Filtering by
- All Subjects: Climate Change
- All Subjects: Ecology
- Creators: School of 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.
To mitigate climate change, carbon needs to be removed from the atmosphere and stored for thousands of years. Currently, carbon removal and storage are voluntarily procured, and longevity of storage is inconsistently defined and regulated. Clauses can be added to procurement contracts to require long-term management and increase the durability of storage. Well-designed and properly enforced contracts can pave the way to future regulation for long-term carbon management.
Climate change is impacting fisheries through ecological shifts altering the geographical distribution and quantity of fish species. About 60% of United States fish caught by volume is caught in the Alaska region, with Alaska's economy dependent on fisheries. Additionally, fisheries are an important source of employment for many Alaskan communities. Therefore, it is important to have policies and strategies in place to prepare for ongoing climate impacts. One step to support better tailoring policy to support those most likely to be negatively impacted is to identify the fishing communities most vulnerable to climate change. This study uses data on vulnerable fish species and fishery catch by species and community to identify what communities are most vulnerable to changing climate conditions. I identify 26 communities that are fishing climate vulnerable species. I then use vulnerable fish species revenue data to identify communities most at risk either because they generate a substantial amount of revenue from these species or a substantial proportion of their total revenue is derived from these species. Using species-specific revenue, I show that Sablefish contribute the most to this vulnerability.
This thesis will examine possible connection points between the health of a local environmental/climate news ecosystem and that local community’s belief in and vulnerability to the effects of climate change in Central Appalachia and Northern Virginia. The three counties that will be studied in Virginia are Arlington, Buchanan and Wise Counties. This research will be mainly a hypothesis-generating descriptive analysis of data, coupled with both interviews with researchers and local experts, in addition to observations from relevant literature about the possible connections between availability of environmental news with climate change, institutional belief and climate vulnerability data. The local history of resource extraction will also be explored. The point of this thesis is not to prove that a lack of access to strong, locally focused climate and environmental news increases vulnerability to the effects of climate change (although it does raise this as a possibility). Rather, it is to continue a conversation with journalists, media professionals and climate professionals about how to approach understanding and engaging groups left out of the climate conversation and groups who've been traditionally underserved by news media when it comes to climate information and appeals for institutional trust. This conversation is already happening, especially when it comes to the importance of the health of local, community focused news in general in Appalachia, but given the urgency and scale of the climate crisis, merits continuation and some inquiry into environmental news.