EN
Water is a basic component of the biosphere and has a unique position in nature, because it is the medium in which all biogeochemical processes occur and which concomitantly participates actively in them. Aquatic environment is inhabited by autochthonous microflora but also by microorganisms populating human or animal gastrointestinal tract. Therefore, from both economic and sanitary point of view, it is not irrelevant which microorganisms occur in water, constituting a source of drinking water for humans and animals. For this reason, periodical microbiological controls of purity of water, which is a source of drinking water, have been carried out.