The construction of water infrastructure in international transboundary river basins, such as dams, hydropower projects, and water diversion systems, has generated significant economic benefits but also caused a range of environmental and ecological issues, hindering the green and sustainable development of these basins. Due to the lack of comprehensive, multi-objective, and cross-sectoral coordination in water infrastructure development across different countries, and the absence of systematic assessments of the economic and ecological impacts of cooperation models, it has been difficult to propose sustainable transboundary water resource utilization plans that ensure benefit-sharing among nations.
To address this challenge, Professor ZHAO Jianshi from the Department of Hydraulic Engineering at Tsinghua University and Professor ZHOU Feng from the College of Geography and Remote Sensing at Hohai University focused their research on the Lancang-Mekong River and its basin (hereafter referred to as the Lancang-Mekong Basin), the world’s sixth-largest river. They developed a basin-wide “water resources-hydropower-food-ecology” simulation model. Using multi-objective optimization and multi-agent cooperative game theory, they assessed the impacts and differences of hydropower infrastructure development on hydropower, agriculture, fisheries, sediment, navigation, and environmental flows under three scenarios: full cooperation, partial cooperation, and non-cooperation.
The study found that: 1) Compared to non-cooperation or partial cooperation, full cooperation in the Lancang-Mekong Basin can increase economic benefits by 3% to 21%. This includes a 10% increase in irrigated rice production (over 20% in the dry season), a 4% increase in downstream hydropower generation, while fishery losses are reduced from 23% to 12%, and sediment transport losses decrease from 60% to 22% (Figure 1). 2) With climate change, water infrastructure development, and the strengthening of ecological goals, the negotiable benefit space for countries further expands, making the full cooperation model increasingly robust. 3) The benefit gains from full cooperation in the basin come at the cost of hydropower losses for China. China’s reservoir construction and management play a critical role in the overall cooperation within the Lancang-Mekong Basin.
Based on this, the study suggests: 1) The construction of water infrastructure in the Lancang-Mekong Basin should establish an upper limit to minimize ecological losses.
2) Countries along the basin should enhance flow regulation in the Lancang-Mekong Basin, strengthening the synergy between water infrastructure and water resource allocation for increased effectiveness. 3) Promote the “Hydropower for Rice” cooperation initiative, where upstream and downstream countries meet their respective needs through energy-food trade within the basin, achieving win-win cooperation and ultimately fostering green and sustainable development in the Lancang-Mekong Basin.
Fig.1 Nonlinear response of economic benefits to different environmental impacts. a. Total benefits of hydropower generation and irrigated rice production versus environmental impacts on fishery and sediment transport under non cooperation and full cooperation. b,c, Incremental benefits of cooperation versus loss in fishery b. and sediment transport c. by country. The results are projected over the period 2041–2050 under the scenario RCP8.5
The research findings, titled “Transboundary cooperation in infrastructure operation generates economic and environmental co-benefits in the Lancang-Mekong River Basin,” were published in Nature Water on June 6, 2024 (//www.nature.com/articles/s44221-024-00246-1).
Dr. YU Yang, a PhD graduate from the Department of Hydraulic Engineering at Tsinghua University, is the first author of the paper. Professor ZHOU Feng and Professor ZHAO Jianshi are the co-corresponding authors. The co-authors include BO Yan from Peking University, GAO Jinyu, HU Shiruo, and LIU Bo from Tsinghua University, Professor Andrea CASTELLETI from Politecnico di Milano, Professor Patrice DUMAS from the International Center for Environment and Development (France), Professor CAI Ximing from the University of Illinois at Urbana-Champaign, Professor LIU Junguo from Southern University of Science and Technology, and Professors WADA Yoshihide and Taher KALIL from the International Institute for Applied Systems Analysis (IIASA). This work was supported by the National Natural Science Foundation of China.
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