Life Sciences Commons^™

Near-Surface Soil Property Change Over Time In Two Native Tallgrass Prairies In The Arkansas River Valley, Katie Jansson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

One climate-change mitigation pathway is soil carbon (C) sequestration, which removes carbon dioxide from the atmosphere and stores C in various forms in the soil. Native prairie soils have long been known for their soil C sequestration abilities, but the full extent of their sequestration capacity is not completely understood. This study evaluated the effect of soil depth and soil map unit/prairie combination on changes in various soil properties over time from 2018 to 2022 in the top 20 cm of two native tallgrass prairie soils in the Arkansas River Valley in west-central Arkansas. Soil samples were collected from the …

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 …

Impact Of Cover Crop Species Diversity On Soil Nutrient Availability And Crop Productivity, Amanda Kramer

Masters Theses

Cover crops provide multiple environmental benefits that improve both soil and water quality; however, farmers only utilize them on approximately 5% of harvested U.S. cropland. Low adoption rates are attributed to yield impact concerns, seed and planting costs, and lack of advocacy. This study, which began in October 2019, assessed the effects of nitrogen rate and cover crop diversity on weed biomass, soil coverage, in-situ residue decomposition, soil nitrogen and phosphorus availability, and cash crop yield to better understand the costs and benefits of cover crop adoption at two locations in Tennessee (Milan and Spring Hill). Treatments were replicated 4 …

Distribution Patterns Of Allorhizobium Vitis In Missouri Vineyards And Non-Vineyard Soils, Jacquelyn M. Wray

MSU Graduate Theses

Crown gall disease causes significant economic loss to the grape and wine industry. Preventive strategies are most effective for mitigating the loss of grapevines in vineyards, as there is no known cure for this disease. The bacterium Allorhizobium vitis carrying a tumor-inducing (Ti) plasmid is the causative agent. A. vitis bacteria live systemically in the grapevine before causing visible symptoms and can survive in residual plant tissues and soil for more than two years. Diagnostic methods have been developed to detect A. vitis bacteria in grapevines and soil. However, more reliable, specific, and high-throughput diagnostics are still needed for screening …

Nitrogen Transfer From Cover Crops To The Subsequent Grain Crop And The Influence Of Variability In Winter Conditions, Spencer Heuchan

Electronic Thesis and Dissertation Repository

Cover crops, which are used to provide ground cover after the harvest of the grain crop, can potentially improve the sustainability of agroecosystems by reducing nutrient losses. However, few data are available to document the extent to which cover crops improve both the retention of soil nitrogen (N) and the transfer of this N to the grain crop. The efficiency of this N transfer may be further influenced by variation in winter soil temperature; for example, reduced snow cover can increase the frequency and intensity of soil freezing, which can affect the survival of cover crops and the timing of …

Diagnosing Excess Nitrogen In Rice Using Post-Season Tissue Samples, Kyle Hoegenauer

Graduate Theses and Dissertations

Proper nitrogen (N) management in rice production can be difficult to achieve without the aid of tools such as soil and tissue tests. There are no tests currently available to rice producers that determine whether N has been managed properly throughout the season or that detect instances of over fertilization. Rice stalk samples were collected from N response trials within 3 days of harvest from the primary Arkansas rice growing region in 2016-2018. Stalk samples were analyzed for N concentration through a KCl extraction and spectrofluorometric quantification. Samples analyzed with leaf material intact contained statistically different N concentrations than samples …

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …

The Analysis Of Ginsenosides In Ginseng Garden Soil, Karina Marie Kaberi

Electronic Thesis and Dissertation Repository

American ginseng (Panax quinquefolius L.) produces natural products called ginsenosides. The biggest challenge Ontario commercial ginseng farmers face is ginseng replant disease. To understand the function of ginseng root exudates, ginsenoside accumulation and persistence over time were investigated. Currently, no reliable ginsenoside specific extraction method, characterizing the changes in soil chemistry exists. Ginsenoside extraction protocol optimization was required to determine how ginsenoside composition changed over time. Overall, protocol optimization resulted in a 30% increase in yield of ginsenosides compared to previous extraction protocols. In the ginseng gardens, ginsenoside accumulation occurs slowly and did not reach significantly measurable amounts until the …

Effects Of Traditional And Microbially-Focused Restoration Techniques On Soil Communities In Tallgrass Prairies, Zachary J. Whitacre

Masters Theses

Tallgrass prairies have virtually disappeared in many parts of their former range due to the conversion of this ecosystem to farmland. In more recent years there have been efforts to restore these prairies on reclaimed agricultural land. However, these restored prairies do not resemble their remnant counterparts in many ways, such as in soil microbial community composition and metrics related to carbon storage. In Chapter 1, I show that bacterial communities in a restored prairie and an adjacent remnant prairie in southwest Michigan differ in their immediate and longer-term responses to prescribed fire, a commonly used prairie restoration and maintenance …

