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- All Subjects: Agriculture
- All Subjects: Ecology
- Creators: School of Sustainability
Is there a mismatch between urban farmers’ perceptions of their farm’s environmental sustainability and its actual environmental impact? Focusing on the use of water and nutrients on each farm as described by the farmers through interviews, it is evident that there is some level of disconnect between ideals and practices. This project may aid in bridging the gap between the two in regard to the farmers’ sustainability goals. This project will move forward by continuing interviews with farmers as well as collecting soil and water from the farms in order to more accurately quantify the sustainability of the farms’ practices. This project demonstrates that there is some degree of misalignment between perception and reality. Two farms claimed they were sustainable when their practices did not reflect that, while 2 farms said they were not sure if they were sustainable when their practices indicated otherwise. Samples from two farms showed high concentrations of nutrients and salts, supporting the idea that there may be a mismatch between perceived and actual sustainability.
Plasticizers are plastic additives used to enhance the physical properties of plastic and are ubiquitous in the environment. A class of plasticizer compounds called phthalate esters that are not fully eliminated in wastewater treatment facilities are relevant to the ecological health of downstream ecosystems and urban areas due to their ecotoxicity, tendency for soil accumulation, and the emerging concern about their effects on public health. However, plasticizer concentrations in a constructed wetland environment have rarely been studied in the United States, prompting the need for a method of plasticizer quantification in the Tres Rios Constructed Wetlands which are sustained by the effluent of the 91st Avenue Wastewater Treatment Plant in Phoenix, Arizona. The concentrations of four common plasticizer compounds (dimethyl: DMP, diethyl: DEP, di-n-butyl: DnBP, and bis(2-ethylhexyl): DEHP phthalate) at five sites across the wetland surface water were quantified using solid-phase extraction followed by gas chromatography coupled with mass spectrometry (GC/MS). The sampling period included four sample sets taken from March 2022 to September 2022, which gave temporal data in addition to spatial concentration data. Quantification and quality control were performed using internal standard calibration, replicate samples, and laboratory blanks. Higher molecular weight phthalates accumulated in the wetland surface water at significantly higher average concentrations than those of lower molecular weight at a 95% confidence level, ranging from 8 ng/L to 7349 ng/L and 4 ng/L to 27876 ng/L for DnBP and DEHP, respectively. Concentrations for dimethyl phthalate and diethyl phthalate were typically less than 50 ng/L and were often below the method detection limit. Average concentrations of DnBP and DEHP were significantly higher during periods of high temperatures and arid conditions. The spatial distribution of phthalates was analyzed. Most importantly, a method for successful ultra-trace quantification of plasticizers at Tres Rios was established. These results confirm the presence of plasticizers at Tres Rios and a significant seasonal increase in their surface water concentrations. The developed analytical procedure provides a solid foundation for the Wetlands Environmental Ecology Lab at ASU to further investigate plasticizers and contaminants of emerging concern and determine their ultimate fate through volatilization, sorption, photodegradation, hydrolysis, microbial biodegradation, and phytoremediation studies.
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.
Animal agriculture is a growing industry worldwide as the global demand for animal products increases. This has resulted in many harmful unintended consequences for human health, the environment, and animal welfare. This paper aims to uncover the hidden costs of negative externalities by answering the question: What types of subsidies is the US government distributing to the animal agriculture industry and in what amount? This paper will begin with some background on a few of the externalities created by the animal agriculture industry focusing specifically on environmental issues of water, air, and deforestation. Once this background is established, this will show that animal agriculture is in fact a negative-externality-generating industry. Next, subsidies will be defined and the principal findings of the research will reveal the different forms of support that the US government provides to animal agriculture. Lastly, these subsidies, both direct and indirect, will be quantified.