Trifonova Tatiana A. RussiaLomonosov Moscow State University, MSU, Leninskiye Gory, Moscow, 119991tatrifon@mail.ru Author's articles Assessment of Water Pollution Level, Processes of a Nitrification and Self-Treating of Ammonium Ions in a Small Water Reservoir of Ilevna Study of the Effect of Antibiotics of Various Groups on the Nitrification Activity of Sod-podzolic Soil by the Method of Laboratory Modelling