Root effects on the temperature sensitivity of soil respiration depend on climatic condition and ecosystem type

Root activity may alter the temperature sensitivity (Q₁₀) of soil respiration. However, we lack a comprehensive understanding of root effects on Q₁₀ across different climatic regions and ecosystem types. Here, we conducted a global synthesis of 87 observations of Q₁₀ values of soil respiration and its components from 40 published studies. We found that roots significantly enhanced Q₁₀ of soil respiration because root and rhizosphere respiration was more temperature-sensitive than the respiration of root-free soil, especially in cold regions (mean annual temperature <10 °C). Moreover, roots significantly enhanced Q₁₀ of soil respiration in grassland and cropland but not in forest ecosystems. Overall, our results suggest that the positive effects of roots on Q₁₀ largely depend on climatic condition and ecosystem type, and are potentially useful for parameterizing and benchmarking biogeochemical and Earth system models.