The Influence of Abiotic Factors on the Structural and Functional Characteristics of the Diatom Algae Cerataulina pelagica (Сleve) Hendey

Abstract—Using the electron microscopy method, the species identity of the diatom Cerataulina pelagica, isolated in pure culture from the coastal waters of the Black Sea in September 2021, has been confirmed. The range of optimal temperature values for the development of this species is identified. The impact of light and biogenic substances on its main structural and functional characteristics has been studied. The acclimation of C. pelagica to various light intensities is carried out by changing the efficiency of photosystem II, the C/Chl a ratio, and the specific growth rate. The morphometric parameters of cells (volume, surface area, and specific surface area) change slightly in the studied light range: 8.5–510 μE/(m² s). The transfer of C. pelagica cells, which have the maximum intracellular pool of nutrients, to seawater depleted in nutrients causes a rapid increase in the C/Chl a ratio, as well as a decrease in the efficiency of photosystem II, the relative rate of electron transport, and the specific growth rate. A high degree of toxicity with copper ion in low concentrations in relation to the studied species is shown.