基于生态径流指标的水文情势变化评估新方法  

New method for evaluating changes in hydrologic regimes based on eco-flows metrics

作　　者：张松 郭晓明 周曼 胡挺 ZHANG Song;GUO Xiaoming;ZHOU Man;HU Ting(ChinaThree Gorges Corporation,Yichang,Hubei 443133;Key Research Institute of Yellow River Civilization and Sustainable Development,Henan University,Kaifeng,Henan 475001)

机构地区：[1]中国长江三峡集团有限公司,湖北宜昌443133 [2]河南大学黄河文明与可持续发展研究中心,河南开封475001

出　　处：《水力发电学报》2021年第12期65-76,共12页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(51509099);中国长江三峡集团有限公司自主科研项目(WWKY-2020-0299)。

摘　　要：基于流量历时曲线计算生态径流指标的方法存在诸多不足,也未形成相应的河流水文情势变化评估方法。采用流量过程线重新定义了月、季和年三种时间尺度的生态径流,构建了包含12个月生态盈余和12个月生态赤字的生态径流指标体系,提出了衡量这些指标在建库前后变化度的计算公式,基于月生态赤字发展了月生态风险评估方法,形成了一种河流生态水文情势变化评估方法。将其用于长江宜昌站,评估三峡工程在建库前后的生态水文情势变化。结果表明:重新定义的月、季、年生态径流之间消除了不一致性,香农多样性指数与年生态赤字的年际变化具有更高的相似度,变化度计算公式完全适用于衡量建库前后的变化程度,生态风险图使生态径流指标的实用性大为增强。The method for calculating eco-flows metrics based on flow duration curves has some limitations,and no evaluation system is yet available for the alterations of hydrologic regimes based on eco-flows metrics.This paper first constructs an index system including twelve month eco-surpluses and twelve month eco-deficits,through refining monthly,seasonal and annual eco-flows metrics based on discharge hydrographs.A formula measuring the degrees of change in these indexes is derived,and an ecological risk assessment method based on monthly eco-deficit is worked out.Then,we develop a new method for assessing the alterations of hydrologic regimes,apply it to the Yichang hydrologic station of the Yangtze River as a case study,and evaluate the changes in its hydrologic regimes caused by the Three Gorges project.Results show that the redefinition of the monthly,seasonal and annual eco-flows metrics eliminates the inconsistencies,significantly improving the similarity of the diversity index of Shannon to its annual eco-deficit based on discharge hydrographs.The formula is effective in evaluating the degree of regime changes,and the ecological risk graph helps greatly in enhancing the applicability of eco-flows metrics.

关 键 词：生态径流 生态盈余 生态赤字 流量过程线 流量历时曲线 

分 类 号：TV213[水利工程—水文学及水资源]