Formation of symbiotic communities of ciliates, algae, and cyanobacteria in a waterbody of the Ptich’ya Gavan nature park (Omsk)

Abstract

This article deals with the formation of symbiotic communities in a waterbody of the Ptich’ya Gavan nature park (Omsk) at the end of May 2010. The samples were collected by plankton nets, fixed in formalin, and examined with the use of optical microscope. The symbiotic communities consist of ciliates Ophrydium versatile and 35 other species and forms of algae and cyanobacteria inhabiting the pelagic zone of the waterbody. It is found that the species composition of producers in these communities is formed as a result of the higher adaptation of some species to specific conditions regardless of their abundance. The species with high tolerance to abiotic environmental factors (cosmopolitan species), inhabitants of polluted zones, and species with high tolerance to the concentrations of organic matter in water are most abundant.