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为了研究三江源径流演变规律,用小波分析方法对三江源唐乃亥、直门达、香达站52年(1956-2007)径流时间序列变化进行了多尺度周期性分析.每个站都有各自的径流丰枯变化周期,三个站作为组成三江源的整体又有共同的周期变化特性.从小波变换时频分布图中得出以下结论:唐乃亥站表现为23年、18年、8年、4年尺度周期变化,直门达站为23年、17年、9年、7年尺度周期变化,香达站为23年、16年、8年尺度周期变化.经小波方差图对主要周期的检验,证明前述结论是正确的.可以看出,三个站表现出了23年的共同周期,同时具有唐乃亥站18年、直门达站17年、香达站16年的近似周期,并且唐乃亥站和香达站有8年的共同周期(直门达站为9年).1956-2007年间,直门达9年尺度下径流变化趋势与香达8年尺度下径流变化趋势非常相似.研究还表明,三个站径流表现出了一致的变化趋势,即2007年以后一段时间内径流还将处于偏丰期,一般持续到2009年,2010-2014年径流将处于偏枯阶段.
In order to study the evolution of runoff in the Three Rivers, a multi-scale periodic analysis of the runoff time series of the Three Rivers, Tangnaihai, Zhimennda and Xiangda stations during the 52 years (1956-2007) was carried out by wavelet analysis. Each station has its own Runoff abundance change cycle, the three stations as a component of the three rivers have a common cycle of change characteristics.From the time-frequency distribution of wavelet transform draw the following conclusions: Tang Nahai station performance for 23 years, 18 years, 8 years, 4 The scale change of annual scale is straightforward, with the change of scale of 23 years, 17 years, 9 years and 7 years, and the change of scale cycle of Xiangda station is 23 years, 16 years and 8 years. , We can see that the above conclusion is correct.It can be seen that the three stations showed a common cycle of 23 years with the similar period of 18 years in Tangnaihai Station, 17 years in Zhimenmen Station and 16 years in Xiangda Station, And Shanda stations have a common cycle of 8 years (straight door station for 9 years.) 1956-2007, straight door 9 years scale runoff trends and Chanda 8-year runoff trends are very similar to the study also showed that , The three stations runoff showed a consistent trend of change, that is, 2007 After a period of time within a runoff will be in overabundant period, usually until 2009, 2010 - The 2014 runoff will be in Pianku stage.