Environmental Science Undergraduate Theses

Permanent URI for this collectionhttps://hdl.handle.net/1773/53097

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Now showing 1 - 9 of 9

Clayoquot Sound Harmful Algal Blooms Investigation of Sydney Inlet - 2019
(2020-08-21) Anderbery, Alyssa; Masura, Julie; Greengrove, Cheryl
In 2014 and 2019, an unusually warm patch of water in the North Pacific called the 'Blob', came ashore in early Fall of both years. Researchers were interested to see if this warm water intruded into Sydney Inlet of Clayoquot Sound, which is located off the west coast of Vancouver Island an important source of food and income for the neighboring communities. If these warm waters intruded into the Sound, this could in-turn create favorable conditions for harmful algal blooms (HABs) to form, specifically the phytoplankton Alexandrium known to be present in this region. As a result, University of Washington Tacoma (UWT) faculty and students measured water properties and collected water samples for nutrient analysis for Clayoquot Sound for those years. Choropleth maps were created to compare relative concentrations of key nutrients used by phytoplankton, and contoured profile plots were used to determine if oceanic conditions were favorable for HABs to develop. Overall, researchers found that the 'Blob' intruded into the waters of Sydney Inlet, causing an average temperature increase of 1°C within the water body, as well as a decrease in nitrate and phosphate concentrations and an increase in fluorescence. This data suggested an increase in favorable conditions for Alexandrium corresponding to the years where the 'Blob' was present. This leads to the need for additional monitoring of shellfish beds within the area during these warm water anomalies.
Preliminary Analysis of Identifying Microplastic Polymers Using FTIR Spectroscopy from Surface Waters in the Pacific Northwest
(2024-09-19) Larino, Hannia; Masura, Julie
Microplastics (MP) are synthetic polymers < 5 mm in length. They have been found in a range of aquatic environments and inside the organs of human and aquatic species. There have been a number of studies surveying waterways for MP presence and abundance using microscopic analysis, however there is limited research findings on MP polymer identification. For this project, surface water samples were collected from 5 sites in the Pacific Northwest, extraction was done using wet peroxide oxidation, and Fourier Transformed Infrared (FTIR) spectroscopy was used to identify the polymers. Microplastics were found at all 5 sites, with the dominant polymer being polyethylene (> 65%), fragment was the most common morphology (> 74%), black was the most common color (≥ 33%), and the most common lengths were below 1 mm (>50%). Understanding the MP composition in surface waters can help direct policies related to reduction of plastic pollution in aquatic environments. Furthermore, knowing the chemical composition of polymers can help researchers understand how MPs influence the physiology and ecology of biota. Future research should investigate if spatiotemporal variables influence the results.
Validation of Pilot Protocol: Damage Scoring of Puget Sound Mollusk Shells
(2022-06-13) Doffing, Lauren; Masura, Julie; Weakland, Sandy; Burgess, Dany
The Marine Sediment Monitoring Team at the Washington State Department of Ecology observed damage to mollusk shells while studying the benthic communities of Puget Sound. A pilot protocol was written to allow researchers to quantify the damage. Two researchers independently followed the protocol, including reference photos, for a set of samples collected in 2019 from an urban bay, East Possession Sound. Two scores were given to each specimen: highest-level damage and extent of highest-level damage. An additional score was given to bivalve species: rust/stain. The sets of scores were compared to determine if the protocol yielded similar values between the two researchers. The mean for highest-level damage (0.750, P-Value2in marine waters, potentially interfere with the ability of mollusk species to build and repair their shells.
2021 Particle Grain-Size and Total Organic Content Analyses of Surface Sediments from Puget Sound and Elliott Bay near Seattle, WA
(2023-03-27) Hoang, Ethan; Masura, Julie; Greengrove, Cheryl
Seattle's Elliott Bay has been a particularly intriguing area in regards to anthropological activities and their effects on the surrounding environment. The construction of the city brought about the displacement of sediment around the bay, resulting in lower quality sediments that negatively impact the nutrient cycles in the benthic zone. This project's examination of total organic carbon and particle size in sediment serves as a baseline to which scientists can refer in monitoring future sediment health. To determine this baseline, UW Tacoma obtained sediment samples from Washington State Department of Ecology's Puget Sound Ecosystem Monitoring Program. The samples were analyzed in the lab with a Beckman-Coulter Particle Size Analyzer for sediment grain size, while the total organic content was found by the loss on ignition technique. Overall, the larger TOCs were found to correlate with smaller particle sizes. The particle size data from Elliott Bay indicates that the site ranges from sand to sandy silt. A few of the sites also had clayey silt sediments. Follow-up studies should be completed periodically to provide continuous monitoring of this bay. Any disturbances should be considered and provided to interested stakeholders.
2023 Analysis of Harmful Algae in Bed Sediments of the Puget Sound in the Salish Sea
(2024-08-19) Scheschy, Peyton; Masura, Julie; Greengrove, Cheryl
Alexandrium catenella is a toxic dinoflagellate that has two life stages, a dormant cyst form within bed sediment, and a vegetative form that swims freely in the water column. Both produce a saxitoxin that can bioaccumulate within shellfish and when ingested by mammals, could potentially lead to paralytic shellfish poisoning (PSP). This project looked at the distribution of cysts of A. catenella in the Salish Sea to inform shellfish harvesters of the potential for harmful algal blooms in their region. In order to analyze for cysts, sediment was collected at 50 stations throughout the Salish Sea. These samples were processed and stained with Primulin, then viewed under a fluorescence microscope to identify and quantify the cysts present. The average cyst counts for all stations was 8 cysts/cc(wet) and 3 cysts/cc(dry). The highest cyst counts came from Central Basin-North, and Hood Canal-Central. Both locations shared 40 cysts/cc(wet) and 12 cysts/cc(dry). The low was 0, which was shared across 20 stations. Compared to 2022, there was an increase in cysts in areas around the south Puget Sound, more specifically Hood Canal, Dyes Inlet, and the Central Basin. For 2023, there was a decrease in cysts in Bellingham Bay, which is known to be a hotspot/seedbed for A. catenella. This data was shared with stakeholders to be used to determine if increased monitoring would be needed in locations where cysts were found.
