LI Meng-chu, HU Chun-hong (State Key Laboratory of Simulating and Controlling of River Basin Hydrologic Cycle China Institute of Water Resources and Hydropower Research, Beijing 100038, China)

Abstract: Based on water & sediment load series of Xiaolangdi, Huanyuankou, Gaocun, Lijin Station and bankfull discharge series of Huanyuankou, Gaocun, Lijin Station, the multi-time scale characteristics of the lower Yellow River are analyzed by using wavelet analysis in this paper. The results show that there are obvious periodic oscillations of 3a, 9a, 14a and 23a for the runoff series, the prime period is 23a, there are obvious periodic oscillations of 5a, 11a, 23a and 36a for the sediment load series, the prime period is 11a; there is obvious periodic oscillation of 24a for the bankfull discharge series. The multi-time scale characteristics of runoff and sediment load are similar, which influence the period of bankfull dis charge series. Due to the natural factors and the actions of human being, the characteristics in different time scale are inconsistent. The point of discontinuity is related to time scale. The points of discontinuity of water & sediment load and bankfull discharge series of the lower Yellow River are in 1957, 1968, 1980, 1991, 2003.

Key words: the lower Yellow River, wavelet analysis, multiple time scale analysis, bankfull discharge

Published in: Journal of China Institute of Water Resources and Hydropower Research (Vol. 10 No. 3, 2012)