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- Creators: Arizona State University
Description
Phosphorus (P), an essential element for life, is becoming increasingly scarce, and its global management presents a serious challenge. As urban environments dominate the landscape, we need to elucidate how P cycles in urban ecosystems to better understand how cities contribute to — and provide opportunities to solve — problems of P management. The goal of my research was to increase our understanding of urban P cycling in the context of urban resource management through analysis of existing ecological and socio-economic data supplemented with expert interviews in order to facilitate a transition to sustainable P management. Study objectives were to: I) Quantify and map P stocks and flows in the Phoenix metropolitan area and analyze the drivers of spatial distribution and dynamics of P flows; II) examine changes in P-flow dynamics at the urban agricultural interface (UAI), and the drivers of those changes, between 1978 and 2008; III) compare the UAI's average annual P budget to the global agricultural P budget; and IV) explore opportunities for more sustainable P management in Phoenix. Results showed that Phoenix is a sink for P, and that agriculture played a primary role in the dynamics of P cycling. Internal P dynamics at the UAI shifted over the 30-year study period, with alfalfa replacing cotton as the main locus of agricultural P cycling. Results also suggest that the extent of P recycling in Phoenix is proportionally larger than comparable estimates available at the global scale due to the biophysical characteristics of the region and the proximity of various land uses. Uncertainty remains about the effectiveness of current recycling strategies and about best management strategies for the future because we do not have sufficient data to use as basis for evaluation and decision-making. By working in collaboration with practitioners, researchers can overcome some of these data limitations to develop a deeper understanding of the complexities of P dynamics and the range of options available to sustainably manage P. There is also a need to better connect P management with that of other resources, notably water and other nutrients, in order to sustainably manage cities.
ContributorsMetson, Genevieve (Author) / Childers, Daniel (Thesis advisor) / Aggarwal, Rimjhim (Thesis advisor) / Redman, Charles (Committee member) / Arizona State University (Publisher)
Created2011
Description
The global demand and trade for fruits and vegetables is increasing at national and international levels. The fresh fruits and vegetables supply chain are highly vulnerable to contamination and can be easily spoiled due to their perishable nature. Due to increases in fresh fruit and vegetable trade shipment volume between countries, the fresh food supply chain area is the highly susceptible and frequently prone to food contamination. The inability of firms in the fresh food business to have a good supply chain visibility and tracking system is one of the prominent reasons for food safety failure. Therefore, in order to avoid food safety risk and to supply safe food to consumers, the firms need to have an efficient traceability system in their supply chain. Most of the research in the food supply chain area suggests the implementation of a highly efficient tracking system called RFID (Radio frequency identification) technology to firms in the food industry. The medium scale firms in the fresh food supply chain business are skeptical about implementing the RFID technology equipped traceability system due to its high cost of investment and low margins on fresh food sales. This research developed two methods to measure the probability of food safety risk in food supply chain. These methods use the information gain from RFID traceability systems as a tool to measure the amount of risk in the fresh food supply chain. The stochastic optimization model is applied in this study to determine the risk premium by investing in RFID technology over the electronic barcode traceability system. The results show that there is a reduction in buyer (Type II error) and seller risk (Type I error) for RFID technology employed traceability system compared to electronic barcode system. It is found from stochastic optimization results that there is a positive risk premium by investing in RFID traceability system over the current systems and suggests the implementation of RFID traceability system for complex medium scale fresh produce imports to reduce the food safety risks. This research encourages the food industries and government agencies to evaluate alternatives to update supply chain system with RFID technology.
ContributorsJanke, Deepak Kumar (Author) / Nganje, William (Thesis advisor) / Schmitz, Troy (Committee member) / Thor, Eric (Committee member) / Arizona State University (Publisher)
Created2011
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
This dissertation investigates the long-term consequences of human land-use practices in general, and in early agricultural villages in specific. This pioneering case study investigates the "collapse" of the Early (Pre-Pottery) Neolithic lifeway, which was a major transformational event marked by significant changes in settlement patterns, material culture, and social markers. To move beyond traditional narratives of cultural collapse, I employ a Complex Adaptive Systems approach to this research, and combine agent-based computer simulations of Neolithic land-use with dynamic and spatially-explicit GIS-based environmental models to conduct experiments into long-term trajectories of different potential Neolithic socio-environmental systems. My analysis outlines how the Early Neolithic "collapse" was likely instigated by a non-linear sequence of events, and that it would have been impossible for Neolithic peoples to recognize the long-term outcome of their actions. The experiment-based simulation approach shows that, starting from the same initial conditions, complex combinations of feedback amplification, stochasticity, responses to internal and external stimuli, and the accumulation of incremental changes to the socio-natural landscape, can lead to widely divergent outcomes over time. Thus, rather than being an inevitable consequence of specific Neolithic land-use choices, the "catastrophic" transformation at the end of the Early Neolithic was an emergent property of the Early Neolithic socio-natural system itself, and thus likely not an easily predictable event. In this way, my work uses the technique of simulation modeling to connect CAS theory with the archaeological and geoarchaeological record to help better understand the causes and consequences of socio-ecological transformation at a regional scale. The research is broadly applicable to other archaeological cases of resilience and collapse, and is truly interdisciplinary in that it draws on fields such as geomorphology, computer science, and agronomy in addition to archaeology.
