Spatial and Vertical Stratification of Groundwater Microbial Communities Reveals Proteobacterial Dominance and Redox-Driven Ecological Transitions.

ABSTRACT: Groundwater microbial communities exhibit pronounced vertical and spatial structuring driven by physicochemical gradients. Here, we investigated microbial assemblages across surface and subsurface layers of three groundwater wells distributed along a 1.26 km transect in the Wadi Awja aquifer system (Jeddah, Saudi Arabia) using high-throughput 16S rRNA gene amplicon sequencing. Across all samples, Pseudomonadota (Proteobacteria) dominated community composition, accounting for ~50-65% of surface assemblages and increasing to ~90% in deeper strata, indicating strong vertical selection. This depth-associated enrichment coincided with reduced community evenness and the prevalence of metabolically versatile, facultatively anaerobic taxa. Although Actinomycetota, Bacteroidota, and Planctom

SUBMITTER: Aljuaid RS 

PROVIDER: S-EPMC12843820 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature