Legume cover under Camellia oleifera forests enhances understory biomass carbon storage and soil CO2 flux but declines soil inorganic carbon storage on a karst steep slope

Alfalfa cover is recommended for improved understory vegetation aboveground and vegetation root biomass carbon storage, soil physicochemical properties, and soil microbial community stability and network stability, whereas it may not be recommended due to increased soil CO₂ flux and global warming potential, as well as reduced soil inorganic carbon storage. This study first demonstrated the trade-off between understory vegetation aboveground and vegetation root biomass carbon storage and soil inorganic carbon storage, and this trade-off should be carefully considered when conducting multi-storage management.