[All-postdocs] Bioseminar - Clarissa Karthauser

[Ana Velez]

Woods Hole Oceanographic Institution
Biology Department Seminar

Thursday, April 30, 2026 - 12:00 pm
Redfield Auditorium

Clarissa Karthauser
Postdoctoral Fellow, WHOI

Marine Snow and Fecal Pellets: Linking Particle Traits to Carbon Transfer Efficiency
Sinking particles are central to the biological carbon pump, transporting organic carbon from the sunlit ocean surface to depth, yet their diversity in origin, structure, and composition makes their contribution to carbon export difficult to predict. I will present two complementary datasets that examine how particle morphology relates to carbon transport and remineralization. The first dataset links individual marine particles' size and image-derived traits with sinking velocity, carbon content, chemical and genetic composition, testing a new approach for predicting in situ carbon concentrations and flux from underwater imaging. The second dataset focuses on zooplankton fecal pellets, characterizing freshly produced pellets by morphology, carbon content, sinking velocity, taxonomic composition, and microbial activity. Results show that pellet structure strongly influences carbon transport: smaller pellets exhibited disproportionately high sinking velocities and carbon contents, while microbial remineralization rates were generally low and more closely related to surface-area-dependent properties than to composition. Together, these datasets highlight that individual particle morphology and structural integrity are key controls on export efficiency, remineralization, and the overall contribution of distinct particle types to ocean carbon flux.

Biology Seminar Web Page<https://www.whoi.edu/what-we-do/understand/departments-centers-labs/bio/bio-highlights-events/>

For questions, contact:

Ana Maria Velez
Biology Pre-Award Administrative Associate
Ph: 508-289-2334
[signature_1005462319]

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