Matching Items (85)
Description

The debate around genetic engineering has permeated society for decades. A crucial aspect of this debate is the containment of genetically engineered organisms. This project outlines the three types of biocontainment and the conclusions drawn about each in the form of policy briefs. These briefs utilize case studies to sketch

The debate around genetic engineering has permeated society for decades. A crucial aspect of this debate is the containment of genetically engineered organisms. This project outlines the three types of biocontainment and the conclusions drawn about each in the form of policy briefs. These briefs utilize case studies to sketch an overview of the current biocontainment paradigm in the United States. In addition, there is a brief discussing the major conclusions drawn from the case studies, as well as a brief containing useful definitions.

ContributorsDanciu, Mark (Author) / Frow, Emma (Thesis director) / Vogel, Kathleen (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor)
Created2023-05
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Description
Necrotic enteritis (NE) is caused by type A strains of the bacterium Clostridium perfringens, leading to an estimated 2 billion dollar global economic loss in the poultry industry annually. Traditionally, NE has been effectively controlled by antibiotics added to the diet of poultry. Concerns about increasing antibiotic resistance of poultry

Necrotic enteritis (NE) is caused by type A strains of the bacterium Clostridium perfringens, leading to an estimated 2 billion dollar global economic loss in the poultry industry annually. Traditionally, NE has been effectively controlled by antibiotics added to the diet of poultry. Concerns about increasing antibiotic resistance of poultry and human based pathogens have led to the consideration of alternative approaches for controlling disease, such as vaccination. NE causing strains of C. perfringens produce two major toxins, α-toxin and NetB. Immune responses against either toxin can provide partial protection against NE. We have developed a fusion protein combining a non-toxic carboxy-terminal domain of the α-toxin (PlcC) and an attenuated, mutant form of NetB (NetB-W262A) for use as a vaccine antigen to immunize poultry against NE. We utilized a DNA sequence that was codon-optimized for Nicotiana benthamiana to enable high levels of expression. The 6-His tagged PlcC-NetB fusion protein was synthesized in N. benthamiana using a geminiviral replicon transient expression system. The fusion protein was purified by metal affinity chromatography and used to immunize broiler birds. Immunized birds produced a strong serum IgY response against both the plant produced PlcC-NetB protein and against bacterially produced His-PlcC and His-NetB. However, the PlcC-NetB fusion had antibody titers four times that of the bacterially produced toxoids alone. Immunized birds were significantly protected against a subsequent in-feed challenge with virulent C. perfringens when treated with the fusion protein. These results indicate that a plant-produced PlcC-NetB is a promising vaccine candidate for controlling NE in poultry.
ContributorsHunter, Joseph G (Author) / Mason, Hugh (Thesis advisor) / Mor, Tsafrir (Committee member) / Blattman, Joseph (Committee member) / Arizona State University (Publisher)
Created2018
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Description
The United States Department of Agriculture provides requirements for a farm operation to become certified organic, but how do these regulations influence nutrient management on organic farms? There is insufficient evidence to show if the current regulations on nutrient sourcing and application are feasible and effective. An online survey was

The United States Department of Agriculture provides requirements for a farm operation to become certified organic, but how do these regulations influence nutrient management on organic farms? There is insufficient evidence to show if the current regulations on nutrient sourcing and application are feasible and effective. An online survey was administered to owners and operators of organic farms. Survey respondents were offered a free soil test as an incentive to participate and to compare their practices and soil quality. Assessing the current nutrient management under organic regulations provides information to help assess the sustainability of their nutrient management practices. Early data suggest that organic farmers may most often be overapplying and creating legacy sources with this key resource.
ContributorsBonham, Emma Eileen (Author) / Muenich, Rebecca (Thesis advisor) / Zanin, Alaina (Committee member) / Williams, Clinton (Committee member) / Arizona State University (Publisher)
Created2022
Description
Since the 20th century, Arizona has undergone shifts in agricultural practices, driven by urban expansion and crop irrigation regulations. These changes present environmental challenges, altering atmospheric processes and influencing climate dynamics. Given the potential threats of climate change and drought on water availability for agriculture, further modifications in the agricultural

