Soil Science Commons^™

Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt

Dissertations and Theses

Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …

Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse pot …

Incorporating Shear Resistance Into Debris Flow Triggering Model Statistics, Noah J. Lyman

Master's Theses

Several regions of the Western United States utilize statistical binary classification models to predict and manage debris flow initiation probability after wildfires. As the occurrence of wildfires and large intensity rainfall events increase, so has the frequency in which development occurs in the steep and mountainous terrain where these events arise. This resulting intersection brings with it an increasing need to derive improved results from existing models, or develop new models, to reduce the economic and human impacts that debris flows may bring. Any development or change to these models could also theoretically increase the ease of collection, processing, and …

Buried Soil Carbon Vulnerability To Decomposition With Landscape Disturbance, Abby Mcmurtry

Boise State University Theses and Dissertations

Buried layers of ancient soil organic carbon (SOC) can store significant amounts carbon (C). Persistence of this C is favored by burial, which disconnects the soil from atmospheric conditions and limits plant derived C inputs, thus reducing microbial activity. However, erosion exposes buried paleosols to modern surface conditions and results in influx of root-derived C through the processes of root exudation and root turnover. These C inputs stimulate microbial activity and leave paleosol C vulnerable to decomposition. Understanding turnover of ancient soil C is critical for predicting the response of this large C reservoir to environmental change and feedbacks to …

Do Fungal Symbionts Of Salt Marsh Plants Affect Interspecies Competition?, Vanessa Robertson-Rojas

Dissertations and Theses

The effects of arbuscular mycorrhizal fungi (AMF) as salt marsh plant symbionts may have significant effects on landscape scale distribution patterns and plant-related ecosystem functions that are important to estuarine habitats. This work investigates the effects AMF have on Phalaris arundinacea, Deschampsia cespitosa, and Juncus balticus when grown in a common garden experiment. Plants were grown with and without AMF inoculation in both polyculture and monoculture communities and examined for a variety of response variables that represent different competition strategies. Factorial ANOVA analysis revealed a significant three-way interaction among fungal treatment type, community type, and species for …

Snow-Albedo Feedback In Northern Alaska: How Vegetation Influences Snowmelt, Lucas C. Reckhaus

Theses and Dissertations

This paper investigates how the snow-albedo feedback mechanism of the arctic is changing in response to rising climate temperatures. Specifically, the interplay of vegetation and snowmelt, and how these two variables can be correlated. This has the potential to refine climate modelling of the spring transition season. Research was conducted at the ecoregion scale in northern Alaska from 2000 to 2020. Each ecoregion is defined by distinct topographic and ecological conditions, allowing for meaningful contrast between the patterns of spring albedo transition across surface conditions and vegetation types. The five most northerly ecoregions of Alaska are chosen as they encompass …

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 …

The Legacy Of Mining In Southwest Missouri: Past And Present Conditions Of The Tri-State Mining District, Anastasia M C Mcclanahan

MSU Graduate Theses

The historic Tri-State Mining District (TSMD) of southwestern Missouri, southeastern Kansas, and northeastern Oklahoma has a history of lead and zinc mining that extended over a hundred years. During the district’s peak production period, the TSMD was one of the world’s largest producers of lead and zinc. The mining activities in the TSMD produced economic growth that supported the local communities and were essential to the victory of the Allied Forces during World War I and World War II. Beginning in the 1920s, the mining activities in the district slowly began to cease due to depletion of metal ores and …

Influence Of Living Plant Roots And Mycorrhizal Hyphae On Soil Hydraulic Properties, Katelyn M. Marcacci

Masters Theses

The interrelationships between vegetation, soil, and water are fundamental in evaluating the projected impacts of global climate change. Many predictive models require soil hydraulic parameters as inputs. As most hydraulic parameter datasets are for repacked soil, the influence of vegetation on hydraulic parameters is not thoroughly understood. Living roots and mycorrhizal fungi cause physicochemical alterations in soils. Quantifying how vegetation influences soil hydraulic parameters is necessary to more accurately simulate soil water dynamics in climate models.

