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- Creators: Barrett, The Honors College
Description
Abstract This thesis is derived from the conservation biology field of study and seeks to chronicle and characterize the history of wolf conservation in the US, with a focus on post-ESA listing and present day events. The compelling question this thesis seeks to address is how to make long-term wolf conservation effective and feasible in the United States. An overview of wolf life history is provided, as well as a brief overview of early wolf-human interactions in Europe and the US, before reviewing the following regions in the US: Yellowstone, Idaho/Montana/Wyoming, Alaska, and Arizona. The trend identified in all regions is described as a hostile political atmosphere with particular resentment by some stakeholders towards the federal enforcement of wolf conservation via the ESA. A comparative section on Italy is provided in contrast to this US theme, as Italy tends to have a much more relaxed attitude towards wolf conservation. For success in the future of wolf conservation three suggestions are made. First, efforts to protect wolves through federal regulation are to be dismissed. Second, efforts should instead focus on education of key demographics regarding responsible environmental management and wolf management specifically. Thirdly, conservationists must actively strive to remarket the wolf as a symbol of the freedom of the west as opposed to the symbol of Washington's encroachment on state's rights.
ContributorsCampini, Conner Pennington (Author) / Smith, Andrew (Thesis director) / Gerber, Leah (Committee member) / Minteer, Ben (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-12
Description
Amphibians have been experiencing a worldwide decline that is in part caused by an infectious disease, chytridiomycosis, specific to frogs and salamanders. Globally many species have declined or gone extinct because of the pathogenic fungus Batrachochytrium dendrobatidis, also known as the amphibian chytrid or Bd. By the time Bd was discovered it was too late to stop the spread and it has now been found on almost every continent. The trade of captive amphibians, used as pets, bait, and educational animals provides an opportunity to spread Bd. Because some amphibians can carry Bd without experiencing symptoms, it is possible for even healthy looking amphibians to spread the amphibian chytrid if they are moved from one location to another. Recently, a new species Batrachochytrium salamandrivorans (Bsal) was found on salamanders. Bsal was identified before it reached the United States, prompting concern regarding its spread and a call for regulation regarding the trade of captive amphibians. There are some regulations in place controlling the trade of amphibians, but they are insufficient to stop the spread of amphibian chytrid in captive populations. A 2016 law prohibits the importation of 201 salamander species. However, there is no central organization to sample or certify if amphibians are free from Bd or Bsal. Although some stores say they test for these pathogens the tests are unregulated and not reported to any central body. If the captive amphibian trade is to go disease free, there would need to be a significant push to coordinate testing efforts. To estimate Bd's prevalence in Arizona captive amphibian populations, I contacted pet stores, bait stores, and sanctuary or educational organizations to ask if I could sample their amphibian collections. My research built on the 2008 work of Angela Picco, who sampled for the amphibian chytrid in Arizona bait shops. I found that amphibian owners were often hesitant and unwilling to participate in this research opportunity. There are multiple reasons for this hesitancy including a fear of increased regulation, the potential for reporting to a government agency (USDA), or the eventual cessation of amphibian trade. The lack of willing participants suggests there may be difficulties in coordinating future sampling efforts for Bd and Bsal.
ContributorsFadlovich, Rachel Maurine (Author) / Collins, James (Thesis director) / Minteer, Ben (Committee member) / Brus, Evan (Committee member) / School of Life Sciences (Contributor) / Department of English (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
In 2007, the Center for Biological Diversity (CBD) petitioned the United States Fish and Wildlife Service (USFWS) and the California Department of Fish and Wildlife (CDFW) to list the American pika (Ochotona princeps) as an endangered species. After several petition denials, the petition was evaluated during both 90-day, and 12-month reviews. Ultimately, both petitions were denied and the pika was not given protection under the Endangered Species Act (ESA). During the petitioning years, 2007 through 2013, there were many newspaper publications, press releases, and blog entries supporting the listing of the pika. Information published by these media ranged from misleading, to scientifically inaccurate. The public was swayed by these publications, and showed their support for listing the pika during the public comment period throughout the 12-month status review in California. While the majority of the public comments were in favor of listing the pika, there were a few letters that criticized the CBD for making a poster child out of a "cute" species. During the 12-month status review, the CDFW contacted pika experts and evaluated scientific literature to gain an understanding of the American pika's status. Seven years after the original petition, the CDFW denied listing the pika on the grounds that the species is not expected to become extinct in the next few decades. This case serves as an example where a prominent organization, the CBD, petitions to list a species that does not warrant protection. Their goal of making the pika the face of climate change failed when species was examined.
