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- Creators: Schumann, Robert, 1810-1856
Description
Day-to-day decision makers on agricultural operations play a key role in maintaining both a sustainable and food secure agricultural society. This population, also defined as Principal Producers by the 2017 USDA Agricultural Census Report, has witnessed a significant decline in recent years, raising many questions surrounding why farmers are retiring faster than they can be replaced. To look closely at this phenomenon, this study focuses on the State of Ohio to hear first-hand from producers what they need to be successful through a series of semi-structured interviews. This study also maps recent changes in variables that define this issue from 2007-2017 using QGIS and USDA Agricultural Census data. The findings from this study show the recent decline of mid-sized agricultural operations and provide evidence linking declining rates of principal producer populations with specific features consistent with industrial agriculture. These findings are specific to the State of Ohio, but also raise much larger questions about which populations are experiencing more rapid rates of farm exit, and what implications these trends have for food security on a broader scale.
ContributorsMoore, Phillip (Author) / Chhetri, Nalini (Contributor) / Leonard, Bryan (Contributor) / Shrestha, Milan (Contributor)
Created2020
Description
An investigation is undertaken of a prototype building-integrated solar photovoltaic-powered thermal storage system and air conditioning unit. The study verifies previous thermodynamic and economic conclusions and provides a more thorough analysis. A parameterized model was created for optimization of the system under various conditions. The model was used to evaluate energy and cost savings to determine viability of the system in several circumstances, such as a residence in Phoenix with typical cooling demand. The proposed design involves a modified chest freezer as a thermal storage tank with coils acting as the evaporator for the refrigeration cycle. Surrounding the coils, the tank contains small containers of water for high-density energy storage submerged in a low freezing-point solution of propylene glycol. The cooling power of excess photovoltaic and off-peak grid power that is generated by the air conditioning compressor is stored in the thermal storage tank by freezing the pure water. It is extracted by pumping the glycol across the ice containers and into an air handler to cool the building. Featured results of the modeling include the determination of an optimized system for a super-peak rate plan, grid-connected Phoenix house that has a 4-ton cooling load and requires a corresponding new air conditioner at 4.5 kW of power draw. Optimized for the highest payback over a ten year period, the system should consist of a thermal storage tank containing 454 liters (120 gallons) of water, a 3-ton rated air conditioning unit, requiring 2.7 kW, which is smaller than conventionally needed, and no solar photovoltaic array. The monthly summer savings would be $45.The upfront cost would be $5489, compared to a conventional system upfront cost of $5400, for a payback period of 0.33 years. Over ten years, this system will provide $2600 of savings. To optimize the system for the highest savings over a twenty year period, a thermal storage tank containing 272 liters (72 gallons) of water, a 40-m2 photovoltaic array with 15% efficiency, and a 3.5-ton, 3.1-kW rated air conditioning unit should be installed for an upfront cost of $19,900. This would provide monthly summer savings of $225 and 1062 kWh grid electricity, with a payback period of only 11 years and a total cost savings of $12,300 over twenty years. In comparison, a system with the same size photovoltaic array but without storage would result in a payback period of 16 years. Results are also determined for other cooling requirements and installation sizes, such that the viability of this type of system in different conditions can be discussed. The use of this model for determining the optimized system configuration given different constraints is also described.
ContributorsMagerman, Beth Francine (Author) / Phelan, Patrick (Thesis director) / Goodnick, Stephen (Committee member) / Chhetri, Nalini (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2013-05
Description
Small-scale fisheries are globally ubiquitous, employing more than 99% of the world’s fishers and providing over half of the world’s seafood. However, small-scale fisheries face many management challenges including declining catches, inadequate resources and infrastructure, and overcapacity. Baja California Sur, Mexico (BCS) is a region with diverse small-scale fisheries; these fisheries are intense, poorly regulated, and overlap with foraging hot spots of endangered sea turtles. In partnership with researchers, fishers, managers, and practitioners from Mexico and the United States, I documented bycatch rates of loggerhead turtles at BCS that represent the highest known megafauna bycatch rates worldwide. Concurrently, I conducted a literature review that determined gear modifications were generally more successful than other commonly used fisheries management strategies for mitigating bycatch of vulnerable megafauna including seabirds, marine mammals, and sea turtles. I then applied these results by partnering with researchers, local fishers, and Mexico’s federal fisheries science agency to develop and test two gear modifications (i.e. buoyless and illuminated nets) in operating net fisheries at BCS as potential solutions to reduce bycatch of endangered sea turtles, improve fisheries sustainability, and maintain fisher livelihoods. I found that buoyless nets significantly reduced mean turtle bycatch rates by 68% while maintaining target catch rates and composition. By contrast, illuminated nets did not significantly reduce turtle bycatch rates across day-night periods, although they reduced mean turtle bycatch rates by 50% at night. Illuminated nets, however, significantly reduced mean rates of total bycatch biomass by 34% across day-night periods while maintaining target fish catch and market value. I conclude with a policy analysis of the unilateral identification of Mexico by the U.S. State Department under section 610 of the Magnusson-Stevens Fishery Conservation and Management Act for failure to manage bycatch of loggerhead turtles at BCS. Taken together, the gear modifications developed and tested here represent promising bycatch mitigation solutions with strong potential for commercial adoption, but fleet-wide conversion to more selective and turtle-friendly gear (e.g. hook and line and/or traps) at BCS, coupled with coordinated international conservation action, is ultimately needed to eliminate sea turtle bycatch and further improve fisheries sustainability.
