Quantity of Reasonable Distribution of River Ecological Basic Flow Considering the Economic Value of its Own Ecological Functions: a Case Study in the Baoji Section of the Weihe River, China

Reasonable allocation of ecological water and water economics has become a significant challenge for the water resource decision-makers. In this study we propose an approach to assess the quantity of reasonable distribution of the river ecological basic flow using the economic value of its own ecological function. Firstly, water resource is divided into two parts: (i) water resources used for the river ecological basic flow, its economic value was calculated using the results of a reference method; and (ii) water resources used for economic water use, and we calculated its economic benefit; (iii) By using the principle of benefit maximization, we determine the most reasonable distribution of the river ecological basic flow. The Baoji section of the Weihe River, the largest tributary of the Yellow River, Northeast China, is used as a case-study to calculate the reasonable distribution of the river ecological basic flow. The health status of the river and disadvantages of the calculation model are also analyzed. Results indicate that the reasonable allocation of the river ecological basic flow in the Baoji section of the Weihe River is 33.83% of the amount of water resources in the Linjiacun hydrologic station. Based on the calculation of the different functions of the river ecological basic flow, the reasonable distribution can meet the basic environmental functions of rivers, and can result in healthy development of basin. Results also provide a quantitative basis for water resource management in relation to water distribution in the Weihe River.