Digital Commons Network^™

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 …

Analyzing The Effects Of Climate Impacts In El Salvador And How They Influence Pollution, Ecosystems And Communities, Veronica Norio-Tomasino

Master's Projects and Capstones

Due to projections of rising temperatures and increased frequency and severity of extreme weather events, the rate at which climate change is impacting nations is devastating. However, developing countries and vulnerable communities are not the primary contributors to climate change, but they are at a greater risk for climate impacts by industrialized nations. As a result of increased human activity, developing nations such as El Salvador are particularly susceptible to climate-related events. Deforestation, water pollution, and human health risks are some activities that have contributed to El Salvador's vulnerability to climate change, drastically affecting rural communities suffering from multidimensional poverty. …

Effect Of Plasma Treatment On Soil Degradation Of A Biodegradable Mulch Film, Swapnil Bhattacharya

Theses

Biodegradable Mulch Films (BMFs) offer a sustainable alternative to traditional non-degradable PE mulch films. However, their slow rate of biodegradation can lead to plastics accumulation in the soil. In this study, a commercially available BMF based on polybutylene adipate co-terephthalate (PBAT) and polylactic acid (PLA) is examined. Here the effects of gliding arc plasma treatment on the bulk and surface properties, as well as its soil degradation behavior, is studied. An increase in surface oxygen containing species and hydrophilicity was observed following plasma treatment. Only a small hydrophobic recovery was noted over 30 days. No changes in the bulk polymer …

An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew

Theses and Dissertations

Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …

Understanding The Barriers To Carbon Farming On Private Lands, Harrison Naftel

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

Climate change caused by manmade greenhouse gas emissions is one of the most important challenges facing society today. Through effective management for carbon sequestration private agricultural lands could become an important part of the solution to this problem. This paper explores the many different methods that farmers, ranchers, and landowners could use to implement sequestration on their land and examines the barriers to further participation in these projects by reviewing the challenges in the world’s current carbon offset markets and offering possible solutions.

The Relationship Between Bird Species Richness And Human Appropriation Of Net Primary Productivity, Kaeli Mueller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As humans harvest increasing amounts of biomass, it is crucial to gain an understanding of how much energy is being appropriated and the impact that this could have on ecosystems and biodiversity. The primary way in which humans impact biodiversity loss is through land use change. One way of quantifying the impact of land use change is through human appropriation of net primary production (HANPP). This measurement represents the total amount of energy derived from photosynthesis that humans remove from ecosystems and appropriate for their own use. My research studies the relationship between HANPP and bird species richness at the …

Machine Learning In Agriculture: Crop Yield Prediction, Hames Sherif

Theses

The amount of crops harvested varies every year due to changes in climate and other operational as well as economic factors. Predicting the amount of crops a land will produce will result in more efficient field operations and management. At a national level, crop yield prediction can help work towards achieving food security. This, at a global level, will serve as a step towards the UN Sustainable Development Goal of Zero Hunger. This research identifies the significant factors that affect the production of staple crops in regions with desert and semi-arid climate in Africa and predict their yield. Different techniques …

Employer Perceptions Of Essential Skills Required Of Postsecondary Agriculture Students, Emily Mcclure

Theses and Dissertations

This study examined agriculture employers' perceptions of what essential skills their recent hires possess and which skills they feel their recent hires need some additional guidance in before their companies hire them. The study also asked participants what activities postsecondary agriculture students should be involved in to help develop these essential skills. The study's participants were human resource representatives from companies that participated in the Illinois State University Department of Agriculture career fair. The sample consisted of 26 subjects.The data analysis revealed significant results. Those who participated in the study came from across the United States. An overwhelming number of …

The Limits Of Financial Equity: The Federal Reserve, The Depression Of 1921, And The End Of Wilsonian Progressivism, Terril Hebert

