Peculiarities of Changes in the Chemical Composition of the Cultural Medium during the Growth of Green Microalgae under Artificial Conditions

The peculiarities of changes in the chemical composition of the cultural medium during the process of vital activity and dying away of the green microalgae <i>Tetradesmus dimorphus</i> (Turpin) M.J. Wynne (= <i>Acutodesmus dimorphus </i>(Turpin) P. Tsarenko) HPDP-108 and <i>Desmodesmus brasiliensis </i>(Bohlin) E. Hegew. HPDP-102 were investigated. It has been shown that during the exponential growth phase at high algal numbers and biomass, the concentration of nitrates and phosphorus phosphates in the cultural medium decreased, which was accompanied by the accumulation of ammonium nitrogen and nitrites. In the phase of culture dying away in the medium with low initial concentrations of inorganic nitrogen and phosphorus phosphate compounds, their complete accumulation and reduction of the duration of this period were noted. At a higher initial content of nutrients, a less rapid decrease of ammonium nitrogen and phosphorus phosphates was observed, which was accompanied by the accumulation of nitrites, and also by a slight fluctuation of the content of nitrates.