Temperature sensitivity of soil respiration in China’s forest ecosystems: Patterns and controls

Abstract

Soil respiration, one of the most important carbon fluxes in terrestrial ecosystems, is very sensitive to climate change. Understanding the spatial patterns of temperature sensitivity of soil respiration (Q10) and its controlling factors is very important to quantify the climate–carbon cycle feedback at regional scales. In this study, we conducted a synthesis of 74 field measurements on Q10 value across China’s forests. Based on the overall data, the Q10 values ranged from 1.10 to 5.18, with a mean value of 2.51. Moreover, the largest relative frequency of Q10 values was within the range of 2.0–3.0. The Q10 value in China’s forests was significantly and negatively correlated with mean annual temperature and mean annual precipitation. However, the Q10 values increased with latitude and altitude but there was no obvious relationship between Q10 and longitude. There were no significant differences in Q10 among evergreen coniferous forest, coniferous-broadleaved mixed forest, deciduous broadleaved forest and deciduous coniferous forest. However, the Q10 of evergreen broadleaved forest was significantly lower than that of evergreen coniferous forest and deciduous coniferous forest. The findings may advance our understanding on the different environmental controls of Q10 of soil respiration and also improve our ability to predict regional-scale soil carbon flux in a changing world.