MICROPLANKTON COMMUNITY STRUCTURE AND CARBON BIOMASS IN RELATION TO ENVIRONMENTAL GRADIENTS IN THE GULF OF MEXICO (SUMMER-FALL, 2021).

The Gulf of Mexico (GOM) experiences multiple anthropogenic stressors including ocean acidification, eutrophication, harmful algal blooms (HABs), and large-scale hypoxia. Sea surface temperatures across the GOM are increasing at a rate twice that of the global ocean. Climate drivers have generally been associated with loss of ocean biodiversity and declines in ecological resilience, but less research is available on the effect of climate change on lower trophic level organisms. Protists are an ecologically diverse group of single-celled eukaryotes that play central roles as primary producers, consumers, decomposers, and that serve as the link for energy transfer to higher trophic levels. Changes in protistan assemblage patterns across the GOM regions can be used as an indication of ecosystem health. HAB taxa are of particular concern in areas where nutrient-rich freshwater input is intensified (e.g., Mississippi river, upwelling regions). This study explores the protistan community across gradients of pCO₂, temperature, and nutrients in the GOM. Biological samples were collected during summer/fall of 2021 from locations throughout the GOM as part of the fourth Gulf of Mexico Ecosystems and Carbon Cruise (GOMECC-4). Seawater samples were used for analyzing microplankton community composition via automated-imaging microscopy (FlowCam) and identified by functional groups (phototroph, mixotroph, and heterotroph). The goal of this research is to characterize spatial patterns in protistan microplankton (15 – 200 µm) and estimate carbon stocks and diversity across the GOM.

Presentation Preference: Poster

Primary Presenter: Lucy Roussa, North Carolina State University (lroussa@ncsu.edu)

Authors:

Lucy Roussa, North Carolina State University  (lroussa@ncsu.edu)

Miranda Hart, North Carolina State University  (msirby@ncsu.edu)

Beth Stauffer, University of Louisiana at Lafayette  (beth.stauffer@louisiana.edu)

Leticia Barbero, University of Miami  (Leticia.Barbero@noaa.gov)

Astrid Schnetzer, North Carolina State University  (aschnet@ncsu.edu)