Ocean acidification stimulates particulate organic carbon accumulation in two Antarctic diatom species under moderate and high natural solar radiation

Impacts of rising atmospheric CO2 concentrations and increased daily irradiances from enhanced surface water stratification on phytoplankton physiology in the coastal Southern Ocean remain still unclear. Therefore, in the two Antarctic diatoms Fragilariopsis curta and Odontella weissflogii, the effe...

Full description

Saved in:
Bibliographic Details
Published in:Journal of phycology 2018-08, Vol.54 (4), p.505-517
Main Authors: Heiden, Jasmin P., Thoms, Silke, Bischof, Kai, Trimborn, Scarlett, Raven, J.
Format: Article
Language:English
Subjects:
Acidification
Bacillariophyceae
Blooms
Carbon
Carbon dioxide
Carbon sequestration
climate change
CO 2
Coastal environments
Density stratification
Diatoms
Fitness
light
multiple stressors
Ocean acidification
Organic carbon
Particulate organic carbon
Photochemistry
photophysiology
Photosensitivity
Photosynthesis
Photosystem II
Physiology
Phytoplankton
Plankton
Polar environments
Primary production
Quotas
Reaction centers
Regular
Solar radiation
Southern Ocean
Species
Stratification
Surface water
Water stratification
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Impacts of rising atmospheric CO2 concentrations and increased daily irradiances from enhanced surface water stratification on phytoplankton physiology in the coastal Southern Ocean remain still unclear. Therefore, in the two Antarctic diatoms Fragilariopsis curta and Odontella weissflogii, the effects of moderate and high natural solar radiation combined with either ambient or future pCO2 on cellular particulate organic carbon (POC) contents and photophysiology were investigated. Results showed that increasing CO2 concentrations had greater impacts on diatom physiology than exposure to increasing solar radiation. Irrespective of the applied solar radiation regime, cellular POC quotas increased with future pCO2 in both diatoms. Lowered maximum quantum yields of photochemistry in PSII (Fv/Fm) indicated a higher photosensitivity under these conditions, being counteracted by increased cellular concentrations of functional photosynthetic reaction centers. Overall, our results suggest that both bloom‐forming Antarctic coastal diatoms might increase carbon contents under future pCO2 conditions despite reduced physiological fitness. This indicates a higher potential for primary productivity by the two diatom species with important implications for the CO2 sequestration potential of diatom communities in the future coastal Southern Ocean.
ISSN:0022-3646
1529-8817
DOI:10.1111/jpy.12753