LSU Master's Theses

The Limits of Financial Equity: The Federal Reserve, the Depression of 1921, and the End of Wilsonian Progressivism is an examination of monetary policy and centralized macroeconomic planning in the American economy during the inflationary spiral of the 1910s that culminated in the Depression of 1921. Put forward for consideration is the successful populist campaign for agricultural credit equity by the burgeoning Federal Reserve System; set against a backdrop of intentional inflation, world and domestic citizens competed against as the price and supply chain distortions perpetuated by the policing of American commerce by the Food Administration, A. Mitchell Palmer’s Department …

American Horse Power During The Great War, Hanna K. Lipsey

USF Tampa Graduate Theses and Dissertations

This dissertation charts the significant, if understudied, history of American horses during the era of World War I, from roughly 1914 to 1919. Its chapters trace how the US Army acquired, used, cared for, and ultimately demobilized horses over the course of that conflict. Beginning with their acquisition, via either an Army Horse Breeding Program or a complicated buying process, horses faced a complex introduction into military service. Life for these animals did not get any easier once they reached the European front. Although the US military was beginning to replace horses with motor trucks and tractors, horses remained central …

Factors Motivating Individuals With No School-Based Agricultural Education Background To Enter The Profession, Jenna Kay Offerman

Theses and Dissertations

Teacher recruitment and retention have been deemed a national issue across all disciplines and grade-levels in education. School-based agricultural education (SBAE) has been no exception as it has also seen a substantial decline in individuals majoring in agricultural education, entering the teaching profession, and then choosing to remain a SBAE teacher until eligible for retirement. This has resulted in a shortage of qualified SBAE teachers across the country. While alternative licensure routes have existed to help fill these teaching vacancies, it has done little to solve the long-term problem of acquiring qualified, career SBAE teachers. Agricultural education stakeholder groups have …

Effects Of Depth And Cover Crop Treatment On The Functioning And Diversity Of Soil Microbial Communities, Emily N. Hansen

Theses and Dissertations

Globally, agriculture is strained by the unpredictable effects of climate change, as well as flooding, drought, erosion, and decreases in soil fertility. To meet these challenges, agricultural systems must develop new techniques while promoting sustainable intensification practices. Cover crops can provide farmers with an off-season cash crop, while also positively impacting the soil and reducing reliance on less sustainable conventional farming practices. The objective of this research was to evaluate the impact of different cover crops on soil microbial communities at varying depths. Soils were sampled in the fall and spring from experimental plots (ISU Farm, Lexington, IL) that contained …

Toward An Eco-Cosmopolitanism: Wendell Berry And Ecowomanism In Conversation, Wade Casey

Dissertations

Agriculture, Alice Walker, bell hooks, Ecology, Theology, Wendell Berry

The Distribution Of Microplastics In Marshlands Surrounded By Agriculture Fields- Elkhorn Slough, Ca, Victoria Dickey

Capstone Projects and Master's Theses

The widespread use and subsequent reuse of plastics in the agriculture industry increases the risk of improper disposal, posing a threat to important wetland habitats. When plastics degrade, they break up into smaller pieces that pose serious threats to organisms that ingest them and to habitats they settle in. This study quantifies the estimated concentration, types, and lengths of microplastics (< 5mm plastic particles) in the marsh environments of Elkhorn Slough, California’s second largest estuary. Replicate samples of marsh soil samples were extracted from seven Elkhorn Slough marshes at varying distances from the head and the mouth of the estuary and potential sources of agricultural plastic. Using a safe and cost-effective density separation technique, microplastics were separated from the soil, identified, and counted on micro-filters using a dissecting microscope, then further analyzed with a Scanning Electron Microscope equipped with an Energy-Dispersive Spectrometer (SEM/EDS) to analyze surface microstructures and the elemental compositions of the particles. Two main microplastic morphotypes, fragments and fibers were observed. The average concentration of microplastics estimated by this study is ~1600 particles per kg of wet soil. Fragments are shorter but more abundant (making up 85% of microplastics found) than fibers and have an average length of ~85 μm and ~500 μm respectively. All microplastics found in collected samples exhibit signs of weathering, including pitting and fractures on the surface. I studied the particle size distributions of microplastics and fine-grained estuarian soil to highlight the similarities in the physical and hydrological influences controlling their distributions. This study helps to make conclusions about potential sources of microplastics to Elkhorn Slough and the Monterey Bay National Marine Sanctuary with an emphasis on California’s agriculture industry and watershed dynamics. The microplastic particle size distributions reflect hydrological influences on the suspension and deposition of microplastics in the Elkhorn Slough watershed. This finding assisted in identifying plastic sources as non-local agriculture plastics immigrating from outside of this watershed due to the removal of a natural barrier and the unique hydrological dynamics of Elkhorn Slough.

