黑河流域莺落峡站河道内生态需水研究

The Study of Ecological Water Demand at Yingluoxia Station of Heihe River

生态需水是当前水问题研究中的一个热点问题,对于生态环境急剧恶化的内陆干旱区来说,这一研究尤为紧迫。气候变化及人类活动导致水文变异,进而改变了当地生态系统的水文及生态平衡状况。文章采用黑河流域莺落峡站1947-2006年月径流序列资料,运用差积曲线-秩检验联合法来识别水文过程变异点并分析变异成因,然后对各月平均流量序列用线性矩法推求GEV分布参数,求出概率密度最大流量,将其视为相应月河道内生态流量,可以得到黑河莺落峡站河道内生态需水情况。结果表明,基于水文变异情况分析河道内生态需水的计算方法在黑河上游是可行的;水文变异前后,站点满足生态需水频率会发生显著变化,因气候原因而导致的径流量变化是很难避免的,科学合理计算生态需水对干旱区河流生态管理和经济社会可持续发展有重要作用和意义。

It is a hot issue of ecological water demand in the study of water problem in recent years,especially in arid areas where the ecological environment deteriorated rapidly.Climate changes and human activities can lead to hydrological change,which means the local hydrological condition has changed and broke the ecological balance.The authors adopted monthly runoff series data of 60 years at hydrological monitoring station of Yingluoxia in the Heihe River basin during the period 1947-2006.The difference plot curve-combined method of rank test was used to identify the change point of hydrological processes and causes of these changes.On this basis,L-moment is used to evaluate the parameters of generalized extreme value（GEV） distribution of the monthly flow series before hydrological change,and to calculate the maximum probability density runoff,which is the ecological water demand of that month.The result shows that the ecological calculating method which takes the hydrological change into consideration is practicable in the Heihe River.Before and after the hydrological variability,the frequency to meet the ecological water demand will change significantly at Yingluoxia station.The climatic reasons inevitably exert influence on the volume of the runoff.So it is important to get a better understanding of ecological water demand in river ecosystem management and socio-economic sustainable development in arid areas.