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Investigation Of Parasites And Other Pathogens Associated With Eastern Wild Turkey (Meleagris Gallopavo Silvestris) Declines In Tennessee, Laura K. Horton

Doctoral Dissertations

This multi-part research project was carried out in order to investigate and address disease aspects which may be at play in the Middle Tennessee Wild Turkey population. This population has been experiencing declines since a restoration period which spanned from 1990-2000. In combined effort with Tennessee Wildlife Resource Agency, the National Wild Turkey Federation, and collaboration with other research groups at the University of Tennessee, this survey of parasites and diseases of known risk to Wild Turkeys was carried out in the study population from 2020-2023. We evaluated the prevalence of the following pathogens for three field seasons: Histomonas meleagridis …

The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba

Undergraduate Theses

An agricultural system where solar energy generation and agricultural systems are used together for mutual benefit, agrivoltaics reduces loss of water due to evaporation, particularly in drylands. Central California has faced extreme droughts, and water has become a scarce resource. However, the wide-scale use of agrivoltaics has been limited due to lack of knowledge about agrivoltaics and also the lack of funding for start-up agrivoltaics projects. Therefore, this research investigated the potential for agrivoltaics in Central California to reduce irrigation water consumption using a review of multiple crop studies using agrivoltaics to determine an optimal crop for agrivoltaics and a …

Evaluation Of Avian Use Of Agricultural Cover Crops During The Winter, Migration Stopover, And The Breeding Season In Tennessee, Brittany Panos

Masters Theses

The U.S. Department of Agriculture Natural Resources Conservation Service administers the cover crop program to provide technical and financial assistance to agricultural producers to sow herbaceous plant seeds to establish cover crops to protect agricultural fields from soil erosion during the non-growing season (late fall through spring). Soil retention and water quality benefits have been documented, but potential benefits for avian wildlife remain largely unknown. I used line-transect avian and vegetation surveys to examine use of cover crop fields by birds during the non-breeding period (winter), migration, and the breeding season. I compared avian use of cover crop fields with …

Breaking The Loop: Strategies For Fighting Climate Change On U.S. Farms, Ashley Barry

Honors Capstones

Climate change is an increasingly urgent area of research due to the hardships it causes for lands and communities across the globe. Specifically in regard to the United States (U.S.), climate change has many concerning implications on our agricultural system. Increased weather hazards, decreased crop production, and drought are just a few of the hardships American farmers are facing in their fight to keep their farms alive and feed their communities, despite a rapidly changing climate. This study investigates how farmers can fight and prevent climate change through the use of specific mitigation and adaptation strategies on their farms. Semi- …

The Influence Of Framing And Recent Experience On Farmer Choices In Experimental Games Depicting Risk-Reducing Agricultural Technologies, Ana Maria Ospina Tobar

Electronic Theses and Dissertations

Climate change is a major threat to food security, particularly in low and middle-income countries that are highly dependent on staple crops for subsistence. The vulnerability of staple crops, like maize, in the face of climate change, is increasing due to the increasing frequency of droughts. This thesis aims to evaluate two mechanisms through which farmers may be more willing to adopt new technologies that increase their resilience to climate change: First, I evaluate the effectiveness of a new virtual maize farming game as a learning tool to teach farmers about the outcomes they could obtain under different weather events …

Determining The Impact Of Post-Harvest Water Management On Chironomid Abundance, Agrochemical Biomass And Potential Trophic Biomagnification, Mason Thomas

Theses and Dissertations

Agriculture has diminished shorebirds’ natural habitat in the Mississippi Alluvial Valley. Remaining natural stopover sites are supplemented with agricultural fields during the fall and winter. This study evaluates the impact of 4 different post-harvest water management strategies on shorebird food abundance and potential agrochemical biomagnification. Chironomid samples estimated abundance, biomass, and chironomid agrochemical concentration in each field. A risk assessment of agrochemical biomagnification to shorebirds was made across all treatments. Of treatments represented on all study sites, winter treatment had greatest chironomid abundance and biomass. Models indicated that days since flood initiation, start date, and temperature are significant predictors of …

Practical Improvements For Pivot And Surface Irrigation, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Irrigation is critical to meeting global food and fiber demands. Optimizing agricultural irrigation may help sustain production levels, while reducing its demand for water. This research evaluated precision sprinklers and drip irrigation for pivots, five pivot track mitigation tools, three scientific irrigation scheduling (SIS) methods, sensors for surface irrigation cutoff, and automating surface systems to implement surge irrigation. With pivots and surface irrigation being the most common methods for irrigation in the West, small improvements from these tools could result in significant water savings.

