Ocean acidification decreases the light‐use efficiency in an Antarctic diatom under dynamic but not constant light

• DOI: 10.1111/nph.13334
• Publication Date: 2015-02-24T08:44:58Z
• Authors: Clara J. M. Hoppe; Lena‐Maria Holtz; Scarlett Trimborn; Björn Rost
• Keywords: Ocean Acidification; Light intensity

Summary There is increasing evidence that different light intensities strongly modulate the effects of ocean acidification ( OA ) on marine phytoplankton. The aim present study was to investigate interactive and dynamic light, mimicking natural mixing regimes. Antarctic diatom C haetoceros debilis grown under two p CO 2 (390 1000 μatm) conditions (constant dynamic), latter yielding same integrated irradiance over day. To characterize between treatments, growth, elemental composition, primary production photophysiology were investigated. Dynamic reduced growth altered production, being unaffected by elevated constant yet significantly light. Interactive also observed for Chl particulate organic carbon quotas. Response patterns can be explained changes in cellular energetic balance. While energy transfer efficiency from photochemistry biomass (Φ e,C not affected it drastically Contrasting responses need considered when making predictions regarding a more stratified acidified future ocean.