Home – Home – Jornals – Contemporary Problems of Ecology 2023 number 3

The changes in the specific growth rate, fluorescent, cytometric and morphological parameters of the green microalgae Dunaliella salina were evaluated when copper ions were added to the culture medium at a concentration of 0-3750 µg/L. The growth rate is the most sensitive parameter of algae to the action of copper, its decrease was noted at the concentration of the pollutant above 150 µg/L, the death of the culture - at 1500 µg/L and above. The number of algae cells in the stationary phase of growth naturally decreases with an increase in the copper content in the medium from 150 to 3750 µg/L. It was found that copper does not affect the efficiency of the photosynthetic apparatus of algae at concentrations that do not lead to the death of the culture. A decrease in the values of the maximum quantum yield of fluorescence, non-photochemical quenching of fluorescence and the maximum relative electronic transport rate below the optimal values can be used as an indicator of the lethal effect of the studied pollutant on D. salina. At a copper concentration of 750 µg/L and above, it was noted: an increase in cell volume, an increase in the number of spherical cells, deformation and perforation of the plasmalemma, the predominance of deformed cells of irregular shape, a twofold decrease in the intracellular content of chlorophyll a and the specific yield of fluorescence per chlorophyll a.