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Locusts are a major crop pest in many parts of the world and different species are endemic to different countries. In Latin America, the South American Locust (Schistocerca cancellata) is the predominant species found mostly in Argentina, Chile, Bolivia, Paraguay, and southern Brazil with Argentina being the most affected. Several

Locusts are a major crop pest in many parts of the world and different species are endemic to different countries. In Latin America, the South American Locust (Schistocerca cancellata) is the predominant species found mostly in Argentina, Chile, Bolivia, Paraguay, and southern Brazil with Argentina being the most affected. Several control and management practices, including biological control, have been implemented in these countries in the past to control the locusts and reduce their impact on crop and vegetation, however, effective long-term control and management practices will require a detail understanding of how the predominant locust species in this region responds to resource variation. Research has shown that there is strong evidence that locusts, and many other organisms, will actively balance dietary macronutrients (protein, carbohydrates, and lipids) to optimize growth, survival, and/or reproduction. A study by Cease et. al, 2017, on the dietary preferences of the Mongolian locust (Oedaleus asiaticus) showed that it prefers diets that are high in carbohydrates over diets that are high in protein, in this case locusts self-selected a 1:2 ratio of protein:carbohydrate. This and many other studies provide vital insight into the nutritional and feeding preferences of these locust species but the effects that this difference in protein: carbohydrate preferences has on growth, egg production, flight potential, and survival has yet to be fully explored, hence, this study investigates the effects that nitrogen fertilization of wheatgrass will have on the growth, egg production, survival, and flight muscle mass of the South American locust in a controlled, laboratory environment.
ContributorsManneh, Balanding (Author) / Cease, Arianne (Thesis director) / Overson, Rick (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
Current farming demographics in the United States indicate an aging and overwhelmingly white group of farmers, stimulating the need for engaging a younger and more diverse population. There is an opportunity to engage these populations through farm-based internship and apprenticeship programs, which are immersive programs on small-scale, sustainable farms. These

Current farming demographics in the United States indicate an aging and overwhelmingly white group of farmers, stimulating the need for engaging a younger and more diverse population. There is an opportunity to engage these populations through farm-based internship and apprenticeship programs, which are immersive programs on small-scale, sustainable farms. These programs are unique in providing hands-on training, housing, meals, and a stipend in return for labor, presenting a pathway to social empowerment. The potential outcomes of increasing diversity and inclusion in farm programs are absent from the research on the benefits of diversity and inclusion in other work environments, such as the corporate setting. This paper presents the results of a study aimed at determining levels of diversity and inclusion in United States farm-based internship programs, and the viability of these programs as an effective opportunity to engage marginalized young people in farming. The study of 13 farm owners and managers across the U.S. found that the participants are focused on fostering education and training, environmental benefits, and a sense of community in their respective programs. All participants either want to establish, or believe they currently have, an inclusive workplace on their farm, but also indicated a barrier to inclusivity in the lack of a diverse applicant pool. Future recommendations for removing that barrier and involving more young, diverse interns include increased outreach and access to these programs, the use of inclusive language, and further research.
ContributorsLascola, Dania (Co-author) / Biel, Braden (Co-author) / Cloutier, Scott (Thesis director) / MacFadyen, Joshua (Committee member) / School of International Letters and Cultures (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
This honors thesis is focused on two separate catalysis projects conducted under the mentorship of Dr. Javier Pérez-Ramírez at ETH Zürich. The first project explored ethylene oxychlorination over supported europium oxychloride catalysts. The second project investigated alkyne semihydrogenation over nickel phosphide catalysts. This work is the subject of a publication

This honors thesis is focused on two separate catalysis projects conducted under the mentorship of Dr. Javier Pérez-Ramírez at ETH Zürich. The first project explored ethylene oxychlorination over supported europium oxychloride catalysts. The second project investigated alkyne semihydrogenation over nickel phosphide catalysts. This work is the subject of a publication of which I am a co-author, as cited below.

