汉江上游洪水特性复杂度分析

以汉江上游的两个代表站——石泉和安康水文站的年径流量及年最大洪峰流量时间序列为例,对径流特性和暴雨洪水特性进行了分析,结果表明:洪水年际变化极不稳定,流量变化幅度很大,年最大洪峰流量变化呈下降趋势;径流年内分配丰枯明显,径流年际分配不均匀,径流量总体呈下降趋势。现采用近似熵(ApEn)及算法复杂度C0作为复杂性测度,对石泉、安康水文站的年径流量和年最大洪峰流量序列进行了复杂性分析,分析得到年径流量的复杂性比年最大洪峰流量的复杂性大,即年径流序列的随机(复杂)程度越大。这一有益的结论表明年最大洪峰流量的可预测性大于年径流量,进一步研究年最大洪峰流量的预测方法对水库防洪具有重要的意义,并为汉江上游的防洪与发电调度起借鉴作用。

Complexity Analysis of Flood Characteristics in the Upper Hanjiang River

In recent years,the frequent and extreme events of the flood bring serious damage to the human society as the influence of human activity and the global warming.Shiquan and Ankang stations are two of the typical hydrological stations in the upper Hanjiang River.According to analyse the characteristics of runoff and storm flood of Shiquan reservior and Ankang reservior,the results show that annual variation of flood is unsteady and the range of flood variation is huge.Overall the variation tendency of annual maximum peak flood of two stations is decreasing.The difference between flood season and dry season of runoff is huge.Annual variation of runoff is uneven and the variation tendency of runoff is decreasing.The time series of annual runoff and maximum peak flow of the two stations is taken for example,using approximate entropy(ApEn) and the complexity of the algorithm(C0) as the measurement of the complexity of runoff and maximum peak flow time series analysis.The results show that: annual runoff is more complexity than annual maximum peak flood at the upper reaches of the Hanjiang River basin.It is said that the randomness of the peak flow is less than the annual runoff series random degree,and the peak flow has the predictability.The analysis results will take supporting role to flood control and power generation dispatching.