Physical Sciences and Mathematics Commons^™

Economic Feasibility Of Aquaponics In Arkansas, Leah Ashley English

Graduate Theses and Dissertations

Concerns regarding population growth and resource scarcity have led to a recent renaissance of food production research. Over the past few decades, scientists have discovered new and innovative methods for growing food that, cumulatively, may hold the key to efficiently and sustainably feeding an ever-increasing world population. One method, known as aquaponics, has shown promise as being a sustainable solution for producing food locally in all parts of the world. Although many studies have shown aquaponic food production to be technically feasible, there are relatively few studies concerning the economic feasibility of aquaponics in various regions. To determine whether aquaponics …

Modifying A Cow-Calf Biophysical Simulation Model For Analyses Of Alternative Enterprises, Jennifer L. Lutes

Graduate Theses and Dissertations

Cow-calf producers in the United States, tasked with providing beef calves for the beef industry, have had a multitude of difficulties to overcome in recent years. Producers in northwest Arkansas were negatively impacted by high hay prices coupled with low beef cattle market prices due to severe drought experienced in portions of 2010, 2011, and 2012. During this time they also faced high grain prices, due to a record low harvest, combined with portions of the corn harvest diverted from human and animal feed to ethanol production. Tight lending policies of this time, reminiscent of the housing market crash in …

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 …

Method Development For Vitamin C Quantification In Two Complex Matrices, Hannah D. Hutt

Electronic Theses and Dissertations

The following liquid chromatographic (LC) method developments and applied research studies were done using two complex food matrices, potatoes and elderberries, which are common to the state of Maine. Potatoes are Maine’s largest agricultural crop, a staple food in most U.S. households, and are, from an analytical standpoint, considered a complex matrix due to the high starch content that can be difficult to remove without degrading or removing nutrients in the process. Elderberries are an emerging crop in the U.S. because of their antioxidant and anti-viral properties and are found growing wild, throughout Maine. Elderberries are also considered a complex …

Life Cycle Assessment Of Alternative Swine Management Practices, Prathamesh Avadhut Bandekar

Graduate Theses and Dissertations

Life Cycle Assessments (LCAs) are quantitative analyses of complex systems for evaluation of impacts and risk associated with management decisions. LCAs can be effective tools for determining comparative advantages of management strategies across specific impact concern. In this study, life cycle assessments of pork production management alternatives was performed. The alternative management practices included in this study were production of entire males (boars), use of pens for gestation housing, immunocastration, production without growth promoting antimicrobials, production without growth promoting and preventive antimicrobials, and production without ractopamine. These LCAs evaluated the impact of each management strategy on greenhouse gas emission (GHG), …

Evaluation Of Control Strategies For The Spread Of Citrus Greening, Vicente Valle Martinez

Theses and Dissertations - UTB/UTPA

Huanglongbing, also known as citrus greening, is a vector-based disease in citrus (with no cure known to date) that has drastically affected the citrus production in Florida in less than a decade and has been recently detected in Texas and California. In this paper, an epidemic model of the spatial spread of the disease is implemented among commercial and residential groves by taking into consideration the diffusion patterns of the psyllid vectors. A system of differential equations resembling one for malaria infection in humans is derived to evaluate different control methods such as quarantine, treatment, removal, foliar treatment, and pest …

Defining The Terroir Of The Columbia Gorge Wine Region, Oregon And Washington, Usa Using Geographic Information Systems (Gis), Hilary Whitney

Dissertations and Theses

The Columbia Gorge Wine Region (CGWR) is an emerging wine producing area that extends for about 100km along the Columbia River in Oregon and Washington State in which the number of vineyards, wineries and physical terroir conditions have yet to be defined. To better understand the physical factors affecting Oregon and Washington wine, this project analyzes climate, topography, geology and soil at vineyards in the CGWR. This was accomplished using Geographic Information Systems, existing earth science databases and field work. The region, which includes the Columbia Gorge American Viticulture Area (AVA) and the southwest portion of the Columbia Valley AVA, …

An Approach To An Agave Problem: The Bioremediation Of Agricultural Waste By Yeast Fermentations, Joshua Michael Jarodsky

Theses and Dissertations

The agricultural waste products created by industries, such as the Tequila manufacturing industry, create thousands of tons of waste material every year. This agricultural waste often becomes an environmental and ecological problem for fields and surrounding areas. The purpose of this study is to determine the potential of using the yeast Kluyveromyces marxianus 7-1 and Kluyveromyces marxianus 8-1 to ferment the leaf waste from the harvesting of the Agave tequilana as a form of bioremediation. Fermentations (anaerobic, under constant shaking, and at room temperature) were monitored for colony forming units, pH of fermentation broth, concentration of reducing sugars, and protein …

