October 19, 2022

12:00pm, PST 158 HH and Zoom

Allison Moreno
Atmospheric and Oceanic Sciences, UCLA

" Distinct Biome Controls of Phytoplankton Respiration "

Climate-driven depletion of ocean oxygen strongly impacts the global cycles of carbon and nutrients as well as the survival of many animal species. A key uncertainty for predicting future ocean oxygen levels is the response and feedback of organic matter respiration demand. One poorly constrained component of the respiration demand is the oxygen-to-carbon remineralization ratio—the respiration quotient. We directly quantified along a meridional section of the Atlantic Ocean and compared to previous Pacific Ocean observations. We demonstrate significant regional shifts in the respiration quotient and a two-basin average of 1.16. Basin and regional variation in the respiration quotient were positively linked to environmental conditions, and plankton size structure. These observations suggest a complex regulation of the respiration quotient with important implications for the regional coupling of carbon and oxygen cycling.

The Department of Ecology and Evolutionary Biology at UCLA acknowledges our presence on the traditional, ancestral and unceded territory of the Gabrielino/Tongva peoples.

Host: Colin Kremer