Project 1 Abstract: Ethylene Oxychlorination
The current two-step process for the industrial process of vinyl chloride production involves CuCl2 catalyzed ethylene oxychlorination to ethylene dichloride followed by thermal cracking of the latter to vinyl chloride. To date, no industrial application of a one-step process is available. To close this gap, this work evaluates a wide range of self-prepared supported CeO2 and EuOCl catalysts for one-step production of vinyl chloride from ethylene in a fixed-bed reactor at 623 773 K and 1 bar using feed ratios of C2H4:HCl:O2:Ar:He = 3:3 6:1.5 6:3:82 89.5. Among all studied systems, CeO2/ZrO2 and CeO2/Zeolite MS show the highest activity but suffer from severe combustion of ethylene, forming COx, while 20 wt.% EuOCl/γ-Al2O3 leads to the best vinyl chloride selectivity of 87% at 15.6% C2H4 conversion with complete suppression of CO2 formation and only 4% selectivity to CO conversion for over 100 h on stream. Characterization by XRD and EDX mapping reveals that much of the Eu is present in non-active phases such as Al2Eu or EuAl4, indicating that alternative synthesis methods could be employed to better utilize the metal. A linear relationship between conversion and metal loading is found for this catalyst, indicating that always part of the used Eu is available as EuOCl, while the rest forms inactive europium aluminate species. Zeolite-supported EuOCl slightly outperforms EuOCl/γ Al2O3 in terms of total yield, but is prone to significant coking and is unstable. Even though a lot of Eu seems locked in inactive species on EuOCl/γ Al2O3, these results indicate possible savings of nearly 16,000 USD per kg of catalyst compared to a bulk EuOCl catalyst. These very promising findings constitute a crucial step for process intensification of polyvinyl chloride production and exploring the potential of supported EuOCl catalysts in industrially-relevant reactions.

Project 2 Abstract: Alkyne Semihydrogenation
Despite strongly suffering from poor noble metal utilization and a highly toxic selectivity modifier (Pb), the archetypal catalyst applied for the three-phase alkyne semihydrogenation, the Pb-doped Pd/CaCO3 (Lindlar catalyst), is still being utilized at industrial level. Inspired by the very recent strategies involving the modification of Pd with p-block elements (i.e., S), this work extrapolates the concept by preparing crystalline metal phosphides with controlled stoichiometry. To develop an affordable and environmentally-friendly alternative to traditional hydrogenation catalysts, nickel, a metal belonging to the same group as Pd and capable of splitting molecular hydrogen has been selected. Herein, a simple two-step synthesis procedure involving nontoxic precursors was used to synthesize bulk nickel phosphides with different stoichiometries (Ni2P, Ni5P4, and Ni12P5) by controlling the P:Ni ratios. To uncover structural and surface features, this catalyst family is characterized with an array of methods including X-ray diffraction (XRD), 31P magic-angle nuclear magnetic resonance (MAS-NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Bulk-sensitive techniques prove the successful preparation of pure phases while XPS analysis unravels the facile passivation occurring at the NixPy surface that persists even after reductive treatment. To assess the characteristic surface fingerprints of these materials, Ar sputtering was carried out at different penetration depths, reveling the presence of Ni+ and P-species. Continuous-flow three-phase hydrogenations of short-chain acetylenic compounds display that the oxidized layer covering the surface is reduced under reaction conditions, as evidenced by the induction period before reaching the steady state performance. To assess the impact of the phosphidation treatment on catalytic performance, the catalysts were benchmarked against a commercial Ni/SiO2-Al2O3 sample. While Ni/SiO2-Al2O3 presents very low selectivity to the alkene (the selectivity is about 10% at full conversion) attributed to the well-known tendency of naked nickel nanoparticles to form hydrides, the performance of nickel phosphides is highly selective and independent of P:Ni ratio. In line with previous findings on PdxS, kinetic tests indicate the occurrence of a dual-site mechanism where the alkyne and hydrogen do not compete for the same site.

This work is the subject of a publication of which I am a co-author, as cited below.

D. Albani; K. Karajovic; B. Tata; Q. Li; S. Mitchell; N. López; J. Pérez-Ramírez. Ensemble Design in Nickel Phosphide Catalysts for Alkyne Semi-Hydrogenation. ChemCatChem 2019. doi.org/10.1002/cctc.201801430
ContributorsTata, Bharath (Author) / Deng, Shuguang (Thesis director) / Muhich, Christopher (Committee member) / Chemical Engineering Program (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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Description
Elevated nitrate (NO3-) concentration in streams and rivers has contributed to environmental problems such as downstream eutrophication and loss of biodiversity. Sycamore Creek in Arizona is nitrogen limited, but previous studies have demonstrated high potential for denitrification, a microbial process in which biologically active NO3- is reduced to relatively inert