Climate-Smart Agriculture: Farmer's Bane Or Boon?, Jeeva Mary Jacob

Dissertations, Theses, and Capstone Projects

Climate-Smart Agriculture (CSA) is one of the solutions that simultaneously address the issues of food security, climate change and agricultural productivity. It has been gaining momentum in the last five years among policy circles and development organizations have prioritized CSA interventions in developing countries around the world. In this paper, CSA interventions are examined from the small farmer's perspective and the purpose of this paper is to find out whether Climate-Smart Agriculture truly empowers the farmer in the face of climate change. Such a study emerged from the fact that in the past, agricultural interventions like the Green Revolution promised …

Insomniac Of The Soil: A Collection Of Poetry And Essays, Sarah E. Golibart

Senior Honors Projects, 2010-2019

“Insomniac of the Soil” is a homage to a landscape that has deeply informed Sarah Golibart's life and her artistic voice – the tidewater flatlands of Virginia’s Chesapeake Bay peninsula where her family lives and where Golibart has worked on farms since high school. Both her poems and essays are earthy, imagistic, and grounded – quite literally – in the soil as well as in a sensibility of ecological ethics and sustainability. “Insomniac of the Soil” is also a love song to the fervent and fallow cycles of the soil.

Sorghum Yield And Zai Holes In Goundi, Burkina Faso, Justin Gelb

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this study was to determine if there was a difference in sorghum yield between the Mossi zai hole and the Gourounsi zai hole, specifically examining the effects of manure and soil water conservation. A study field was created with six different treatments: (1) control with traditional management (no zai holes), (2) traditional management with manure, (3) Mossi zai holes with no manure, (4) Mossi zai holes with manure, (5) Gourounsi zai holes with no manure, and (6) Gourounsi zai holes with manure. Soil moisture readings were taken after each rainstorm (about weekly), soil properties were analyzed before …

Understanding Farmers’ Perceptions And The Effects Of Shea Tree Vitellaria Paradoxa Distribution In Agroforestry Parklands Of The Upper West Region, Ghana, Fahimeh Baziari

Dissertations, Master's Theses and Master's Reports - Open

Agroforestry parklands represent a vast majority of the agricultural landscape under subsistent-oriented farming in semi-arid West Africa. Parklands are characterized by the growth of well- maintained trees (e.g., shea) on cultivated fields as a result of both environmental and human influences. Shea (Vitellaria paradoxa) provides a cultural and economic benefit to the local people of Ghana, especially women. Periods between traditional fallow rotation systems have reduced recently due to agricultural development and a demand for higher production. As a result, shea trees, which regenerate during fallow periods, has decreased over the landscape. The aim of this study was …

Drivers Of Agricultural Land Use Change And Management Decisions In The Dakotas: The Influence Of Climate Change And Other Factors, Moses Luri

Electronic Theses and Dissertations

This thesis conducts a general assessment of the: main drivers of land use change; recent and projected land use patterns; and the evolution of agriculture in the Dakotas. Specifically, it determines the main motives of land use change in the Dakotas by investigating individual and joint effects of external drivers of land use change on farm operators’ decisions and also examines recent and projected agricultural land use patterns in the Dakotas. Farm operators’ perceptions about the evolution of agriculture in the Dakotas based on observed changes in their local area were also analyzed. The study region consists of 37 counties …

Subsistence Under The Canopy: Agroecology, Livelihoods And Food Sovereignty Among Coffee Communities In Chiapas, Mexico, Margarita Fernandez

Graduate College Dissertations and Theses

One of the most pressing challenges facing the world today is how to sustainably feed a growing population while conserving the ecosystem services we depend on. Coffee landscapes are an important site for research on agrifood systems because they reflect global-scale dynamics surrounding conservation and livelihood development. Within them, we find both what is broken in our global agrifood system, as well as the grassroots struggles that strive to change the system by building socio-ecologically resilient, sustainable livelihoods. Research shows that smallholder shade coffee farmers steward high biodiversity and provide essential ecosystem services. At the same time, studies in the …

Grass-Based Dairy In Vermont: Benefits, Barriers, And Effective Public Policies, Serge William Wiltshire

Graduate College Dissertations and Theses

A comprehensive literature review was undertaken in order to define and assess the sustainability and resiliency characteristics associated with grass-based and confinement dairy farming. Primarily as a result of reduced input costs, grass-based dairy farming often enhances profitability over confinement systems, especially on small farms. Further, conversion of tilled soil to permanent pasture has been shown to significantly reduce harmful sediment and nutrient transport into waterways. Perennial forage also acts as a carbon sink, curtailing or even negating a grass-based farm's carbon footprint. Finally, social benefits derived from enhanced nutrition and higher quality of life are also associated with grass-based …

An Evaluation Of Vermicompost As A Fast-Acting Nitrogen Amendment To Mitigate Nitrogen Deficiencies In Organic Vegetable Production, Peter Dalton Austin

