Long-periodic feature of runoff and its effect on riverbed in
Qiantang estuary
ZENG Jian1,2, SUN Zhi-lin1, PAN Cun-hong2, CHEN Gang2
1. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310027, China；
2. Zhejiang Institute of Hydraulics and Estuary, Hangzhou 310020, China
In accordance with the nonstationary hydrological time series,the wavelet method was adopted to analyze the periodic feature and the trend of the runoff in the Qiantang estuary.The complex Morlet function, whose basic characteristic was discussed, was selected to transform the standardized timeseries of the annual runoff discharge.Based on the distribution of module and real of wavelet transform coefficients and wavelet variance, the prominent period of the annual runoff discharge in the Qiantang estuary is 21 years approximately, and it is predicted that the trend of the annual flow is in the low flow period from 2008 to 2010, and then the annual discharge is increase. Combined the observed topographical data, the relationships between the periodic variation of the runoff and riverbed deformation was analyzed. The results show there is a close relationship between them. The riverbed is scoured with straight alignment of river course during high flow period, and deposited with curved alignment of river course during low flow period．
CENG Jian, SUN Zhi-Lin, BO Cun-Hong, CHEN Gang. Long-periodic feature of runoff and its effect on riverbed in
Qiantang estuary. J4, 2010, 44(8): 1584-1588.
［1］ 王文圣,丁晶,李跃清.水文小波分析［M］.北京：化学工业出版社,2005:48．
［2］ LABAT D. Wavelet analysis of the annual discharge records of the worlds largest rivers \ [J\]. Advances in Water Resources, 2008,31(1)：109117．
［3］ CHOU C M. Applying multiresolution analysis to differential hydrological grey models with dual series \ [J\]. Journal of Hydrology, 2007,332(26)：174186．
［4］ LU Xiaoning, DENG Wei, ZHANG Shuqing. Multiple timescale characteristics of runoff variations in middle reaches of Huolin River and their effects \ [J\]. Chinese Geographical Science, 2007,17(2)：143150．
［5］WANG Jun, MENG Jijun. Research on runoff variations based on wavelet analysis and wavelet neural network model: a case study of the Heihe River drainage basin (1944-2005) \ [J\]. Journal of Geographical Sciences, 2007,17(3)：327338．
［6］ 安全,梁川,刘政. 雅砻江中上游径流变化特性的小波分析 \ [J\]. 武汉大学学报：工学版,2008,41(3)：2024．
AN Quan, LIANG Chuan, LIU Zheng. Wavelet analysis of runoff variation characteristics in uppermiddle reaches of Yalong River \ [J\]. Engineering Journal of Wuhan University, 2008,41(3)：2024．
［7］ 成礼智,郭汉伟.小波与离散变换理论及工程实践［M］.北京：清华大学出版社,2005:1316．
［8］ 王文圣,丁晶,衡彤.水文序列周期成分和突变特征识别的小波分析法 \ [J\]. 工程勘察,2003(1):3235．
WANG Wensheng,DING Jing,HENG Tong. Wavelet analysis for the diagnosis of period and jump in hydrological time series \ [J\]. Geotechnical Investigation & Surveying, 2003(1):3235．
［9］ 韩曾萃,戴泽蘅,李光炳,等.钱塘江河口治理开发［M］.北京：中国水利水电出版社,2003:193250．
［10］ 余炯,曹颖. 钱塘江河口段长周期泥沙冲淤和河床变形［J］. 海洋学研究,2006,24(2): 2838．
YU Jiong, CAO Ying. Longterm sediment erosion/deposition and deformation of riverbed in the Qiantangjiang River Estuary \ [J\]. Journal of Marine Science, 2006,24(2): 2838.
