NUMBER OF BACTERIA IN HAPLIC CHERNOZEM CONTAMINATED BY PETROLEUM HYDROCARBONS AFTER AMELIORATION

Bacteria are a sensitive indicator of the state of the soil contaminated with oil and oil products. After the intro-duction of ameliorants, the oil content in the soil changes, which affects the number of bacteria. The aim is to estimate the number of bacteria in petroleum hydrocarbons contaminated Haplic Chernozem after amelioration. Biochar, sodium humate, nitroammophos, and microbiological fertilizer «Baikal EM-1» were added to petroleum hydrocarbons-contaminated Haplic Chernozem (5% petroleum hydrocarbons by weight of soil). After 90 days of the experiment, the number of bacteria in the soil was estimated by the total number of bacteria, determined by the method of luminescent microscopy, the number of actinomycetes, amylolytic and ammonifying bacteria, determined by the method of inoculation on solid nutrient media. The integral indicator of the number of bacteria (IINB) of the soil was calculated before and after the application of ameliorants. When introducing biochar, it is possible to use the total number of bacteria to assess the ecological state of the soil, with nitroammophoska — the number of ammonifying bacteria, sodium humate — the number of actinomycetes, «Baikal EM-1» — the number of amylolytic bacteria. According to the IINB of soils, the most effective dose for remediation with nitroammo-phoska, biochar, and Baikal EM-1 is D0.5, and for remediation with sodium humate, D2. It is advisable to use the results of the study in biodiagnostics and monitoring the state of petroleum hydrocarbons contaminated Haplic Chernozem after amelioration.