河流生态径流评价的流量区间组成法

Flow Interval Component Method for Evaluating River Ecological Flow

基于最小生态径流、适宜生态径流(阈值)和最大生态径流,提出了河流生态径流评价的流量区间组成法,依据各生态径流过程将实测径流划分为不同区间,分析评价了蒙江流域八茂站不同时期河流各月生态需水满足程度。实例应用结果表明,河流适宜生态径流计算时,蒙江流域丰、平、枯水期保证率取45%、50%、70%更为合适;水利工程的大量修建使蒙江流域河流径流处于适宜生态径流阈值范围内比例明显减小,且河流的生态需水保证率大幅降低。未来可根据来水情况和流量区组成法确定的流量区间调控河流径流过程,从而维持河流生态系统的健康与稳定。

Based on the minimal ecological flow,optimal ecological flow（threshold）and the maximal ecological flow,the flow interval component method was proposed to evaluate river ecological folw.According to different ecological runoff processes,the measured runoff was divided into different intervals in order to evaluate the guaranteed rates of monthly ecological water demand in different periods.Applying this method to Bamao Station in Mengjiang Basin,the evaluation results show that taking different guaranteed flow rates,such as 45%for the wet season,50%for the normal water season,70%for the dry season,is the most suitable method for calculating optimal ecological flow.Moreover,along with mass construction of water conservancy projects,the proportion of runoff in the threshold of optimal ecological flow is reduced significantly.In the future,the processes of runoff should be controlled by inflow conditions and flow intervals which were defined by flow interval component method,so as to maintain the health and stability of the river ecosystem.