"Agricultural sulfur microbiome and availability as a function of aridity " core data

Increasing aridity poses a significant threat to soil fertility in dryland farms. Although sulfur (S) is an essential crop macronutrient and a key component of soil organic matter, the influence of aridity on S microbiomes and availability remains unclear. This study integrated metagenomic sequencing and mechanistic modeling to investigate how aridity drives the reorganization of soil S pools and microbial communities in southwest China. Increasing aridity led to significant enrichment of total and adsorbed S but depletion of soluble S fractions, accompanied by reductions in microbial α-diversity, increases in β-diversity, and compositional shifts in key S-transforming taxa. Partial least squares path modeling revealed that aridity regulated soil S transformations through dual pathways—by modifying soil physicochemical conditions and by reshaping the S microbiome that mediates S cycling. Specifically, aridity significantly enhanced total S, available S, and SO42− by improving soil properties. In addition, aridity significantly increased total S and SO42− via mitigating the negative impact of α-diversity on total S and SO42−. These findings demonstrate that aridity-driven interactions between soil conditions and microbial community dynamics govern S availability in dryland agroecosystems, providing new insights into nutrient cycling and ecosystem stability under progressive aridification.