Influence of mercury salts on the condition of algae as studied by fluorescence methods

摘要

By measuring light curves of chlorophyll fluorescence, we studied the effect of methylmercury at low concentrations (10~(-7) mol) on the parameters of chlorophyll a fluorescence in the microalgae Scenedesmus quadricauda. It was shown that the toxicant at low concentration diminishes the relative rate of non-cyclic electron transport of photosystems 2, decreases the coefficient of light energy utilization (α) and reduces the intensity of saturating light (E_s). Similar effects of exposure to mercury salts are shown for natural phytoplankton of the Moskva River. The method of measuring the light curve parameters in algal cells can be used to determine changes at early stages of exposure during monitoring in natural conditions.