Soil Biogeochemical Cycle Couplings Inferred from a Function-Taxon Network

Soil biogeochemical cycles and their interconnections play a critical role in regulating functions and services of environmental systems. However, the coupling of soil biogeochemical processes with their mediating microbes remains poorly understood. Here, we identified key microbial taxa regulating soil biogeochemical processes by exploring biomarker genes and taxa of contigs assembled from metagenomes of forest soils collected along a latitudinal transect (18 degrees N to 48 degrees N) in eastern China. Among environmental and soil factors, soil pH was a sensitive indicator for functional gene composition and diversity. A function-taxon bipartite network inferred from metagenomic contigs identified the microbial taxa regulating coupled biogeochemical cycles between carbon and phosphorus, nitrogen and sulfur, and nitrogen and iron. Our results provide novel evidence for the coupling of soil biogeochemical cycles, identify key regulating microbes, and demonstrate the efficacy of a new approach to investigate the processes and microbial taxa regulating soil ecosystem functions.

Automated summary

This study identified key microbial taxa regulating soil biogeochemical processes using metagenomic data from forest soils in eastern China, highlighting the sensitivity of soil pH as an indicator for functional gene composition and diversity. A bipartite network inferred from metagenomic contigs revealed microbial taxa regulating coupled biogeochemical cycles between carbon and phosphorus, nitrogen and sulfur, and nitrogen and iron, providing novel evidence for the coupling of soil biogeochemical cycles and demonstrating the efficacy of a new approach to investigate soil ecosystem functions.