Furtak, KarolinaMarzec-Grządziel, AnnaGrządziel, JarosławNiedźwiecki, Jacek2026-06-262026-06-262026Turk J Agric For (2026) 50: 366-376ISSN: 1300-011X eISSN: 1303-617310.55730/1300-011X.3357https://bc.iung.pl/handle/123456789/4798https://journals.tubitak.gov.tr/agriculture/vol50/iss3/9/Fluvisols develop in river valleys through the accumulation of alluvial sediments. They are characterised by high fertility and are extensively used for agriculture. This study aimed to identify the core microbiome of fluvisols in the Vistula Valley and to examine its relationship with the basic physicochemical properties of the soils. Six types of fluvisol (very light, light, medium, and heavy) from four locations in Lublin province were analysed, with samples collected in 2018 and 2022. The microbiome structure was determined by sequencing the V3–V4 region of the 16S rRNA gene and was compared with soil parameters such as pH, electrical conductivity, organic matter, nitrogen, carbon, and metal contents. A core microbiome, dominated by Acidobacteria_Gp6 (ASV_018) and Rhizobiales (ASV_001), was identified in all samples. Together with Actinobacteria and Proteobacteria, these taxa perform key ecological functions, including nutrient cycling, supporting plant growth, and maintaining soil ecosystem stability. The results confirm the hypothesis that specific bacterial groups within the core fluvisol microbiome contribute to its high quality and agricultural suitability. The data provide a basis for further research into the functional role of the floodplain soil microbiome and its resilience to periodic flooding.enCore microbiome, soil, bacteria, fluvisols, floodplainsArticle