At the invitation of Professor Zhang Baoqing from the School of Earth and Environmental Sciences, Lanzhou University, Assistant Professor He Xiaogang from the Department of Civil and Environmental Engineering, National University of Singapore, visited our university for academic exchange and delivered a lecture on July 14, 2025.
Reporter: Assistant Professor He Xiaogang, Department of Civil and Environmental Engineering, National University of Singapore
Title: Strategizing Renewable Energy Transitions to Preserve Sediment Transport Integrity
Moderator: Professor Zhang Baoqing, School of Earth and Environmental Sciences, Lanzhou University
Time: 10:00-12:00, July 14, 2025 (Monday)
Venue: Room 501, Qilian Hall, Chengguan Campus, Lanzhou University
Reporter Profile:
Assistant Professor He Xiaogang is a doctoral supervisor at the Department of Civil and Environmental Engineering, National University of Singapore. He completed his undergraduate studies at Tsinghua University, his Master's degree at the University of Tokyo, and received his Ph.D. in Civil and Environmental Engineering, Princeton University in 2019, where he studied under Professor Eric Wood (a member of the U.S. National Academy of Engineering) and Professor Justin Sheffield. He then conducted postdoctoral research at the Woods Institute for the Environment at Stanford University. He joined the National University of Singapore in November 2020. He currently serves as an Associate Editor for Geophysical Research Letters and was awarded the "Outstanding Contribution as an Editor" by the American Geophysical Union (AGU) in 2020. His primary research focuses on the impact of climate change and human activities on hydrological extreme events (such as floods, droughts, and rapid transitions between drought and flood), the coupling of water-food-energy systems, the application of machine learning in hydrology, and robust decision analysis in deep uncertainty environments. He has published multiple papers as first or corresponding author in leading journals such as Nature Water, Nature Sustainability, PNAS, Science Advances, and Water Resources Research.
Report Abstract:
Hydropower is a key low-carbon energy source that contributes to energy conservation and emission reduction in the face of climate change. However, dams can trap sediment (an important resource for climate adaptation), leading to a "mitigation-adaptation" conflict. Taking the Mekong River Basin as an example, hydropower development has led to a 74% reduction in sediment in the delta (40.8 million tons/year). This study proposes a new framework for water-sediment-energy collaborative planning, discovering that replacing 19 high-sediment-trapping hydropower stations with wind and solar power can retain 98% of the sediment while only increasing energy costs by 4%-6%. The sediment benefits (10.4 million USD/ton/year) can offset the additional costs, and the overall cost increase is minimal, only 1%-3%.
School of Earth and Environmental Sciences, Lanzhou University
September 23, 2025