Low energy precision application (LEPA) sprinklers and mobile drip irrigation (MDI) were tested on two pivots. …

Exploring Beaver-Facilitated Restoration In Grassland Channelized Streams, Jessica L. Sikora

Graduate Research Theses & Dissertations

Freshwater streams provide vital ecosystem services, but their ecological function is gravely impacted by agricultural practices especially in grassland ecosystems. Though there is evidence that the re-introduction of beavers can help restore the ecological function of streams, little is known about their restorative impacts in grasslands. At Nachusa Grasslands Preserve in Franklin Grove, IL, we investigated the presence and impact of beaver dams on their waterways. With increasing beaver dam volume, we found an increase in sediment retention and less sediment retention with increasing beaver dams upstream from a dam. Though we did not find evidence that beaver dam volume …

Groundwater Governance And Agricultural Sustainability: Examining Farmer Interactions With California’S Sustainable Groundwater Management Act, Zachary Matthew Goldstein

Graduate College Dissertations and Theses

Climate change has exacerbated groundwater depletion globally, and policymakers have struggled to effectively manage groundwater resources. California enacted the Sustainable Groundwater Management Act (SGMA) in 2014 to restore groundwater to sustainable levels.

The first paper of this thesis examines the drivers associated with uptake of groundwater conservation practices in agriculture. While a rich body of research has explored farmers’ conservation practice adoption, understanding of groundwater conservation practices is more limited. This study explores how information sources influence the actual and intended adoption of groundwater management practices in California. Using survey data from farmers (n = 553) in three largely agricultural …

Application Of The Fine Sediment Biotic Index To Three Drain Tiled And Ditched Agricultural Systems In Southern Minnesota, Bailey Sanders

All Graduate Theses, Dissertations, and Other Capstone Projects

Artificial drainage is a common agricultural management technique in the United States used to remove excess water from poorly drained soils. Approximately 22.48 million hectares of crop land are drain-tiled in the United States, providing long-term economic benefits to farmers. However, artificial drainage increases sediment transport in agricultural watersheds, which can degrade aquatic systems, destroy habitats, and limit biological diversity. Biotic indices based on benthic macroinvertebrates are commonly used to assess surface water quality, but recent studies show potential in developing sediment biotic indices using benthic macroinvertebrates to estimate fine sediment in streams. The objective of this study was to …

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. …

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 …

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 …

Watershed Management For Nutrient Control In Taylor Creek And Nubbins Slough, Florida, Rachael Z. Cooper

USF Tampa Graduate Theses and Dissertations

Despite efforts to improve water quality within the watershed since the 1970s, harmful algal blooms (HABs) still occur within Lake Okeechobee (LO). HABs are harmful to the people, the ecosystem, and the economy dependent on the lake. Taylor Creek Nubbins Slough (TCNS) is a subwatershed of the lake, contributing to a large percentage of the nutrient loading. Due to the size and complexity of LO’s watershed, two smaller basins within the TCNS subwatershed were selected to evaluate the following research questions: (1) How do water quality trends contrast between two basins? (2) How do nutrient load and treatment within the …

Policy Sustainability Issues: Case Study Of Cassava Farmers In Ikorodu. Lagos, Nigeria, Medinat Oluwatoyin Adetunji

Walden Dissertations and Doctoral Studies

The inconsistency and lack of continuity of Nigeria's agricultural policies impact the cassava sector. Despite being the world's biggest producer, the country is yet to benefit from the advantage due to a lack of sustainable growth. The situation manifests in terms of low productivity, low production level, and poor income to the farmers. The purpose of this qualitative study was to investigate the experiences and perceptions of the cassava farmers on cassava policies and the effect on their income and livelihoods in the Ikorodu local government of Lagos State. This qualitative study adopted a case study research design using participatory …

Soil Resilience And Arbuscular Mycorrhizal Fungi: How Fungi Can Inform Climate Change Mitigation And Adaptation In Maya Milpa Management, Courtney Mathers

Electronic Theses and Dissertations

In Mexico’s state of Yucatán, climate change impacts like prolonged and less predictable dry season length are manifesting as threats to agricultural production and food security. Nearly two thirds of Yucatán’s population is indigenous, many of whom live in rural communities that rely on rainfed subsistence agriculture (INEGI 2015). Ensuring sufficient food production in the face of climate change relies on the quality of agricultural soils. With both mismanagement of agricultural soils and climate change posing as threats to food production in Mexico, soil management practices that increase a soil quality should be identified and promoted. The primary objective of …

Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau

Graduate Theses and Dissertations

Cover crops are a widely considered practice to improve soil health in the form of erosion control, organic matter additions, and improving water-holding capacity. Despite the well-documented benefits, little is known about the effect of cover crops on soils in the Lower Mississippi River Valley (LMRV), an area historically dominated by intensive cultivated agriculture, with soils prone to erosion, and unsustainable aquifer withdrawals for irrigation. The main objective of this study was to evaluate the effects of cover crops [with cover crops (CC) and without cover crops (NCC)] on near-surface soil physical/chemical- and infiltration-related properties, aggregate stability, and water retention. …

Long-Term Changes In Soil Surface Properties As Affected By Management Practices In A Wheat-Soybean, Double-Crop System, Machaela Morrison

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Long-term agricultural sustainability and productivity are controlled by the integrative effects of different management practices on the soil. Many Arkansas producers use the double-crop system to grow soybeans [Glycine max (L.) Merr] and wheat (Triticum aestivum L.). Studying combinations of different, non-traditional, alternative agricultural techniques may help producers better understand the long-term implications of various management practice options on sustainability and productivity. The objective of this study was to evaluate the effects of agricultural management practices, including residue level, tillage, irrigation, and burning, and soil depth on the change in various soil properties from 2010 to 2020 in …

Estimation Of Spatial Change In Cropland Area And Evaluation Of Irrigation Performance In Imperial Valley Using Remotely Sensed Data, Usha Poudel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Imperial Valley (IV) in the US is an extensively irrigated agricultural region, which includes multiple crops changing on an annual and semiannual basis. The valley is facing grave concerns about water management due to its semi-arid environment, water intensive crops, and limited water supply. A simple, inexpensive, and repeatable method to detect changes in cropping patterns may assist irrigation managers to understand crop diversification and associated consumptive use. In addition, a spatial assessment of existing water irrigation system performance and productivity is crucial to benchmark and improve current water management strategies. This thesis estimates the spatial pattern of change …

A Study Of The Social, Cultural, And Environmental Influences On Appalachian Agriculture, Morganne May

Senior Theses

Appalachia, despite its rich history and abundant biological and cultural diversity, is commonly associated with a generalized notion of ignorance, resistance to progress, and "backwardness." This study aims to shed light on the socioeconomic, cultural, and environmental influences which have shaped the present food systems of Appalachia through a review of relevant literature. This history provides the necessary context to strategize a region-specific, socioeconomically and environmentally sustainable food system moving forward.

Sediment Nutrient Dynamics In Fondriest Agricultural Settling Pond, Marie Grace Bezold

Browse all Theses and Dissertations

Excess loading of nitrogen (N) and phosphorus (P) is a serious global problem and has numerous negative impacts on water quality of aquatic ecosystems including eutrophication, harmful algal blooms, and hypoxia. Anthropogenic activities (such as the Haber-Bosch process, burning of fossil fuels, sewage treatment, and manure reuse) have led to excess N loading to aquatic systems. Sediment N dynamics were examined from Oct 2019 – Oct 2020 in an agricultural settling pond connected to a constructed wetland adjacent to an agricultural field. Intact sediment cores were amended with 15N for continuous-flow incubations to measure denitrification and N fixation rates, as …

Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri

Graduate College Dissertations and Theses

As the ripple-effects of a changing climate shape our planet, understanding relationships between agriculture and climate change is critical. With agricultural practices shaping soils on over a third of the earth’s land surface, the soils and lands where food is produced are integral grounds for examining these relationships. While not all humans practice agriculture in similar or damaging ways, nevertheless, dominant agricultural practices are displacing beings and ecosystems and perturbing global nutrient cycles across the planet. These entwined imbalances of dominance and nutrients result in flows of excess nitrogen, phosphorus, and carbon that are responsible for nearly three-fourths of the …

Condition And Function Of Red River Valley Streams Receiving Nutrients From Human Activities In Manitoba, Canada, Kristin J. Painter

Electronic Thesis and Dissertation Repository

Small tributary streams are conduits between the landscape and larger waterbodies and provide important ecosystem services including assimilation of nutrients from human activities which may be protective of downstream waterbodies. In the Red River Valley (RRV), Manitoba, numerous nutrient sources including agricultural runoff, livestock manure, and municipal wastewater effluent, have been attributed to the eutrophication of Lake Winnipeg and thus require targeted management to prevent loss of nutrients from land to lake. However, linkages between land-based nutrient-producing human activities in the RRV and the ecological status of the tributaries remain poorly understood. Furthermore, the proportional contribution of each source of …