Since the 20th century, Arizona has undergone shifts in agricultural practices, driven by urban expansion and crop irrigation regulations. These changes present environmental challenges, altering atmospheric processes and influencing climate dynamics. Given the potential threats of climate change and drought on water availability for agriculture, further modifications in the agricultural landscape are expected. To understand these land use changes and their impact on carbon dynamics, our study quantified aboveground carbon storage in both cultivated and abandoned agricultural fields. To accomplish this, we employed Python and various geospatial libraries in Jupyter Notebook files, for thorough dataset assembly and visual, quantitative analysis. We focused on nine counties known for high cultivation levels, primarily located in the lower latitudes of Arizona. Our analysis investigated carbon dynamics across not only abandoned and actively cultivated croplands but also neighboring uncultivated land, for which we estimated the extent. Additionally, we compared these trends with those observed in developed land areas. The findings revealed a hierarchy in aboveground carbon storage, with currently cultivated lands having the lowest levels, followed by abandoned croplands and uncultivated wilderness. However, wilderness areas exhibited significant variation in carbon storage by county compared to cultivated and abandoned lands. Developed lands ranked highest in aboveground carbon storage, with the median value being the highest. Despite county-wide variations, abandoned croplands generally contained more carbon than currently cultivated areas, with adjacent wilderness lands containing even more than both. This trend suggests that cultivating croplands in the region reduces aboveground carbon stores, while abandonment allows for some replenishment, though only to a limited extent. Enhancing carbon stores in Arizona can be achieved through active restoration efforts on abandoned cropland. By promoting native plant regeneration and boosting aboveground carbon levels, these measures are crucial for improving carbon sequestration. We strongly advocate for implementing this step to facilitate the regrowth of native plants and enhance overall carbon storage in the region.
ContributorsGoodwin, Emily (Author) / Eikenberry, Steffen (Thesis director) / Kuang, Yang (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2024-05
Description

The Kilombero Valley lies at the intersection of a network of protected areas that cross Tanzania. The wetlands and woodlands of the Valley, as well as the forest of surrounding mountains are abundant in biodiversity and are considered to be critical areas for conservation. This area, however, is also the

The Kilombero Valley lies at the intersection of a network of protected areas that cross Tanzania. The wetlands and woodlands of the Valley, as well as the forest of surrounding mountains are abundant in biodiversity and are considered to be critical areas for conservation. This area, however, is also the home to more than a half million people, primarily poor smallholder farmers. In an effort to support the livelihoods and food security of these farmers and the larger Tanzanian population, the country has recently targeted a series of programs to increase agricultural production in the Kilombero Valley and elsewhere in the country. Bridging concepts and methods from land change science, political ecology, and sustainable livelihoods, I present an integrated assessment of the linkages between development and conservation efforts in the Kilombero Valley and the implications for food security.

This dissertation uses three empirical studies to understand the process of development in the Kilombero Valley and to link the priorities and perceptions of conservation and development efforts to the material outcomes in food security and land change. The first paper of this dissertation examines the changes in land use in the Kilombero Valley between 1997 and 2014 following the privatization of agriculture and the expansion of Tanzania’s Kilimo Kwanza program. Remote sensing analysis reveals a two-fold increase in agricultural area during this short time, largely at the expense of forest. Protected areas in some parts of the Valley appear to be deterring deforestation, but rapid agricultural growth, particularly surrounding a commercial rice plantation, has led to loss of extant forest and sustained habitat fragmentation. The second paper focuses examines livelihood strategies in the Valley and claims regarding the role of agrobiodiversity in food security.

The results of household survey reveal no difference or lower food security among households that diversify their agricultural activities. Some evidence, however, emerges regarding the importance of home gardens and crop diversification for dietary diversity. The third paper considers the competing discourses surrounding conservation and development in the Kilombero Valley. Employing q-method, this paper discerns four key viewpoints among various stakeholders in the Valley. While there are some apparently intractable distinctions between among these discourses, consensus regarding the importance of wildlife corridors and the presence of boundary-crossing individuals provide the promise of collaboration and compromise.

ContributorsConnors, John Patrick (Author) / Turner, Billie Lee (Thesis advisor) / Eakin, Hallie (Committee member) / Myint, Soe (Committee member) / Arizona State University (Publisher)
Created2015
Description
Agricultural supply chains are complex systems which pose significant challenges beyond those of traditional supply chains. These challenges include: long lead times, stochastic yields, short shelf lives and a highly distributed supply base. This complexity makes coordination critical to prevent food waste and other inefficiencies. Yet, supply chains of fresh

Agricultural supply chains are complex systems which pose significant challenges beyond those of traditional supply chains. These challenges include: long lead times, stochastic yields, short shelf lives and a highly distributed supply base. This complexity makes coordination critical to prevent food waste and other inefficiencies. Yet, supply chains of fresh produce suffer from high levels of food waste; moreover, their high fragmentation places a great economic burden on small and medium sized farms.

This research develops planning tools tailored to the production/consolidation level in the supply chain, taking the perspective of an agricultural cooperative—a business model which presents unique coordination challenges. These institutions are prone to internal conflict brought about by strategic behavior, internal competition and the distributed nature of production information, which members keep private.

A mechanism is designed to coordinate agricultural production in a distributed manner with asymmetrically distributed information. Coordination is achieved by varying the prices of goods in an auction like format and allowing participants to choose their supply quantities; the auction terminates when production commitments match desired supply.

In order to prevent participants from misrepresenting their information, strategic bidding is formulated from the farmer’s perspective as an optimization problem; thereafter, optimal bidding strategies are formulated to refine the structure of the coordination mechanism in order to minimize the negative impact of strategic bidding. The coordination mechanism is shown to be robust against strategic behavior and to provide solutions with a small optimality gap. Additional information and managerial insights are obtained from bidding data collected throughout the mechanism. It is shown that, through hierarchical clustering, farmers can be effectively classified according to their cost structures.

Finally, considerations of stochastic yields as they pertain to coordination are addressed. Here, the farmer’s decision of how much to plant in order to meet contracted supply is modeled as a newsvendor with stochastic yields; furthermore, options contracts are made available to the farmer as tools for enhancing coordination. It is shown that the use of option contracts reduces the gap between expected harvest quantities and the contracted supply, thus facilitating coordination.
ContributorsMason De Rada, Andrew Nicholas (Author) / Villalobos, Jesus R (Thesis advisor) / Griffin, Paul (Committee member) / Kempf, Karl (Committee member) / Wu, Teresa (Committee member) / Arizona State University (Publisher)
Created2015
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Description
In recent decades animal agriculture in the U.S. has moved from small, distributed operations to large, Concentrated Animal Feeding Operations (CAFOs). CAFOs are defined by federal regulations based on animal numbers and confinement criteria. Because of the size of these operations, the excessive amount of manure generated is typically stored

In recent decades animal agriculture in the U.S. has moved from small, distributed operations to large, Concentrated Animal Feeding Operations (CAFOs). CAFOs are defined by federal regulations based on animal numbers and confinement criteria. Because of the size of these operations, the excessive amount of manure generated is typically stored in lagoons, pits, or barns prior to field application or transport to other farms. Water quality near CAFOs can be impaired through the overflow of lagoons, storm runoff, or lagoon seepage. Assessing water quality impacts of CAFOs in a modeling framework has been difficult because of data paucity. A CAFO lagoon module was developed to assess lagoon overflow risk, groundwater quality, and ammonia emissions of a dairy lagoon. A groundwater quality assessment of a Dairy Lagoon in Lynden Washington was used to calibrate and validate the groundwater quality model. Groundwater down stream of the lagoon was negatively impaired. The long-term effects of this lagoon on water quality were explored as well as the effectiveness of improving the lagoon lining to reduce seepage. This model can be used to improve understanding of the impacts of CAFO lagoon seepage and develop sustainable management practices at the watershed scale for these key components of the agricultural landscape.
ContributorsRudko, Noah (Author) / Muenich, Rebecca (Thesis advisor) / Garcia, Margaret (Committee member) / Xu, Tianfang (Committee member) / Arizona State University (Publisher)
Created2021
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Description

In the Southwestern United States, climate change poses challenges to reliable water access due to droughts, wildfires, and urban development. Arizonan farmers are faced with unpredictable precipitation, muddled legal water rights, and outdated equipment to irrigate their land. Located in Northern Arizona, Verde Valley residents and stakeholders are challenging the

