中文摘要：

运用小波分析方法，研究了珠江流域全年、汛期（4-9月）和非汛期（10～翌年3月）三种降水序列时间周期演变特征，结果表明：（1）珠江流域不同区域降水周期不一，大体可分成三个片区，周期尺度分别为6-8a、12～14a和20～21a；（2）珠江流域全年与汛期降水周期以年际变化为主，且两者降水周期分布一致；非汛期降水周期以年代际变化为主，与全年及汛期的降水周期差异较大。

英文摘要：

In this study, we analyzed the period change characteristics of three precipitation series in a year, flood season （from April to September） and non-flood season （from October to March of the following year） based on the methodology of wavelet transformation. The results show： （1） The periods are different in various regions in the Pearl River Basin. The Pearl River Basin can be categorized into three regions by the distribution characteristics of the period. The main period scales are as follows： 6 to 8 years, 12 to 14 years, and 20 to 21 years. （2）The pe- riod of the annual and flood season precipitation is mainly an inter-annual change, and the period distribution between the two is consistent. The inter-decadal variation of non-flood season period is the dominating pattern, and there is a large difference between the period of non- flood season precipitation and that of the annual and flood season.