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Full-Text Articles in Soil Science

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling May 2024

Soil Reclamation Strategies In Construction Disturbed Soil, Alexis Koelling

All Graduate Reports and Creative Projects, Fall 2023 to Present

The rapid urbanization occurring in arid environments like the Intermountain West region of the U.S. significantly alters soil conditions. Construction of roads, buildings, and other infrastructure leads to the disturbance of soil structure, nutrient depletion, and reduced fertility. This research addresses the need for sustainable soil management practices that may restore soil health post-construction. In this study, the effectiveness of various soil amendments and application methods on specific soil parameters and turfgrass establishment in construction-disturbed soils was evaluated. The study highlights the critical role of soil amendments, particularly municipal solid waste (MSW) compost, in improving soil quality and plant growth. …


Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti May 2024

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …


Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner Dec 2023

Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner

All Graduate Reports and Creative Projects, Fall 2023 to Present

Phosphorus (P) is considered immobile in calcareous soils. Organic matter is known to enhance P mobility in these soils. Few studies have considered what role iron oxides might play in P sorption in calcareous soils, especially in the presence of soluble organic matter. This study investigated P sorption dynamics in sand-based, simulated soil systems in the absence or presence of 5 mM carbon (C) as humic acid (HA). Treatments included combinations of dicalcium phosphate dihydrate (DCPD), calcite, and ferrihydrite. Solutions containing 10 mg P L-1 in a background of 0.01 M CaCl2were equilibrated with each solid treatment …


Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle Dec 2023

Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle

All Graduate Theses and Dissertations, Fall 2023 to Present

Recently, the US has seen an expansion in the amount of turfgrass land cover (lawns, parks, roadsides, sports fields, and golf courses), as well as an interest in reducing fertilizer, water, and pesticide use in these grass systems. To help maintain quality and function while reducing resource inputs, two promising approaches have emerged: planting clover into lawns and applying plant growth-promoting rhizobacteria.

White clover and grass mixtures have been studied for their ability to cut down on fertilizer usage and provide a uniform, dark green lawn, but other clover types have not been as widely studied and may provide similar …


Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger Dec 2023

Ecology And Management Of Dyer's Woad (Isatis Tinctoria) In Northern Utah, Erin Marie Hettinger

All Graduate Theses and Dissertations, Fall 2023 to Present

Dyer’s woad (Isatis tinctoria L.) is a non-native forb that continues to threaten natural areas throughout Northern Utah and much of the Intermountain West. Once introduced, dyer’s woad can become extremely invasive, decreasing forage quality, and displacing native species. While dyer’s woad is found throughout much of Northern Utah, its range in other states remains limited. If promptly managed, control success in these areas will be much higher and populations may be kept at bay before ecological damage becomes severe.

This project tested the ability of dyer’s woad seedlings to compete with common rangeland grasslands at varied densities as …


Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel May 2023

Daytime Versus Nighttime Sprinkler Irrigation Of Two Urban Crops In A Semi-Arid Climate At High-Elevation, Samikshya Pyakurel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nighttime irrigation scheduling is a longstanding water conservation approach to reduce evaporative losses in Utah's semi-arid, urban landscapes. However, residential demand now exceeds system capacity, and the efficiency of the practice has come under question. Therefore, the objectives of this study include: 1) quantify whether a water savings exists between day and night irrigation with a water balance and energy balance approach, and 2) analyze microclimate and crop quality effects to determine any changes to evaporative demand or plant stress by irrigation timing. In 2019, we established 12 field plots in North Logan, UT (41.77° N, -111.81° W, 1380 m …


Urban Soil Chemical And Nutrient Management Issues Facing Emerging Small Grower Enterprises In Utah, Frank E. Oliver Aug 2022

