Phycoerythrin in the deeper water layer of a stratified eutrophic lake: An application of bile pigment in determining the standing crop of blue‐green algae

Absorption spectra of intact phytoplankton cells collected from a stratified eutrophic lake in Japan were studied. Vertical and seasonal changes in the content of phycoerythrin of blue‐green algae were indicated on the basis of the absorbance at 560 nm in those spectra. The possibility of an application of the technique to estimate the standing crop of blue‐green algae in the phytoplankton community was discussed.