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

Journal Article · Fri Dec 01 04:00:00 EST 1995 · Global Biogeochemical Cycles

DOI:https://doi.org/10.1029/95GB02149· OSTI ID:244075

Winn, C D; Campbell, L; Christian, J R ^[1]

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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, Journal Name: Global Biogeochemical Cycles Journal Issue: 4 Vol. 9; ISSN GBCYEP; ISSN 0886-6236
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CHLOROPHYLL
ECOLOGICAL CONCENTRATION
FLUORESCENCE
PACIFIC OCEAN
PHYTOPLANKTON
SEASONAL VARIATIONS