The temperature sensitivity of soil CO2 release is modified by virus-bacteria interactions

The temperature sensitivity (Q 10 ) of soil carbon (C) release is key to predicting carbon-climate feedback, yet omitting microbial interactions, especially with soil viruses, introduces substantial uncertainty.To address this, we performed 30-day and 365-day incubations with metagenomics and metatranscriptomics profiling.We found that soil viruses significantly decreased Q 10 during 30-day incubation.Over 365-day incubation, however, their effects on microbial metabolism and Q 10 were temperaturedependent.The relative abundance of pathways related to viral replication, including those for lytic cycle initiation (e.g., propanoate metabolism decreased by 15.24%), and the energy supply (e.g., lipoic acid metabolism decreased by 20.95%), became less abundant as temperature rose from 15°C to 35°C.Metatranscriptomics data confirmed this trend, with upregulation of metabolic functions related to viral infection and replication at 15°C.Thus, temperature-driven variations in viral activity underlie the contrasting roles of soil viruses in regulating Q 10 .This study provides the first evidence of temperature-dependent viral regulation of microbial metabolism and Q 10 , highlighting the need to incorporate soil viruses into carbon-climate models.