Bacterial community composition of Hungarian salt-affected soils under different land uses

Salinization and sodification are serious and worldwide growing threats to healthy soil functions. Although plants developed a plethora of traits to cope with high salinity, soil bacteria are also essential players of the adaptation process. However, there is still lack of knowledge on how other biotic and abiotic factors, such as land use or different soil properties, affect the bacterial community structure of these soils. Therefore, besides soil chemical and physical investigations, bacterial communities of differently managed salt-affected soils were analysed through 16S rRNA gene Illumina amplicon sequencing and compared. Results have shown that land use and soil texture were the main drivers in shaping the bacterial community structure of the Hungarian salt-affected soils. It was observed that at undisturbed pasture and meadow sites, soil texture and the ratio of vegetation cover were the determinative factors shaping the bacterial community structures, mainly at the level of phylum Acidobacteriota. Sandy soil texture promoted the high abundance of members of the class Blastocatellia, while at the slightly disturbed meadow soil showing high clay content was dominated by members of the class Acidobacteriia. The OTUs belonging to the class Ktedonobacteria, which were reported mostly in geothermal sediments, reached a relatively high abundance in the meadow soil.