A One Health Approach: Addressing The Overuse Of Antibiotics In Agriculture, Abby Erin Anderson

Master's Projects and Capstones

Antimicrobial resistance (AMR) has emerged as one of the leading public health threats of the 21^st century (Naghavi, 2022). AMR occurs due to an evolution of bacteria, making treatments of bacterial infections less effective (Naghavi, 2022). In recent years, several publications began identifying a linkage between antibiotic use in agriculture to humans. Roughly 70% of all antibiotics in the United States are being used in animal feed (Cable, 2018). More than 2.8 million antibiotic-resistance infections occur in the United States every year- which results in roughly 35,000 deaths (CDC, 2019). A comprehensive analysis estimated nearly 1.27 million deaths globally …

Digital Agriculture In Africa: An Ethnographic Study Of Global Online Networking And Resource Mobilization On Mfangano Island, Ian James Muir Smith

Senior Theses

In one of the most isolated parts of Kenya, on an island in Lake Victoria, small-scale farmers are using newfound internet access in a unique and innovative way. New Information and Communication Technologies (ICTs) are transforming agriculture around the world, and due to a political, infrastructural, and entrepreneurial environment conducive to ICT innovation, Kenya leads the African continent in this field, known in the media as “Digital Agriculture”. In the face of the climate crisis and environmental degradation, people living on and around Mfangano Island are using self-managed volunteering platforms, crowdfunding sites, and social media in order to network with …

Assessing Virtual Free-Choice Agricultural Learning: A Mixed Methods Approach, Richard John Kennedy

Theses and Dissertations

Since the mid-19th century, agricultural museums and living history sites, first in Scandinavia and then in the United States and Canada, have provided historical, cultural, and, sometimes, scientific information about farming to visitors. Many of these visitors have been school children on field trips. Assessment of this learning, however, has been scant, particularly within the free-choice style inherent in these types of educational venues. At the same time, assessment of free-choice learning, often analyzed through the Contextual Model of Learning (Falk & Dierking 2000), has taken place at educational sites like zoos, natural history museums, and science centers. This study, …

Bioleaching Of Arsenic From Agricultural Soils, Zachary Gilstrap

All Theses

Arsenic is a ubiquitous trace metalloid. However, increasing concentrations of arsenic in soil and water is a problem the world faces due to inputs from anthropogenic sources such as mining, milling, agriculture, and coal ash. One method of remediation for these arsenic-contaminated sites is bioleaching. While it is most often used to extract metals from raw ore, it is a viable and environmentally friendly method to remove the same metals from soil. Bioleaching removes metals by cultivating living organisms such as the fungi Aspergillus niger (A.niger) or the bacterium Thiobacillus ferrooxidans (T.ferrooxidans). This research aimed to investigate A. …

Assessment Of Historical Climate Variability In Maine With Implications For Future Agricultural Productivity And Adaptation, Carly Frank

Electronic Theses and Dissertations

Climate change is a wicked problem with global impacts, one of which being the sustainability of the existing global food system. As temperatures and variability in precipitation are projected to increase, the challenges to agriculture are expected to intensify. This thesis examines the Maine historical climate record over the growing season, in combination with future projections, to assess how conditions have changed and will change with agricultural implications. In this analysis, relevant climatic variables are analyzed, and agriculture-significant measures are derived for Maine’s three climate divisions using four decades of daily and monthly gridded datasets. In addition, this thesis explores …

