Gao_et_al_Data and Code

Fire is a dominant agent of ecosystem transformation worldwide, yet its influence on the ecological stoichiometry that governs fundamental processes from plant production to nutrient cycling and ecosystem stability remains poorly constrained at a global scale. Here, we conducted a global meta-analysis of 2,238 paired observations from 282 studies to quantify fire effects on terrestrial carbon (C), nitrogen (N) and phosphorus (P) pools and their stoichiometric ratios (C:N, C:P, N:P and C:N:P). While ecosystem-level stoichiometry remained homeostatic, we discovered substantial fire-induced shifts within individual ecosystem components. Microbial and soil C:P and N:P ratio of microbial and soil were the most responsive, highlighting a critical reorganization of nutrient capital. These stoichiometric changes were most pronounced following high-severity of frequency fires and particularly those occurring in spring. Furthermore, the magnitude of fire effects was strongly regulated by time since fire and was exacerbated in more productive ecosystems (e.g., those with higher gross productivity) and warmer, wetter climates. Our analysis revealed that post-fire stoichiometric homeostasis at the ecosystem level emerged from compensatory interactions among plant, soil and microbes. We conclude that integrating these key drivers — component-specific responses, climate, and vegetation productivity — into Earth system models is essential for predicting ecosystem biogeochemistry under rapidly changing global fire regimes.