Study on the ecological flow in the middle reaches of Irtysh Rivers

Quantitative measure of the ecological flow of the river is the key to meet its ecological objectives. In this study, data captured at 47 hydrological control transects in the middle reaches of Irtysh River were examined to know the ecological flow, using the simplified 7Q10 method, the slop method, the curvature method and several multi-objective evaluation methods including the weighted sum method, the ideal point method with the scaling coefficient of 1 and the multiply-divide method. These calculation results were evaluated using Tennant method. After having water resources scheduling, ecological protection and other factors considered, the ecological flow is determined as 23.97 m³/s, which is about 21.6% of the nature average discharge of Irtysh River.