Matching Items (16)
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- All Subjects: Nitrogen
- Creators: School of Sustainability
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 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
Description
In this paper, I analyze representations of nature in popular film, using the feminist / deconstructionist concept of a dualism to structure my critique. Using Val Plumwood’s analysis of the logical structure of dualism and the 5 ‘features of a dualism’ that she identifies, I critique 5 popular movies – Star Wars, Lord of the Rings, Brave, Grizzly Man, and Planet Earth – by locating within each of them one of the 5 features and explaining how the movie functions to reinforce the Nature/Culture dualism . By showing how the Nature/Culture dualism shapes and is shaped by popular cinema, I show how “Nature” is a social construct, created as part of this very dualism, and reified through popular culture. I conclude with the introduction of a number of ‘subversive’ pieces of visual art that undermine and actively deconstruct the Nature/Culture dualism and show to the viewer a more honest presentation of the non-human world.
ContributorsBarton, Christopher Joseph (Author) / Broglio, Ron (Thesis director) / Minteer, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2015-05
Hiking and Hegemony: Destabilizing the nature/culture and gender binaries through outdoor recreation
Description
This paper explores the contested relationships between nature, culture, and gender. In order to analyze these relationships, we look specifically at outdoor recreation. Furthermore, we employ poststructuralist feminist theory in order to produce three frameworks; the first of which is titled Mother Nature’s Promiscuous Past. Rooted in Old World and colonial values, this framework illustrates the flawed feminization of nature by masculinity, and its subsequent extortion of anything related to femininity — including women and nature itself. This belief barred women from nature, resulting in a lack of access for women to outdoor recreation.
Our second framework, titled The Pleasurable Potential of Outdoor Recreation, cites second-wave feminism as a catalyst for women’s participation in wilderness exploration and outdoor recreation. The work of radical feminists and the women’s liberation movement in 1960s and 1970s empowered women at home, in the workplace, and eventually, in the outdoors; women reclaimed their wilderness, yet they continued to employ Framework One’s feminization of nature. Ecofeminsim brought together nature and women, seeking to bring justice to two groups wronged by the same entity: masculinity. In this context, outdoor recreation is empowering for women.
Despite the potential of Framework Two to reinscribe and better the experiences of women in outdoor recreation, we argue that both Frameworks One and Two perpetuate the gender binary and the nature/culture binary, because they are based upon the notion that women are in fact fundamentally different and separate from men, the notion that nature is an entity separate from culture, or human society, as well as the notion that nature is in fact a feminine entity.
Our third framework, Deer Pay No Mind to Your Genitals, engages poststructuralism, asserting that outdoor recreation and activities that occur in nature can serve to destabilize and deconstruct notions of the gender binary. However, we argue that care must be exercised during this process as not to perpetuate the problematic nature/culture binary, a phenomenon that is unproductive in terms of both sustainability and gender liberation. Outdoor recreation has been used by many as a tool to deconstruct numerous societal constraints, including the gender binary; this, however, continues to attribute escapist and isolationist qualities toward nature, and therefore perpetuating the nature/culture divide. Ultimately, we argue outdoor recreation can and should be used as a tool deconstruct the gender binary, however needs to account for the fact that if nature is helping to construct elements of culture, then the two cannot be separate.
Our second framework, titled The Pleasurable Potential of Outdoor Recreation, cites second-wave feminism as a catalyst for women’s participation in wilderness exploration and outdoor recreation. The work of radical feminists and the women’s liberation movement in 1960s and 1970s empowered women at home, in the workplace, and eventually, in the outdoors; women reclaimed their wilderness, yet they continued to employ Framework One’s feminization of nature. Ecofeminsim brought together nature and women, seeking to bring justice to two groups wronged by the same entity: masculinity. In this context, outdoor recreation is empowering for women.
