Pigment Diversity in Freshwater Phytoplankton. I. A Comparison of Spectrophotometric and Paper Chromatographic Methods

Spectrophotometric and paper chromatographic analyses of the pigments in the phytoplankton were made from early spring till the end of summer in two small Dutch freshwater lakes. It was found that pigment diversity cannot be adequately estimated by MARGALEF'S pigment ratio nor by polychromatic spectrophotometric methods. The pigments detected with the paper chromatographic method were: chlorophyll‐ a , chlorophyll‐ b , chlorophyll‐ c , phaeophytin‐ a (traces), phaeophorbide‐ a , Mg‐containing chlorophyll‐derivatives, carotene, lutein, violaxanthin, neoxanthin (traces), fucoxanthin, diadinoxanthin, diatoxanthin (traces), peridinin and keto‐carotenoids (traces). It is suggested to distinguish between a richness‐component and an evenness‐component of pigment diversity.