Yulia Veniaminovna Belfeg

Under the conditions of a model vegetation experiment (30 days), the responses of microbial communities of agro-soddy-podzolic soil of two sites (Chashnikovo, Moscow region) with different organic carbon content (Corg 3,86 and 1,30%) to polymetallic pollution with heavy metals (HM: Cu 660, Zn 1100, Pb 650 mg/kg) and treatment with biochar (5%) and lignohumate (0,25%) Methods of classical inoculation on Czapek agar and analysis of soil lipid profiles by gas chromatography—mass spectrometry, an assessment of the differences in abundance colony forming units (CFU), the biomass of fungi and bacteria, the diversity of cultivated fungi in humus-rich and humus-poor soil. HMs did not have a significant effect on the number of CFU and the number of cultural-morphological types of colonies, but they reduced the biomass of fungi and bacteria in both soils, while this decrease was much more pronounced in a weakly humus soil. In addition, the differences between the soils manifested themselves in a different increase in the proportion of resistant melanized forms of fungi under the influence of HM in a highly humified soil — by 25,9%, and in a weakly humified soil — by 45,7%. The sensitivity and universal significance of structural indicators as indicators of the stability of microbial complexes under chemical contamination of soils of different humus content are discussed; among the studied, the most sensitive and reliable indicators include the assessment of the proportion of melanized fungi.