Elevated nitrate (NO3-) concentration in streams and rivers has contributed to environmental problems such as downstream eutrophication and loss of biodiversity. Sycamore Creek in Arizona is nitrogen limited, but previous studies have demonstrated high potential for denitrification, a microbial process in which biologically active NO3- is reduced to relatively inert dinitrogen (N2) gas. Oak Creek is similarly nitrogen limited, but NO3- concentration in reaches surrounded by agriculture can be double that of other reaches. We employed a denitrification enzyme assay (DEA) to compare potential denitrification rate between differing land uses in Oak Creek and measured whole system N2 flux using a membrane inlet mass spectrometer to compare differences in actual denitrification rates at Sycamore and Oak Creek. We anticipated that NO3- would be an important limiting factor for denitrifiers; consequentially, agricultural land use reaches within Oak Creek would have the highest potential denitrification rate. We expected in situ denitrification rate to be higher in Oak Creek than Sycamore Creek due to elevated NO3- concentration, higher discharge, and larger streambed surface area. DEA results are forthcoming, but analysis of potassium chloride (KCl) extraction data showed that there were no significant differences between sites in sediment extractable NO3- on either a dry mass or organic mass basis. Whole-reach denitrification rate was inconclusive in Oak Creek, and though a significant positive flux in N2 from upstream to downstream was measured in Sycamore Creek, the denitrification rate was not significantly different from 0 after accounting for reaeration, suggesting that denitrification does not account for a significant portion of the NO3- uptake in Sycamore Creek. Future work is needed to address the specific factors limiting denitrification in this system.
ContributorsCaulkins, Corey Robert (Author) / Grimm, Nancy (Thesis director) / Childers, Daniel (Committee member) / School of Sustainability (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Feed Your Senses is an illustrated book made to holistically communicate links between local food systems and cultural wellbeing. Food was the center of my household growing up; my mom’s love of food, cooking, and experimenting with flavors molded my palette from a young age. As I got older, I

Feed Your Senses is an illustrated book made to holistically communicate links between local food systems and cultural wellbeing. Food was the center of my household growing up; my mom’s love of food, cooking, and experimenting with flavors molded my palette from a young age. As I got older, I realized that everyone has a deeply personal relationship with their food - no matter what their upbringing. My developing interests in food took off when I started traveling and experiencing the uniqueness and vibrancy of food culture. Food became the object of every trip I took.

The summer after my Junior year, I studied abroad in Denmark and was given the opportunity to create my own research topic. My interest in Sustainability has always revolved around food, so I started thinking about ways that I could incorporate this interest with the geographical backdrop of Århus, Denmark. Food is a medium for so many uniquely human creations: celebrations, art, connection, and taste. Food is also a big driver of climate change, as the meat and agriculture industries account for more than half of all greenhouse gas emissions. However, I wanted to research more than food. I wanted to incorporate balance; a balance of local and global food systems, a balance of individual and community relationships, and a balance of science and art. I wanted to show how food is a driving force in achieving global sustainability and resilience.

After much contemplation, I began researching the connections between local food and community wellbeing in the city. I interviewed farm-to-table chefs, local farmers, farmer’s market vendors, street food vendors, and consumers on their relationships with food. The topic itself was flexible and open-ended enough so that each interviewee could relate it to their lives in a unique way. I loved the research so much that I decided to continue interviewing stakeholders in the Phoenix metropolitan area. Through the continuation of my research in Arizona, I was able to include a comparative element that offered a better perspective on the matter. I found that the history of the country itself has a significant influence on people’s mindsets and actions surrounding food and the environment. The common theme I heard from all interviewees, however, was their confidence in the power of food to unite people to one another and to the natural world.

I chose to create this illustrated book because my research experience was a whole and inseparable experience; it could never be fully expressed in words. I wanted my project to be an intellectual and visual map of my journey, inspiring the reader to go on a journey of their own. Therefore, I partnered with an undergraduate art student at Arizona State University, Sofia Reyes, to help create my vision. I shared my experiences, photos, and stories with her so that she could create the beautiful watercolor paintings that make the book so visually appealing and accessible to all demographics. The images act as a way of engaging all of our human senses, initiating a stronger connection to the material presented.

