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Description
Many manmade chemicals used in consumer products are ultimately washed down the drain and are collected in municipal sewers. Efficient chemical monitoring at wastewater treatment (WWT) plants thus may provide up-to-date information on chemical usage rates for epidemiological assessments. The objective of the present study was to extrapolate this concept,

Many manmade chemicals used in consumer products are ultimately washed down the drain and are collected in municipal sewers. Efficient chemical monitoring at wastewater treatment (WWT) plants thus may provide up-to-date information on chemical usage rates for epidemiological assessments. The objective of the present study was to extrapolate this concept, termed 'sewage epidemiology', to include municipal sewage sludge (MSS) in identifying and prioritizing contaminants of emerging concern (CECs). To test this the following specific aims were defined: i) to screen and identify CECs in nationally representative samples of MSS and to provide nationwide inventories of CECs in U.S. MSS; ii) to investigate the fate and persistence in MSS-amended soils, of sludge-borne hydrophobic CECs; and iii) to develop an analytical tool relying on contaminant levels in MSS as an indicator for identifying and prioritizing hydrophobic CECs. Chemicals that are primarily discharged to the sewage systems (alkylphenol surfactants) and widespread persistent organohalogen pollutants (perfluorochemicals and brominated flame retardants) were analyzed in nationally representative MSS samples. A meta-analysis showed that CECs contribute about 0.04-0.15% to the total dry mass of MSS, a mass equivalent of 2,700-7,900 metric tonnes of chemicals annually. An analysis of archived mesocoms from a sludge weathering study showed that 64 CECs persisted in MSS/soil mixtures over the course of the experiment, with half-lives ranging between 224 and >990 days; these results suggest an inherent persistence of CECs that accumulate in MSS. A comparison of the spectrum of chemicals (n=52) analyzed in nationally representative biological specimens from humans and MSS revealed 70% overlap. This observed co-occurrence of contaminants in both matrices suggests that MSS may serve as an indicator for ongoing human exposures and body burdens of pollutants in humans. In conclusion, I posit that this novel approach in sewage epidemiology may serve to pre-screen and prioritize the several thousands of known or suspected CECs to identify those that are most prone to pose a risk to human health and the environment.
ContributorsVenkatesan, Arjunkrishna (Author) / Halden, Rolf U. (Thesis advisor) / Westerhoff, Paul (Committee member) / Fox, Peter (Committee member) / Arizona State University (Publisher)
Created2013
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Description
The consumption of feedstocks from agriculture and forestry by current biofuel production has raised concerns about food security and land availability. In the meantime, intensive human activities have created a large amount of marginal lands that require management. This study investigated the viability of aligning land management with biofuel production

The consumption of feedstocks from agriculture and forestry by current biofuel production has raised concerns about food security and land availability. In the meantime, intensive human activities have created a large amount of marginal lands that require management. This study investigated the viability of aligning land management with biofuel production on marginal lands. Biofuel crop production on two types of marginal lands, namely urban vacant lots and abandoned mine lands (AMLs), were assessed. The investigation of biofuel production on urban marginal land was carried out in Pittsburgh between 2008 and 2011, using the sunflower gardens developed by a Pittsburgh non-profit as an example. Results showed that the crops from urban marginal lands were safe for biofuel. The crop yield was 20% of that on agricultural land while the low input agriculture was used in crop cultivation. The energy balance analysis demonstrated that the sunflower gardens could produce a net energy return even at the current low yield. Biofuel production on AML was assessed from experiments conducted in a greenhouse for sunflower, soybean, corn, canola and camelina. The research successfully created an industrial symbiosis by using bauxite as soil amendment to enable plant growth on very acidic mine refuse. Phytoremediation and soil amendments were found to be able to effectively reduce contamination in the AML and its runoff. Results from this research supported that biofuel production on marginal lands could be a unique and feasible option for cultivating biofuel feedstocks.
ContributorsZhao, Xi (Author) / Landis, Amy (Thesis advisor) / Fox, Peter (Committee member) / Chester, Mikhail (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Ecolabels are the main driving force of consumer knowledge in the realm of sustainable product purchasing. While ecolabels strive to improve consumer's purchasing decisions, they have overwhelmed the market, leaving consumers confused and distrustful of what each label means. This study attempts to validate and understand environmental concerns commonly found

