Productivity-driven decoupling of microbial carbon use efficiency and respiration across global soils.

ABSTRACT: Despite extensive research on soil microbial carbon (C) use efficiency (CUE), its linkage to actual soil C storage remains ambiguous. A key uncertainty is that CUE estimates from short-term labeling incubations assume a linear negative relationship with respiration rates, overlooking nonlinear interactions and long-term microbial acclimation. Here, we use a stoichiometry-based approach to estimate CUE (CUE_ST), which links soil resource availability to microbial demand and captures microbial adaptability under resource constraints. We synthesized 1094 paired observations of CUE_ST and heterotrophic respiration rate (R_h) across natural ecosystems and found a nonlinear relationship between them governed by ecosystem productivity. In low-productivity arid

SUBMITTER: Cui Y 

PROVIDER: S-EPMC12802823 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature