Phycosphere pH of unicellular nano- and micro- phytoplankton cells and consequences for iron speciation.

ABSTRACT: Surface ocean pH is declining due to anthropogenic atmospheric CO₂ uptake with a global decline of ~0.3 possible by 2100. Extracellular pH influences a range of biological processes, including nutrient uptake, calcification and silicification. However, there are poor constraints on how pH levels in the extracellular microenvironment surrounding phytoplankton cells (the phycosphere) differ from bulk seawater. This adds uncertainty to biological impacts of environmental change. Furthermore, previous modelling work suggests that phycosphere pH of small cells is close to bulk seawater, and this has not been experimentally verified. Here we observe under 140 μmol photons·m^-2·s^-1 the phycosphere pH of Chlamydomonas concordia (5 µm diameter), Emiliania huxleyi (5 

SUBMITTER: Liu F 

PROVIDER: S-EPMC9478132 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature