Ocean acidification conditions increase resilience of marine diatoms

• Published in: Nature communications 2018-06, Vol.9 (1), p.2328-10, Article 2328
• Main Authors: Valenzuela, Jacob J., López García de Lomana, Adrián, Lee, Allison, Armbrust, E. V., Orellana, Mónica V., Baliga, Nitin S.
• Format: Article
• Language: English
• Subjects: 38; 38/39; 38/43; 631/158/1745; 631/553/1833; 631/553/2715; 704/106/829/826; Acidification; Adaptation, Physiological; Bacillariophyta; Carbon dioxide; Carbon Dioxide - analysis; Climate Change; Collapse; Diatoms - genetics; Diatoms - growth & development; Diatoms - physiology; Diurnal; Diurnal variations; Dosage; Ecosystem; Environmental changes; Gene Expression; Humanities and Social Sciences; Hydrogen-Ion Concentration; Marine ecosystems; Microorganisms; multidisciplinary; Nitrogen; Ocean acidification; Oceans; Oceans and Seas; Phase matching; Plankton; Primary production; Resilience; Science; Science (multidisciplinary); Seawater - adverse effects; Seawater - chemistry; Stress, Physiological; Time Factors; Ultraviolet Rays
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-04742-3

The fate of diatoms in future acidified oceans could have dramatic implications on marine ecosystems, because they account for ~40% of marine primary production. Here, we quantify resilience of Thalassiosira pseudonana in mid-20th century (300 ppm CO 2 ) and future (1000 ppm CO 2 ) conditions that cause ocean acidification, using a stress test that probes its ability to recover from incrementally higher amount of low-dose ultraviolet A (UVA) and B (UVB) radiation and re-initiate growth in day–night cycles, limited by nitrogen. While all cultures eventually collapse, those growing at 300 ppm CO 2 succumb sooner. The underlying mechanism for collapse appears to be a system failure resulting from “loss of relational resilience,” that is, inability to adopt physiological states matched to N-availability and phase of the diurnal cycle. Importantly, under elevated CO 2 conditions diatoms sustain relational resilience over a longer timeframe, demonstrating increased resilience to future acidified ocean conditions. This stress test framework can be extended to evaluate and predict how various climate change associated stressors may impact microbial community resilience. Diatoms account for 40% of marine primary production and their sensitivity to ocean acidification could have ecosystem-wide consequences. Here, the authors developed and applied a stress test, demonstrating that resilience of diatoms increases significantly in ocean acidification conditions.