Abstract
We deployed a profiling buoy system incorporating a fast repetition rate fluorometer in the western subarctic Pacific and carried out time-series observations of phytoplankton productivity from 9 June to 15 July 2006. The chlorophyll a (Chl a) biomass integrated over the euphotic layer was as high as 45–50 mg Chl a m−2 in the middle of June and remained in the 30–40 mg Chl a m−2 range during the rest of observation period; day-to-day variation in Chl a biomass was relatively small. The daily net primary productivity integrated over the euphotic layer ranged from 144 to 919 mg C m−2 day−1 and varied greatly, depending more on insolation rather than Chl a biomass. In addition, we found that part of primary production was exported to a 150-m depth within 2 days, indicating that the variations in primary productivity quickly influenced the organic carbon flux from the upper ocean. Our results suggest that the short-term variability in primary productivity is one of the key factors controlling the carbon cycle in the surface ocean in the western subarctic Pacific.
Similar content being viewed by others
References
Barlow RG, Alberte RS (1985) Photosynthetic characteristics of phycoerythrin-containing marine Synechococcus spp. 1. Responses to growth photon flux density. Mar Biol 86:63–74
Berges JA, Charlebois DO, Mauzerall DC, Falkowski PG (1996) Differential effects of nitrogen limitation on photosynthetic efficiency of photosystems I and II in microalgae. Plant Physiol 110:689–696
Buesseler KO (1998) The decoupling of production and particulate export in the surface ocean. Global Biogeochem Cycles 12:297–310
Buesseler KO, Lamborg CH, Boyd PW, Lam PJ, Trull TW, Bidigare RR, Bishop JKB, Casciotti KL, Dehairs F, Elskens M, Honda M, Karl DM, Siegel DA, Silver MW, Steinberg DK, Valdes J, Mooy BV, Wilson S (2007) Revisiting carbon flux through the ocean’s twilight zone. Science 316:567–570
Dubinsky Z, Falkowski PG, Wyman K (1986) Light harvesting and utilization by phytoplankton. Plant Cell Physiol 27:1335–1349
Falkowski PG, Raven JA (2007) Aquatic photosynthesis, 2nd edn. Princeton University Press, New Jersey
Favorite F, Dodimead AJ, Nasu K (1976) Oceanography of the subarctic Pacific region, 1960–1971. Bull Int North Pacific Fish Comm 33:1–187
Fujiki T, Hosaka T, Kimoto H, Ishimaru T, Saino T (2008) In situ observation of phytoplankton productivity by an underwater profiling buoy system: use of fast repetition rate fluorometry. Mar Ecol Prog Ser 353:81–88
Gorbunov MY, Kolber ZS, Lesser MP, Falkowski PG (2001) Photosynthesis and photoprotection in symbiotic corals. Limnol Oceanogr 46:75–85
Hama T, Miyazaki T, Ogawa Y, Iwakuma T, Takahashi M, Otsuki A, Ichimura S (1983) Measurement of photosynthetic production of a marine phytoplankton population using a stable 13C isotope. Mar Biol 73:31–36
Honda MC (2003) Biological pump in northwestern North Pacific. J Oceanogr 59:671–684
Honda MC, Watanabe S (2007) Utility of automatic water sampler to observe seasonal variability in nutrients and DIC in the northwestern North Pacific. J Oceanogr 63:349–362
Honda MC, Imai K, Nojiri Y, Hoshi F, Sugawara T, Kusakabe M (2002) The biological pump in the northwestern North Pacific based on fluxes and major components of particulate matter obtained by sediment-trap experiments (1997–2000). Deep-Sea Res II 49:5595–5625
Honda MC, Kawakami H, Sasaoka K, Watanabe S, Dickey T (2006) Quick transport of primary produced organic carbon to the ocean interior. Geophys Res Lett 33:L16603. doi:10.1029/2006GL026466
Imai K, Nojiri Y, Tsurushima N, Saino T (2002) Time series of seasonal variation of primary productivity at station KNOT (44°N, 155°E) in the sub-arctic western North Pacific. Deep-Sea Res II 49:5395–5408
Kawakami H, Honda MC (2007) Time-series observation of POC fluxes estimated from 234Th in the northwestern North Pacific. Deep-Sea Res I 54:1070–1090
Kolber Z, Falkowski PG (1993) Use of active fluorescence to estimate phytoplankton photosynthesis in situ. Limnol Oceanogr 38:1646–1665
