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Temporal and spatial variations in photosynthetic physiology of diatoms during the spring bloom in the western subarctic Pacific

2009; Inter-Research; Volume: 399; Linguagem: Inglês

10.3354/meps08329

1616-1599

Naoki Yoshie, Koji Suzuki, A Kuwata, Jun Nishioka, Hiroaki Saito,

Isotope Analysis in Ecology

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 399:39-52 (2010) - DOI: https://doi.org/10.3354/meps08329 Temporal and spatial variations in photosynthetic physiology of diatoms during the spring bloom in the western subarctic Pacific Naoki Yoshie1,2,3,*, Koji Suzuki4, Akira Kuwata2, Jun Nishioka5, Hiroaki Saito2 1Division of Coastal Oceanography, Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Japan 2Tohoku National Fisheries Research Institute, Fisheries Research Agency, 3-27-5 Shinhama-cho, Shiogama 985-0001, Japan 3Japan Society for the Promotion of Science, 6 Ichibancho, Chiyoda-ku, Tokyo 102-8471, Japan 4Faculty of Environmental Earth Science, Hokkaido University, N10W5 Kita-Ku, Sapporo 060-0810, Japan 5Institute of Low Temperature Science, Hokkaido University, N19W8 Kita-Ku, Sapporo 060-0819, Japan *Email: nyoshie@sci.ehime-u.ac.jp ABSTRACT: Variations in photosynthetic parameters of phytoplankton during the spring bloom were investigated in the western subarctic Pacific. Light-saturated maximum photosynthesis rate (PBmax) and light-limited slope (αB) in the photosynthesis-irradiance (P-E) curve were almost constant in the first half of the bloom and then concurrently increased by 5 times in the latter half with a constant light-saturation index (Ek = PBmax/αB). In contrast, the maximum photochemical quantum efficiency (Fv/Fm) of the algal photosystem II increased in the first half and thereafter decreased. Water temperature significantly affected the covariation in PBmax and αB (i.e. Ek-independent variability), suggesting that dark reaction processes in photosynthesis mainly regulated the changes in the P-E parameters. Although influences of nitrate, silicic acid, and dissolved iron on the P-E parameters were not observed, the elevated ammonium levels found in the latter half of the bloom could contribute to the Ek-independent variability. There was no significant relationship among algal net growth rate, PBmax, and αB throughout the observations. Since most ecosystem models have used a constant αB, parallel changes in PBmax and αB should be taken into account in models reproducing ecosystem dynamics during spring diatom blooms. KEY WORDS: Iron · P-E curve · Photosynthesis · Spring bloom · Western North Pacific Full text in pdf format PreviousNextCite this article as: Yoshie N, Suzuki K, Kuwata A, Nishioka J, Saito H (2010) Temporal and spatial variations in photosynthetic physiology of diatoms during the spring bloom in the western subarctic Pacific. Mar Ecol Prog Ser 399:39-52. https://doi.org/10.3354/meps08329 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 399. Online publication date: January 28, 2010 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2010 Inter-Research.