丹江口水库入出库径流多时间尺度变化特征分析

为了认识丹江口水库运行对河道径流改变的影响,更好地指导汉江流域水资源利用,采用Morlet小波分析方法,对丹江口水库1956~2012年入库及出库径流序列进行研究,探讨了该水库入出库径流的丰枯变化情况及其准周期特征。研究结果表明,20世纪90年代以前,丹江口水库来水量经历了多次丰枯交替变化过程,其中,60年代中后期、70年代中期和80年代前期为丰水期,其余为枯水期;20世纪90年代以后,丹江口水库来水呈现出整体偏枯的趋势;水库运行对径流的影响主要体现在对年内分配过程的改变上,通过拦蓄汛期洪水,加大了枯期的下泄水量;水库的调蓄并未改变径流的主要周期,入库和出库径流均保持10个月尺度的主周期,其他时间尺度上的周期变化不太明显。

Multi-temporal scale variation characteristics of inflow and outflow of Danjiangkou Reservoir

In order to understand the influence of Danjiangkou Reservoir operation on river runoff and better guide the water re-sources utilization of Hanjiang River Basin, this paper analyzes the inflow and outflow series of Danjiangkou Reservoir from 1956 to 2012 by wavelet analysis and explores the inflow and outflow variation and quasi-period characteristics. The analysis results show that the inflow of Danjiangkou Reservoir experienced dry-wet alternate process many times before the 1990s, among which middle and late 1960s, middle 1970s and early1980s were wet periods and the rests were dry periods;after 1990s, the inflow of Danjiangkou Reservoir presented a relatively dry tendency in general. The Danjiangkou Reservoir operation mainly influences the intra-annual runoff allocation, which increase the discharge in dry season through impoundment in wet season. The reservoir op-eration does not change the main periodicity and the inflow and outflow are still in 10-month-scale period and the periodic vari-ation of other time scale is not obvious.