Single-Turnover Variable Chlorophyll Fluorescence as a Tool for Assessing Phytoplankton Photosynthesis and Primary Productivity: Opportunities, Caveats and Recommendations

• DOI: 10.3389/fmars.2021.690607
• Publication Date: 2021-07-14T07:39:38Z
• Authors: Nina Schuback; Philippe D. Tortell; Ilana Berman-Frank; Douglas A. Campbell; Aurea Ciotti; Emilie Courtecuisse; Zachary K. Erickson; Tetsuichi Fujiki; Kimberly Halsey; Anna E. Hickman; Yannick Huot; Maxime Y. Gorbunov; David J. Hughes; Zbigniew S. Kolber; C. Mark Moore; Kevin Oxborough; Ondřej Prášil; Charlotte M. Robi...; Thomas J. Ryan-Keogh; Greg Silsbe; Stefan Simis; David J. Suggett; Sandy Thomalla; Deepa R. Varkey
• Keywords: Comparability

Phytoplankton photosynthetic physiology can be investigated through single-turnover variable chlorophyll fluorescence (ST-ChlF) approaches, which carry unique potential to autonomously collect data at high spatial and temporal resolution. Over the past decades, significant progress has been made in development application of ST-ChlF methods aquatic ecosystems, interpretation resulting observations. At same time, however, an increasing number sensor types, sampling protocols, processing algorithms have created confusion uncertainty among users, with a growing divergence practice different research groups. In this review, we assist existing upcoming user community by providing overview current approaches consensus recommendations for use measurements examine in-situ phytoplankton productivity photo-physiology. We argue that consistency adherence basic operational quality control standards is critical ensuring inter-comparability. Large datasets inter-comparable globally coherent observations hold reveal large-scale patterns trends photo-physiology, rates bottom-up controls on primary productivity. As such, they great provide invaluable physiological scales relevant validation ecosystem models remote sensing algorithms.