Fig. 4

Rapid light response curves estimated by chlorophyll a fluorescence. N+ (black circle), N− (red circle), A (green inverted triangle) and A+W (blue triangle) conditions of A–C Phaeodactylum tricornutum and D–F N. oceanica. Mean values ± standard error. qP, photochemical quenching; NPQ, non-photochemical quenching; ETR, electron transport rate. Data not normalized