Despite the potential of Framework Two to reinscribe and better the experiences of women in outdoor recreation, we argue that both Frameworks One and Two perpetuate the gender binary and the nature/culture binary, because they are based upon the notion that women are in fact fundamentally different and separate from men, the notion that nature is an entity separate from culture, or human society, as well as the notion that nature is in fact a feminine entity.
Our third framework, Deer Pay No Mind to Your Genitals, engages poststructuralism, asserting that outdoor recreation and activities that occur in nature can serve to destabilize and deconstruct notions of the gender binary. However, we argue that care must be exercised during this process as not to perpetuate the problematic nature/culture binary, a phenomenon that is unproductive in terms of both sustainability and gender liberation. Outdoor recreation has been used by many as a tool to deconstruct numerous societal constraints, including the gender binary; this, however, continues to attribute escapist and isolationist qualities toward nature, and therefore perpetuating the nature/culture divide. Ultimately, we argue outdoor recreation can and should be used as a tool deconstruct the gender binary, however needs to account for the fact that if nature is helping to construct elements of culture, then the two cannot be separate.
ContributorsPolick-Kirkpatrick, Kaelyn (Co-author) / Downing, Haley Marie (Co-author) / Dove-Viebahn, Aviva (Thesis director) / Schoon, Michael (Committee member) / School of Sustainability (Contributor) / School of Social Transformation (Contributor) / Economics Program in CLAS (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Backcountry Broadcasts is a multimedia project that aims to empower women in the great outdoors. This platform serves to inspire, encourage and appreciate women in the wilderness through photography, personal stories and more. Through our passion for the outdoors, we're incorporating our own female experience with the voices of others to bring light to the importance of gender inclusivity in the backcountry.
ContributorsPearce, Kyla Annika (Co-author) / Nardizzi, Ariella (Co-author) / Santos, Fernanda (Thesis director) / Babits, Sadie (Committee member) / Walter Cronkite School of Journalism and Mass Comm (Contributor) / The Sidney Poitier New American Film School (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
My thesis explores the development of a new treatment option for children with Amblyopia. I did a lot of research into existing treatment options as well as interviewing patients and their parents do figure out why these treatments were not working. I interviewed a pediatric ophthalmologist to better understand this condition from their point of view. I also did a competitive analysis to see who else was in this marketplace. From the insights I gathered I was able to create a user journey map to see where the most problems arose during the experience from Diagnoses to end of treatment. With this research I was able to design a new treatment plan that was focused on empathizing with the user. I developed several concepts ranging from lo-fi to blue sky. I tested these concepts by making models and getting feedback from the user. I developed the actual design of the glasses through sketching and model making. I tested the ergonomics and design with the help of my classmates. The solution is a combination of smart glasses and an app. The smart glasses function as a replacement of traditional and popular patching by dimming one lens to block vision to the strong eye. This forces the weak eye to be used. The app is used to encourage kids to use the glasses more often through games and challenges. The challenges give rewards for wearing the glasses for an extended period of time. The games are used to increase of effectiveness of the treatment. Research showed that video games like Tetris forces the eye to focus and be used more than in daily life. This solution makes the treatment experience positive instead of negative as it was with other treatments.
ContributorsMeling, Erlend Henry Olav (Author) / Shin, Dosun (Thesis director) / Feil, Magnus (Committee member) / School of Sustainability (Contributor) / The Design School (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Asthma is one of the most common chronic conditions in the United States, being diagnosed in over 20 million Americans. The condition is even more common among young children, and their academic performance and ability to attend school can be negatively impacted by poorly-managed asthma. Digital therapeutics are therapeutic interventions driven by high quality software programs to prevent, manage, or treat a medical disorder or disease. Technology in the healthcare space is rapidly improving, and smart devices are becoming more common everyday. How can digital therapeutics and evolving technology be implemented to make life easier for those that suffer from asthma and chronic obstructive pulmonary disease? My research seeks to answer the overarching question: How might we improve the day-to-day experience of children with asthma? Airie is a system of devices and products that educate both asthmatic children and their parents about the condition, facilitate self-monitoring and asthma management skills, and improve overall quality of life.
