Effects of solar irradiation on motility and pigmentation of three species of phytoplankton

Abstract

The effects of solar irradiation on motility and pigmentation of two Cryptomonas species and Euglena gracilis were investigated in a comparative field study in Erlangen (200 m above sea level) and on the Zugspitze (2957 m above sea level). The experiments showed that the pigments of all organisms were bleached faster and cell motility was also impaired faster at the Zugspitze site than in Erlangen. Eliminating the u.v.-B irradiation provided some protection of the cells: bleaching and immobility occurred later. These results indicate that slightly increased solar u.v.-B levels, which are expected to occur due to the partial depletion of the ozone layer, may have severe effects on phytoplankton populations.