Creating this project was my favorite experience as an undergraduate, and I feel fortunate to be able to tell the stories of those intimately tied to the local food system. I am in the process of entering my book in various competitions including Writer’s Digest, Reader’s Favorites, The Food Sustainability Media Award, and The Indie Book Awards. I am also going on to publish the book through a small publishing company.
ContributorsSykes, Chloe (Author) / Cloutier, Scott (Thesis director) / MacFadyen, Joshua (Committee member) / School of Sustainability (Contributor) / School of Public Affairs (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
City managers and policy makers are increasing looking to environmental systems to provide beneficial services for urban systems. Constructed wetland systems (CWS), highly managed and designed wetland ecosystems, are being utilized to remove pollution, particularly excess nitrogen (N), from treated wastewater. Various wetland process remove N from effluent, such as

City managers and policy makers are increasing looking to environmental systems to provide beneficial services for urban systems. Constructed wetland systems (CWS), highly managed and designed wetland ecosystems, are being utilized to remove pollution, particularly excess nitrogen (N), from treated wastewater. Various wetland process remove N from effluent, such as denitrification, direct plant uptake, and soil accumulation. Emergent macrophytes provide direct uptake of N and improve conditions for microbially-mediated N processing. The role of different macrophytes species, however, is less understood and has primarily been examined in mesocosm and microcosm experiments and in mesic environments. I examined the effects of community composition on N removal and processing at the whole ecosystem scale in an aridland, constructed wetland (42 ha) through: 1) quantifying above- and belowground biomass and community composition from July 2011 \u2014 November 2012 using a non-destructive allometric technique, and; 2) quantifying macrophyte N content and direct macrophyte N uptake over the 2012 growing season. Average peak biomass in July 2011 & 2012 was 2,930 g dw/m2 and 2,340 g dw/m2, respectively. Typha spp. (Typha domingensis and Typha latifolia) comprised the majority (approximately 2/3) of live aboveground biomass throughout the sampling period. No statistically significant differences were observed in macrophyte N content among the six species present, with an overall average of 1.68% N in aboveground tissues and 1.29% N in belowground tissues. Per unit area of wetland, Typha spp. retained the most N (22 g/m2); total N retained by all species was 34 g/m2. System-wide direct plant N uptake was markedly lower than N input to the system and thus represented a small portion of system N processing. Soil accumulation of N also played a minor role, leaving denitrification as the likely process responsible for the majority of system N processing. Based on a literature review, macrophyte species composition likely influences denitrification through oxygen diffusion into soils and through the quality and quantity of carbon in leaf litter. While this study and the literature indicates Typha spp. may be the best species to promote wetland N processing, other considerations (e.g., bird habitat) and conditions (e.g., type of wastewater being treated) likely make mixed stands of macrophytes preferable in many applications. Additionally, this study demonstrated the importance of urban wetlands as scientific laboratories for scientists of all ages and as excellent stepping-off points for experiments of science-policy discourse.
ContributorsWeller, Nicholas Anton (Author) / Daniel L., Childers (Thesis director) / Grimm, Nancy (Committee member) / Turnbull, Laura (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Public Affairs (Contributor) / Graduate College (Contributor)
Created2013-05
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Description
Duckponics is an unconventional form of aquaponics that has recently been implemented by a small community in Washington State as an experiment in sustainable methods of food production. The community created the Duckponics system to test the possibility of using the waste of ducks present on the farm to fertilize

Duckponics is an unconventional form of aquaponics that has recently been implemented by a small community in Washington State as an experiment in sustainable methods of food production. The community created the Duckponics system to test the possibility of using the waste of ducks present on the farm to fertilize crop plants. This research paper examines aspects of the nitrogen cycle within this system to determine the efficacy of nitrogen removal by plants and microbes. More specifically, the research examines (1) the microbial activity occurring in selected beds of the system, (2) the ability of hydroponic grow beds to retain inorganic nitrogen, and (3) how periodic flushing of the system affects nitrogen retention. Water data was collected in all system tanks using aquarium test strips, but water samples were collected for flow injection analysis in (1) one of the grow beds, (2) the duck pond, and (3) a control bed with no plants but filled with gravel and inoculated with the same bacteria from the grow bed. Samples were then analyzed for ammonia (NH4+-N) and combined nitrite and nitrate (NOx-N) concentrations. The results show that the treatment type (control, duck pond, or grow bed) was a significant (p<0.05) predictor of NH4+-N, NOx-N, and total inorganic nitrogen (TIN) in the porewater of the treatment beds. The grow bed was found to have 100% removal of TIN, whereas the control had 0% TIN removal (195% increase). Timing of the sample in relation to the flushing events was a moderately significant predictor of TIN, NH4+-N and NOx-N in the duck pond (p = 0.07 for TIN, p = 0.12 for NH4+-N, p = 0.11 for NOx-N), with an overall decrease in TIN after flood pulses. NH4+-N concentrations at the inlet and outlet were found to be significantly different in the grow bed (p=0.037), but not the control, and moderately significantly different (p<0.15) for NOx-N and TIN in the grow bed (p=0.072 for NOx-N, p=0.075 for TIN), but significant for the control (p=0.043). These findings show evidence of nitrification in the grow bed and control, plant presence significantly contributing to nitrogen removal in the grow bed, and some hydrologic flushing of NOx-N out of the duck pond during pump cycles.
ContributorsPanfil, Daniela Kristiina (Author) / Doucette, Sonya (Thesis director) / Palta, Monica (Committee member) / Moody, Jack (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / School of Sustainability (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description

