Plastic Debris in Deep-Sea Canyon, Estuarine, and Shoreline Sediments
| dc.contributor.author | Jones, Ellie Sophie | |
| dc.date.accessioned | 2019-05-20T18:38:46Z | |
| dc.date.available | 2019-05-20T18:38:46Z | |
| dc.date.issued | 2019-05 | |
| dc.description | Submitted to the Undergraduate Library Research Award scholarship competition: (2019). 66 p. | en_US |
| dc.description.abstract | Recent calculations estimate there are currently 5.25 trillion plastic particles afloat in the ocean. Many of these are characterized as microplastics <5mm in diameter. Studies from the past decade have shown that no ecosystem is exempt from plastic contamination. This study examined box core sediment samples from Norfolk Canyon, box core and PONER grab samples from the Coos Bay Estuary, and belt transects along the Oregon shoreline to investigate plastic in marine sediments. The average microplastic density in Norfolk Canyon was 12.95 particles per liter of sediment within the canyon, and 2.04 particles per liter of sediment on the adjacent continental slope. I hypothesize that canyons concentrate microplastics due to down-canyon turbidity currents. In the Coos Bay Estuary, the highest density of microplastics was found in the mouth of the estuary. I hypothesize that plastics can sink due to the front created at the intersection between oceanic and estuarine waters, and can become concentrated around geologically structured areas in the estuary mouth. Using belt transects, I surveyed plastic densities on the northern and southern sides of Yaquina Head, Cape Perpetua, and Cape Blanco. Higher plastic densities were found on the southern beaches in each case. I hypothesize that microplastics may be carried onshore by winds, which blow onto southern-facing beaches on Oregon's coast during the winter. It is important to understand where plastics and concentrated in marine sediments in order to form hypotheses about both horizontal and vertical transport of plastic in the ocean. | en_US |
| dc.identifier.uri | https://hdl.handle.net/1794/24578 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Oregon | en_US |
| dc.rights | Creative Commons BY-NC-ND 4.0-US | en_US |
| dc.title | Plastic Debris in Deep-Sea Canyon, Estuarine, and Shoreline Sediments | en_US |
| dc.type | Thesis / Dissertation | en_US |