ContributorsUllah, Isaac (Author) / Barton, C. Michael (Thesis advisor) / Banning, Edward B. (Committee member) / Clark, Geoffrey (Committee member) / Arrowsmith, J. Ramon (Committee member) / Arizona State University (Publisher)
Created2013
Description
The lack of food safety in a grower's produce presents the grower with two risks; (1) that an item will need to be recalled from the market, incurring substantial costs and damaging brand equity and (2) that the entire market for the commodity becomes impaired as consumers associate all produce as being risky to eat. Nowhere is this more prevalent than in the leafy green industry, where recalls are relatively frequent and there has been one massive E. coli outbreak that rocked the industry in 2006. The purpose of this thesis is to examine insurance policies that protect growers from these risks. In doing this, a discussion of current recall insurance policies is presented. Further, actuarially fair premiums for catastrophic revenue insurance policies are priced through a contingent claims framework. The results suggest that spinach industry revenue can be insured for $0.02 per carton. Given the current costs of leafy green industry food safety initiatives, growers may be willing to pay for such an insurance policy.
ContributorsPagaran, Jeremy (Author) / Manfredo, Mark R. (Thesis advisor) / Richards, Timothy J. (Thesis advisor) / Nganje, William (Committee member) / Arizona State University (Publisher)
Created2013
Description
Irrigation agriculture has been heralded as the solution to feeding the world's growing population. To this end, irrigation agriculture is both extensifying and intensifying in arid regions across the world in an effort to create highly productive agricultural systems. Over one third of modern irrigated fields, however, show signs of serious soil degradation, including salinization and waterlogging, which threaten the productivity of these fields and the world's food supply. Surprisingly, little ecological data on agricultural soils have been collected to understand and address these problems. How, then, can expanding and intensifying modern irrigation systems remain agriculturally productive for the long-term? Archaeological case studies can provide critical insight into how irrigated agricultural systems may be sustainable for hundreds, if not thousands, of years. Irrigation systems in Mesopotamia, for example, have been cited consistently as a cautionary tale of the relationship between mismanaged irrigation systems and the collapse of civilizations, but little data expressly link how and why irrigation failed in the past. This dissertation presents much needed ecological data from two different regions of the world - the Phoenix Basin in southern Arizona and the Pampa de Chaparrí on the north coast of Peru - to explore how agricultural soils were affected by long-term irrigation in a variety of social and economic contexts, including the longevity and intensification of irrigation agriculture. Data from soils in prehispanic and historic agricultural fields indicate that despite long-lived and intensive irrigation farming, farmers in both regions created strategies to sustain large populations with irrigation agriculture for hundreds of years. In the Phoenix Basin, Hohokam and O'odham farmers relied on sedimentation from irrigation water to add necessary fine sediments and nutrients to otherwise poor desert soils. Similarly, on the Pampa, farmers relied on sedimentation in localized contexts, but also constructed fields with ridges and furrows to draw detrimental salts away from planting surfaces in the furrows on onto the ridges. These case studies are then compared to failing modern and ancient irrigated systems across the world to understand how the centralization of management may affect the long-term sustainability of irrigation agriculture.
ContributorsStrawhacker, Colleen (Author) / Spielmann, Katherine A. (Thesis advisor) / Hall, Sharon J (Committee member) / Nelson, Margaret C. (Committee member) / Sandor, Jonathan A (Committee member) / Arizona State University (Publisher)
Created2013
Description
"Navigation, Trade, and Consumption in Seventeenth Century Oxfordshire" investigates how the inhabitants of Oxfordshire transitioned from an agricultural to a consumer community during the Jacobean and post-Restoration eras. In agrarian England, this reconfigured landscape was most clearly embodied in the struggle over the access to available land. Focusing on the gentleman farmer's understanding of the fiscal benefits of enclosure and land acquisition, I argue that the growth in agricultural markets within Oxfordshire led to a growing prosperity, which was most clearly articulated in the community's rise as viable luxury goods consumers. By juxtaposing probate documents, inventories, pamphlets, and diaries from the market towns of Burford, Chipping Norton, and Henley-on-Thames in Oxfordshire, this study examines the process by which these late sixteenth and early seventeenth century agricultural communities began to embrace the consumption of luxury goods, and, most importantly, purely market-based understanding of agrarian life.