Ecolabels are the main driving force of consumer knowledge in the realm of sustainable product purchasing. While ecolabels strive to improve consumer's purchasing decisions, they have overwhelmed the market, leaving consumers confused and distrustful of what each label means. This study attempts to validate and understand environmental concerns commonly found in ecolabel criteria and the implications they have within the life cycle of a product. A life cycle assessment (LCA) case study of cosmetic products is used in comparison with current ecolabel program criteria to assess whether or not ecolabels are effectively driving environmental improvements in high impact areas throughout the life cycle of a product. Focus is placed on determining the general issues addressed by ecolabelling criteria and how these issues relate to hotspots derived through a practiced scientific methodology. Through this analysis, it was determined that a majority the top performing supply chain environmental impacts are covered, in some fashion, within ecolabelling criteria, but some, such as agricultural land occupation, are covered to a lesser extent or not at all. Additional criteria are suggested to fill the gaps found in ecolabelling programs and better address the environmental impacts most pertinent to the supply chain. Ecolabels have also been found to have a broader coverage then what can currently be addressed using LCA. The results of this analysis have led to a set of recommendations for furthering the integration between ecolabels and life cycle tools.
ContributorsBernardo, Melissa (Author) / Dooley, Kevin (Thesis advisor) / Chester, Mikhail (Thesis advisor) / Fox, Peter (Committee member) / Arizona State University (Publisher)
Created2012
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Description
C.C. Cragin Reservoir’s location in the Coconino National Forest, Arizona makes it prone to wild fire. This study focused on the potential impacts of such a wild fire on the reservoir’s annual thermal stratification cycle impacts and water quality. The annual thermal stratification cycle impacted the reservoir’s water

C.C. Cragin Reservoir’s location in the Coconino National Forest, Arizona makes it prone to wild fire. This study focused on the potential impacts of such a wild fire on the reservoir’s annual thermal stratification cycle impacts and water quality. The annual thermal stratification cycle impacted the reservoir’s water quality by increasing hypolimnion concentrations of magnesium, iron, turbidity, and specific ultraviolet absorbance (SUVA) values, as well as resulting in the hypolimnion having decreased dissolved oxygen concentrations during stratified months. The scarification process did not affect the dissolved organic carbon (DOC) concentrations in the reservoir or the total/dissolved nitrogen and phosphorous concentrations. Some general water quality trends that emerged were that phosphorous was the limiting nutrient, secchi disk depth and chlorophyll a concentration are inversely related, and no metals were found to be in concentrations that would violate an EPA drinking water maximum contaminant level (MCL). A carbon mass model was developed and parameterized using DOC measurements, and then using historic reservoir storage and weather data, the model simulated DOC concentrations in the reservoir following four hypothetical wild fire events. The model simulated varying initial reservoir storage volumes, initial flush volumes, and flush DOC concentrations, resulting in reservoir DOC concentrations varying from 17.41 mg/L to 8.82 mg/L.
ContributorsFlatebo, Theodore (Author) / Westerhoff, Paul K (Thesis advisor) / Fox, Peter (Committee member) / Perreault, Francois (Committee member) / Arizona State University (Publisher)
Created2018
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Description
Quagga Mussels (Dreissena bugensis) are an invasive species of mollusk that have established themselves within the Colorado River system of Arizona since 2007. However, despite close proximity and frequent travel by recreational boaters between reservoirs, they have not yet infested the Salt River or Verde River systems. Laboratory experimentation was

Quagga Mussels (Dreissena bugensis) are an invasive species of mollusk that have established themselves within the Colorado River system of Arizona since 2007. However, despite close proximity and frequent travel by recreational boaters between reservoirs, they have not yet infested the Salt River or Verde River systems. Laboratory experimentation was done to test the survival rate of adult D. bugensis specimens in waters collected from Bartlett Lake (Verde River), Saguaro Lake (Salt River), and Salt River Project (SRP) canals (Salt River/Verde River/Colorado River blend) as well as Central Arizona Project (CAP) canals with the addition of turbidity to simulate high runoff storm events. Under each condition, adult survival for a time period of 21 days exceeded 98%, ruling out water chemistry or turbidity as a factor. Spawning was investigated using mussels collected from Lake Pleasant in August 2015. In 4 trials of serotonin dosage between 0.5 – 1.0 mMol, spawning was not successful. Calanoid copepod predation was also investigated by field sampling at Lake Pleasant, Saguaro Lake, and Bartlett Lake during September 2015. Calanoid copepods were identified in Lake Pleasant at a density of 104.22 individuals per cubic meter at a depth of 2 meters and 9.75 individuals per cubic meter at the surface. Calanoid copepods were not found in Bartlett Lake or Saguaro Lake, ruling out copepod predation as a factor. Finally, dissolved oxygen and temperature trends were analyzed in each reservoir. While temperature profiles are similar throughout the year, seasonal drops in dissolved oxygen below survivable concentrations for D. bugensis has been observed in both Saguaro Lake and Bartlett Lake but not Lake Pleasant, representing the most plausible explanation for no observed infestation.
ContributorsSokolowski, Matthew (Author) / Fox, Peter (Thesis advisor) / Abbaszadegan, Morteza (Thesis advisor) / Alum, Absar (Committee member) / Arizona State University (Publisher)
Created2015
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Description
For more than 100 years, the Unite States National Park Service (NPS) has been guided by a mandate to preserve parks and their resources for the enjoyment of present and future generations. But all parks are subject to conditions that may frustrate preservation efforts. Climate change is melting the glaciers.

