Exogenous carbon complexity and C:N stoichiometric ratio co-regulate soil priming effect in a subtropical forest

The quality of exogenous substrates have strong influences on the direction and magnitude of soil priming effect (PE). However, the synergistic regulation of PE by the molecular-structure complexity and carbon-to‑nitrogen (C:N) stoichiometric ratio of added substrates remains poorly understood, particularly regarding how the underlying mechanisms shift with changes in edaphic factors such as nutrient availability, microbial biomass, and enzyme activities.