Urban Soil Chemical And Nutrient Management Issues Facing Emerging Small Grower Enterprises In Utah, Frank E. Oliver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of both soil quality and contamination has become increasingly important with the growth of urban agriculture in Utah and the United States as whole. Land is also a common limiting factor in urban agriculture, so it is important to maximize yield and net returns. In order to meet these demands, three studies were conducted across key urban agriculture sites along the Wasatch Front: 1) an urban soil survey to assess soil contamination, 2) an urban soil survey to evaluate macronutrient and salinity levels, and 3) a nitrogen fertilizer management trial for dahlia (Dahlia pinnata), a cut flower …


Nitrogen Fertilizer Showed Little Effect On First- And Second-Year Corn Yield And Quality Following Alfalfa, Bailey Brent Shaffer Aug 2021

Nitrogen Fertilizer Showed Little Effect On First- And Second-Year Corn Yield And Quality Following Alfalfa, Bailey Brent Shaffer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silage corn (Zea mays L.) following alfalfa (Medicago sativa L.) is a common crop rotation in Utah and southern Idaho. This is done, in part, to take advantage of residual nitrogen (N) fixed by bacteria that work in symbiosis with the roots of alfalfa. After alfalfa is terminated, much of the N that was fixed by the plant is released into the soil and becomes available for use by the rotational crop. This reduces the amount of N fertilizer that growers need to apply. The Utah Fertilizer Guide currently recommends an N credit to a rotational crop following …


Boron In The Pariette Wetlands, Uinta Basin, Ut, Palak Vasudeva Aug 2020

Boron In The Pariette Wetlands, Uinta Basin, Ut, Palak Vasudeva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Boron is a naturally occurring mineral in shale and coal beds formed in marine environments, as found in the Uinta Basin. Mining activity and the application of excess irrigation water on agricultural lands in the Pariette watershed lead to mobilization of B via surface run off. Water quality monitoring records from 2006- 2009 reported violations of Utah B standard for irrigation water 43-100% of the time, for water flowing through the Pariette Wetlands. This study aims to determine B distribution in abiotic (water, sediments) and biotic samples (macroinvertebrates, aquatic vegetation, fish, bird eggs), and to establish correlations between B concentrations …


Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik Aug 2020

Effect Of Plant Derived Tannins On Nitrogen And Carbon Cycling In Pasture Soils, Kathryn A. Slebodnik

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pasture-finished beef has become increasingly popular, but nitrogen losses from these pastures are of concern. Legumes containing condensed tannins such as birdsfoot trefoil (Lotus corniculatus) and sainfoin (Onobrychis viciifolia) may serve as environmentally and economically viable alternative forages in pasture finishing systems while reducing soil nitrogen loss. The goal of this project was to understand how tannin type and concentration affects soil nitrogen cycling both in the lab and the field. This thesis: 1) compared the physical, chemical, and biological characteristics of soil samples obtained from grazed grass and tannin and non-tannin containing legume pastures, 2) …


Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound Aug 2020

Nitrogen Fertilizer Needs Of First-Year Small Grains Following Alfalfa, Collin Pound

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wheat, barley, triticale, and oats, are small grains commonly grown as hay and grain following alfalfa in Utah and the Intermountain West, especially during drought years as they require less irrigation than corn. Several studies in many parts of the world have shown that first-year corn following alfalfa rarely needs nitrogen (N) fertilizer, yet relatively few have evaluated the N needs of small grains, especially small grains grown for hay. Objectives of this research were to determine whether N fertilizer is needed to economically optimize the yield and quality of first-year small grains following alfalfa, develop N guidelines, and whether …


Soil Health Assessment On Arid Rangeland Soils Impacted By Oil And Gas Exploration, Development, And Extraction, Justin Allred Aug 2020

Soil Health Assessment On Arid Rangeland Soils Impacted By Oil And Gas Exploration, Development, And Extraction, Justin Allred

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oil and gas well pad reclamation in arid environments such as in the Uinta Basin of Utah, presents unique challenges, including remote locations, limited water, and elevated soil salinity and sodicity. Successfully reclaimed Plugged and Abandoned (P&A) well pads should resemble the surrounding rangeland once fully reclaimed. Revegetation of native species is the primary indicator of successful reclamation, but the lack of water makes it challenging to re-seed native plants, while trying to prevent the encroachment of invasive plant species such as Bromus tectorum (cheatgrass), Salsola tragus (Russian thistle), and Halogeton glomeratus (halogeton). Could successful reclamation be reflective of good …