Manganese Geochemistry And Plant Availability In Response To Agricultural Practices, Ashleigh R. Montgomery

Masters Theses

Manganese (Mn) is an essential micronutrient for all organisms. In soils, Mn forms determine availability to plants. Most Mn research has been conducted in forest ecosystems and Mn cycling in agricultural systems is understudied. Therefore, the objective of the experiment is to understand the effect of different agricultural management strategies on Mn cycling and plant availability. First, a greenhouse experiment was conducted to determine the effect of different application rates of two Mn fertilizers (MnSO₄ and MnEDTA) on soil geochemical properties and growth of corn (Zea mays) and soybean (Glycine max). The fertilizers were applied to …

The Effect Of Plant Elicitor Peptide On Nematode Infected Soybean, Siyang Liu

Graduate Theses and Dissertations

Soybean (Glycine max), an important economic crop native to East Asia, is grown worldwide for its edible beans. Soybean plants are vulnerable to a wide range of diseases, and nematodes are among the worst pests of soybean. The southern root-knot nematode (Meloidogyne incognita) and soybean cyst nematode (Heterodera glycines) are both notable nematode pests of soybean, with the soybean cyst nematode causing more than 30% of total yield loss in the US. Numerous attempts have been made to control soybean nematodes over the past several decades, and genetic engineering technology has received a lot of attention in recent years. Plant …

Fighting Exclusion: Women In The Palm Oil Industry In Ghana Since 1957, Grace Okine

Electronic Theses and Dissertations

Women were integral to the production of palm oil in the region that is currently known as Ghana. Right from the start, they have worked in the palm oil industry as farmers, oil processors, and traders of palm fruits and oil. Yet, the story of the unique challenges and experiences of women who worked in the Ghanaian palm oil sector have largely been left out of history books. This thesis contributes to addressing this gap partly by focusing on how relevant colonial and post-colonial government policies and strategies shaped the place and roles of women who were involved in the …

Pre-Agricultural Soil Erosion Rates In The Midwestern U.S., Caroline Lauth Quarrier

Masters Theses

Soil erosion undermines agricultural productivity, limiting the lifespan of civilizations. For agriculture to be sustainable, soil erosion rates must be low enough to maintain fertile soil, as was present in many agricultural landscapes prior to the initiation of farming. However, there have been few measurements of long-term pre-agricultural erosion rates in major agricultural landscapes. We quantified geological erosion rates in the Midwestern U.S., one of the world’s most productive agricultural areas. We sampled soil profiles from 14 native prairies and measured concentrations of the cosmogenic nuclide 10Be and chemically immobile elements to calculate physical erosion rates. We used the erosion …

Is Agriculture Being Implemented In Private School Classrooms? The Impact Of Teacher Willingness And Availability Of Resources., Casey Moss

Theses and Dissertations

Agricultural literacy has been a topic of concern as most of the population have little to no understanding of agriculture, and the impact it has on society. Agricultural literacy can be defined as “having knowledge and understanding of agriculturally related scientific and technologically based concepts and processes required for personal decision making” (Meischen & Trexler, 2003, p.44). Numerous studies have been conducted to determine the significance of agricultural literacy beginning with elementary aged children and continuing through high school. The majority of studies conducted focus on public school students and teachers. This has led to a gap in the knowledge …

Plugging Into A New Age: The Impact Of Social Media Use On Undergraduate Students’ Perceptions Of Production Agriculture And Consumer Decisions, Shannon K. Allen

Theses and Dissertations

Today, 84% of young adults between the ages of 18-29 use at least one social media site (Pew Research Center, 2020) and are in the stages of emerging adulthood where they are making independent decisions for the first time (Arnett, 2000). As society becomes more technologically advanced, we become further removed from agriculture (Powell & Agnew, 2011; Dale et al., 2017). Thus, resulting in a separation between consumer and producer (Wilson & Lusk, 2020; Holt & Cartmell, 2013). This leaves the opportunity for society to turn to social media for agriculture information leading to negative perceptions of agriculture (Eyck, 2000; …

