability Of Pasture-Fed Beef Using Non-Traditional Legume Forages, Andrea I. Bolletta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite the increasing worldwide demand for beef as a protein source, consumers are concerned about the sustainability of ruminant production systems. Their main concerns are animal welfare for feedlot-fed animals, greenhouse gas (GHG) emissions, global warming and worker safety. Traditional feedlot-based beef production systems have been associated with locally greater levels of soil, water and air contamination, as well as the overuse of antibiotics and growth hormones. The use of legume pastures such as cicer milkvetch (CMV) and birdsfoot trefoil (BFT), which fix their own nitrogen (N) and often contain beneficial secondary compounds such as tannins and provide for rapid …


Effect Of Tannin-Containing Legume Hays On Enteric Methane Emissions And Nitrogen Partitioning In Beef Cattle, Elizabeth K. Stewart Aug 2018

Effect Of Tannin-Containing Legume Hays On Enteric Methane Emissions And Nitrogen Partitioning In Beef Cattle, Elizabeth K. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cattle are responsible for greenhouse gas emissions such as carbon dioxide, methane and nitrous oxide. In particular, the cow-calf phase of production accounts for approximately 80 percent of the total beef production system greenhouse gas emissions. Tannins are chemical compounds found in certain forages and they have the potential to help reduce these negative environmental impacts. Thus, given that the cow-calf phase often relies on feeding hay, feeding tannin-containing hays may represent a significant mitigation practice.

With my MS program, I sought to explore whether tannin-containing hays fed to mother cows and heifers influence methane and nitrogen emissions relative to …


Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar Dec 2017

Nitrogen Availability And Use Efficiency In Corn Treated With Contrasting Nitrogen Sources, Avneet Kakkar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plant-soil nitrogen cycle plays a significant role in allocation of available N to plants, and improved understanding of N cycling helps sustainably increase fertilizer use efficiency. There are various processes (nitrogen mineralization and nitrification) involved in the availability and mobility of nitrogen in the soil. The primary objective of this study was to determine the NUE under contrasting nitrogen treatments over a period of five years. Additionally, we examined the effect of different N treatments on N mineralization and nitrification in conventional and organic farming systems.

This project was funded by Agriculture and Food Research Initiative Competitive Grants Program …


Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore May 2013

Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our forests provide us with a variety of services from clean water, forest products and wildlife habitat to the lesser known functions of nutrient cycling and carbon
sequestration. This research helps to demonstrate the extent of some of these services in a heavily disturbed southern Appalachian spruce-fir forest within Great Smoky Mountain National Park, the most heavily visited National Park in the United States. Following a catastrophic infestation of the non-native balsam wooly adelgid, the future of this forest was unknown, causing some to speculate about the future of this sensitive forest type. Though predictions about this forest’s future varied …


15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein May 2011

15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lakes have historically been overlooked as important nutrient processors within their watersheds. In general ecologists have focused on streams as zones of uptake and transformation, while viewing lakes as simple nutrient traps. However, recent research has highlighted the large influence that lakes may have on water chemistry within their watersheds. Within the field of limnology, researchers have traditionally focused on the pelagic zone for in-lake production. Further research in shallow lakes has highlighted the role benthic production within the littoral zone plays in the lake ecosystem. The greater influence of lakes is highlighted when comparing watersheds containing lakes with watersheds …


An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds Dec 2010

An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species diversity achieved by adding novel functional groups (warm-season grasses and non-leguminous forbs) to pasture land, along with traditional grasses and legumes, could aid in the capture of nutrients and water in pasture systems by offering complementary rooting architecture to aid in water and nitrogen uptake and decrease nitrogen leaching. Because these species may differ from commonly used grasses and legumes in their seasonal pattern of productivity, they could also extend or enhance growing-season productivity. The goal of this project is to better understand the role of plant diversity in 1) nitrogen use and 2) distribution of rooting dynamics and …


Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham Dec 2010

Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competition between native perennial grasses and Bromus tectorum has been studied for many years. Recently, soil nutrients have been immobilized in an effort to preferentially inhibit growth of B. tectorum relative to native species. Most of this work has focused on soil N, but interactions with soil P are less studied and may be important as well. Additionally, although competitive effects and nutrient responses of several Centaurea spp. are well documented, data are lacking on the competitive effects that Centaurea virgata exerts on the establishment of native and exotic communities. A field experiment and a greenhouse experiment were conducted to …


Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter May 2009

Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent theoretical and technological advances in ecosystem science have dramatically expanded the ways in which scientists can pursue and explore ecological questions. For my thesis research, I integrated the recent theoretical concept of organisms as ecosystem engineers with the relatively recent development of stable isotope tracer tests to ask the question: how does the invasive common carp affect stream ecosystem structure and function? To investigate the structuring role of carp, I measured autotroph seasonal distribution and abundance and macroinvertebrate seasonal abundance and diversity within two stream reaches in Spring Creek, Utah, USA; one with low carp biomass (LCB) and one …


The Role Of Brown Bears (Ursus Arctos) In Nutrient Transport Into Forests Near A Salmon Stream In Coastal British Columbia, Canada, Arthur Morris May 2002

The Role Of Brown Bears (Ursus Arctos) In Nutrient Transport Into Forests Near A Salmon Stream In Coastal British Columbia, Canada, Arthur Morris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients from spawned salmon contribute to the fertility of rivers and riparian areas. Adjacent forests, even far from rivers, could receive substantial amounts of nitrogen and other nutrients from salmon. Since brown bears feed heavily on spawning salmon, bears probably influence the movement of nutrients from salmon into surrounding forests. Because salmon-derived nitrogen is high in 15N, increased isotopic enrichment is expected in forest soils and vegetation if this transport is occurring. Based on relative 15N enrichment of spawning areas, a quantitative estimate of marine-derived nitrogen (MDN) can be obtained using a linear two-source mixing model. To evaluate …


Effects Of Methylene Chloride On Immune Function In Mice And The In Vitro Effect Of Methylene Chloride In Immunologic Assays, Man-Ping Wang May 1989

Effects Of Methylene Chloride On Immune Function In Mice And The In Vitro Effect Of Methylene Chloride In Immunologic Assays, Man-Ping Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of toxicities associated with methylene chloride have been found in both human subjects and mice. However, relatively few studies have probed immunotoxicities of methylene chloride. In order to examine possible immunotoxicities or immunomodulating effects of methylene chloride, several tests of cellular immune function were performed using both human in in vitro studies and a mouse model.

Body weights and specific organ weights of thymus, spleen, liver, and kidney were normal in CD-1 mice given various concentrations of methylenechloride. However, a significantly reduced mitogenic response to phytohemagglutinin (PHA} and reduced interleukin-2 (IL-2} production was found in these methylene-chloride-treated mice. …


Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop May 1988

Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen (N) and energy budgets for free-roaming ewes were quantified on mountain summer range in southwestern Utah in 1986 and 1987. Diet quality (%N), in vitro organic matter digestibility (IVOMD), and energy were estimated with the use of five esophageally fistulated ewes. Excretion rates of N and energy to feces and urine were measured by total collection from five nonfistualted ewes.

Total intake N(gN/(MBW*d-1) tracked intraseasonal changes of dietary N percent but was apparently buffered by fluctuations in dry matter intake. In each year, total urine N was closely related to dietary N concentration, r2=0.97 (1986) …


The Impact Of Surface Soil Removal On Plant Production, Transpiration Ratios, Nitrogen Mineralization Rates, Infiltration Rates, Potential Sediment Losses, And Chemical Water Quality Within The Chained And Reseeded Pinyon-Juniper Types In Utah, Steven M. Lyons May 1978

The Impact Of Surface Soil Removal On Plant Production, Transpiration Ratios, Nitrogen Mineralization Rates, Infiltration Rates, Potential Sediment Losses, And Chemical Water Quality Within The Chained And Reseeded Pinyon-Juniper Types In Utah, Steven M. Lyons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the period of October 1974 to August 1976, a study was conducted to measure the effects of surface soil removal on plant production, plant transpiration rates, nitrate nitrogen mineralization rates, and selected hydrologic parameters (infiltration rates, potential sediment production, and chemical quality of runoff water). The treatments were incremental 7.6 centimeter soil layers to a depth of 30.5 centimeters.

Plant production and transpiration ratios (or water use efficiencies) were measured in greenhouse studies using Agrogyron desertorum grown in the incremental 7.6 centimeter soil layers from five study sites throughout the state of Utah, (Blanding, Brush Creek, Milford, Huntington, and …


Nitrogen Cycling In A Microcosm Simulation Of The Northern Arm Of The Great Salt Lake, John C. Stube May 1976

Nitrogen Cycling In A Microcosm Simulation Of The Northern Arm Of The Great Salt Lake, John C. Stube

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen cycling was studied in the hypersaline northern arm of the Great Salt Lake (332,480 mg/l total dissolved solids) using a sediment-water microcosm simulation of that system. The study demonstrated that nitrate, ammonia, and urea were not stimulating to the halophilic bacteria in the microcosm. The bacteria were simulated only indirectly simulated bacterial growth. In addition, no nitrification could be demonstrated during the study.

Weekly analyses of water samples from the north arm of the lake itself showed that nitrate and nitrite were absent, leaving ammonia as the only significant form of inorganic nitrogen in the northern lake basin. Other …


Forage Yield And Chemical Composition Of An Orchardgrass-Bromegrass Pasture Mixture As Influenced By Clipping Frequency, Nitrogen Fertilization And Irrigation Regime, Vinayak G. Gawai May 1967

Forage Yield And Chemical Composition Of An Orchardgrass-Bromegrass Pasture Mixture As Influenced By Clipping Frequency, Nitrogen Fertilization And Irrigation Regime, Vinayak G. Gawai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of agronomic practices on forage production and chemical composition of an orchardgrass-bromegrass pasture mixture was studied at the Greenville Farm, Logan, Utah, during 1960-1964. The soil is a well drained Millville Silt loam that has about a one percent slope and occurs on an alluvial fan. It is high in potash, phosphorus and calcium and is alkaline having a pH of 7.9 to 8.2.

Analysis of the clipping frequency showed that the yield of forage from four harvests was greater than from five harvests. This difference was greater on plots receiving high rates of nitrogen fertilization, and frequent …


The Effect Of Urea, Ammonium Sulfate, And Organic Materials On Nitrite Accumulation And Gaseous Loss Of Nitrogen In Acid Soil, Siddangouda V. Patil May 1963

The Effect Of Urea, Ammonium Sulfate, And Organic Materials On Nitrite Accumulation And Gaseous Loss Of Nitrogen In Acid Soil, Siddangouda V. Patil

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen is one of the major elements essential for plant growth. It is the element most prone to depletion by cultivation and is usually found deficient in soils. In successful farming the problem of nitrogen supply is of special importance because plants need it in large amounts, it is fairly expensive to supply, and it is easily lost from the soil.


The Influence Of Nitrogen And Phosphorus Supplements On The Composition Of The Ruminal Ingesta Of Sheep Grazing Desert Range Forage, James G. Morris May 1961

The Influence Of Nitrogen And Phosphorus Supplements On The Composition Of The Ruminal Ingesta Of Sheep Grazing Desert Range Forage, James G. Morris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Approximately 46 million acres or 88 per cent of the land area of the state of Utah has been classified by Reuss and Blanch (1951) as "range land open for grazing." Although some of this area cannot be grazed because of inaccessibility, lack of water, poison plants, and similar factors, it is estimated that some 40 million acres or 78 per cent of the total land area is available for grazing. Most of this grazing land is federally owned (73 per cent), while only 22 per cent is privately held, and 5 per cent is state owned.


Root Yields, Sucrose, And Glutamic Acid Content Of Sugar Beets As Influenced By Soil Moisture, Nitrogen Fertilization, Variety, And Harvest Date, Donald G. Woolley May 1956

Root Yields, Sucrose, And Glutamic Acid Content Of Sugar Beets As Influenced By Soil Moisture, Nitrogen Fertilization, Variety, And Harvest Date, Donald G. Woolley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The United States produces about 1.8 million tons of sugar annually. Approximately 75 per cent of this production is derived from sugar beets. The importance of the sugar beet crop in national and world economy is justification for research effort as a means to more economical production.

It is desirable that sugar beet processing be carried out in the most efficient manner. More effective utilization of the sugar beet and its by-products will add stability to the sugar beet industry.

For the past 170 years, since Achard found that sugar could be used for human consumption and that pulp might …


Seasonal Yield And Nitrogen Content Of Three Grasses Grown Alone And In Association With Each Other And With White Dutch Clover, Donald B. Wilson May 1954

Seasonal Yield And Nitrogen Content Of Three Grasses Grown Alone And In Association With Each Other And With White Dutch Clover, Donald B. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The chief aim of pasture research is to discover means of providing the largest possible amount of highly nutritious forage at the time the animal requires it. Throughout the grazing season animal herbage requirements are relatively constant, while herbage production from pastures usually is quite variable.


Nitrogen Content And Protein Yield Of Alfalfa As Influenced By Variety, William H. Bennett May 1948

Nitrogen Content And Protein Yield Of Alfalfa As Influenced By Variety, William H. Bennett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-four alfalfa varieties, representing four varietal groups, were compared for nitrogen content and protein yield. A highly significant difference between varieties was noted for nitrogen content, and a significant difference for protein yield. Saskatchewan 666 had the highest content in the first cutting, but Ledak 22009 had the highest content in the third. Group differences were not significant. Crop differences were highly significant for nitrogen content, yield of forage, and of protein. In the case of every variety, the third cutting was richer in nitrogen than the second and the seemed was richer than the first. Protein yield, however, was …