ContributorsChen, Jane Jialin (Author) / Shin, Dosun (Thesis director) / Feil, Magnus (Committee member) / The Design School (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The rise in urban populations is encouraging cities to pursue sustainable water treatment services implementing constructed treatment wetlands (CTW). This is especially important in arid climates where water resources are scarce; however, research regarding aridland CTWs is limited. The Tres Rios CTW in Phoenix, Arizona, USA, presents the tradeoff between greater water loss and enhanced nitrogen (N) removal. Previous research has suggested that water loss due to transpiration is replaced by a phenomenon termed the Biological Tide. This trend has been documented since 2011 by combining transpiration values with a nitrogen budget. Calculations were made at both the marsh and whole-system scale. The purpose of this paper is to demonstrate how the Biological Tide enhances N uptake throughout the CTW. Results indicate that about half of the nitrogen taken up by the vegetated marsh is associated with new water entering the marsh via the Biological Tide with even higher values during warmer months. Furthermore, it is this phenomenon that enhances N uptake throughout the year, on average, by 25.9% for nitrite, 9.54% for nitrate, and 4.84% for ammonium at the whole-system scale and 95.5%, 147%, and 118% within the marsh. This paper demonstrates the Biological Tide’s significant impact on enhanced N removal in an aridland CTW.
ContributorsTreese, Sawyer Matthew (Author) / Childers, Daniel L. (Thesis director) / Grimm, Nancy (Committee member) / School of Geographical Sciences and Urban Planning (Contributor) / School of Sustainability (Contributor) / School of Public Affairs (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Freshwater ecosystems are increasingly threatened by anthropogenic eutrophication (Kolzau et al., 2014) and require mitigation efforts to prevent oxygen depletion and subsequent biodiversity loss. Tres Rios Constructed Treatment Wetland (CTW) relies on wetland ecosystem functioning to reduce nutrient concentrations in order to meet regulatory guidelines. I investigated the impact of solar irradiance, temperature, and nutrient availability on aquatic net primary productivity, ecosystem respiration, and nutrient cycling using statistical analysis and quantitative modeling informed by field data generated by ASU’s Wetland Ecosystem Ecology Lab (WEEL) in partnership with the City of Phoenix Water Services Department. I found that the extent of daily solar insolation controls Aquatic Net Primary Productivity (ANPP) rates and the seasonal aquatic nutrient processing capacity of Tres Rios, resulting in the following approximate relationship: ANPP = 0.001344(W/m²) - 0.32634 (r² = 0.259; p = 0.005).
This formula was used to estimate the nutrient uptake performance of aquatic primary producers from sampling observations; ANPP accounted for 16.26 metric tons of system wide N uptake, while aquatic ER contributed 6.07 metric tons N of nighttime remineralization and 5.7 metric tons of N throughout the water column during the day. The estimated yearly net aquatic N flux is 4.49 metric tons uptake, compared to about 12 metric tons yearly N uptake by the vegetated marsh (Treese, 2019). However, not accounting for animal respiration results in an underestimation of system-wide N remineralization, and not accounting for soil processes results in an underestimation of N uptake.
This formula was used to estimate the nutrient uptake performance of aquatic primary producers from sampling observations; ANPP accounted for 16.26 metric tons of system wide N uptake, while aquatic ER contributed 6.07 metric tons N of nighttime remineralization and 5.7 metric tons of N throughout the water column during the day. The estimated yearly net aquatic N flux is 4.49 metric tons uptake, compared to about 12 metric tons yearly N uptake by the vegetated marsh (Treese, 2019). However, not accounting for animal respiration results in an underestimation of system-wide N remineralization, and not accounting for soil processes results in an underestimation of N uptake.
ContributorsEvans, Joseph Barrett (Author) / Childers, Daniel (Thesis director) / Hartnett, Hilairy (Committee member) / Watts College of Public Service & Community Solut (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
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
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 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