Agricultural Conservation Decision-Making Under Environmental Risk And Uncertainty On The California Central Coast, Diego Rivera

Master of Science in Environmental Sciences and Management Projects

Global climate change is a process that is, in part, caused by agricultural practices, and will adversely affect agricultural operations, especially vineyards. The objective of this project is to determine how viticulturalists in Paso Robles, California view global climate change and how they use conservation practices that combat climate change and prepare for the associated negative effects. Interviews were conducted with vineyard advisors and managers to determine what general risks associated with wine grape production exist for their operations, and whether wine advisors and producers perceive global climate change to be one of those risks. The interview responses were then …

Influences Of Conservation Farming Practice Adoption Amongst Vineyards On The Central Coast Of California, Jazlyn Guerrero

Master of Science in Environmental Sciences and Management Projects

Farming practices will require changes to reduce crop sensitivity to climate change, which is projected to cause extreme heat events, variable precipitation, extended periods of drought, and increasing presence of pest and disease. Conservation agricultural practices build farm resiliency to climate impacts by improving soil health, reducing erosion and sediment runoff, and improving water infiltration. Literature on the adoption of conservation agriculture practices find no universal factors that indicate adoption of practices but suggest that the adoption of practices can be better understood by investigating practices specific variables and farm level characteristics and their implications on adoption. Our objective is …

The Conservation And Population Ecology Of The Imperiled Crawfish Frog (Lithobates Areolatus) In Human-Altered Landscapes, Chelsea Shannon Kross

Graduate Theses and Dissertations

The Crawfish Frog (Lithobates areolatus) is an imperiled amphibian currently experiencing severe declines across its range. As a species with unique habitat requirements that is threatened by habitat loss, understanding their status across the landscape and how they respond to environmental stressors is key to developing effective conservation strategies that maintain and expand viable populations. We used a combination of observational, experimental, and theoretical approaches to understand the status of Crawfish Frog populations in Northwest Arkansas (NWA), their individual and population-level response to human-induced changes in vegetation surrounding breeding wetlands, and the effects of fire management on larval development within …

Irrigation Design In Montana: Accommodating Varying Water Accessibility Across The Continental Divide., John Garrett Lampson

Biological and Agricultural Engineering Undergraduate Honors Theses

The design work performed in this project was conducted over two summers (2018, 2019) of internship experience with the Natural Resources Conservation Service (NRCS) across the state of Montana. The first summer’s design work was based out of Glendive, MT, in Dawson County, approximately 50 kilometers from the North Dakota border. The second summer was in Missoula, MT, in Missoula County, near the Idaho border. The two areas differ significantly in topography, weather, and water availability with the main separating geographic influence being the Rocky Mountains.

This paper focuses on the design process and requirements for two farms located outside …

Projected Impacts Of Climate Change On Risk Of Spring Frost And Fire Blight For Malus Domestica, Paul J. Racco

Theses and Dissertations

The impact of climate change is projected for apple phenology, frost attrition, and fire blight risk under the highest emissions scenario through the 21st century.

Evaluation Of The Relationship Between Land Use And Water Quality In Kittitas County, Wa, Lindsay Schulz

All Master's Theses

Water in Kittitas County is extremely valuable since it supports farming, recreation, and cultural activities, as well as environmental processes and a diversity of biological life while providing many ecosystem services. However, land conversions required by agricultural and urban land uses can negatively impact water quality and the biological function of the stream. I studied how forested, agricultural, and urban land use affect six streams. Fourteen sites were sampled, once each in July, August, and September 2019. Land use was calculated as a percentage of forested, agricultural, and urban land use within a 100-m buffer of the stream, upstream of …

Viability Of Wetland Crops For Use In Treatment Wetlands: Nitrogen Removal From Water And Production Of Food, Andrew Denson Corder

Theses and Dissertations

Treatment wetlands are used to treat wastewater from a variety of sources, but their functionality depends on the macrophytes present therein. To better understand the viability of wetland macrophytes both as sources of food and as agents of nitrogen removal from wastewater, this study quantified plant growth, food production, and nitrogen removal capacity of three common wetland crops as well as three locally dominant graminoid species in a variety of relevant ecological contexts. All six plant species and a control were grown over a ten-week period in three related experiments: (1) under three moisture regimes, (2) with or without competition …