Note on the Planktonic Primary Production in Fanning Island Lagoon

Abstract

A single series of representative observations indicates that both the productivity and standing crop of phytoplankton in Fanning Lagoon are much greater than reported in the lagoons of other Pacific atolls. Productivity, as measured by the radiocarbon method, averaged 9.29 mg C/m^3/hr, while chlorophyll a averaged 0.548 µg/liter. Phytoplankton, principally dinoflagellates with some diatoms and coccoid blue-greens, averaged 12.6 X 10^4 cells/liter. The relative richness of this lagoon compared with others appears to be due to the greater availability of nutrients which, in turn, is caused by the unique geographic features of the atoll.