以河套灌区地下水位序列为例子,首先对地下水位序列进行了小波消噪,然后采用Mexican Hat小波函数对消噪序列进行了小波变换,并基于此分析了地下水位序列的多时间尺度演变特征.结果表明:不同的时间尺度分辨率下,地下水位序列会表现出不同的周期交替现象,时间尺度在时间域中分布很不均匀,具有明显的局部化特征;小波分析可以清晰地给出各种周期的强弱和分布情况以及突变点,为分析地下水位时间序列的动态变化特征提供了一种新方法.
Based on Mexican Hat wavelet transform, the multi-time-scale of mensal average groundwater level series at an irrigation distinct in Northwest China have been analyzed. The results show that the wavelet transform can clearly demonstrate all kinds of features of groundwater level series, such as the strength and distribution of the period and jump as well as the major periods. The above characteristics exist unevenly in the discussed time domain; the wavelet transform has the advantage of probing the multi-time-scale of hydrology and water resources time series.