Metagenomic analysis of fire-affected rotational-cultivation soils in northern Thailand compares charcoal-mixed surface (0-2 cm), leaching (10-20 cm), and deep (100 cm) layers. Microbial composition and functional genes stratified strongly by depth, and resistance genes persisted without obvious clinical inputs.
Key findings
- Surface soil had higher nutrients and activity but lower Shannon diversity/evenness. Actinomycetota and Bacillota dominated near the surface, while Acidobacteriota and Pseudomonadota increased below. Biogeochemical functions stratified, and rifamycin, macrolide, and glycopeptide resistance genes were most abundant at 100 cm.
Why this matters globally
Vertical profiles prevent fire and soil-management assessments from focusing only on the surface and add environmental-resistome evidence relevant to One Health. Intrinsic genes must be distinguished from mobile genes and pathogens.
Thai researcher contribution
Mahidol University and BIOTEC generated metagenomes from a Thai rotational-cultivation system, integrating land use, soil microbiology, nutrient cycling, and AMR.
Limitations to consider
Site and replicate counts are not stated. Observational sampling cannot fully separate fire from depth, soil, plot, or land-use history. Metagenomes show genetic potential, not expression, viability, or resistance-gene transfer.