China's extensive high-speed railway (HSR) network, the world's largest, has resulted in significant material consumption and greenhouse gas (GHG) emissions. This study conducts a bottom-up material metabolism analysis of China's HSR system from 2008 to 2035, examining material stocks, flows, and GHG emissions. Findings reveal that material stocks increased from 0.6 gigatons in 2010 to 3.7 gigatons in 2020, primarily aggregates and cement. Spatial distribution gaps across provinces are narrowing. Increased HSR speed initially increased resource demands, but technological advancements mitigated these increases. The study quantifies the carbon replacement value (CRV) and operational emissions, highlighting the environmental benefits of HSR compared to road and air travel.

Ruichang Mao, Yankun Wu, Jian Chen, Peng Chen, Xiaodong Li