Sponsor
Portland State University. Department of Biology
First Advisor
Anne W. Thompson
Term of Graduation
Spring 2024
Date of Publication
7-8-2024
Document Type
Thesis
Degree Name
Master of Science (M.S.) in Biology
Department
Biology
Language
English
Subjects
California Current, Microbial ecology, Phytoplankton, Synechococcus
Physical Description
1 online resource (vi, 65 pages)
Abstract
The Northern California Current system is a productive coastal ecosystem encompassing a variety of temporal and spatial features. The photosynthetic microbial community plays a crucial role in supporting the rich ecosystem and its economically important fisheries. My research integrates data across location and two years to investigate the community composition of two major phytoplankton groups in this system: picocyanobacteria and photosynthetic picoeukaryotes (PPE). The abundances and sizes of the phytoplankton were measured using flow cytometry. I found PPE present at similar concentrations in both summer and winter seasons. Abundances of both PPE and picocyanobacteria were comparable in the winter, but picocyanobacteria were much more abundant in the summer. The relationship between the two types varied across on- to off-shore transects with different coastal bathymetry. Abundances of both types of cells increased with distance from shore. Cell size also varied by season with more small cells present during a marine heat wave summer (2023) than a more typical summer (2022). Because the primary producers are the foundation of the rest of the ecosystem, understanding the phytoplankton community that underlies this important ecological system will help inform management decisions and future ecosystem models in the context of climate change.
Rights
© 2024 Kristin E. Forgrave
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
Persistent Identifier
https://archives.pdx.edu/ds/psu/42429
Recommended Citation
Forgrave, Kristin E., "Phytoplankton Community Dynamics in the Northern California Current System" (2024). Dissertations and Theses. Paper 6676.
Comments
Funding for this project was provided by Simons Foundation award LS-ECIAMEE00001481 and NSF OCE-1851412 to AWT. SPECTRA cruise funding was provided by NSF awards OCE-2125407 and OCE-2125408.