Evaluation and improvement of Lancang Mekong River Basin cooperation

Abstract:

Basin-scale cooperation can resolve water disputes among various stakeholders of transboundary rivers, and improve their capacities to cope with extreme drought events under climate change. In this study, Lancang Mekong River Basin (LMB) emergency cooperation – three-phase water supplement in 2016 – is taken as a case, and multi-disciplinary knowledge and physical mechanisms based models are adopted to evaluate the cooperation benefits and the room for improvement systematically. Results show that emergency water supplement can promote nearly 5% downstream agricultural benefits, which can be further improved by more scientific spatial and temporal water re-allocation among different stakeholders. Meanwhile, the external hydrological conditions significantly affect the incremental benefits and efficiency of cooperation. With the streamflow and rainfall decrease, the incremental benefits increase from 1% to 10% of total benefits, while the marginal substitution rates (MRS) between upstream hydropower benefit loss and downstream agricultural benefit gain decrease from 50 to 10. Even so, the MRS of 10 is still considerable, and the cooperation potential in dry years is enormous. The quantitative results can provide guidance and support for transboundary basin cooperation and sustainable management.