Effects Of Am Fungi From Conventional And No-Till Michigan Crop Fields On Plant And Soil Health, Derek Bennett

Masters Theses

Centuries of conventional till (CT) management in agriculture has depleted soil organic matter (SOM) by over 50%. While only comprising 5% in most soils, SOM provides soil with fertility and productivity. To compensate for SOM depletion, producers have been forced to increase their reliance on fertilizer and irrigation to maintain yields. In the coming decades, climate change is expected to challenge food production and threaten an already fragile system. With no remaining land left to cultivate, conservation management strategies such as no-till (NT) look to restore SOM and increase the resilience of food production for an ever growing, increasingly food …

Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden

Graduate Theses and Dissertations

As the number one rice (Oryza sativa)-producing state in the United States, Arkansas also ranks fourth as the largest user of groundwater. Recently, due to the development of drought- resistant hybrid cultivars, the furrow-irrigated rice production system has become an increasingly popular alternative to traditional flood-irrigated production with respect to conserving groundwater and maintaining yield. However, other environmental parameters, like greenhouse gas emissions, specifically nitrous oxide (N2O), have yet to be evaluated under furrow-irrigated rice. The objectives of this study were to i) evaluate the effects of site position (i.e., up-, mid-, and down-slope) and tillage treatment [i.e., conventional tillage …

Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz

Graduate Theses and Dissertations

Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …

Evaluation Of Soil Type And Seeding Rate On Winter Cover Crop Species In A Soybean Production System, Donna S. Morgan

LSU Doctoral Dissertations

The integration of winter annual cover crops into a cropping system can potentially improve soil health and crop production, however, the impact of variables such as seeding rates, across two very different soil types, has not been well documented. A two-year study was conducted at the Dean Lee Research Station and Extension Center in Alexandria, Louisiana to evaluate the effects of cover crop seeding rate and soil type on cover crop biomass, weed suppression, soil fertility, and soybean (Glycine max L) growth and yield. Analysis of potential economic impacts was also performed to estimate financial net returns for three …

Ecosystem Function Along An Elevational Gradient In Vermont, Emily Page Piche

Graduate College Dissertations and Theses

Living (biotic) and non-living (abiotic) factors drive the function of ecosystems across a variety of scales from the root-soil interface to the watershed. Biotic and abiotic global change pressures such as increasing temperature and invasive species are shifting how ecosystems function. Thus, exploring and understanding how these factors shape function across the landscape is an important research area. For example, climate change both directly and indirectly affects soil microbial functions – such as carbon mineralization and nitrogen transformations – through increasing activity under warming and altering inputs to the soil through species composition changes. Mountains provide a useful tool for …

Biological Soil Crusts In A Northeastern Pine Barren: Composition And Ecological Effects, Jessica Gilbert

Honors Theses

Biological soil crusts (BSCs), otherwise known as cryptogamic soil crusts, biocrusts, or cyanobacterial crusts, are soil aggregations hosting diverse biotic communities. They are composed of cyanobacteria and algae, and generally have a covering of moss and/or lichen. BSCs are typically found in arid to semi-arid regions throughout the world, and are integral soil stabilizers, moisture retainers, and nitrogen fixers in these communities. Along with these factors, BSCs are able to impact germination and establishment of plants, either as an accompanying influence, or direct result of those listed above. BSCs have yet to be formally described in the inland northeastern United …

Soil Properties That Influence The Occurrence Of Hydrogen Sulfide Toxicity In Rice Fields, Julia Marie Fryer

Graduate Theses and Dissertations

Rice (Oryza sativa L.) producers face many challenges throughout each growing season. Hydrogen sulfide (H2S) toxicity is a physiological disorder where sulfate (SO42-) is excessively reduced to the toxic gas, H2S. This can reduce yield and, in severe cases, result in crop death. The main research objectives were to: i) understand chemical and physical characteristics in soils prone to H2S toxicity, ii) determine influential soil characteristics on the incidence of H2S toxicity, iii) determine ammonium sulfate ((NH4)2SO4) fertilizer additions influence on H2S toxicity, and iv) predict when and where H2S will occur. Three greenhouse experiments were conducted using Arkansas field …

Landscape Foundations: A Practical & Technical Guide To Landscape Maintenance, Marco Crosland

Undergraduate Honors Theses

Many homeowners struggle to maintain healthy landscapes. Often, they simply don’t understand basic principles that, if followed, would make a significant difference in the health and appearance of their landscape. The hope of Landscape Foundations is to help homeowners maintain healthy and excellent landscapes by teaching these “correct principles”.