Laboratory experiments were conducted to test if the presence of roots and roots inoculated with mycorrhizal fungi have a significant effect on the saturated …

Predicting Patterns Of Heavy Metal Contamination In Rio Grande Valley Agricultural Soils, Joy Z. Youwakim

Theses and Dissertations

The Rio Grande Valley of Texas is the statewide leader in the production of produce and grains and is irrigated by the Rio Grande River, in which heavy metal contaminants have been documented by both the International Boundary Water Commission and the United States Geological Survey. This work attempts to observe and document patterns of heavy metal pooling in order to mitigate the increased risk of contamination due to urbanization. We hypothesize that relationships exist between heavy metal content and proximity to roads, land use, and soil type. This research tests these relationships through soil sampling and atomic absorption spectrometry …

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

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) …

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 …

Plant And Soil Responses To Sediment Deposition And Nutrient Enrichment In Healthy, Deteriorating, And Newly Created Coastal Marshes In Barataria Basin, Louisiana: Implications For Mississippi River Sediment Diversions, Gina N. Groseclose

LSU Master's Theses

To offset wetland loss in the Mississippi River Delta, sediment diversions that will re-introduce river water and sediment into wetlands are being planned for the lower Mississippi River. River diversions will also deliver high nutrient loads, which may reduce belowground plant productivity, reducing inputs of organic matter important for marsh accretion to keep pace with sea-level rise. However, belowground productivity responses to the combinatory effects of sediment and nutrients are unknown. To test the hypotheses that nutrient enrichment and sediment deposition interact to influence vegetation structure, belowground plant productivity and decomposition, and surface accretion, a field experiment was implemented in …

Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates

LSU Master's Theses

Man-made levees along the lower Mississippi River prevent delivery of sediment from building and maintaining Louisiana’s coastal wetlands. The Mid-Barataria sediment diversions is designed to reintroduce Mississippi River water, sediment, and nutrients into the sediment-starved Barataria Basin. Phosphorus (P) is an important macronutrient for regulating primary production in coastal marine ecosystems. Wetlands can serve as a sink or source for phosphorus to the overlying water column through various retention and release processes, dependent on concentration. Louisiana coastal systems can be phosphorus limited due to much higher concentrations of bioavailable Nitrogen in river water. The high soluble molar N:P ( >50:1) …

Using Soil Geospatial Properties And Environments To Explore Microbial Diversity, Sharon Faye Smith

Graduate Theses and Dissertations

Soil microorganisms help maintain nutrient cycling, control carbon sequestration, impact plant productivity, and influence several soil chemical and physical properties; yet, the processes that control the microbial composition of soil and how environmental changes may affect the composition and activity of these organisms at different scales remains a difficult and intriguing puzzle for soil scientists, ecologists, and modelers. Wetlands are endangered and important ecosystems that provide several services, which are directly linked to soil function. However, few wetland assessments consider the soil environment and microbial ecology. Linking soil microbial community composition and distribution patterns to soil physio-chemical properties would provide …

Earthworm Dynamics In Tallgrass Prairies In The Ozark Highlands Region Of Northwest Arkansas, Carlee Hensley

Graduate Theses and Dissertations

Tallgrass prairie was a historic and is presently a unique and endangered natural ecosystem throughout the Ozark Highlands region in the mid-southern United States. Tallgrass prairies have been disturbed for agricultural production and/or urban expansion; thus, as a result, efforts have been undertaken to reclaim areas previously used for agricultural production to mitigate the loss of tallgrass prairies. Limited research exists on earthworm dynamics in mounded tallgrass prairies or prairie restorations, particularly in the Ozark Highlands region of northwest Arkansas. The objectives of this study were to i) evaluate the effects of soil moisture regime (SMR; aquic and udic), landscape …

Perceptions Of A Small Midwestern Food Cooperative: A Case Study, Rebecca Forsythe

Theses and Dissertations

The purpose of this research is to illuminate how individuals form perceptions of cooperatives, specifically of Green Top Grocery, a cooperative located in Bloomington Illinois, using the Bourdieu-sian habitus and notions of capital as a frame. Green Top Grocery suffers from fiscal instability since they opened in 2017. They also struggle to gain support of lower income individuals, a key demographic they sought to help since their inception based on their stated values. By conducting qualitative interviews of three sample groups: Green Top Grocery board members and leadership, local food access experts, and West Bloomington residents, and non-participant observations, this …