Identifying Key Stream Restoration Variables In An Agriculturally Impaired Chesapeake Bay Watershed, Julia Portmann

Masters Theses, 2020-current

The Chesapeake Bay watershed spans several states, supports diverse ecosystems, and is crucial to local economies. However, agricultural practices in this region impair water quality. The Smith Creek watershed, within the Shenandoah Valley, was designated a showcase watershed in 2010 by the United States Department of Agriculture to demonstrate the efficacy of implementing restoration projects. We sampled fifteen farms ranging from unrestored to thirty-six years since restoration. At each site, we conducted a kick-net survey for macroinvertebrates, measured canopy cover, algal density, substrate size, and bank height and angle. We identified macroinvertebrates to family and calculated the Chesapeake Basin-wide Index …

The Diffusion And Adoption Of Precision Agricultural Technologies And Practices In Six Selected Southern States, Patterson Perez Hilaire

Theses and Dissertations

Precision agriculture continues to be prevalent within row-crop production. The purpose of this study was to investigate the adoption status of precision agricultural practices among selected row-crop (soybean, wheat, corn, cotton, peanuts, and rice) producers in Alabama, Arkansas, Georgia, Louisiana, Mississippi, and Tennessee. Seventy-four percent of row-crop producers surveyed in this study had adopted precision agricultural practices in their farming operations. Eighty-three percent of respondents indicated they were using automated GPS technology such as autosteer, 66% were using manual guidance such as lightbar, 63% variable-rate prescription map, and 34% auto-sprayer boom section or nozzle control. The primary source for receiving …

Reinsmen, Roadways, And The Emerging Northern Maine Frontier, 1810-1860, Loretta Mary Risner

Electronic Theses and Dissertations

Nineteenth century reinsmen transported needed and scarce supplies, logs, people and mail in Northern Maine, on the few cut roads and rough trails before railroads arrived. Their work was the only land transportation method available to Northern Maine’s lumber camps and settlements between 1810-1860, making their labors critical to Aroostook County’s social, cultural and economic growth. Reinsmen drove teams of horses or oxen attached to a cart, wagon, dray, sleigh, sled or specialized log jumper into Maine’s forests or from Woodstock, New Brunswick and Bangor, Maine to Aroostook County. Reinsmen were once known and respected in Aroostook County for their …

Evaluating The Barriers Of Entry That Small Commercial Farmers Face And The Implications Of Such Barriers On Rural Communities, Lauren C. Chandler

Honors Theses

The research proposed in this thesis will identify the barriers of entry that

small farmers face when entering the Agricultural Industry. The proposed research will also seek to discover how having these barriers in place affects rural communities. This thesis conducts a literature review of the topic, sets the context for the research to be done, and proposes a research project to further investigate the topic. The proposed research will be done through administering a survey to stakeholders, and then interviewing a small sample of those surveyed to get a comprehensive look at the effects of agribusiness on rural communities. …

Towards Environmental Sustainability Of Nanotechnology Through Improved Evaluations Of Impact And Risk To Aquatic Species: Cross-Species Comparisons From The Laboratory And Environmentally Realistic Exposure Scenarios In The Field, Becky J. Curtis

Theses and Dissertations

Engineered nanomaterials (ENMs) are utilized in a wide variety of applications and products, including everything from toothpaste and personal care products to industries such as aerospace, defense, medicine, electronics, and agriculture. Depending on the application, release of ENMs to the environment may occur through both unintentional and deliberate routes. High surface-area-to-volume ratios make ENMs more volatile than bulk counterparts, and their small size allows translocation within biological systems that would not be possible with larger materials. These and other characteristics make ENM-biological system interactions unpredictable, creating uncertainty about their potential risks to environmental health. The purpose of this research is …