Soil proteogenomics uncover microbial strategies for soil depth-specific carbon cycling under whole-soil warming conditions.

Soil microbial traits and responses to warming are primarily shaped by soil depth, with distinct metabolic strategies observed at different depths under +4°C warming over 7.5 years.

• Why it matters: Understanding microbial mechanisms controlling soil carbon cycling and their responses to warming is essential for predicting climate feedbacks, especially in subsoils where knowledge is limited.
• What they did: Using genome-resolved proteogenomics in a replicated warming experiment across 0-90 cm soil depths, the study mapped microbial traits, their stratification, and warming responses, revealing depth-specific patterns.
• The result: Warming effects are smaller and diminish over time but are depth-specific, with surface soils showing increased nutrient transport and stress tolerance, while mid- and deep soils exhibit stimulated C1 metabolism, CO oxidation, and nitrogen turnover, influencing soil carbon-climate feedbacks.