Kolber ZS, Prášil O, Falkowski PG (1998) Measurements of variable chlorophyll fluorescence using fast repetition rate techniques: defining methodology and experimental protocols. Biochim Biophys Acta 1367:88–106
Mochizuki M, Shiga N, Saito M, Imai K, Nojiri Y (2002) Seasonal changes in nutrients, chlorophyll a and the phytoplankton assemblage of the western subarctic gyre in the Pacific Ocean. Deep-Sea Res II 49:5241–5439
Murata A, Kumamoto Y, Saito C, Kawakami H, Asanuma I, Kusakabe M, Inoue HY (2002) Impact of a spring phytoplankton bloom on the CO2 system in the mixed layer of the northwestern North Pacific. Deep-Sea Res II 49:5531–5555
Obayashi Y, Tanoue E, Suzuki K, Handa N, Nojiri Y, Wong CS (2001) Spatial and temporal variabilities of phytoplankton community structure in the northern North Pacific as determined by phytoplankton pigments. Deep-Sea Res I 48:439–469
Oxborough K, Baker NR (1997) Resolving chlorophyll a fluorescence images of photosynthetic efficiency into photochemical and non-photochemical components—calculation of qP and Fv′/Fm′ without measuring Fo′. Photosynth Res 54:135–142
Raateoja M, Seppälä J, Kuosa H (2004) Bio-optical modelling of primary production in the SW Finnish coastal zone, Baltic Sea: fast repetition rate fluorometry in Case 2 waters. Mar Ecol Prog Ser 267:9–26
Schreiber U, Schliwa U, Bilger W (1986) Continuous recording of photochemical and non-photochemical chlorophyll fluorescence quenching with a new type of modulation fluorometer. Photosynth Res 10:51–61
Smyth TJ, Pemberton KL, Aiken J, Geider RJ (2004) A methodology to determine primary production and phytoplankton photosynthetic parameters from fast repetition rate fluorometry. J Plankton Res 26:1337–1350
Steemann-Nielsen E (1952) The use of radioactive carbon (14C) for measuring organic production in the sea. Cons Int Expl Mer 18:117–140
Suggett D, Kraay G, Holligan P, Davey M, Aiken J, Geider R (2001) Assessment of photosynthesis in a spring cyanobacterial bloom by use of a fast repetition rate fluorometer. Limnol Oceanogr 46:802–810
Suggett DJ, MacIntyre HL, Kana TM, Geider RJ (2009) Comparing electron transport with gas exchange: parameterising exchange rates between alternative photosynthetic currencies for eukaryotic phytoplankton. Aquat Microb Ecol 56:147–162
Suzuki R, Ishimaru T (1990) An improved method for the determination of phytoplankton chlorophyll using N,N-dimethylformamide. J Oceanogr Soc Jpn 46:190–194
Takahashi T, Sutherland SC, Wanninkhof R, Sweeney C, Feely RA, Chipman DW, Hales B, Friederich G, Chavez F, Sabine C, Watson A, Bakker DCE, Schuster U, Metzl N, Yoshikawa-Inoue H, Ishii M, Midorikawa T, Nojiri Y, Körtzingerm A, Steinhoffm T, Hoppema M, Olafsson J, Arnarson TS, Tilbrook B, Johannessen T, Olsen A, Bellerby R, Wong CS, Delille B, Bates NR, de Baar HJW (2009) Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans. Deep-Sea Res II 56:554–577
Tsunogai S, Ono T, Watanabe S (1993) Increase in total carbonate in the western North Pacific water and a hypothesis on the missing sink of anthropogenic carbon. J Oceanogr 49:305–315
Welschmeyer NA (1994) Fluorometric analysis of chlorophyll a in the presence of chlorophyll b and pheopigments. Limnol Oceanogr 39:1985–1992
Acknowledgments
We are grateful to the captain and crew of the R/V Mirai for their support during the cruise, to the staff of Marine Works Japan Ltd. and Global Ocean Development Inc. for their on-board analysis and deck work, and to T. Nakamura (Nichiyu Giken Kogyo) for design of an underwater profiling buoy system. We also thank M.C. Honda and H. Kawakami (JAMSTEC) for sediment trap data and their interpretation of this data. The development of the profiling buoy system was supported by the SORST (Solution Oriented Research for Science and Technology) programs of the Japan Science and Technology Agency.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Fujiki, T., Matsumoto, K., Watanabe, S. et al. Phytoplankton productivity in the western subarctic gyre of the North Pacific in early summer 2006. J Oceanogr 67, 295–303 (2011). https://doi.org/10.1007/s10872-011-0028-1
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10872-011-0028-1