The ecological compensation mechanism of the water diversion project to the river basin under the dam in the water source area from the perspective of the whole basin

Water diversion project is a key node to speed up the construction of the national water network and optimize the spatial and temporal allocation of water resources through inter-basin water transfer. It not only alleviates regional structural water scarcity but also serves as important infrastructure for enhancing national water resource strategic security and promoting coordinated regional development. From the perspective of the whole basin, this paper integrates theoretical deduction and case study methods to systematically construct a ecological compensation mechanisms of water diversion project to the river basin under the dam, including “why to compensate”, “who to compensate”, “how much to compensate” and “how to compensate”. The river basin under the dam of the water diversion project of Changtan Reservoir is demonstrated as an example. The results show that, from the perspective of the whole basin, increased water from the water diversion project may affect the water resources and environment of the basin under the dam, and the impact should be assessed to decide whether to implement ecological compensation. The main body of ecological compensation is the beneficiary of water diversion activities, and the compensation object is the affected stakeholders of the river basin under the dam. The compensation standard should be determined based on both costs and values, covering the cost of water resources management and environmental governance, as well as the ecological and economic value of water resources. Ecological compensation can be carried out in various forms such as regional financial compensation, industrial funds, and EOD projects.