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应用小波变换的多分辨分析功能,对黄河宁蒙河段的流凌、封河、开河、气温和径流序列进行了多时间尺度分析。分析结果显示:宁夏和内蒙古河段流凌日期分别存在一个28年和22年的主周期变化;宁夏河段开河日期不存在明显的周期变化,内蒙古河段封河日期存在一个21~22年的主周期变化;宁夏和内蒙古河段开河日期分别存在一个27年的主周期变化和一个15年的弱周期变化;宁蒙河段冰期气温整体上呈上升趋势,不存在明显的周期变化;宁蒙河段冰期径流变化较为稳定,冰期平均径流序列存在一个22年左右的主周期变化。研究结果有助于全面认知宁蒙河段凌情变化特性,可为区域防凌减灾提供参考信息。
By using the multi-resolution analysis function of wavelet transform, multi-time scale analysis of flow, seal, open river, temperature and runoff sequences in Ningmeng reach of the Yellow River was carried out. The analysis results show that there exists a 28-year and 22-year main cycle changes in the flow Lingling dates of Ningxia and Inner Mongolia respectively. There is no obvious periodic change in the opening of the Ningxia reach and a 21-21 year main cycle change ; There is a 27-year main period change and a 15-year weak period change in Ningxia and Inner Mongolia respectively. The glacial temperature in Ningmei reach an overall upward trend and there is no obvious periodic change. The change of runoff is relatively stable. There is a main period change of about 22 years in the average glacial stream runoff sequence. The results will help to fully understand the changing characteristics of the Ling-ning section of the Ning-Meng River and provide reference information for regional prevention and mitigation.