For more than 100 years, the Unite States National Park Service (NPS) has been guided by a mandate to preserve parks and their resources for the enjoyment of present and future generations. But all parks are subject to conditions that may frustrate preservation efforts. Climate change is melting the glaciers. Rising seas are sweeping away protected shorelines. Development projects, accompanied by air, water, light, and noise pollution, edge closer to parks and fragment habitats. The number of visitors and vested interests are swelling and diversifying. Resources for preservation, such as funds and staff, seem to be continuously shrinking, at least relative to demand.

Still, the NPS remains committed to the preservation of our natural and cultural heritage. Yet the practice of that promise is evolving, slowly and iteratively, but detectably. Through explorations of legal and scholarly literature, as well as interviews across the government, non-profit, and academic sectors, I’ve tracked the evolution of preservation in parks. How is preservation shifting to address socio-ecological change? How has preservation evolved before? How should the NPS preserve parks moving forward?

The practice of preservation has come to rely on science, including partnerships with academic researchers, as well as inventory and monitoring programs. That shift has in part been guided by goals that have also become more informed by science, like ecological integrity. While some interviewees see science as a solution to the NPS’s challenges, others wonder how applying science can get “gnarly,” due to uncertainty, lack of clear policies, and the diversity of parks and resources. “Gnarly” questions stem in part from the complexity of the NPS as a socio-ecological system, as well as from disputed, normative concepts that underpin the broader philosophy of preservation, including naturalness. What’s natural in the context of pervasive anthropogenic change? Further, I describe how parks hold deep, sometimes conflicting, cultural and symbolic significance for their local and historical communities and for our nation. Understanding and considering those values is part of the gnarly task park managers face in their mission to preserve parks. I explain why this type of conceptual and values-based uncertainty cannot be reduced through science.
ContributorsSullivan Govani, Michelle (Author) / Minteer, Ben A (Thesis advisor) / Budruk, Megha (Committee member) / Sarewitz, Daniel (Committee member) / Theuer, Jason (Committee member) / Arizona State University (Publisher)
Created2019
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Description
Trails perform an essential function in protected lands by routing visitors along planned, sustainable surfaces. However, when visitors deviate from official trails in sufficient numbers, it can lead to the creation of social trails. These visitor-created pathways are not sustainably designed and can severely degrade both the stability and appearance

Trails perform an essential function in protected lands by routing visitors along planned, sustainable surfaces. However, when visitors deviate from official trails in sufficient numbers, it can lead to the creation of social trails. These visitor-created pathways are not sustainably designed and can severely degrade both the stability and appearance of protected areas. A multitude of recreation motivations among visitors and a lack of resources among land management agencies have made the mitigation and closure of social trails a perennial concern. A sustainable, economical strategy that does not require the continual diversion of staff is needed to address social trails. In this study, two techniques that stand out in the research literature for their efficacy and practicality were tested on a social trail closure in South Mountain Park, a high-use, urban-proximate mountain park in Phoenix, AZ. A research design with additive treatments utilizing the site management technique known as trail mitigation, sometimes referred to as brushing in the literature, followed by theory-grounded signage incorporating injunctive-proscriptive wording, an attribution message, and a reasoning message targeting visitor behavioral beliefs, norms, and control was applied and assessed using unobtrusive observation. Both treatments reduced observed off-trail hiking from 75.4% to 0%, though traces of footsteps and attempts to re-open the trail revealed the existence of unobserved “entrenched” users. With entrenched users attempting to reopen the trail, trail mitigation represented an effective but vulnerable approach while the signage represented a long-lasting “hardened” approach that provides an educational message, management’s stance on the closure, and which might put social pressure on the entrenched user(s).
ContributorsRiske, Taylor (Author) / Budruk, Megha (Thesis advisor) / Andereck, Kathy (Committee member) / Avitia, Alonso (Committee member) / Arizona State University (Publisher)
Created2018