Determining Geological Controls On Nutrient Availability At Different Depths In The Soils Of The Pelee Island Winery, Lindsay M. Blythe

Electronic Thesis and Dissertation Repository

Terroir describes a sense of place that can give a unique flavour to wines grown in different environments. We explored the role of soil in the terroir at Canada’s most southern vineyard, Pelee Island Winery. This study examined the abundance of major nutrients, trace and rare earth elements of minerals and plant extractable nutrients from 19 soils across the vineyard to a depth of 2 m. We found that bedrock does not influence the element content of Pelee Island soils, the parent materials of the soils are tills and there are geochemical, mineralogical and grain size differences between the two …

Non-Toxic Soil Thickeners For Reducing Mudslide Intensity, Mitchell William Jensen

Materials Engineering

This project was intended to be a continuation of senior project work done last year by a group consisting of two Materials Engineering students and a Soil Science student. Their report was crucial in identifying a range of food thickeners that could be capable of performing in the mud thickening application. All thickeners that were chosen both this year and last year are biocompatible, to alleviate some toxicity concerns. The food thickeners all belong to a class of compounds known as colloids. Since water is the fluid being thickened, these compounds are more accurately referred to as hydrocolloids. Hydrocolloids are …

The Strawberry Rhizosphere Microbiome: Role On Plant Health And Nutrition, Eric Michael Boyd

Master's Theses

Microbial-root associations are important to help plants cope with abiotic and biotic stressors. Managing these interactions offers an opportunity for improving the efficiency and sustainability of agricultural production. By characterizing the bacterial and archaeal community (via 16S rRNA sequencing) associated with the bulk and rhizosphere soil of sixteen strawberry cultivars in two controlled field studies, we explored the relationships between the soil microbiome and plant resistance to two soilborne fungal pathogens of strawberry (Verticillium dahliae and Macrophomina phaseolina). Overall, the plants had a distinctive rhizosphere microbiome relative to the bulk soil, with higher abundances of known beneficial bacteria …

Host Plant Resistance In Strawberries To Anthracnose And Colonization Of Crown And Root Tissue By Verticillium Dahliae And Macrophomina Phaseolina, Omar A. Gonzalez-Benitez

Master's Theses

Strawberries are considered an important crop in California where in 2018 it was in the top 5 valued fruit and vegetable commodities valued at $2.84 billion accounting for 88% of the total U.S. production. Strawberry production can be severely impacted by soilborne pathogens that can affect strawberry roots, crowns and leaves which can result in plant mortality. As much as 50 to 60% mortality can occur in one field. Pathogens responsible for such losses include Colletotrichum acutatum (syn.C. nymphaeae), Macrophomina phaseolina and Verticillium dahliae. With the phaseout of methyl bromide, host resistance and an understanding of host-pathogen interactions …

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle

Master's Projects and Capstones

Wildfires in the mixed conifer forests of California’s Sierra Nevada have been a common and natural disturbance for thousands of years, historically occurring every 3 to 30 years. The flora and fauna of the mixed conifer forest have evolved to depend on low to moderate severity wildfires for reproduction, foraging, and habitat. However, the Sierra Nevada has experienced dramatic environmental changes over the past ~150 years as a result of three main factors: wildfire suppression, climate change, and habitat loss. Because of the threat wildfires pose to human lives, property and timber harvest, they have been suppressed to an extent …

Soil Quality Tests For Classroom Use, Kathleen Thompson

Theses/Capstones/Creative Projects

Soil analysis can traditionally be carried out by professional labs for a certain price, but this price adds up quickly when running many samples—as is often the case when pursuing a research question. Price is of particular concern in the classroom setting, where funding for student research can be limited.

