Warming alters routing of labile and slower-turnover carbon through distinct microbial groups in boreal forest organic soils

► Fungal incorporation of slower turnover SOC increased by up to 31% with warming. ► Incorporation of faster turnover SOC into Gram+ bacteria doubled with warming. ► Warming altered decay patterns and increased microbial biomass by as much as 60%. ► Warming thus may influence composition of SOM via decay and necromass formation.