04 Oct 2010
04 Oct 2010
The effect of typhoon on particulate organic carbon flux in the southern East China Sea
C.-C. Hung1, G.-C. Gong1, W.-C. Chou1, C. -C. Chung1,2, M.-A. Lee3, Y. Chang3, H.-Y. Chen4, S.-J. Huang4, Y. Yang5, W.-R. Yang5, W.-C. Chung1, S.-L. Li1, and E. Laws6
C.-C. Hung et al.
C.-C. Hung1, G.-C. Gong1, W.-C. Chou1, C. -C. Chung1,2, M.-A. Lee3, Y. Chang3, H.-Y. Chen4, S.-J. Huang4, Y. Yang5, W.-R. Yang5, W.-C. Chung1, S.-L. Li1, and E. Laws6
- 1Institute of Marine Environmental Chemistry and Ecology, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 2Center for Marine Bioenvironment and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 3Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 4Department of Marine Environmental Informatics, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 5Taiwan Ocean Research Institute, National Applied Research Laboratories, Taipei, Taiwan
- 6Department of Environmental Sciences, School of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803, USA
- 1Institute of Marine Environmental Chemistry and Ecology, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 2Center for Marine Bioenvironment and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 3Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 4Department of Marine Environmental Informatics, National Taiwan Ocean University, Keelung, 20224, Taiwan
- 5Taiwan Ocean Research Institute, National Applied Research Laboratories, Taipei, Taiwan
- 6Department of Environmental Sciences, School of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803, USA
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Received: 16 Apr 2010 – Discussion started: 19 May 2010 – Revised: 16 Sep 2010 – Accepted: 21 Sep 2010 – Published: 04 Oct 2010
Abstract. Severe tropical storms play an important role in triggering phytoplankton blooms, but the extent to which such storms influence biogenic carbon flux from the euphotic zone is unclear. In 2008, typhoon Fengwong provided a unique opportunity to study the in situ biological responses including phytoplankton blooms and particulate organic carbon fluxes associated with a severe storm in the southern East China Sea (SECS). After passage of the typhoon, the sea surface temperature (SST) in the SECS was markedly cooler (∼25 to 26 °C) than before typhoon passage (∼28 to 29 °C). The POC flux 5 days after passage of the typhoon was 265 ± 14 mg C m−2 d−1, which was ∼1.7-fold that (140–180 mg C m−2 d−1) recorded during a period (June–August, 2007) when no typhoons occurred. A somewhat smaller but nevertheless significant increase in POC flux (224–225 mg C m−2 d−1) was detected following typhoon Sinlaku which occurred approximately 1 month after typhoon Fengwong, indicating that typhoon events can increase biogenic carbon flux efficiency in the SECS. Remarkably, phytoplankton uptake accounted for only about 5% of the nitrate injected into the euphotic zone by typhoon Fengwong. It is likely that phytoplankton population growth was constrained by a combination of light limitation and grazing pressure. Modeled estimates of new/export production were remarkably consistent with the average of new and export production following typhoon Fengwong. The same model suggested that during non-typhoon conditions approximately half of the export of organic carbon occurs via convective mixing of dissolved organic carbon, a conclusion consistent with earlier work at comparable latitudes in the open ocean.