???????????????? ???????????????????? ?????????????????????? ???????????????????????????? ????????????, ??????????????????????, ?????????????? ?? ?????????????????? ?????????????????????????? Cyanophyta ???????????????????? ???????????? ???????????????? ????????????. ???????????????????????????? ???? ?????????? ??????????, ???? ?????????? ??????????????????????????, ?? ?????????????? ???????????????????? ??????????, ?????? ?? ?????????????? ?????????? ??????????????. ?????? ?????????????????? ???????????????????????? ???????????????? ???????????? Cyanophyta ??????????????????????, ?????????????????? ???????????? ?????????????????????? ????????????????????, ???????????????? ?????? ???????????????? ?????????????????????????? ?????????????????????? ??????????????????????. ???????????? ???????????????????????? ?? ???????????????????????? ?????????? ???????????????? ???????????????? ?????? ?????????????????? ???????????????????????? ????????????????????: ???????????? ?? ??????????????. ??????????????????????, ???? ?? ???????????????? ???????????????? ???????????? ?????????????????????? ???????????????? Cyanophyta ???????????????? ?????????????????????? ???????? ?? ???????????????? ???? ????????????. ???????????????? ?????????????????????? ???????? ???????????????????? ????????????: Anabaena flos-aquae, A. lemmermannii, A. spiroides, Aphanothece clathrata, Aphanizomenon flos-aquae, Cyanonephron styloides, Microcystis aeruginosa, M. pulverea.

A study of Cyanophyta, with their taxonomic composition, number, biomass, and production in small water-bodies of East Siberia is presented. The shallow well-heated lakes and river reaches as well as mountain lakes were sampled. In order to reveal peculiarities in the species composition of the blue-green algae inhabiting natural water-bodies of different types, we have used results obtained from phytoplankton of the manmade Berezhskoe water-reservoir. An analysis of our data in combination with the literature data allowed us to separate the blue-green algae we studied into two complexes, summer and winter, and to complete a list of most massive species in the Siberian water-bodies, namely Anabaena flos - aquae, A. lemmermannii, A. spiroides, Aphanothece clathrata, Aphanizomenon flos - aquae, Cyanonephron styloides, Microcystis aeruginosa, M. pulverea. Also we showed that intensively developing blue-green algae cause the "water bloom" phenomenon and so make worse the water purity.