Abstracto

Analysis on changing characteristic of runoff series of Weihe River

Chun-yan Huang, Jian-xia Chang, Zhi-wei Han, Zhi-liang Wang, jun Tang

The Weihe River is the largest tributary of the Yellow River. The annual runoff contributes to 80% of ShanXi province’s GDP and directly supports 64% of the population of ShanXi province. In order to best maximize water resources management, the runoff series from six hydrologic gauging stations (Huaxian, Lintong, Linjiacun, Xianyang,Zhangjiashan and Weijiabao) are obtained, the Mann–Kendall test, and wavelet transform methods were used to detect the characteristic of runoff variation from 1960 to 2005. The results show that: (1) the runoff present a downward trend over the past 46 years, and the trends are intensified downstream; (2) most of the abrupt changes in runoff appear in the early 1970s, early 1980s to middle 1990s through the result of the Mann–Kendall test; and (3) the annual runoff periods of the WeiHe include 2~4a, 5~6a, 11~14a, 24~26a, respectively. The results of this study imply that less precipitation and warmer climate in the basin are the primary factors that cause this decreasing trend of runoff