What makes Landscape Foundations different than other landscape guides is that it brings in current research and explains it in a simple way. This guidebook provides pictures and additional resources to explain landscape maintenance principles. It teaches both the practical and technical sides.

Landscape Foundations is written for both beginners and …

Soil-Grapevine Interactions: Insight From Verdicchio In The Marche Wine Region, Italy, Megan Luna Barlow

Theses and Dissertations

Verdicchio is a white grape varietal notably grown in the Marche wine region of east-central Italy within two Denominazione Origine Controllata (DOCs); Castelli di Jesi and Matelica, located less than 50 km apart. Jesi lies in the Apennine foothills near the coast of the Adriatic Sea and produces a smooth wine noted with apple-pear undertones and crisp, clean acidity. Conversely, Matelica is located in a synclinal valley of a fold-and-thrust belt and produces stronger wine with penetrating floral aromas and bold acidity. While macro-climatic variations do exist between DOCs, this research focuses on geological variations, specifically variations in soil composition, …

Evaluating Mine Soil Prepared By Scraper Pans For Herbaceous Plants And Pine Seedlings At An East Texas Lignite Surface Mine, Hannah Z. Angel

Electronic Theses and Dissertations

Since 1974, Luminant Mining Company, LLC (Luminant) has planted over 38.7 million trees on its reclaimed lignite surface mine operations in Texas. For decades, the use of improved reclamation techniques on Luminant’s mined lands have resulted in over 31,160 ha reclaimed to forests, wildlife habitat, and pastures with productivity levels similar to those found on unmined lands. The development of new reclamation methodologies offers opportunities to further improve productivity of planted trees at Luminant’s Martin Lake Oak Hill Mine in east Texas. The conventional haulback or ‘truck shovel’ reclamation method uses haul trucks for the selective transport and placement of …

Terracing, Land Management And Agricultural Soils In The Andagua Valley Of The Southern Peruvian Andes, Blaise Murphy

Electronic Theses and Dissertations

Demographic, socio-political and climatic changes can drastically alter agricultural land management practices, affecting the availability of agriculturally relevant nutrients in the soil. This project investigates the use, reconstruction and abandonment of agricultural terraces and the implications these conditions have on agricultural soil properties of the Andagua Valley in the Western Cordillera of the Southern Peruvian Andes. During the 2016 summer field season, topsoil samples were collected from cultivated and abandoned agricultural terraces between 3229m and 3688m a. s. l. with a range of aspects and ages. Collaboration with a team of archaeologists and anthropologists gave insight into the local and …

Effects Of Silvopasture Establishment On Aqueous And Gaseous Soil N Losses At The University Of New Hampshire Organic Dairy Research Farm, Kathryn Ann Slebodnik

Honors Theses and Capstones

The expansion of local agriculture in the New England region is putting increased pressure on farmers to expand their arable land base. While clear-cutting is a traditional method of converting forested land to agriculture, it is known for having adverse ecological impacts. To minimize these impacts, farmers can create a silvopasture which incorporates a portion of the original forest canopy into pastures or crop fields. This study evaluates the impact of land-use changes for agriculture on soil nitrogen (N) retention. In particular, this study investigates the differences in soil N turnover, gaseous loss, and aqueous loss among an established forest, …

Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser

Open Access Theses

Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …

Arsenic Analysis: Comparative Arsenic Groundwater Concentration In Relation To Soil And Vegetation, Rominna E. Valentine Vecorena

Electronic Theses, Projects, and Dissertations

Arsenic (As) is a toxic semi-metallic element found in groundwater, soils, and plants. Natural and anthropogenic sources contribute to the distribution of arsenic in the environment. Arsenic’s toxic and mobile behavior is associated with its speciation ability. There are two types of arsenic available to the environment, inorganic and organic arsenic. Of the two, inorganic arsenic is more toxic to humans and more mobile in the environment. Two inorganic compounds responsible for arsenic contamination are trivalent arsenite, As (III), and pentavalent arsenate, As (V). Trivalent arsenate is considered to be more soluble, toxic, and mobile than pentavalent arsenate. Arsenic’s absorptive …

Demonstrating Short-Term Impacts Of Grazing Cover Crops On Soil Health In South Dakota, Colin Tobin

