Seasonality in the community composition and food web structure of plankton in the Strait of Georgia
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: McEwan, Nicole
issued: 2022-08-23T22:23:13Z
issued: 2022
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: The Strait of Georgia (SoG) is a productive, temperate, and coastal ecosystem in the Northeast Pacific Ocean. Throughout a year in the SoG, plankton productivity and community structure have strong seasonal variations. However, the diverse range of plankton species, trophic processes, and interactions are often over-simplified in food web models. The objectives of this study were to: a) describe the seasonal trends in plankton community composition, biomass, and vertical distribution; b) represent the seasonal food web structure of the plankton community; and c) compare this complex and seasonal modelling approach to a more common and simplified approach. In the spring, diatoms dominate the plankton biomass in the SoG, leading to high primary productivity and fueling zooplankton growth. In summer, primary production is nutrient limited, leading to a decline in diatom biomass and increased mixotrophic flagellate dominance. Zooplankton biomass, dominated by large crustaceans including copepods, amphipods, and euphausiids, peaks and their diets shift to become more omnivorous. In winter, plankton biomass and productivity are low. Based on these seasonal trends, I constructed a food web model for each season (spring, summer, and winter), with the plankton community represented by ten mesozooplankton groups, two mixotrophic microzooplankton groups, one phytoplankton group, one heterotrophic bacteria group, and one detrital group. The spring food web is mostly fueled by high diatom primary production. However, the microbial loop, consisting of detritus, heterotrophic bacteria, and microzooplankton, shifts to become an important energy source for the system under limiting conditions in the summer and winter food webs. These structural changes throughout a year could have important implications and insights for higher trophic levels, such as into the seasonal food availability and quality for plankivorous fish. Finally, I compared this detailed seasonal approach to plankton…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/82490
note: Seasonality in the community composition and food webstructure of plankton in the Strait of GeorgiabyNicole McEwanB. Engineering, University of Guelph, 2017A THESIS SUBMITTED IN PARTIAL FULFILLMENTOF THE REQUIREMENTS FOR THE DEGREE OFMaster of ScienceinTHE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES(Oceanography)The University of British Columbia(Vancouver)August 2022© Nicole McEwan, 2022The following individuals certify that they have read, and recommend to the Faculty of Gradu-ate and Postdoctoral Studies for acceptance, the thesis entitled:Seasonality in the community composition and food web structure of plank-ton in the Strait of Georgiasubmitted by Nicole McEwan in partial fulfillment of the requirements for the degree of Masterof Science in Oceanography.Examining Committee:Dr. Richard Pawlowicz, Professor, Earth, Ocean and Atmospheric Sciences, UBCSupervisorDr. Maria Teresa Maldonado, Professor, Earth, Ocean and Atmospheric Sciences, UBCSupervisory Committee MemberDr. Evgeny Pakhomov, Professor, Earth, Ocean and Atmospheric Sciences, UBCSupervisory Committee MemberDr. Brian Hunt, Assistant Professor, Earth, Ocean and Atmospheric Sciences, UBCAdditional ExamineriiAbstractThe Strait of Georgia (SoG) is a productive, temperate, and coastal ecosystem in the NortheastPacific Ocean. Throughout a year in the SoG, plankton productivity and community structurehave strong seasonal variations. However, the diverse range of plankton species, trophic pro-cesses, and interactions are often over-simplified in food web models. The objectives of thisstudy were to: a) describe the seasonal trends in plankton community composition, biomass,and vertical distribution; b) represent the seasonal food web structure of the plankton commu-nity; and c) compare this complex and seasonal modelling approach to a more common andsimplified approach. In the spring, diatoms dominate the plankton biomass in the SoG, leadingto high primary productivity and fueling zooplankton growth. In summer…
has type: Thesis/Dissertation
date issued: 2022-11
is shown at: 10.14288/1.0417484
language: eng
degree discipline: Oceanography
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Pawlowicz, Rich
type: Text
identifier URI: http://hdl.handle.net/2429/82490