Publications

Global soil profiles indicate depth-dependent soil carbon losses under a warmer climate

Wang, Mingming W.; Guo, Xiaowei G.; Zhang, Shuai Z.; Xiao, Liujun X.; Mishra, Umakant; Yang, Yuanhe Y.; Zhu, Biao Z.; Wang, Guocheng W.; Mao, Xiali M.; Qian, Tian Q.; Jiang, Tong J.; Shi, Zhou S.; Luo, Zhongkui L.

Soil organic carbon (SOC) changes under future climate warming are difficult to quantify in situ. Here we apply an innovative approach combining space-for-time substitution with meta-analysis to SOC measurements in 113,013 soil profiles across the globe to estimate the effect of future climate warming on steady-state SOC stocks. We find that SOC stock will reduce by 6.0 ± 1.6% (mean±95% confidence interval), 4.8 ± 2.3% and 1.3 ± 4.0% at 0–0.3, 0.3–1 and 1–2 m soil depths, respectively, under 1 °C air warming, with additional 4.2%, 2.2% and 1.4% losses per every additional 1 °C warming, respectively. The largest proportional SOC losses occur in boreal forests. Existing SOC level is the predominant determinant of the spatial variability of SOC changes with higher percentage losses in SOC-rich soils. Our work demonstrates that warming induces more proportional SOC losses in topsoil than in subsoil, particularly from high-latitudinal SOC-rich systems.