Home – Home – Jornals – Contemporary Problems of Ecology 2011 number 1

Spread of the major components of the plankton microbial food chain - bacteria, heterotrophic flagellates and infusoria - in the lower reach of the Ob near Salekhard was studied. In early summer, the level of quantitative development and species diversity of protozoa were not high; heterotrophic bacteria were dominating. Their biomass exceeded that of the phyto- and zooplankton. Anthropogenic activization of bacterioplankton was detected at the river region downstream from Salekhard. The data obtained provide evidence of the importance of heterotrophic microorganisms in trophic dynamics and self-purification of the lower Ob.