Diatoms in the karstic water bodies of the nature sanctuary «Paraskiny lakes» (Komi Republic)

First data about diatom composition in karstic lakes of the Izhma river basin are given. In total 327 species and intraspecific taxa from 77 genera and 31 families were revealed. The differences of diatom complexes ecological structure are connected with mineralization, pH level and morphometric peculiarity of water bodies. The main species of phytoplankton, phytobenthos, periphyton of different substrates are shown. Diatom composition characterizes the karstic lakes as freshwater and rather clean ones which need periodical monitoring.