利用北江干流4个水文站资料建立了年最大洪峰流量序列,运用线性回归分析序列的趋势,利用Mann-Kendall法识别突变点,应用经验模态分解(EMD)分析序列的周期,采用R/S法分析序列的持续性特征,并初步探讨了序列的影响因素.结果表明:4个测站的序列均呈不显著增加趋势,不存在显著突变点,有4~6a、8~10a等多个波动周期;4个序列都具有长期记忆性,未来仍将呈不显著增加趋势.相关性分析表明,南亚夏季季风是序列的显著影响因素,太阳活动则可能影响其周期性.
Based on hydrological data from the 4 stations on the Beijiang main stream,the annual maximum peak flow series were constructed in this paper.The linear regression,Mann-Kendall (M-K) methods,empirical mode decomposition (EMD) and rescaled range analysis (R/S) were used to find out the variation law of the series and the linear correlation was used to analyze the impact factors preliminarily.The results show that there is insignificant change trend in the series,and there exists abruptly jumping points.But all the series have the fluctuating cycles of 4 to 6 a and 8 to 10 a.The series for the 4 stations all get long-term memory characteristics so that the future tendency of the series is indistinctive.The result of the linear correlation shows that South Asian summer monsoon is the main factor to the series and sunspot may affect the cycle of the series.