Assessing Amendment Treatments For Sodic Soil Reclamation In Arid Land Environments, Sandra Udy Dec 2019

Assessing Amendment Treatments For Sodic Soil Reclamation In Arid Land Environments, Sandra Udy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plugged and abandoned well pads throughout the Uintah Basin face reclamation challenges due to factors including a harsh climate, invasive species, and high salt loads. Finding ways to alleviate soil sodicity could improve soil reclamation success. Gypsum, sulfur, activated carbon, and Biochar are being applied to improve soil parameters negatively impacted by sodicity, but the direct impact of these amendments on Uintah Basin soils is still largely unknown. The aim of this study was two-fold. (1) Evaluate the effectiveness of gypsum, sulfuric acid, Biochar, activated carbon, and combinations of these amendments in reducing the impact of soil sodicity of the …


Phosphorus Rate Effects With And Without Avail® On Dryland Winter Wheat In An Eroded Calcareous Soil, Ryan C. Hodges May 2019

Phosphorus Rate Effects With And Without Avail® On Dryland Winter Wheat In An Eroded Calcareous Soil, Ryan C. Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soluble phosphorus fertilizer is bound in the soil rapidly after application in soils high in calcium. A fertilizer additive known as AVAIL® (J.R. Simplot Company) is purported to keep applied phosphorus fertilizer more available to plants by binding to soil minerals such as calcium, magnesium, and iron, thereby reducing phosphorus binding. This could prove useful due to the attraction of AVAIL® with cations such as Ca2+, but is fairly unstudied for dryland wheat production on alkaline, calcium-rich soils. The objective of this study is to evaluate the effect of low-rate fertilizer treatments with AVAIL® on dryland small grain …


Non-Methane Hydrocarbon Source Apportionment And Btex Risk Assessment Of Winter 2015 In Roosevelt, Utah, Jerimiah Lamb Dec 2017

Non-Methane Hydrocarbon Source Apportionment And Btex Risk Assessment Of Winter 2015 In Roosevelt, Utah, Jerimiah Lamb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-Methane Hydrocarbons (NMHC) monitored in Roosevelt Utah including Benzene, Toluene, Ethylbenzene and Xylene (collectively known as BTEX) are associated with deleterious effects including cancer. This study was designed to assess the origin and effect of the toxicants and addressed two points: 1) Source identification using the USEPA’s Positive Matrix Factorization (PMF) and NOAA’s Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model and 2) A human health risk assessment based on ambient concentrations of BTEX collected at the Roosevelt site. Model fit indicated that the primary contributor to total NMHCs was local oil and gas operations and was supported by previous …


Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča May 2017

Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil organic carbon (SOC) positively affects many soil properties (e.g., fertility and water holding capacity), and the amount of carbon (C) in soil exceeds the amount in the atmosphere by about three times. Forest soils store as much C as is found in trees. Tree species differ in their effect on SOC pools. Quaking aspen forests in the Western US often store more stable SOC in the mineral soil than nearby conifers. During the last decades a decline in aspen cover, often followed by conifer encroachment, has been documented. A shift from aspen to conifer overstories may negatively affect the …


Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding May 2017

Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Uinta Basin hookless cactus (Sclerocactus wetlandicus) is a threatened species native to Eastern Utah. The cactus is found in a landscape highly disturbed by non-renewable energy production. To understand the environmental conditions that support natural growth of this cactus, we asked what types of plants were present in the same areas as the cactus, and if the types of plants were different in environments that were disturbed. From our assessment, we determined that the types of plants present in disturbed areas were drastically different from those present in undisturbed locations. Areas previously used for energy production are …


Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen Dec 2016

Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil health is often overlooked as a long-term management strategy as growers face an increasing number of short-term management challenges in the Intermountain West. The costs of inputs are rising and water resources are becoming more limited. Soil with poor health typically requires more amendments and fertlizers to meet crop needs. Soil health tests can help reveal management practices that reduce soil health, as well as those that improve soil health. Practices known to improve soil health are reduced to no tillage, cover crop use- especially legumes, and addition of mulch and other organic materials. Soil health testing is not …


Digital Soil Mapping Using Landscape Stratification For Arid Rangelands In The Eastern Great Basin, Central Utah, Brook B. Fonnesbeck May 2015

Digital Soil Mapping Using Landscape Stratification For Arid Rangelands In The Eastern Great Basin, Central Utah, Brook B. Fonnesbeck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In some parts of the western US there is limited publicly available soil information that can be used to make land management decisions on both public and private land. A goal of the USDI Bureau of Land Management (BLM) in Utah was to map an area in central Utah where such soil maps and value-added information was not available for management and restoration decisions following a wildfire. In 2007, the Milford Flat Fire had burned more than 363,000 acres, removing vegetation that was holding erosion-sensitive soils in place. Following inconsistent results from stabilization and restoration efforts, this study was funded …


Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga May 2014

Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Growing populations, coupled with climate change and resource depletion, have heightened concern about water management. The growing need to better manage agricultural systems, including irrigation and fertilizer application, as well the lasting consequences of excess application of nitrogen and other nutrients, could be remedied with an improved method to monitor soil water movement. Despite huge technological advances, a tool to measure soil water flow at the low rates found in the field has not been developed. Current methods lack the precision to provide the needed accuracy to fully understand soil-water dynamics, as well as the ability to provide instantaneous information. …


Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv May 2014

Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration (ET) and soil moisture play important roles in annual water delivered from snowpack to reservoirs, lakes and streams. Indeed, ET and soil moisture are key factors dictating the performance of the regional climate models in the intermountain west (IMW) of the USA. Water resources management and climate modeling require accurate prediction of ET and areal soil moisture for reliable estimates of ongoing and future water needs. This research has examined ways to estimate ET from four common vegetation types in the IMW (aspen, conifer, grass and sage) using local soil moisture measurements from an advanced instrumentation network located in …


Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran Dec 2013

Methylmercury Fate In The Hypersaline Environment Of The Great Salt Lake: A Critical Review Of Current Knowledge, Danielle Barandiaran

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Methylmercury (MeHg) is a highly potent neurotoxic form of the environmental pollutant Mercury (Hg). The processes that are responsible for the conversion of Hg to MeHg are known to be both biotic and abiotic in freshwater systems. Although MeHg contamination is well documented in Great Salt Lake (GSL), the conversion of Hg into MeHg is not well-understood in saline environments much less in hypersaline waters such as GSL. The GSL is a broad, shallow high altitude (1280 m above sea level) lake that is exposed to large amounts of ultraviolet radiation and evaporation, which lead to great volatilization losses of …


Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch May 2011

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …


Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland Dec 2010

Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A soils infiltration rate (IR) is the measured rate that soil is able to absorb water, either from precipitation or irrigation. A low IR can cause damage to crops if the necessary amount of water cannot penetrate to the plant roots in the time needed. The damage can be common in permanent plantings such as almond and pistachio orchards where regular tillage is avoided. This indicates a physical aspect to the problem because tillage increases IR. However, there is also an electrochemical side to infiltration problems because certain calcium surfactant treatments can increase IR. Various other methods have been used …


Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum May 2010

Random Forests Applied As A Soil Spatial Predictive Model In Arid Utah, Alexander Knell Stum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Initial soil surveys are incomplete for large tracts of public land in the western USA. Digital soil mapping offers a quantitative approach as an alternative to traditional soil mapping. I sought to predict soil classes across an arid to semiarid watershed of western Utah by applying random forests (RF) and using environmental covariates derived from Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and digital elevation models (DEM). Random forests are similar to classification and regression trees (CART). However, RF is doubly random. Many (e.g., 500) weak trees are grown (trained) independently because each tree is trained with a new randomly …


Salinity Inventory And Tolerance Screening In Utah Agriculture, Austin Mccoy Hawks Dec 2009

Salinity Inventory And Tolerance Screening In Utah Agriculture, Austin Mccoy Hawks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil salinity, a yield-limiting condition, has plagued crop production for centuries by reducing crop productivity. Research has introduced methods for successfully managing soil salinity. This research discusses the adaptation of established management methods to create new soil salinity management techniques.

