MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 627:13-31 (2019) - DOI: https://doi.org/10.3354/meps13083 Uncertainties in variable fluorescence and 14C methods to estimate primary production: a case study in the coastal waters off the Korean peninsula Eunho Ko1,2, Jisoo Park1,2, Maxim Y. Gorbunov3, Sinjae Yoo2,4,* 1Division of Polar Ocean Environment, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-Gu, Incheon 21990, Republic of Korea 2University of Science and Technology, 217 Gajeongh-ro, Daejeon 34113, Republic of Korea 3Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey 08901, USA 4Jeju Marine Research Section, Korea Institute of Ocean Science & Technology, 2670 lljudong-ro, Gujwa-eup, Jeju-si, Jeju-do 63349, Republic of Korea *Corresponding author: sjyoo@kiost.ac.kr ABSTRACT: To understand what controls the decoupling of photosynthetic electron transfer and carbon fixation in natural phytoplankton communities, we compared the primary production rates estimated by 14C uptake and fast repetition rate fluorometry (FRRF) in Korean waters under diverse environmental conditions. Our comparison showed that these 2 methods produce consistent results, with the FRRF method systematically yielding 1.9 times higher values than the 14C method. To quantify the potential factors that contribute to this discrepancy, we analyzed the variability in the electron requirement for carbon fixation, which showed a wide range of 5.5-71.3 mol electrons (mol CO2)-1, in relation to environmental variables. The analysis revealed that nutrient availability and the state of stratification may be the major factors that control variability in the electron requirement for carbon fixation. The strong dependence on nitrogen suggests that photosynthetic processes and phytoplankton growth are not in balance in natural communities. Based on the relationship with environmental variables, we propose a regional algorithm for the electron requirement for carbon fixation, which markedly improves FRRF-based measurements of primary production in this geographical area. KEY WORDS: Primary production · 14C · Variable fluorescence · Electron requirement for carbon fixation · Electron transfer rate · Fast repetition rate fluorometry Full text in pdf format PreviousNextCite this article as: Ko E, Park J, Gorbunov MY, Yoo S (2019) Uncertainties in variable fluorescence and 14C methods to estimate primary production: a case study in the coastal waters off the Korean peninsula. Mar Ecol Prog Ser 627:13-31. https://doi.org/10.3354/meps13083 Export citation Mail this link - Contents Mailing Lists - RSS Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 627. Online publication date: September 26, 2019 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2019 Inter-Research.