Electronic Theses and Dissertations

Grasslands have been rapidly converted to croplands over the last decade in the northern Great Plains. This conversion can reduce soil health and increase the region’s ability to pollute the Missouri and Mississippi rivers. Therefore, the need for integrated crop livestock (ICL) practices that can protect the region’s native prairies are strongly encouraged. Introducing livestock into arable cropping systems can improve nutrient cycling, soil health, and provide economic benefits. However, the detailed information about the impacts of ICL system on soil health is still lacking in the Northern Great Plains region. Therefore, the present study was conducted under a corn …

Soil Properties Affect Establishment Of Invasive Species, Celastrus Orbiculatus, In A Lower Hudson River Riparian Ecosystem, Shabana Hoosein Hoosein

Legacy Theses & Dissertations (2009 - 2024)

The Hudson River Estuary has been colonized by numerous terrestrial invasive plant species, due in part to its history of anthropogenic and natural disturbance riparian dynamics. This study investigates the spatial patterns of a widespread invasion by Oriental (or Asiatic) bittersweet (Celastrus orbiculatus Thunb.) in Schodack Island State Park, Rensselaer and Columbia Counties. The Park is home to rare species and communities, several of which are threatened by the encroachment of bittersweet. Bittersweet populations were mapped and surveyed on a fixed grid throughout the island, to determine distribution patterns. Stem densities were approximately 50% higher in sites with dredged material …

Soybean Yield And Plant Response To Phosphorus Fertilization, Rebecca L. Helget

Electronic Theses and Dissertations

Phosphorus (P) is a key limiting nutrient for soybean production in South Dakota. Soil tests have been used as a baseline indicator for plant available P and fertilizer recommendations for over a century. Plant nutrient analysis may be used to complement a soil test as a way to validate fertilizer and management practices. Soybean nutrient sufficiency ranges have only been slightly adjusted since they were published in the 1960’s. The objectives of this study were to update the soil test P and soybean plant P sufficiency level in South Dakota and to recognize implications of improper plant sampling. We also …

Long-Term Impacts Of Conservation Management Practices On Soil Carbon Storage, Stability, And Utilization Under Cotton Production In West Tennessee, Candace Brooke Wilson

Masters Theses

Biogeochemical cycling of soil carbon (C) is heavily influenced by conservation agricultural (CA) practices. This study examined SOC stability under three CA practices: reduced nitrogen (N) fertilizer application rate, cover cropping, and zero-tillage implemented for 31 years. Respiration rates measured from a 602-day incubation period were fitted to a double-pool first order exponential model of SOC decomposition. The active [respired] SOC pool showed distinct differences between applications of reduced (34N kg ha^-1 [-1]) and high fertilization rates (101N kg ha^-1) combined with tillage, and suggest that high fertilizer applications with conventional tillage allocated more C into a …

Long-Term Effects Of Alternative Residue Management Practices On Near-Surface Soil Properties And Soybean Production In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Christopher Ryan Norman

Graduate Theses and Dissertations

Adoption of management practices that maintain or increase soil organic matter (SOM), which contains 58% carbon (C) on average, may help to mitigate climate change by sequestering atmospheric C. Therefore, the main objective of this study was to determine the long-term trends in SOM, soil C and nitrogen (N), bulk density, various soil chemical properties (i.e., pH, electrical conductivity [EC], and Mehlich-3-extractable nutrients) in the top 10 cm, and soybean yield as affected by residue burning (burning and non-burning), tillage (conventional and no-tillage), irrigation (irrigated and non-irrigated), and N-fertilization/residue level (high and low) in a wheat (Triticum aestivum L.)-soybean [Glycine …

Novel Techniques To Determine Soil Evaporation Rates: Heat Pulse Probe And Automated Microlysimeter, Kashifa Rumana

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increase in world population rate has augmented the global water use in municipal, industrial, and agricultural sectors, with renewable water resources changing
very little with time. Climate change and variability, degradation of water quality as a result of industrial waste streams, animal manure and waste, application of chemicals, pesticides, pharmaceuticals, heavy metals, etc. have largely influenced the quantity and quality of soil water. Root zone water helps sustain the agricultural industry by providing much of the water needed for irrigation. It is critical to monitor the soil water availability, especially within the plant root zones. The subsurface water tends to …

Spreading The Char: The Importance Of Local Compatibility In The Diffusion Of Biochar Systems To The Smallholder Agriculture Community Context, Laura C. V. Munoz

Pomona Senior Theses

This thesis enters the context of smallholder agriculture communities in the developing world. It explores the potentials of biochar and what biochar systems could bring to the smallholder communities while simultaneously bringing environmental benefits. It then acknowledges the challenges of diffusion –the spreading of an unfamiliar innovation. It seeks to answer the question of what will make diffusion of biochar systems more successful in the smallholder context, fixating on the characteristic of compatibility as well as the role local community members can play in making a new biochar system more visible to the rest of the communities.