基于生态流量阈值的河流水文健康演变定量归因  

Quantifying attribution of the river hydrological health variation based on ecological-flow threshold method

作　　者：江善虎 周乐[1,2] 任立良 王孟浩 卫林勇[2] 袁飞 JIANG Shanhu;ZHOU Le;REN Liliang;WANG Menghao;WEI Linyong;YUAN Fei(Sate Key Laboratory of Hydrological-Water Resource and Hydraulic Engineering,Hohai University,Nanjing 210098,China;College of Hydrological and Water Resource,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]河海大学水文水资源学院,江苏南京210098

出　　处：《水科学进展》2021年第3期356-365,共10页Advances in Water Science

基　　金：国家重点研发计划资助项目(2016YFA0601504);国家自然科学基金资助项目(51979069)。

摘　　要：环境变化改变了河流水文情势,影响了河流的生态系统健康,亟需开展变化环境下河流水文健康演变定量归因方法研究。选取北方半干旱地区老哈河流域为研究区,依据流域内3个水文站、17个雨量站和6个气象站1964—2016年数据,基于可变下渗容量模型还原河流的天然流量序列;采用概率密度法计算河流生态流量,基于生态流量阈值推求河流水文健康等级;基于“观测-模拟”对比分析法,定量分离气候变化和人类活动对河流水文健康情势的影响。结果表明:人类活动是甸子和太平庄子流域自1980年以来河流水文健康情势退化的主要原因,其贡献率分别为86.9%和87.9%;大面积农业灌溉用水引起地表径流下降以及水利工程改变天然水文情势,影响了河流水文健康情势;90年代降水量较为充沛,研究流域受人类活动影响程度较小,河流水文健康等级维持在较高的水平。综合生态流量阈值和“观测-模拟”对比分析方法可定量识别河流水文健康情势演变原因,为适应环境变化的河流健康管理提供科学依据。Environmental change has altered the river hydrological health regimes,and consequently affected the ecological health of river.Therefore,it is essential to develop a method to quantitatively analyze the attribution of river hydrological health evolution.This study selected the typical semi-arid Laohahe River basin in Northern China as a case study area.Observation data were obtained from 3 hydrological stations,17 rain gauge station and 6 meteorological stations in the study area.Firstly,the natural streamflow series from 1964 to 2016 was reconstructed using the observations and the Variable Infiltration Capacity(VIC)model.After that,the level of river hydrological health(H)was assessed based on the ecological flow threshold,which was calculated by probability density curve.Finally,the‘simulated-observed’comparison method was adapted to quantify the effect of climate changes and human activities on the river hydrological health.Results showed that human activities were the major factors that have caused river hydrological health deterioration since 1980 in Dianzi and Taipingzhuang sub-basins,which accounted for 86.9%and 87.9%,respectively.Widespread agricultural irrigation and reservoir operation were the two crucial reasons that caused the alterations of natural hydrological regime,which further led to the river ecological destruction over Laohahe River basin.Whereas,increasing rainfall in 1990s had a significant effect on maintaining river hydrological health because the large amount of rainfall helped reduce the human activities influence.The case study demonstrates that the attribution of river hydrological health evolution can be quantitatively described based on ecological-flow threshold and‘simulated-observed’comparison method,which will provide scientific basis for river ecology protection and water resource management under changing environment.

关 键 词：生态流量 河流健康 气候变化 人类活动 变化归因 

分 类 号：TV121[水利工程—水文学及水资源]