Soil chemistry and microbiome modulation through water irrigation containing oxygen, hydrogen, and carbon dioxide nanobubbles

Nanobubble technology has shown considerable promise in sustainable agriculture due to its ability to enhance seed germination, plant growth, and soil quality without leaving harmful residues. While benefits are often attributed to improved soil aeration and soil texture changes (e.g., permeability), nanobubbles may also influence soil microbiome, an essential driver of plant health and nutrient cycling. This study systematically investigated how different nanobubble types—oxygen, hydrogen, and carbon dioxide—modulate soil chemistry and microbial community structure over a 4-week period. Multivariate analyses on microbiome taxonomic composition revealed distinct microbial responses to each gas type. Oxygen and hydrogen nanobubble treatments resulted in more pronounced shifts in microbial composition and functional potential compared to carbon dioxide nanobubbles. These shifts included enrichment of bacterial taxa associated with nutrient turnover, pollutant degradation, and pathogen suppression, such as Flavobacteriaceae, Comamonadaceae, Nannocystaceae, and Blastocatellaceae. Functional predictions showed that oxygen and hydrogen nanobubbles could promote metabolic pathways related to organic compound degradation and remediation of contaminated soil. Microbial network analysis further highlighted the beneficial impacts of nanobubbles on keystone taxa, such as Flavobacteriaceae, which in turn play pivotal roles in shaping soil ecosystem functions. Together, these findings demonstrate that gas-specific nanobubble irrigation can steer soil microbiome dynamics in ways that may enhance soil fertility, resilience, and crop productivity.