One adapted technique is an automated crop screening apparatus. A new design was created and successfully used in rapidly screening two strawberry cultivars to determine their tolerance to salinity. Screening crops and determining their tolerance to yield-limiting conditions are essential in managing soil salinity.

Another salinity management tool used in this research was electromagnetic induction (EMI). EMI was used to …


Soil Organic Carbon And Site Characteristics In Aspen And Evaluation Of The Potential Effects Of Conifer Encroachment On Soil Properties In Northern Utah, Mical K. Woldeselassie May 2009

Soil Organic Carbon And Site Characteristics In Aspen And Evaluation Of The Potential Effects Of Conifer Encroachment On Soil Properties In Northern Utah, Mical K. Woldeselassie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the Intermountain West, aspen (Populus tremuloides) has declined mainly due to a combination of successional processes, fire suppression and long-term use of ungulates which has led to replacement by conifers, sagebrush or other shrub communities. Conifer encroachment is believed to cause critical changes in the ecosystem properties. In order to understand the impacts of conifer encroachment on soil properties such as soil organic carbon (SOC) storage, soil morphology, and soil chemical properties, and the implications of such changes, it is very important to assess the soil properties under the two vegetation types. The objectives of this study …


Identification Of Subsoil Compaction Using Electrical Conductivity And Spectral Data Across Varying Soil Moisture Regimes In Utah, Jay Murray Payne Dec 2008

Identification Of Subsoil Compaction Using Electrical Conductivity And Spectral Data Across Varying Soil Moisture Regimes In Utah, Jay Murray Payne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Subsoil compaction is a major yield limiting factor for most agricultural crops. Tillage is the most efficient method to quickly treat compacted subsoil, but it is also expensive, increases erosion, and accelerates nutrient cycling.

The use of real-time electrical conductivity (EC) and near-infrared (NIR) reflectance values to differentiate compacted areas from uncompacted areas was studied. This method has potential to reduce monetary and time investments inherent in traditional grid sampling and the resultant deep tillage of an entire field. EC and NIR reflectance are both very sensitive to spatial variability of soil attributes.

The objective of this research was to …


Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen Dec 2008

Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the dramatic expansion of pinyon-juniper woodlands over the last century, improved understanding of how these woodlands modify infiltration properties is needed, in order for land managers to make informed decisions on how to best manage their specific resources. However, current methods for measuring soil infiltration are often limited by low sample sizes and high experimental error, due to constraints associated with remote, non agricultural settings. This thesis first presents a scheme for automating and calibrating two commercially available infiltrometers, which allows collection of a large number of precise unsaturated infiltration measurements in a relatively short period of time. Secondly, …


Optimal Irrigation Management For Sloping, Blocked-End Borders, Jorge Jose Escurra Dec 2008

Optimal Irrigation Management For Sloping, Blocked-End Borders, Jorge Jose Escurra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A robust mathematical model of one-dimensional flow for sloping, blocked-end border irrigation was developed using the four-point implicit method to solve the Saint-Venant equations, the volume-balance solution method, and the implementation of new algorithms to avoid numerical instability and solution divergence. The model has the capability of successfully simulating all surface irrigation phases in blocked-end borders for a range of inflow rates (0.01 - 0.05 m3/s per m), longitudinal slopes (up to 1.00%), and border lengths (100 - 500 m).

To achieve numerical stability over the specified parameter ranges, the model was divided into three parts: (1) advance-phase …