ContributorsBasso, Samantha Joy (Author) / Smith, Andrew (Thesis director) / Minteer, Ben (Committee member) / Angilletta, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
The mainstream American environmental movement has a reputation for being ethnically homogenous (i.e., white), especially within the field of conservation. Low minority involvement has been noted and discussed in the conservation literature and within environmental organizations, but these discussions aren't always informed by the explicit social justice concerns critical to understanding the complex intersection of environmental and social issues. Communities of color have expressed concern for environmental and conservation issues, but often frame those issues in a different way than is common in mainstream conservation science, a framing that we can appreciate through a deeper analysis of the values and goals of the environmental justice (EJ) movement. A more thorough inclusion of EJ principles could be an effective method to increase ethnic diversity in the field of conservation, particularly within higher education conservation programs like the Conservation Biology and Ecology (CBE) concentration at Arizona State University. This thesis frames the broader challenge of diversity in conservation, the history and current state of the conservation movement, and the history of the environmental justice movement via a literature review. I then evaluate the university's CBE program on the basis of its diversity through an analysis of demographic data on undergraduate ethnicity from the School of Life Sciences. I conclude with a series of recommendations for enhancing the diversity of ASU's CBE program moving forward.
ContributorsLiska, Kelly Margaret (Author) / Minteer, Ben (Thesis director) / Richter, Jennifer (Committee member) / Hall, Sharon (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Currently conventional Subtitle D landfills are the primary means of disposing of our waste in the United States. While this method of waste disposal aims at protecting the environment, it does so through the use of liners and caps that effectively freeze the breakdown of waste. Because this method can keep landfills active, and thus a potential groundwater threat for over a hundred years, I take an in depth look at the ability of bioreactor landfills to quickly stabilize waste. In the thesis I detail the current state of bioreactor landfill technologies, assessing the pros and cons of anaerobic and aerobic bioreactor technologies. Finally, with an industrial perspective, I conclude that moving on to bioreactor landfills as an alternative isn't as simple as it may first appear, and that it is a contextually specific solution that must be further refined before replacing current landfills.
ContributorsWhitten, George Avery (Author) / Kavazanjian, Edward (Thesis director) / Allenby, Braden (Committee member) / Houston, Sandra (Committee member) / Civil, Environmental and Sustainable Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2013-05
Characterization and Manipulation of Microbiomes From Arid Landfills for Improved Methane Production
Description
Environmentally harmful byproducts from solid waste’s decomposition, including methane (CH4) emissions, are managed through standardized landfill engineering and gas-capture mechanisms. Yet only a limited number of studies have analyzed the development and composition of Bacteria and Archaea involved in CH4 production from landfills. The objectives of this research were to compare microbiomes and bioactivity from CH4-producing communities in contrasting spatial areas of arid landfills and to tests a new technology to biostimulate CH4 production (methanogenesis) from solid waste under dynamic environmental conditions controlled in the laboratory. My hypothesis was that the diversity and abundance of methanogenic Archaea in municipal solid waste (MSW), or its leachate, play an important role on CH4 production partially attributed to the group’s wide hydrogen (H2) consumption capabilities. I tested this hypothesis by conducting complementary field observations and laboratory experiments. I describe niches of methanogenic Archaea in MSW leachate across defined areas within a single landfill, while demonstrating functional H2-dependent activity. To alleviate limited H2 bioavailability encountered in-situ, I present biostimulant feasibility and proof-of-concepts studies through the amendment of zero valent metals (ZVMs). My results demonstrate that older-aged MSW was minimally biostimulated for greater CH4 production relative to a control when exposed to iron (Fe0) or manganese (Mn0), due to highly discernable traits of soluble carbon, nitrogen, and unidentified fluorophores found in water extracts between young and old aged, starting MSW. Acetate and inhibitory H2 partial pressures accumulated in microcosms containing old-aged MSW. In a final experiment, repeated amendments of ZVMs to MSW in a 600 day mesocosm experiment mediated significantly higher CH4 concentrations and yields during the first of three ZVM injections. Fe0 and Mn0 experimental treatments at mesocosm-scale also highlighted accelerated development of seemingly important, but elusive Archaea including Methanobacteriaceae, a methane-producing family that is found in diverse environments. Also, prokaryotic classes including Candidatus Bathyarchaeota, an uncultured group commonly found in carbon-rich ecosystems, and Clostridia; All three taxa I identified as highly predictive in the time-dependent progression of MSW decomposition. Altogether, my experiments demonstrate the importance of H2 bioavailability on CH4 production and the consistent development of Methanobacteriaceae in productive MSW microbiomes.
