Enhancement of diatom growth and phytoplankton productivity with reduced O₂ availability is moderated by rising CO₂.

ABSTRACT: Many marine organisms are exposed to decreasing O₂ levels due to warming-induced expansion of hypoxic zones and ocean deoxygenation (DeO₂). Nevertheless, effects of DeO₂ on phytoplankton have been neglected due to technical bottlenecks on examining O₂ effects on O₂-producing organisms. Here we show that lowered O₂ levels increased primary productivity of a coastal phytoplankton assemblage, and enhanced photosynthesis and growth in the coastal diatom Thalassiosira weissflogii. Mechanistically, reduced O₂ suppressed mitochondrial respiration and photorespiration of T. weissflogii, but increased the efficiency of their CO₂ concentrating mechanisms (CCMs), effective quantum yield and improved light use effi

SUBMITTER: Sun JZ 

PROVIDER: S-EPMC8760321 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature