The role of dissolved organic matter chemodiversity in driving bacterial and fungal community patterns at a continental scale

Dissolved organic matter (DOM) in natural ecosystems is intimately associated with microbial communities. To unravel the relationship between patterns of DOM and microbial communities at a continental scale, we combined using high-throughput sequencing and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), we characterized DOM chemodiversity and bacteria and fungi community patterns in 55 soil samples collected from a 4000-km sampling through northern to southern in China, which are currently suffering great pressure from climate change. Our research findings demonstrate a clear biogeographic pattern in the diversity of bacteria and fungi, primarily influenced by environmental variables and the distribution patterns of DOM compounds. Soil pH and MAT are key factors that influence the diversity and composition of bacterial and fungal communities. In addition to environmental factors, the diversity of tannin-like compounds plays a crucial role in shaping the biodiversity of bacterial and fungal communities. The composition of protein/amino sugar- and carbohydrate-like compounds, primarily impacts the community composition of bacteria and fungi. This is likely determined by the substrate preferences of microorganisms, while these microbes are evolutionarily conserved.