As technology has evolved over time and the U.S. population increases each year, this thesis focuses on the ways in which food production has shifted from the original farm to table to industrialized, processed food systems. Through a rationalization perspective, this research looks to the history and repercussions of industrial

As technology has evolved over time and the U.S. population increases each year, this thesis focuses on the ways in which food production has shifted from the original farm to table to industrialized, processed food systems. Through a rationalization perspective, this research looks to the history and repercussions of industrial agriculture as it has shifted over time. The term over-industrialization is used to operationalize the state of our current production methods. These methods focus extensively on the least expensive and most rapid methods to produce large yields of food products and pay no mind to ethics, respect of culture, land, or quality of products. Today, there is a shroud the corporations have placed over food production to ensure a “what we can’t see doesn’t affect us” belief system. In this way, the thesis provides insight on past, current, and future methods of manufacturing. I conclude that although plausible alternatives are present, continued research and substantial producer and consumer changes must be our main priority.

ContributorsBrodkin, Emma (Author) / Keahey, Jennifer (Thesis director) / Perkins, Tracy (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Social and Behavioral Sciences (Contributor)
Created2023-05
Description
Local food sustainability has gained significant recent attention over the past decade. Considerable research points to a host of economic, social, and environmental benefits resulting from engagement with local food systems. These benefits are more apparent when contrasted with a model in which individuals participate in larger, non-local food systems

Local food sustainability has gained significant recent attention over the past decade. Considerable research points to a host of economic, social, and environmental benefits resulting from engagement with local food systems. These benefits are more apparent when contrasted with a model in which individuals participate in larger, non-local food systems for all or most of their food sourcing. As such, this project was designed to explore possible barriers, such as lack of awareness, to engagement in local foods among Arizona State University (ASU) students on the main Tempe campus. Furthermore, this creative project aimed to evaluate how a local foods program conducted in a university dining hall might impact students’ awareness and interest in local foods served on site.
ContributorsBakeman, Taylor Melissa (Author) / Wharton, Christopher (Thesis director) / Popova, Laura (Committee member) / College of Health Solutions (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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Description
The purpose of this thesis is to imagine and predict the ways in which humans will utilize technology to feed the world population in the 21st century, in spite of significant challenges we have not faced before. This project will first thoroughly identify and explain the most pressing challenges the

The purpose of this thesis is to imagine and predict the ways in which humans will utilize technology to feed the world population in the 21st century, in spite of significant challenges we have not faced before. This project will first thoroughly identify and explain the most pressing challenges the future will bring in climate change and population growth; both projected to worsen as time goes on. To guide the prediction of how technology will impact the 21st century, a theoretical framework will be established, based upon the green revolution of the 20th century. The theoretical framework will summarize this important historical event, and analyze current thought concerning the socio-economic impacts of the agricultural technologies introduced during this time. Special attention will be paid to the unequal disbursement of benefits of this green revolution, and particularly how it affected small rural farmers. Analysis of the technologies introduced during the green revolution will be used to predict how 21st century technologies will further shape the agricultural sector. Then, the world’s current food crisis will be compared to the crisis that preceded the green revolution. A “second green revolution” is predicted, and the agricultural/economic impact of these advances is theorized based upon analysis of farming advances in the 20th century.
ContributorsWilson, Joshua J (Author) / Strumsky, Deborah (Thesis director) / Benjamin, Victor (Committee member) / Department of Supply Chain Management (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05