基于月径流重构序列变异分析的水文分期方法

A Hydrological Staging Method Based on Variation Analysis of Monthly Runoff Reconstruction Sequence

针对传统汛期和枯期划分方法存在一定主观性的问题,本文提出了基于月径流重构序列变异分析的水文分期方法.该方法将原始月径流序列按照一定的方式进行重新排序,构造重构序列;运用水文变异诊断系统对重构序列进行变异诊断分析确定变异点,通过公式推导得出变异点对应的变异月份;根据变异月份分析汛期和枯期的差异性,确定水文分期.以广东省北江流域为例,选择高道、石角等共计10个水文站的逐月实测流量资料,通过重构各站的月径流序列,并对其进行变异诊断得到两个显著的变异点,据此计算确定相应站点的汛期和枯期.统计各站点汛期和枯期的起止时间规律,确定北江流域汛期为3~8月、枯期为当年9月~次年2月.文中北江流域各水文站分期结果与模糊统计方法比较结果表明,基于变异分析的水文分期方法与基于模糊统计的分期方法结果基本一致,分期结果合理可信,可以满足分期需要.该方法以研究序列的变异点作为划分汛期和枯期的依据,一定程度上克服了水文分期的主观性.

To solve subjective problem of traditional division method with flood season and dry season, a hydrological staging method based on variation analysis of monthly runoff reconstruction sequence was proposed. The original monthly runoff series was rearranged in a certain way to form a new reconstructed sequence. The segmentation points were identified by hydrological variance diagnosis systems and converted to the variation month using a derived formula. It can determine hydrologic stage by analyze the difference between flood season and dry season. The monthly observation data which come from ten hydrological stations have been used to statist the starting and ending times for analysing the segmentation point, these stations were allselected from Beijiang basin in Guangdong province, such as gaodao, Shijiao hydrological station. Finally, this paper determines the flood season of Beijiang river basin from 3 -8 and the dry season from 9 ~ 2. The results of the staging of each hydrological station obtained by the above-mentioned method are compared with the staging results of fuzzy statistics, which shows that the results are basically the same. It is mean that theresults are reasonable and reliable and can meet the staging needs. This method takes the variation point of sequence as the basis for dividing hydrological season can overcomes the subjectivity of hydrological staging to a certain extent.