Graduate College Dissertations and Theses

For sustained production, organic agriculture depends on plant needs being synchronized with the release of nutrients from organic amendments during decomposition within the soil. Because decomposition is strongly dependent on soil moisture and temperature, nutrient needs may not always be met as planned or synchronous with plant need. Unlike conventional agriculture, fast acting amendments are not readily available. Much of the evidence that vermicompost benefits crop production comes from studies on seed germination and production of starts in greenhouses. Yet, there is a dearth of information derived from field studies. Soil, soil and water nitrogen, plant development, and marketable yield …

Sustainable Agriculture In Vermont: Economics Of Climate Change Best Management Practices And The Complexity Of Consumer Perceptions Of Raw Milk, Alexander Paul Helling

Graduate College Dissertations and Theses

Changing weather patterns, the declining social fabric of rural communities, and economic uncertainty increasingly pose challenges to Vermont communities. The socially and environmentally embedded production practices within sustainable agriculture present a potential solution to these problems. In order to make the most of the potential benefits of these practices society must maximize their adoption. This requires an understanding of both farmer adoption of these practices and consumer perceptions of the resulting food products. This thesis contributes two original articles on sustainable agriculture through the analysis of factors driving both farmer adoption and consumer perceptions of products and practices often thought …

Using Mutli Criteria Decision Analysis To Develop Sustainability Assessment Tools: Biomass Supply Chains, Deandra Marie Perruccio

Graduate College Dissertations and Theses

Energy access remains a significant challenge in nations lacking access to resources and strong infrastructure systems, creating barriers to economic development and to increased standards of living. Small scale biomass gasification energy (BGE) systems have been developed to meet energy needs in rural areas, creating synergies between agricultural and agro-forestry systems through utilization of biomass feedstock for energy generation. The sustainability of such systems requires sophisticated planning and coordination of the biomass supply chain.

The goal of this thesis is to investigate and improve structural and process related characteristics of sustainability assessments for small scale bio-energy systems, specifically focusing on …

Biological Indicators Of Compost-Mediated Disease Suppression Against The Soilborne Plant Pathogen Rhizoctonia Solani, Lynn Fang

Graduate College Dissertations and Theses

Compost can suppress soilborne plant pathogens that cause significant damage on globally important food crops. However, reports of plant pathogen suppression are inconsistent likely because there are no established standards for feedstock material, application rate, and maturity age upon application. Excellent results can be achieved in greenhouse trials, but field applications are much less reliable. Disease suppression occurs through the activity of biocontrol organisms (direct antagonism), and general microbial competition. Biocontrol species are hypothesized to colonize the pile during the curing phase, but single species may not be as important as microbial consortia. Substrate composition during maturation may give rise …

Rural Year-Round Growing To Ameliorate A Possible Negative Effect From Climate Change, Kimberlie A. Brussa

Walden Dissertations and Doctoral Studies

The Intergovernmental Panel on Climate Change (IPCC) suggested that, as the world population grows, food and water shortages will become even more serious issues (IPPC's 2014 predictions about the future effects of climate change (CC), Year-round growing (YRG) may provide a way for communities to extend growing seasons, expand local farm systems, and provide food year round. This case study included a detailed analysis of responses from representatives of all sectors of rural Mesa County, Colorado, regarding YRG and a local food and farm plan due to CC. The case was bounded by time (6 months of data collection) which …

The Supply Chain Of Fair Trade Coffee: Challenges, Opportunities & The Future Inside A Troubled Industry, Katharine D. Lukas

Graduate College Dissertations and Theses

What started as a grassroots effort to aid tradespeople in developing nations, Fair Trade and similar certification models have, over the last sixty years, successfully established themselves as a viable alternative to conventional international trade; the ongoing growth of their market share and volume emphasize the increasing market demand for these alternatives. For coffee, Fair Trade's oldest and most established commodity, over two billion pounds was sold as certified in 2012 alone and the percentage of certified coffee continues to grow in share each year (Volcafe, 2012, Fair Trade USA 2012). As Fair Trade continues to grow, so does the …

A Framework And System For A Multi-Model Decision Aid For Sustainable Farming Practices, Kasi Bharath Vegesana

Computational Modeling & Simulation Engineering Theses & Dissertations

Decision support systems (DSS) for farmers address the need for modeling multiple processes and scenarios that affect farmer decision making. Existing DSS have various drawbacks that stop them from being deployed as decision support tools. This research proposes a multi-model simulation framework that can be used to analyze farm management practices at the crop level, individual farm level and at the community level to show the impact and alternatives for smallholder farming practices. A generic crop growth model is proposed, based on existing equations. We run sensitivity analysis on the model to identify important variables. The outputs from the crop …