ContributorsSenko, Jesse (Author) / Smith, Andrew (Thesis advisor) / Boggess, May (Committee member) / Chhetri, Nalini (Committee member) / Jenkins, Lekelia (Committee member) / Minteer, Ben (Committee member) / Arizona State University (Publisher)
Created2015
Description
Without scientific expertise, society may make catastrophically poor choices when faced with problems such as climate change. However, scientists who engage society with normative questions face tension between advocacy and the social norms of science that call for objectivity and neutrality. Policy established in 2011 by the Intergovernmental Panel on Climate Change (IPCC) required their communication to be objective and neutral and this research comprised a qualitative analysis of IPCC reports to consider how much of their communication is strictly factual (Objective), and value-free (Neutral), and to consider how their communication had changed from 1990 to 2013. Further research comprised a qualitative analysis of structured interviews with scientists and non-scientists who were professionally engaged in climate science communication, to consider practitioner views on advocacy. The literature and the structured interviews revealed a conflicting range of definitions for advocacy versus objectivity and neutrality. The practitioners that were interviewed struggled to separate objective and neutral science from attempts to persuade, and the IPCC reports contained a substantial amount of communication that was not strictly factual and value-free. This research found that science communication often blurred the distinction between facts and values, imbuing the subjective with the authority and credibility of science, and thereby damaging the foundation for scientific credibility. This research proposes a strict definition for factual and value-free as a means to separate science from advocacy, to better protect the credibility of science, and better prepare scientists to negotiate contentious science-based policy issues. The normative dimension of sustainability will likely entangle scientists in advocacy or the appearance of it, and this research may be generalizable to sustainability.
ContributorsMcClintock, Scott (Author) / Van Der Leeuw, Sander (Thesis advisor) / Klinsky, Sonja (Committee member) / Chhetri, Nalini (Committee member) / Hannah, Mark (Committee member) / Arizona State University (Publisher)
Created2015
Description
During the months from June to November 2012, the city of Bangalore was faced with a serious solid waste management (SWM) crisis. In the wake of the upheaval, the state court declared source segregation to be mandatory. Yet, while the legislation was clear, the pathway towards a course of action for the transition was not clear and hence, Bangalore was stuck in a state of limbo. The objectives for this thesis spiraled organically from this crisis. The first objective was to examine the gaps in Bangalore's transition to a more sustainable SWM system. Six particular gaps were identified, which in essence, were opportunities to re-shape the system. The gaps identified included: conflicting political agendas, the exclusion of some key actors, and lack of adequate attention to cultural aspects, provision of appropriate incentives, protection of livelihoods and promotion of innovation. Opportunities were found in better incentivization of sustainable SWM goals, protecting livelihoods that depend on waste, enhancing innovation and endorsing local, context based SWM solutions. Building on this understanding of gaps, the second objective was to explore an innovative, local, bottom-up waste-management model called the Vellore Zero Waste Model, and assess its applicability to Bangalore. The adaptability of the model depended on several factors such as, willingness of actors to redefine their roles and change functions, ability of the municipality to assure quality and oversight, willingness of citizen to source segregate, and most importantly, the political will and collective action needed to ensure and sustain the transition. The role of communication as a vital component to facilitate productive stakeholder engagement and to promote role change was evident. Therefore, the third objective of the study was to explore how interpersonal competencies and communication strategies could be used as a tool to facilitate stakeholder engagement and encourage collective action. In addressing these objectives, India was compared with Austria because Austria is often cited as having some of the best SWM practices in the world and has high recycling rates to show for its reputation.