ContributorsReynolds, Mark Christian (Author) / Cadillo-Quiroz, Hinsby (Thesis advisor) / Krajmalnik-Brown, Rosa (Thesis advisor) / Wang, Xuan (Committee member) / Kavazanjian, Edward (Committee member) / Arizona State University (Publisher)
Created2022
Description
Morphological variation among individuals has the potential to influence multiple life history characteristics such as dispersal, migration, reproductive success, and survival (Wilder et al., 2016). Research has shown that individuals that are in better "condition" can disperse or migrate further or more successfully, have greater reproductive success, and survive for longer (Wilder et al., 2016; Heidinger et al., 2010; Liao et al., 2011), particularly in years where environmental conditions are harsh (Milenkaya et al., 2014). An individual's body condition can be defined in various ways, but is most often considered an individual's energetic or immune state (Milenkaya et al., 2014). Since these traits are hard to measure directly, researchers have instead used a variety of morphological proxy variables to quantify condition such as fat score (Kaiser, 1993), weight, ratio of weight to tarsus length (Labocha et al., 2014), a scaled mass index (Peig and Green, 2009), as well as hematological indices for immune system function (Fleskes et al., 2017, Kraft et al., 2019). However, there is mixed support regarding whether these condition indices relate to life history characteristics (Wilder et al., 2016; Labocha et al., 2014), and whether the relationship is linear (Mcnamara et al., 2005; Milenkaya et al., 2014). Additionally, although some researchers use multiple morphological proxy variables for condition (e.g. Warnock and Bishop, 1998), rarely have there been direct comparisons among proxies to validate that they measure the same trait. In this investigation, we define condition as an energetic state and we attempt to measure it by comparing two indices (fat score and the scaled mass index) to validate whether they measure the same trait in our study system, the great-tailed grackle (Quiscalus mexicanus). We found that the morphological proxy variables did not correlate with each other, indicating that they were not measuring the same trait. Further, the proxy variables did not correlate with reproductive success, measured as whether a female had a fledgling and whether a male held a territory containing nests. These results improve our understanding of measures of condition in grackles, and birds in general, and the importance of condition for reproductive success - a necessary component for selection to act.
ContributorsBerens, Jennifer (Author) / Langergraber, Kevin (Thesis director) / McCune, Kelsey (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Zero-Valent Metals (ZVM) are highly reactive materials and have been proved to be effective in contaminant reduction in soils and groundwater remediation. In fact, zero-Valent Iron (ZVI) has proven to be very effective in removing, particularly chlorinated organics, heavy metals, and odorous sulfides. Addition of ZVI has also been proved in enhancing the methane gas generation in anaerobic digestion of activated sludge. However, no studies have been conducted regarding the effect of ZVM stimulation to Municipal Solid Waste (MSW) degradation. Therefore, a collaborative study was developed to manipulate microbial activity in the landfill bioreactors to favor methane production by adding ZVMs. This study focuses on evaluating the effects of added ZVM on the leachate generated from replicated lab scale landfill bioreactors. The specific objective was to investigate the effects of ZVMs addition on the organic and inorganic pollutants in leachate. The hypothesis here evaluated was that adding ZVM including ZVI and Zero Valent Manganese (ZVMn) will enhance the removal rates of the organic pollutants present in the leachate, likely by a putative higher rate of microbial metabolism. Test with six (4.23 gallons) bioreactors assembled with MSW collected from the Salt River Landfill and Southwest Regional Landfill showed that under 5 grams /liter of ZVI and 0.625 grams/liter of ZVMn additions, no significant difference was observed in the pH and temperature data of the leachate generated from these reactors. The conductivity data suggested the steady rise across all reactors over the period of time. The removal efficiency of sCOD was highest (27.112 mg/lit/day) for the reactors added with ZVMn at the end of 150 days for bottom layer, however the removal rate was highest (16.955 mg/lit/day) for ZVI after the end of 150 days of the middle layer. Similar trends in the results was observed in TC analysis. HPLC study indicated the dominance of the concentration of heptanoate and isovalerate were leachate generated from the bottom layer across all reactors. Heptanoate continued to dominate in the ZVMn added leachate even after middle layer injection. IC analysis concluded the chloride was dominant in the leachate generated from all the reactors and there was a steady increase in the chloride content over the period of time. Along with chloride, fluoride, bromide, nitrate, nitrite, phosphate and sulfate were also detected in considerable concentrations. In the summary, the addition of the zero valent metals has proved to be efficient in removal of the organics present in the leachate.
ContributorsPandit, Gandhar Abhay (Author) / Cadillo – Quiroz, Hinsby (Thesis advisor) / Olson, Larry (Thesis advisor) / Boyer, Treavor (Committee member) / Arizona State University (Publisher)
Created2019