摘要
选取不同时间尺度(年代际、丰水与枯水期、月份)下的径流,采用Mann-Kendall法和小波变换法分别进行径流变化趋势检验和丰枯突变分析,对比分析了不同小波函数和不同小波消噪阈值确定方法对径流变化分析的影响。结果表明,采用不同的小波函数和小波消噪方法所得的分析结果有一定差异,特别是资料系列长度较短时相差较大,建议采用Stein阈值法确定消噪阈值、采用Marr小波进行径流突变分析,且应在径流变化分析中尽量运用多种方法以提高结果的可靠性。
The results of trend analysis between measured and denoising runoff are compared in this paper,the runoff series are denoised using the method of wavelet denoising firstly,then, runoff trend test and mutation analysis are conducted employing the Mann-Kendall test and wavelet transform respectively under different time scales. The results of runoff trend analysis using different wavelet functions and denoising threshold are also compared. The results indicates that employing different wavelet functions and wavelet denoising methods can get different runoff trend, especially in the case of using short-length runoff series. The paper suggests using Stein threshold method for denoising and Marr wavelet for wavelet transform and mutation analysis. It is better to employ several methods for runoff trend analysis in order to improve the reliability.
出处
《水电能源科学》
北大核心
2009年第5期4-7,共4页
Water Resources and Power
基金
国家自然科学基金资助项目(40701024)
关键词
小波消噪
径流趋势
多时间尺度
突变分析
wavelet denoising
runoff trend
multiple time scales
mutation analysis
