SINOPSIS

In 36 soil samples studied before and after their long-term storage in an air-dried state, 34 species of Cyanophyta belonging (apart from one species) to Oscillatoriales (Elenk.) Starmach emend. Kondrat. and Nostocales (Geitl.) Elenk. were discovered. After long-term storage the number of species and their frequency decreased appreciably (especially in the Oscillatoriales), latent period of their development in mixed cultures have elongated, and dominance among algae has not been observed. However, a conciderable part of the Cyanophyta species had survived. The reduction of blue-greens' role in the samples from different localities (after long-term storage in an air-dried state) is different. Species richness of the representatives of other algal divisions after long storage of the soil also reduced sufficiently. However, some of their forms turned out to be more stable than Cyanophyta. Soil samples, stored in an air-dried state for many years are not suitable for using in algofloristic research, but they can be useful in obtaining algologically pure cultures of some drought-resistant species of algae.