不同时间尺度下的生态径流风险评价方法  

A Risk Assessment Method for Ecological Flows under Different Time Scales

作　　者：王飞龙 郭晓明 张松 胡挺 WANG Fei-long;GUO Xiao-ming;ZHANG Song;HU Ting(China Three Gorges Corporation,Yichang 443100,China;Research Center on Yellow RiverCivilization and Sustainable Development,Henan University,Zhengzhou 450046,China)

机构地区：[1]中国长江三峡集团有限公司,湖北宜昌443100 [2]河南大学黄河文明与可持续发展研究中心,郑州450046

出　　处：《长江科学院院报》2023年第11期29-35,共7页Journal of Changjiang River Scientific Research Institute

基　　金：国家重点研发计划项目(2021YFC3200302);国家自然科学基金项目(51509099,U2040212)。

摘　　要：生态盈余与生态赤字是评估河流生态水文状况的指标之一,但现有计算方法缺乏统一度量,无法据此判断河流生态水文状况在不同月、季、年之间的优劣。基于流量过程线提出了一种不同时间尺度下的生态盈余与生态赤字计算方法,年生态盈余为第75分位数流量过程线以上的年多余径流与年可能最大多余径流之比,年生态赤字为第25分位数流量过程线以下的年不足径流与年可能最大不足径流之比,月、季生态盈余与生态赤字类似定义,并基于生态赤字将径流减少带来的生态风险划分为4个等级:无风险、低风险、中风险、高风险。利用新方法对金沙江下游屏山站资料进行了分析。结果表明:新方法克服了现有方法的局限性,生成的生态风险图显示了屏山站1940—2012年中每个月、季和年的风险水平,可为今后设计生态径流调控措施提供评估手段。Ecological surplus(ES)and ecological deficit(ED)are indicators used to assess the ecological hydrological conditions of rivers.Previous studies have established calculation methods but lack measurable indicators to determine the extent of runoff surplus or deficiency.This paper introduces a novel method for calculating ES and ED based on discharge hydrograph(DH)as a way to evaluate river ecological runoff.The annual ES is determined by the ratio of annual runoff surplus above the 75 th quantile discharge hydrograph to the annual possible maximum runoff surplus.Similarly,the annual ED is calculated as the ratio of annual insufficient runoff below the 25th quantile discharge hydrograph to the annual possible maximum insufficient runoff.Monthly and seasonal ES and ED are defined in a similar manner.Based on the ED,the ecological risk arising from reduced runoff is categorized into four levels:no risk,low risk,medium risk,and high risk.Data from the Pingshan station in lower Jinsha River were utilized to illustrate the new method.The resulting risk map presents the risk levels for each month,season,and year at the Pingshan station from 1940 to 2012.This new method overcomes the limitations of traditional approaches and provides an assessment method for designing ecological runoff control measures in the future.

关 键 词：生态径流 生态盈余 生态赤字 风险评估 

分 类 号：TV213[水利工程—水文学及水资源]