Alleviation of solar ultraviolet radiation (UVR)-induced photoinhibition in diatom Chaetoceros curvisetus by ocean acidification

• Published in: Journal of the Marine Biological Association of the United Kingdom
• Main Authors: Chen, Heng, Guan, Wanchun, Zeng, Guoquan, Li, Ping, Chen, Shaobo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2014
• Subjects: Aquatic Science; Ocean acidification
• Online Access: http://dx.doi.org/10.1017/s0025315414001568; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315414001568

The study aimed to unravel the interaction between ocean acidification and solar ultraviolet radiation (UVR) in Chaetoceros curvisetus . Chaetoceros curvisetus cells were acclimated to high CO 2 (HC, 1000 ppmv) and low CO 2 concentration (control, LC, 380 ppmv) for 14 days. Cell density, specific growth rate and chlorophyll were measured. The acclimated cells were then exposed to PAB (photosynthetically active radiation (PAR) + UV-A + UV-B), PA (PAR + UV-A) or P (PAR) for 60 min. Photochemical efficiency (ΦPSII), relative electron transport rate (rETR) and the recovery of ΦPSII were determined. HC induced higher cell density and specific growth rate compared with LC. However, no difference was found in chlorophyll between HC and LC. Moreover, ΦPSII and rETRs were higher under HC than LC in response to solar UVR. P exposure led to faster recovery of ΦPSII, both under HC and LC, than PA and PAB exposure. It appeared that harmful effects of UVR on C. curvisetus could be counteracted by ocean acidification simulated by high CO 2 when the effect of climate change is not beyond the tolerance of cells.