This project examines several commercially produced soil test kits that are capable of testing a soil’s pH, nitrogen, phosphorus, and potassium; parameters which are of primary importance for plant growth. The project provides an overview of each kit’s contents and properties, a scientific assessment of their precision and accuracy, and …

Infiltration Into Water-Repellent Sand: The Role Of Sorptivity, Rose Marie Shillito

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soil water repellency (SWR) is believed to contribute to the increased potential for post-fire runoff and erosion. Currently, no quantitative method exists to account for SWR in physically-based runoff models. A physically-based model incorporating SWR (through the contact angle) in the infiltration parameter, sorptivity, was developed. The model was tested and verified with controlled laboratory tests on a fully characterized sand treated to create various degrees of SWR. The ability to create the wetting water characteristic curve for untreated and treated sand, appropriate for the infiltration process, was presented. Additionally, the ability to measure sorptivity with widely used infiltration tests …

Quantifying Greenhouse Gas Emissions And Ammonia Volatilization From Soil Amended With Excreta From Ruminants Fed Alternative Forage-Based Diets, Samuel Park

Graduate Theses and Dissertations

Forage-based ruminant diets supplemented with condensed tannins or polyphenolic-containing legumes may alter nitrogen (N) metabolism in the animal and reduce gas emissions from soil receiving excreta. The objective of the study was to determine if soil receiving urine or manure from sheep fed forage diets supplemented with condensed tannin or polyphenolic-containing legumes would decrease N gas emissions. Two field trials were conducted: in the first trial, sheep were fed alfalfa (Medicago sativa L.) silage diets supplemented with 0, 9, 18, or 27% sericea lespedeza (Lespedeza cuneate [Dumont de Courset] G. Don) (n = 4). In the second trial sheep were …

Soil Microbial Diversity And Litter Decomposition Increase With Time Since Land Use Disturbance In Tropical Montane Forests Of Malaysian Borneo, Renee Sniegocki

Graduate Theses and Dissertations

Logging and forest conversion are occurring at alarming rates in the tropical forests of Southeast Asia. These disturbances alter soil chemistry, microbial diversity, and disrupt carbon cycling through shifts in litter decomposition. Direct links between microbial diversity and soil properties such as pH are well established; however, the indirect impacts of logging and forest conversion on microbial diversity and litter decomposition are poorly understood. We used surface (5 cm) soil to assess soil physicochemical properties, next-generation DNA sequencing to assess soil microbial diversity, and standardized litterbags to assess litter decomposition stabilization at five sites along a land use disturbance gradient …

Analyzing The Effects Of Of Seasonal Land Cover And Precipitation On The Sediment Delivery Ratio Of An Agriculture Dominated Watershed., Jonah Liebman

Electronic Theses and Dissertations

Soil erosion is of escalating importance as increasing population and climate change have put increasing pressures on agricultural food production. Vegetation and precipitation are two factors that control the amount of soil erosion extant within a region. Sediment delivery ratios (SDRs) assess the ratio of soil eroded from a watershed system that is permanently removed from the system through stream sediment discharge. Using 1) river discharge and sediment concentration data and 2) the Revised Universal Soil Loss Equation (RUSLE), this thesis analyzes fluctuations in monthly SDRs for an average hydroclimatological crop-harvest season for the Senachwine Creek watershed, IL. Through calculating …

Mechanisms Of Carbon Movement And Stabilization In Mangrove Wetlands, Carey Schafer

USF Tampa Graduate Theses and Dissertations

Mangrove forests have higher rates of carbon storage per unit area than any other coastal or terrestrial habitat, largely due to their significant soil stocks. More effort has been placed on quantifying mangrove soil carbon stock, the amount of carbon stored in the upper meter of mangrove soils, than identifying the processes governing in situ soil organic carbon (SOC) cycling and stabilization. An understanding of the mechanisms related to carbon transport and stability is necessary to constrain current wetland carbon stocks and to determine how sea level rise will impact future carbon stores. This study uses a variety of radiometric …

Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan

LSU Doctoral Dissertations

The impacts of sea-level rise and hydrologic manipulation are threatening the stability of coastal marshes throughout the world, thereby increasing the potential for re-mineralization of soil organic matter (SOM) in these systems. Such threats have prompted marsh restoration efforts, particularly in coastal Louisiana, yet it is unclear how the slowly decomposing (refractory) and quickly decomposing (labile) fractions of SOM may be differentially affected by different approaches to marsh restoration. Additionally, otherwise labile compounds may accumulate in the soil via a range of protective mechanisms, including rapid burial and association with organic compounds that are thought to enhance soil aggregation, such …