Complete DATASET_Contrasting nonphotochemical quenching patterns under high light and darkness aligns with light niche occupancy in Arctic diatoms

• Main Authors: Croteau, Dany, Guérin, Sébastien, Bruyant, Flavienne, Ferland, Joannie, Campbell, Douglas A, Babin, Marcel, Lavaud, Johann
• Format: Dataset
• Language: unknown
• Published: figshare 2020
• Subjects: 60701 Phycology incl. Marine Grasses; FOS Biological sciences; Marine Biology; 69902 Global Change Biology; Arctic; Arctic Ocean; Sea ice
• Online Access: https://dx.doi.org/10.6084/m9.figshare.12966773; https://figshare.com/articles/dataset/Complete_DATASET_Contrasting_nonphotochemical_quenching_patterns_under_high_light_and_darkness_aligns_with_light_niche_occupancy_in_Arctic_diatoms/12966773

Over the seasons, Arctic diatom species occupy shifting habitats defined by contrasting light climates, constrainedby snow and ice cover dynamics interacting with extreme photoperiod and solar angle variations. HowArctic diatom photoadaptation strategies differ across their heterogeneous light niches remains a poorly documentedbut crucial missing link to anticipate Arctic Ocean responses to shrinking sea-ice and increasing light. Toaddress this question, we selected five Arctic diatom species with diverse life traits, representative of distinct lightniches across the seasonal light environment continuum: from snow-covered dimly lit bottom ice to summerstratified waters. We studied their photoacclimation plasticity to two growth light levels and the subsequentresponses of their nonphotochemical quenching (NPQ) and xanthophyll cycle to both dark incubations and lightshifts. We deciphered NPQ and xanthophyll cycle tuning in darkness and their light-dependent induction kinetics,which aligned with species’ light niche occupancy. In ice-related species, NPQ was sustained in darkness andits induction was more reactive to moderate light shifts. Open-water species triggered strong NPQ induction indarkness and reached higher maximal NPQ under high light. Marginal ice zone species showed strong adaptationto light fluctuations with a dark response fine-tuned depending upon light history. We argue these traits areanchored in diverging photoadaption strategies fostering Arctic diatom success in their respective light niches.