ContributorsO'Connell, Joseph (Author) / Warnicke, Retha (Thesis advisor) / Arizona State University (Publisher)
Created2013
Description
In the past 100 years pet, zoo/aquarium, and research animals have gained unprecedented legal protection from unnecessary human harm via the creation of strict animal cruelty laws. Due to the work of moral philosophers and compassionate lawyers/judges animal cruelty laws have been improved to provide harsher punishments for violations, had their scopes widened to include more animals and had their language changed to better match our evolving conception of animals as independent living entities rather than as merely things for human use. However, while the group of pet, zoo/aquarium, and research animals has enjoyed more consideration by the US legal system, another group of animals has inexplicably been ignored. The farm animals that humans raise for use as food are exempted from nearly every state and federal animal cruelty law for no justifiable reason. In this paper I will argue that our best moral and legal theories concede that we should take animal suffering seriously, and that no relevant difference exists between the group of animals protected by animal cruelty laws and farm animals. Given the lack of a relevant distinction between these two groups I will conclude that current animal cruelty laws should be amended to include farm animals.
ContributorsDeCoster, Miles (Author) / McGregor, Joan (Thesis advisor) / Blackson, Thomas (Committee member) / Calhoun, Cheshire (Committee member) / Arizona State University (Publisher)
Created2012
Description
The Phoenix area had no sizable Mexican presence before the U.S. took over the territory. Some assumed that the region was founded completely by whites from the outset. Whites and Mexicans actually held nearly equal populations throughout the first two decades of settlement. Though they did not hold equal status, their cohabitation was largely characterized by mutual interdependence and respect. Transforming the Salt River Valley's desert terrain into a regional agricultural hub depended on the Sonorans' preindustrial skills. As the town modernized, a new class of resident sought large scale projects to integrate Phoenix into the U.S. economy. Two pivotal projects achieved this. First, railroad spur lines made Phoenix accessible for migrants, as well as allowing farmers to supply commercial markets profitably. Second, the massive Roosevelt Dam secured a stable water supply for valley farmers. While these projects provided the foundation for development, it was cotton that brought commercial success. Throughout World War I, valley cotton growers capitalized on the booming cotton market by expanding their average acreage from 400 acres in 1912 to 130,000 acres in 1920. This rapid escalation to meet wartime demands depended upon a massive seasonal labor force from Mexico. While this boom brought prosperity to valley farmers, it solidified the Mexican's role in the Salt River Valley as little more than a laborer. Valley cotton growers impressively managed all labor issues through a well-organized collective association. Over-recruitment and wage setting kept workers from collective bargaining for better wages. The cotton growers' hegemony crashed along with cotton prices in 1921. Though the industry recovered fairly quickly, the cotton growers faced a new challenge in the rising national clamor to restrict Mexican immigration to the U.S. Though growers fought restrictions in Congressional hearings throughout the decade, the economic crash of 1929 finally ended widespread Mexican immigration. By the time of the crash, most Mexicans who remained lived in the agricultural peripheries or scattered urban barrios.
ContributorsWalker, Scott (Author) / Rosales, Francisco A (Thesis advisor) / Vandermeer, Phil (Committee member) / Stoner, Lynn (Committee member) / Arizona State University (Publisher)
Created2012
Description
Understanding agricultural land use requires the integration of natural factors, such as climate and nutrients, as well as human factors, such as agricultural intensification. Employing an agroecological framework, I use the Perry Mesa landscape, located in central Arizona, as a case study to explore the intersection of these factors to investigate prehistoric agriculture from A.D. 1275-1450. Ancient Perry Mesa farmers used a runoff agricultural strategy and constructed extensive alignments, or terraces, on gentle hillslopes to slow and capture nutrient rich surface runoff generated from intense rainfall. I investigate how the construction of agricultural terraces altered key parameters (water and nutrients) necessary for successful agriculture in this arid region. Building upon past work focused on agricultural terraces in general, I gathered empirical data pertaining to nutrient renewal and water retention from one ancient runoff field. I developed a long-term model of maize growth and soil nutrient dynamics parameterized using nutrient analyses of runoff collected from the sample prehistoric field. This model resulted in an estimate of ideal field use and fallow periods for maintaining long-term soil fertility under different climatic regimes. The results of the model were integrated with estimates of prehistoric population distribution and geographical characterizations of the arable lands to evaluate the places and periods when sufficient arable land was available for the type of cropping and fallowing systems suggested by the model (given the known climatic trends and land use requirements). Results indicate that not only do dry climatic periods put stress on crops due to reduced precipitation but that a reduction in expected runoff events results in a reduction in the amount of nutrient renewal due to fewer runoff events. This reduction lengthens estimated fallow cycles, and probably would have increased the amount of land necessary to maintain sustainable agricultural production. While the overall Perry Mesa area was not limited in terms of arable land, this analysis demonstrates the likely presence of arable land pressures in the immediate vicinity of some communities. Anthropological understandings of agricultural land use combined with ecological tools for investigating nutrient dynamics provides a comprehensive understanding of ancient land use in arid regions.
ContributorsKruse-Peeples, Melissa R (Author) / Spielmann, Katherine A. (Thesis advisor) / Abbott, David R. (Committee member) / Hall, Sharon J. (Committee member) / Kintigh, Keith W. (Committee member) / Arizona State University (Publisher)
Created2013