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Title: Seasonal variability in the phytoplankton community of the North Pacific Subtropical Gyre

Journal Article · · Global Biogeochemical Cycles
DOI:https://doi.org/10.1029/95GB02149· OSTI ID:244075
; ;  [1]
  1. Univ. of Hawaii, Manoa, HI (United States); and others

This study was performed to assess seasonal cycles in fluorescence and chlorophyll concentrations in the North Pacific Subtropical Gyre. Flow cytometry and continuous in situ flash fluorescence were used to measureme in situ fluorescence, extracted chlorophyll a, primary productivity, extracted adenosine 5-triphosphate, and fluorescence per cell. Chlorophyll a concentrations increased in winter and decreased in summer in the upper euphotic zone. In the lower euphotic zone, however, chlorophyll a concentrations increased in spring and decreased in fall. The winter increase in the upper zone appeared to be caused by photoadaptation to decreased light intensity. The seasonal variation in the lower zone was indicative of a change in primary production rate and phytoplankton biomass due to increased light intensity. Based on the similarities of these observations to satellite data and other regional data, the seasonal patterns identified in this study may be common to large areas of subtropical oceans. 52 refs., 7 figs., 2 tabs.

OSTI ID:
244075
Journal Information:
Global Biogeochemical Cycles, Vol. 9, Issue 4; Other Information: PBD: Dec 1995
Country of Publication:
United States
Language:
English