In the Southwestern United States, climate change poses challenges to reliable water access due to droughts, wildfires, and urban development. Arizonan farmers are faced with unpredictable precipitation, muddled legal water rights, and outdated equipment to irrigate their land. Located in Northern Arizona, Verde Valley residents and stakeholders are challenging the way the Verde River water is managed through collaboration, partnerships, and technical changes to water infrastructure. Through interviews conducted with various stakeholders involved in the Verde River ditch irrigation system, ranging from water users to nonprofit organizations, this paper identifies sociotechnical tinkering as an important aspect of maintaining agricultural operations along the river amid political tensions, social relations, and climate change. Through interviews and analysis, this paper further contributes to the relatively new discourse on the concept of sociotechnical tinkering by proving its existence and its subsequent effectiveness in the Verde Valley. Using statements made by respondents, the paper argues that sociotechnical tinkering helps manage resources through political and social relations.

ContributorsNichols, Claire (Author) / Wutich, Amber (Thesis director) / Quimby, Barbara (Committee member) / Barrett, The Honors College (Contributor) / Environmental and Resource Management (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2021-12
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Description
Urban agriculture includes both farming and gardening, typically in a community format, in urban areas. Agrihoods are neighborhoods centered around food production and they are becoming more popular residential areas as the local food movement grows. Agritopia is one of these agrihoods; located in Gilbert, Arizona, it contains both an

Urban agriculture includes both farming and gardening, typically in a community format, in urban areas. Agrihoods are neighborhoods centered around food production and they are becoming more popular residential areas as the local food movement grows. Agritopia is one of these agrihoods; located in Gilbert, Arizona, it contains both an urban farm and a community garden. Agritopia is oft cited for being an exemplary agrihood. This thesis uses Agritopia as a case study for exploring the challenges associated with urban agriculture in the Sonoran Desert.
Most urban agriculture sites experience challenges related to sustainability, but in the Sonoran Desert, even more challenges arise as a result of a unique climate, soil conditions, intense storms, and water scarcity. The objective of this project was to obtain information on common barriers to urban agriculture in the Sonoran Desert, as well as ways to overcome these barriers that will be made public for the purpose of improving sustainability of similar agriculture projects. I used interviews with gardeners and farm staff as my primary research method to gain insight to these barriers and solutions, and I coded their responses relating to challenges according to frequency mentioned. Using my findings, I compiled a thorough list of recommendations that urban agriculture projects in the Sonoran Desert or in similar climatic areas can use to achieve greater success and sustainable outcomes.
ContributorsAnglin, Paige Elizabeth (Author) / Eakin, Hallie (Thesis director) / Norton, Susan (Committee member) / School of Sustainability (Contributor, Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
To successfully launch and maintain a long-term colony on Mars, Martian agricultural systems need to be capable of sustaining human life without requiring expensive deliveries from Earth. There is a need for more studies on this topic to make this a feasible mission. This thesis aims to study from a

To successfully launch and maintain a long-term colony on Mars, Martian agricultural systems need to be capable of sustaining human life without requiring expensive deliveries from Earth. There is a need for more studies on this topic to make this a feasible mission. This thesis aims to study from a high level one such agricultural system, specifically examining the requirements and flow of Nitrogen, Phosphorus and Potassium required to sustain a given human colony size. We developed a Microsoft Excel based model that relates human nutritional needs to the amount available in food crops and in turn the amount of Martian soil required for agriculture. The model works by inputting the number of humans, and then utilizing the built-in calculations and datasets to determine how much of each nutrient is needed to meet all nutritional needs of the colony. Using that information, it calculates the amount of plants needed to supply the nutrition and then calculates the amount of nutrients that would be taken from the soil. It compares the Martian regolith to the nutrient uptake, accounting for inedible biomass from the plants and human waste that can be added to the regolith. Any deficiencies are used to determine if and how much fertilizer should be added to the system initially and over time. Using the total amount of plants and the number of harvests, the amount of Martian land required for sustaining the colony is computed. These results can be used as a building block to enable the successful design of an agricultural system on Mars.
ContributorsGarland, Michael (Co-author) / Zinke, Sarah (Co-author) / Muenich, Rebecca (Thesis director) / Perreault, Francois (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05