Clayoquot Sound Harmful Algal Blooms Investigation of Tofino Inlet - 2019
(2021-08-21) Kramer, Lucy; Masura, Julie; Greengrove, Cheryl
The University of Washington Tacoma has conducted yearly summer research expeditions to Clayoquot Sound along the west coast of Vancouver Island, British Columbia since in 2000. Data collected in the region examined the changing conditions in water properties at 86 different sites in Clayoquot Sound every summer. This research focused on the data collected from Tofino Inlet in 2019 and was compared to the Tofino Inlet data from 2014. Data was analyzed using GIS maps of nutrient distribution and contour profile plots to determine if rising temperatures from "the Blob", a warm water anomaly, created more favorable conditions for harmful algal blooms. The 2014 data had some stations with higher surface nutrients than 2019, while 2019 had some stations with higher bottom nutrients when compared to 2014. There was also an overall pattern in Tofino Inlet of warmer temperatures in 2019 than in 2014.
Clayoquot Sound Harmful Algal Blooms Investigation of Warn Bay to Tranquil Inlet - 2019
(2021-06-12) Whelan, Katja; Masura, Julie; Greengrove, Cheryl
A large and successful shellfish and fish industry resides in the northeastern Pacific, so when a heat anomaly now known as the "Blob" was discovered in the area there was concern about its impacts. Since many harmful algal blooms (HABs) thrive in higher temperatures, it was important to determine if the "Blob" caused more favorable environmental conditions to support increased amounts of algae in the water. Measurements were taken in 2019 for essential nutrients such as nitrates, phosphates, and silicates, as well as water properties including temperature, salinity, density, dissolved oxygen, transmissivity, and fluorescence. These were then compared to data from 2014 to verify if there was a difference between two years that the "Blob" was confirmed to have appeared. This analysis focused on a transect from Warn Bay to Tranquil Inlet in Clayoquot Sound, British Columbia, Canada. In 2019, the comparison showed a decrease in nutrients at the water's surface despite consistent values at the sea floor, as well as an increase in temperature that correlated with a decrease in transmissivity and an increase in fluorescence near the surface. This evidence supported the possibility of increased favorable conditions for HABs with the "Blob" since 2014. If persistent, future years would have to face increased risk of these HABs contaminating seafood supplies.
2023 Analysis of Microplastics in Bed Sediments of the Puget Sound in the Salish Sea
(2024-08-19) Robbins, Mia; Masura, Julie; Greengrove, Cheryl
Pollution of bays and estuaries by microplastics is an increasingly pressing concern, especially in bodies of water surrounded by densely populated areas. Microplastics have been found in waters virtually everywhere. Microplastics are known to be vectors for harmful chemicals and can impact digestion and other physiological processes in organisms. Quantifying the number of microplastics in the Puget Sound can give a clearer picture of the local scope of this issue. With this work, we monitored the levels of microplastics in sediments at 50 sites in the Puget Sound and related them to 2021. Sediments were disaggregated and density separated to isolate plastics, then samples were examined under light microscope. Plastics were characterized by type, color, and length. All samples contained microplastics. A total of 736 microplastics were counted with an average of 15 plastics per sample. 95.5% of plastics were fibers and 4.5% were films. 66.3% of plastics were clear. The dominance of clear fibers was consistent with past findings. The average microplastic length was 1.72 mm. Microplastics from 5 samples were confirmed by FT-IR spectroscopy. The most abundant type of plastic found was polypropylene followed by polyethylene. Other plastics found were styrene, vinyl chloride, nylon, BBP, and poly ethyl methacrylate. Future work will involve additional sampling of the 50 sites for monitoring of pollution levels. Acquiring data on microplastic levels can aid policy makers regarding decisions that reduce pollution.
Clayoquot Sound Harmful Algal Blooms Investigation of Herbert Inlet - 2019
(2020-08-21) Byers, Claire; Masura, Julie; Greengrove, Cheryl
Clayoquot Sound of British Columbia, Canada is a protected biosphere that has been affected by Alexandrium, a known toxic dinoflagellate, that when consumed by humans can cause paralytic shellfish poisoning. The "BLOB" events that heated the water in the Pacific Ocean in 2014 and 2019 created favorable conditions for these algae to flourish in this region. This study focused on analyzing and comparing nitrate, phosphate, and silicate levels, oceanic conditions, and water properties like temperature, salinity, density, dissolved oxygen, fluorescence, and transmissivity for Herbert Inlet in 2014 and 2019. Surface and bottom samples were collected and sent to the University of Washington School of Oceanography Marine Chemistry Lab for analysis. Meteorological data was collected from Tofino airport, and the tidal data was observed at Riley Cove. A CTD (Conductivity, Temperature, Depth) instrument was used to record the water properties as it was lowered into the water. For the nutrient data, Microsoft Excel was used to create five number summaries, and box and whisker charts. ArcGIS was used to create station maps and choropleth maps that showed the relative abundance of nutrients at each station. Data from the CTD was plotted and showed significant differences from the previous years. The results showed the nutrient levels in 2019 were lower than 2014, but the temperature in 2019 had increased by 2°C throughout the Inlet, and these warmer waters were starting to make their way into the deeper waters throughout Herbert Inlet.

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