ContributorsRengarajan, Nivedita (Author) / Aggarwal, Rimjhim (Thesis advisor) / Chhetri, Nalini (Committee member) / Manuel-Navarrete, David (Committee member) / Arizona State University (Publisher)
Created2013
Descriptionnone
ContributorsZamil, Ruaa (Author) / Parmentier, Mary J (Thesis advisor) / Chhetri, Nalini (Committee member) / Grossman, Gary (Committee member) / Arizona State University (Publisher)
Created2013
Description
Haiti has witnessed high deforestation rates in recent decades, caused largely by the fuel needs of a growing population. The resulting soil loss is estimated to have contributed towards a decline in agricultural productivity of 0.5% -1.2% per year since 1997. Recent studies show the potential of biochar use through pyrolysis technology to increase crop yields and improve soil health. However, the appropriateness of this technology in the context of Haiti remains unexplored. The three objectives of this research were to identify agricultural- and fuel-use-related needs and gaps in rural Haitian communities; determine the appropriateness of biochar pyrolyzer technology, used to convert agricultural biomass into a carbon-rich charcoal; and develop an action-oriented plan for use by development organizations, communities, and governmental institutions to increase the likelihood of adoption. Data were collected using participatory rural appraisal techniques involving 30 individual interviews and three focus-group discussions in the villages of Cinquantin and La Boule in the La Coupe region of central Haiti. Topics discussed include agricultural practices and assets, fuel use and needs, technology use and adoption, and social management practices. The Sustainable Livelihoods framework was used to examine the assets of households and the livelihood strategies being employed. Individual and focus group interviews were analyzed to identify specific needs and gaps. E.M. Rogers' Diffusion of Innovations theory was used to develop potential strategies for the introduction of pyrolysis technology. Preliminary results indicate biochar pyrolysis has potential to address agricultural and fuel needs in rural Haiti. Probable early adopters of biochar technology include households that have adopted new agricultural techniques in the past, and those with livestock. Education about biochar, and a variety of pyrolysis technology options from which villagers may select, are important factors in successful adoption of biochar use. A grain mill as an example in one of the study villages provides a model of ownership and use of pyrolysis technology that may increase its likelihood of successful adoption. Additionally, women represent a group that may be well suited to control a new local biochar enterprise, potentially benefiting the community.
ContributorsDelaney, Michael Ryan (Author) / Aggarwal, Rimjhim (Thesis advisor) / Chhetri, Nalini (Committee member) / Henderson, Mark (Committee member) / Arizona State University (Publisher)
Created2011
Description
A niche group of non-traditional sports have grown in popularity over the course of most of the last century but especially in the last few decades. Adventure sports provide alternative forms of physical activity typically involving elements of nature, speed, adrenaline, and physical risk. These sports often take place in remote locations, require specialized equipment, and receive limited exposure to those that are not participants. There are many factors that contribute to limited participation within adventure sports but their popularity has continued to grow. Participants frequently devote much of their time, effort, and money showing a true passion for their sport. A case study on water skiers was performed to learn more about adventure sports and their participants. A detailed description of competitive water skiing is included because the competition format is not widely known. It was found that there are a number of reasons why people competitively water ski. The main ones are the unique sensations it offers, the water ski community, and the environment in which it takes place. It is a tough sport to become involved because of the costs, time commitments, access to lakes, and lack of knowledgeable skiers willing to mentor beginners. Although for different reasons, all respondents seemed to truly love the sport. People participate in adventure sports because of the unique aspects and opportunities involved with sports of this nature. The second portion is a coaching guide on all three events, driving, and judging including video examples of all but very high difficulty tricks. These tips and advice have been derived from fifteen years of experience with competitive water skiing. There is no single way to water ski but this is what one skier has found to help at each stage of improvement. It could not have been accomplished without the unimaginable amount of support received from family, coaches, and friends. It is always better to be watched by a coach but that is not always possible. This guide will give skiers a starting point for what to think about to help them figure out how to continue to improve in all three events. With the necessary time, resources, ambition, and circumstances; a small group of people who know nothing about water skiing could learn to become high performance competitors. It will be left with Sun Devil Water Ski Club to help future skiers who do not always have another skier to help teach them.
ContributorsMechler, Mason Charles (Author) / Chhetri, Nalini (Thesis director) / Yesenski, Tara (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
ContributorsYang, Elliot (Performer) / Witt, Juliana (Performer) / ASU Library. Music Library (Publisher)
Created2017-12-01
ContributorsChen, Yen Wei (Contributor) / ASU Library. Music Library (Publisher)
Created2019-02-24