Microbial features of mature and abandoned soils in refractory clay deposits.

Processes of soil restoration in anthropogenically disturbed soils is an urgent topic in modern ecology and nature management. Being mediator between mineral soil composition and plant vegetation, soil microbial community is important factor of soil restoration processes. Analysis of main soil nutrition components followed by 16S amplicon sequencing are sufficient methods for primary analysis of novel locations. Here is the primary analysis in a novel location in Northwest Europe (Russia). Main nutrition parameters (pH, P, Na and NH) and 16S rDNA Illumina amplicons were explored in abandoned soils from sandy pit quarry (2 sites) and refractory clay mining dumps (4 sites).Microbial communities of mature soils and dumps are variable and different in terms both nutritional and microbial components. pH, N and TOC are strong predictors for microbial composition. Dumps of refractory clays pQ_2 are non-developed soils, highly acidic and form specific microbial community. Differences between dumps and mature soils in both pre-quaternary and quaternary soils are connected with specific bacterial taxa. Those taxa are connected more with plant composition, not the soil properties themselves. The exact changes in microbial community are unique for different soils and areas.