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A Comprehensive Accounting of Construction Materials in Belt and Road Initiative Projects
Lingli Hou1, Tomer Fishman1, Ranran Wang1
1Institute of Environmental Sciences (CML), Leiden University, Leiden 2333CC, The Netherlands.
Environmental Science & Technology
|August 20, 2024
Summary
The Belt and Road Initiative (BRI) has accumulated 328 million tons of construction materials, primarily aggregates, in 540 global projects. This study quantifies material use, highlighting overlooked environmental impacts of this infrastructure initiative.
Area of Science:
- Environmental Science
- Materials Science
- Civil Engineering
Background:
- The Belt and Road Initiative (BRI) is a massive global infrastructure project with significant environmental implications.
- The environmental impact of construction materials used in BRI projects remains under-examined, particularly in developing nations.
Purpose of the Study:
- To map and quantify the material stocks embodied in BRI projects worldwide.
- To analyze the types, quantities, and geographical distribution of construction materials used in the BRI.
- To provide a foundation for assessing the environmental sustainability of BRI material flows.
Main Methods:
- Integration of official governmental project reports, geographical information, and material flow analysis.
- Pinpointing and analyzing BRI material stocks by material type, country, region, and sector.
- Quantitative assessment of accumulated construction materials between 2008 and 2023.
Main Results:
- Accumulation of 328 million tons of construction materials across 540 BRI projects globally from 2008 to 2023.
- Aggregates (sand and gravel) represent the largest material share (82%), followed by cement and steel.
- Transportation infrastructure projects utilize the majority of these construction materials, predominantly in Asia and Africa.
Conclusions:
- The BRI entails substantial global raw material consumption, necessitating further environmental impact assessments.
- Data quality limitations were identified, impacting the precision of sustainability evaluations.
- This study establishes a baseline for understanding the material stock-flow-nexus of the BRI, crucial for future environmental research.
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