Role of Ecological Factors in Shaping Bacterial Community Structure in Soil from a Former Radium Production Facility
摘要
Bacterial communities in meadow soils, both background and contaminated by former 226Ra production facility activities, were analyzed using 16S rRNA gene amplicon sequencing. Diversity metrics for bacterial communities from contaminated and reference soils showed no significant differences. No seasonal changes in community composition or structure were detected. The dominant phyla in meadow soils were Pseudomonadota, followed by Actinomycetota, Acidobacteriota, and Bacteroidota. Differential abundance analysis at lower taxonomic levels, across both meadow and previously studied forest sites, revealed that genera Flavobacterium, Gaiella, Gemmata, Gemmatirosa, Holophaga, Kofleria, Limnoglobus, Nitrospira, Solirubrobacter, and Tepidisphaera—exhibiting oxidative stress tolerance—were most prevalent in soils contaminated with radionuclides and heavy metals. Technogenic contamination levels in meadow soils were substantially lower than those reported for previously studied forest soils from the same area. Ordination analyses of the combined dataset showed that, unlike meadow soils, forest soils exhibited more pronounced structural differences associated with multicomponent contamination level. Among the ecological factors, all pollutants included in the analysis significantly influenced bacterial communities across meadow and forest sites. However, their separate and combined effects are currently lower than those of soil agrochemical parameters and plant-community type. This may serve as a marker of bacterial community adaptation to the prevailing contamination levels.